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Tomi, Kenichi. "Relationships between aroma component composition of herbs and its aromachology effects". Kyoto University, 2016. http://hdl.handle.net/2433/215986.
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Kyoto University (京都大学)0048
新制・論文博士
博士(農学)
乙第13034号
論農博第2835号
新制||農||1044(附属図書館)
学位論文||H28||N5007(農学部図書室)
32992
京都大学大学院農学研究科農学専攻
(主査)教授 坪山 直生, 教授 黒木 裕士, 教授 妻木 範行
学位規則第4条第2項該当
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Barnard, Carla. "Investigating the effect of various film-forming polymers on the evaporation rate of a volatile component in a cosmetic formulation". Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1498.
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The topical application of many substances, including drugs, enzymes, moisturizers and fragrances, contributes largely to the cosmetic and pharmaceutical industries. These components are often volatile in nature and dissipate in a matter of hours. When considering the different types of slow release systems, an overwhelming variety of these systems is available. Each one of the systems is unique in a way, and is designed to perform a particular function, whether it facilitates the controlled release of an active into the body via the skin surface (transdermal delivery) or whether it reduces the rate of loss of an active from the skin surface to the surrounding environment. For the purpose of this study, a previously existing fixative formulation which is believed to reduce the rate of loss of an active component to the environment, through film formation on the skin surface, was investigated. Alternative ingredients or components were incorporated together with the original fixative formulation ingredients into an experimental design which investigates the effect of each group of the components present. 18 formulations with various concentrations of the components within the groups and specified upper and lower limits for each component were formulated. The fixative properties of the formulations were analysed through the incorporation of a fixed amount of a simple fragrance molecule, 4- methoxybenzaldehyde, into each formulation and evaporation studies were conducted in an environmental room at 28±1° C over a period of 5 hours followed by gas chromatography analysis and finally data analyses using statistical methods. The most efficient fixative formulation was established using regression analysis. The fragrance compound in this formulation was found to evaporate at a rate of 0.47 g/L per hour. The least efficient fixative formulation lead to the loss of 0.78 g/L of the fragrance component per hour. From the calculated fragrance concentrations, the rate constant for each individual fixative formulation could be calculated and response surface 8 modelling by backward regression was used in order to determine how each component contributes to the rate of loss of the fragrance compound. Since the sum of the original ingredient and its alternative was constant, each of the original ingredients was coupled directly to its alternative and no conclusion could be made about the contribution of individual components. By increasing the concentration of Hydroxypropylcellulose (HPC) 100K and its alternative HPC 140K, while keeping the effects of the other components constant, a decrease in the rate of fragrance loss was observed. The same conclusion could be made when increasing the concentrations of PEG-12 Dimethicone and its alternative cetyl dimethicone (decreases the evaporation rate). An interaction took place between HPC 100K and PEG-12 dimethicone and their alternatives. The negative effect was, however, not as strong as the combined positive effect on the rate of fragrance loss of the individual components HPC and PEG-12 dimethicone. Evidence suggested that the removal of the components polyvinylpyrrolidone and its alternative, polyurethane-32 (Baycusan® C1003), would improve the effectiveness of the fixative formulation in terms of its slow release properties. A confirmation experiment established that the exclusion of these components from the fixative formulation does improve the “slow release” properties thereof. A larger, more intricate design is required to investigate the effect of each one of the individual components and where the sum of the components (original and its alternative) is not constant.
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Nahan, Keaton. "Principal Component Analysis Approach for Determination of Stroke Protein Biomarkers and Modified Atmospheric Pressure Chemical Ionization Source Development for Volatile Analyses". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491817651627161.
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Brito, Givanilton. "Tipificação de méis do estado de Sergipe através do perfil químico dos compostos voláteis obtidos por headspace dinâmico seguido por cromatografia em fase gasosa acoplada a espectrometria de massas (CG/EM)". Universidade Federal de Sergipe, 2012. https://ri.ufs.br/handle/riufs/6037.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorAmong the products of the hive, honey is considered the principal, standing out as natural food and for having multiple pharmacological applications. Honey can be produced by honey bees (Apis mellifera, L.) from the nectar, fruit, plant secretions and excretions of aphids or other sweetened solutions.Their nutritive power, pharmacologic and commercial value depends on its botanical origin, which can be obtained through classical methods as sensory evaluation, physicochemical analyses or melissopalynology. Although, these methods require much experience of the analyst and are costly.In view of the current difficulties in conducting these analyses, methods based on the study of volatile constituents have emerged as an alternative in the search for the source of compound markers of floral honeys. For the identification of these compounds, techniques such as solid in solid phase (SPME) and dynamic headspace (HSD) followed by analysis on gas chromatography coupled to mass spectrometer (GC-MS) are suggested. In this work, different honeyproducing regions in the State of Sergipe were studied, as well as samples of honey originated from other states of Brazil, purchased in local supermarkets. Analyses of volatile components were obtained by dynamic headspace using Porapak Q® and Peat in natura as adsorbent materials. For both, parameters such as amount of sample, salt addition, time and temperature of extractionhave been optimized. Optimization, made possible the identification of 112 different compounds belonging to classes of aliphatic alcohols, aliphatic aldehydes, benzene derivatives, monoterpene hydrocarbons, oxygenated hydrocarbons, norisoprenoids, sesquiterpenes, oxygenated sesquiterpenes, carboxylic acids and others. Among these, a group of senior compounds were studied by principal components analysis and hierarchical cluster analysis. With these analyses was likely to identify the components with biggest weights in the samples and cluster them into five groups with a similarity of 48% based on Euclidean distance. Among the weighty compounds are furfuraldehyde, benzaldehyde, cis-linalool oxide (furanoid), trans-linalool oxide (furanoid), linalool, hotrienol, 4-ketoisoforone, aldehyde lilac (isomer I), cis-linalool oxide (pyranoid) and -terpineol.
Dentre os produtos apícolas o mel é considerado o principal por se destacar como alimento natural e ter várias aplicações farmacológicas, podendo ser produzido por abelhas Apis mellifera a partir do néctar, secreções das plantas e frutos, excreções de afídeos e outras soluções adocicadas. Seu poder nutritivo, farmacológico e valor comercial dependem de sua origem botânica, a qual pode ser obtida através de métodos clássicos como a avaliação sensorial, a melissopalinologia ou análises físico-químicas, porém estes métodos exigem muita experiência do analista e são dispendiosas. Em virtude das dificuldades atuais em realizar essas análises os métodos baseados no estudo dos constituintes voláteis têm surgido como uma alternativa na procura de compostos marcadores da origem floral de méis. Para a identificação destes compostos, técnicas como a microextração em fase sólida (SPME) e headspace dinâmico (HSD) seguido de análise em cromatógrafo em fase gasosa/espectrômetro de massas (CG/EM) são sugeridas. Neste trabalho foram estudados méis de diferentes regiões produtoras do estado de Sergipe, bem como amostras de méis adquiridos em supermercado de Aracaju oriundas de outros estados do Brasil através da análise dos componentes voláteis obtidos por headspace dinâmico utilizando Porapak Q® e Turfa in natura como materiais adsorventes. Para tanto foram otimizados parâmetros como quantidade de amostra, adição de sal, tempo e temperatura de extração. Nas condições otimizadas foi possível identificar 112 diferentes compostos pertencentes às classes dos álcoois alifáticos, benzenóides, aldeídos alifáticos, hidrocarbonetos lineares, monoterpenos, monoterpenos oxigenados, sesquiterpenos, sesquiterpenos oxigenados, norisoprenóides, ácidos carboxílicos e outros. Dentre estes, um grupo de compostos majoritários foram estudados por análise de componentes principais e análise de agrupamento hierárquico. Com estas análises foi possível identificar os componentes de maiores pesos das amostras e agrupá-las em cinco grupos com uma similaridade de 48%, tendo como base a distância Euclidiana. Dentre os compostos de maiores pesos estão o furfural, benzaldeído, cis-óxido de linalol (furanóide), trans-óxido de linalol (furanóide), linalol, hotrienol, 4-ceto-isoforona, lilac aldeído (isômero I), cis-óxido de linalol (piranóide) e o -terpineol.
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Jalal, Ahmed Hasnain. "Multivariate Analysis for the Quantification of Transdermal Volatile Organic Compounds in Humans by Proton Exchange Membrane Fuel Cell System". FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3886.
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In this research, a proton exchange membrane fuel cell (PEMFC) sensor was investigated for specific detection of volatile organic compounds (VOCs) for point-of-care (POC) diagnosis of the physiological conditions of humans. A PEMFC is an electrochemical transducer that converts chemical energy into electrical energy. A Redox reaction takes place at its electrodes whereas the volatile biomolecules (e.g. ethanol) are oxidized at the anode and ambient oxygen is reduced at the cathode. The compounds which were the focus of this investigation were ethanol (C2H5OH) and isoflurane (C3H2ClF5O), but theoretically, the sensor is not limited to only those VOCs given proper calibration.
Detection in biosensing, which needs to be carried out in a controlled system, becomes complex in a multivariate environment. Major limitations of all types of biosensors would include poor selectivity, drifting, overlapping, and degradation of signals. Specific detection of VOCs in multi-dimensional environments is also a challenge in fuel cell sensing. Humidity, temperature, and the presence of other analytes interfere with the functionality of the fuel cell and provide false readings. Hence, accurate and precise quantification of VOC(s) and calibration are the major challenges when using PEMFC biosensor.
To resolve this problem, a statistical model was derived for the calibration of PEMFC employing multivariate analysis, such as the “Principal Component Regression (PCR)” method for the sensing of VOC(s). PCR can correlate larger data sets and provides an accurate fitting between a known and an unknown data set. PCR improves calibration for multivariate conditions as compared to the overlapping signals obtained when using linear (univariate) regression models.
Results show that this biosensor investigated has a 75% accuracy improvement over the commercial alcohol breathalyzer used in this study when detecting ethanol. When detecting isoflurane, this sensor has an average deviation in the steady-state response of ~14.29% from the gold-standard infrared spectroscopy system used in hospital operating theaters.
The significance of this research lies in its versatility in dealing with the existing challenge of the accuracy and precision of the calibration of the PEMFC sensor. Also, this research may improve the diagnosis of several diseases through the detection of concerned biomarkers.
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Hu, Lin Feng. "Chemical analysis studies on the volatile components of Herba Pogostemonis". Thesis, University of Macau, 2005. http://umaclib3.umac.mo/record=b1445816.
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González, Martínez María. "Woody and agricultural biomass torrefaction : experimental study and modelling of solid conversion and volatile species release based on biomass extracted macromolecular components". Thesis, Toulouse, INPT, 2018. http://oatao.univ-toulouse.fr/24326/1/gonzalez_martinez.pdf.
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Nowadays, there is an increasing awareness on the importance of biomass waste as a renewable source of energy, materials and chemicals. In this context, the European project MOBILE FLIP aims at developing and demonstrating mobile conversion processes suitable with variousunderexploited agro- and forest based biomass resources in order to produce energy carriers, materials and chemicals. One of these processes is torrefaction, which consists in a mild thermal treatment, occurring typically between 200 and 300°C during a few tens of minutes in a defaultoxygen atmosphere. The solid product obtained has thermal and processing properties closer to coal, and thus is suitable as fuel for combustion or gasification. During torrefaction, condensable coproducts are released, that may also be source of “green” chemicals. It is therefore crucial to characterize them to optimize the torrefaction process and design industrial units. Up to now, only few works have been focused on characterizing and modelling both solid and condensable species during torrefaction versus operating conditions and feedstock type. Furthermore, these studies typically include a reduced number of biomasses. Cellulose, hemicellulose and lignin,which constitute biomass macromolecular composition, are determining properties to predict biomass behaviour during torrefaction. However, torrefaction tests on these constituents are rare and always based on commercial compounds, which were proved as little representative of the native biomass. The objective of this study is to analyse the influence of biomass characteristics, mainly represented by the macromolecular composition in cellulose, hemicellulose and lignin, on the global behaviour of biomass in torrefaction, both in terms of solid mass loss and of productionprofiles of the volatile species released, in function of the operating conditions.14 biomasses from the main biomass families (deciduouswood, coniferous wood, agricultural byproductsand herbaceous crops) were selected for this study. An optimized extraction procedure was proposed to recover cellulose, hemicellulose and lignin fractions from 5 reference biomasses. Experiments were performed on a thermogravimetric analyzer coupled to a gas chromatography mass spectrometer device through a heated storage loop system (TGA-GC/MS). Solid degradation kinetics and volatile release profiles were followed during torrefaction experiments combining non-isothermal (200 to 300°C at 3°C/min) and isothermal (300°C, 30 min) conditions, ensuring the chemical regime thanks to the appropriate operating conditions. The results obtained with the raw materials demonstrated that biomass macromolecular composition is a main factor influencing biomass behavior in torrefaction. Consequently, the heterogeneity of the resource results in a diverse behavior in torrefaction, particularly in the case of agricultural biomasses. The results with the extracted components evidenced their very different behavior compared to thecommercial compounds, particularly in the case of cellulose. This suggests that a limitation could be induced by the common use in literature of commercial components for torrefaction modelling. The impact on the characterization of macromolecular components was also shown to be prevailing in their behavior in torrefaction, especially in the case of hemicellulose sugar composition and cellulose crystallinity. Furthermore, differences in release kinetics of volatile species during torrefaction were observed, even for volatiles belonging to the same chemical family (acids, furans, ketones). Derived from these results, a torrefaction model based on the additive contribution of extracted cellulose, hemicelluloses and lignin to the global behavior of biomass in torrefaction was proposed, and this for the 5 representative biomasses.
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Tronson, Deidre A., of Western Sydney Hawkesbury University, of Science Technology and Environment College i of Science Food and Horticulture School. "Volatile compounds in some eastern Australian Banksia flowers". THESIS_CSTE_SFH_Tronson_D.xml, 2001. http://handle.uws.edu.au:8081/1959.7/140.
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This project was the very beginning of research into the chemistry of eastern Australian banksia flowers. Using dynamic headspace sampling (DHS) analysis, differences in volatile components, consistent with detection of differences in odour, were detected among three different species and one commercial cultivar. Infraspecific variation was also observed between two known subspecies of Banksia ericifolia and between differently coloured forms of Banksia spinulosa var. collina. The cultivar, Banksia 'Giant Candles', was shown to have some of the chemical components of each of its supposed ancestors. The absence of known wound-response chemicals indicated that this DHS method was successful in leaving the inflorescences undamaged throughout the sampling procedure. The Likens-Nickerson modification of classical hydrodistillation methods was useful. The static headspace method (SHS) was easily automated and was shown to be chemically robust and sufficiently sensitive to detect volatile compounds from only a few flowers. The milder DHS method, which minimised mechanical and heat damage to the plant tissue, produced a different set of results. From the results of this project, a suite of volatile compounds has been proposed that may be useful in future behavioural studies to help determine whether animals are attracted to components of banksia odours. These candidates include some compounds that have been reported in animal secretions, wound-response chemicals that may be produced by the plant to aid its communication with other organisms, and a compound (suggested to be sulfanylmethyl acetate) not previously reported from natural sources. The mildest of the three analytical methods used, dynamic headspace sampling, was shown to be suitable for the potential chemotaxonomic evaluation of some members of the Banksia genus.Doctor of Philosophy (PhD)
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Munch, Ryan Nicholas. "Deodorization of Garlic Breath Volatiles by Food and Food Components". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1383566379.
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Guardiano, Carmelo. "Livelli di pascolo, componenti volatili, antiossidanti e qualità del latte". Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/1018.
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The aim of this study was to evaluate the effect of pasture feeding and cow s breed on milk volatiles fingerprint and to examine the effects of pasture feeding and dairy cattle breed on fat-soluble antioxidant, vitamin content in milk. Four Sicilian dairy farms were selected, two with both Holsteins and Brown Swiss cows and two with only local breed Modicana cows. Bulk milk of each breed per farm was sampled four times per experimental period (spring, summer, and autumn). Samplings within period occurred with weekly intervals. Pasture was available in spring and autumn but not in summer. Spring and autumn differed by botanical composition and plant maturity. During summer cows were grazing stubble. Additional hay and concentrate was supplemented during all periods. Milk samples were analyzed by SMart Nose®: data were statistically evaluated by Principal Component Analysis. Volatiles profiles of samples from spring and autumn compared to summer were discriminated, but not between spring and autumn. There was less variation in volatiles during autumn compared to spring. Milk volatile profiles collected at the last sampling day (spring), except for volatiles composition from Modicana milk, were similar to all samples from summer. At this day, plants were mature and almost dry and chemical composition might have been similar to stubble composition. In all periods, also when pasture was not available during summer, volatiles composition of Modicana milk was different from Holsteins and Brown Swiss milk. Differences during spring and autumn might be explained, at least in part, by the higher average pasture intake of Modicana relative to the Brown Swiss and Holsteins. Pasture benefits relative to vitamin content milk content might be obtained only after a minimum necessary exposure period of cows to pasture. Milks from Modicana had the same levels of beta-carotene of Brown Swiss compared to Holsteins cows, whereas significant higher levels of alfa-tocopherol of Modicana relative to Brown Swiss and Holsteins. As a difference to Holsteins and Brown Swiss cows who had similar feeding regimen, Modicana cows had significant higher pasture intake. Differences in vitamin content contents in milk from Modicana relative to Brown Swiss and Holsteins cows cannot be exclusively explained by breed effects but may mainly be attributed to different levels of pasture intakes.
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Lepore, Marco. "Analisi dei componenti volatili nelle varietà di pesche antiche autoctone del territorio Emiliano-Romagnolo". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022.
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Negli ultimi 50 anni la coltivazione di varietà antiche di pesche a polpa bianca è stata abbandonata per favorire le nuove varietà a polpa gialla, che hanno trovato un maggior apprezzamento da parte dei produttori e dei consumatori. Le motivazioni sono attribuibili in primo luogo ad una maggior facilità di esportazione, e inoltre, dal punto di vista fisiologico le nuove varietà si adattano meglio ai climi caldi, sviluppano frutti di maggiori dimensioni e hanno una maggiore produttività e conservabilità. Lo scopo di questo progetto di tesi è stato quello di analizzare la componente volatile di pesche e nettarine a polpa bianca romagnole, appartenenti a varietà antiche e moderne, in modo da differenziarne il profilo volatile dalle nuove varietà di pesche e, quindi, di valorizzarle. Nelle pesche e nettarine analizzate sono state identificate 23 sostanze aromatiche. Gli aromi che più caratterizzano le varietà antiche di pesche a polpa bianca sono dati da lattoni, terpeni ed esteri, presenti in misura maggiore rispetto alle varietà di nettarine sia a polpa bianca che gialla. Al contrario, aldeidi, chetoni, alcoli ed esteri erano i composti caratterizzanti di quest’ultime. Quindi l’analisi dei composti volatili ha reso prova lampante della ricchezza di biodiversità aromatico-qualitativa che esprimono le varietà antiche.
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Carvalho, Cláudia Yong Dias. "Texturizado de manga. Impacto do processamento na componente do aroma". Master's thesis, ISA, 2014. http://hdl.handle.net/10400.5/6793.
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Mestrado em Engenharia Alimentar - Processamento de Alimentos - Instituto Superior de AgronomiaThe aim of this study was the analysis of volatile compounds responsible for the flavour of a texturized mango product, namely terpenes, lactones, aldehydes and alcohols, evaluating the impact of the processing applied: thermal treatment to inactivate enzymes, texturization with gellan gum, application of an edible coating and two conservation processes. The analytical method used was gas chromatography combined with the technique of solid phase microextraction. The product under development consists in a bar of mango puree texturized using the hydrocolloid gellan gum, matching 1% of the weight of the mango puree. This percentage is composed by gellan low and high acyl, with the ratio 25/75, respectively. The product also has an edible coating, comprised by 1% of gellan gum which is formed with a 90/10 low acyl/high acyl ratio. The thermal treatment to inactivate enzymes of mango puree caused a decrease of most volatile compounds. The texturized mango puree has exhibited an ability to release the volatiles, similar to mango puree. The edible coating applied to the surface of the texturized product showed retention capacity for a small number of volatiles. The applied conservation processes, high hydrostatic pressures and thermal treatments, showed similar effects and didn’t change the volatile profile of the bar significantly. Microbiologically the product proved to be stable and both conservation treatments applied were effective in microbiological control.
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Menifuet, Gankam Adeline. "Estrazione della componente volatile di pesche e nettarine a maturazione completa mediante SPME-GC_MS". Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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L'italia, dopo la Cina è il più grande produttore di pesche. Al giorno d'oggi le pesche e nettarine sono le varietà maggiormente presenti sul mercato e, quindi, anche quelle più studiate. Lo scopo di questo lavoro è quello di studiare la componente volatile di pesche e nettarine sia a polpa gialla che a polpa bianca appartenenti a varietà antiche e nuove per la determinazione della componente volatile è stata utilizzata la tecnica cromatografica GC (gas-cromatografia) accoppiata ad una spettrometro di massa (MS) microestrazione in fase solida (SPME).
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Mirondo, Rita Akinyi. "Contribution of enzymes and other components in food in the formation and destruction of volatile compounds". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1478107372378977.
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Hudson, Davia Tamar. "Variables Affecting the Collection and Preservation of Human Scent Components through Instrumental and Biological Evaluations". FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/201.
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In certain European countries and the United States of America, canines have been successfully used in human scent identification. There is however, limited scientific knowledge on the composition of human scent and the detection mechanism that produces an alert from canines. This lack of information has resulted in successful legal challenges to human scent evidence in the courts of law. The main objective of this research was to utilize science to validate the current practices of using human scent evidence in criminal cases. The goals of this study were to utilize Headspace Solid Phase Micro Extraction Gas Chromatography Mass Spectrometry (HS-SPME-GC/MS) to determine the optimum collection and storage conditions for human scent samples, to investigate whether the amount of DNA deposited upon contact with an object affects the alerts produced by human scent identification canines, and to create a prototype pseudo human scent which could be used for training purposes. Hand odor samples which were collected on different sorbent materials and exposed to various environmental conditions showed that human scent samples should be stored without prolonged exposure to UVA/UVB light to allow minimal changes to the overall scent profile. Various methods of collecting human scent from objects were also investigated and it was determined that passive collection methods yields ten times more VOCs by mass than active collection methods. Through the use of polymerase chain reaction (PCR) no correlation was found between the amount of DNA that was deposited upon contact with an object and the alerts that were produced by human scent identification canines. Preliminary studies conducted to create a prototype pseudo human scent showed that it is possible to produce fractions of a human scent sample which can be presented to the canines to determine whether specific fractions or the entire sample is needed to produce alerts by the human scent identification canines.
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Léal, Françoise. "Etude de la production et de l'émanation de composés volatils malodorants sur textile à usage sportif". Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL070N/document.
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Si la sueur fraîchement émise par le corps humain est inodore, la dégradation de celle-ci par la flore bactérienne cutanée produit des composés volatils malodorants, responsables des odeurs de transpiration. Les odeurs de transpiration apparaissent également sur les vêtements au cours de leur utilisation, particulièrement sur les textiles réalisés en fibres synthétiques. Ce travail a pour but d’améliorer la compréhension du phénomène d’émanation d’odeurs en étudiant l’effet du sujet testé, l’effet de la flore bactérienne et l’effet du textile sur les émissions de composés volatils malodorants.L’intérêt de ce travail réside dans l’approche globale de la problématique des odeurs de transpiration et dans la diversité des méthodes de mesure mises en place, tant dans l’étude de la flore microbiologique que dans les méthodes de mesures des composés odorants émis.Dans un premier temps, le dénombrement simultané de la flore bactérienne sur la peau et sur le vêtement a été réalisé sur un échantillon de 15 sujets à l’issue d’un exercice physique. Cette expérimentation a permis d’évaluer le taux de transfert bactérien moyen lors d’une activité sportive et d’étudier son rôle dans l’émission d’odeurs. Ensuite, afin d’affiner ces résultats, une méthode basée sur la biologie moléculaire a été mise en place pour réaliser le suivi qualitatif de la stabilité de la flore commensale axillaire d’un sujet pendant 3 mois. Le transfert bactérien spécifique entre la peau du testeur et le vêtement a été étudié pour 4 matières textiles sélectionnées (dont le coton et le PET). Ceci a permis de déterminer le rôle du transfert bactérien spécifique dans l’émission des odeurs à partir de textile.Enfin, le dernier chapitre est consacré à l’étude de l’émission de composés volatils et odorants à l’aide de mesures olfactives et d’un nez électronique au cours du temps par 8 composants textiles sélectionnés. Après traitement statistique par analyse en composante principale et étude détaillée des mesures, 9 composés chimiques ont été identifiés comme indicateurs d’un comportement textile malodorant. Ces derniers pourraient être utilisés dans la mise en place d’une méthode ciblée de mesure physico-chimique des mauvaises odeurs.Ce travail a permis de déterminer l’impact de chacun des facteurs sujet, flore bactérienne et textile dans l’émission d’odeurs. En outre, ce travail ouvre des perspectives sur l’étude des contaminations bactériennes par contact, mais également dans l’étude des odeurs, sur les phénomènes de désorption de molécules volatiles à partir de différentes matrices textiles et sur les solutions pouvant être envisagées pour limiter les émissions odorantes à partir de textilesFresh human sweat is odorless. Odoriferous volatile compounds are produced by the metabolism of bacteria living on the skin, generating strong malodor. Sweaty body odors do also appear on clothes during use, and especially on synthetic fabrics. The aim of this document is to improve understanding of odor emission by investigating subject effect, microbiota effect and fabric effect on the emission of odoriferous volatile compounds.Odors of perspiration are hereby globally approached with a wide use of methods and experimental devices, for microbial flora study as well as for odoriferous volatile compounds emission study.First, microflora enumeration has been simultaneously processed on the skin and on the fabric after exercise for 15 subjects. This experiment allowed an evaluation of the average bacterial transfer yield during physical activity and the beginning of the investigation of its effect on odor emission.A molecular biology methodology has then been developed in order to refine these results. Monitoring of qualitative composition of the microbiota has been performed to study the stability of the armpit’s ecosystem on a subject during 3 months. Specific microbial transfer from subject’s skin to clothe has been performed for 4 textile fabrics (including cotton and PET). This leaded to characterize the effect of specific bacterial transfer on odor emission from fabric.The last chapter is dedicated to the study of the emission of odoriferous volatile compounds over time using olfactory measurements and electronic nose for 8 selected fabrics. Principal component analysis targeted 9 chemical compounds that have been selected as malodorous behavior indicators for a given fabric. Those 9 compounds could be used for setting up a fitted physicochemical method of malodor.To conclude, this study helped to understand the effect of 3 factors in odor perception from a fabric after sport : subject, microbial flora and fabric. Perspectives have been charted on contact microbial contamination, but also on odor, and especially on desorption of odoriferous volatile molecules from a textile or knitted matrix. The solutions that could be used to limit malodorous emission from fabrics have also been discussed
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Pommer, Linda. "Oxidation of terpenes in indoor environments : A study of influencing factors". Doctoral thesis, Umeå University, Ecology and Environmental Science, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-29.
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In this thesis the oxidation of monoterpenes by O3 and NO2 and factors that influenced the oxidation were studied. In the environment both ozone (O3) and nitrogen dioxide (NO2) are present as oxidising gases, which causes sampling artefacts when using Tenax TA as an adsorbent to sample organic compounds in the air. A scrubber was developed to remove O3 and NO2 prior to the sampling tube, and artefacts during sampling were minimised when using the scrubber. The main organic compounds sampled in this thesis were two monoterpenes, alfa-pinene and delta-3-carene, due to their presence in both indoor and outdoor air. The recovery of the monoterpenes through the scrubber varied between 75-97% at relative humidities of 15-75%.
The reactions of alfa-pinene and delta-3-carene with O 3, NO2 and nitric oxide (NO) at different relative humidities (RHs) and reaction times were studied in a dark reaction chamber. The experiments were planned and performed according to an experimental design were the factors influencing the reaction (O3, NO2, NO, RH and reaction times) were varied between high and low levels. In the experiments up to 13% of the monoterpenes reacted when O3, NO2, and reaction time were at high levels, and NO, and RH were at low levels. In the evaluation eight and seven factors (including both single and interaction factors) were found to influence the amount of alfa-pinene and delta-3-carene reacted, respectively. The three most influencing factors for both of the monoterpenes were the O 3 level, the reaction time, and the RH. Increased O3 level and reaction time increased the amount of monoterpene reacted, and increased RH decreased the amount reacted.
A theoretical model of the reactions occurring in the reaction chamber was created. The amount of monoterpene reacted at different initial settings of O3, NO2, and NO were calculated, as well as the influence of different reaction pathways, and the concentrations of O3 and NO2, and NO at specific reaction times. The results of the theoretical model were that the reactivity of the gas mixture towards alfa-pinene and delta-3-carene was underestimated. But, the calculated concentrations of O3, NO2, and NO in the theoretical model were found to correspond to a high degree with experimental results performed under similar conditions. The possible associations between organic compounds in indoor air, building variables and the presence of sick building syndrome were studied using principal component analysis. The most complex model was able to separate 71% of the “sick” buildings from the “healthy” buildings. The most important variables that separated the “sick” buildings from the “healthy” buildings were a more frequent occurrence or a higher concentration of compounds with shorter retention times in the “sick” buildings.
The outcome of this thesis could be summarised as follows;
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Grover, Brett D. "Measurement, characterization, and source apportionment of the major chemical components of fine particulate material, including semi-volatile species /". Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd1174.pdf.
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Lv, Guang Ping. "Analysis of volatile components in Cinnamomum cassia using gas chromatography-mass spectrometry and the effect of sample preparation". Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2454987.
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Mostert, Erna. "The effect of Karoo browse and veldt feeding on long-chain and volatile fatty acid components in lamb". Diss., University of Pretoria, 2020. http://hdl.handle.net/2263/73436.
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A uniform group of typical Dorper lambs were obtained from a breeding farm in Upington in the Northern Cape Province of the Republic of South Africa. The sheep were randomly allocated into two groups; one herd was raised on Karoo browse veldt, and the other group grazed Karoo grass veldt. Both groups consisted of 5 ewes and 5 wethers. Lambs were allowed to graze for a period of ninety days at an initial live mass of approximately 27 kg in order to reach an average target live mass of 40 kg.
Fat percentage and subcutaneous fat thickness of lambs did not differ significantly between those from Karoo browse veldt or Karoo grass veldt. Subcutaneous adipose tissue samples from lambs from Karoo grass veldt contained significantly higher molar concentrations of oleic acid (C18:1(n-9) cis) and significantly lower molar concentrations of myristic acid (C14:0) and linoleic acid
(C18:2(n-6)) compared to subcutaneous fat tissue samples from those from Karoo browse veldt.
The subcutaneous fat of lambs from Karoo browse veldt contained higher gravimetric concentrations of lauric acid (C12:0) compared to the subcutaneous fat of lambs reared on Karoo grass veldt. The subcutaneous fat from lambs from Karoo browse veldt displayed marginally higher saturated fatty acid to unsaturated fatty acid ratios compared to subcutaneous adipose tissue samples from those from Karoo grass veldt. Subcutaneous fat samples of lambs from Karoo browse veldt contained
significantly lower concentrations of monounsaturated fatty acids and significantly higher saturated fatty acid concentrations in comparison to the subcutaneous adipose tissue of lambs from Karoo grass veldt (P < 0.05). Subcutaneous fat of lambs from Karoo grass veldt displayed numerically higher cis fatty acid to trans fatty acid ratios.
Interesting differences in longer-chain fatty acids (> C20) were discovered between dietary treatments. Gondoic acid (C20:1) was present at significantly higher gravimetric proportions in the fat of ewes from both Karoo browse veldt and Karoo grass veldt compared to wethers and was significantly higher in adipose tissue samples of animals reared on Karoo grass veldt (P < 0.05). The subcutaneous fat of lambs from Karoo grass veldt contained significantly higher molar proportions of behenic acid (C22:0) compared to the subcutaneous fat samples of lambs from Karoo browse veldt (P < 0.05).
Erucic acid (C22:1(n-9)) was significantly higher in the oesophageal samples obtained from Karoo grass veldt compared to oesophageal samples from lambs that had grazed Karoo browse veldt (P < 0.05). Lignoceric acid (C24:0) was present in oesophageal samples, while it was absent in the samples from subcutaneous adipose tissue. The rate at which one fatty acid is deposited from the diet into subcutaneous adipose tissue compared to the rate at which a fatty acid is synthesized de novo can explain differences in fatty acid metabolism between different diets. The relation between dietary and tissue fatty acids displayed significant interactions between diet and sex for the ratio of C18:3(n-3)/ C16:0 (P < 0.05). Animal fatty acid metabolism did not differ significantly between Karoo browse veldt and Karoo grass veldt in this study (P < 0.05).
The application of comprehensive gas chromatography time of flight mass spectrometry identified 3- methylthio-2-butanone as a potential marker for Karoo lamb in raw meat samples. Caryophyllene was present in three of the five Karoo grass-fed lamb samples. β-Caryophyllene may serve as a biomarker in meat to designate a grass diet (Priolo et al., 2004). Cymene was present in each of the Karoo browse and Karoo grass-fed lamb samples and may serve as a potential marker.Dissertation (MSc)--University of Pretoria, 2020.
Animal and Wildlife Sciences
MSc (Agric)
Unrestricted
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Grover, Brett D. "Measurement, Characterization, and Source Apportionment of the Major Chemical Components of Fine Particulate Material, Including Semi-Volatile Species". BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/359.
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The promulgation of revised standards for atmospheric fine particles (PM2.5) by the US EPA has sparked renewed interest in the ability to accurately measure and characterize suspended atmospheric particulate matter. Semi-volatile material (SVM), consisting of ammonium nitrate and semi-volatile organic material (SVOM), is not accurately measured by EPA accepted methods such as the Federal reference method (FRM) or Tapered Element Oscillating Microbalance (TEOM). However, SVM is often a major fraction of urban aerosols. Recent advances in atmospheric sampling instrumentation allowed for the semi-continuous characterization of urban PM2.5, including SVM. The Filter Dynamic Measurement System (FDMS) was shown to measure total PM2.5 mass including semi-volatile species. Validation of the FDMS was performed by comparison with the particle concentrator-Brigham Young University organic sampling system (PC-BOSS) and the real-time total ambient mass sampler (RAMS). Semi-continuous ambient particulate concentrations of sulfate, nitrate and ammonium ion were measured by a newly developed Dionex instrument which was field tested and validated for the first time in Fresno, CA. Either a modified Sunset Laboratory carbon monitor, collocated with a conventional Sunset carbon monitor employing a common inlet, or the newly developed dual-oven Sunset monitor allowed for the semi-continuous determination of both nonvolatile and semi-volatile organic material. This was the first attempt to characterize both nonvolatile and semi-volatile fractions of an urban aerosol in a semi-continuous manner using all semi-continuous instruments. A suite of instruments for semi-continuous PM2.5 monitoring was recommended including, an R&P FDMS for the measurement of PM2.5 mass, a dual-oven Sunset monitor for the measurement of nonvolatile and semi-volatile carbonaceous species, and a Dionex GP-IC for the measurement of inorganic species. A TEOM monitor is also recommended to measure nonvolatile PM2.5 mass. Using these instruments, semi-continuous mass closure was obtained for the first time during a study conducted in Riverside, CA. The advantage of using semi-continuous sampler data in the application of source apportionment was elucidated. Local aerosols are often impacted by short-term pollution episodes that cannot be temporally resolved using integrated samplers. One-h averaged data applied to source apportionment models was shown to increase the power of the model to predict sources, both primary and secondary, that exhibit diurnal short-term episodes.
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Curran, Allison Marsh. "The analytical determination of the uniqueness and persistence of the volatile components of human scent using optimized collection methods". FIU Digital Commons, 2005. http://digitalcommons.fiu.edu/etd/2697.
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The Locard exchange principle proposes that a person can not enter or leave an area or come in contact with an object, without an exchange of materials. In the case of scent evidence, the suspect leaves his scent in the location of the crime scene itself or on objects found therein. Human scent evidence collected from a crime scene can be evaluated through the use of specially trained canines to determine an association between the evidence and a suspect. To date, there has been limited research as to the volatile organic compounds (VOCs) which comprise human odor and their usefulness in distinguishing among individuals. For the purposes of this research, human scent is defined as the most abundant volatile organic compounds present in the headspace above collected odor samples.
An instrumental .method has been created for the analysis of the VOCs present in human scent, and has been utilized for the optimization of materials used for the collection and storage of human scent evidence. This research project has identified the volatile organic compounds present in the headspace above collected scent samples from different individuals and various regions of the body, with the primary focus involving the armpit area and the palms of the hands. Human scent from the armpit area and palms of an individual sampled over time shows lower variation in the relative peak area ratio of the common compounds present than what is seen across a population. A comparison of the compounds present in human odor for an individual over time, and across a population has been conducted and demonstrates that it is possible to instrumentally differentiate individuals based on the volatile organic compounds above collected odor samples.
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Beswick, Gordon. "An investigation into the volatile components present in selected varieties of frozen raspberry (Rubus idaeus L.) fruit and juice". Thesis, London South Bank University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329395.
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Funk, Claudia [Verfasser], Carsten [Akademischer Betreuer] Münker i Dominik [Akademischer Betreuer] Hezel. "Abundances and distribution of chalcogen volatile elements in chondritic meteorites and their components / Claudia Funk. Gutachter: Carsten Münker ; Dominik Hezel". Köln : Universitäts- und Stadtbibliothek Köln, 2015. http://d-nb.info/1071947052/34.
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Jung, Da-Mi. "Interactions between volatile flavor compounds and food matrix components studied using nuclear magnetic resonance spectroscopic and solid phase microextraction techniques /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Sostaric, Tomislav. "Development of a solid phase micro-extraction-gas chromatographic method for the analysis of volatile components in vanilla extracts and flavourings". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2001. https://ro.ecu.edu.au/theses/1042.
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Vanilla is a very important flavouring agent, it is used as a major ingredient in a number of food products. The taste and aroma results from a specific blend of components present in the extract. There are over 170 volatile components, which all contribute to the flavour of the extract. These volatile components can be present in trace amounts or in relatively high concentrations. The range and concentration of volatile components is somewhat characteristic of the vanilla extract and its origin. Due to the high cost and low availability of natural extract, nature-identical and synthetic flavourings are often used to flavour foods and beverages. As natural extracts are very expensive, compared to nature-identical and synthetic vanilla flavourings, there have been many attempts to adulterate them. There are many different methods available for the characterisation of vanilla extracts. These include high performance liquid chromatography (HPLC), isotope ratio mass spectrometry (IRMS), gas chromatography (GC) and thin layer chromatography. However, traditional methods for the extraction of volatile components from non-volatile components for GC analysis, in particular, are time-consuming and prone to sample loss and degradation. Solid phase micro-extraction (SPME) is a relatively new separation technique, which can be used in conjunction with HPLC or GC. The anolytes can be extracted from a variety of matrices using a fused silica fibre exposed to the headspace of the sample. This provides a simple and effective technique for the selective extraction of volatile and semi-volatile components from a sample containing non-volatile components. A SPME-GC method was developed to extract and analyse a range of natural extracts, nature-identical extracts and synthetic flavourings. Using a polyacrylate (PA) fibre, the volatile components were extracted at room temperature. No sample preparation was required (other than dilution). The SPME-GC method was used to qualitatively and quantitatively analyse a range of extracts and flavourings as well as food products. The method was also successfully compared to an existing HPLC method.
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Ye, Liyun. "Antioxidant Activity of Ampelopsis Grossedentata Crude Extract and its Major Component Dihydromyricetin". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/76833.
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Oxidation limits the shelf life of many food products. Adding antioxidants to foods is the most common way to solve this problem. Reports on safety issues of synthetic food additives have raised consumer interest in "all natural" foods, without added antioxidants or with synthetic replaced with natural antioxidants. The natural antioxidants now in use are much more expensive and less potent than the synthetic antioxidants. Thus, effective and economical natural antioxidants are of great interest to researchers. Teng Cha is a type of herbal tea found in China that has reported high levels of antioxidants. Antioxidant activity of Teng Cha extract and its major component dihydromyricetin has been reported, but no studies have provided clear evidence for the antioxidant effectiveness of Tech Cha extracts. The goal of this study was to measure the antioxidant activity of Teng Cha extract and dihydromyricetin (DHM), a major component of Tech Cha extract. The DPPH assay was conducted and antioxidant activities of the crude extract and dihydromyricetin were evaluated in soybean oil based on the peroxide value, anisidine value, Totox value, headspace volatiles and headspace oxygen. Antioxidant effectiveness was also evaluated in a cooked beef model system. DHM was more potent than BHA in preventing soybean oil oxidation. The crude extract was not as effective as BHA and DHM, possibly because it contained transition metals. In cooked beef, DHM and the crude extract showed lower activity than BHA, possibly due to their low solubility. Overall, Teng Cha extract and DHM are potential natural food antioxidants for future applications.Master of Science in Life Sciences
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Bourchier, Robert S. "Development of traps for adult Glischrochilus quadrisignatus (Say) (Coleoptera:Nitidulidae) and investigation of olfactory responses to volatile components of corn, raspberry and tomato". Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66170.
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Giglio, Daniele. "Caratterizzazione mediante GC/MS della componente aromatica di alcune cultivar "antiche" di pesche bianche emiliane romagnole". Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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L’incessante miglioramento varietale volto ad offrire un prodotto corrispondente alle sempre più dinamiche richieste del mercato e le esigenze di quest’ultimo, hanno determinato l’abbandono di antiche varietà di pesche. Un esempio particolare è quello della pesca a pasta bianca, se pur caratterizzata da un alto grado di succosità ed un aroma delicato, è stata progressivamente sostituita da cultivar a pasta gialla dotate di una maggiore resistenza alle manipolazioni ed ai trasporti, rendendole quindi più vantaggiose nelle operazioni di raccolta e vendita. Negli ultimi anni si è posta l’attenzione alla valorizzazione delle varietà autoctone date le loro caratteristiche organolettiche ma anche per una maggiore adattabilità al territorio e alle avversità biotiche che lo contraddistinguono. Secondo diverse ricerche di mercato, la qualità sensoriale di questo frutto è sancita da tre elementi essenziali: la succosità, il gusto e l’aroma. Si è visto come quest’ultimo sia influenzato da innumerevoli elementi, fra i quali troviamo i fattori pedoclimatici, dalle condizioni colturali adottate, dall’epoca di raccolta ed infine le caratteristiche intrinseche del frutto dettate dalle diversità pomologiche (dovute alle differenze tra la pesca a pasta gialla e quella a pasta bianca). In tale studio si è deciso di analizzare la composizione aromatica di campioni di pesche tenendo in considerazione anche la loro buccia proprio perché una parte di questi composti risiede anche in tale frazione. In particolare ci si è focalizzati sulla quantificazione di 9 composti volatili, già identificati come quelli maggiormente presenti nelle pesche in uno studio precedentemente compiuto: esanale, 2-esanale, (E)-2-esenolo, benzaldeide, o-trienolo, p-menth-1-en-9-al, γ-esalattone, γ-decalattone e δ-decalattone.
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Zhu, Bing. "THE INFLUENCE OF FORMULATION VARIABLES ON PARTICLES GENERATED FROM SOLUTION BASED PRESSURIZED METERED DOSE INHALERS". Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/9758.
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The main aims of this work were to investigate the aerosol performance, particle formation process and physico-chemical properties of particles produced from solution-based pressurized metered dose inhalers (pMDIs) formulated with different co-solvent concentrations. In addition, the influences of different active pharmaceutical compounds and glycerol as the non-volatile components were also evaluated. This thesis demonstrated the complex nature of particle formation in solution based pMDIs and investigated the influence of co-solvent (e.g. ethanol) and non-volatile additives (e.g. glycerol and drug type) on aerosol performance, particle maturation, morphology and the physico-chemical properties of the final ‘deposited’ drug system. Significant differences in all the above factors were observed when these variables were altered and the properties could be related to the mechanisms of aerosol generation and the nature of the additives. Ultimately, this enhanced the knowledge in the field that may be used when developing new solution based pMDI systems.
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Chaves, André Luiz de Oliveira. "Sustentabilidade na arquitetura e o estudo dos compostos orgânicos voláteis emitidos por componentes vinílicos em habitações". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/102/102131/tde-13102016-112832/.
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Nas últimas décadas, o policloreto de vinila (PVC) tem sido cada vez mais utilizado na Construção Civil, em razão de suas propriedades que o condiciona a substituir outros materiais na execução das obras. Neste caso, tais propriedades são conferidas pela ação de aditivos incorporados na formulação deste polímero, que o torna capaz de ser utilizado em diferentes aplicações, sendo uma delas os revestimentos vinílicos para o recobrimento de superfícies no interior dos edifícios. Entretanto, em pesquisas internacionais, ocorridas a partir dos anos 1990, ficou comprovado que havia a presença de substâncias químicas, denominadas compostos orgânicos voláteis (COV), nestes revestimentos. Diante destes fatores, na presente pesquisa, propôs-se a identificação e quantificação destas substâncias químicas em revestimentos vinílicos para aplicação em pisos e paredes, e nos adesivos de contato (colas), por meio de técnicas analíticas: micro-extração de fase sólida e cromatografia gasosa acoplada a espectrômetro de massas e termogravimetria acoplada ao espectroscópio de infravermelho. Os resultados das análises qualitativas indicaram a presença de compostos pertencentes às classes químicas dos ésteres, éter glicólicos, alcanos, álcoois, cetonas, antioxidantes, ésteres de acetato, terpenos, tióis, organoclorados, solventes hidrocarbonetos e ácido cloreto, encontrados em sua maior parte nas amostras de linhas de piso vinílico e de adesivo de contato, pertencentes à uma das empresas líderes de mercado. Enquanto que as amostras de revestimentos vinílicos de parede não indicaram a presença de COV. Os resultados mais significativos nas análises quantitativas foram obtidos com as amostras de revestimentos, aplicados com adesivo de contato (cola), que indicaram concentrações de 216,41 mg/m³ e de 403,33 mg/m³ do composto 2-etil-1-hexanol, cujos valores estavam acima do limite máximo de 110 mg/m³ estipulado pela norma internacional MAK. Este e outros COVs identificados nesta pesquisa foram analisados quanto aos efeitos que podem causar na saúde humana, se ultrapassarem os limites máximos estabelecidos pelas normas internacionais, que vão desde os efeitos agudos, como irritações de pele, membranas mucosas dos olhos, nariz, garganta e trato respiratório, aos efeitos graves, como doenças neurológicas, distúrbios no ritmo cardíaco, depressão do sistema nervoso, asfixia e câncer. Além de ser verificado se os compostos orgânicos identificados podem contribuir para a redução da qualidade do ar interno das habitações.In recent decades, the polyvinyl chloride has been increasingly used in civil construction, because of its properties that giving them conditions to replace other materials in the works of buildings. In this case, these properties are conferred by the incorporated additives in the formulation of the polymer, which makes it able to be used in different applications, being part of them the vinyl coverings, inside buildings. However, in international research that took place from the 1990s, it was proved that existed chemicals called volatile organic compounds (VOCs) in these coatings. Given these factors, in the present study aimed to identify and quantify these chemicals in vinyl coatings for use on floors and walls, and contact adhesives (glues), by means of analytical techniques: phase micro-extraction and solid gas chromatography coupled to mass spectrometry and thermogravimetry coupled with infrared spectroscopy. In this case, the additives are incorporated into the formulation of this polymer gives it properties which make it able to be used in different applications, as is the case of vinyl floorings and the vinyl wallpapers, which feature flexible and semi-flexible behavior, due to presence of plasticizers (phthalates) in their formulations. The results of the qualitative analysis showed the presence of compounds belonging to the chemical classes of esters, glycol ether, alkanes, alcohols, ketones, antioxidants, acetate esters, terpenes, thiols, chlorinated, hydrocarbon solvents and acid chloride, found mostly in samples of floor lines and vinyl contact adhesive, both sold in Brazil. While samples of vinyl wall coverings do not indicate the presence of VOC. The most significant results was obtained in quantitative analysis with samples of coatings applied with contact adhesive (glue), which indicated concentrations of 216.41 mg / m³ and 403.33 mg / m³ of the 2-ethyl-1-hexanol compound, whose values were above the upper limit of 110 mg / m³ stipulated by international standard MAK. This and other VOCs identified in this study were analyzed about the effects that can cause human health, if they exceed the limits set by international standards, ranging from the acute effects such as skin irritation, mucous membranes of the eyes, nose, throat and respiratory tract, to the chronic effects such as neurological disorders, heart rhythm disorders, nervous system depression, asphyxia and cancer. In addition to it is verified if the identified organic compounds may contribute to the reduction of the indoor air quality of the houses.
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CÃndido, Cinthya Soares. "Estudo da atividade in vitro de componentes da dieta e de plantas medicinais do Nordeste Brasileiro sobre Helicobacter Pylori". Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1221.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoHelicobacter pylori à uma bactÃria que infecta cerca de 50% da populaÃÃo mundial constituindo um dos principais fatores de risco para o desenvolvimento de cÃncer gÃstrico. O aparecimento deste tipo de cÃncer està associado à presenÃa da bactÃria e a uma soma de elementos de risco, tais como os hÃbitos alimentares, a predisposiÃÃo genÃtica e fatores ambientais. O presente trabalho teve como objetivo avaliar o efeito de componentes da dieta nordestina (sal, vinagre, pimenta e sumo de batata), extratos e Ãleos essenciais no crescimento de H. pylori. No estudo foram utilizadas uma cepa padrÃo e uma clÃnica. O mÃtodo escolhido para a realizaÃÃo da triagem foi o teste da zona de inibiÃÃo e para determinaÃÃo da ConcentraÃÃo InibitÃria MÃnima (CIM) foi o de diluiÃÃo em Ãgar descrito pelo CLSI. As cepas foram inoculadas em meio de cultura apropriado contendo diferentes concentraÃÃes das substÃncias testadas. A leitura foi determinada macroscopicamente e o crescimento confirmado atravÃs da realizaÃÃo da microscopia pelo mÃtodo de Gram e provas bioquÃmicas. Foi verificado que o sal nÃo inibiu o crescimento de H. pylori e nem alterou a sua morfologia, contudo, foi capaz de influenciar na aÃÃo de um antimicrobiano, in vitro. O vinagre e a pimenta nÃo apresentaram aÃÃo antimicrobiana. O sumo de batata foi capaz de promover o crescimento bacteriano mesmo que em pequena proporÃÃo. Os extratos etanÃlicos de erva-cidreira (Lippia alba Mill. N.E.B quimiotipos I, II, III) e macela (Egletes viscosa L.) foram ativos contra a bactÃria. Os Ãleos essenciais de alfavaca verde (Ocimum gratissimum L.) e roxa (Ocimum sp), aroeira (Myracrodruom urundeuva All.), erva-cidreira (L. alba Mill. N.E.B quimiotipos I, II, III) e macela (E. viscosa L.) tambÃm foram ativos contra H. pylori. A caracterizaÃÃo quÃmica confirmou os constituintes majoritÃrios das plantas. H. pylori constitui, hoje, uma vasta fonte de pesquisa em diversos campos investigativos. Estudos de transmissÃo, prevalÃncia, resistÃncia a drogas antimicrobianas, novas alternativas terapÃuticas e desenvolvimento de vacinas sÃo necessÃrios e bastantes promissores.
Helicobacter pylori is a bacteria that infects about 50% of the world population constituting one of the principal risk factors for the development of gastric cancer. The emergence of this cancer type is associated to the presence of the bacteria and risk elements, such as the alimentary habits, the genetic predisposition and environmental factors. The present work had as objective evaluates the effect of components of the Northeastern diet (salt, vinegar, pepper and potato juice), extracts and essential oils on H. pylori growth. In the study a reference and a clinic strain were used. The chosen method for the accomplishment of the screening test was the inhibitory-zone testing and for determination of the Minimum Inhibitory Concentrations (MIC) it was used the agar dilution method as described by Clinical and Laboratory Standards Institute (CLSI). The strains were inoculated in appropriate culture medium containing different concentrations of the tested substances. The reading was determined macroscopically and the growth confirmed through the accomplishment of the microscopy by the Gram method and biochemical tests. It was verified that the salt did not inhibit the growth and morphology of H. pylori, however, it was able to influence the antimicrobial effect, in vitro. The vinegar and the pepper did not show antimicrobial activity. The potato juice was shown to promote the bacterial growth. The ethanolic extracts of Lippia alba Mill. N.E.B chemotypes I, II, III) and Egletes viscosa L. were active against the bacteria. The essential oils of Ocimum gratissimum L., Ocimum sp, Myracrodruom urundeuva All., L. alba Mill. N.E.B chemotypes I, II, III and E. viscosa L. were also active against H. pylori. The chemical characterization confirmed the majority constituents of the plants. H. pylori constitute, today, a vast research source in several areas. Related studies the transmission prevalence, resistance antimicrobial, new therapeutic alternatives and development of vaccines they are necessary and plenty promising.
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Sousa, Regina Furtado Rodrigues Pereira. "Componentes das aguardentes de cana-de-aÃÃcar de Cabo Verde e do Nordeste Brasileiro: uma anÃlise comparativa". Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6440.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoEste trabalho teve como objetivo desenvolver/adaptar e validar metodologias analÃticas para identificaÃÃo e quantificaÃÃo dos congÃneres mais relevantes para a qualidade das aguardentes de cana de aÃÃcar artesanais e industriais produzidas em algumas Ilhas de Cabo Verde (C-V) e no Brasil (BRA), em especial no estado do Cearà visando uma comparaÃÃo desses produtos. ApÃs o estudo das melhores condiÃÃes cromatogrÃficas foi possÃvel uma anÃlise simultÃnea de seis compostos orgÃnicos volÃteis: acetaldeÃdo, acetato de etila, e os Ãlcoois, n-propÃlico, isobutÃlico, n-butÃlico e isoamÃlico. TambÃm foram estudados os compostos inorgÃnicos, cÃtions (Na+, K+, Cu2+, Ca2+, Mg2+,Mn2+,Pb2+, Zn2+,Cd2+, Se2+ e Fe3+) e Ãnions (Cl-, CH3COO-, SO42- , CO3= e HCO3- ). Os Ãnions foram determinados por cromatografia de Ãons (CI) e cÃtions por espectrometria de emissÃo Ãtica com Plasma indutivamente acoplado (ICP- OES). A validaÃÃo dos mÃtodos foi estudada em funÃÃo dos parÃmetros, precisÃo intermediÃria (repetibilidade), recuperaÃÃo, linearidade da curva analÃtica, limite de deteÃÃo e de quantificaÃÃo. A precisÃo e a recuperaÃÃo obtidas para os Ãlcoois, aldeÃdo e Ãster presentes nas aguardentes apresentaram uma variaÃÃo na faixa de 0,2 % - 7,0 %, 0,9% -3,2%, 0,3%-0,7%; e 97,0% -103,0%, 99,3 - 104,0%, 98,2% - 102,7% respectivamente.Os limites de detecÃÃo do equipamento obtidos em mg/100 mL de Ãlcool Anidro (A.A), foram 4,2, para acetaldeÃdo; 2,8 para o acetato de etila; 9,2 para o Ãlcool n-propÃlico ; 7,8 para o Ãlcool isobutÃlico; 3,1 para o Ãlcool n-butÃlico e 44,6 para o Ãlcool isoamÃlico. Os resultados quantitativos dos compostos orgÃnicos mostraram, que de acordo com limites mÃximos permitidos pela legislaÃÃo brasileira, dos compostos volÃteis estudados, apenas cinco das aguardentes de Cabo Verde (quatro artesanais, uma industrial) e trÃs artesanais das aguardentes do Brasil ultrapassaram o limite permitido pela legislaÃÃo em teores de acetaldeÃdo;relativamente a n-butanol, 60% e 50% das aguardentes industrial e artesanal de Cabo-Verde e Brasil respectivamente apresentam teores superiores ao limite mÃximo estipulado (3,0 mg/100 mL A.A). Das dez aguardentes brasileiras, que ultrapassaram o limite, trÃs sÃo industriaise sete artesanais enquanto que das doze aguardentes de Cabo-Verde que ultrapassaram em teores esse limite, seis sÃo artesanais e seis industriais. Dentre Ãlcoois superiores, duas industriais e uma artesanal de Cabo-Verde e duasartesanais do Brasil ultrapassaram o limite mÃximo referido. Os resultados mÃdios, em mg/100 mL A.A, para os compostos orgÃnicos presentes nas aguardentes de Cabo Verde e do Brasil, indicam que oacetaldeÃdo e Ãlcoois superiores se encontram dentro dos padrÃes de qualidade exigidos pela legislaÃÃo brasileira (30 mg/100 mL A.A para aldeÃdos; 360 mg/100 mL A.A para Ãlcoois superiores) e tem a mesma magnitude para as aguardentes de ambos paÃses 17,2 (BRA) -17,6 (CV) mg/100 mL A.A em acetaldeÃdo, e 247,4 (BRA) -240,6 (CV) mg/100 mL A.A em Ãlcoois superiores. Em contraste o acetato de etila se encontra em menor concentraÃÃo nas aguardentes do Brasil estudadas (24,8 mg/100 mL A.A) em relaÃÃo aos aguardentes de Cabo Verde (70,0mg/100 mL A.A). A comparaÃÃo dos resultados obtidos, em mg/100 mL A.A, para os cÃtions e Ãnions estudados mostrou a seguinte relaÃÃo: Ni2+ 0,7(BRA) - 0,6(C-V); Se2+ 1,6(BRA) - 0,62(C-V); Cd2+0,03 (BRA) - 0,04(C-V); Cu2+.5,6(BRA)-9,2(C-V); CH3COO- 055 (BRA) -1,3(C-V); SO42- 0,07(BRA) - 4,9(C-V); HCO3-0,04 (BRA) - 9,2(C-V); e Cl- 0,56 (BRA) - 2,0(CV). Os valores mÃdios das concentraÃÃes dos compostos inorgÃnicos nas aguardentes estudadas do Brasil e de Cabo Verde diferem entre si, mas sÃo concordantes com os dados da literatura exceto para o cobre, que ultrapassa o limite permitido em ambos os paÃses. Na anÃlise para reconhecimento de padrÃes utilizou-se a ferramenta quimiomÃtrica âAnÃlise de Componentes Principaisâ, PCA, que mostrou uma evidente separaÃÃo das amostras das aguardentes artesanais e industriais dos dois paÃses estudadas.
The aim of this work was to develop/adapt and validate analytical methods to both identify and quantify constituents of greater concern regarding the quality of homemade and industrial sugar cane spirits produced in some islands from Cape-Vert (CV) and in some states â especially Cearà and Piauà â from Brazil (BRA), so that different products can be compared to one another. After optimization of chromatographic conditions, simultaneous analysis was feasible for six volatile compounds, namely: acetaldehyde and ethyl acetate, as well as n-propyl, isobutyl, nbutyl, and isoamyl alcohols. The inorganic composition of the samples was also investigated. Anions (Cl-, CH3COO-, SO4 2- , CO3 = e HCO3 -) were analysed by Ion Chromatography, while cations (Na+, K+, Cu2+, Ca2+, Mg2+,Mn2+,Pb2+, Zn2+,Cd2+, Se2+ e Fe3+) were analysed by Inductively Coupled Plasma-Optical Emission Spectrometry. The methodologies were validated considering the parameters repeatability, recovery, linearity of analytical curve, limit of detection, and limit of quantitation. For alcohols, aldehyde, and ester analysed, precision was respectively in the ranges 0,2 % - 7,0 %, 0,9% -3,2%, 0,3%-0,7%, while recovery varied in the ranges 97,0% - 103,0%, 99,3 - 104,0%, 98,2% - 102,7%, respectively. The limits of detection (mg/100 mL A.A) were 4.2 for acetaldehyde, 2.8 for ethyl acetate, 9.2 for npropyl alcohol, 7.8 for isobutyl alcohol, 3.1 for n-butyl alcohol, and 44.6 for isoamyl alcohol. The results showed that in only five samples from Cape-Vert (four homemade; one industrial) and in three home-made samples from Brazil, the levels of acetaldehyde were found to be higher than the upper limits allowed by Brazilian legislation; the concentrations of n-butyl alcohol were higher than the allowed limits in two samples from Cape-Vert (one home-made; one industrial) and three home-made samples from Brazil. The levels of higher alcohols were higher than the limit concentrations in three samples from Cape-Vert (one home-made; two industrial) and in two home-made samples from Brazil. However, average concentrations (mg/100 mL A.A) of both acetaldehyde (17,2 BRA; 17,6 C-V) and higher alcohols (247,4 BRA; 240,6 C-V) are in accordance with the requirements of Brazilian legislation (30 mg/100 mL A.A for aldehydes; 360 mg/100 mL A.A for higher alcohols). Ethyl acetate concentration (mg/100 mL A.A) was found to be lower in samples from Brazil (24.8 BRA; 70.0 C-V). The concentrations (mg/100 mL AA) of both cations and anions were found to be: Ni2+ 0,7 (BRA) - 0,6(C-V); Se 1,6(BRA)- 0,62(C-V); Cd2+0,03 (BRA)- 0,04(C-V); Cu2+.5,6 (BRA) - 9,2 (C-V); CH3COO- 055 (BRA) - 1,3 (C-V); SO4 2- 0,07 (BRA) - 4,9 (C-V); HCO3 - 0,04 (BRA) - 9,2(C-V); e Cl- 0,56 (BRA) - 2,0(CV). Average concentrations of inorganic compounds in the samples from Brazil and from Cape-Vert differ from each other, but are in accordance with the literature, except for copper, which is in higher concentrations than allowed in both countries. By PCA analysis, groups were identified in bi-dimensional graphs, in which both artisanal and industrial samples were clearly separated
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Bouaziz, Jordan. "Mémoires ferroélectriques non-volatiles à base de (Hf,Zr)O2 pour la nanoélectronique basse consommation". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI057.
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Depuis 2005, la miniaturisation des composants mémoires, qui, auparavant, suivait la loi de Moore, a ralenti. Ceci a conduit les chercheurs à multiplier les approches pour continuer à améliorer les dispositifs mémoires. Parmi ces approches, la piste des composants ferroélectriques semble très prometteuse. En 2011, une équipe du NamLab, à Dresde, en Allemagne, a découvert que le HfO2 dopé Si pouvait devenir ferroélectrique, avec une couche isolante de seulement 10 nm, ce qui résout le problème de compatibilité avec l’industrie CMOS des matériaux de structure pérovskite. Depuis, d’autres dopants ont été découverts. Cependant, de nouveaux problèmes freinent désormais l’apparition sur le marché des dispositifs ferroélectriques à base de HfO2. Comprendre les mécanismes qui régissent les propriétés ferroélectriques de ces matériaux est alors devenu un enjeu industriel majeur. Dans ce manuscrit, nous étudions le (Hf,Zr)O2 (HZO), et nous employons une technique peu utilisée pour élaborer ce type de matériau : la pulvérisation cathodique magnétron. L’objectif de cette thèse est d’établir des relations entre les conditions de croissance des différents matériaux et les propriétés électriques, de comprendre les mécanismes qui les régissent, ainsi que de rendre viable les dispositifs mémoires. Lors de l’élaboration de condensateurs, nous démontrons que des propriétés cristallochimiques particulières sont indispensables pour obtenir la ferroélectricité, et de nouvelles propriétés du HZO sont découvertes. Ensuite, nous cherchons à dépasser l’état de l’art. Par pulvérisation, nous obtenons parmi les meilleurs résultats au monde. Les tests industriels d’endurance et de rétention sont poussés au-delà de ce qui avait été fait auparavant dans la littérature. En particulier, l’influence des conditions de contraintes électriques y est décrite en détail, et nous mettons en évidence la présence d’une relaxation au cours des différents tests pouvant s’avérer problématique pour l’avènement d’applications industriels. Ce problème ne semble jamais avoir été clairement identifié auparavantSince 2005, the scaling of memory devices, which used to follow Moore's law, slowed down. This lead researchers to conduct multiple approaches in order to keep improving memory devices. Among these approaches, the pathway on ferroelectric components seems very promising. In 2011, a research team from the NamLab in Dresden, Germany, discovered that Si-doped HfO2 could become ferroelectric with an insulating layer of only 10 nm, which resolves the compatibility issue of perovskite-structured materials with CMOS industry. Since then, other dopants have been investigated. However, new issues are now slowing down the emergence of HfO2-based ferroelectric devices on the market. Understanding the mechanisms behind the ferroelectric properties of these materials has, therefore, become a major industrial issue. In this manuscript, we study (Hf,Zr)O2 (HZO), and we perform an under-utilized technique to elaborate this kind of material: magnetron sputtering. The goal of this thesis is to establish connections between the growth conditions of this material and the electrical properties, to understand the mechanisms behind them, as well as to make the memory devices viable. During the fabrication of the capacitors, we demonstrate that the particular cristallochemical properties are essential to obtain ferroelectricity, and that novel HZO properties are discovered. Afterwards, we seek to cross the state of the art. The results we obtain by sputtering are among the best in the world. The industrial endurance and retention tests are pushed beyond what has been done in the literature so far. Particularly, the influence of electrical stress conditions is thoroughly detailed, and we put to evidence the presence of a relaxation during the different tests that could turn out to become problematic for the emergence of industrial applications. It does not seem that this problem has been identified beforehand
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Carvalho, Adriana Vidal França de. "Controle de emissões fugitivas de compostos orgânicos voláteis em componentes de linhas de processo de refinarias de petróleo". Universidade Federal Fluminense, 2016. https://app.uff.br/riuff/handle/1/2800.
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O impacto na qualidade do ar causado pela emissão de poluentes atmosféricos tem sido um problema ambiental crescente, especialmente nos centros urbanos e nas áreas industriais. O ozônio, formado por reações fotoquímicas, é um dos principais componentes do smog fotoquímico. Devido às suas características oxidantes ele é prejudicial à saúde e ao meio ambiente. Por ser um poluente secundário, o controle dos níveis de ozônio na troposfera deve ser realizado a partir da redução dos seus principais precursores: COVs e óxidos de nitrogênio. Refinarias de petróleo são importantes fontes de COVs, especialmente de emissões fugitivas de componentes de linhas de processo e, portanto, são fontes onde há potencial para reduzir estas emissões. Além disso, as licenças ambientais das refinarias também exigem a redução de emissões fugitivas de COVs. A metodologia LDAR, baseada no uso de um analisador portátil para identificação de vazamentos em componentes de linhas de processo, vem sendo utilizada nos Estados Unidos desde a década de 70 para a redução das emissões fugitivas de COVs em refinarias de petróleo. É uma metodologia bastante intensiva em mão de obra e tem custo elevado, uma vez que exige o monitoramento individual de milhares de componentes existentes em uma planta industrial para a detecção de vazamentos. Porém, estudos mostram que o controle com foco nos grandes vazamentos permite uma redução mais efetiva das emissões fugitivas e com menor custo. A metodologia Smart LDAR, que consiste no uso de imagem ótica de infravermelho para visualização de gases, permite a identificação dos grandes vazamentos, que são os que mais contribuem para as emissões fugitivas, sem que haja necessidade de medição de todos os componentes das linhas de processo. O objetivo desta pesquisa é avaliar as metodologias LDAR (Leak Detection and Repair) e Smart LDAR, utilizadas para o controle de emissões fugitivas de compostos orgânicos voláteis (COVs) em refinaria de petróleo, utilizando o conceito de custo-efetividade. Os resultados obtidos a partir das avaliações realizadas mostraram que a metodologia Smart LDAR tem melhor relação custo efetividade para o controle de emissões fugitivas de COVs em comparação à metodologia LDAR convencional
The impact on air quality caused by air pollutants emissions has proven to be a growing environmental problem, mainly at urban centers and industrial areas. The ozone, formed through photochemical reactions, is the photochemical smog’s major component. Due its oxidizing characteristics, it is harmful to the healthy and to the environment. Due to de fact to be a secondary pollutant, the ozone control in the troposphere must be achieved by reducing emissions from its main precursors: VOCs and nitrogen oxides. Petroleum refineries are significant sources of VOCs, especially of fugitive emissions from process lines’ components, so they are sources with potential to reduce these emissions. Furthermore, the petroleum refineries’ environmental licenses also demand the reduction of VOCs’ fugitive emissions. The LDAR methodology, which is based on the application of a portable analyzer to identify leaks in process lines’ components, has been used in the US since the 70s to reduce VOCs’ fugitive emissions in petroleum refineries. This methodology is quite intensive hand labor and costly, since an industrial plant has thousands of components that must be measured individually to detect leaks. However, studies show that the control focusing on large leaks allows the reduction of fugitive emissions more effectively and with low costs. The methodology known as Smart LDAR, which uses infrared optical image for gas leaks view, has the potential to identify great leaks, that most contribute to the fugitive emissions, without requirement to measure all process lines’ components. The purpose of this research is evaluate the methodologies LDAR (Leak Detection and Repair) and Smart LDAR, used to control volatile organic compounds’ (VOCs) fugitive emissions in petroleum refineries, using the concept of cost-effective analysis. The results obtained from the evaluations of this study showed that the Smart LDAR methodology has the best cost effective relation to control fugitive emissions compared to the LDAR conventional methodology
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Bragatto, Álann de Oliveira Piagentini. "Sistema de pintura anticorrosiva monocomponente aplicado diretamente sobre o metal substituto ao sistema tradicional de três componentes - Desenvolvimento e avaliação de formulações de tinta base água". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/46/46137/tde-24082018-082657/.
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O trabalho desenvolvido tem como objetivo avaliar um sistema de pintura anticorrosiva aplicado diretamente sobre o metal, sistema DTM, em relação a um sistema tradicional, composto por Primer, Intermediário e Top Coating, ambos base solventes e destinados para aplicações arquitetônicas, e propor o desenvolvimento e avaliação de formulações base água substitutas à base solvente, procurando-se determinar a influência de determinados componentes presentes nas formulações, tais como o dióxido de titânio, fosfato de zinco, caulim, inibidor de corrosão orgânico e agente reticulante nas propriedades anticorrosivas da tinta. São realizadas avaliações das propriedades anticorrosivas das tintas por meio de medidas de potencial de circuito aberto (EOCP), espectroscopia de impedância eletroquímica (EIS) e ensaio acelerado de corrosão em câmara de névoa salina. Além das propriedades anticorrosivas, as tintas DTM base água formuladas são avaliadas comparativamente à tinta DTM base solvente em outras propriedades, particularmente em relação à resistência à água, por meio de medidas de absorção de água, permeabilidade ao vapor dágua e determinação do ângulo de contato, e em relação às propriedades estéticas, tais como o poder de cobertura de tinta úmida e seca. Os resultados demonstram que o sistema DTM basesolvente apresenta desempenho anticorrosivo equivalente ao sistema tradicional. Dentre as formulações base água avaliadas, verifica-se que o uso do fosfato de zinco como pigmento anticorrosivo e de um agente reticulante na formulação é fundamental para se obter um desempenho anticorrosivo satisfatório. Também é demonstrado que a resistência à água dos filmes é um fator fundamental a ser melhorado nas tintas base água para que se possa obter resultados satisfatórios em relação à resistência à corrosão para longos períodos de exposição como o obtido para o sistema base solvente.The developed work aims to evaluate an anticorrosive paint system applied directly on metal, DTM system, in relation to a traditional three components paint system, composed by Primer, Intermediary Coating and Top Coating - both systems solvent based and intended to architectural applications. The work also aims to develop and evaluate water based DTM paint formulations in substitution to solvent based paint system, determining the influence of some components present in the formulations, such as titanium dioxide, zinc phosphate, kaolin, organic corrosion inhibitor and a crosslinker agent, in the anticorrosive properties of the paint. The anticorrosive properties of the paint are evaluated by open circuit potential measures (EOCP), electrochemical impedance spectroscopy (EIS) and accelerated corrosion test in the salt-spray chamber. Besides the anticorrosive paints properties, water based DTM formulated paints are compared to solvent borne DTM paint in other properties, particularly in relation to water resistance, by measures of water absorption, water vapor permeability and contact angle, and also in relation to aesthetic properties, such as dry and wet hiding power. The results demonstrated that anticorrosive performance of solvent borne DTM paint system is similar to the solvent borne traditional paint system. In relation to formulatedwater based DTM paints, it was observed that the use of zinc phosphate as an anticorrosive pigment and a crosslinker agent in the formulation is essential to obtain a satisfactory anticorrosive performance. It is also demonstrated that the paint films water resistance is a fundamental property to be improved in water based paints in order to obtain satisfactory results in relation to corrosion resistance for long periods of exposure, just as observed for solvent borne system.
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"Principal component analysis of the volatile flavor components and the lexicons of the commercial plain fermented soybean curds". 2004. http://library.cuhk.edu.hk/record=b5892128.
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Fung Pui-kwan.Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references (leaves 128-153).
Abstracts in English and Chinese.
Abstract (in English) --- p.i
Abstract (in Chinese) --- p.iv
Acknowledgement --- p.vi
Contents --- p.vii
List of Figures --- p.xi
List of Tables --- p.xii
Chapter 1. --- Introduction --- p.1
Chapter 2. --- Literature review --- p.5
Chapter 2.1 --- Soybean --- p.5
Chapter 2.1.1 --- History of soybean --- p.5
Chapter 2.1.2 --- Composition of soybean --- p.6
Chapter 2.1.3 --- Nutritional value and health implications of soybean --- p.6
Chapter 2.2 --- Soyfoods --- p.8
Chapter 2.2.1 --- Nonfermented oriental soyfoods --- p.8
Chapter 2.2.2 --- Fermented oriental soyfoods --- p.9
Chapter 2.2.2.1 --- Soy sauce --- p.9
Chapter 2.2.2.2 --- Miso --- p.12
Chapter 2.2.2.3 --- Natto --- p.13
Chapter 2.2.2.4 --- Tempeh --- p.13
Chapter 2.2.2.5 --- Black bean --- p.14
Chapter 2.3 --- Sufu --- p.15
Chapter 2.3.1 --- History of sufu --- p.15
Chapter 2.3.2 --- Sufu classification --- p.16
Chapter 2.3.3 --- Sufu production --- p.17
Chapter 2.3.4 --- Flavor origin of sufu --- p.22
Chapter 2.3.5 --- Volatile components of sufu --- p.23
Chapter 2.3.5.1 --- Alcohols --- p.23
Chapter 2.3.5.2 --- Aldehydes --- p.23
Chapter 2.3.5.3 --- Esters --- p.24
Chapter 2.3.5.4 --- Furans --- p.25
Chapter 2.3.5.5 --- Ketones --- p.26
Chapter 2.3.5.6 --- Sulfur containing compounds --- p.27
Chapter 2.4 --- Sensory evaluation and statistical analysis of data --- p.27
Chapter 2.4.1 --- Types of sensory evaluation techniques --- p.28
Chapter 2.4.1.1 --- Discriminative sensory analysis --- p.28
Chapter 2.4.1.2 --- Consumer affective tests --- p.28
Chapter 2.4.1.3 --- Sensory descriptive analysis --- p.29
Chapter 2.4.2 --- The use of lexicons in sensory analysis --- p.30
Chapter 2.4.3 --- The use of multivariate statistical analyses in sensory evaluation --- p.31
Chapter 2.4.3.1 --- Multivariate Analysis of Variance (MANOVA) and Descriptive Discriminant Analysis (DDA) --- p.33
Chapter 2.5 --- Relationship between instrumental and sensory data of commercial plain sufu --- p.34
Chapter 2.5.1 --- Principal components analysis of sufu samples --- p.35
Chapter 2.6 --- Objectives of the study --- p.36
Chapter 3. --- Volatile components in sufu --- p.37
Chapter 3.1 --- Introduction --- p.37
Chapter 3.2 --- Materials and Methods --- p.41
Chapter 3.2.1 --- Sample collection and preparation --- p.41
Chapter 3.2.2 --- Supercritical fluid extraction (SFE) conditions --- p.41
Chapter 3.2.3 --- Gas chromatography-mass spectrometry (GC-MS) conditions --- p.42
Chapter 3.2.4 --- Qualification and Quantification of Volatile Compounds --- p.43
Chapter 3.2.5 --- Gas chromatography-Flame Ionization Detection-Olfactometry (GC-FID-O) --- p.44
Chapter 3.2.6 --- Omission experiments --- p.45
Chapter 3.2.7 --- Statistical analysis --- p.46
Chapter 3.3 --- Results and discussion --- p.49
Chapter 3.3.1 --- Overall findings --- p.49
Chapter 3.3.2 --- Acids --- p.54
Chapter 3.3.3 --- Alcohols --- p.55
Chapter 3.3.4 --- Aldehydes --- p.55
Chapter 3.3.5 --- Other TV-containing compounds --- p.56
Chapter 3.3.6 --- Esters --- p.57
Chapter 3.3.7 --- Furans --- p.58
Chapter 3.3.8 --- Ketones --- p.58
Chapter 3.3.9 --- Miscellaneous compounds --- p.59
Chapter 3.3.10 --- Sulfur-containing compounds --- p.60
Chapter 3.3.11 --- Gas chromatography-flame ionization detection-olfactometry 6() (GC-FID-O) analysis --- p.60
Chapter 3.3.12 --- Omission experiments --- p.66
Chapter 3.4 --- Conclusion --- p.69
Chapter 4. --- Sufu lexicon development and spectrum analysis of the flavor of sufu --- p.70
Chapter 4.1 --- Introduction --- p.70
Chapter 4.2 --- Materials and Methods --- p.71
Chapter 4.2.1 --- Samples collection and preparation --- p.71
Chapter 4.2.2 --- Basic design --- p.72
Chapter 4.2.3 --- Selection of panelists......Prescreening --- p.73
Chapter 4.2.4 --- Selection of panelists......Screening --- p.74
Chapter 4.2.5 --- Panelist selection --- p.81
Chapter 4.2.6 --- Panelist training --- p.82
Chapter 4.2.7 --- Definition and preparation of the reference standards and scale setting --- p.85
Chapter 4.2.8 --- Product evaluation --- p.92
Chapter 4.2.9 --- Statistical analysis --- p.93
Chapter 4.3 --- Results and discussion --- p.95
Chapter 4.3.1 --- Reduction of the number of lexicons --- p.95
Chapter 4.3.2 --- Analysis of variance (ANOVA) --- p.103
Chapter 4.3.3 --- Overall product differences-pooled within canonical structure --- p.104
Chapter 4.3.4 --- Sufu lexicons --- p.104
Chapter 4.3.5 --- Comparison of sufu lexicons with its related products --- p.108
Chapter 4.4 --- Conclusion --- p.109
Chapter 5. --- Statistical Analysis of Chemometrics and Psychometrics of sufu --- p.112
Chapter 5.1 --- Introduction --- p.112
Chapter 5.2 --- Materials and methods --- p.114
Chapter 5.3 --- Results and discussion --- p.114
Chapter 5.3.1 --- Selection of the best number of factors --- p.114
Chapter 5.3.2 --- Meaning of PC --- p.118
Chapter 5.4 --- Conclusion --- p.124
Chapter 6. --- General Conclusion and Significance of the Study --- p.125
References --- p.128
Appendix --- p.154
38
Wu, Daniel, i 吳書育. "Mass transfer modeling for multi-component volatile organic compounds (VOCs) in vapor permeation process". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/77031653820480783780.
Pełny tekst źródłaStreszczenie:
碩士長庚大學
化工與材料工程研究所
93
In the study, the sorption and diffusion and flux of methanol, m-xylene, toluene, iso-pentane, water through a polydimethylsiloxane (PDMS) membrane was studied. Used experimental data and various model by explaining that mass transfer modeling for multi-component volatile organic compounds (VOCs) in vapor permeation process. The behavior of sorption divided into single system and binary system, that modeled by Flory-Huggins model and UNIQUAC model. In single system, UNIQUAC model slightly superior to Flory-Huggins model. On the other hand, Flory-Huggins model superior to far UNIQUAC model in binary system. I can knew to assessed all results, used Flory-Huggins model to described that the behavior of sorption is ideally and appropriately. In the behavior of diffusion divided into single system and binary system, too. In single system, the diffusion coefficient decreases with increasing feed activity, except for m-xylene. The Long’s model can be accepted to estimate the diffusion coefficient. Else, found too in binary system, the diffusion coefficient in single system can be used in binary system, and independent with the other component. According to solution-diffusion mechanism, the mass transfer process in vapor permeation modeled and interpreted by Fick’s first law. The result showing that the flux increases with increasing feed activity. In binary system, the result can be influenced obviously by the property to be not similar to between two components. Summarize all the above results, this study will setting up the modeling successfully and fully for everybody to study and discuss.
39
Han, Kun-Yu, i 韓坤佑. "Implementation of a novel microwave plasma reactor and its application on volatile organic component treatment". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/27406188849092734994.
Pełny tekst źródłaStreszczenie:
碩士國立中興大學
化學工程學系
90
ABSTRACT A novel microwave plasma system was implemented and applied on the volatile organic compounds (VOCs) treatment. Ethanol and acetone were selected as the target VOCs respectively. The decomposition and removal efficiency (DRE) value was used to evaluate the performance of the microwave plasma system. Oxygen, air and H2O add to air were used as carriers to combine with the VOCs and to facilitate the VOCs treatment. Under the optimal conditions, namely, flow rate of ethanol was 1500 sccm, power input was 1.5 KW at a frequency of 1KHz, flow rate of air was 1000 sccm and the flow rate of H2O was 0.3 ml/min, an efficiency high than 97% DRE value could be obtained for both ethanol and acetone. Due to the high efficiency and high capacity, this system could be an potential alternation in industrial VOCs treatment.
40
Ru, Wu Man, i 吳曼如. "Effect of 2,4,5-trimethoxybenzaldehyde,the Major Volatile Component of Antrodia camphorate Fruiting Body, on 3T3-L1 Adipocytes". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/17891921436232215420.
Pełny tekst źródłaStreszczenie:
碩士實踐大學
食品營養與保健生技學系碩士班
100
Obesity is considered a major risk factor for many chronic disease, including hypertension, type 2 diabetes, and atherosclerosis.The fruiting bodies of Antrodia camphorate possess various biological activites, including anti-oxidation, anti-hypertension, anti-carcinogenesis, anti-hyperlipidemia and liver-protection. However, there has not been any study related to anti-obesity. The major volatile compound of Antrodia camphorate fruiting body, 2,4,5-trimethoxybenzaldehyde (2,4,5-TMBA), was reported to be a significantly inhibitor of COX-2 activity. Because COX-2 is essential for adipogenesis, we investigated the effect of 2,4,5-TMBA on 3T3-L1 preadipocytes differentiation and adipocytes lipolysis. During differentiation, 2,4,5-TMBA dose-dependently attenuated lipid accumulation in differentiated adipocyte as evidenced by Oil Red O staining. At the molecular level, 2,4,5-TMBA decreased the protein expression of MAP kinase kinsae (MEK), extracellular signal-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK), CCAAT/enhancer binding protein (C/EBP) α,β,γ, peroxisome proliferator-activated receptor (PPAR) γ, adipocyte determination and differentiation-dependent factor1/sterol regulation element binding protein1c (ADD1/SREBP1c), acetyl-CoA carboxylase (ACC), and perilipin A. In mature adipocytes, 2,4,5-TMBA singnificantly decreased intracellular lipid accumulation by increasing the lipolysis of triglyceride though suppression of perilipin A and up-regulation of hormone-sensitive lipase (HSL). These results demonstrate that 2,4,5-TMBA efficiently inhibits adipogenesis and increase lipolysis in 3T3-L1 cells. Keywords：2,4,5-TMBA, adipogenesis, lipolysis, 3T3-L1 cells
41
Choudhury, Belayet H. "Volatile and non-volatile components of beef marrow bone stocks". 2008. http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17449.
Pełny tekst źródła
42
Ke, Hung-Ta, i 柯宏達. "Studies on Antioxidative and Volatile Components of Pogostemon cablin". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/01081351313603900408.
Pełny tekst źródłaStreszczenie:
碩士東海大學
食品科學系
90
The purposes of this study were to investigate antioxidative and volatile components from Pogostemon chablin. The results were summarized as the following: (1) The antioxidative components of Pogostemon chablin The ground powder of Pogostemon chablin was extracted with n-hexane, ethyl acetate and methanol. The antioxidative activity of the extract was measured by the ferric thiocyanate method. The order of antioxidative activity was : BHA > methanol extract > α-tocopherol > ethyl acetate extract > n-hexane > control. Due to the strong antioxidative activity of methanol extract, it was fractionated and isolated by various chromatographies to obtain three pure components— adenosine、4-hydroxyethyl- catachol-1-O- (2’-α- L- rhamnopyranosyl)-β- D- glucopyranoside及ο- coumaroyl-β- D- glucopyranoside. (2) Volatile components of Pogostemon chablin The volatile extract was obtained from Pogostemon chablin by Likens-Nickerson extraction and supercritical carbon dioxide extraction. It was isolated and identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The 19 components of the volatile extract had been identified, including 6 alcohols, 10 terpenes, 1 ester, 1 acid and 1 phenolic compound . The antioxidative activity of the volatile extract and the various solvent extract was analyzed by the ferric thiocyanate method. The order of antioxidative activity was: BHA > methanol extract >α-tocopherol > volatile extracts > ethyl acetate extract > n-hexane > supercritical carbon dioxide extract > Likens-Nickerson extraction > control
43
Sue, Kai_Hsin, i 蘇凱馨. "Studies on the antimicrobial volatile components from the plant". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/45845737070261920411.
Pełny tekst źródłaStreszczenie:
碩士國立屏東科技大學
食品科學系
93
The aim of this study is to identify the volatiles and their antimicrobial activites of lotus flower (Nelumbo nucifera), Plectlanthus, Cinnamomum osmophloeum Kaneh. Volatiles were extracted through three methods including steam distillation, solid-phase microextraction and headspace technique, and then characterized by gas chromatography equipped with mass detector before antimicrobial analysis. Results showed that, more than fifty-one volatiles were identified from petal, filament, pollen and sepal of two varieties in lotus flower. The volatiles compounds in the filaments, sepals and petals were found to be less than that in pollen. Fifty-five compounds, mainly carvacrol and β-caryophyllene were identified from leaves of four varieties of Plectlanthus. As to the Cinnamomum osmophloeum Kaneh, there were also fifty-two compounds identified with the major component as cinnamaldehyde. Higher cinnamaldehyde and lower cinnamyl acetate was found in the sample from higher elevation place. Further antimicrobial analysis of the volatile constituents from sample mentioned above showed that carvacrol, β-caryophyllene, cinnamaldehyde, cinnamyl acetate, trans-cinnamic acid and cinnamyl alcohol exhibited the antimicrobial activites. Minimum inhibitory concentration (MIC) were determined against 6 bacteria, 3 yeast and 4 fungi through agar diffusion method. The growth of Bacillus subtilis, Listeria monocytogenes, Staphylococcus epidermidis, Flavobacterium , Pseudomonas aeruginosa, Salmonella typhimurium, Rhizoctonia solani, Fusarium oxysporum f.sp. melonis FOM-M2, Fusarium oxysporum f.sp. melonis FOM-M3, Fusarium oxysporum f.sp. melonis FOM-M9 was completely inhibited by carvacrol, cinnamaldehyde, trans-cinnamic acid at relatively low concentrations (1~3 mM). However, β-caryophyllene and cinnamyl acetate showed no antimicrobial activities at all. Finally, the effects of cinnamaldehyde and cinnamyl acetate on the cytotoxicity, induction of apoptosis in K562 cells were investigated through MTT assay as well. The cinnamaldehyde showed stronger cytotoxicity on K562 cells than cinnamyl acetate, with a survival of 29.85% and 83.35% at 100 µM, respectively. Flowcytometry also showed their sub-G1 as 71.62% and 21.29% at 200 µM, respectively. Further investigation by DNA fragmentation and fluorescence microscope confirmed the truth that cinnamaldehyde is a potent inducer of apoptosis.
44
Richards, Larissa Christine. "Chemometric analysis of full scan direct mass spectrometry data for the discrimination and source apportionment of atmospheric volatile organic compounds measured from a moving vehicle". Thesis, 2021. http://hdl.handle.net/1828/13333.
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Anthropogenic emissions into the troposphere can impact air quality, leading to poorer health outcomes in the affected areas. Volatile organic compounds (VOCs) are a group of chemical compounds, including some which are toxic, that are precursors in the formation of ground-level ozone and secondary organic aerosols. VOCs have a variety of sources, and the distribution of atmospheric VOCs differs significantly over time and space. Historically, the large number of chemical species present at low concentrations (parts-per-trillion to parts-per-billion by volume) have made VOCs difficult to measure in ambient air. However, with improvements in analytical instrumentation, these measurements are becoming more common place. Direct mass spectrometry (MS), such as membrane introduction mass spectrometry (MIMS) and proton-transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) facilitate real-time, continuous measurements of VOCs in air, with full scan mass spectral data capturing changes in chemical composition with high temporal resolution. Operated on-road, mobilized direct MS has been used for quantitative mapping of VOCs at the neighborhood scale, but identifying VOC sources based on the observed mixture of molecules in the full scan MS dataset has yet to be explored. This dissertation describes the use of chemometric techniques to interrogate full scan MS data, and the progression from discriminating VOC samples of known chemical composition based on full scan MIMS data through to the apportionment of VOC sources measured continuously with a PTR-ToF-MS system operating in a moving vehicle. Lab‐constructed VOC samples of known chemical composition and concentration demonstrated the use of principal component analysis (PCA) to discriminate, and k-nearest neighbours to classify, samples based on normalized full scan MIMS data. Furthermore, multivariate curve resolution-alternating least squares (MCR-ALS) was used to resolve mixtures into molecular component contributions. PCA was also used to discriminate ‘real-world’ VOC mixtures (e.g., woodsmoke VOCs, headspace above aqueous hydrocarbon samples) of unknown chemical composition measured by MIMS. Using vehicle mounted MIMS and PTR-ToF-MS systems, full scan MS data of ambient atmospheric VOCs were collected and PCA was applied to the normalized full scan MS data. A supervised analysis performed PCA on samples collected near known VOC sources, while an unsupervised analysis using PCA followed by cluster analysis was used to identify groups in a continuous, time series PTR-ToF-MS dataset measured between Nanaimo and Crofton, British Columbia (BC). In both the supervised and unsupervised analysis, samples impacted by emissions from different sources (e.g., internal combustion engines, sawmills, composting facilities, pulp mills) were discriminated. With PCA, samples were discriminated based on differences in the observed full scan MS data, however real-world samples are often impacted by multiple VOC sources. MCR-weighted ALS (MCR-WALS) was applied to the continuous, time series PTR-ToF-MS data from three field campaigns on Vancouver Island, BC for source apportionment. Variable selection based on signal-to-noise ratios was used to reduce the mass list while retaining the observed m/z that capture changes in the mixture of VOCs measured, improving model results, and reducing computation time. Both point (e.g., anthropogenic hydrocarbon emissions, pulp mill emissions) and diffuse (e.g., VOCs from forest fire smoke) VOC sources were identified in the data, and were apportioned to determine their contributions to the measured samples. The data analyzed captured fine scale changes in the ambient VOCs present in the air, and geospatial maps of each individual source, and of the source apportionment were used to visualize the distribution of VOC sources across the sampling area. This work represents the first use of MCR-WALS to identify and apportion ambient VOC sources based on continuous PTR-ToF-MS data measured from a moving vehicle. The methods described can be applied to larger scale field campaigns for the source apportionment of VOCs across multiple days to capture diurnal and seasonal variations. Identifying spatial and temporal trends in the sources of VOCs at the regional scale can help to identify pollution ‘hot spots’ and inform evidence-based public policy for improving air quality.Graduate
2022-08-17
45
陳偉元. "Studies on volatile components and color of Monascus sufu products". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/19232901733050985947.
Pełny tekst źródłaStreszczenie:
碩士大葉大學
食品工程研究所
88
Abstract Taiwan Sufu is a traditionally fermented soybean curd product. It is generally prepared using Tofu and soybean moulds and ageing in the salt-sugar brine solution with ethanol. In this study, Monascus Sufu was prepared using Monascus sp-fermented rice and aging in brine solution with or without ethanol. From the 75-day aged Sufu products by sensory-evaluation analysis, the suitable brine solution contained 20g NaCl and 30g sugar without ethanol. By viewing color evaluation, the acceptable brine solution contained 20g NaCl and 60g sugar with 40-degree ethanol. The color of Sufu products changed to red as increasing sugar content in brine solution. In this study, the volatile compounds in Monascus Sufu products were identified and quantified by GC and GC-MS. A total of 55volatile compounds were identified including 20 esters, 17 alcohols, 4 ketones, 4 acids, 4 aldehydes, 3 hydrocarbons and 3 other compounds from the 75-day aged Sufu products. For Monascus sp-fermented rice, the total of 75 volatile compounds were identified including 17 ketones, 14 alcohols, 6 acids, 12 aldehydes, 9 hydrocarbons, 1 pyrazine, 7 esters and 9 others, while the total of 34 volatile compounds were identified including 4 ketones, 10 alcohols, 4 acids, 7 aldehydes, 4 hydrocarbons, 2 esters and 3 others for commercial Tofu. The flavor of Monascus Sufu, particularly ester and alcohol, increased during the ageing period. This may be due to the contribulion of large amount contents of ketones, alcohols and aldehydes in the Monascus sp-fermented rice and Tofu. In addition, the impact of alcohol on the formation of volatile components, particularly ester, was increased as increasing the content of sugar addition. Unfortunately, the flavor of Sufu products became not acceptable as a significantly high amount of alcohol was added. In general, as the increase of sugar content in brine solution, the color, flavor and texture of the Monascus Sufu products was enhanced or improved. Keywords：Tofu, Monascus Sufu, Flavor, Monascus.
46
Huang, Hui-Ju, i 黃惠茹. "Studies on Antioxidative and Volatile Components of Pueraria lobata Flowers". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/72939404666042593219.
Pełny tekst źródła
47
Lin, Yu-Ling, i 林玉淩. "Studies on Antioxidative and Volatile Components of Dichroa febrifuga Lour". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/39526518553280595993.
Pełny tekst źródłaStreszczenie:
碩士東海大學
食品科學系
91
The purposes of this study were to investigate antioxidative and volatile components from Dichroa febrifuga Lour. The results were summarized as the following: The antioxidative components of Dichroa febrifuga Lour. The ground powder of Dichroa febrifuga Lour. was extracted with n-hexane, ethyl acetate and methanol. The antioxidative activity of the extract was measured by the ferric thiocyanate method. The order of antioxidative activity was : BHA > methanol extract > ethyl acetate extract >α-tocopherol >n-hexane extract > control. Due to the strong antioxidative activity of methanol extract, it was fractionated and isolated by various chromatographies to obtain six pure components : 4-hydroxy- 3-methoxyphenyl- 2,3-dihydroxy-1-propanone、3-[[6- O-(6-deoxy-α- L- mannopyranosyl)- β-D- glucopyranosyl] oxy] -caffeic acid 3-[(β-D-glucofuranosyl)oxy]-4-hydroxyphenyl ethyl ester、3-[(β-D 3-[(β-D-glucopyranosyl) oxy]-caffeic acid 4-[(6-deoxyl-α-L-mannopyranosyl)oxy]-phenylethyl ester、umbelliferone (7-hydroxy-coumarin）、trans ferulic acid and 3-（4-hydroxy-3-methoxyphenyl）-2-propenal . Volatile components of Dichroa febrifuga Lour. The volatile extract was obtained from Dichroa febrifuga Lour. By steam distillation extraction and supercritical carbon dioxide extraction. The extract was isolated and identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The 12 main components of the volatile extract had been identified, including 4 terpenes, 3 alcohol, 3 esters, 1 aldehyde and 1 furan . The extract yield of both extract methods are very low. Therefore, the antioxidative activity is not determinated.
48
Cheng, Yu-Chun, i 鄭宇君. "Studies on Antioxidative and Volatile Components of Artemisia argyi Leaf". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/99595326297484320121.
Pełny tekst źródłaStreszczenie:
碩士東海大學
食品科學系
92
The purposes of this study were to investigate antioxidative and volatile components from leaf of Artemisia argyi Levl. et Vant. The results were summarized as the following : （1）The antioxidative components of A.argyi The ground powder of A.argyi was extracted with n-hexane, ethyl acetate and methanol successively. The antioxidative activity of the extract was measured by the ferric thiocyanate method. The order of antioxidative activity was : BHA>methanol extract>ethyl acetate extract>α-tocopherol> control>n-hexane extract. Due to the strong antioxidative activity, the methanol extract was fractionated and isolated by various chromatographies to obtain five pure phenolic acid components : caffeyl-4-O-caffeic acid, caffeic acid,caffeyl-4-O-ferulic acid,ferulic acid,ferulyl-4-O-ferulic acid. The order of antioxidative activity was : ferulic acid>BHA>caffeic acid> caffeyl-4-O-caffeic acid>caffeyl-4-O-ferulic acid>ferulyl-4-O-ferulic acid> αtocopherol>control。 （2）Volatile components of A.argyi The volatile extract was obtained from A.argy by steam distillation- solvent extraction. The extract was isolated and identified by gas chromatography(GC) and gas chromatography-mass spectrometry(GC-MS). The 21 main components of the volatile extract had been identified, including 9 alcohols, 7 terpenes, 3 ketones and 2 phenolic compounds. The five typically volatile components of the herb are borneol(12.51%), caryophyllene oxide(7.29%), caryophyllene(6.03%), camphene(5.55%) and camphor(4.08%).
49
Chen, Ming-Hsueh, i 陳銘學. "Studies on Antioxidative and Volatile Components of Polygonum aviculare L". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/32817326405353321575.
Pełny tekst źródłaStreszczenie:
碩士東海大學
食品科學系
92
The purposes of this study were to investigate antioxidative and volatile components from Polygonum aviculare L. The results were summarized as the following: (1) The antioxidative components of P. aviculare. The ground powder of P. aviculare was extracted with methanol. Then, the methanol extract was extracted with n-hexane, ethyl acetate and methanol saccessively. The antioxidative activity of the extract was measured by the ferric thiocyanate method. The order of antioxidative activity was : BHA>ethyl acetate extract>methanol extract>n-hexane>α-tocopherol>control. Due to the strong antioxidative activity, the ethyl acetate extract was fractionated and isolated by various chromatographies to obtain four pure flavonoid glucosides, luteolin-7- O-β-D-glucopyranoside (1), apigenin 7,4’-O-β-D-diglucopyranoside (2), apigetrin（apigenin-7-O-β-D-glucopyranoside）(3) and quercetin-7,4’-O-β-D-diglucopyranoside (4). (2) Volatile components of P. aviculare The volatile extract was obtained from P. aviculare by Likens-Nickerson and supercritical carbon dioxide extractions. The extracts were isolated and identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The 33 components of the volatile extract had been identified, including 10 aldehydes, 7 alcohols, 4 esters, 3 ketones, 3 phenolic compounds, 2 acids, 2 furans and 2 terpenes . The antioxidative activity of the volatile and the various solvent extracts was analyzed by the ferric thiocyanate method. The antioxidative activity was in the order of BHA>ethyl acetate extract>methanol extract>n-hexane>α-tocopherol>control>Likens-Nickerson extract>supercritical carbon dioxide extract.
50
Wen-Chien, Tsai, i 蔡文鈐. "Studies on Volatile and Antioxidative Components from Asiasarum heterotropoides var. mandshuricum". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/23363908986633454173.
Pełny tekst źródłaStreszczenie:
碩士東海大學
食品科學系
89
Abstract The purposes of this study were to investigate volatile and antioxidative components of Asiasarum heterotropoides var. mandshuricum.The results are listed as following : (1)Volatile components of Asiasarum heterotropoides var. mandshuricum The purpose of this study section was to determinate the chemical compositions and antioxidative activities of volatile extracts from Asiasarum heterotropoides var. mandshuricum by simultaneous steam distillation solvent etraction. 22 volatile components were identified, including 2 ketones, 5 alcohols, 6 terpenes, 1 alkane, 1 phenol compounds and 7 aromatic compounds. (2) The antioxidative components from the ethyl acetate extract of Asiasarum heterotropoides var. mandshuricum Asiasarum heterotropoides var. mandshuricum was extracted witih n-hexane, ethyl acetate and methanol successively. The antioxidative activity of the extracts was determined by the ferric thiocyanate method. The antioxidative efficiency was in the ordor of BHA > ethyl acetate extract > methanol extract > α-tocopherol > n-hexane extract > control. The chromatographies to obtain four isolated compounds. Three of the isolated compounds were identified as methyl paraben (4-hydroxybenzoic acid methyl ester)、trans p-coumaric acid [3-(4-hydroxyphenyl)-2-propenoic acid]、1,2-benzenedicarboxylic acid(2-methyl butyl)ester. The rest one was tentatively concluded to be 2’-hydroxy-4’,5’-dimethyl phenyl carboxylic acid.