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1
Collins, Shane. "Residue composition influences nutrient release from crop residues." University of Western Australia. School of Earth and Geographical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0171.
Abstract:
[Truncated abstract] A greater adoption of stubble retention, minimum-till and no-till farming practices for the purposes of conserving soil, water and fertility requires a greater understanding of the complexity of physical and chemical interactions between the soil and crop residues. There is currently insufficient knowledge to allow reliable predictions of the effects of different residue types in different environments on soil fertility and crop growth, owing to the many residue characteristics and environmental interactions that have been shown to affect decomposition or nutrient release. The role of fibre and nutrient composition in nutrient release from crop residues, and implications for residue management techniques, were studied. Canola, lupin and field pea residues, obtained from farmland in Meckering and Northam, Western Australia, were separated into upper and basal stems, leaves, and siliques or pods. This was done to provide materials with a wide range of chemical and physical characteristics, and also allowed consideration of differential residue management of plant organs, such as comparing harvested canola siliques and retained canola stubble. Pre-treatment by chopping and/or humidification was applied to residues to provide some information about the processes of nutrient release. Residues were subjected to simulated rainfall to assess nutrient leaching from plant material, and placed on soil in pots in constant-temperature glasshouse conditions to assess decomposition. Amounts and rates of change of residue fibre and nutrients were determined throughout leaching and decomposition. Energy Dispersive X-ray (EDX) microanalysis was used to assess the location of diffusible ions in air-dried residues and the effects of humidification on nutrient positioning and release. ... However, the release of calcium and magnesium depended on the decomposition of the more recalcitrant components such as cellulose and lignin, as supported by microscopy results showing changes in nutrient distribution following humidification. The proportionality of amounts of calcium and magnesium leached and released during decomposition is likely to suggest a similarity of chemical form more than similarity of function or position of the two elements. Management of crop residues for maximising and optimising the timing of release of different nutrients will need to take into account the placement of different plant types and parts, particle sizes distribution and pre-treatment of material to efficiently manage short- and long-term soil fertility to sustain crops, particularly on degraded soils. Significant nutrient release of potassium, sulphur and magnesium from crop residues can be achieved from surface placement, with the release of potassium and sulphur managed by modifying residue particle size through appropriate harvesting, ploughing or sowing implement selection. High nutrient uptake crops and plant parts where they can be economically viable to grow or separated by the harvesting technique are particularly valuable as sources of nutrients and soil organic matter.
2
Alderman, Delton R. Jr. "Assessing the Availability of Wood Residues and Residue Markets in Virginia." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36777.
Abstract:
A statewide mail survey of primary and secondary wood product manufacturers was undertaken to quantify the production and consumption of wood residues in Virginia.
Two hundred and sixty-six wood product manufacturers responded to the study and they provided information on the production, consumption, markets, income or disposal costs, and disposal methods of wood residues. Hardwood and pine sawmills produce approximately 66 percent of Virginia's wood residues. Virginia's wood product manufacturers produce three primary residues: chips, bark, and sawdust. These three residues comprised nearly 83 percent of Virginia's total residue production in 1996. Approximately 200,000 tons or 6 percent of Virginia's wood residues appear not to have adequate markets.
A second survey was directed to all municipal waste, construction and demolition, and "other" waste facilities in Virginia. The focus of this survey was to quantify the volume of solid wood residues received at the facilities. In addition, the study was conducted to ascertain tipping fees, did the landfill(s) actively market wood residues, were wood residues recycled, were wood residues restricted from being landfilled, and disposal methods for wood residues. Additionally, the survey was conducted to determine the type of waste facility operated, the quantity of all wastes directed to each landfill, and tipping fees.
Seventy-five respondents provided information on the total and solid wood waste volumes received at their respective facilities, recycling efforts, and disposal practices. Approximately 689,000 tons of solid wood, or 8 percent of all wastes, was received at Virginia's landfills in 1996. Virginia's waste facilities reported processing or recycling approximately 406,000 tons or 59 percent of the solid wood received in 1996.Master of Science
3
Wallace, James Smyth. "Firearms discharge residues." Thesis, Open University, 1997. http://oro.open.ac.uk/57720/.
Abstract:
The three introductory chapters are intended to summarise the available knowledge prior to the experimental work and to provide useful background information for chemists, with little or no understanding of firearms, who are required to undertake the chemical aspects of firearms casework examination. Chapter 1 provides a much condensed outline of the historical development of firearms and ammunition, with emphasis on ignition systems up to the development of the percussion primer and self contained ammunition. The second chapter presents a comprehensive literature search on the chemical nature of modem ammunition and firearms, with particular attention to priming compositions and projectiles. The final introductory chapter deals with the nature and properties of firearms discharge residues and outlines the most important developments in the search for a satisfactory detection and identification method. The objective of the experimental work is to record experience gained from the 26 year terrorist campaign in Northern Ireland and to use such experience, coupled with further research and development, to substantially improve existing procedures for firearms and explosives residue detection. The experimental work conducted is detailed in Chapter 4. Chapter 5 deals primarily with the Particle Analysis method for the detection and identification of firearms discharge residue, particular attention being directed towards the particle classification system and discharge residue from mercury fulminate and Sintox primed ammunition. Chapter 6 covers suspect handling procedures and contamination avoidance and makes recommendations for permanent improvements in and regular monitoring of the environment in which suspects are sampled. Chapter 7 outlines the development of a method for the detection of the organic constituents of firearms discharge residues, which is compatible with existing inorganic firearms discharge residue and organic explosive residue detection techniques and which enables all suspects to be routinely screened for inorganic and organic firearms discharge residue and organic explosives residue. The final chapter summanses the conclusions, recommendations and comments arising from the work.
4
Quiroz, Christina Carvajal. "Residues and illuminations." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1303238314.
5
Cordeiro, Gustavo Quarezemin [UNESP]. "Tratamento de manipueira em reator anaeróbio compartimentado." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/88424.
Abstract:
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cordeiro_gq_me_sjrp.pdf: 852634 bytes, checksum: afdbb4ebc0a0867ed2c6991e1508045a (MD5)A manipueira, resíduo gerado durante o processamento da mandioca para a produção de fécula ou farinha, é um líquido bastante poluente e tóxico. Para evitar o descarte no meio ambiente, vários estudos estão sendo conduzidos visando minimizar seus efeitos negativos. Um processo bem estudado é o tratamento anaeróbio com separação de fases, uma vez que os reatores em uma única fase mostram-se muito instáveis quanto ao controle da relação acidez/alcalinidade. Para tanto, têm sido utilizados dois reatores, um na fase acidogênica e outro na fase metanogênica para facilitar o controle do processo. Porém, isso acarreta um aumento de espaço de tratamento, uma vez que são duas unidades e a necessidade do controle da alimentação de ambas as fases. Visando eliminar esses inconvenientes, propõe-se o uso de um reator compartimentado, consistindo em uma única unidade e uma única alimentação. Assim, o presente trabalho teve como objetivo avaliar a eficiência no tratamento da manipueira em 10 um reator compartimentado, conhecido na literatura como Anaerobic Baffled Reactor, através da variação da concentração de alimentação e do tempo de residência do sistema. Para isso, utilizou-se um reator de vidro com volume útil de 4,6 litros, constituído de três compartimentos (cada um deles com uma zona descendente e outra ascendente), com cerca de 32% do volume do reator de lodo anaeróbio proveniente de um reator do tipo UASB (upflow anaerobic sludge blanket reactor ou reator anaeróbio de fluxo ascendente com manta de lodo) da planta de tratamento de efluentes da Indústria Arco Íris de Refrigerantes. Após uma etapa de aclimatação, o reator foi alimentado com concentrações crescentes de manipueira (DQO de 1000 a 5000 mg DQO L-1) em diferentes Tempos de Residência Hidráulicos (2 a 6 dias)....
The manipueira, residue generated during the processing of the cassava for the production of starch or flour, it is a sufficiently pollutant and toxic liquid. To prevent the discarding in the environment, some studies are being lead aiming to minimize its negative effect. A well studied process is the anaerobic treatment with separation of phases, a time that the reactors in only phase reveal very unstable unto the control of the relation acidity/alkalinity. For it in such a way, they have been used two reactors, one in the acidogenesis phase and another one in the metanogenesis phase to facilitate the control of the process. However, this causes an increase of treatment space, a time that are two units, the necessity of control and feeding of both phases. Aiming at to eliminate these inconveniences, the use of a baffled reactor is considered, consisting of an only unit and an only 13 feeding. Thus, the present work had as objective to evaluate the efficiency in the treatment of the manipueira in a reactor, known in literature as Anaerobic Baffled Reactor, through the variation of the concentration of feeding and the residence time of the system. For this, a glass reactor was used with useful volume of 4.6 liters, constituted of three compartments (each one of them with a descending zone and another ascendant), with about 32% of the volume of the reactor filled with anaerobic sludge proceeding from a reactor of type UASB (up flow anaerobic sludge blanket reactor) of the effluent treatment plant of the Industry Arco Iris of Cooling. After passing at an acclimatization stage, the reactor was fed with increasing concentrations of manipueira (COD at 1000 to 5000 mg COD L-1) in different Hydraulical Residence Times (2 to 6 days). The control of initial pH was made after two months of experiment, with the sodium bicarbonate addition...(Complete abstract, click electronic address below).
6
Shchuplev, Alexey. "Toric varieties and residues." Doctoral thesis, Stockholm : Department of Mathematics, Stockholm University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6870.
7
Moliner, Estopiñán Cristina Elia. "Valorisation of Agricultural Residues." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/68495.
Abstract:
[EN] The aim of the present PhD Thesis is to define, develop and evaluate a methodology for an improved and more sustainable management of waste, in particular agricultural residues, turning them into a new source of energy and into added value products. Particular attention is paid to the use of rice straw as an energy vector and as a precursor of silica-based compounds.
The recovery of energy was carried through the gasification of biomass within a Spouted Bed Reactor. An initial definition of the main physico-chemical and thermal properties of the feed was performed. The design and operational parameters of the reactor were set according to the characteristics of the biomass. Due to the particular configuration of the reactor, its fluid dynamic properties were analysed in detail in a lab scale unit. The conditions of stability of the reactor and the prevention of segregation phenomena were studied. A scaled-up unit was used for the evaluation of the reactions of gasification of the different residues. The behaviour of the system was modelled at both fluid dynamic and thermo-chemical levels with the aid of different commercial softwares. Finally, a material valorisation was performed. The extraction of silica from the ashes resulting from the thermo-chemical process was studied. Their application as adsorbent materials for the removal of nitrates in water was discussed.[ES] El objetivo de la presente tesis doctoral es definir, desarrollar y evaluar una metodología eficiente de gestión de residuos, en particular agrícolas, para convertirlos en una nueva fuente de energía y en productos de valor añadido. Se estudia con especial atención el uso de la paja de arroz como vector energético y como precursor de productos basados en sílice. Las reacciones de recuperación energética se han llevado a cabo a través de la gasificación de la biomasa en reactores de tipo Spouted Bed. Para ello, se han definido las propiedades físico-químicas y de comportamiento térmico de los residuos estudiados. Los parámetros de diseño y operación del reactor han sido definidos de acuerdo a las características del material tratado. Debido a la particular configuración del reactor, las propiedades fluido- dinámicas del sistema se han analizado en detalle en una unidad a escala de laboratorio. En ella se han estudiado las condiciones de estabilidad del reactor y aquellas que previenen los procesos de segregación. Se ha utilizado una unidad escalada a dimensiones de planta piloto para llevar a cabo las pruebas de gasificacion de los residuos. El comportamiento del reactor se ha modelado tanto a nivel fluido dinámico como a nivel térmico mediante el uso de diversos códigos comerciales de simulación. Finalmente, se ha realizado una valorización material basada en la extracción de sílice de las cenizas resultantes del proceso de valorización térmica. Por último, se han realizado pruebas preliminares de la posible aplicación de dicha sílice en procesos de adsorción de nitratos presentes en agua.
[CAT] L'objectiu de la present tesi doctoral és definir, desenvolupar i evaluar una metodologia eficient de gestió de residus, en particular agrícoles, per convertir-los en una nova font d'energia i en productes de valor afegit. S'estudia amb especial atenció l'ús de la palla d'arròs com a vector energètic i com a precursor de productes basats en sílice. Les reaccions de recuperació energètica s'han dut a terme a través de la gasificació de la biomassa en uns reactors de tipus Spouted Bed . Per això, s'han definit les propietats físico-químiques i de comportament tèrmic dels residus estudiats. Els paràmetres de disseny i operació del reactor han estat definits d'acord a les característiques del material tractat. A causa de la particular configuració del reactor, les propietats fluid - dinàmiques del sistema s'han analitzat amb detall en una unitat a escala de laboratori. S'hi han estudiat les condicions d'estabilitat del reactor i aquelles que prevenen els processos de segregació. S'ha utilitzat una unitat escalada a dimensions de planta pilot per dur a terme les proves de gasificació dels residus. El comportament del reactor s'ha modelat tant a nivell fluid dinàmic com a nivell tèrmic mitjançant l'ús de diversos codis comercials de simulació. Finalment, s'ha realitzat una valorització material basada en l'extracció de sílice de les cendres resultants del procés de valorització tèrmica. Per ùltim, s'han realitzat proves preliminars de la possible aplicació d'aquesta sílice en processos d'adsorció de nitrats presents en aigua.
Moliner Estopiñán, CE. (2016). Valorisation of Agricultural Residues [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/68495
TESIS
Premiado
8
Canettieri, Eliana Vieira [UNESP]. "Obtenção dos parâmetros e estudo cinético da hidrólise ácida dos resíduos florestais de eucalipto." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/106447.
Abstract:
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canettieri_ev_dr_guara.pdf: 1796157 bytes, checksum: 7fcb0f5216d983d4edb448126758bf47 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presenta trabalho visou estabelecer as condições de hidrólise ácida do resíduo florestal de eucalipto a cinética dessa reação. Para atingier os objetivos deste trabalho, foi utilizada metodologia estatística (Planejamento Fatorial e Metodologia de Superfície de Resposta - RSM). A espécie arbórea utilizada neste estudo foi o Eucalyptus grandis de 7 anos de idade. Numa primeira etapa do trabalho, foram realizados ensaios de hidrólise catalisada com ácido em reator de aço inox de 1,4 L de acordo com um Planejamento Fatorial de 2 8-4, para avaliar o efeito de oito variáveis: o tamanho de partícula do resíduo (TR), temperatura (T), tempo de reação (t), umidade do resíduo na solução ácida (E), concentração do ácido (CA), tipo de ácido (A) e relação resíduo/solução ácida (R/A) sobre a extração de xilose da fração hemicelulósica do resíduo de eucalipto. Este estudo revelou que as variáveis significativas foram a temperatura, a concentração do ácido sulfúrico e a relação resíduo/solução ácida para a remoção daxilose da fração hemicelulósica do resíduo de eucalipto na região de estudo... .
The aim of this work was to establish optimal conditions for hydrolysis of eucalyptus forest residues and investigate the kinetics of this reaction. Research was conducted making use of response surface methodology (RSM) and a seven-year old Eucalyptus grandis tree. In the first phase of this work, hydrolysis tests were carried out in a 1,4L stainless steel reactor according to a 2 8-4 fractional factorial design, in order to evaluate the effects of eight variables (residue particle size, temperature, reaction time, residue moisture, soaking of the residue in acid solution, acid concetration, type of acid and ratio of residue/acid solution) on xylose extraction from the hemicellulosic fracation of eucalyptus residue. The results showed that, taking into account the type of reactor utilized, the variables temperature, sulfuric acid concentration and ratio of eucalyptus residue/acid solution in the ranges... (Complete abstract, click electronic address below).
9
Lundqvist, Johannes. "On Amoebas and Multidimensional Residues." Doctoral thesis, Stockholms universitet, Matematiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-82843.
Abstract:
This thesis consists of four papers and an introduction. In Paper I we calculate the second order derivatives of the Ronkin function of an affine polynomial in three variables. This gives an expression for the real Monge-Ampére measure associated to the hyperplane amoeba. The measure is expressed in terms of complete elliptic integrals and hypergeometric functions. In Paper II and III we prove that a certain semi-explicit cohomological residue associated to a Cohen-Macaulay ideal or more generally an ideal of pure dimension, respectively, is annihilated precisely by the given ideal. This is a generalization of the local duality principle for the Grothendieck residue and the cohomological residue of Passare. These results follow from residue calculus, due to Andersson and Wulcan, but the point here is that our proof is more elementary. In particular, it does not rely on the desingularization theorem of Hironaka. In Paper IV we prove a global uniform Artin-Rees lemma for sections of ample line bundles over smooth projective varieties. We also prove an Artin-Rees lemma for the polynomial ring with uniform degree bounds. The proofs are based on multidimensional residue calculus.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 3: Manuscript. Paper 4. Manuscript.
10
Kochersberger, Kevin B. "A method of determining modal residues using an improved residual model and least squares." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/40166.
Abstract:
A new approach to determining mode vectors is presented which uses predetermined global parameters and an improved residual model to iteratively determine modal residues. The motivation for such a technique is to determine modal parameters rapidly so that, as data acquisition techniques become faster, more structural degrees of freedom can be measured without significantly slowing down the parameter estimation process.
The technique requires an accurate determination of the global parameters of natural frequency and damping by means of an FRF curve fit. More than one structural point is recommended to determine the global parameters since they will be used in determining the mode vectors. A structurally damped curve fitter which uses one or two FRFs is described and can be used for determining the global parameters. Examples of curve fitting simulated and measured data are presented and a comparison is made to a commercially available curve-fitter.
Once a frequency range-of-interest is selected, frequencies will be chosen at which the mobility is measured using sine excitation. The in-range modal response is represented by a matrix-vector product where the vector contains the residues for the modes of interest. The out-of-range modal content is also represented by a matrix-vector product and forms the improved residual model. The residual content is removed from the measured mobility by an iterative technique which allows for an accurate determination of the residues of interest.
An evaluation of the technique is carried out by simulating a dynamic system including the shaker and power supply. The simulated system is closely modeled after a real system used to evaluate the technique on experimental data. Convergence rates are shown for cases of close modes, low amplitude modes and errors in the global parameters. The results of using the technique on experimental data shows that convergence typically occurs in under 15 iterations. Regenerating the FRF from the modal parameters shows close agreement to the original FRF and better agreement than the regeneration from modal parameters derived from a commercially available curve fitter.>Ph. D.
11
Vieira, Ana Júlia Rêgo. "Aplicação de processos oxidativos avançados em resíduos contendo hidroquinona." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-13092007-170230/.
Abstract:
Neste trabalho é utilizado o processo oxidativo avançado, via reagente de Fenton, para a destruição de resíduos que contenham hidroquinona. Sendo as técnicas utilizadas para a comprovação desta metodologia: ultravioleta, carbono orgânico total, cromatografia gasosa, cromatografia gasosa acoplada à espectrometria de massas. Em todas essas análises pôde?se observar uma destruição de mais de 60% da hidroquinona.In this work, the destruction of hydroquinone present in residues was reached through advanced oxidation process, via Fenton. The reaction was followed by ultraviolet spectroscopy, total organic carbon and gas chromatography with flame ionization detector and mass spectrometry detector. Throughout all the results, the destruction of hydroquinone was greater than 90%.
12
Lange, Gun. "Pesticide use in rice cultivation in Tarapoto, Peru : pesticide residues in blood of farmers, usage behaviour, and health care practices /." Uppsala : Institutionen för miljöanalys, Sveriges lantbruksuniversitet, 2006. http://epsilon.slu.se/10191555.pdf.
13
Brachi, Paola. "Fluidized Bed Torrefaction of Agro-Industrial Residues: the Case Study of Residues from Campania Region, Italy." Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2187.
Abstract:
2014 - 2015The purpose of this Ph.D. project was to investigate the potential of the torrefaction treatment for upgrading low-value agro-industrial residues into useable solid fuels to be employed as high-quality energy carriers. The first phase of the project involved a screening of the agro-industrial residues available in Campania region (Italy) with good potentiality for energy applications. As a result of this analysis, tomato processing residues and olive mill residues, which have stood out as those in need of a more sustainable and environmental friendly disposal solution, were at first selected as biomass feedstocks for this Ph.D. project. However, practical difficulties encountered in the pre-treatment of the virgin olive husk (i.e., specifically in reducing the size of olives stone fragments which compose olive mill residues together with the olive pulp) led afterwards to discard such residue as a potential feedstock for the subsequent lab-scale torrefaction tests... [edited by author]
XIV n.s.
14
Barker, Andrew Lewis. "Mass Spectrometry-Based Identification of Ceramic-Bound Archaeological Protein Residues: Method Validation, Residue Taphonomy, and Prospects." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404522/.
Abstract:
Despite the variety of successful reports of the preservation, recovery, and identification of archaeological proteins in general, there are few positive reports regarding mass spectrometry-based identification of ceramic-bound proteins. In large part, this shortage is due to the lack of consideration for the unique taphonomic histories of such residues and, in general, methods development. Further, because negative results are rarely published, there is no baseline to which results can be compared. This paper attempts to address these challenges via a multi-pronged approach that uses mass spectrometry and complementary approaches to evaluate ceramic-bound protein preservation in both controlled, actualistic experiments, and in archaeological artifacts. By comparing the results obtained from protein-spiked, experimentally-aged ceramic to those obtained from both faunal and ceramic archaeological materials, an enhanced perspective on protein preservation and subsequent recovery and identification is revealed. This perspective, focusing on taphonomy, reveals why negative results may be the norm for ceramic artifacts when non-targeted methods are employed, and provides insight into how further method development may improve the likelihood of obtaining positive results.
15
volkaner, hacer deniz. "Euler's criterion for n:th power residues." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-12211.
16
Andersson, Patrik, and Carl-Magnus Arvhult. "Metallic residues after hydriding of zirconium." Thesis, KTH, Materialvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-125027.
Abstract:
As a part of the production of nitride nuclear fuel for use in fast nuclear reactors, zirconium is hydrided followed by nitriding and mixing with uranium nitride. This work concludes a study of unwanted metallic particles present in a powder that is supposed to be a zirconium hydride. Sponge zirconium was hydrided at different temperatures and different time intervals, and the resulting hydride was milled into a powder. The powders were analyzed using SEM and XRD after which the powders were pressed into pellets for light optical microscopic study. The primary goals were determination of the structure of the particles and thereafter elimination of them. It was seen that hydriding at 500 C results in less metal particles but more experiments need to be conducted to confirm this.
17
Forton, Osric Tening. "Metal levels in automotive shredder residues." Thesis, University of Brighton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439212.
18
Dai, Peng Ph D. Massachusetts Institute of Technology. "Site-selective modification of cysteine residues." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115793.
Abstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references.
Proteins are biomolecules that carry out essential work in cells and are required for the structure, function, and regulation of biological systems. It is desired to install designer modifications on proteins of interest, in a site-selective manner mimicking nature's post-translational modifications, for various biological and therapeutic applications. Towards this goal, efforts were devoted to develop site-selective protein modification methods. The [pi]-clamp-mediated cysteine perfluoroarylation, a novel sequence-selective protein modification strategy, enabled regioselective cysteine modification in the presence of competing cysteines on protein surface. The major goals of this thesis include improving and understanding the [pi]-clamp-mediated reaction, and discovering new sequence-selective protein modification chemistries. Aiming to improve the n-clamp-mediated site-selective protein modification, the effect of inorganic salts is discovered. Salt in aqueous solution significantly changes the reaction rate of [pi]clamp-mediated cysteine bioconjugation over four orders of magnitude, enabling fast and sitespecific modification of proteins including antibodies. The salt effect on n-clamp-mediated arylation is concentration-dependent and ion-specific following the Hofmeister series. Salts composed of early member ions in the Hofmeister series accelerate the reaction, while late members decrease the rate. To understand the unique self-labelling reactivity of the n-clamp tetrapeptide (Phe-Cys-Pro-Phe), mutational, computational, and structural investigations are carried out. Our findings suggest several structural and chemical features contribute to the unique reactivity of [pi]-clamp including the trans prolyl amide bond, lowered reaction enthalpy of activation ([delta]H**), reduced cysteine pKa and side chain-perfluoroaryl electrophile interactions. A sequence-selective thiol-yne reaction is discovered. The seven-residue peptide tag (DBCO-tag, Leu-Cys-Tyr-Pro-Trp-Val-Tyr) can selectively react with various azadibenzocyclooctyne (DBCO) reagents. To demonstrate the sequence-selectivity, this reaction is applied to site-selective cysteine modificaition in proteins bearing more than one cysteine residue. In addition, organometallic palladium oxidative addition complexes bearing O-phenyl carbamate are developed for protein crosslinking between cysteine and lysine residues. A glutathione S-transferase (GST) catalyzed site-selective macrocyclization reaction for peptides up to 40 amino acids in length is also reported.
by Peng Dai.
Ph. D.
19
Venter, P. "Endotoxin residues in food : a review." Interim : Interdisciplinary Journal: Vol 9, Issue 1: Central University of Technology Free State Bloemfontein, 2010. http://hdl.handle.net/11462/348.
Abstract:
Published ArticleThe initial section of this manuscript focus on the ultra-structure of a unique class of heat stable cell-bound lipopolysaccharides (endotoxin) produced by Gram-negative bacteria. Subsequently, this paper summarises literature on the human body's response when challenged with endotoxins present in food and further explores the influence of food manufacturing and storage practices on endotoxin production and release by bacteria commonly isolated from food. Finally, this paper presents a brief description on the methods applied by the food industry to quantify endotoxins.
20
Ferreira, Rui Manuel Cordeiro. "Creating greater value for biomass residues." Doctoral thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica, 2013. http://hdl.handle.net/10362/12012.
Abstract:
Dissertation presented to obtain the Ph.D degree in Engineering Sciences and TechnologyRenewable resources have been the focus of both the scientific and industrial communities as substitutes for fossil fuels. Numerous studies have addressed the conversion of biomass to value-added chemicals, to materials, to fuels and into power and/or heat, i.e. biorefinery. The main goal of this thesis is to develop alternative extraction processes to isolate value-added constituents from biomass residues. Cork and birch outer bark were selected since the corresponding processing industries generate significant amounts of residues with high contents of value-added compounds, namely suberin (structural component) and triterpenes (extractable components).(...)
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Goralski, Alma. "Removal of pharmaceutical residues from wastewater." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259951.
Abstract:
Today, pharmaceutical residues are widely found in nature as a cause of the extensive use of human and veterinary medicine. The pharmaceutical residues have shown to have a damaging impact on flora and fauna. Wastewater Treatment Plants (WWTPs), today, are not designed for pharmaceutical removal, which calls for new methods and the implementation of these to avoid increased concentrations of pharmaceutical residues in nature. This thesis addresses three main areas. Firstly, a pre-study regarding the prevalence of pharmaceutical residues at different parts of a WWTP and in the nearby river, secondly, an evaluation of removal of pharmaceutical residues using ozone and, thirdly, the construction of a pilot plant scale Activated Carbon (AC) unit and an evaluation of its capacity for pharmaceutical and ozone removal. This work was done in order to verify the quality of a future full-scale unit including the advanced techniques ozone and AC that will be implemented at a WWTP for pharmaceutical removal. The pre-study shows that the total concentration of the Active Pharmaceutical Ingredients (APIs) was largest at the inlet (93.8 mg/L) and decreased throughout the process steps to be the lowest at the outlet (5.6 mg/L). Paracetamol was found in the highest concentration (86.5 mg/L) at the inlet but could not be detected in the outlet. In the recipient none of the APIs could be found. However, caffeine was detected in the recipient. The pilot plant studies were performed in a batch process, one at high ozone generation and one at low ozone generation. The pilot test at high ozone generation showed that all of the measured APIs were below their Limit of Quantification (LOQ) after 2 minutes. The pilot test at low ozone generation showed a total API-removal of 44% after 7 minutes, 78% after 13 minutes, 97% after 20 minutes and more than 99% after 60 minutes. All of the APIs were below their LOQ after 180 min. The AC-filter construction mirrored the conditions within a full-scale unit as closely as possible and was scaled by the superficial velocity. The AC-filter showed an ozone removal of approximately 99% and removed all pharmaceutical residues apart from Ranitidine which was decreased by 76%.Idag återfinns läkemedelsrester i stor utsträckning i naturen, vilket är ett resultat av den omfattande användningen av human- och veterinärmediciner. Läkemedelsresterna har visat sig ha en skadlig effekt på flora och fauna. Dagens avloppsreningsverk är inte byggda för att rena vattnet från läkemedelsrester, vilket kräver att nya metoder utvecklas och implementeras för att förebygga spridning av läkemedel. Denna avhandling redogör för tre huvudområden, inledningsvis en förstudie om förekomsten av läkemedelsrester i olika delar av ett vattenreningsverk samt i en närliggande å. Därefter en studie av ozons förmåga att eliminera läkemedelsrester och slutligen konstruktion av ett aktivt kolfilter och en utvärdering av dess förmåga att ta bort läkemedel. Detta gjordes med syftet att verifiera kvalitén hos en fullskalig anläggning som kommer att installeras på ett vattenreningsverket där ozon och aktivt kol kommer användas för borttagning av läkemedelsrester. Förstudien visar att totalkoncentrationen av de aktiva läkemedelssubstanserna (API:er) var som störst vid inloppet av reningsverket (93.8 μg/L) och koncentrationen minskade genom de olika processtegen och var som lägst i utloppet (5.6 μg/L). Paracetamol återfanns i den högsta koncentrationen i inloppet (86.5 μg/L), men kunde inte detekteras i utloppet. Ingen av API:erna återfanns i recipienten, men däremot detekterades koffein. Pilotanläggningsstudierna genomfördes i en batch och genomfördes med högozongenerering och med låg ozongenerering. Studien med hög ozongenerering visade att alla läkemedelsrester var under analysmetodens detektionsgräns efter 2 minuter. Pilotstudien med låg ozonegenerering visade att den totala läkemedelsborttagningen var 44 % efter 7 minuter, 78 % efter 13 minuter, 97 % efter 20 minuter och mer än 99 % efter 60 minuter. Alla läkemedelsrester var under analysmetodens detektionsgräns efter 180 min. Kolfiltret konstruerades för att efterlikna det fullskaliga filtret så mycket som möjligt och skalades således efter den hypotetiska tomma bäddhastigheten. Kolfiltret tog bort cirka 99 % av ozonet och alla läkemedelsrester utom Ranitidin som reducerades med 76 %.
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Gonzalez, Anselmo Dueñas 1968. "Caracterização e análise comparativa de cinzas provenientes da queima de biomassa." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265872.
Abstract:
Orientador: Caio Glauco SánchezDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: O presente trabalho apresenta o desenvolvimento de um processo de caraterização das cinzas das biomassas bagaço de cana-de-açúcar, eucalipto e capim elefante após sua queima quando utilizadas para geração de energia alternativa. É, então, analisada a influência de parâmetros físico-químicos na qualidade final das cinzas. O parâmetro químico avaliado foi a interpretação da composição elementar das cinzas estudadas por análises de Espectrometria de Fluorescência de Raios-X e Cromatografia de Íons e por Análise Química por, objetivando a caracterização e reutilização desses resíduos. As amostras de cinzas de biomassas estudadas neste trabalho, foram analisadas quanto à presença dos elementos Cloro (Cl-), Alumínio (em Al2O3), Cálcio (em CaO), Ferro (em Fe2O3), Fósforo (em P2O5), Magnésio (em MgO), Manganês (em MnO), Potássio (em K20), Sódio (em Na2O) e Silício (em SiO2), e foram caracterizadas conforme os percentuais em massa dos elementos presentes. Os resultados obtidos mostraram a possibilidade de reutilização adequada de cinzas das biomassas em função da alteração das propriedades químicas do solo, por ocorrência de elevação dos níveis de pH, Cálcio (Ca), Fósforo (P), redução dos teores de Alumínio (Al) trocável e melhoria substancial da capacidade de agregação das partículas e fertilização do solo. Também foram associadas as influências dos elementos presentes nas cinzas como alternativa viável na composição do cimento Portland, em especial, o Silício (em SiO2). As cinzas das biomassas possuem nutrientes que estão na forma solúvel e são libertados ao longo do tempo devido à sua decomposição contínua e também pela solubilidade dos compostos químicos, o que, consequentemente, torna os nutrientes menos suscetíveis à lixiviação
Abstract: This paper presents the development of a process of characterization of the ashes of biomass bagasse from sugar cane, eucalyptus and elephant grass after its burning when used for alternative energy generation. It then analyzed the influence of physicochemical parameters on the final quality of the ash. The chemical parameter evaluated was the interpretation of the elemental composition of the ash studied by analysis Fluorescence Spectrometry X-Ray and Ion Chromatography and Chemical Analysis, aiming at characterization and reuse of the waste. The ashes from biomass samples studied in this work were analyzed for the presence of chlorine (Cl-), aluminum (as Al2O3), calcium (as CaO), iron (as Fe2O3), phosphorus (as P2O5), Magnesium elements (as MgO), manganese (as MnO), Potassium (as K20) Sodium (as Na2O) and silicon (as SiO2), and were characterized as the weight percentage of the elements present. The results showed the possibility of proper reuse of ashes of biomass due to changes in chemical properties of the soil, by the occurrence of elevated levels of pH, calcium (Ca), phosphorus (P), reduced levels of aluminum (l) the significant improvement exchangeable capacity of aggregation of particles and soil fertilization. Were also associated with the influences of the elements present in the ash as a viable alternative in the composition of the Portland cement, in particular, silicon (as SiO2). The ash of the biomass have nutrients that are in soluble form and are released over time due to its continuous decomposition and also by the solubility of the chemical compounds, which consequently makes them less susceptible to leaching nutrients
Mestrado
Termica e Fluidos
Mestre em Engenharia Mecânica
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Canettieri, Eliana Vieira. "Obtenção dos parâmetros e estudo cinético da hidrólise ácida dos resíduos florestais de eucalipto /." Guaratinguetá : [s.n.], 2004. http://hdl.handle.net/11449/106447.
Abstract:
Resumo: O presenta trabalho visou estabelecer as condições de hidrólise ácida do resíduo florestal de eucalipto a cinética dessa reação. Para atingier os objetivos deste trabalho, foi utilizada metodologia estatística (Planejamento Fatorial e Metodologia de Superfície de Resposta - RSM). A espécie arbórea utilizada neste estudo foi o Eucalyptus grandis de 7 anos de idade. Numa primeira etapa do trabalho, foram realizados ensaios de hidrólise catalisada com ácido em reator de aço inox de 1,4 L de acordo com um Planejamento Fatorial de 2 8-4, para avaliar o efeito de oito variáveis: o tamanho de partícula do resíduo (TR), temperatura (T), tempo de reação (t), umidade do resíduo na solução ácida (E), concentração do ácido (CA), tipo de ácido (A) e relação resíduo/solução ácida (R/A) sobre a extração de xilose da fração hemicelulósica do resíduo de eucalipto. Este estudo revelou que as variáveis significativas foram a temperatura, a concentração do ácido sulfúrico e a relação resíduo/solução ácida para a remoção daxilose da fração hemicelulósica do resíduo de eucalipto na região de estudo... (Resumo completo, clicar acesso eletrônico abaixo).Abstract: The aim of this work was to establish optimal conditions for hydrolysis of eucalyptus forest residues and investigate the kinetics of this reaction. Research was conducted making use of response surface methodology (RSM) and a seven-year old Eucalyptus grandis tree. In the first phase of this work, hydrolysis tests were carried out in a 1,4L stainless steel reactor according to a 2 8-4 fractional factorial design, in order to evaluate the effects of eight variables (residue particle size, temperature, reaction time, residue moisture, soaking of the residue in acid solution, acid concetration, type of acid and ratio of residue/acid solution) on xylose extraction from the hemicellulosic fracation of eucalyptus residue. The results showed that, taking into account the type of reactor utilized, the variables temperature, sulfuric acid concentration and ratio of eucalyptus residue/acid solution in the ranges... (Complete abstract, click electronic address below).
Orientador: João Andrade de Carvalho Júnior
Coorientador: João Batista de Almeida e Silva
Banca: Silvio Jorge Coelho Simões
Banca: Luiz Fernando Costa Nascimento
Banca: George Jackson de Moraes Rocha
Banca: Raul Eduardo Piad Barreras
Doutor
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George, Anthe. "The leaching properties of co-combustion residues." Thesis, Imperial College London, 2005. http://hdl.handle.net/10044/1/12027.
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Pretto, Cristine De. "Soybean biorefinery with residues exploitation : process assessment." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8672.
Abstract:
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Soybean seed is a renewable feedstock and the production process of soybean meal and soybean refined oil generates residues that can be exploited, in such a way that the biorefinery concept can be applied to this production process. For this reason, this work aimed to analyse the employment of the biorefinery concept to a soybean crushing and refining facility, exploiting applications for the residues generated during the process. For that, first, information and data from literature about the traditional manufacture process of soybean meal and refined soybean oil were collected and the residues produced during this process were identified. Once the residues were recognized, data in academic literature about possible applications for the residues were collected. Next, the traditional process for producing soybean refined oil and defatted meal was simulated using a commercial simulator. The amounts of residues generated and energetic requirements were calculated. The amount of residues generated during soy protein concentrate (SPC) and soy protein isolate (SPI) process production were also obtained by simulations of these processes. Following, an application for each residue (except for SPI residues) was simulated in the same software and the results were analysed. It was verified that soybean straw and hulls could fulfill the energetic demand of the crushing, refining and biodiesel production process and even a surplus of electricity could be generated, especially when biodiesel was also used as a boiler fuel. Four residues from refining process are generated: gums, soapstock, spent bleaching earth and deodorizer distillate. From gums, it is possible to produce lecithin. From soapstock and spent bleaching earth, biodiesel can be generated, although it generates more residues and consumes more steam than the production of biodiesel from degummed oil. From deodorizer distillate, it is possible to concentrate tocopherols, which is an antioxidant and can be sold for its antioxidant properties. Soybean molasses generated during the concentration of proteins from soybean meal can also be used for electrical energy production.
A soja é uma matéria-prima renovável e o processo de produção de farelo e óleo refinado de soja gera alguns resíduos que podem ser aproveitados, de forma que o conceito de biorrefinaria pode ser aplicado a esse processo produtivo. Dessa forma, esse trabalho objetivou analisar a aplicação do conceito de uma biorrefinaria a uma instalação processadora de soja, buscando aplicação para os resíduos produzidos durante o processo. Para isso, primeiro coletaram-se informações e dados na literatura sobre o processo tradicional de produção de farelo desengordurado e óleo refinado de soja e os resíduos gerados durante esse processo foram identificados. Uma vez identificados os resíduos do processo, dados na literatura acadêmica sobre possíveis aplicações para esses resíduos foram coletados. A seguir, o processo tradicional de produção de óleo de soja refinado e farelo desengordurado foi simulado por meio de um software comercial. A quantidade de resíduos gerados e as demandas energéticas do processo foram obtidas. A quantidade de resíduos gerados durante o processo de fabricação de proteína de soja concentrada (PSC) e proteína de soja isolada (PSI) também foi calculada. Posteriormente, uma aplicação para os resíduos gerados (exceto os resíduos do processo de produção de PSI) foram simulados no mesmo software e os resultados foram analisados. Verificou-se que utilizando a casca e a palha da soja, toda a necessidade energética, tanto térmica quanto elétrica, do processo de produção de farelo, óleo refinado e biodiesel a partir do óleo degomado é satisfeita e até mesmo uma quantidade adicional de energia elétrica pode ser gerada, ainda mais quando o biodiesel também é usado como combustível na caldeira. Quatro resíduos são gerados durante o processo de refino do óleo: gomas, borra, terra clarificante gasta com óleo residual e destilado desodorizado. A partir das gomas, pode-se produzir a lecitina de soja. Da borra e terra clarificante gasta com óleo residual, pode-se produzir biodiesel, mas mais resíduos são gerados e mais vapor é consumido quando comparado à produção de biodiesel a partir do óleo degomado de soja. Os tocoferóis presentes no destilado desodorizado podem ser concentrados e vendidos devido às suas propriedades antioxidantes. O melaço da soja, gerado durante o processo de concentração das proteínas do farelo, também pode ser usado para a geração de energia elétrica.
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Odlare, Monica. "Organic residues - a resource for arable soils /." Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200571.pdf.
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Haag, Jennie, and Anna Landahl. "Pesticide residues in cucumbers cultivated in Bangladesh." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-234741.
Abstract:
Pesticides are widely used for preventing crop losses due to pest attack. In Bangladesh, the food safety and health of farmers are being compromised as a result of poor regulation concerning usage of pesticides in food production. The aim of this study was to identify and quantify pesticides applied on cucumber crops in Bangladesh. A method for extraction and clean-up was developed to allow the quantification of four pesticides by GC-ECD in vegetable samples, specifically cucumber. The accuracy of the method was validated using recovery and its precision by studying the standard deviation and relative standard deviation. Analysis of cucumber samples obtained in the field showed no traces of the target pesticides. The results indicate that different types of chemicals are used on the examined crops. It is also believed that the growth habit of cucumber may affect the exposure to pesticides. To overcome the health hazards, restrictions regarding the types and quantities of chemicals used on the fields need to be implemented. Further studies would benefit from being executed in a controlled environment, and monitoring of which substances that are applied at which amounts.
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McCracken, Robert James. "A study of furazolidone residues in pigs." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337021.
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Cooper, Margaret S. "Anti-cancer peptides containing modified tyrosine residues." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246193.
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Siripong, Chuthathip, and Supusanee Dulyakasem. "Continuous co-digestion of agro-industrial residues." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-16592.
Abstract:
Slaughterhouse waste (SB) has high potential to be utilized in anaerobic digestion due to its high protein and lipid content. However, these are also the limiting factors of system stability. Thus, co-digestion of slaughterhouse waste with other agro-industrial residues (manure (M), various crops (VC) and municipal solid waste (MSW)) was introduced in this study to overcome this problem. The main objective of the work was to determine the operating parameters and the methane yield in semi-continuous co-digestion of slaughterhouse waste with other agro-industrial waste streams. Four continuously stirring tank reactors (CSTRs) with different substrates and mixtures (SB, SB:M, SB:VC and SB:VC:MSW) were started up operating with hydraulic retention time (HRT) of 25 days in thermophilic conditions. The highest organic loading rates which could be achieved were 0.9 g VS/L·d in digestion of SB and 1.5 g VS/L·d for the co-digestion mixtures. In these cases, average methane yields of 300, 510, 587 and 426 ml/g VS were obtained from the digestion of SB, and the co-digestion of SB:M, SB:VC and SB:VC: MSW, respectively, with methane contents in the biogas of 60-85%. The highest average methane yield of 587 ml/g VS was found in co-digestion of SB:VC, which was in accordance with the value of 592 ml/g VS detected during the batch digestion of the same mixture. Moreover, batch assays with different substrates as well as 11 different mixtures of those were also set up to investigate the methane potential and the effect of second feeding. The results showed that the co-digestion of SB:VC, SB:VC:MSW and SB:M could provide high methane potentials, where the highest methane yields of 592, 522 and 521 ml/g VS, respectively were obtained. Moreover, increasing, similar or decreasing methane yields were determined from the second feeding depending on the substrates and substrate mixtures used.Program: MSc in Resource Recovery - Sustainable Engineering
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Chu, Jhih-Wei 1973. "Oxidation of methionine residues in protein pharmaceuticals." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28660.
Abstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2004.Includes bibliographical references (p. 171-189).
(cont.) of free methionine. Therefore, the environments surrounding different methionine sites in G-CSF mainly provide spatial restriction to the access to the solvent but do not affect oxidation in a specific manner, consistent with the good correlation between 2SWCN's and the rates of oxidation. A comprehensive picture of oxidation is thus developed. It allows an accurate prediction of protein oxidation, and provides a rationale for developing strategies to control oxidation, such as modulating protein conformation via adding excipients. This knowledge could aid in developing in a more rational manner solvent formulations that protect therapeutic proteins against oxidation.
Oxidation of the amino acid methionine by peroxides in aqueous formulations of proteins is a critical issue in the development of therapeutic products. It must be controlled so that therapeutic proteins can maintain their activity. In addition, oxidized therapeutics are undesirable due to their possible immunogenetic effects. An understanding of the mechanism and the factors that influence the reactivity of different methionine sites toward oxidation is therefore important. In this thesis, computational methods are applied and developed to address these problems. First, a mechanism by which peroxides oxidize the sulfur atom of methionine is developed. The rate-limiting step was found to be the breaking of the O-O bond of H₂O₂ and the formation of the S-O bond during which significant charge separation is developed. The charge separation can be stabilized via specific interactions such as hydrogen bonding with surrounding water molecules. This "water-mediated" mechanism of oxidation is consistent with experimental data such as those on activation energies of oxidation and pH dependence of the rates of oxidation. Based on the "water-mediated" mechanism, a structural property, average 2-shell water coordination number (2SWCN), has been shown to correlate well to the rates of oxidation of different methionine groups in Granulocyte Colony-Stimulating Factor (G-CSF) and in a Human Parathyroid hormone fragment (hPTH(1-34)). Including the dynamics of protein and water molecules in an explicit manner was found to be important for such correlation. Via combined quantum mechanical and molecular mechanical free energy simulations, the activation free energies of the oxidation of methionine residues in G-CSF are found to be equivalent to the values for the oxidation
by Jhih-Wei Chu.
Ph.D.
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Roelofs, Jacobus Johannes Wilhelmu. "Novel statistical modelling approaches for pesticide residues." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/9405/.
Abstract:
Plant protection products play an important role in protecting our food supply against pests, diseases and weeds. As global food demand rises, their role in maintaining the quality and quantity of our food production is likely to increase in the absence of other control methods. To manage the risks associated with pesticide usage, EU laws regulate the placing of plant protection products on the market and the monitoring of pesticide residues in food. This involves assessing the potential risks associated with human dietary exposure by conducting dietary risk assessments which take both consumption patterns and residue levels of pesticides in and on food items into account. Residue levels will vary from one food item to the next so we need to know what the distribution of residues over food items is in order to assess how high residue levels can be. In this thesis we introduce novel statistical approaches that can be used to obtain better estimates of the variation and uncertainty in pesticide residue levels on raw agricultural products. The rst approach uses monitoring data and pesticide usage information to model the correlation in pesticide residue levels when multiple pesticides have been used. Next we introduce an approach that can be used to describe the variation in log-residue levels in units, assuming that multiple data sets share a common shape. The nal model describes both within-eld and between-field variation of residue levels. These new approaches, which provide promising alternatives to existing methods, can be implemented in existing dietary risk assessment software and will expand the suite of models available to risk assessors when assessing dietary exposure to pesticides.
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Jayalatharachchi, Vishakya. "Understanding desilication products in bauxite refinery residues." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/101127/1/Vishakya_Jayalatharachchi_Thesis.pdf.
Abstract:
This research developed standard methods for quantifying and identifying alkali compounds in red mud, with a particular focus on desilication compounds. X-ray diffraction and infrared spectroscopy were used as they are relatively accessible and fast characterisation techniques for industry to use. This research is of particular importance as it will enable better predictions to be made on the suitability/stability of red mud in land rehabilitation programs.
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FARRU, GIANLUIGI. "Valorisation of organic residues through hydrothermal carbonization." Doctoral thesis, Università degli Studi di Cagliari, 2022. http://hdl.handle.net/11584/335549.
Abstract:
Hydrothermal carbonization (HTC) is a thermochemical process which can directly convert wet organic materials producing a carbon-rich solid (hydrochar, HC) and a liquid phase (process water, PW). Hydrochar has chemical and physical properties that make it similar to natural peats and coals. Depending on the process conditions, mostly temperature (180-250°C) and residence time (few hours), this material can be enriched in its carbon content, modifying its structure and providing it interesting characteristics that make it possible to be used for several applications, like energy production, as a soil ameliorant, adsorbent material for different pollutants, and some others reported in literature. In this work, the HTC process was applied to different organic materials such as hemp, grape marc, spent coffee grounds, AD (anaerobic digestion) digestate from hemp, from cow manure, and from agricultural residues, cigarette butts, surgical masks and gloves. Feedstocks and resulting products were physically and chemically characterised to be tested for different applications (e.g., energy production by combustion or AD, soil ameliorant, peat substitute in growing media or fertigation, or to be biologically treated in aerobic wastewater treatment plant). Compared to the feedstocks, hydrochars showed for all the tested materials strong physical and chemical modification (e.g., carbon content increased, and ash reduced). Due to the increased HHV, hydrochar may be used as solid fuel, which entails a higher energy recovery compared to the feedstock. Following HTC, all the tested materials showed a reduced volume (over 70%, in some cases) and an increased density. The possibility to use HC as peat substitute in growing media was tested for cow manure digestate, spent coffee grounds, and grape marc, showing that low amount of HC can partially substitute peat with similar or even better results. However, the addition of higher amount showed inhibition. Pre- and post-treatments tested (extraction, drying, washing) seem to have positive effect on seed germination and plant growth, removing some phytotoxic compounds. However, since these steps can be expensive, further tests should be carried out to understand which compounds cause inhibition, how to remove them or whether it is possible to destroy or avoid producing them by adequately setting the HTC process parameters. Process water (PW) should be properly treated since it contains many different compounds which can become an environmental problem. In this work, the PW valorisation was tested through characterising the liquid. The high amount of nutrient in PW may suggest the use in fertigation; however, germination tests showed inhibition effect. The aerobic treatability was tested through the bioassay on nitrifying bacteria. The high amount of VFAs may make PW a suitable substrate for AD to produce biogas. This work demonstrated that hydrothermal carbonization is a suitable process for the treatment of a wide range of organic materials. Depending on the feedstock, the resulting products may have different properties and characteristics which make them feasible for diverse applications. In general, all the feedstock tested may be used as solid fuel with several advantages, such as higher energy content, reduced volume, possible reduced emission during combustion, ease of dewatering, etc. The use on soil is promising when low amount of HC is used. However, pre- or post-treatments may increase the concentrations. Process water may be biologically treated: anaerobically, to produce biogas and remove some organic compounds and aerobically, but an acclimatation phase may be necessary. HTC proved to be a promising process in the biorefinery concept, especially when integrated with other processes (AD, aerobic degradation, etc.). Materials and energy can be recovered by HTC and re-introduced in the productive cycle and in the market, promoting the circular economy and the zero-waste concept.
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Wentzel, Jeanette Maria. "Die voorkoms van antimikrobiese stowwe in die vleis van uitskot melkkoeie in die Vrystaatstreek en die meegaande kennisvlak van die produsent en verbruikers." Thesis, Bloemfontein : Central University of Technology, Free State, 2006. http://hdl.handle.net/11462/89.
Abstract:
Thesis (M. Tech. ) - Central University of Technology, Free State, 2006Antibiotics have been used on animals since the Second World War for therapeutic purposes. The risks associated with the use of antibiotics in food animals are enormous, due to the possibility of resistance of organisms caused by the usage of low levels of antibiotics. The goals of this study were to determine the prevalence of antibiotic residues in C grade milk cows, and to determine the practices and knowledge of producers regarding the use of antibiotics as well as the knowledge and habits of consumers. In the study the presence of antibiotic residues was tested by means of microbiological inhibition testing. Fifteen percent of all tested samples tested positive for the presence of antibiotic residues. Eleven samples that tested positive on the microbiological inhibition test were sent to the Onderstepoort Veterinary Institute for confirmation. The knowledge of the consumer as well as that of the producer was tested by means of a questionnaire and then processed statistically. Producers were, in general, fairly ignorant regarding the withdrawal period of antibiotic residues. Age and the combination of age and reproduction were the common reasons for the selling of milk cows. Both the sampling and the questionnaires proved that the presence of antibiotic residues is higher than that stated in literature. The selling of the animals was mostly by auction or directly to the abattoirs. Consumer practices regarding the antibiotic residues were mostly in order, although consumers did not have knowledge regarding antibiotic residues. High temperatures, for example in the frying or grilling of meat, will reduce the presence of antibiotic residues because these effects have an influence on the presence of antibiotic residues (Rose et al., 1995). Almost 75% of consumers describe antibiotics in a positive manner. Milk and meat are regarded as posing the greatest risk for the origin of antibiotic residues. A lack of general knowledge regarding antibiotic residues was noteworthy, especially from the consumers of Thaba ’Nchu and Heidedal. The wrong usage of antibiotics by medical practitioners and consumers will certainly have consequences. Most of the consumers (112/227 respondents) indicated that they always completed a course of antibiotics. Forty-nine respondents indicated that they had already used antibiotics and that the therapy was unsuccessful. Antibiotic residues are still present so the risk to the consumer is still viable. Improved sampling and monitoring at abattoirs both for local and export abattoirs is necessary. The “farm to fork” concept and financial incentives by way of subsidies for residue-free products is a positive step. South African consumers are not quality conscious and further studies are necessary to improve the quality and safety of meat.
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Illergård, Kristoffer, Anni Kauko, and Arne Elofsson. "Why are polar residues within the membrane core evolutionary conserved?" Stockholms universitet, Institutionen för biokemi och biofysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-68378.
Abstract:
Here, we present a study of polar residues within the membrane core of alpha-helical membrane proteins. As expected, polar residues are less frequent in the membrane than expected. Further, most of these residues are buried within the interior of the protein and are only rarely exposed to lipids. However, the polar groups often border internal water filled cavities, even if the rest of the sidechain is buried. A survey of their functional roles in known structures showed that the polar residues are often directly involved in binding of small compounds, especially in channels and transporters, but other functions including proton transfer, catalysis, and selectivity have also been attributed to these proteins. Among the polar residues histidines often interact with prosthetic groups in photosynthetic-and oxidoreductase-related proteins, whereas pro-lines often are required for conformational changes of the proteins. Indeed, the polar residues in the membrane core are more conserved than other residues in the core, as well as more conserved than polar residues outside the membrane. The reason is twofold; they are often (i) buried in the interior of the protein and (ii) directly involved in the function of the proteins. Finally, a method to identify which polar residues are present within the membrane core directly from protein sequences was developed. Applying the method to the set of all human membrane proteins the prediction indicates that polar residues were most frequent among active transporter proteins and GPCRs, whereas infrequent in families with few transmembrane regions, such as non-GPCR receptors. Proteins 2011; 79: 79-91.authorCount :3
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Khesin, Boris, Alexei Rosly, and rosly@heron itep ru. "Polar Homology." ESI preprints, 2000. ftp://ftp.esi.ac.at/pub/Preprints/esi941.ps.
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Karpouzas, Dimitrios. "Aspects of the enhanced bio-degradation of Carbofuran and Ethoprophos in soil." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298757.
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Yue, Junqi. "Destruction of TNT and RDX residues and devices /." View online ; access limited to URI, 2005. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3188852.
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Todorovic, Jelena. "Diffusion tests for assessing leaching from incineration residues." Licentiate thesis, Luleå, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26593.
Abstract:
Increasing amounts of incineration residues need to be disposed, reused or treated, which calls for reliable characterisation methods. Leaching tests are often used for an assessment of release of pollutants from wastes under a variety of leaching factors. Nevertheless, the prediction of the contaminants release in field is difficult due to the complexity of the processes occurring in field. This work aims at evaluating limitations and possibilities of making long- term leaching predictions for incineration residues using diffusion leaching tests. Also the effect of carbonation on the leaching of elements was evaluated. Leaching predictions for Cl and Pb based on diffusion test data were compared with leachate data from MSWI bottom ash reused in road construction as well as leachate data obtained using a two-step compliance test. For the first years, leaching of Cl from bottom ash in field could be predicted with an accuracy within one order of magnitude. This could be considered as a good fit. Good agreement was also found between leaching predictions based on the diffusion test and the compliance test for Pb. However, predictions based on a diffusion tests might be misleading for longer time periods as the stock of contaminants depletes. Longer time series of field data are needed for comparison. Field conditions such as wet/dry and freezing/thawing cycles were not considered in this work, but might affect the mobility of contaminants. The impact of such field factors deserves a thorough examination in future research. Carbonation was found to significantly affect leaching of some elements from MSWI bottom ash. Leaching of Pb and Zn was increased due to carbonation, while leaching of Cr, Mo, and Sb decreased. Leaching of Cu was increased by carbonation alone, but it was also observed that leaching could be decreased if carbonation is combined with water-solidification. With such effect on leaching it is necessary to take carbonation into account when leaching predictions are made.Godkänd; 2004; 20070127 (ysko)
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Al-Salihi, Avin. "Close proximity recycling methodology for metal-containing residues." Thesis, Brunel University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445932.
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Ward, Tim. "Metal recovery from medium temperature pressure leach residues." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54982.
Abstract:
Residues of the CESL Cu and Vale Ni sulphide medium temperature pressure leach contain elevated levels of the interest Cu and Ni metals. Metal losses are disproportionately found within a poorly formed amorphous and semi-crystalline iron oxide phase analogous to ferrihydrite. This phase results from incomplete ferric hydrolysis and precipitation that occurs simultaneously with the leaching of the sulphide minerals. An investigation was conducted by ageing the residues at 95°C in water to assess the extraction of lost Cu and Ni and the transformation of ferrihydrite to the more crystalline goethite and hematite species. It was found that 22% of the Cu could be removed from the CESL residue in 24 hours. Repeated ageing was only capable of extracting 38% of the Cu. Extractions of 22% of the Ni and 6% of the Cu were achieved in 24 hours from the Vale residue. Recovery of the lost Cu and Ni was mainly attributed to the washing of entrained and adsorbed Cu and Ni sulphates evenly distributed throughout the residues. A small amount of Cu and Ni was gained from ferrihydrite dissolution during the ageing process. Further investigations by SEM-EDS revealed the presence of unleached Cu and Ni sulphides that also contribute notable metal losses. EMP analysis showed that all hematite precipitated in the Vale residue contained Cu, Ni and SO₄²−. The average hematite particle consisted of 66.1% Fe, 0.85% Ni, 0.73% Cu and 1.19% SO₄²− for an equivalent of 30% Ni and 25% Cu losses to the residue. QXRD analysis of the aged residue showed little evidence of ferrihydrite transformation though ageing stabilised the residues by reducing the amount of X-ray amorphous material present. Improved stability was confirmed by a reduction in mass loss following treatment by a sequential extraction procedure utilising acidified hydroxylamine hydrochloride. This treatment dissolves the ferrihydrite present in the residues and is used as a proxy to assess residue stability and losses of Cu and Ni to the non-crystalline iron oxide phase.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Todorović, Jelena. "Diffusion tests for assessing leaching from incineration residues /." Luleå, 2004. http://epubl.luth.se/1402-1757/2004/14.
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Li, Xiaomin. "Accelerated carbonation of municipal solid waste incineration residues." Thesis, University of Greenwich, 2008. http://gala.gre.ac.uk/8399/.
Abstract:
Incineration can reduce the mass and volume of municipal waste significantly but produces solid waste in the form of bottom ash and air pollution control (APC) residues. Landfill is currently the most commonly used disposal option for these ash residues, however, the impact of hazardous compounds in these wastes on the environment during landfilling is becoming more widely appreciated and cheaper, alternative, management options need to be explored. In this research, the treatment of these municipal solid waste incinerator (MSWI) residues by accelerated carbonation is investigated and compared with naturally aged ashes. Both bottom ash and APC residues were carbonated in an atmosphere composed of gaseous CO2. It was found that the carbonation of calcium oxides/hydroxides resulted in the rapid formation of calcium carbonate and that silicate compounds were hydrated. The reduction of pH from 12-12.5 to 7-9 observed upon carbonation was associated with a reduction in availability of soluble salts and meals. Carbonated ash had a higher buffering capacity to acid attack when compared to the untreated, non-carbonated, ash. The bottom and APC ashes sequestrated between 6% and 13% CO2 (w/w dry weight), respectively upon carbonation; and this may be important where the reduction of greenhouse emissions to the atmosphere is concerned.
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Heron, Carol P. "The analysis of organic residues from archaelogical ceramics." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254610.
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Yau, Sze Tai. "Electrochemical recovery of copper from waste catalyst residues." Thesis, University of Huddersfield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327142.
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Craig, S. "Critical residues in the folding of beta-lactamase." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374750.
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Robinson, Tim. "Solid state fermentation of dye-adsorbed agricultural residues." Thesis, University of Ulster, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274061.
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Phelane, Lisebo. "Polysulfone nanocomposites for electrochemical screening of antibiotic residues." University of the Western Cape, 2017. http://hdl.handle.net/11394/6134.
Abstract:
Philosophiae Doctor - PhD (Chemistry)Antibiotics are defined as any class of organic molecule that kills or inhibits microbes by specific interactions with bacterial targets. Antibiotics may be classified based on bacterial spectrum (broad versus narrow), route of administration, type of activity (bactericidal versus bacteriostatic), and origin (natural versus synthesized), and can also be classified based on their chemical structure. The intensive use of antibiotics for human (domestic and hospital use), veterinary and agriculture purposes, these compounds are continuously released into the environment from anthropogenic sources, such as wastewater treatment plants which are considered as one of the major source of evolution and spreading of antibiotic resistance into the environment.
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Danje, Stephen. "Fast pyrolysis of corn residues for energy production." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17822.
Abstract:
Thesis (MScEng)--Stellenbosch University, 2011.ENGLISH ABSTRACT: Increasing oil prices along with the climate change threat have forced governments, society and the energy sector to consider alternative fuels. Biofuel presents itself as a suitable replacement and has received much attention over recent years. Thermochemical conversion processes such as pyrolysis is a topic of interest for conversion of cheap agricultural wastes into clean energy and valuable products. Fast pyrolysis of biomass is one of the promising technologies for converting biomass into liquid fuels and regarded as a promising feedstock to replace petroleum fuels. Corn residues, corn cob and corn stover, are some of the largest agricultural waste types in South Africa amounting to 8 900 thousand metric tonnes annually (1.7% of world corn production) (Nation Master, 2005). This study looked at the pyrolysis kinetics, the characterisation and quality of by-products from fast pyrolysis of the corn residues and the upgrading of bio-oil. The first objective was to characterise the physical and chemical properties of corn residues in order to determine the suitability of these feedstocks for pyrolytic purposes. Secondly, a study was carried out to obtain the reaction kinetic information and to characterise the behaviour of corn residues during thermal decomposition. The knowledge of biomass pyrolysis kinetics is of importance in the design and optimisation of pyrolytic reactors. Fast pyrolysis experiments were carried out in 2 different reactors: a Lurgi twin screw reactor and a bubbling fluidised bed reactor. The product yields and quality were compared for different types of reactors and biomasses. Finally, a preliminary study on the upgrading of bio-oil to remove the excess water and organics inorder to improve the quality of this liquid fuel was performed. Corn residues biomass are potential thermochemical feedstocks, with the following properties (carbon 50.2 wt. %, hydrogen 5.9 wt. % and Higher heating value 19.14 MJ/kg) for corn cob and (carbon 48.9 wt. %, hydrogen 6.01 wt. % and Higher heating value 18.06 MJ/kg) for corn stover. Corn cobs and corn stover contained very low amounts of nitrogen (0.41-0.57 wt. %) and sulphur (0.03-0.05 wt. %) compared with coal (nitrogen 0.8-1.9 wt. % and sulphur 0.7-1.2 wt. %), making them emit less sulphur oxides than when burning fossil fuels. The corn residues showed three distinct stages in the thermal decomposition process, with peak temperature of pyrolysis shifting to a higher value as the heating rate increased. The activation energies (E) for corn residues, obtained by the application of an iso-conversional method from thermogravimetric tests were in the range of 220 to 270 kJ/mol. The products obtained from fast pyrolysis of corn residues were bio-oil, biochar, water and gas. Higher bio-oil yields were produced from fast pyrolysis of corn residues in a bubbling fluidised bed reactor (47.8 to 51.2 wt. %, dry ash-free) than in a Lurgi twin screw reactor (35.5 to 37 wt. %, dry ash-free). Corn cobs produced higher bio-oil yields than corn stover in both types of reactors. At the optimised operating temperature of 500-530 °C, higher biochar yields were obtained from corn stover than corn cobs in both types of reactors. There were no major differences in the chemical and physical properties of bio-oil produced from the two types of reactors. The biochar properties showed some variation in heating values, carbon content and ash content for the different biomasses. The fast pyrolysis of corn residues produced energy products, bio-oil (Higher heating value = 18.7-25.3 MJ/kg) and biochar (Higher heating value = 19.8-29.3 MJ/kg) comparable with coal (Higher heating value = 16.2-25.9 MJ/kg). The bio-oils produced had some undesirable properties for its application such as acidic (pH 3.8 to 4.3) and high water content (21.3 to 30.5 wt. %). The bio-oil upgrading method (evaporation) increased the heating value and viscosity by removal of light hydrocarbons and water. The corn residues biochar produced had a BET Brynauer-Emmet-Teller (BET) surface area of 96.7 to 158.8 m2/g making it suitable for upgrading for the manufacture of adsorbents. The gas products from fast pyrolysis were analysed by gas chromatography (GC) as CO2, CO, H2, CH4, C2H4, C2H6, C3H8 and C5+ hydrocarbons. The gases had CO2 and CO of more than 80% (v/V) and low heating values (8.82-8.86 MJ/kg).
AFRIKAANSE OPSOMMING: Die styging in olie pryse asook dreigende klimaatsveranderinge het daartoe gelei dat regerings, die samelewing asook die energie sektor alternatiewe energiebronne oorweeg. Biobrandstof as alternatiewe energiebron het in die afgope paar jaar redelik aftrek gekry. Termochemiese omskakelingsprosesse soos pirolise word oorweeg vir die omskakeling van goedkoop landbou afval na groen energie en waardevolle produkte. Snel piroliese van biomassa is een van die mees belowende tegnologië vir die omskakeling van biomassa na vloeibare brandstof en word tans gereken as ’n belowende kandidaat om petroleum brandstof te vervang. Mielieafval, stronke en strooi vorm ’n reuse deel van die Suid Afrikaanse landbou afval. Ongeveer 8900 duisend metrieke ton afval word jaarliks geproduseer wat optel na ongeveer 1.7% van die wêreld se mielie produksie uitmaak (Nation Master, 2005). Hierdie studie het gekk na die kinetika van piroliese, die karakterisering en kwaliteit van by-produkte van snel piroliese afkomstig van mielie-afval asook die opgradering van biobrandstof. Die eerste mikpunt was om die fisiese en chemiese karakteristieke van mielie-afval te bepaal om sodoende die geskiktheid van hierdie afval vir die gebruik tydens piroliese te bepaal. Tweendens is ’n kinetiese studie onderneem om reaksie parameters te bepaal asook die gedrag tydens termiese ontbinding waar te neem. Kennis van die piroliese kinetika van biomassa is van belang juis tydens die ontwerp en optimering van piroliese reaktore. Snel piroliese ekspermente is uitgevoer met behulp van twee verskillende reaktore: ’n Lurgi twee skroef reaktor en ’n borrelende gefluidiseerde-bed reaktor. Die produk opbrengs en kwaliteit is vergelyk. Eindelik is ’n voorlopige studie oor die opgradering van bio-olie uitgevoer deur te kyk na die verwydering van oortollige water en organiese materiaal om die kwaliteit van hierdie vloeibare brandstof te verbeter. Biomassa afkomstig van mielie-afval is ’n potensiële termochemiese voerbron met die volgende kenmerke: mielie stronke- (C - 50.21 massa %, H – 5.9 massa %, HHV – 19.14 MJ/kg); mielie strooi – (C – 48.9 massa %, H – 6.01 massa %, HHV – 18.06 MJ/kg). Beide van hierdie materiale bevat lae hoeveelhede N (0.41-0.57 massa %) and S (0.03-0.05 massa %) in vergelyking met steenkool N (0.8-1.9 massa %) and S (0.7-1.2 massa %). Dit beteken dat hieride bronne van biomassa laer konsentrasies van swael oksiedes vrystel in vergelyking met fossielbrandstowwe. Drie kenmerkende stadia is waargeneem tydens die termiese afbraak van mielie-afval, met die temperatuur piek van piroliese wat skuif na ’n hoër temperatuur soos die verhittingswaarde toeneem. Die waargenome aktiveringsenergie (E) van mielie-afval bereken met behulp van die iso-omskakelings metode van TGA toetse was in die bestek: 220 tot 270 kJ/mol. Die produkte verkry deur Snel Piroliese van mielie-afval was bio-olie, bio-kool en gas. ’n Hoër opbrengs van bio-olie is behaal tydens Snel Piroliese van mielie-afval in die borrelende gefluidiseerde-bed reakctor (47.8 na 51.2 massa %, droog as-vry) in vergelyking met die Lurgi twee skroef reakctor (35.5 na 37 massa %, droog as-vry). Mielie stronke sorg vir ’n hoër opbrengs van bio-olie as mielie strooi in beide reaktore. By die optimum bedryfskondisies is daar in beide reaktor ’n hoër bio-kool opbrengs verkry van mielie stingels teenoor mielie stronke. Geen aansienlike verskille is gevind in die chemise en fisiese kenmerke van van die bio-olie wat geproduseer is in die twee reaktore nie. Daar is wel variasie getoon in die bio-kool kenmerkte van die verskillende Snel Piroliese prosesse. Snel piroliese van mielie-afval lewer energie produkte, bio-olie (HVW = 18.7-25.3MJ/kg) en bio-kool (HVW = 19.8-29.3 MJ/kg) vergelykbaar met steenkool (HVW = 16.2-25.9 MJ/kg). Die bio-olies geproduseer het sommige ongewenste kenmerke getoon byvoorbeeld suurheid (pH 3.8-4.3) asook hoë water inhoud (21.3 – 30.5 massa %). Die metode (indamping) wat gebruik is vir die opgradering van bio-olie het gelei tot die verbetering van die verhittingswaarde asook die toename in viskositeit deur die verwydering van ligte koolwaterstowwe en water. Die mielie-afval bio-kool toon ’n BET (Brunauer-Emmet-Teller) oppervlakte area van 96.7-158.8 m2/g wat dit toepaslik maak as grondstof vir absorbante. The gas geproduseer tydens Snel Piroliese is geanaliseer met behulp van gas chromotografie (GC) as CO2, CO, H2, CH4, C2H4, C2H6, C3H8 and C5+ koolwaterstowwe. Die vlak van CO2 en CO het 80% (v/V) oorskry en met lae verhittingswaardes (8.82-8.86 MJ/kg).