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Dissertations / Theses on the topic 'Clay products'

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Published: 10 December 2022
Last updated: 28 January 2023

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1

Umar, I. M. "Uptake of fission products onto clay minerals." Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376882.

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2

Michael, Paul J. "Studies of clay minerals and their decomposition products." Thesis, Aston University, 1989. http://publications.aston.ac.uk/9813/.

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Mõssbauer spectroscopy and X-ray diffraction of five coals revealed the presence of pyrite, illite, kaolinite and Quartz, together with other minor phases. Analysis of the coal ashes indicated the formation of hematite and an Fe (3+) paramagnetic phase, the latter resulting from .the dehydroxylation of the clay minerals during ashing at 700 to 750 C. By using a combination of several physicochemical methods, different successive stages of dehydroxylation, structural consolidation, and recrystallisation of illite, montmorillonite and hectorite upon thermal treatment to 1300 C were investigated. Dehydroxylation of the clay minerals occurred between 450 and 750 C, the X-ray crysdallinity of illite and montmorillonite remaining until 800 C. Hectorite gradually recrystallises to enstatite at temperatures above 700°C. At 900 C the crystalline structure of all three clay minerals had totally collapsed. Solid state reactions occurred above 900 C producing such phases as spinel, hematite, enstatite, cristobalite and mullite. Illite and montmorillonite started to melt between 1200 and 1300°C, producing a silicate glass that contained Fe(3+) and Fe(2+) ions. Ortho-pnstatite, clino-enstatite and proto-enstatite were identified in the thermal products of hectorite, their relative proportions varying with temperature. Protoenstatite was stabilised with respect to metastable clinoenstatite upon cooling from 12000 C by the presence of exchanged transition metal cations. Solid state Nuclear Magnetic Resonance spectroscopy of thermally treated transition metal exchanged hectorite indicated the levels at which paramagnetic cations could be loaded on to the clay before spectral resolution is significantly diminished.
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3

Bogahawatta, Vedananda Tilakasiri Loku. "The influence of fabrication effects on the strength of fired clay products." Thesis, Queen Mary, University of London, 1990. http://qmro.qmul.ac.uk/xmlui/handle/123456789/25783.

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A study has been made of the enhancement of the mechanical strength of bricks fabricated from five Sri Lankan Quaternary and post-Quaternary brick clays with the objective of identifying and optimising those factors which control the quality and performance characteristics of fired clay products of this type. Mineralogical investigations have shown that the clays are predominantly kaolinitic. Of the accessory minerals, feldspars and gibbsite are the chief constituents. The experimental programme involved the development of feasible processing techniques for clay bodies, the establishment of optimum heat treatments for their firing, and the testing and evaluation of material properties of the fired products. The microstructures of fired materials have been characterized using optical and electron microscopical techniques, as well as X-ray diffraction, electron probe microanalysis and chemical analysis. A limited study was also made of the durability of laboratory fired specimens. Methods of strength enhancement included use of the reactions of phosphates with natural clays, use of mineralizers to induce mullitization and surface coating by an efflorescence process. A kinetic analysis based on the first order kinetics is proposed for the estimation of optimum firing conditions for kaolinitic clays. The study has shown that surface coating of bricks increases the load at the elastic limit by up to 30% and the ultimate failing load by 19% in the clays examined. The measured increases in modulus of rupture and modulus of elasticity are over 33% and 40% respectively. A fabrication technique which requires the incorporation of phosphates has been developed. This provides the possibility of lowering the peak temperature of firing to 500°C. Flexural strength increase of up to 60% over the normally fired unbonded specimens can be achieved using this technique. Relevant compatibility relations in the ternary system Si02- P205-AI203 at 500'C are proposed. The presence of an optimum amount of mineralizer in a clay body may alter its sintering characteristics resulting in an increase in modulus of rupture up to 55%. However, uncontrolled additions exceeding 4 wt% cause deleterious effects. Microstructural analysis provides evidence that liquid phase sintering, development of mullite, development of pores and bloating are the dominant strength determining features in these clays. An empirical equation correlating the functional relation between modulus of rupture, mullite content and porosity is proposed. Mechanisms of strength development are discussed in the light of these findings.
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4

Nelson, Tiffany S. "Synthesis and Characterization of Crosslinked Polysiloxane-Clay Nanocomposites for Uses in Skin Care Products." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1154620091.

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5

Al-Fouzan, Abdulrahman M. "Polyethylene Terephthalate / clay nanocomposites. Compounding, fabrication and characterisation of the thermal, rheological, barrier and mechanical properties of Polyethylene Terephthalate / clay nanocomposites." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5283.

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Polyethylene Terephthalate (PET) is one of the most important polymers in use today for packaging due to its outstanding properties. The usage of PET has grown at the highest rate compared with other plastic packaging over the last 20 years, and it is anticipated that the increase in global demand will be around 6% in the 2010-2015 period. The rheological behaviour, thermal properties, tensile modulus, permeability properties and degradation phenomena of PET/clay nanocomposites have been investigated in this project. An overall, important finding is that incorporation of nanoclays in PET gives rise to improvements in several key process and product parameters together - processability/ reduced process energy, thermal properties, barrier properties and stiffness. The PET pellets have been compounded with carefully selected nanoclays (Somasif MAE, Somasif MTE and Cloisite 25A) via twin screw extrusion to produce PET/clay nanocomposites at various weight fractions of nanoclay (1, 3, 5, 20 wt.%). The nanoclays vary in the aspect ratio of the platelets, surfactant and/or gallery spacing so different effect are to be expected. The materials were carefully prepared prior to processing in terms of sufficient drying and re-crystallisation of the amorphous pellets as well as the use of dual motor feeders for feeding the materials to the extruder. The rheological properties of PET melts have been found to be enhanced by decreasing the viscosity of the PET i.e. increasing the 'flowability' of the PET melt during the injection or/and extrusion processes. The apparent shear viscosity of PETNCs is show to be significantly lower than un-filled PET at high shear rates. The viscosity exhibits shear thinning behaviour which can be explained by two mechanisms which can occur simultaneously. The first mechanism proposed is that some polymer has entangled and few oriented molecular chain at rest and when applying high shear rates, the level of entanglements is reduced and the molecular chains tend to orient with the flow direction. The other mechanism is that the nanoparticles align with the flow direction at high shear rates. At low shear rate, the magnitudes of the shear viscosity are dependent on the nanoclay concentrations and processing shear rate. Increasing nanoclay concentration leads to increases in shear viscosity. The viscosity was observed to deviate from Newtonian behaviour and exhibited shear thinning at a 3 wt.% concentration. It is possible that the formation of aggregates of clay is responsible for an increase in shear viscosity. Reducing the shear viscosity has positive benefits for downstream manufacturers by reducing power consumption. It was observed that all ii three nanoclays used in this project act as nucleation agents for crystallisation by increasing the crystallisation temperature from the melt and decreasing the crystallisation temperature from the solid and increasing the crystallisation rate, while retaining the melt temperature and glass transition temperatures without significant change. This enhancement in the thermal properties leads to a decrease in the required cycle time for manufacturing processes thus potentially reducing operational costs and increasing production output. It was observed that the nanoclay significantly enhanced the barrier properties of the PET film by up to 50% this potentially allows new PET packaging applications for longer shelf lives or high gas pressures. PET final products require high stiffness whether for carbonated soft drinks or rough handling during distribution. The PET/Somasif nanocomposites exhibit an increase in the tensile modulus of PET nanocomposite films by up to 125% which can be attributed to many reasons including the good dispersion of these clays within the PET matrix as shown by TEM images as well as the good compatibility between the PET chains and the Somasif clays. The tensile test results for the PET/clay nanocomposites micro-moulded samples shows that the injection speed is crucial factor affecting the mechanical properties of polymer injection moulded products.
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6

Taylor, Garth Vivian Asquith. "The use of microwave energy to initiate autogenous combustion for the firing of heavy clay products." Thesis, Staffordshire University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244378.

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7

Bories, Cécile. "Etude des caractéristiques d'un porogène d'origine biosourcée et mécanismes mis en oeuvre pour l'obtention d'une brique de construction micro-poreuse à haute performance thermique et mécanique." Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0015/document.

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L’objectif de ces travaux consiste à développer de nouvelles briques de terre cuite à base d’agents porogènes biosourcés dans le but d’obtenir des matériaux à haute performance thermique. Les matières premières, argile et biomasse, ont d’abord été caractérisées de manière individuelle. L’utilisation de co-produits agricoles (paille de blé, tourteau de tournesol et farine de noyaux d’olive) en tant qu’agents porogènes pour l’obtention de briques de terre cuite porosées a ensuite été étudiée. L’intérêt d’ajouter des éléments biosourcés entraînant une augmentation de la porosité, une augmentation de la résistance thermique malgré une diminution des propriétés mécaniques a alors été démontré. Toutefois, des problèmes de plasticité causant des soucis de mise en forme au niveau des échantillons ont été identifiés. Après avoir optimisé le taux de sable, l’impact de la granulométrie des matières végétales ainsi que leur taux d’incorporation ont été évalués. Une porosité maximale de 34,4 %, constituée de macropores, a été obtenue dans les conditions expérimentales optimales conduisant à une conductivité thermique de 0,45 W/m.K, soit une diminution de 15 % par rapport à un échantillon de référence sans matière végétale. Afin de continuer à améliorer les propriétés du matériau argileux obtenu, il a ensuite été envisagé de créer une microporosité en modifiant chimiquement les matières végétales qui seraient ensuite dégradées lors de la cuisson. Pour cela, les matières végétales ont été modifiées soit par imprégnation directe de carbonates soit par greffage de nouvelles fonctions carbonates ou esters. Les matières ainsi modifiées ont ensuite été incorporées dans les formulation de terre cuite et les propriétés des matériaux obtenus ont été mesurées (physiques, mécanique et thermique). Enfin, l’impact environnemental potentiel des échantillons contenant des additifs modifiés a été étudié à travers une Analyse de Cycle de Vie. Les différents scénarios, simples (avec un seul agent porogène) ou combinés (avec un agent végétal et un agent de synthèse) ont été comparés avec la méthode ReCiPe. Les étapes présentant les impacts les plus importants ont été mises en exergue. Il a également été démontré que le choix de l’unité fonctionnelle pouvait modifier radicalement les conclusions de l’étude
The objective of this work is to develop new clay bricks with biobased pore-forming agents in order to obtain materials with high thermal performance. The raw materials, clay and biomass, were first characterized individually. The use of agricultural by-products (wheat straw, sunflower seed cake and olive stone flour) as pore-forming agents for the production of porous clay bricks was then studied. The benefits of the addition of biobased components that increase the porosity and the thermal resistance was demonstrated even if it results in a decrease of mechanical properties. However, problems of plasticity causing trouble during the extrusion of samples were identified. After optimizing the sand rate, the impact of the particle size of the biomass and the rate of incorporation were assessed. A maximum porosity of 34.4%, made up of macropores was obtained under optimal experimental conditions, leading to a thermal conductivity of 0.45 W/m.K, representing a decrease of 15 % compared to the reference brick without additive. In order to improve the properties of the resulting material, it was considered to create microporosity, thanks to the chemical modification of the vegetable materials that will be degraded during the firing process. For this, the agricultural by-products were modified either by direct impregnation of carbonates or by grafting of new chemical moieties (carbonate or ester). These modified matters were then incorporated into the clay formulation and the properties of the obtained bricks were measured (physical, mechanical and thermal ones). Finally, the potential environmental impact of the modified samples containing additives was studied through a Life Cycle Assessment. Different scenarios, simple (with one pore-forming agent) or combined (with a crude vegetable agent and a synthesized one) were compared with the ReCiPe method. The steps from the process with the most significant impacts were highlighted. It was also shown that the choice of the functional unit could radically alter the conclusions of the study
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8

Tavakkoli, Osgouei Yashar. "An Experimental Study On Steam Distillation Of Heavy Oils During Thermal Recovery." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615574/index.pdf.

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Thermal recovery methods are frequently used to enhance the production of heavy crude oils. Steam-based processes are the most economically popular and effective methods for heavy oil recovery for several decades. In general, there are various mechanisms over steam injection to enhance and have additional oil recovery. However, among these mechanisms, steam distillation plays pivotal role in the recovery of crude oil during thermal recovery process. In this study, an experimental investigation was carried out to investigate the role of various minerals present in both sandstone and carbonate formations as well as the effect of steam temperature on steam distillation process. Two different types of dead-heavy crude oils were tested in a batch autoclave reactor with 30 % water and the content of the reactor (crude oil, 10 % rock and mineral). The results were compared as the changes in the density, viscosity and chemical composition (SARA and TPH analyses) of heavy crude oil. Five different mineral types (bentonite, sepiolite, kaolinite, illite and zeolite) were added into the original crude oil and reservoir rocks to observe their effects on the rheological and compositional changes during steam distillation process. Analysis of the results of experiments with Camurlu and Bati Raman heavy crude oils in the presence of different minerals such as Bentonite, Zeolite, Illite, Sepiolite, and Kaolinite in both sandstone and limestone reservoir rocks indicate that steam distillation produces light end condensates which can be considered as solvent or condensate bank during steam flooding operation. It was also illustrated that minerals in reservoir formations perform the function of producing distilled light oil compounds, resulting in enhancement of heavy crude oils recovery in steam flooding. Measurements showed that the remaining oil after steam distillation has higher viscosity and density. On the other hand, the effect of steam distillation is more pronounced in limestone reservoirs compared to sandstone reservoirs for the given heavy crude oil and steam temperature. Among the five different minerals tested, kaolinite found to be the most effective mineral in terms of steam distillation.
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9

Santis, Bruno Carlos de. "Concretos leves com agregados inovadores de argila vermelha calcinada e subprodutos agroindustriais." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/74/74133/tde-22022017-105250/.

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Este trabalho tem por objetivo o estudo de concretos leves com agregados inovadores de argila vermelha calcinada e subprodutos agroindustriais. A argila utilizada na pesquisa foi caracterizada por meio das técnicas de limites de liquidez (LL) e plasticidade (LP), análise granulométrica, análise química e difração de raios X (DRX). Foram confeccionados corpos de prova de argila vermelha calcinada com incorporações de serragem de madeira, cinza do bagaço da cana-de-açúcar e silicato de sódio. Os corpos de prova de argila vermelha calcinada, queimados à temperatura de 900 °C, foram caracterizados por meio da avaliação da retração linear, absorção de água, porosidade aparente, massa específica aparente, expansão por umidade e resistência à compressão. Após a caracterização dos corpos de prova de argila vermelha calcinada, foram produzidos dois tipos de agregados, sendo o primeiro composto por 57% de argila e 43% de cinza do bagaço de cana-de-açúcar, conformados com água e silicato de sódio (proporção 1:1), e o segundo composto por 70% de argila e 30% de serragem de madeira. Os corpos de prova de concreto leve foram caracterizados pelos ensaios de slump, massa específica fresca, resistência à compressão, módulo de deformação, retração por secagem, absorção de água, índice de vazios e massa específica aparente e condutividade térmica. Os resultados desta pesquisa indicam a viabilidade da produção de agregados leves de argila vermelha calcinada com incorporações de subprodutos agroindustriais para utilização em concretos, uma vez que, mesmo com grande quantidade de utilização de subprodutos agroindustriais na produção dos agregados leves, os concretos produzidos com esses agregados apresentaram características similares aos concretos produzidos com agregados comerciais, apresentando um ganho econômico e energético significativo.
This paper aims to study lightweight concrete with innovative calcined clay lightweight aggregates made with agro-industrial by-products. The clay used in this research was characterized by techniques of liquid and plastic limits, particle size analysis, chemical analysis and X-ray diffraction (XRD). Calcined clay specimens were made with incorporations of wood sawdust, sugar cane ash and sodium silicate. These specimens, burned at a temperature of 900°C, were characterized by evaluating of linear shrinkage, water absorption, apparent porosity, specific mass, moisture expansion and compressive strength. After characterization of calcined clay specimens, two types of calcined clay lightweight aggregates with agro-industrial by-products were produced, wherein the first made with 57% of clay and 43% of sugar cane ash, mixed with water and sodium silicate (proportion 1:1) and the second made with 70% clay and 30% wood sawdust, mixed with water and burned at 900 °C. Specimens of lightweight concrete were characterized by slump test, fresh specific mass, compressive strength, modulus of elasticity, water absorption, voids and bulk density and thermal conductivity. Results of this research indicates the viability to produce calcined clay lightweight aggregates made with agro-industrial by-products to use in concrete, even using large amount of agro-industrial by-products, once concretes made with lightweight aggregates with agro-industrial by-products presented similar characteristics than those made with commercial aggregates, presenting significant energetic gain.
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10

BRENT, TAYLOR NICHOLAS. "The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/63663.

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[EN] ABSTRACT Nicholas Brent Taylor: The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material The bicycle is often considered as one of the most important inventions of all time. In addition, it is the most efficient form of human transport in the world. It is non pollutant, uses no fuel other than human power and its carbon footprint is neutralised in a short time. Today, faced with the threat of global warming brought about by fossil fuels, countries such as Denmark, the Netherlands and Columbia actually encourage the use of the bicycle as a viable means of urban transport, and in the city of Paris there are financial incentives for cycling commuters. In China alone there are 450 Million bicycles. The form of the bicycle is universally recognisable, it is easy to use and simple to maintain. However, in spite of its apparent simplicity, the bicycle is made up of numerous components and sub-assemblies. Over the years these components and sub-assemblies have undergone a succession of changes and modifications. As with the evolution, development, and life cycle of any product, some of the modifications were relatively short lived. Others for various reasons have been adopted almost universally, such as steel ball bearings, the roller chain, pneumatic tires, tension spoked wheels, etc. In order to more fully understand the bicycle, its advantages, its shortcomings, and its place in the modern world, the first part of this study aims to address the various criteria which apply to bicycle typology, differentiation, use and construction. However, although numerous types of Human Powered Vehicles (HPVs) exist, the initial part of this research is constrained to the evolution and development of the "Safety" type bicycle - attributed to J. K. Starley of Coventry in 1895 - up to the present day, taking into account such factors as; design, material selection, manufacturing technology, and diversity. The first part of the study is a comprehensive overview of the bicycle which identifies crucial technological aspects and categorises bicycle by type and intended use. Due to the huge quantities and types of bicycles produced worldwide this research identifies generic types of each category irrespective of origin or manufacturer. The second part of this dissertation is devoted to the study of wooden bicycles and the specific requirements of this type of bicycle such as the use of wood and its derivatives e.g. engineered wood, as a bicycle frame construction material and some of the solutions arrived at and the special parts or components required. Contemporary and historical bicycles made from wood, other organic material and its derivatives have been investigated and conclusions drawn regarding their functionality and purpose. Part three is dedicated to the Design, Development, and Evaluation of a Wooden Bicycle prototype undertaken by the Author with the assistance of three Industrial Design Students. Part four describes the design, construction and testing of subsequent prototypes in detail including the fabrication of pre-production bicycles and proposals for manufacture on a commercial level. Parts five and six outline the empirical findings from the previous section and attempt to define strategies for marketing bicycles manufactured from wood and its derivatives as an alternative to conventional materials with a view to reanimating small local industries which have a strong base of expertise and knowhow working with wood, such as producers of furniture and similar products (broom handles, tool handles, boxes etc.). Part seven is devoted to the potential diversification of wooden framed bicycles which are electrically assisted. The fabrication of a prototype is discussed but no conclusions were made due to constraints beyond my control. Keywords: Design, Product, Frame, Bicycle
[ES] RESUMEN Nicholas Brent Taylor: La Viabilidad de la Madera y sus Derivados como Material de Fabricación de Cuadros de Bicicletas La bicicleta es frecuentemente considerada como una de las invenciones más importantes de todos los tiempos. Es también una de las formas de transporte humano más eficiente en el mundo. Hoy en día, por la amenaza del calentamiento global provocado por las fuentes de energía no renovables, países como Dinamarca, Holanda y Colombia animan a usar la bicicleta como un medio de transporte urbano. La figura de la bicicleta es universalmente reconocida, es fácil de usar y su mantenimiento es simple. A pesar de su aparente simplicidad, la bicicleta está compuesta de numerosos componentes y subconjuntos. A lo largo de los años, los subconjuntos sufrieron una serie de cambios y transformaciones. Como en cualquier evolución y desarrollo, los cambios influyen en el ciclo de vida de cualquier producto, a pesar que algunas de estas aportaciones tuvieron una vida efímera. Otras, por razones varias, fueron adoptadas casi universalmente. Entre estas podemos citar los rodamientos de esferas de azor, la cadena, los neumáticos, etc. Para comprender mejor el producto bicicleta, se ha considerado como objetivo en la primera parte de este estudio, abordar varios criterios que se aplican de acuerdo con la tipología, diferenciación, uso y construcción de la bicicleta. A pesar de existir numerosos tipos de Human Powered Vehicles (HPVs), la primera parte de esta investigación se limita al estudio de la evaluación y desenvolvimiento de la bicicleta "Safety" atribuida A J.K. Starley de Coventry UK.1895, desde su aparición hasta nuestros días, tomando en consideración la selección de materiales, las tecnologías de fabricación, el diseño, y el estatus de la bicicleta en la sociedad. La segunda parte de esta tesis está dedicada por completo al estudio de la madera y sus derivados como material de construcción de la bicicleta. Bicicletas contemporáneas e históricas de madera y sus derivados, que han sido investigados y se han presentado los resultados en relación a su funcionalidad y propósito. La tercera parte describe con detalle el diseño, desarrollo y evaluación de una bicicleta prototipo de madera, los prototipos posteriores y las bicicletas prototipo o de pre-producción de madera y sus derivados fabricados por el autor con la ayuda de los Estudiantes finalistas del grado de Diseño Industrial (ESTGAD CR, Portugal) En la cuarta parte se describe el diseño, construcción y prueba de prototipos posteriores en detalle, incluyendo la fabricación de bicicletas de pre-producción y propuestas para la fabricación a nivel comercial. La quinta y sexto partes resume los resultados empíricos de la sección anterior y trata de definir estrategias de marketing, para bicicletas fabricadas a partir de la madera y sus derivados como una alternativa a los materiales convencionales, con el fin de animar a producción industrial a las pequeñas industrias locales, que poseen una base sólida de experiencia en el trabajo con la madera, como productores de muebles y productos similares. En la última parte, se ha dedicado a la diversificación potencial de cuadros de bicicletas en madera que están asistidas eléctricamente. La fabricación de un prototipo forma parte de la discusión y pretende ser una proyección de futuro. Palabras Clave: Diseño, Producto, Madera, Bicicleta.
[CAT] RESUM Nicholas Brent Taylor: La Viabilitat de la Fusta i els seus Derivats com Material de Fabricacio de Quadros de Bicicletes La bicicleta es freqüentment considerada com una de les invencions mes importants de tots els temps. Es tambe una de les formes de transport huma mes eficient en el mon. Hui en dia, per l'amenaça del calfament global provocat per les fonts d'energia no renovellables, països com Dinamarca, Holanda i Colombia animen a usar la bicicleta com un mig de transport urba. La figura de la bicicleta es universalment reconeguda, es facil d'usar i el seu manteniment es simple. A pesar de la seua aparent simplicitat, la bicicleta està composta de numerosos components i subconjuntos. A lo llarc dels anys, els subconjuntos patiren una serie de canvis i transformacions. Com en qualsevol evolucio i desenroll, els canvis influixen en el cicle de vida de qualsevol producte, a pesar que algunes d'estos aportaments tingueren una vida efimera. Atres, per raons varies, foren adoptades casi universalment. Entre estes podem citar els rodaments d'esferes d'azor, la cadena, els neumatics, etc. Per a comprendre millor el producte bicicleta, s'ha considerat com objectiu en la primera part d'este estudi, abordar varis criteris que s'apliquen d'acort en la tipología, diferenciacio, us i construccio de la bicicleta. A pesar d'existir numerosos tipos d'Human Powered Vehicles (HPVS), la primera part d'esta investigacio se llimita a l'estudi de l'evaluacio i desenvolupament de la bicicleta "Safety" atribuida A J.K. Starley de Coventry UK. 1895, des de la seua aparicio fins nostres dies, prenent en consideracio la seleccio de materials, les tecnologies de fabricacio, el disseny, i l'estat de la bicicleta en la societat. La segona part d'esta tesis està dedicada per complet a l'estudi de la fusta i els seus derivats com material de construccio de la bicicleta. Bicicletes contemporanees i historiques de fusta i els seus derivats, que han segut investigats i s'han presentat els resultats en relacio a la seua funcionalitat i proposit. La tercera part descriu en detall el disseny, desenroll i evaluacio d'una bicicleta prototip de fusta, els prototips posteriors i les bicicletes prototip o de PRE-produccio de fusta i els seus derivats fabricats per l'autor en l'ajuda dels Estudiants finalistes del grau de Disseny Industrial (ESTGAD CR, Portugal) En la quarta part se descriu el disseny, construccio i prova de prototips posteriors en detall, incloent la fabricacio de bicicletes de pre-produccio i propostes per a la fabricacio a nivell comercial. La quinta i sisè parts resumix els resultats empirics de la seccio anterior i tracta de definir estrategies de marketing, per a bicicletes fabricades a partir de la fusta i els seus derivats com una alternativa als materials convencionals, en el fi d'animar a produccio industrial a les menudes industries locals, que posseixen una base solida d'experiencia en el treball en la fusta, com productors de mobles i productes similars. En l'ultima part, s'ha dedicat a la diversificacio potencial de quadros de bicicletes en fusta que estan assistides electricament. La fabricacio d'un prototip forma part de la discussio i preten ser una proyeccio de futur. Paraules Clau: Disseny, Producte, Fusta, Bicicleta.
Brent Taylor, N. (2016). The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63663
TESIS
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Sales, J?nior Jos? Carlos Calado. "Avalia??o da potencialidade de argilas de queima clara como mat?rias-primas para o desenvolvimento de novos produtos cer?micos." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15550.

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The industries of structural ceramics are among the most important production chains in the state of Rio Grande do Norte. The industry and other interest groups to target the replacement of firewood by natural gas. Studies accordingly concluded that simple change does not guarantee products of superior quality, and that the increase in spending on fuel can economically cripple the use of gas for burning the majority of products manufactured by that action. However some proposals of innovations in terms of process and product are being studied in an attempt to justify the use of natural gas in industry, structural ceramics. One of the aspects investigated is the development of ceramic products differentiated, with new designs and greater value added. Inserted in that context, this paper aims to investigate the potential use of clay-firing clear fabrication of the "bricks of apparent joins drought", a new ceramic product with an innovative way. The development of the work was done in three stages. In the initial stage was held the characterization of raw materials, sought information on physical, chemical, mineralogical and mechanical samples. In the second stage five bodies were made using two of the nine ceramic clay characterized the first step. The masses were analyzed and compared with respect to the size distribution, plasticity and technological properties. In the last part of this work was carried out tests on massive bricks manufactured on an industrial scale. The results show that the nine clays can be used in the manufacture of new ceramic products, is the only constituent of mass ceramic or by mixing with other(s) clay(s
As ind?strias de cer?mica estrutural figuram entre as cadeias produtivas mais importantes do estado do Rio Grande do Norte. O setor e outros grupos de interesse almejam a substitui??o da lenha pelo g?s natural. Estudos realizados nesse sentido conclu?ram que a simples mudan?a n?o garante produtos de qualidade superior, e que o aumento no gasto com combust?vel pode inviabilizar economicamente o uso do g?s para queima da maioria dos produtos fabricados por esse seguimento. Entretanto algumas propostas de inova??es em termos de processo e produto v?m sendo estudadas na tentativa de justificar o uso do g?s natural na ind?stria de cer?mica estrutural. Uma das vertentes pesquisadas ? o desenvolvimento de produtos cer?micos diferenciados, com novos designs e maior valor agregado. Inserido nesse contexto, o presente trabalho tem como objetivo investigar a potencialidade do uso de argilas de queima clara para fabrica??o dos tijolos de junta seca , um novo produto cer?mico com forma inovadora. O desenvolvimento do trabalho foi efetuado em tr?s etapas. Na etapa inicial foi realizada a caracteriza??o das mat?rias-primas, buscando obter informa??es em rela??o ?s propriedades f?sicas, qu?micas, mineral?gicas e mec?nicas das amostras. Na segunda etapa foram formuladas cinco massas cer?micas utilizando duas das nove argilas caracterizadas na primeira etapa. As massas foram analisadas e comparadas em rela??o ? distribui??o granulometria, plasticidade e propriedades tecnol?gicas. Na ?ltima parte desse trabalho foi realizado testes em tijolos maci?os fabricados em escala industrial. Os resultados mostram que as nove argilas podem ser utilizadas na fabrica??o dos novos produtos cer?micos, seja como ?nica constituinte da massa cer?mica ou pela mistura com outra(s) argila(s)
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12

Tonini, Federico. "Bioconcentration of selected personal care products in Ruditapes philippinarum (Manila clam)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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The Bioconcentration Factor (BCF) is the principal source of information used to assess and regulate the potential hazard and risk for a chemical that has the potential to bioaccumulate in the marine environment, according to the Marine Strategy Framework Directive (MSFD). The main objective of this thesis was to estimate the BCFs of two different emerging contaminants in Ruditapes philippinarum (Manila clam) under controlled laboratory conditions: the UV filter 4-methylbenzylidene camphor (4-MBC) commonly used in skincare products, and the artificial sweetener Acesulfame potassium (ACE-K) used as a food additive. Ruditapes philippinarum organisms were exposed directly to 4-MBC and ACE-K nominal concentration of 1, 10 and 100 μg L-1 during 10 days. Bioconcentration factors (BCFs) were estimated according to 3 different models for both compounds. The 4-MBC estimated BCFs fall in range of 61553 - 539143 L Kg-1, showing that this compound is very bioaccumulative and could also undergo biomagnification in the marine food chain. On the contrary, estimated ACE-K BCF is consistently lower, in order of 7 L Kg-1 for the nominal exposure concentration of 100 μg L-1. The low ACE-K BCF could be explained by its high solubility in water and thus a rapid metabolization by clams during the experiments. In summary, future research focusing on the marine environment is needed on these two emerging compounds.
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13

Libelo, Edward Laurence. "Characterization, utilization and treatment of mechanized clam processing wastes." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80072.

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In response to water quality deterioration caused by clam processing effluent, the Virginia State Water Control Board is imposing much greater effluent discharge limitations on the industry. Meeting these limits will require increased wastewater treatment and decreasing the water volume of water used and the loading of organic material and suspended solids. Disposal of sludges and solid wastes also present problems to the industry. Three processing plants were studied to characterize the nature, sources and variations in waste generation and to evaluate potential solutions. Wastewater is generated throughout the processing plants from washing operations, from splashing and overflow of tanks and flumes and from cleanup operations. Wastewater generation varied from plant to plant and at each plant over time, ranging from 80,000 gallons to almost 350,000 gallons per day and as high as 40,000 gallons per hour. The organic loading in wastewater ranged as high as 15,000 mg/L COD and averaged 3000-7000 mg/L. Total suspended solids loading ranged as high as 29,000, and were usually between 1,000 and 10,000 mg/L. Anaerobic digestion and composting of solid wastes were evaluated by bench scale experiments. Anaerobic digestion can provide reduction in COD of 75% and generate usable biogas. Composting can be used to stabilize sludges and solid wastes with destruction of the organic fraction in seven days. The proposed 90 mg/L BOD and 90 mg/L TSS limitations are not significantly stricter than the limitations imposed on similar plants in other areas.
Master of Science
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14

Matos, Alice Tereza Sampaio de. "Detecção in silico dos constituintes majoritários de Strychnos brasiliensis e S. pseudoquina (Loganiaceae) usando CLAE-DAD/EMAR /." Araraquara : [s.n.], 2009. http://hdl.handle.net/11449/97969.

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Orientador: Ian Castro-Gamboa
Banca: Lucia Xavier Lopes
Banca: Maria Inês Genovese Rodriguez
Resumo: O Núcleo de Bioensaios, Biossíntese e Ecofisiologia de Produtos Naturais (NuBBE) condensa, em suas atividades de pesquisa, o estudo de micromoléculas bioativas provenientes de plantas do Cerrado e Mata Atlântica Paulistas. Nos últimos anos o NuBBE investe no desenvolvimento de metodologias analíticas de derreplicação, utilizando diversas técnicas acopladas, tais como, CLAE/DEQ-DAD, EMAR/CLAE-DAD e EM/CLAE-DAD, para acelerar a escolha de extratos vegetais brutos. Técnicas analíticas de detecção in silico vêm sendo incorporadas às metodologias cromatográficas de construção de perfis micromoleculares, auxiliando na seleção apenas dos metabólitos de interesse presentes em matrizes brutas. Nesta dissertação foi abordado o estudo dos extratos de Strychnos brasiliensis e S. pseudoquina (Loganiaceae) através de bioensaios de atividade antioxidante e de inibição de polimerização da hematina. Esses bioensaios revelaram a fração acetato de etila, dos galhos de S. brasiliensis, como matriz promissora em ambos os testes assim como os galhos de S. pseudoquina com potencial atividade antioxidante. A fração acetato de etila dos galhos de S. brasiliensis e o extrato bruto das folhas de S. pseudoquina foram avaliados fazendo uso da técnica hifenada EMAR/CLAE-DAD. Como resultado desta análise, quatro micromoléculas foram elucidadas: a 10- hidroxi-17-O-metilacagerina para as folhas de S. pseudoquina, estricnohirsutina, 14,15,16-trinor-11-labden-13,8-oleído e acagerina para a fração acetato de etila dos galhos de S. brasiliensis. Além disso, foi construída uma base de dados que reúne algumas informações físico-químicas e espectroscópicas valiosas, ajudando na detecção e isolamento das substâncias presentes nas duas espécies de Strychnos, objeto do nosso estudo.
Abstract: The Nuclei of Bioassays, Biosynthesis and Natural Products Ecophysiology (NuBBE) condenses in their research activities, the study of bioactive micromolecules from plants of the Cerrado and Atlantic Forest from São Paulo's State. In recent years, NuBBE has increased efforts in the development of analytical dereplication methods using various coupled techniques such as HPLC/DAD-ECD, EMAR/DAD and HPLC-MS/HPLC-DAD, to speed-up the selection of crude plant extracts. In silico analytical techniques have been incorporated into chromatographic methodologies aiming to build micromolecular profiles, assisting in the selection only of metabolites of interest in crude matrixes. This dissertation aims the study of extracts from Strychnos brasiliensis and Strychnos pseudoquina (Loganiaceae) throughout bioassays of antioxidant activity and inhibition of polymerization of heme, which showed the ethyl acetate fraction from branches of S. brasiliensis, as a promising matrix in both in vitro tests as well as the branches of S. pseudoquina that showed potential antioxidant properties. The ethyl acetate fraction from Strychnos brasiliensis branches and the crude extract from leaves of Strychnos pseudoquina were evaluated using HRMS/HPLC-DAD. From that analysis, four structures have been elucidated: 10-hydroxy-17-O-methylakagerine, from leaves of S. pseudoquina, strychnohirsutine, 14,15,16-trinor-11-labden-13,8-olide and akagerine from the ethyl acetate fraction of branches from S. brasiliensis. In addition, we have built up a database that gathers information about the structures detected in this study, such as molecular weight, structure, molecular formula, mass spectrum, aiming to facilitate the structural as well as the total elucidation of molecules of interest.
Mestre
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15

Lorentz, Romain. "Formalisation d'un modèle de conception et d'innovation dans le domaine des bio-industries : cas des particules d'argile." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0039/document.

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Cette thèse de doctorat a été menée dans le cadre d'un partenariat entre le Laboratoire Conception de Produits et Innovation des Arts et Métiers ParisTech et l'Ecole de Biologie Industrielle. Le projet de recherche porteur de nos travaux de thèse vise à accompagner la valorisation de nouvelles particules d'argile ayant fait l'objet d'un dépôt de brevet au sein du laboratoire EBInnov®. Ce nouvel ingrédient polyfonctionnel est destiné à satisfaire de multiples applications dans les secteurs bio-industriels, notamment dans l'industrie pharmaceutique, le secteur des cosmétiques, le phytosanitaire ou encore l'environnement. L'objectif de nos travaux de thèse est d'intégrer les spécifications techniques, sensorielles et réglementaires des entreprises de ces secteurs au sein d'un modèle de conception axé innovation. Pour ce faire, les hypothèses de recherche s'appuient sur l'émergence du paradigme de l'innovation ouverte dans ces secteurs. Nous soutenons que les nouveaux intermédiaires de l'innovation sont performants dans les bio-industries et permettent la prise en compte du potentiel d'innovation dès les phases amont du processus de conception. La validité de ces hypothèses a ensuite été vérifiée en milieu industriel par le biais d'expérimentations en lien direct avec les secteurs d'application de la technologie EBISilc®. Finalement, nous proposons un modèle de conception axé innovation prenant en compte l'évolution des modèles d'innovation dans les bio-industries
This doctoral thesis was realized within the framework of a partnership between the Product Design and Innovation Laboratory of Arts et Métiers ParisTech and the Ecole de Biologie Industrielle. The research project behind our thesis aims to support the promotion of new clay particles having been patented by the EBInnov® laboratory. This new polyfunctional ingredient is designed to satisfy several applications in the bio-industries, including the pharmaceutical and cosmetic industry, the phytosanitary sector or the environment. The aim of the thesis is to integrate the technical, sensory and regulatory specifications of bio-industrial companies in an innovation-oriented design process. Thus, the research hypotheses rely on the emerging paradigm of open innovation in these sectors. We support that the new innovation intermediaries are efficient in the bio-industries and allow the integration of the innovation potential in the early stages of the design process. The validity of these assumptions was studied by means of industry-related experiments directly linked to the main application sectors of the EBISilc® technology. Finally, we propose an innovation-oriented design process taking into account the evolution of the innovation models in the bio-industries
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16

Queiroz, Marcos Marçal Ferreira [UNESP]. "Utilização da técnica hifenada CLAE-DAD-IES-EM na detecção e caracterização de substâncias em Ocotea paranapiacabensis e Aniba firmula (Lauraceae)." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/97955.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho apresenta a aplicação da metodologia de análise in silico em frações da partição líquido-líquido obtidas a partir do extrato hidroalcoólico das folhas de Ocotea paranapiacabensis e Aniba firmula (Lauraceae). A abordagem utilizou os dados obtidos a partir da técnica hifenada CLAE-DAD-IES-EM, sendo esses dados analisados e contrastados com a base de dados do Dictionary of Natural Products (DNP), a fim de se detectar metabólitos secundários previamente isolados nos gêneros Ocotea e Aniba. A partir da obtenção desses dados, foi possível direcionar o estudo das frações analisadas para a identificação de novas substâncias nos gêneros estudados. Utilizando a metodologia, foram detectadas, estruturas isoméricas de alcalóides aporfinóides e dois flavonóides monoglicosilados nas folhas de O. paranapiacabensis. Não há relatos desses flavonóides em espécies do gênero Ocotea, o que levou ao planejamento de uma estratégia para o isolamento desses constituintes, que tiveram sua estrutura elucidada através da análise de RMN 1H e 13C. A abordagem utilizada no estudo da fração acetato de etila das folhas de A. firmula possibilitou a detecção de quatro substâncias da classe das estirilpironas (1- 4), esses dados foram importantes para a obtenção de uma região específica do perfil cromatográfico CLAE-DAD onde não foram detectados substâncias previamente isoladas através da análise in silico. A fração AFFAc foi então submetida a CLAE-UV com a finalidade de identificar novos constituintes químicos (estirilpironas). A fração obtida foi analisada e purificada, resultando no isolamento de dímeros de estirilpironas inéditos na literatura, 4-metoxi-8`-(11`,12`- metilenodioxifenil)-7-[6-(4-metoxi-2-pironil)]-6`-estiril-oxabiciclo[4,2,0]-ocat-4`-em-2`- ona (5) 8`-(11`, 12`metilenodioxifenil)-8-fenil-7,7` di [6-(4,4`-dimetoxi-piran-2-ona) ciclobutano...
This work presents the application of the methodology in silico in partition liquid-liquid fractions obtained from the hydroalcoholic extract of leaves of Ocotea paranapiacabensis and Aniba firmula (Lauraceae). The approach used the data obtained from the hyphenated technique HPLC-DAD-ESI-MS, these data are analyzed and contrasted with the database of the Dictionary of Natural Products (DNP) in order to detect secondary metabolites previously isolated in the genus Ocotea and Aniba. Upon obtaining these data, it was possible to direct the study of fractions analyzed to the identification of new substances in the genera studied. Using the methodology, were detected, isomeric structures of aporphinic alkaloids and two flavonoids in leaves of O. paranapiacabensis. There are no reports of these flavonoids in species of the genus Ocotea, which led to planning a strategy for the isolation of these constituents, which had its structure elucidated by analysis of 1H and 13C NMR. The approach used in the study of the ethyl acetate fraction of leaves of A. firmula enabled the detection of four substances of styrilpyrones class (1-4), these data were important for determination a specific region of the HPLC-DAD chromatographic profile which were not detected substances previously isolated by in silico analysis. The fraction AFFAc was then subjected to HPLC-UV with the aim of identifying new chemical constituents (styrilpyrones). The fraction obtained was analyzed and purified, resulting in the isolation of dimers of estirilpironas unprecedented in the literature, 4-methoxy-8 `- (11`, 12 `-metilenodioxiphenyl) -7 - [6 - (4-methoxy-2-pironil) ] -6 `-styryl-oxabicyclo [4,2,0]-ocat-4`-at-`2-one (5) 8` - (11 `, 12` metilenodioxiphenyl)-8-phenyl-7, 7`- di [6 - (4,4 -dimethoxy-pyran-2-one) ciclobutane (6), confirming the importance of application of in silico analysis as a tool for the identification of chemical constituents in the already described species.
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17

Queiroz, Marcos Marçal Ferreira. "Utilização da técnica hifenada CLAE-DAD-IES-EM na detecção e caracterização de substâncias em Ocotea paranapiacabensis e Aniba firmula (Lauraceae) /." Araraquara : [s.n.], 2009. http://hdl.handle.net/11449/97955.

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Resumo: Este trabalho apresenta a aplicação da metodologia de análise in silico em frações da partição líquido-líquido obtidas a partir do extrato hidroalcoólico das folhas de Ocotea paranapiacabensis e Aniba firmula (Lauraceae). A abordagem utilizou os dados obtidos a partir da técnica hifenada CLAE-DAD-IES-EM, sendo esses dados analisados e contrastados com a base de dados do Dictionary of Natural Products (DNP), a fim de se detectar metabólitos secundários previamente isolados nos gêneros Ocotea e Aniba. A partir da obtenção desses dados, foi possível direcionar o estudo das frações analisadas para a identificação de novas substâncias nos gêneros estudados. Utilizando a metodologia, foram detectadas, estruturas isoméricas de alcalóides aporfinóides e dois flavonóides monoglicosilados nas folhas de O. paranapiacabensis. Não há relatos desses flavonóides em espécies do gênero Ocotea, o que levou ao planejamento de uma estratégia para o isolamento desses constituintes, que tiveram sua estrutura elucidada através da análise de RMN 1H e 13C. A abordagem utilizada no estudo da fração acetato de etila das folhas de A. firmula possibilitou a detecção de quatro substâncias da classe das estirilpironas (1- 4), esses dados foram importantes para a obtenção de uma região específica do perfil cromatográfico CLAE-DAD onde não foram detectados substâncias previamente isoladas através da análise in silico. A fração AFFAc foi então submetida a CLAE-UV com a finalidade de identificar novos constituintes químicos (estirilpironas). A fração obtida foi analisada e purificada, resultando no isolamento de dímeros de estirilpironas inéditos na literatura, 4-metoxi-8'-(11',12'- metilenodioxifenil)-7-[6-(4-metoxi-2-pironil)]-6'-estiril-oxabiciclo[4,2,0]-ocat-4'-em-2'- ona (5) 8'-(11', 12'metilenodioxifenil)-8-fenil-7,7' di [6-(4,4'-dimetoxi-piran-2-ona) ciclobutano... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work presents the application of the methodology in silico in partition liquid-liquid fractions obtained from the hydroalcoholic extract of leaves of Ocotea paranapiacabensis and Aniba firmula (Lauraceae). The approach used the data obtained from the hyphenated technique HPLC-DAD-ESI-MS, these data are analyzed and contrasted with the database of the Dictionary of Natural Products (DNP) in order to detect secondary metabolites previously isolated in the genus Ocotea and Aniba. Upon obtaining these data, it was possible to direct the study of fractions analyzed to the identification of new substances in the genera studied. Using the methodology, were detected, isomeric structures of aporphinic alkaloids and two flavonoids in leaves of O. paranapiacabensis. There are no reports of these flavonoids in species of the genus Ocotea, which led to planning a strategy for the isolation of these constituents, which had its structure elucidated by analysis of 1H and 13C NMR. The approach used in the study of the ethyl acetate fraction of leaves of A. firmula enabled the detection of four substances of styrilpyrones class (1-4), these data were important for determination a specific region of the HPLC-DAD chromatographic profile which were not detected substances previously isolated by in silico analysis. The fraction AFFAc was then subjected to HPLC-UV with the aim of identifying new chemical constituents (styrilpyrones). The fraction obtained was analyzed and purified, resulting in the isolation of dimers of estirilpironas unprecedented in the literature, 4-methoxy-8 '- (11', 12 '-metilenodioxiphenyl) -7 - [6 - (4-methoxy-2-pironil) ] -6 '-styryl-oxabicyclo [4,2,0]-ocat-4'-at-'2-one (5) 8' - (11 ', 12' metilenodioxiphenyl)-8-phenyl-7, 7'- di [6 - (4,4 "-dimethoxy-pyran-2-one) ciclobutane (6), confirming the importance of application of in silico analysis as a tool for the identification of chemical constituents in the already described species.
Orientador: Vanderlan da Silva Bolzani
Coorientador: Ian Castro-Gamboa
Banca: Alberto José Cavalheiro
Banca: Patrícia Mendonça Pauletti
Mestre
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18

CICOGNINI, FRANCESCA MARIA. "CLA as a nutraceutical molecule: concentration in foods, estimation of intake in Italy and genetic factors affecting thesynthesis in animal tissue." Doctoral thesis, Università Cattolica del Sacro Cuore, 2014. http://hdl.handle.net/10280/2467.

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Gli isomeri del CLA (Acido Linoleico Coniugato) potrebbero avere effetti benefici sulla salute in relazione al raggiungimento di un determinato intake, ma, per quanto ci è dato sapere, non esiste letteratura in Italia riguardante l'effettiva quantità di CLA negli alimenti e al relativo intake nell'uomo. Quindi è stata condotta una quantificazione degli isomeri c9,t11 e t10,c12 negli alimenti disponibili sul mercato italiano, seguita da una stima dell'intake di questi isomeri in una coorte della popolazione italiana attraverso un diario alimentare. Lo step successivo del progetto di ricerca, dovuto al livello molto basso di CLA trovato negli alimenti, è stato di investigare i fattori genetici che influenzano il CLA nella carne, per poter aumentare la concentrazione finale di CLA per il consumatore finale. Quindi gli obiettivi del lavoro sono stati: la stima dell'effettivo intake di CLA in Italia attraverso una completa analisi della concentrazione di c9,t11 e t10,c12 nei prodotti lattiero-caseari e carnei comunemente disponibili, e una valutazione dei fattori genetici coinvolti nella sintesi di CLA nella carne.
CLA could exert some healthy properties in relation to a needed daily intake, but, at our knowledge, no literature in Italy is currently available on the effective CLA amount in foods and on the relative intake in humans. Thus a quantification of c9,t11 and t10,c12 CLA isomers in foods available in Italy large retail-scale trade was performed, followed by an estimation of the isomers intake in a cohort of the Italian population by a food diary. Background 6 The following step of the research project, due to the very low concentration of CLA found in foods, investigated genetic factors affecting CLA in meat, in order to enhance its concentration for final consumers. Thus the aims of the present work were to estimate the effective CLA intake in Italy through a complete analisys of c9,t11 and t10,c12 concentrations in dairy and meat products commonly purchasable, and an evaluation on the genetic factors involved in CLA synthesis in meat.
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19

Mahesha, Chaitra. "Investigation of structure and properties of novel multi-layer clay nanocomposite films produced controllably by continuous chaotic advection blending." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1202501538/.

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20

Matos, Alice Tereza Sampaio de [UNESP]. "Detecção in silico dos constituintes majoritários de Strychnos brasiliensis e S. pseudoquina (Loganiaceae) usando CLAE-DAD/EMAR." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/97969.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O Núcleo de Bioensaios, Biossíntese e Ecofisiologia de Produtos Naturais (NuBBE) condensa, em suas atividades de pesquisa, o estudo de micromoléculas bioativas provenientes de plantas do Cerrado e Mata Atlântica Paulistas. Nos últimos anos o NuBBE investe no desenvolvimento de metodologias analíticas de derreplicação, utilizando diversas técnicas acopladas, tais como, CLAE/DEQ-DAD, EMAR/CLAE-DAD e EM/CLAE-DAD, para acelerar a escolha de extratos vegetais brutos. Técnicas analíticas de detecção in silico vêm sendo incorporadas às metodologias cromatográficas de construção de perfis micromoleculares, auxiliando na seleção apenas dos metabólitos de interesse presentes em matrizes brutas. Nesta dissertação foi abordado o estudo dos extratos de Strychnos brasiliensis e S. pseudoquina (Loganiaceae) através de bioensaios de atividade antioxidante e de inibição de polimerização da hematina. Esses bioensaios revelaram a fração acetato de etila, dos galhos de S. brasiliensis, como matriz promissora em ambos os testes assim como os galhos de S. pseudoquina com potencial atividade antioxidante. A fração acetato de etila dos galhos de S. brasiliensis e o extrato bruto das folhas de S. pseudoquina foram avaliados fazendo uso da técnica hifenada EMAR/CLAE-DAD. Como resultado desta análise, quatro micromoléculas foram elucidadas: a 10- hidroxi-17-O-metilacagerina para as folhas de S. pseudoquina, estricnohirsutina, 14,15,16-trinor-11-labden-13,8-oleído e acagerina para a fração acetato de etila dos galhos de S. brasiliensis. Além disso, foi construída uma base de dados que reúne algumas informações físico-químicas e espectroscópicas valiosas, ajudando na detecção e isolamento das substâncias presentes nas duas espécies de Strychnos, objeto do nosso estudo.
The Nuclei of Bioassays, Biosynthesis and Natural Products Ecophysiology (NuBBE) condenses in their research activities, the study of bioactive micromolecules from plants of the Cerrado and Atlantic Forest from São Paulo’s State. In recent years, NuBBE has increased efforts in the development of analytical dereplication methods using various coupled techniques such as HPLC/DAD-ECD, EMAR/DAD and HPLC-MS/HPLC-DAD, to speed-up the selection of crude plant extracts. In silico analytical techniques have been incorporated into chromatographic methodologies aiming to build micromolecular profiles, assisting in the selection only of metabolites of interest in crude matrixes. This dissertation aims the study of extracts from Strychnos brasiliensis and Strychnos pseudoquina (Loganiaceae) throughout bioassays of antioxidant activity and inhibition of polymerization of heme, which showed the ethyl acetate fraction from branches of S. brasiliensis, as a promising matrix in both in vitro tests as well as the branches of S. pseudoquina that showed potential antioxidant properties. The ethyl acetate fraction from Strychnos brasiliensis branches and the crude extract from leaves of Strychnos pseudoquina were evaluated using HRMS/HPLC-DAD. From that analysis, four structures have been elucidated: 10-hydroxy-17-O-methylakagerine, from leaves of S. pseudoquina, strychnohirsutine, 14,15,16-trinor-11-labden-13,8-olide and akagerine from the ethyl acetate fraction of branches from S. brasiliensis. In addition, we have built up a database that gathers information about the structures detected in this study, such as molecular weight, structure, molecular formula, mass spectrum, aiming to facilitate the structural as well as the total elucidation of molecules of interest.
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21

Ropero, Denise Ricoy [UNESP]. "Detecção in silico e caracterização estrutural dos constituintes micromoleculares majoritários presentes no fungo endofitico Phomopsis stipata isolado de folhas de Styrax camporum Pohl (Styracaceae) usando CLAE-DAD/EMAR e CG-MS." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/97979.

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No trabalho foi abordado o estudo de extratos do fungo Phomopsis stipata cultivado em diferentes meios de cultura na implementação da metodologia in silico utilizando cromatografia gasosa acoplada à espectrometria de massas e cromatografia líquida de alta eficiência acoplada à espectrometria de massas de alta resolução conjugados com a base de dados do dicionário de produtos naturais (http://dnp.chemnetbase.com). Foi realizada a comparação da diversidade na produção metabólica do fungo endofítico quando cultivado em diferentes meios de cultura comerciais e em cereal (milho), através do perfil cromatográfico, assim como avaliação das atividades antioxidante e propriedades de inibição da polimerização do heme. Nos extratos diclorometânicos foram identificadas oito substâncias. No extrato diclorometânico do fungo endofítico, crescido em milho, cinco substâncias foram detectadas, sendo elas: 1- derivado -lactônico; 2- ácido n-hexadecanóico; 3- ácido 16-octadecanóico; 4- di-hexanoato de 2-etilhexila e 5- hexadecanoato de iso-propilodiol. E, para o extrato diclorometânico de P. stipata, crescido em meio batata dextrose, três substâncias foram detectadas, dentre elas: 6- ciclohexen-2-ol- 3,5,5-trimetil-ona; 7- hexahidropirrolol [1,2-a] pirazina-1,4-diona-3-benzil e 8- hexahidropirrolol [1,2-a] pirazina-1,4-diona-3-isometil. O emprego de CLAE-DAD-EM e espectrometria de massas tandem possibilitou a identificação, diretamente a partir dos extratos brutos do fungo, de seis substâncias que já foram relatadas para outras espécies do gênero Phomopsis e duas substâncias já antes identificadas na espécie Phomopsis stipata, totalizando oito substâncias detectadas. Para o extrato acetato de etila, crescido em extrato de malte, no modo estático, três substâncias foram detectadas, sendo elas: 10- phomopsidina; 11- phomopsilactona e 12- phomosina...
This work show the study of extracts of the fungus Phomopsis stipata grown in different culture broth in the implementation of in silico methods using gas chromatography coupled to mass spectrometry and high performance liquid chromatography coupled to mass spectrometer for high resolution, combined with the database dictionary of natural products (http://dnp.chemnetbase.com). A comparison of diversity in the metabolic production of endophytic fungus when grown in different culture broth and cereal (corn) by the chromatographic profile was made, as well as assessment of activities of antioxidant properties and inhibition of heme polymerization. In dichloromethane extracts eight substances were identified. In dichloromethane extract of the endophytic fungus, grown in corn, five substances were detected, which were: 1- -lactone derivative; 2- n-hexadecanoic acid; 3- 16- octadecenoic acid; 4- hexanedioic acid, bis(2-ethylhexyl) ester and 5- hexadecanoic acid, 2-hydroxy-1-(hydroxymetil)ethyl ester, And for the dichloromethane extract of P. stipata, grown on potato dextrose broth, three substances were detected, among them:... (Complete abstract click electronic access below)
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22

Ropero, Denise Ricoy. "Detecção in silico e caracterização estrutural dos constituintes micromoleculares majoritários presentes no fungo endofitico Phomopsis stipata isolado de folhas de Styrax camporum Pohl (Styracaceae) usando CLAE-DAD/EMAR e CG-MS /." Araraquara : [s.n.], 2009. http://hdl.handle.net/11449/97979.

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Resumo: No trabalho foi abordado o estudo de extratos do fungo Phomopsis stipata cultivado em diferentes meios de cultura na implementação da metodologia in silico utilizando cromatografia gasosa acoplada à espectrometria de massas e cromatografia líquida de alta eficiência acoplada à espectrometria de massas de alta resolução conjugados com a base de dados do dicionário de produtos naturais (http://dnp.chemnetbase.com). Foi realizada a comparação da diversidade na produção metabólica do fungo endofítico quando cultivado em diferentes meios de cultura comerciais e em cereal (milho), através do perfil cromatográfico, assim como avaliação das atividades antioxidante e propriedades de inibição da polimerização do heme. Nos extratos diclorometânicos foram identificadas oito substâncias. No extrato diclorometânico do fungo endofítico, crescido em milho, cinco substâncias foram detectadas, sendo elas: 1- derivado -lactônico; 2- ácido n-hexadecanóico; 3- ácido 16-octadecanóico; 4- di-hexanoato de 2-etilhexila e 5- hexadecanoato de iso-propilodiol. E, para o extrato diclorometânico de P. stipata, crescido em meio batata dextrose, três substâncias foram detectadas, dentre elas: 6- ciclohexen-2-ol- 3,5,5-trimetil-ona; 7- hexahidropirrolol [1,2-a] pirazina-1,4-diona-3-benzil e 8- hexahidropirrolol [1,2-a] pirazina-1,4-diona-3-isometil. O emprego de CLAE-DAD-EM e espectrometria de massas tandem possibilitou a identificação, diretamente a partir dos extratos brutos do fungo, de seis substâncias que já foram relatadas para outras espécies do gênero Phomopsis e duas substâncias já antes identificadas na espécie Phomopsis stipata, totalizando oito substâncias detectadas. Para o extrato acetato de etila, crescido em extrato de malte, no modo estático, três substâncias foram detectadas, sendo elas: 10- phomopsidina; 11- phomopsilactona e 12- phomosina... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work show the study of extracts of the fungus Phomopsis stipata grown in different culture broth in the implementation of in silico methods using gas chromatography coupled to mass spectrometry and high performance liquid chromatography coupled to mass spectrometer for high resolution, combined with the database dictionary of natural products (http://dnp.chemnetbase.com). A comparison of diversity in the metabolic production of endophytic fungus when grown in different culture broth and cereal (corn) by the chromatographic profile was made, as well as assessment of activities of antioxidant properties and inhibition of heme polymerization. In dichloromethane extracts eight substances were identified. In dichloromethane extract of the endophytic fungus, grown in corn, five substances were detected, which were: 1- -lactone derivative; 2- n-hexadecanoic acid; 3- 16- octadecenoic acid; 4- hexanedioic acid, bis(2-ethylhexyl) ester and 5- hexadecanoic acid, 2-hydroxy-1-(hydroxymetil)ethyl ester, And for the dichloromethane extract of P. stipata, grown on potato dextrose broth, three substances were detected, among them:... (Complete abstract click electronic access below)
Orientador: Ian Castro-Gamboa
Coorientador: Ângela Regina Araújo
Banca: Miriam Sannomiya
Banca: Luce Maria Brandão Torres
Mestre
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23

Silva, Rafaéla Candido Oliveira da. "Validação de metodologia analítica por CLAE-DAD para determinação de compostos fenólicos e atividade biológica em coprodutos agroindustriais." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1771.

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CNPq; Fundação Araucária
A região Sul do Brasil, em especial, os estados do Paraná e Santa Catarina destacam-se pelo cultivo de uvas e maçãs para consumo in natura e, visando agregar valor a estes produtos, processam o material para a elaboração de vinhos, sucos e geleias. Como resultado grandes quantidades de coprodutos, como cascas, sementes e bagaço, são produzidos tornando-se problemas ambientais. Estudos de reaproveitamento desses coprodutos têm despertado interesse, pois têm demonstrado um elevado potencial biológico, em virtude da presença de altos teores de compostos fenólicos, que são associados a uma menor incidência de doenças ocasionadas pelo estresse oxidativo, devido as suas propriedades antioxidantes, anti-inflamatórias e antibacterianas. Atualmente, poucos estudos são apresentados sobre a composição fenólica e potencial biológico dos resíduos de uvas da variedade Bordô (Vitis labrusca) e maçã (Malus domestica) variedade Gala, cultivadas na região Sul do Brasil. Dentro deste contexto, os objetivos desse estudo foram: comparar a eficiência da extração sólido-líquido e líquido-líquido, realizar a otimização e validação de metodologia analítica por CLAE-DAD para a separação, identificação e quantificação de compostos fenólicos multiclasses, avaliar a atividade antioxidante pelos métodos de sequestro dos radicais livres 2,2 difenil-1- picrilhidrazina (DPPH) e 2,2-azino-bis-(3-etil-benzotiazolina-6-ácido sulfônico) (ABTS), método de redução do Fe3+ a Fe2+ (FRAP), ORAC, CLAE-FR-ABTS on-line, Rancimat e determinação de compostos fenólicos totais de três coprodutos agroindustriais, bagaço e engaço de uva Bordô produzidos na região Sudoeste do Paraná e bagaço de maçã Gala oriundo do Oeste de Santa Catarina. A otimização e validação do método cromatográfico apresentaram parâmetros de qualidade satisfatórios para os compostos de interesse e a extração sólido-líquido foi o mais eficiente em extrair os fenólicos avaliados. Os três coprodutos avaliados apresentaram teores significativos de compostos fenólicos quando analisados por CLAE, principalmente os flavonoides catequina e epicatequina, além de apresentaram significativa capacidade antioxidante. O extrato do engaço de uva apresentou a maior capacidade de sequestro dos radicais DPPH e ABTS e redução do ferro, além de elevado teor de compostos fenólicos totais. O extrato do bagaço de maçã apresentou a melhor resposta para o método Rancimat, o que indica elevado potencial em proteger o óleo da oxidação lipídica, não apresentado diferença significativa quando comparado ao antioxidante sintético TBHQ. Os resultados obtidos neste estudo demonstraram que os coprodutos agroindustriais analisados, são ricos em compostos fenólicos de alta capacidade antioxidante e, portanto, devem ser melhor explorados pelas indústrias de alimentos e farmacêutica.
The southern region of Brazil, especially the states of Parana and Santa Catarina stand out for growing grapes and apples for fresh consumption and in order to add value to these products, process the material for the production of wine, juices and jellies . As a result large quantities of by-products, such as peels, seeds and pulp are produced becoming environmental problems. Studies reuse of these by-products have attracted interest because they have shown a high biological potential, due to the presence of high levels of phenolic compounds, which are associated with a lower incidence of disease caused by oxidative stress, due to its antioxidant, antiinflammatory and antibacterial properties. Currently, few studies are presented on the phenolic composition and biological potential of waste grape variety Bordô (Vitis labrusca) and apple (Malus domestica) Gala variety, cultivated in southern Brazil. Within this context, the objectives of this study were: compare the efficiency of solidliquid and liquid-liquid extraction, perform the optimization and validation of analytical methodology by HPLC-DAD for the separation, identification and quantification of multiclass phenolic compounds, evaluate the activity antioxidant by sequestering methods of free radical 2,2-diphenyl-1 picrilhidrazina (DPPH) and 2,2-azino-bis (3- ethyl-benzthiazoline-6-sulphonic acid) (ABTS) solution, reduction of Fe3+ in Fe2+ method (FRAP), ORAC, RP-HPLC-ABTS online, Rancimat and determination of total phenolics three agro-industrial byproducts, pomace and stems grape Bordô produced in Paraná Southwest region and Gala apple pomace coming from the Santa Catarina West. Optimization and validation of chromatographic method showed satisfactory quality parameters for the compounds of interest and the solidliquid extraction was more efficient in extracting phenolic evaluated. The three byproducts evaluated showed significant levels of phenolic compounds when analyzed by HPLC, especially flavonoids, catechin and epicatechin besides that showed significant antioxidant capacity. The grape stems extract had the highest sequestration capacity of DPPH and ABTS radical and reduced iron, and high content of phenolic compounds. The apple pomace extract showed the best response to the Rancimat method, which indicates a high potential to protect the oil from lipid oxidation, was no significant difference when compared to synthetic antioxidant TBHQ. The results of this study showed that the agro-industrial coproducts analyzed are rich in phenolic compounds of high antioxidant capacity and therefore must be better explored by the food and pharmaceutical industries.
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24

Silva, Mondragón Guido Leonardo. "Development of an eco-friendly composite based on geopolymer matrix produced with fired clay brick powder and reinforced with natural fibers." Master's thesis, Pontificia Universidad Católica del Perú, 2018. http://tesis.pucp.edu.pe/repositorio/handle/123456789/13564.

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Current construction industry is responsible for a large amount of greenhouse gas emissions due to the widespread use of building materials with high-embodied energy such as ordinary Portland cement-based materials and steel. Therefore, this thesis presents the development of a new eco-friendly building material based on a geopolymer matrix produced with Fired Clay Brick Powder (FCBP) and reinforced with natural fibers as a low CO2 alternative for the traditional building materials. With this purpose, a review of recent advances in the application of geopolymer composites and geopolymers reinforced with natural fibers in the construction industry were first presented. This review covers two major eco-friendly materials for construction: first, geopolymers obtained from industrial by-products and waste materials, such as fly ash, ground granulated blast furnace slag, construction and demolition wastes and main tailings; and second, natural fibers used as reinforcement for geopolymer composite materials. Literature review allowed the definition of morphology, size, and the molar ratio of SiO2/Al2O3 in the raw material, together with the alkaline solution/solid ratio, NaOH concentration, SiO2/M2O molar ratio in the total alkaline solution and the curing conditions as key parameters in the formulation of geopolymers. It has been also found that the type, pre-treatment, amount and length of the natural fibers play an important role in the reinforcement of geopolymer matrices. Once key parameters of geopolymer composites production were identified, an attempt for the formalization of a methodology to improve the compressive strength of FCBP-based geopolymers is presented. The tests allowed the definition of optimum conditions of the FCBP-based geopolymers formulation and curing conditions, which resulted in a cementitious matrix with high compression strengths of up to 37 MPa. Nevertheless, high-strength geopolymers evidenced a fragile behavior and low ductility similar to Portland cement-based materials. Therefore, the last part of the work was focused on the evaluation of natural cellulose fibers (jute and sisal) as reinforcement of FCBP-based geopolymers. The results indicated that jute and sisal fiber addition at the optimum content significantly improved the compressive, splitting tensile and flexural strength with respect to the unreinforced geopolymer matrix and lead to a shifting of the failure mode from a brittle to a more ductile failure in all mechanical tests.
Tesis
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25

Silva, Darciely Lindalva da. "Estudo da sorção de tensoativos orgânicos em argilas bentoníticas." Universidade Federal da Paraí­ba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/451.

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Currently there are increasing studies on bentonite clays are organically modified. Since the method involves the addition of surfactants (sufactantes) ionic or nonionic most studied in the synthesis of organoclays, so that the synthesis can be performed in two ways: by ion exchange (the chemical reaction of double exchange) and ion -dipole (organic molecules are adsorbed on the surface of clay). Thus, the present work aims to study the sorption / cation exchange of ionic and nonionic surfactants on the surface of bentonite clays making them organophilic. In the process of organophilization bentonite clays have used two industrialized Brasgel PA and the Bentongel that their concentrations were varied from 3.16 to 7.16% by weight of clay. Was used to organophilization one nonionic surfactant amine ethoxylate grade 5 TA 50, where its concentration pierced 40-60 g/100g. After organophilizated clays were filtered, dried in an oven for 48 hours and passed in ABNT No. 200, to be well characterized. The sorption isotherms were constructed using data from thermogravimetry (TG), and adjusted to the linear model and Freundlich. From the isotherms was possible to infer the mechanism involved in the sorption is adsorption and cooperative multilayer adsorption, and the type of clay, the type of surfactant and the viscosity of the medium, variables influenced sorption. According to the results, it was possible to infer that clays with higher sorption capacity were Bentongel and Brasgel concentration of 3.16% when the WB organophilizated the Bentogel concentration of 7.16% organophilizated when the MT 50 and the Brasgel concentration 3.16% when organophilizated with TA 50.
Atualmente são crescentes os estudos sobre as argilas bentoníticas que são modificadas organicamente. Sendo o método que envolve a adição de tensoativos (sufactantes) iônicos ou não iônicos o mais estudado na síntese de argilas organofílicas, desta forma a síntese pode ser realizada de duas formas: por troca de íons (reação química de dupla troca), e íon-dípolo (moléculas orgânicas são adsorvidas na superfície da argila). Desta forma, o presente trabalho tem como objetivo estudar a sorção/troca catiônica de tensoativos iônicos e não iônicos na superfície das argilas bentoníticas tornando-as organofílicas. No processo de organofilização foram utilizadas duas argilas bentoníticas industrializadas, a Bentongel e a Brasgel PA que tiveram suas concentrações variadas de 3,16-7,16% em peso da argila. Foi utilizado para organofilização um tensoativo não-iônico a amina etoxilada de grau 5 TA 50, onde sua concentração varou de 40-60 g/100g. Após organofilizadas as argilas foram filtradas, secas em estufa por 48h e passadas em peneira ABNT nº 200, para assim serem caracterizadas. As isotermas de sorção foram construídas através dos dados de termogravimetria (TG), e ajustadas ao modelo linear e de Freundlich. A partir das isotermas foi possível inferir que o mecanismo envolvido na sorção é a adsorção cooperativa e adsorção em multicamadas, sendo o tipo de argila, o tipo de tensoativo e a viscosidade do meio, variáveis influenciáveis na sorção. De acordo com os resultados foi possível inferir que as argilas com maiores capacidade de sorção foram a Bentongel e Brasgel de concentração 3,16% quando organofilizada com o WB, a Bentongel de concentração 7,16% quando organofilizada com o TA 50 e a Brasgel de concentração 3,16% quando organofilizada com o TA 50.
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26

De, Oliveira Tiago. "Absorption de produits pharmaceutiques par les organoclays : des matériaux polyvalents pour des applications environnementales." Thesis, Orléans, 2019. http://www.theses.fr/2019ORLE3001.

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L’adsorption sur un substrat représente un moyen simple, efficace et peu couteux pour remédier aux polluants inorganiques et organiques. Les minéraux argileux ont montré par le passé des propriétés d’adsorption exceptionnelles pour de nombreux composés organiques. La modification chimique de leur surface via l’intercalation de surfactant, pour la préparation d’organoclays, permet d’améliorer leurs capacités d’adsorption, en particulier vis-à-vis des composés organiques hydrophobes tels que les produits pharmaceutiques (PPs) qui sont de plus en plus fréquemment retrouvés dans les réseaux d’eaux usées ainsi que les eaux de surface de par leurs fortes consommations et excrétions par la population associées à une inefficacité des systèmes épuratoires conventionnels pour éliminer ces composés. Dans ces travaux, l’adsorption de PPs d’actions thérapeutiques différentes et aux propriétés physico-chimiques variées sur une smectite de référence et des organoclays préparés au moyen de différents surfactants (cationiques et nonioniques) a été étudiée avec une attention particulière sur la détermination des mécanismes d’interactions entre PPs et adsorbants selon diverses conditions expérimentales afin (i) d’évaluer la stabilité des matériaux pour une application en contexte épuratoire et (ii) appréhender le rôle des phases minérales dans le devenir des micropolluants organiques dans le milieu naturel. Les données expérimentales obtenues par un jeu de techniques complémentaire révèlent que les organoclays de manière générale et plus particulièrement ceux préparés avec des surfactants nonioniques semblent être les matériaux les plus polyvalents pour l’adsorption des PPs. Les résultats soulignent également l’importance du milieu hydrophobe généré par l’intercalation de surfactants qui offrent de nouveaux sites d’interaction pour l’adsorption des PPs. Ceci permet de statuer de l’efficacité et du caractère prometteur des organoclays quant à leurs capacités de remédiation des effluents en station d’épuration
Adsorption represents an easy, simple and low-cost way to remove both organic and inorganic pollutants in water. Clay minerals are well known for their outstanding adsorption properties for numerous products. The chemical modification of its surface through the intercalation of surfactants for the preparation of organoclays considerably improves the adsorption properties, in particular for hydrophobic organic compounds such as pharmaceutical products (PPs) which are more and more commonly found in sewage and surface water. In the present contribution, the adsorption PPs with different therapeutic actions and varied physicochemical properties onto clay mineral and organoclay derivatives prepared with different surfactants (cationic and nonionic) has been studied with a particular understanding of the interactional mechanisms of PP with the adsorbents in order to (i) evaluate the stability of materials for an application in purifying context and (ii) to apprehend the role of the mineral phases in the fate of organic micropollutants in the natural environment. The experimental data obtained by a set of complementary techniques reveal that organoclays prepared with nonionic surfactants show a versatility for numerous PPs while the hydrophobic environment generated by the grafting of surfactants with alkyl-chains particularly enhances the adsorption of the organic compounds. The study confirmed the efficiency and the promising remediation behavior of organoclays for wastewater treatment
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27

Smedman, Annika. "Milk Fat Intake and Conjugated Linoleic Acid (CLA) Supplementation : Dietary Markers and Associations to Clinical and Biochemical Characteristics." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4820.

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28

Vieira, Fernanda Seabra Vianna. "Determinação de compostos carbonilados e carboxilados em derivados de petróleo." Instituto de Química, 2011. http://repositorio.ufba.br/ri/handle/ri/20243.

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A nafta e o etanol são matérias-primas importantes da indústria petro e alcoolquímica respectivamente, tendo o eteno e o propeno como seus principais derivados da primeira geração. A eficiência desses processos produtivos pode ser comprometida por traços de compostos carbonílicos e carboxílicos voláteis neles contidos. Tal contaminação pode afetar, por exemplo, a qualidade de embalagens de alimentos, uma vez que tais derivados são compostos precursores para produção dos plásticos utilizados nessas embalagens. No presente trabalho foram desenvolvidos métodos simples para a determinação de compostos carbonílicos e carboxílicos em matrizes líquidas e gasosas derivadas do petróleo por cromatografia em fase gasosa com sistema de detecção por ionização em chama (CG/DIC), cromatografia líquida de alta eficiência (CLAE), cromatografia gasosa acoplada à espectrometria de massas (CG/EM) e CG/DIC acoplado a sistema analítico Dean Switch. Para a determinação dos ácidos acético, propanóico, butanóico e pentanóico em matrizes líquidas e gasosas, a cromatografia em fase gasosa com sistema de detecção por ionização em chama por injeção direta utilizando coluna cromatográfica capilar FFAP (for free fatty acids) foi a técnica mais adequada. O desvio padrão relativo (RSD) obtido foi de 5,6% a 6,5% para 2 g.g-1 em n-hexano, 2,1% a 5,8% para 10 g.g-1 em etanol e 4,2 a 7,7% para 10 g.g-1 em propeno. Os limites de detecção encontrados foram de 0,036 - 0,12 g.g-1 em hidrocarbonetos gasosos (eteno e propeno), 0,047 - 0,16 g.g-1 em matrizes puras de hidrocarbonetos líquidos (n-hexano) e 0,08 – 0,18g.g-1 em matriz alcoólica (etanol). Para a determinação do teor de ácidos carboxílicos em matrizes complexas como a nafta, a CLAE foi a técnica utilizada, precedida de extração líquido- Fernanda Seabra Vianna Vieira 11/238 líquido sob condições controladas. O RSD obtido foi de 5,5% a 7,7% para 40 g.g-1 e o limite de detecção médio foi de 4 g.g-1. Para a determinação dos teores dos compostos carbonílicos (aldeídos e cetonas) em matrizes líquidas e gasosas, a cromatografia empregando o sistema analítico comercial Dean Switch mostrou-se como a mais adequada. Valores de RSD da ordem de 2,6% a 3,5% para propeno; 0,9% a 1,4% para n-hexano e 1,6% a 2,6% para a nafta em padrões contendo respectivamente 2 g.g-1, 2 g.g-1 e 10 g.g-1. Os limites de detecção de 0,033 - 0,084 g.g-1 (propeno), 0,021- 0,09 g.g-1 (n-hexano) e 0,049 - 0,26 g.g-1 (nafta) confirmam a eficiência de detecção e quantificação para matrizes de hidrocarbonetos de origem petroquímica tipicamente inferiores a 10 g.g-1. A partir dos resultados obtidos foi feita uma avaliação comparativa entre as técnicas, evidenciando as vantagens e desvantagens de cada método para cada aplicação específica.
Although metals and nitrogen & sulfur compounds have been the main concern in the petroleum industry, issues on the harmful effects on catalysts poisoning and products contamination of other contaminants such as oxygen- containing compounds have been raised. Trace amounts of carbonyl and carboxyl compounds in petroleum products can lead to catalyst poisoning and overall decrease on reactions yield. Furthermore, oxygenates may be present in the polyethylene and polypropylene resins, affecting the quality of the food packagings obtained from these materials. The available literature on C1-C5 aldehydes, ketones and carboxylic acids determination in petroleum products such as naphtha, ethylene and propylene is quite rare. Therefore, in the present work we intend to review the analytical approaches that could be applied to such analytical purpose, present the features of each potential technique and some studies performed on somewhat similar matrices. For acetic, propanoic, butanoic and pentanoic acids determination in liquid and gas matrices, gas chromatography with flame ionization detector and FFAP for free fatty acids capillary column was the most appropriate method. The relative standard deviation (RSD) was 5.6% to 6.5% in the range of 2 g.g-1 in n-hexane, 2.1% to 5.8% in the range of 10 g.g-1 in ethanol and 4.2 to 7.7% in the range of 10 g.g-1 in propylene. The detection limits found were from 0.036 to 0.12 g.g-1 in hydrocarbons gases (ethylene and propylene), 0.047 to 0.16 g.g-1 in pure liquid hydrocarbons (n-hexane) and 0.08 to 0.18 g.g-1 in alcoholic matrices (ethanol). For carboxylic acid determination in complex matrices such as naphtha, the HPLC technique was used, preceded by liquid-liquid extraction under Fernanda Seabra Vianna Vieira 9/238 controlled conditions. The RSD obtained was 5.5% to 7.7% in the range of 40 g.g-1 within the average detection limit was 4 g.g-1. For carbonyl compounds (aldehydes and ketones) determination in gas and liquid matrices, the commercial analytical system Dean Switch proved to be the most appropriate. RSD values of around 2.6% to 3.5% for propylene; 0.9% to 1.4% for n-hexane and 1.6% to 2.6% for naphta in standards containing respectively 2 g.g-1, 2 g.g-1 and 10 g.g-1. The detection limit of 0.033 to 0.084 g.g-1 (propylene), 0.021 to 0.09 g.g-1 (n-hexane) and 0.049 to 0.26 g.g-1 (naphtha) confirm the efficiency of detection and quantification for range of hydrocarbons of petrochemical origin typically less than 10 g.g-1.
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CARDOSO, Fabiana Fernandes de Santana e. Silva. "Desenvolvimento e validação de uma metodologia analítica, em CLAE-PDA, para avaliação da estabilidade do 4-nerolidilcatecol na presença de seus produtos de degradação." Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tde/2135.

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The 4-nerolidylcatechol is the main secondary metabolite of the species Pothomorphe umbellata L. Miq. with established antioxidant, anti-inflammatory and photoprotective actions. Nevertheless, after its isolation and storage, evidence of photoinstability is observed, in a way that the characterization of the factors that influence such instability become mandatory, facing the perspective of a new drug development. Therefore, the aim of this paper was to develop and validate a hromatographic methodology able to analyze the degradation kinetic of the 4-NRC, in the presence of the degradation products, using the high performance liquid chromatography coupled to a detector with photodiodes (HPLC-PDA). Our results showed that the analytical method was selective (5 μg/mL) and linear over a wide range of concentrations (5.0 to 500.0 μg/mL) indicating high intra-day (0,02 2.83%) and inter-day precision (0.59 4.89%), besides accuracy (98.46 104.88%) and ruggedness. The photolytic study showed a fast degradation of 4- nerolidylcatechol (tR = 25 min), generating a major product after a total run time of 8 min. The hydrolytic study showed high instability of the substance in alkaline medium (pH 13.00), generating a major product after a chromatographic run time of 26 min. In acid conditions (pH 1.00), the degradation of 4-NRC was slow and partial, even though after 72 hours of exposure, and under heating stress. The main product of the acid degradation was seen after 12 min. The degradation kinetics of 4-NRC in alkaline and photolytic conditions showed evidences of a 2º order profile, for both reactions. Accordingly, it may be proposed the storage of 4-NRC in neutral medium, under refrigerated conditions and also, protected from light incidence preventing degradation. In addition, it must be avoided storage in solution, mainly in alkaline conditions, once they accelerate the rate of 4-NRC degradation.
O 4-nerolidilcatecol (4-NRC) é o principal metabólito secundário da espécie Pothomorphe umbellata L. Miq. com comprovadas ações antioxidante, antiinflamatória e fotoprotetora. No entanto, após isolamento e armazenamento deste observam-se evidências de fotoinstabilidade de modo que, a caracterização dos fatores que influenciam tal instabilidade torna-se imperativa mediante a perspectiva do desenvolvimento de um novo fármaco. Assim, o objetivo deste trabalho foi desenvolver e validar um método cromatográfico capaz de analisar a cinética de degradação do 4-NRC, na presença dos produtos gerados, empregando-se a cromatografia líquida de alta eficiência acoplada a detector com arranjos de fotodiodos (CLAE-PDA). Os resultados obtidos demonstraram que as condições cromatográficas desenvolvidas utilizando gradiente de eluição contendo MeOH:ACN:H2O como fase móvel possibilitou adequada sensibilidade (5 μg/mL), linearidade (5-500 μg/mL), precisão intra (0,02 2,83%) e inter-dias (0,59 4,89%), além de exatidão (98,46 - 104,88%) e robustez. O estudo fotolítico demonstrou rápida degradação do 4-NRC (tR = 26 min), com formação de um produto majoritário (tR = 8 min). Dados do estudo hidrolítico evidenciaram elevada instabilidade do 4-NRC em meio alcalino (pH 13,00), observando-se um produto majoritário com tR próximo a 26 min. Na condição ácida (pH 1,00), a degradação do 4-NRC foi lenta e parcial, mesmo após 72 horas de exposição, sob aquecimento. O principal produto de degradação ácida apresentou tR próximo a 12 min. A cinética de degradação do 4-NRC, em meio ácido e sob condição fotolítica, analisada segundo o método gráfico do decaimento da concentração do 4-NRC, aponta que ambas reações apresentam perfil sugestivo de 2ª ordem. Neste contexto, sugere-se o armazenamento da substância em pH neutro, sob condições refrigeradas e protegidas da incidência da luz de modo a prevenir a degradação. Deve-se evitar ainda, o armazenamento em soluções, principalmente alcalinas, pois a velocidade de degradação torna-se acelerada.
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Azócar, Nordeman Patrik-Patricio. "Design of a modular solar powered outdoor lighting system." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61253.

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This reports describes a master thesis project in Industrial Design Engineering at Lulea University of Technology in collaboration with Clas Ohlson.The master thesis was performed during 2015/2016 and is part of a product development project at Clas Ohlson aiming to develop a new kind of solar powered out door light. Clas Ohlson have limited experience with in house product development, and this project could be a pilot project to evaluate future in house product development.This projects main focus is the creative parts of the product development process and the detail development.The product developed resulted in a product with high customisation potential in many aspects including aesthetic, mounting, electronic and packaging.The resulting material, such as CAD-files, is handed over to Clas Ohlson for them to adjust if necessary in order to take the result in to production. The starting point is the company ́s desire to comply with one of their main objectives: provide sustainable products.The desire was for me to develop a solar powered outdoor light.The result is a module based system which can be expanded in multiple ways, from changing the function, to changing the appearance. In the chapter results you also find a suggested launch plan showing the width of the presented solution and the many opportunities the end user would have to upgrade their product without generating excessive waste.
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Rezende, Ricardo Leite de Oliveira. "Separação dos enatiômeros do cetoprofeno e do fenoprofeno por CLAE em fase estacionária quiral." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9139/tde-04022009-195023/.

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Durante muito tempo, os fármacos quirais de origem sintética foram comercializados predominantemente como racematos. Atualmente, sabe-se que os enantiômeros de um fármaco quiral podem apresentar propriedades farmacocinéticas, farmacodinâmicas e toxicológicas bastante distintas. Assim sendo, técnicas analíticas enantiosseletivas são fundamentais para a pesquisa e para o controle da qualidade desses fármacos. O cetoprofeno e o fenoprofeno são dois fármacos quirais, pertencentes à classe dos agentes antiinflamatórios não-esteróides derivados do ácido propiônico. Seus enantiômeros apresentam significativas diferenças farmacodinâmicas. Por essa razão, pretendeu-se desenvolver, no presente trabalho, métodos de separação enantiomérica para ambos os fármacos. Para tanto, utilizou-se a técnica de cromatografia a líquido de alta eficiência em fase estacionária quiral (coluna Whelk-O 1), nos modos normal e reverso. Abordagens uni- e multivariadas foram utilizadas para desenvolver e otimizar os métodos de separação. Pôde-se observar que a enantiosseletividade exibida pela coluna Whelk-O 1 em fase normal é superior àquela exibida em fase reversa. Empregando a CLAE em fase normal, foi possível desenvolver métodos de separação apropriados para os enantiômeros de ambos os fármacos. Em fase reversa, no entanto, apenas os enantiômeros do fenoprofeno puderam ser separados satisfatoriamente.
For a long time, the synthetic chiral drugs were marketed mainly as racemates. Currently, it is known that enantiomers of chiral drugs may exhibit quite different pharmacokinetic, pharmacodynamic and toxicological properties. Therefore, enantioselective analytical techniques are critical to the research and quality control of these drugs. Ketoprofen and fenoprofen are two chiral drugs, belonging to the class of propionic acid-derived nonsteroidal anti-inflammatory agents. Their enantiomers show significant pharmacodynamic differences. For that reason, we aimed to develop, in this work, separation methods for the enantiomers of both drugs. In order to do so, it was used the high-performance liquid chromatography technique and the Whelk-O 1 column as the chiral stationary phase, under normal- and reversed-phase modes. Uni- and multivariate approaches were used to develop and optimize the separation methods. It was noted that the enantioselectivity exhibited by the Whelk-O 1 column under normal-phase mode is higher than that exhibited under reversed-phase mode. Under normal-phase mode, it was possible to achieve an appropriate separation for the enantiomers of both drugs. Under reversed-phase mode, however, only the enantiomers of fenoprofen could be successfully separated.
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Oliveira, Leilanne MÃrcia Nogueira. "QuantificaÃÃo de rutina, atividade antioxidante e antimicrobiana de extratos de polpas e subprodutos de frutas tropicais." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13080.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Nos Ãltimos anos o consumo de frutas tropicais tem aumentado, principalmente, devido aos seus benefÃcios para a saÃde, entre eles à baixa incidÃncia de doenÃas degenerativas. Esses benefÃcios sÃo atribuÃdos, em sua maioria, aos constituintes antioxidantes, como os compostos fenÃlicos e vitaminas. A rutina à um composto fenÃlico que possui vÃrias atividades biolÃgicas, tais como agentes antitumorais e propriedades antibacterianas. Com isso, o presente estudo objetivou avaliar a atividade antimicrobiana e antioxidante de extrato de rutina obtido de polpas e subprodutos de frutos tropicais encapsulado em matriz de goma do cajueiro. As frutas utilizadas foram: acerola, goiaba, manga e cajÃ-umbu. Elas foram despolpadas e caracterizadas fÃsico- e quimicamente. A polpa e o subproduto de acerola apresentaram maior atividade antioxidante total com 91,33 e 51,62 ÂM de Trolox. g-1, respectivamente. Sendo que os subprodutos de manga, goiaba e cajÃ-umbu obtiveram atividade antioxidante superior as suas respectivas polpas. A presenÃa de rutina foi observada em todas as polpas e subprodutos, sendo o subproduto de cajÃ-umbu o que obteve maior teor com 1852,40 Âg.g-1, seguido da polpa de acerola com 184,66 Âg.g-1. Esses extratos com maiores teores de rutina e rutina padrÃo (Sigma-Aldrich) foram encapsulados com goma do cajueiro. As nanopartÃculas formadas foram caracterizadas fisicamente e apresentaram tamanhos mÃdios variando de 174,20 nm a 907,60 nm. Ao avaliar o potencial antibacteriano, observou-se que a rutina e sua respectiva nanopartÃcula nÃo possuem essa propriedade contra as bactÃrias Eschechia coli, Salmonella Enteritidis, Staphylococcus aureus e Listeria monocytogenes na concentraÃÃo de atà 10 mg/mL. Os extratos de polpa de acerola (EPA) e subproduto de cajÃ-umbu (ESC) apresentaram atividade antibacteriana, sendo mais eficientes contra bactÃrias Gram-positivas. Os extratos nÃo encapsulados com goma do cajueiro foram mais efetivos do que os encapsulados.
In recent years the consumption of tropical fruits has increased, mainly due to its health benefits, including the low incidence of degenerative diseases. These benefits are awarded, mostly to the antioxidant constituents, such as phenolic compounds and vitamins. Rutin is a phenolic compound which possesses various biological activities such as antibacterial and antitumor agents. Thus, the present study aimed to evaluate the antimicrobial and antioxidant activities of extract rutin obtained from pulps and by-products of tropical fruits encapsulated array of cashew gum. The fruits used were: acerola, guava, mango and caja-umbu. They were pulped and characterized physico-chemically. The pulp and the by-product of acerola had higher total antioxidant activity with 91.33 and 51.62 mM Trolox. g-1, respectively. Since the by-products of mango, guava and caja-umbu had higher antioxidant activity their respective pulps. The presence of rutin was observed in all pulps and byproducts, and the byproduct of caja-umbu that obtained with higher content 1852.40 μg.g-1, followed of the pulp with 184.66 μg.g-1. These extracts with higher concentrations of rutin and standard rutin (Sigma-Aldrich) were encapsulated with cashew gum. The formed nanoparticles were characterized physically and showed average sizes ranging from 174.20 nm to 907.60 nm. In evaluating the antimicrobial activity, it was found that rutin and its respective nanoparticle do not have this property against bacteria Eschechia coli, Salmonella Enteritidis, Staphylococcus aureus and Listeria monocytogenes at a concentration of up to 10 mg / ml. The extracts of acerola pulp (EPA) and byproduct caja-umbu (ESC) showed antibacterial activity, being more effective against Gram-positive bacteria. Extracts not encapsulated with cashew gum were more effective than encapsulated.
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Courtois, Noémie. "Etude du vieillissement de boues de papeterie utilisées pour la fabrication de briques de terre cuite : influence des produits de dégradation sur les caractéristiques céramiques des matériaux." Thesis, Bourgogne Franche-Comté, 2021. http://www.theses.fr/2021UBFCD003.

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Des boues de papier peuvent être incorporées au sein des mélanges industriels argileux pour l'élaboration de briques en terre cuite. Cette incorporation a plusieurs objectifs et avantages, notamment au niveau de l'optimisation du séchage des briques via l’effet hydrophile des fibres de papier, ainsi que pour la création de porosité au sein des briques améliorant leur résistance thermique. Or, certains phénomènes néfastes peuvent apparaître à l’échelle industrielle : fissuration des briques et apparition d'efflorescences (blanchiment de la surface des briques), notamment lorsque les boues de papier présentent un certain vieillissement. Cette thèse a pour but d'étudier et d'identifier les substances provoquant ces phénomènes et de définir les conditions dans lesquelles leur apparition est favorisée. Nous étudierons pour cela le vieillissement de boues de papier ainsi que leur incorporation à des mélanges argileux. L'influence de la nature et de l’état des boues de papier sur le comportement des produits finis sera ainsi étudiée via le façonnage et la caractérisation (paramètres physico-chimiques et céramiques) de mélanges recomposés argiles et boues de papier. Les AGV identifiés lors du vieillissement ont une influence, dépendant de la matière fibreuse (longueur des fibres, ratio cellulose/lignine), sur les caractéristiques céramiques des matériaux (diffusivité et séchage). Ces modifications peuvent conduire à l’apparition des défauts lorsqu’un seuil de 10 mg d’AGV/g de boues de papier, incorporées à 12% dans la phase argileuse, est dépassé. Enfin, une réflexion est menée sur les conditions optimales de stockage et d'utilisation permettant de réduire ou de contrôler l'apparition des phénomènes indésirables
Paper sludge can be incorporated in industrial clayey mixtures used in fired-clay bricks formulation. This incorporation has several aims and benefits, especially for drying optimization of the products, due to hydrophilic effect of paper fibers, and creating porosity which improves the fired brick thermal insulation. However, some drawbacks may occur such as brick cracking or efflorescence (bleaching of brick surfaces), in particular when the added paper sludge presents a significant ageing. The purpose of this thesis consists in identifying the parameters responsible for cracks and efflorescence on the bricks and defining the conditions preventing the defects occurrence. Therefore, the ageing of paper sludges as well as their incorporation into clayey mixtures were studied. Several paper sludges of different compositions and degradation states were tested, and their impacts on the formulated bricks characteristics (physico-chemical and ceramic parameters) were investigated. Volatile Fatty Acids produced during paper sludge ageing were identified as key parameters to explain defect formations on the bricks, with a threshold value of 10 mg VFA/g of paper sludge, incorporated at 12% in the clay phase. Depending on the fibrous paper sludge characteristics (fiber length, cellulose/lignin ratio), VFAs have an influence on the water diffusivity and drying of the bricks. Finally, suggestions are made for the optimization of storage conditions of paper sludges before utilization and brick/paper sludge formulation. This would result in significant reduction of production defects
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Baba, El Mokhtari Yasmina. "Preferencias de los consumidores hacia el Omega 3 como reclamo de salud en los productos alimentarios." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/458449.

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In this thesis we analyzed the preferences of consumers towards foods enriched with healthy components, in particular omega-3 (n-3). Beef and egg have been chosen as case studies. In the first case study, the preferences in three Spanish cities (Barcelona, Zaragoza and Pamplona) were analyzed in order to estimate the relative importance of beef attributes, including their enrichment with omega-3 unsaturated fatty acids and the Conjugated linoleic acid (CLA). Furthermore, we evaluated the impact of sensory experience on consumer preferences differentiated by the information received. Data were collected from a structured and self-completed questionnaire in a controlled environment, by tasting 4 different meat samples in the three cities (647 total consumers). The choice experiment was applied and the Generalized Multinomial Model model (G-MNL) was applied before and after the consumers evaluated the acceptability of meat samples. In the second case study, the potential appropriateness of the Analytical Hierarchy Process (AHP) technique to analyze consumers¿ acceptance of three types of eggs (conventional, n-3 enriched and free-range) was assessed and compared with the traditional 9-point hedonic scale. The relative importance of the main attributes of eggs¿ purchase including its enrichment with polyunsaturated fatty acids (omega-3) was also analyzed. Data were obtained from a face-to-face questionnaire completed by consumers (n=122) in a controlled environment. Analyzing the preferences of enriched meat with n-3, results showed a significant impact of sensory evaluation on consumers¿ preferences. This impact is differentiated by the information received. The utility of meat enriched with n-3 in the three cities increased significantly after tasting the meat, especially for consumers without information, while the utility of meat enriched with CLA was not significant. The results showed an increase in the overall acceptability of meat enriched with n-3 and CLA compared to conventional meat and the information offered to consumers had no significant impact on their scores. Analyzing the preferences of enriched eggs with n-3, results showed agreement between the AHP technique and the 9-point scale showing that n-3 enriched eggs had lower flavor acceptance. The most important attributes that determine preferences for egg purchase were the type and the egg price followed by the origin and the egg size. The AHP approach seems to be a reliable tool to evaluate consumer hedonic preferences. However, further testing on other food products with larger sample sizes is needed. The results confirm the marketing opportunities related to the benefit of the application of health component with health properties mainly the enrichment with polyunsaturated fatty acids adaptable to beef and eggs, in particular the n-3, are promising is they are well introduced in the animal feed. The food industry is encouraged to benefit from these factors as a strategy of product differentiation and market segmentation.
En esta tesis hemos analizado las preferencias de los consumidores hacia los alimentos enriquecidos con componentes saludables en particular el omega-3 (n-3). La carne de vacuno y el huevo han sido elegidos como casos de estudio. En el primer caso de estudio se han analizado las preferencias en tres ciudades españolas (Barcelona, Zaragoza y Pamplona) con el objetivo de estimar la importancia relativa de atributos de la carne de vacuno incluyendo su enriquecimiento con ácidos grasos insaturados omega-3 y el ácido linoleico conjugado (CLA). Asimismo, hemos evaluado el impacto de la experiencia sensorial sobre las preferencias de los consumidores diferenciados por la información recibida. Los datos fueron recogidos de un cuestionario estructurado y auto-completado, en un ambiente controlado, probando 4 muestras de carne diferentes en las tres ciudades (647 consumidores totales). El experimento de elección analizado con el modelo Multinomial Generalizado (G-MNL) fue aplicado antes y después de que los consumidores evaluaran la aceptabilidad de la carne enriquecida. En el segundo caso de estudio, se ha evaluado la idoneidad de la técnica del Proceso de la Jerarquía Analítica (AHP) para analizar la aceptación por los consumidores de tres tipos de huevos (convencional, enriquecido con n-3 y campero) y comparar los resultados con la escala hedónica tradicional de 9-puntos. También se ha analizado la importancia relativa de los principales atributos de la compra de huevos, incluyendo su enriquecimiento con ácidos grasos poliinsaturados (omega-3). Los datos se obtuvieron de un cuestionario cara a cara completado por los consumidores (n = 122) en un ambiente controlado. Analizando las preferencias de la carne enriquecida con n-3, los resultados mostraron un impacto significativo de la evaluación sensorial sobre las preferencias. Este impacto se diferencia por la información recibida. La utilidad de la carne enriquecida con n-3 en las tres ciudades se incrementó significativamente después de probar la carne, sobre todo para los consumidores sin información, mientras que la utilidad de la carne enriquecida con CLA no fue significativa. Los resultados mostraron un aumento de la aceptabilidad global de la carne enriquecida con n-3 y CLA respecto a la carne convencional y la información ofrecida a los consumidores no tuvo impacto significativo en sus puntuaciones. Analizando las preferencias de los huevos enriquecidos con n-3, los resultados mostraron una relativa concordancia entre la técnica de AHP y la escala hedónica de 9 puntos mostrando que los huevos enriquecidos con n-3 tenían una aceptación de sabor más baja. Los atributos más importantes que determinan las preferencias para la compra de huevos fueron el tipo y el precio del huevo seguido por el origen y el tamaño del huevo. El enfoque AHP parece ser una herramienta potencialmente adecuada para evaluar las preferencias hedónicas del consumidor. Sin embargo, más pruebas en otros productos alimenticios y grandes tamaños maestrales son necesarios. Los resultados confirman las oportunidades de marketing relacionadas con el beneficio de la aplicación de moléculas con propiedades saludables principalmente el enriquecimiento con ácidos grasos poliinsaturados adaptables a la carne de vacuno y los huevos son prometedoras si son correctamente introducidos en el pienso. La industria alimentaria está llamada a beneficiarse de estos factores como una estrategia de diferenciación de producto y de segmentación de mercado.
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35

Braga, Renata Martins. "Uso de argilominerais e diatomita como adsorvente de fen?is em ?guas produzidas na ind?stria de petr?leo." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12884.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The oil production in Brazil has been increasing each year. Consequently, increasing volumes of water produced are generated with large quantities of contaminants, which brings many problems in disposing of these waters. The concern that the concentrations of contaminants in water produced meet existing laws for disposal of effluents, has been extremely important for the development of different techniques for treatment of water produced. The study of clay minerals as adsorbents of organic contaminants has grown considerably so in order to combine the low cost with the efficiency of environmental preservation and health issues. Thus, this study aims to understand the characteristics of vermiculite clay, sodium bentonite, calcium bentonite and diatomite and evaluate their performance as adsorbents for phenol in the water produced. Through adsorption isotherms it was possible to observe the behavior of these adsorptive clay and diatomite for adsorption of phenol, the main phenolic compound found in water produced. Different concentrations of synthetic solutions of phenol were put in touch with these adsorbents under same conditions of agitation and temperature. The adsorbents were composted adsorptive favorable, but the vermiculite and diatomite showed little capacity for absorption, being suggested for absorbs small concentrations of phenol in the balance isothermal
A produ??o de petr?leo no Brasil vem aumentando a cada ano. Em conseq??ncia, volumes crescentes de ?gua de produ??o s?o gerados com grandes quantidades de contaminantes, o que traz v?rios problemas no descarte dessas ?guas. A preocupa??o para que as concentra??es dos contaminantes da ?gua produzida atendam as legisla??es vigentes para descarte de efluentes, tem sido extremamente importante para o desenvolvimento de diferentes t?cnicas de tratamentos da ?gua produzida. O estudo de argilominerais como adsorventes de contaminantes org?nicos tem crescido de forma consider?vel, a fim de se aliar o baixo custo com a efici?ncia da preserva??o ambiental e sa?de publica. Assim, este trabalho tem como objetivo conhecer as caracter?sticas dos argilominerais vermiculita, bentonita s?dica, bentonita c?lcica e da diatomita e avaliar seus desempenhos como adsorventes de fen?is na ?gua produzida. Atrav?s das isotermas de adsor??o p?de-se abservar os comportamentos adsortivos desses argilominerais e da diatomita para adsor??o do fenol, principal composto fen?lico encontrado na ?gua produzida. Diferentes concentra??es de solu??es sint?ticas de fenol foram postas em contato com estes adsorventes sob agita??o e mesmas condi??es de temperatura. Os adsorventes apresentaram comportamento adsortivo favor?vel, por?m a vermiculita e diatomita apresentaram pequena capacidade de adsor??o, sendo sugeridas para adsorver pequenas concentra??es de fenol no equil?brio isot?rmico
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36

Conegundes, Jéssica Leiras Mota. "Caracterização química, estudo farmacológico e toxicológico de Siparuna guianensis Aublet. (Siparunaceae)." Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/7887.

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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A espécie Siparuna guianensis Aublet. (Siparunaceae), conhecida como negramina, capitu, folha santa e limão-bravo, é amplamente distribuída no território nacional. A espécie tem sido tradicionalmente utilizada no combate de sintomas de algumas patologias como febre, inflamação, dores de cabeça e no corpo. O presente estudo teve como objetivos avaliar a atividade antioxidante, antinociceptiva, anti-inflamatória e toxidez oral aguda da partição em diclorometano (PDCM) das folhas de S. guianensis, bem como determinar o perfil químico de PDCM e suas frações. Para tal, as folhas secas foram submetidas à extração em metanol por maceração estática. O extrato metanólico foi então particionado, primeiramente com hexano, seguido de diclorometano, obtendose a PDCM que, por sua vez, foi fracionada e forneceu 14 frações (FD1 a FD14). O perfil químico da PDCM e suas frações foi determinado por cromatografia em camada delgada (CCD) e cromatografia líquida de alta eficiência (CLAE), possibilitando a identificação de constituintes terpênicos e flavonoides. Com relação à atividade antioxidante in vitro, a PDCM foi eficaz em reduzir o radical DPPH (CI50 25 μg/mL); no método do fosfomolibidênio foi encontrado o valor de 0,34 mg/mg de PDCM em equivalentes de ácido ascórbico; no método do TBA a amostra na concentração de 7,5 mg foi capaz de inibir a peroxidação lipídica de forma estatisticamente igual à substância de referência (BHT), na mesma concentração. In vivo, a atividade anti-inflamatória foi avaliada em camundongos pelo método do edema de orelha induzido pelo óleo de cróton e pelo modelo de peritonite induzida por LPS. No primeiro modelo PDCM administrada por via oral (v.o.) foi capaz de reduzir significativamente o edema nas doses de 100 e 300 mg/kg em 54 e 52%, respectivamente. Enquanto que no segundo ensaio, PDCM na dose de 100 mg/kg foi capaz de inibir a migração leucocitária em 53%. O estudo toxicológico agudo, durante 14 dias, mostrou que esta amostra é segura para administração por via oral. PDCM v.o. apresentou ação antinociceptiva em dois dos três modelos utilizados. No modelo de contorções abdominais induzidas por ácido acético, as doses de 100, 200 e 300mg/kg foram capazes de inibir o número de contorções em 67, 71 e 83%, respectivamente. No teste da formalina, foi observada atividade tanto na nocicepção neurogênica, quanto na nocicepção inflamatória. Na primeira, todas as doses (100, 200 e 300 mg/kg) foram eficazes reduzindo em 56, 54 e 48%, respectivamente, o tempo de lambida. Do mesmo modo, na segunda fase todas as doses foram eficazes, porém de forma menos significativa que na primeira fase, reduzindo o tempo de lambida em 29, 38 e 44%, respectivamente. Devido à natureza comportamental dos ensaios antinociceptivos, o teste do campo aberto mostrou que a amostra não tem atividade sobre a locomoção dos animais. Os resultados indicam que a PDCM de S. guianensis possui potencial antioxidante, antinociceptiva e anti-inflamatória, provavelmente relacionados aos constituintes terpênicos e flavonoides presentes na espécie.
The species Siparuna guianensis Aublet. (Siparunaceae), known as negramina, capitú, folha-santa e limão-bravo, is widely distributed around the national territory. Species have traditionally been used to combat the symptoms of some pathologies fever, inflammation, headaches and body aches, and other disorders. The present study aimed to evaluate the antioxidant, antinociceptive and anti-inflammatory activities and acute oral toxicity profile of the dichloromethane partition (PDCM), as well as to determine the chemical profile of PDCM and its fractions. For this, the dry leaves were subjected to methanol extraction by static maceration. The methanolic extract was subject to liquidliquid partition, firstly with hexane, followed by dichloromethane, to obtain the dichloromethane partition (PDCM). Then, PDCM was fractionated, and 14 fractions (FD1 – FD14) were collected. The PDCM and fractions chemical profiles was performed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC), which allowed the identification of terpenes and flavonoids. According to the in vitro tests, PDCM was effective in reducing the DPPH radical (IC50 25 μg/mL); the value of 0.34 mg/mg of PDCM in ascorbic acid equivalents was determined using the fosfomolybdenium assay; the sample at 7.5 mg was able to inhibit lipid peroxidation with no statistical difference compared to the reference substance (BHT) at the same concentration in the TBA assay. Besides, the in vivo anti-inflammatory activity was investigated in mice by the cróton oil-induced ear edema and by the model of peritonitis induced by LPS. PDCM was capable to reduce the ear edema at 100 and 300 mg/kg by 54% and 52%, respectively. Also, PDCM inhibited the leucocyte migration by 53% at 100 mg/kg. The acute toxicological evaluation, during 14 days, suggested that the oral administration of this sample is safe. PDCM also showed antinociceptive action in two of the three models used. The number of writhing was reduced by 67%, 71% and 83% at 100, 200 and 300 mg/kg, respectively, in acetic acid-induced writhing test. The neurogenic and inflammatory antinociceptive activity was also observed by the formalin test. All doses (100, 200 and 300 mg/kg) were effective, reducing by 56%, 54% e 48% the licking time during the neurogenic inflammation, respectively. All doses (100, 200 and 300 mg/kg) were also effective in the second phase, however in a less significant manner, reducing the licking time by 29%, 38%, and 44%, respectively. Due to the behavioral nature of the antinociceptive assays, the open field test was carried out to ensure that the sample has no interference on animal locomotion. The results indicated that PDCM from S. guianensis is endowed with antioxidant, antinociceptive and antiinflammatory potential, probably related to the terpenes and flavonoids presented in this species.
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37

Dantas, Suylan Lourdes de Araújo. "Influência da rota alcoólica no processo de organofilização de argilas bentoniticas para uso em fluidos de perfuração não aquosos." Universidade Federal da Paraí­ba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/452.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Bentonite clays may be defined as a clay consisting predominantly of the smectite group clay minerals, particularly montmorillonite. There is naturally organophilic bentonite clays, these can be modified by specific treatments with surfactants (ionic or nonionic), passing to its hydrophobic nature hidofílica. Organophilic clays are widely used in drilling fluids non-aqueous, these fluids are mixtures of different components used in a well bore. One of the basic characteristics of drilling fluids is to minimize physical and chemical changes of the formations to be drilled. Recent studies have demonstrated the influence of clay, and presence of a dispersant surfactant rheology of the fluids. In this study we verified the influence of clay and surfactant in the production of organoclays using a route alcoholic and was therefore analyzed the rheology of non-aqueous fluids. Therefore, we performed the characterization of samples of clays; through thermogravimetric analysis, X-ray Diffraction, Differential Thermal Analysis and Particle Size Analysis for the organoclays were characterized by XRD and X-ray fluorescence were eventually produced in non-aqueous fluids according to Petrobras to perform normalization of rheological tests. The results indicated that the influence of the ratio clay / surfactant and the route alcoholic on the rheology of non-aqueous drilling fluids.
Argilas bentoníticas podem ser definidas como sendo uma argila constituída essencialmente de argilominerais do grupo das esmectitas, especialmente a montmorilonita. Não sendo as argilas bentoníticas naturalmente organofílicas, estas podem ser modificadas através de tratamentos específicos com tensoativos(iônicos ou não-iônicos), passando sua natureza de hidofílica para hidrofóbica. As argilas organofilicas são amplamente utilizadas em fluidos de perfuração não-aquosos, estes fluidos são misturas de diferentes componentes utilizados em uma perfuração de poço. Uma das características básicas dos fluidos de perfuração é minimizar alterações físicas e químicas das formações a serem perfuradas. Estudos recentes demonstraram a influência do tipo de argila, tensoativo e presença de defloculante na reologia dos fluidos. Neste trabalho verificamos a influência do teor de argila e tensoativo na produção de argilas organofilicas, utilizando uma rota alcoólica e conseqüentemente foi analisado a reologia dos fluidos não aquoso. Para tanto, realizamos a caracterização das amostras de argilas; através de Análise Termogravimétrica, Difração de Raios X, Análise Térmica Diferencial e Análise Granulométrica, para as argilas organofílicas caracterizaram-se por DRX e Fluorescência de raios X por fim foram produzidos fluidos não aquosos de acordo com normatização da Petrobras para realização dos ensaios reológicos. Os resultados evidenciaram que existe influência da razão argila/tensoativo e da rota alcoólica na reologia dos fluidos de perfuração não aquosa.
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38

Borsenberger, Marc. "Contribution à l’identification de l’interaction paramètres procédés – propriétés d’emploi des produits : Application au forgeage et aux propriétés électromagnétiques d’une roue polaire d’alternateur." Thesis, Paris, ENSAM, 2018. http://www.theses.fr/2018ENAM0015.

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La conception de machines électriques tend à intégrer l’impact des procédés de fabrication dans le but d’optimiser la conversion d’énergie mécanique en énergie électrique, en lien avec la maîtrise des propriétés électromagnétiques des composants des machines. Les interactions entre procédés, propriétés électromagnétiques et autres propriétés du matériau ont beaucoup été étudiées dans le cas des tôles compte tenu de leur large utilisation dans le domaine de l’électrotechnique et des moyens de caractérisation magnétique normalisés actuels. Cependant, un alternateur à griffes, utilisé dans l’industrie automobile, comporte des composants massifs au rotor pour la conversion mécanique/électrique. Ces composants, appelés roues polaires, sont obtenus par un processus de fabrication comprenant des opérations de forgeage et dont l’impact sur les performances de la machine est encore mal déterminé. Les nouvelles problématiques que pose ce genre de pièces ont mené, dans le cadre des présents travaux, au développement d’une méthodologie spécifique comprenant : l’identification du lien procédés – produit, le développement d’un banc de caractérisation magnétique d’échantillons représentatifs ainsi que la construction de lois de comportement sur des paramètres matériau pertinents à partir de ces échantillons. Les résultats, en accord avec la littérature, ont montré un impact fort de la déformation plastique et de la taille de grain sur les propriétés magnétiques. Cela se traduit, une fois les propriétés modifiées intégrées dans la simulation des performances d’un alternateur, par une baisse significative du courant débité
The design of electrical machines aims to integrate the impact of the manufacturing process in order to optimize the conversion from mechanical to electrical energy, with the consideration of the electromagnetic properties of the machine components. The interactions between processes, electromagnetic properties and other material properties have been well studied in the case of the steel laminations, regarding their wide use in electrical engineering and the current standards of magnetic characterization devices. However, the claw pole alternator used in automotive industry has a rotor with massive components for the mechanical-to-electrical energy conversion. These components, called claw poles, are manufactured with forging operations whose impact on the machine performance is yet not well determined. The new challenges brought by this kind of work pieces led, in the frame of the current study, to the development of a specific methodology involving: identification of the link process – product, designing of a magnetic characterization device specific for representative samples as well as the establishment of behavior laws regarding relevant material parameters. The results, in accordance with the literature, have shown a strong influence of plastic strain and grain size on magnetic properties. Once these modified properties integrated in the electromagnetic model of the claw pole alternator, a significant decreased of the output current is eventually observed
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39

Bortolini, Débora Gonçalves. "Influência da adição do bagaço imobilizado na evolução dos compostos fenólicos durante o processo fermentativo de mosto de maçã." Universidade Estadual de Ponta Grossa, 2018. http://tede2.uepg.br/jspui/handle/prefix/2487.

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A maçã, uma das frutas mais produzidas no mundo, tem sido consumida de diferentes formas, como em frutas in natura, sucos, produtos fermentados como sidras, bebidas destiladas, vinagres, além de geleias e frutas desidratadas. O aumento da escala de produção de sucos e sidras leva ao incremento da geração do bagaço. Este resíduo caracteriza como sendo uma fração rica em fibras, açúcares e compostos fenólicos com atividade antioxidante que não são totalmente extraídos durante o processamento. Portanto, o bagaço apresenta potencial para ser utilizado no melhoramento da qualidade de alimentos e bebidas. O objetivo deste trabalho foi estudar a extração de compostos fenólicos do bagaço de maçã imobilizado durante a fermentação de sidras, bem como, a evolução destes compostos no decorrer da fermentação e seu impacto na qualidade sensorial. Foram utilizadas maçãs da cultivar Fuji para produzir 20 sidras, as quais foram divididas em dois grupos: sidra I, controle ou sem adição de bagaço imobilizado, e sidra II, com adição de bagaço imobilizado. A fermentação das sidras foi interrompida, em duplicata, nos dias 1, 4, 7, 11 e 15 de fermentação, obtendo duas frações: as sidras e os bagaços fermentados, os quais foram submetidos a extrações consecutivas em metanol e acetona para análise da composição fenólica. Foram realizadas análises de nitrogênio total, cor, pH, acidez total, composição fenólica total, atividade antioxidante, além de composição fenólica individual, composição de açúcares, etanol e sorbitol por CLAE. Também foi realizada análise sensorial com 8 julgadores conhecedores do produto, onde foram avaliados os atributos de acidez, amargor, adstringência, cor e qualidade do odor por meio de escalas estruturadas. Foi observado uma redução do pH e aumento da acidez das sidras no decorrer da fermentação. Durante a fermentação foi observado um decréscimo de 40% dos compostos fenólicos totais da sidra I, o que pode estar relacionado à adsorção dos compostos na parede celular de leveduras e a bioconversão de compostos. No entanto, a sidra II apresentou 93 mg/L a mais de compostos fenólicos totais do que a sidra I, devido a extração desses compostos do bagaço, e por conseqüência, maior atividade antioxidante. Flavonoides, especialmente os flavonóis (quercetina-3-rutinosídeo, quercetina-3-Dgalactosídeo, quercetina-3-β-D-glucosídeo, quercetina-3-D-xilosídeo, quercetina-O-α-Larabinofuranosideo e quercetina-3-O-raminosídeo) foram a principal classe de compostos extraída. Além disso, ocorreu uma extração de açúcares, no início da fermentação da sidra II, o que impactou no seu teor alcoólico que foi mais alto do que na sidra I. Foi observado um residual de frutose nas sidras, o qual foi 0,3 g/L superior na sidra II. A cor de ambas as sidras foi amarela (h° próximo 90°), porém, a sidra II apresentou maior luminosidade. Segundo os resultados da análise sensorial, a sidra II foi mais amarga e menos ácida e a cor foi mais clara. A adstringência das duas bebidas não apresentou diferença significativa (p > 0,05). A qualidade do odor foi avaliada por método afetivo, sendo que ambas as sidras receberam notas entre “gostei ligeiramente” e “gostei moderadamente”. Nos bagaços residuais, após a fermentação, como esperado houve uma redução da quantidade de fenóis e da atividade antioxidante. Também foi observado um aumento na quantidade de nitrogênio no resíduo, devido à retenção de leveduras e também pela extração de compostos como açúcares, o que pode concentrar outros constituintes. Portanto, a utilização do bagaço imobilizado na fermentação pode melhorar a qualidade sensorial de sidras, diminuindo a percepção da acidez, aumentando o amargor e melhorando a cor da bebida, sem alterar a percepção da adstringência, além de aumentar a sua composição fenólica e atividade antioxidante.
The apple, one of the fruit more produced in the world, has been consumed in different ways, such as in raw fruits, juices, fermented products such as cider, distilled beverages, vinegar, as well as jams and dried fruits. The increase of the production scale of juices and ciders leads to increase of apple pomace production. This by-product characterizes as a fraction rich in fibers, sugars and phenolic compounds with antioxidant activity which are not totally extracted in the process. Therefore, the apple pomace shows potential to be used to improve the quality of foods and beverages. The aim of this work was to study the extraction of phenolic compounds from apple pomace immobilized during the fermentation of ciders. As well as, the evolution of this compounds during the fermentation and their impact on sensorial quality. It was used apples from Fuji variety to make 20 ciders, which were divided in 2 groups: cider I, control or without apple pomace addition, and cider II, with addition of apple pomace immobilized. The ciders fermentation were stopped, in supplicate, in the 1st, 4th, 7th, 11th and 15th days of fermentation, obtaining 2 fractions: the ciders and the fermented apple pomace, which were submitted to two consecutive extractions of methanol and acetone to phenolic composition analysis. It were carried out analysis od total nitrogen, color, pH, total titratable acidity, total phenolic composition, antioxidant activity, as well as individual phenolic composition, sugars, ethanol and sorbitol by HPLC. It was also carried out sensory analysis with 8 judges that knew the product, where it was evaluated the attributes of sourness, bitterness, astringency, color and odour quality by structured scales. It was observed a decrease of pH and an increase of titratable acidity of the ciders during fermentation. During the fermentation it was observed a reduction of 40% of total phenolic compounds of cider I, which can be relationed with the adsorption of compounds on cell wall of yeasts and the bioconversion of compounds. However, the cider II showed 93mg/L more total phenolic compounds than cider I, due the extraction of this compounds from apple pomace, and consequently, higher antioxidant activity. Flavonoids, especially flavonols (quercetin-3- rutinoside, quercetin-3-D-galactoside, quercetin-3-β-D-glucoside, quercetin-3-D-xyloside, quercetin-O-α-L-arabinofuranoside e quercetin-3-O-rhaminoside) was the main class of compounds extracted. Furthermore, occurred a extraction of sugars, in the beginning of fermentation of cider II, which impacted on their alcoholic degree which was higher on than cider I. It was observed a residual of fructose on ciders which was 0.3 g/L higher on cider II. The color of both ciders were yellow (h° near 90°), however, cider II showed higher lightness. Second the sensorial analysis results, the cider II ware more bitter and less sour, and their color was more light. The astringency for both beverages did not show significative difference (p > 0.05). the odour quality was evaluated by affective method, being the both ciders received notes between “ I liked quickly” and “I liked moderately”. In the residual apple pomaces, after fermentation, as expected had a reduction of the quantity of phenols an antioxidant activity. It was also observed an increase of total nitrogen, due the yeasts cell retention and also by extraction of sugars, which can concentrate other constituents. Therefore, the use of immobilized apple pomace on fermentation can improve the sensorial quality of ciders, reducing the perception of sourness, increasing the bitterness e improving the color of the beverage, without modify the perception of astringency, futhermor uncrease their phenolic composition and antioxidant activity.
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40

Lavillonnière, Flore. "Rôle des acides gras diènes conjugés (CLA) dans la cancérogenèse mammaire : recherche dans les produits laitiers : étude expérimentale chez le rat et descriptive dans le cancer du sein." Tours, 1998. http://www.theses.fr/1998TOUR3308.

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Notre travail de recherche sur l'acide linoléique conjugué (CLA) avait pour objectif l'étude d'une source alimentaire potentiellement intéressante, les fromages, et d'évaluer leurs propriétés anticancérogènes tant sur un modèle animal que chez des patientes atteintes d'un cancer du sein. L'utilisation de méthodes analytiques diverses, chromatographie en phase gazeuse, liquide, spectrométrie de masse, spectrométrie infrarouge, ont permis d'identifier de façon fiable 14 isomères de CLA en caractérisant la position et la géométrie des insaturations. Cette méthode de dosage des CLA a été utilisée pour évaluer la teneur en CLA des fromages français. Ces fromages, représentatifs ,des diversités régionales et technologiques, contenaient des quantités importantes de CLA (5 à 15 mg de CLA /g de matière grasse), avec un isomère principal, le 18:2 9c,llt (86 à 91 %). Certains paramètres de fabrication (traitement mécanique ou thermique du caillé, durée d'affinage) se sont avérés moduler faiblement la teneur finale en CLA des fromages. En revanche, notre étude souligne l'influence de la nature de l'alimentation des vaches sur la teneur en CLA du lait. Notre étude sur la cancérogenèse mammaire chez le rat et notre étude cas-témoins montrent que l'effet des ALC sur la cancérogenèse mammaire déjà observés expérimentalement pourraient être communs aux rongeurs et à l'humain. L'isomère majoritaire de notre alimentation, le 18:2 9c,llt a montré des propriétés anticancérogènes chez la ratte (réduction du nombre de tumeurs et de la masse tumorale). Chez la femme, le taux de CLA dans le tissu adipeux mammaire est associé à une diminution du risque de cancer du sein (d'un facteur 7). L'isomère 18:2 9c,llt représentant environ 90% des CLA présents dans le tissu adipeux mammaire, il est concevable que cet isomère soit également biologiquement actif chez la femme. Cette étude a permis d'élaborer une méthode fiable d'analyse des CLA et d'éclairer l'origine de la variabilité de leur teneur dans les produits laitiers. De plus, nos résultats suggèrent que l'isomère principal de l'alimentation, le 18:2 9c,11t, parait être biologiquement actif en cancérogenèse mammaire expérimentale chez le rat et pourrait servir de cible pour une prévention nutritionnelle du cancer du sein.
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Chaves, Leonardo Flamarion Marques. "Estudo da adi??o do res?duo proveniente da extra??o de min?rio de ferro em argilas do Rio Grande do Norte." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12749.

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The mining industry is responsible for the generation of waste from their natural process of extraction. The mining impacts in urban areas are of special importance due to the high urban occupation, which are exacerbated due to the proximity of the mined areas and populated areas. Some solutions to wastedisposal have the potential to significantly reduce the environmental risks and liabilities, but represent higher costs in the stages of deployment and operation. The addition of mining waste as raw material in the development of commercial products reduces the environmental impacts, transforming the waste into a positive element in the generation of employment and income. This thesis studies the incorporation of waste iron ore in two clays, one from the ceramic industry of the City of Natal and the other from the ceramic industry of the Serid? Region, both in the State of Rio Grande do Norte, Brazil. Percentages of iron ore waste of 5%, 10% , 15%, 20%, 25% and 30% were used in the tested ceramic matrix. The two clays and the iron ore waste used as part of this investigation were characterized by X-ray diffraction tests, X-ray fluorescence tests, differential thermal analysis, thermogravimetric analysis and dilatometric analysis. The samples were sintered under temperatures of 850 ?C, 950 ?C and 1050?C at a heating rate of 5 ?C/min with isotherms of two hours. The following tests were performed with the samples: linear shrinkage, water absorption, apparent porosity, apparent density, mass loss in fire and bending resistance in order to obtain their physical and mechanical properties. An amount of 5% of waste iron ore in the matrix clay at a temperature of 850 0C resulted in na increase of about 65% in the tensile strength of the clay samples from the Natal ceramic industry. A linear shrinkage of only 0.12% was observed for the samples, which indicates that the physical properties of the final product were not influenced by the addition of the waste
A ind?stria extrativa mineral ? respons?vel pela gera??o de res?duos provenientes do seu processo natural de extra??o. Os impactos da minera??o em ?rea urbana revestem-se de especial import?ncia devido ao alto grau de ocupa??o urbana, que s?o agravados face ? proximidade entre as ?reas mineradas e as ?reas habitadas. Algumas solu??es de disposi??o de res?duos t?m potencial de reduzir significativamente os riscos e o passivo ambiental, por?m representam custos elevados nas etapas de implanta??o e de opera??o. A adi??o de res?duos de min?rio de ferro como mat?ria-prima na elabora??o de produtos que s?o utilizados comercialmente tem como objetivo diminuir os impactos ambientais, transformando esses res?duos em elementos positivos na gera??o de trabalho e renda. O presente trabalho estuda a incorpora??o de res?duo de min?rio de ferro em duas argilas, uma do p?lo cer?mico da Grande Natal e outra do p?lo cer?mico da Regi?o do Serid?, ambas do Estado do Rio Grande do Norte, em percentuais de 5%, 10%, 15%, 20%, 25% e 30%, com o intuito de verificar a potencialidade da incorpora??o do res?duo em matriz cer?mica. As mat?rias-primas foram caracterizadas atrav?s dos ensaios de difra??o de raios X, fluoresc?ncia de raios X, an?lise t?rmica diferencial, an?lise termogravim?trica e an?lise dilatom?trica. Os corpos-de-prova foram conformados e em seguida sinterizados nas temperaturas de 850 ?C, 950 ?C e 1050 ?C, ? taxa de aquecimento de 5 ?C/min, com iso terma de duas horas. Foram realizados os ensaios tecnol?gicos de retra??o linear de queima, absor??o de ?gua, porosidade aparente, massa espec?fica aparente, perda demassa ao fogo e tens?o de ruptura ? flex?o, com o intuito de se obter suas propriedades f?sicas e mec?nica. A argila do p?lo cer?mico da Grande Natal apresentou um aumento em torno de 65% na tens?o de ruptura ? flex?o, com um percentual ?nfimo de 0,12% na sua retra??o linear de queima, quando adicionados 5% de res?duo de min?rio de ferro na matriz de argila ? temperatura de 850 ?C, n?o comprometendo assim as p ropriedades f?sicas do produto final
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42

Paim, Clésio Soldateli. "Mesilato de gemifloxacino : desenvolvimento e validação de métodos analíticos, teste de dissolução e estudo de estabilidade." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/60371.

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A análise de fármacos é fundamental nas diversas fases do desenvolvimento farmacêutico, tais como em estudos de formulação, estabilidade e controle de qualidade do produto. O mesilato de gemifloxacino (MGF), liberado para uso clínico no Brasil em novembro de 2006 com o nome comercial de Factive®, é uma fluorquinolona indicada para o tratamento da exacerbação aguda da bronquite crônica e da pneumonia adquirida da comunidade. A literatura pesquisada apresenta poucos relatos de determinação quantitativa e de estudos de estabilidade do fármaco em comprimidos revestidos. Anteriormente aos estudos, foi realizada a caracterização da substância química de referência (SQR) de MGF por espectrofotometria no infravermelho (E IV), ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono (RMN 13C), análise térmica por calorimetria exploratória de varredura (DSC) e determinação da faixa de fusão. Métodos analíticos para determinação qualitativa e quantitativa foram desenvolvidos e validados por espectrofotometria na região do ultravioleta (E UV) e visível (E VIS), cromatografia líquida de alta eficiência (CLAE), eletroforese capilar (EC) e ensaio microbiológico pelo método de cilindros em placas. A validação de um método de dissolução baseado em dados in vivo do fármaco também foi realizada. A elucidação do produto de degradação isolado em condições alcalinas foi realizada por E IV, RMN de 1H, 13C e correlação (COSY, HSQC e HMBC), espectrometria de massas (EM) e emissão atômica. Estudos de citotoxicidade, fototoxicidade, genotoxicidade e fotogenotoxicidade foram empregados para conhecimento da toxicidade dos produtos analisados.
The drug analysis is essential in all areas of the pharmaceutical development, such as during formulation studies, stability and quality control of the product. Gemifloxacin mesylate (GFM), approved for clinical use in Brazil in November of 2007 with the commercial name of Factive®, is a fluoroquinolone prescribed for the treatment of acute exacerbations of chronic bronchitis and community-acquired pneumonia. The research literature shows a few studies of quantitative determination and stabilities studies of the drug in coated tablets. Previously, it was performed the characterization of the reference chemical substance of GFM by infrared spectrometry (IR), nuclear magnetic resonance of 1H (1H NMR) and 13C (13C NMR), thermal analysis by differential scanning calorimetry (DSC) and determination of the melting range. Analytical methods for qualitative and quantitative determination were developed and validated by ultraviolet (UV) and visible (Vis) spectrophotometry, highperformance liquid chromatography (HPLC), capillary electrophoresis (CE) and microbiological assay applying the cylinder–plate method. The validation of the dissolution method based on in vivo data of the GFM was also performed. The elucidation of the isolate degradation product in alkaline conditions was performed by IR, 1H, 13C and correlation (COSY, HSQC and HMBC) NMR, and mass spectrometry (MS). Cytotoxicity, phototoxicity, genotoxicity and photogenotoxicity studies were carried out for the toxicity knowledge of the analyzed products.
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43

Benvenutti, Laís. "AVALIAÇÃO DA EXTRAÇÃO DE COMPOSTOS FENÓLICOS DO BAGAÇO DE MAÇÃ COM ETANOL PARA APLICAÇÃO EM SIDRA." Universidade Estadual de Ponta Grossa, 2018. http://tede2.uepg.br/jspui/handle/prefix/2465.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A maçã apresenta alta concentração de compostos fenólicos, distribuídos em diferentes classes as quais apresentam capacidade antioxidante. Além disso, conferem efeito positivo na formação do sabor, cor e aroma em bebidas derivadas da fruta. No entanto, durante o processamento, parte da composição fenólica fica retida no bagaço, principal subproduto da agroindústria da maçã. Desta forma, este trabalho teve como objetivo a otimização da extração de compostos fenólicos presentes no bagaço da maçã utilizando solvente de grau alimentício, visando sua aplicação em sidras a fim de melhorar as características tecnológicas, nutricionais e sensoriais do produto final. Nos ensaios de extração foram avaliados os efeitos da concentração de solvente (etanol), temperatura e razão sólido/líquido sobre o rendimento e atividade antioxidante dos extratos, utilizando o método de superfície de resposta (MSR). Além disso, foi estudada a cinética da extração, bem como a estabilidade do extrato. A análise de regressão linear múltipla acoplada ao MSR sugeriu que a extração seja efetuada utilizando etanol 60%, a 50 °C, na razão sólido/líquido de 1:20 (m/v). Por meio de um modelo cinético de primeira ordem foram avaliados os efeitos do tempo e da temperatura sobre a concentração de equilíbrio da extração, a qual foi atingida aproximadamente aos 50 minutos, independente da temperatura, com teores de 1852,77; 1728,35 e 1265,29 mg CAT/kg para as temperaturas de 50, 35 e 20 °C, respectivamente. A partir desses resultados, a energia de ativação necessária para que ocorra a transferência do soluto foi 9,01 kJ/mol. Em geral, os flavonoides apresentaram boa estabilidade durante período de 90 dias, sendo sugerido armazenamento ou aplicação sob temperatura de 10 °C em pH de aproximadamente 3,5. O extrato obtido nas melhores condições foi adicionado ao mosto antes do inóculo de levedura e a fermentação foi monitorada por meio do estudo cinético. Os mostos e pontos da fermentação (1, 4, 7, 11 e 15 dias) foram avaliados quanto aos fenóis individuais, açúcares e etanol em cromatografia líquida de alta eficiência (CLAE). Além disso, foi avaliada a composição fenólica total, flavonoides totais, flavanóis, flavonóis e atividade antioxidante, bem como, o teor de acidez total titulável, pH e cor. Os produtos finais foram analisados sensorialmente quanto à intensidade de cor, acidez, adstringência e amargor por meio de uma escala estruturada, e quanto à qualidade do odor em escala hedônica de aceitação. A adição do extrato aumentou cerca 40% a concentração de flavonoides totais, apresentando glicosídeos de quercetina, compostos presentes apenas no epicarpo da maçã, os quais foram um dos compostos relacionados com o aumento da atividade antioxidante na sidra com adição de extrato. A adição do extrato também resultou em maior intensidade de cor e percepção do amargor e adstringência. Apesar das alterações na composição fenólica, a adição do extrato não prejudicou a qualidade do odor do produto final. Portanto, o extrato fenólico obtido com etanol em condições otimizadas foi capaz de reincorporar parte dos compostos bioativos retidos no bagaço, aumentando a capacidade antioxidante e alterando características sensoriais responsáveis pela aceitabilidade da bebida.
Apple has high amounts of phenolic compounds, distributed in different classes which show antioxidant capacity. In addition, the phenolic compounds contribute to flavor, color and aroma in apple beverages. However, most of the phenolic compounds, especially the flavonoids, are retained in the apple pomace, during processing. In this way, this work aimed to optimize the flavonoids extraction from apple pomace using food grade solvent, and to apply the extracts in ciders in order to improve the technological, nutritional and sensorial characteristics of the final product. In the extraction experiments, the effects of solvent concentration (ethanol), temperature and solid/liquid ratio on process yield and antioxidant activity of the extracts were evaluated using response surface methodology (RSM). In addition, the extraction kinetics as well as the stability of the extract were studied. The multiple linear regression analysis coupled to RSM suggested that the extraction be performed using ethanol 60% at 50 °C and with solute-solvent ratio of 1:20 (w/v). The effects of time and temperature on the equilibrium concentration of the extraction were evaluated, which was reached at approximately 50 minutes with contents of 1852.77; 1728.35 and 1265.29 mg CAT/kg for the temperatures of 50, 35 and 20 ° C, respectively. The activation energy required for solute transfer to occur was determined, 9.01 kJ mol-1. In general, the flavonoids showed good stability during the period of 90 days, being suggested its storage or application under a temperature of 10 °C and pH about 3.5. The extract obtained under the best conditions was added to the must prior to addition of the yeast inoculum and the fermentation was monitored by kinetic study. The musts and ciders (1, 4, 7, 11 and 15 days) were evaluated as to the individual phenols and sugar and ethanol contents were quantified in high performance liquid chromatography (HPLC). In addition, the total phenolic composition, total flavonoids, flavanols, flavonols and antioxidant activity, as well as total titratable acidity, pH and color were evaluated. The final products were sensorially analyzed for color intensity, acidity, astringency and bitterness by means of a structured scale. The odor quality was evaluated in a hedonic scale of acceptance. The addition of the extract increased about 40% in the total flavonoid content. Quercetin glycosides, compounds present only in the apple epicarp, were found, being one of the compounds associated for the increase in antioxidant activity. The cider with the extract addition showed higher intensity of color and perception of the bitterness and astringency. Despite the changes in phenolic composition, the addition of the extract did not affect the odor quality of the final product. Therefore, the phenolic extract obtained with ethanol under optimized conditions was able to reincorporate bioactive compounds retained in the pomace, increasing the antioxidant capacity and changing sensorial characteristics responsible for the acceptability of the beverage.
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44

Björklund, Malin. "Terracotta Vessels : Food storage addressing global challenges." Thesis, Konstfack, Industridesign, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-7848.

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Terracotta vessels are about understanding how we can store food by using a new product solution and how we could use less energy and waste less food in doing so. This project is an attempt to minimise the energy usage in our homes but also to gain greater understanding about the food we choose to bring into our homes and what we can do to avoid throwing it away.
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45

Mitchley, Mark Allan. "Identification and evaluation of the key factors affecting the sustainable export of clay products by South African clay brick manufacturers." Thesis, 2003. http://hdl.handle.net/10413/4024.

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The South African Clay Brick Industry has experienced major change in the last 9 years. Industry driving forces such as globalization, low industry growth rates and government policy changes have affected the local industry as have the bank interest rates and the relative weakness of the SA currency. These industry-driving forces have resulted in a number of local producers undertaking exports of products. The research underlying this report had a threefold objective: a) To identify the key factors affecting the sustainable export of clay products by SA producers. b) To evaluate the key factors affecting the sustainable exports of products by SA producers. c) To utilize the information gathered to identify the critical success factors that support or discourage export development in the Clay brick Industry. The key factors were also used to develop a export success model and assist the aspiring exporter through the process. In order to research the key success factors, it was necessary to firstly analyze modern business strategy and evaluate the chosen strategy. Thereafter, an industry analysis was carried out and the present situation within the industry evaluated. Research was conducted by means of a questionnaire and selected interviews with the industry. The results from the research make it possible to reach conclusions regarding critical success factors and specific factors that will assist the industry in its export drive. The research also identified a host of government -sponsored export incentives that will support the industry in growing exports. Finally, a number of recommendations were made that will go a long way in addressing industry challenges.
Thesis (MBA)-University of Natal, Durban, 2003.
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46

Chan, Ming-Yueh, and 詹明月. "The study of Disinfection by-products(DBPS) catalyed by exchangable cations of clay." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/72251485056583521443.

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碩士
國立中央大學
環境工程研究所
92
Abstract The mechanism of organic compound chlorination during drinking water purification process is complicated. General speaking, in presence of cation in either clay or solution may cause a significant increase in formation of disinfection by-products(DPBs). In our earlier studies, the effects of the different exchangeable cations on clay surface to catalyze chlorinated reaction of organic compounds have ever been elucidated. However, the importance for the exchangeable cation amount in the chlorination reaction needs to be described further. For this reason, the montmorillonite with Ca2+ exchanged by different amounts of cation, including Cu2+, Fe3+,and Ti4+, was employed as the catalyst to examine the product using the NaOCl chlorination humic acid or polymer under a series of batch experiments. A comparable result between cation on the montmorillonite and free cation in the solution was observed to discuss the mechanism of organic compound chlorination. The results indicated that the total formation potential of disinfection by-products (DBPs) for cation-montmorillonite is in the following order :Ti-Mont> Fe-Mont> Cu-Mont> Mn-Mont> Ca-Mont. For the free cation, the order is TiCl4 > FeCl3> FeCl2> CuCl2> MnCl2 >CaCl2> CuCl. The similar result was attributed to that the transition-mental cations process an empty d-orbital, especially in a higher valence state, to act as strong Lewis acid sites and electron acceptors, leading to higher valence state, on the other hand, although the higher amount of the exchange cation can promote the DBPs, the increase trend is unapparent relative to different metal species. The result can be concluded that cation species on the clay is a dominant factor due to they offer a catalytic center where the reaction occur Keyword: catalysis, clay, chlorination , disinfection by-products (DBPs)
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47

"In Vitro and In Vivo Assessment of the Mechanism of Action and Efficacy of Antibacterial Clays for the Treatment of Cutaneous Infections." Doctoral diss., 2014. http://hdl.handle.net/2286/R.I.24926.

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abstract: The prevalence of antibiotic resistant bacterial pathogens has increased since the introduction of penicillin in the 1940s. Insufficient development of novel antibacterial agents is leaving us with a failing arsenal of therapies to combat these pathogenic organisms. We have identified a clay mineral mixture (designated CB) that exhibits in vitro antibacterial activity against a broad spectrum of bacterial pathogens, yet the antibacterial mechanism of action remains unknown. Antibacterial susceptibility testing of four different clay samples collected from the same source revealed that these natural clays had markedly different antibacterial activity. X-ray diffraction analyses of these minerals revealed minor mineralogical differences across the samples; however, ICP analyses demonstrated that the concentrations of many elements, Fe, Co, Cu, Ni, and Zn in particular, vary greatly across the four clay mixture leachates. Supplementation of a non-antibacterial leachate containing lower concentrations of Fe, Co, Ni, Cu, and Zn to final ion concentrations and a pH equivalent to that of the antibacterial leachate resulted in antibacterial activity against E. coli and MRSA, confirming the role of these ions in the in vitro antibacterial clay mixture leachates. The prevailing hypothesis is that metal ions participate in redox cycling and produce ROS, leading to oxidative damage to macromolecules and resulting in cellular death. However, E. coli cells showed no increase in DNA or protein oxidative lesions and a slight increase in lipid peroxidation following exposure to CB-L. Supplementation of CB-L with ROS scavengers eliminated oxidative damage in E. coli, but did not rescue the cells from killing, indicating that in vitro killing is due to direct metal toxicity and not to indirect oxidative damage. Finally, we ion-exchanged non-antibacterial clays with Fe, Co, Cu, and Zn and established antibacterial activity in these samples. Treatment of MRSA skin infections with both natural and ion-exchanged clays significantly decreased the bacterial load after 7 days of treatment. We conclude that 1) in vitro clay-mediated killing is due to toxicity associated directly with released metal ions and not to indirect oxidative damage and 2) that in vivo killing is due to the physical properties of the clays rather than metal ion toxicity.
Dissertation/Thesis
Ph.D. Microbiology 2014
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48

Li, Xujun. "Surfactant enhanced removal of petroleum products from a contaminated soil with sand and clay components." Thesis, 2009. http://spectrum.library.concordia.ca/976399/1/MR63277.pdf.

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The growing energy demand leads to the increasing use of petroleum products. Contaminations caused by uncontrolled release of oil bring risks to the environment. In this study, SDS (sodium dodecyl sulfate), AOT (sodium dioctyl sulfosuccinate) and Brij 35 (polyoxyethylene lauryl ether) are the surfactants selected as washing solutions to remove engine oil from an artificially contaminated soil. The soil was formed using clean sand and montmorillonite clay with different ratios. Contaminated soil samples were formed by contaminating the artificial soil with engine oil which was the chosen petroleum product. Both batch and column tests were conducted to investigate the desorption behavior of engine oil from the contaminated soil. The effects of surfactant type, surfactant concentration, soil composition and pH on desorption efficiency of engine oil were examined in batch experiments. The influences of washing volume and flow rate on oil removal efficiency were investigated in column tests. Distilled water was used as the control. The test results indicate that engine oil solubilization increases with the concentration of surfactants above CMC. In the engine oil removal process, surfactant Brij 35 is more effective than surfactants SDS and AOT. Desorption efficiency of the residual engine oil by 0.6% Brij 35 is almost 20 times higher than that by distilled water. With the same washing volume, lower flow rate appears to be more desirable for oil removal from the contaminated soil.
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49

Χριστογέρου, Αγγελική. "Αξιοποίηση μεταλλευτικών, βιομηχανικών παραπροϊόντων στην παραγωγή δομικών κεραμικών υλικών." Thesis, 2011. http://hdl.handle.net/10889/5070.

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Στην παρούσα διατριβή ερευνήθηκε η αξιοποίηση μεταλλευτικών, βιομηχανικών παραπροϊόντων, των στερεών Υπολειμμάτων Βορίου (ΥΒ), που δημιουργούνται σε διάφορα στάδια κατά την παραγωγική διαδικασία προϊόντων βορίου. Τα εν λόγω παραπροϊόντα, που κατηγοριοποιούνται σε πέντε ποιότητες, SBW, DBW, SSBW, TBW και MBW, χρησιμοποιήθηκαν ως πρόσθετο Α’ υλών για την παραγωγή τούβλων και κεραμιδιών, και ως Α΄ ύλη για την παρασκευή τεχνητών ελαφροαδρανών. Πραγματοποιήθηκε φυσικοχημικός χαρακτηρισμός και θερμική ανάλυση όλων των ΥΒ. Στη συνέχεια μελετήθηκε η επίδραση προσθήκης διαφορετικών συγκεντρώσεων ΥΒ (SBW και SSBW) σε αργιλούχες Α΄ ύλες. Έγινε μια πρώτη προσέγγιση παρασκευής και ελέγχου κεραμικών δοκιμίων με τη μέθοδο της ξηρής ανάμιξης και αξονικής συμπίεσης, προκειμένου να περιοριστεί το φαινόμενο διάχυσης υδατοδιαλυτών ενώσεων βορίου που περιέχονται στα ΥΒ. Η προσθήκη 5%κβ SSBW και θερμοκρασία όπτησης 900-950°C οδήγησε σε κεραμικά με παραπλήσιες ή ακόμα και βελτιωμένες ιδιότητες (αυξημένες μηχανικές αντοχές) συγκριτικά με τα κεραμικά αναφοράς. Επιπλέον εξετάστηκε η παραγωγή δειγμάτων με ΥΒ (SBW) και διάλυμα εμπορίου με βορικό (Evansite®) ακολουθώντας διαδικασία παραπλήσια της βιομηχανικής πρακτικής. Στους 1000°C, παρατηρήθηκε μείωση της απορρόφησης νερού και αύξηση της αντοχής σε κάμψη για τα δείγματα με βορικά, σε σύγκριση με τα δείγματα αναφοράς. Η προσθήκη βορικών ευνόησε τη δημιουργία νέων κρυσταλλικών κατά την όπτηση. Δεδομένης της χημικής και ορυκτολογικής σύνθεσης των ΥΒ (πλούσια σε συλλιπάσματα και υψηλές απώλειες πύρωσης), πραγματοποιήθηκε επιπρόσθετα μελέτη των φυσικοχημικών μηχανισμών θερμικής διάσπασής τους. Σε θερμαινόμενη τράπεζα παρατηρήθηκε η ικανότητα διόγκωσης και ανάπτυξης ρευστής φάσης των ΥΒ, καθώς και μιγμάτων αυτών με άλλα υλικά, με σκοπό την εργαστηριακή παραγωγή ελαφροαδρανών. Βάσει των αποτελεσμάτων προτάθηκε ένα μίγμα αποτελούμενο από 70%κβ ΥΒ, 20%κβ αργιλούχο μίγμα και 10%κβ χαλαζιακή άμμο, για τη μορφοποίηση ξηρών σφαιριδίων. Απότομη θέρμανσή τους στους 760°C οδήγησε σε πορώδη υαλοποιημένα αδρανή με φαινόμενη πυκνότητα <1g/cm3. Το ενεργειακό κόστος παραγωγής των συγκεκριμένων αδρανών είναι χαμηλότερο, καθώς παρατηρήθηκε μείωση στη θερμοκρασία σε σχέση με άλλα τεχνητά ελαφροαδρανή, που παρασκευάζονται στους 1100°C. Για την αντιμετώπιση της διάχυσης ενώσεων βορίου προς την επιφάνεια των ξηρών σφαιριδίων, που οδήγησε σε προβλήματα κατά την πειραματική διαδικασία και σε υποβάθμιση της ποιότητας των τελικών προϊόντων, εξετάστηκε η προσθήκη φρουκτόζης ως παρεμποδιστή στο μίγμα Α’ υλών, με στόχο την βελτιστοποίηση της διαδικασίας παραγωγής ελαφροαδρανών από ΥΒ. Προσθήκη έστω και 0.5%κβ φρουκτόζης οδήγησε σε ικανοποιητικό έλεγχο, ενώ οι φυσικές ιδιότητες των παραχθέντων αδρανών τα κατατάσσουν στην κατηγορία των ελαφροαδρανών, σύμφωνα με το πρότυπο ASTM 330-97. Τα αποτελέσματα οδήγησαν στην κατανόηση βασικών φαινομένων θερμικής διάσπασης και στην ανάπτυξη μιας βέλτιστης διεργασίας παραγωγής τεχνητών ελαφροαδρανών χρησιμοποιώντας ΥΒ ως εναλλακτικές Α’ ύλες, με προφανές ενεργειακό και περιβαλλοντικό όφελος.
In the present thesis, the valorisation of mining and industrial by-products, the solid boron-containing Wastes (ΒW), which are created at various stages during the production process of concentrated and refined boron products, were investigated. The by-products under consideration, existing in five types SBW, DBW, SSBW, TBW and MBW, were used as additives and raw materials in clay mixes for the production of heavy clay ceramics (bricks, tiles and artificial lightweight aggregates). The BW were characterised in means of chemical and mineralogical composition and studied for their thermal behaviour. In addition, clay mixes with different amounts of BW (SBW and SSBW) were studied. A first approach was made on the formation of ceramic samples by dry pressing in order to minimize the borate migration towards the surface. The physical and mechanical properties, as well as the microstructure of the final products were studied. For 5 wt% SSBW addition and firing at 900-950°C, the sintered bodies presented comparable or improved physical and mechanical properties with respect to the reference formulation. Moreover, SBW or a commercial available borate solution (Evansite®) were introduced in a clay-based mix aiming to investigate their behaviour during a processing cycle comparable with that followed in the heavy clay industry. For firing at 1000°C, water absorption was reduced and bending strength increased for the samples with borates, compared to the reference samples. The addition of borates resulted in the formation of new crystalline phases during firing at high temperatures. BW consist of important fluxing oxides as well as of gas producing minerals during firing. Tests were performed on the bloating behavior of BW and mixes of them with other materials, by means of heating microscopy, aiming at the laboratorial production of lightweight aggregates (LWA). A new mix was proposed, according to the obtained results, consisting of 70wt% BW, 20wt% clay mixture and 10wt% quartz sand, for the formation of pellets. Abrupt heating of the dry pellets at 760°C, for 5min, resulted in porous LWA with bulk density <1g/cm3. The process was less energy demanding as the temperature was reduced compared to the one of the synthetic aggregates produced, where the firing temperature is 1100°C. During drying a white layer of boron salts was formed on the surface of the green pellets, which result on firing of a glassy layer causing alterations of their surface and experimental difficulties. In order to address this problem, fructose was added in the raw mix as a migration inhibitor. Addition of even 0.5wt% fructose inhibited the salt formation and a glassy impervious layer was formed after firing. The physical properties of the final samples meet the requirements of LWA according to the standard ASTM 330-97. The results of this thesis, led to the development of an optimised process for the production of artificial LWA with BW, as an alternative raw material.
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50

林明卿. "Apply the Maioli Clay to Speaker Enclosure：A Primary Research on Product Manufacturing and Musical Timbre." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/jjuq78.

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碩士
東海大學
工業設計學系
92
Having clay, natural gases and ceramic production techniques, Miaoli created outstanding decoration ceramic industry in 1989. Meanwhile, the exporting production value of the speaker industry in Taiwan also reached the top. Both ceramic industry and speaker industry are typical OEM exporting industry and labor-intensive but lack of design, brand, and marketing. After Taiwan’s economic development reached a certain level, the basic labor salaries in Taiwan are higher than those of Mainland China and other countries in Southeast Asia that decreases the competition ability of Taiwan manufacturing industry. Facing this difficulty, most of the manufacturing companies in Taiwan are forced to move abroad in order to control their production cost. Under this kind of competition pressure, the manufacturing companies are devoted to research development and the shift of the industry. After a physical and chemical analysis of the Miaoli clay, the clay is used to produce speaker enclosures and test their sound timbre. The sound timbre of the clay enclosures are carefully compared with that of wood enclosures and stone enclosures individually. The test results are shown as follows: 1.The frequency response of clay enclosures is 280 Hz to 16KHz belonging to the range of medium and high sound timbre. 2.When the interior of a clay enclosure is glazed, the enclosure has the function of extending the low frequency response. 3.When the interior of a clay enclosure is glazed or both the interior and the exterior of it are glazed, the enclosure itself has better impedance. 4.The impedance value of the ceramic enclosure is between that of the wooden enclosure and the stone enclosure. 5.The harmonic distortion will be less when the speaker enclosure without glaze or interior and exterior of speaker enclosure are glazed. 6.The harmonic distortion of ceramic speaker enclosure is less than the wood and stone speaker enclosure, but the stone speaker enclosure is the worst . The research results above can have a useful and direct effect in promoting different industries’ cooperation and increasing product value-added.
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