L'objectif de ce travail porte sur la valorisation de dérivés du calix[4]arène en tant qu'agents d'extraction sélectifs de métaux de transition, immobilisés sur polymères naturels (cellulose) ou artificiels (résines polystyrèniques). Dans une première partie, nous avons élaboré une stratégie de synthèse multi-étapes, permettant l'introduction d'unités bipyridines (n= 2 ou 3) sur la partie basse du calix[4]arène, ainsi que l'incorporation d'un bras espaceur aminé destiné au greffage. L'étude des stoechiométries Métal/Ligand avec différents cations (Zn(II), Ni(II)…) a été entreprise en solution par spectroscopie UV-visible. Dans un deuxième temps, les ligands obtenus ont alors été greffés, sur des résines PS-DVB porteuses de fonctions aldéhyde (Wang) ou chlorméthyle (Merrifield), ainsi que sur un polymère naturel (coton). Les taux de greffages obtenus ont alors été déterminés par UV-visible et par chromatographie ionique. Les capacités extractives de ces polymères en milieu aqueux/organique, ont été ensuite étudiées, tout d'abord sur des solutions monométalliques, puis sur des mélanges plus complexes. La dernière partie de notre travail a porté sur la séparation d'un mélange ternaire Ag/Zn/Pb, d'intérêt potentiellement économique, en mettant au point un processus d'extraction solide-liquide complété par le relargage sélectif en solution. Ce processus nous à amené à intégrer une étude de recyclabilité et de stabilité. La séparation effective de Ag, Zn et Pb a ainsi été démontrée. / The aim of the present work is dedicated to the valorization of calix[4]arene derivatives as transition-metal selective extraction agents, immobilized onto natural polymers (cellulose) or artificial (polystyrenic resins). We have elaborated a multi-step synthesis strategy, allowing the introduction of bipyridine units (2 or 3) on the lower rim and the incorporation of an amine spacer arm dedicated to grafting. Metal/Ligand stoechiometries studies in solution were undertaken by UV-Visible spectroscopy.Then, the ligands obtained were grafted onto PS-DVB resins functionnalized with aldehyde groups (Wang) or cholomethylene groups (Merrifield), and onto natural polymer (cotton). The grafting rates were determined by UV-Visible spectroscopy and ionic chromatography. Their extractive capacities were studied in aqueous/organic media, firstly for monometallic solutions then for more complex mixtures.The last part of our work was dedicated to the separation of a ternary mixture Ag/Zn/Pb, which could have an economic interest. A solid-liquid extraction process was developped, integrating recyclability and stability studies. The effective separation of these 3 metal ions was proved

<p>QCR 20161026</p>

La gazéification de la biomasse par voie thermochimique apparaît aujourd'hui comme une voie prometteuse pour la production de H2 et CO utilisés dans la synthèse de biocarburants. Le traitement thermique subi par la biomasse entraîne toutefois la production de composés indésirables appelés goudrons (hydrocarbures lourds) dont la teneur dans les gaz de synthèse doit être inférieure à 0,1 mg.Nm-3. Le suivi de la quantité de goudrons produits est, par conséquent, indispensable. Dans ce contexte, une méthodologie d'échantillonnage utilisant la SPME (micro-extraction sur phase solide) a été mise au point pour la quantification de "composés types" représentatifs de la quantité globale de goudrons émis principalement par deux pilotes de gazéification et de pyrolyse. L'introduction de la notion de composés types est destinée d'une part, à simplifier la méthodologie d'échantillonnage et d'autre part, à s'affranchir des éventuelles limitations liées au système de prélèvement des effluents gazeux développé dans le cadre de ce travail pour autoriser l'extraction par SPME. Pour les deux pilotes, 15 composés types ont été retenus. Leur quantification a d'abord nécessité l'étalonnage préalable des fibres SPME (revêtue de polydimethylsiloxane) qui a permis, à plusieurs températures, d'établir les profils d'absorption et de déterminer les coefficients de partage. L'influence des conditions d'extraction sur l'absorption ainsi que les performances du couplage SPME-chromatographie gazeuse ont également été évaluées. De manière à éviter les étalonnages répétitifs, un modèle basé sur la théorie des équilibres thermodynamiques a été développé pour déterminer la valeur des coefficients de partage.

No description available.

Naturally occurring plant derived phenols can be degraded through bacteria in swine waste. Chlorinated phenols, which are not naturally present in the environment, are toxic and generated from industrial activities as such petrochemical, pharmaceutical, plastic, rubber, pesticide, iron, steel, paper production, coal conversion, wood preserving, and cellulose bleaching. Large scale coal gasification and carbonization plants are another source of chlorinated phenols. Although not normally present in the environment, chlorinated phenols are structurally similar to many plant derived phenolics. It is our hypothesis that bacteria located in swine wastes may also have the ability to degrade chlorinated phenols. Identifying situations (and organisms) in which degradation of pollutants occurs is important field of research. Experimental work was focused on measuring the degradation of seven chlorinated phenols in swine waste using solid-phase micro-extraction (SPME) and gas chromatography(GC). Microbes in the waste perform respiration or fermentation to obtain the energy they need to carry out their life processes. Fermentation is a process in which electrons are transferred from one organic substrate to another and which results in incomplete degradation of organic compounds. Anaerobic respiration is a process in which organic substrates are degraded completely to CO2, but using substances other than oxygen as the terminal electron acceptor (such as Fe(III), NO3- or SO42-). Anaerobic respiration using these alternative electron acceptors provides an easier pathway for degradation of aromatics than fermentation alone. Usually the abundance of these electron acceptors in waste is low since microbes consume them readily and thus they must be added to the mixture. Our work focused on development of methods for the quantification of chlorinated phenols in swine wastes and results of bioremediation research. In this study, chlorophenols were extracted by SPME and analysed by GC. This research project mainly focused on the anaerobic degradation of chlorophenols in swine waste. It was observed that the decreased concentration of the chlorophenols was likely due to partitioning of the chlorophenols to solids, sticking to glass bottles and by bacteria present in the swine waste. In summary, it was observed that by ANOVA and gas production analysis 2,6-dichlorophenol and 2,4,5-trichlorophenol were likely to be degraded by bacteria present in swine waste.

This study presents detailed procedures for site assessment, remedial system design, and optimization of the remedial action operation (RAO) for the petroleum-hydrocarbons contaminated sites. In this work, a petroleum-hydrocarbons contaminated site located in southern Taiwan was selected. Contaminants of concerns (CoCs) from leaking underground storage tanks (USTs) and associated piping included mono-aromatics (e.g., benzene, toluene, ethyl-benzene, xylenes), naphthalene, and aliphatic hydrocarbons. The direct push (DP) technology was adopted for soil gas and soil samples collection. CoCs in the affected subsurface soils and the aquifers were determined by solid-phase micro-extraction/gas chromatography/mass spectrometry and several other analytic instruments. Site investigation via various tests was conducted to evaluate the geology, hydrogeology, bioactivity and free product availability. Based on results of specific site characterization, successful hydraulic containment and substantial recovery of observed free-phase petroleum product were achieved. During the process of field-scale remediation, a test cell which was equipped with a subset of monitoring points and numerous different function active wells (injection well, extraction well, monitoring well, soil gas monitoring probe, reference well and recovery well) was used for remedial system evaluation. A treatment train consisting of the source control treatment and in situ groundwater treatment technology was employed in this study. The former included a vertical containment barrier (i.e., slurry wall) and three pumping wells, whereas the latter included some passive remedial activities. Approximately 87% to 95% decline of the CoCs concentration was observed in those monitor wells after 135 days of operation. Results show that the spilled light non-aqueous phase liquids (LNAPLs) could be efficiently contained and removed using the treatment train system. The treatment train application could be successfully used to reduce the concentrations of CoCs in groundwater to satisfactory levels. Benzene was found to be the only compound in groundwater violating the groundwater pollution control standard. The risk assessment process including hazard identification and exposure assessment was conducted to assess the risk impact of benzene on the human health. Using the methodology approved by ASTM and American Petroleum Institute (API), the baseline carcinogenic risk (9.0E-07) and risk-based groundwater screening level for benzene (0.660 mg/L) were determined. The BIOPLUME III model was also applied to simulate the transport and fate of benzene in site groundwater. Results from this study indicate that site assessment coupled with the treatment train could be used to reduce the concentrations of CoCs in groundwater and soil to satisfactory levels efficiently and effectively.

No description available.

Orientador: Fabio Augusto / Tese (doitorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-11T06:52:57Z (GMT). No. of bitstreams: 1 Silva_AnaClaudiaLemesda.pdf: 2973527 bytes, checksum: 8d640c252ae8364f2e60128332ab484c (MD5) Previous issue date: 2006 / Resumo: O mel é uma das misturas mais complexas de carboidratos produzida pela natureza. É um alimento energético muito importante pelas suas propriedades nutritivas, pelo seu aroma e sabor que dependem fortemente das plantas, flores e condições climáticas presentes na região geográfica onde está localizada a colméia. Não existem metodologias que possibilitem identificação não subjetiva, rápida e confiável da origem floral do mel. O objetivo deste trabalho foi desenvolver uma metodologia que permitisse a identificação da origem floral de méis brasileiros a partir da caracterização química de sua fração de voláteis utilizando micro-extração em fase sólida através do headspace e cromatografia gasosa (HS-SPME-CG). Para o desenvolvimento da metodologia, foram avaliadas 90 amostras de méis brasileiros de vinte origens florais diferentes e variadas procedências geográficas. Onze destas amostras eram unitárias e permitiram apenas um estudo exploratório. Cada tipo de mel apresentou um perfil cromatográfico diferente. Foram identificados potenciais marcadores para os méis de eucalipto (Eucalyptus sp), laranja (Citrus sp), assa-peixe (Vernonia polianthes), cambará (Lantana montevidensis), morrão de candeia (Croton sp) e marmeleiro (Cydonia vulgaris). Os resultados obtidos mostraram que SPME-CG é útil na tipificação de méis e pode eventualmente ser utilizada na sua certificação / Abstract: Honey is one of the most complex mixtures of carbohydrates produced by Nature. It is a very important energetic food for its nutritional properties and for its aroma and flavor that depend strongly on the fauna, flowers and on the climatic conditions in the geographic region where the beehive is located. There are no objective, fast and reliable methodologies for the identification of the floral source of honeys. The objective of this work was to develop a methodology to allow identification of the floral source of Brazilian honeys through characterization of its volatile fraction using headspace solid phase microextraction and gas chromatography (HS-SPME-GC). To develop the methodology, 90 samples of Brazilian honeys of twenty different botanical sources and several geographic locations were employed. Eleven honey types had just one sample, allowing only exploratory studies. Different chromatographic profiles were obtained for honeys from different floral sources. Potential chemical markers were identified for the honeys of eucaliptus (Eucalyptus sp), orange (Citrus sp), assa-peixe (Vernonia polianthes), lantana (Lantana montevidensis), morrão of candeia (Croton sp) and quince (Cydonia vulgaris). The results obtained showed that SPME-GC is useful to identify the floral origin of honey and may eventually be used for its certification / Tese (doitorado) - Universidad / Quimica Analitica / Doutor em Ciências

Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-05-23T19:48:50Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Aline L. C. F. Ribeiro.pdf: 906747 bytes, checksum: c41283b56c0e807e3ab0268c6781aed2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-05-23T19:49:08Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Aline L. C. F. Ribeiro.pdf: 906747 bytes, checksum: c41283b56c0e807e3ab0268c6781aed2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-05-23T19:49:25Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Aline L. C. F. Ribeiro.pdf: 906747 bytes, checksum: c41283b56c0e807e3ab0268c6781aed2 (MD5) / Made available in DSpace on 2017-05-23T19:49:25Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Aline L. C. F. Ribeiro.pdf: 906747 bytes, checksum: c41283b56c0e807e3ab0268c6781aed2 (MD5) Previous issue date: 2015-04-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The need to identify the volatile composition of food is growing every year, mainly driven by the industry. The volatile compounds present in food is very important because they are responsible for their characteristic aroma, which in turn contributes to the taste and consequently to the attraction for the food. The attractive taste of tropical fruits is increasing the consumption of these fruits worldwide, and hence the aroma and flavor of these fruits are getting attention of the industry. Considering this growing interest and the fact that the aroma of most amazonian fruits have not yet been studied, the aim of this study was the characterization of the aroma of three Amazon edible fruits consumed in Manaus region: banana pacovan (Musa paradisiaca L), cajarana (Spondias dulcis Park) and cubiu (Solanum sessiliflorum Dunal). The volatile compounds were extracted by Headspace Solid Phase Microextraction technique and the components were separated and identified by high resolution gas chromatography coupled to mass spectrometry. Two types of commercial SPME fibers were used, CAR-PDMS and PDMS, to compare their efficiency. The extraction capability for each fiber has varied, PDMS fiber was able to extract more components for banana and cubiu, whereas CAR-PDMS for cajarana. Alcohols, aldehydes and esthers were identified in all three fruits, and esthers were more present in cubiu. Terpenes were identified solely in cajarana and carboxylic acids were present only in banana pacova aroma. / A necessidade do conhecimento da composição dos voláteis em alimentos vem crescendo a cada ano, principalmente impulsionada pela indústria. As substâncias voláteis presentes em um alimento são importantes, pois são elas que conferem o seu aroma característico, que por sua vez contribui para o sabor e consequentemente pela atração pelo alimento. O sabor atrativo das frutas tropicais está estimulando o consumo destas frutas em todo o mundo e, devido a isso, o aroma e sabor destes frutos vêm chamando a atenção das indústrias, demonstrando o interesse na caracterização de cada uma delas. Tendo em vista esse grande interesse e o fato do aroma da maioria dos frutos exóticos amazônicos não terem sido estudados ainda, este trabalho teve como objetivo a caracterização do aroma de três frutos comestíveis adquiridos na região de Manaus: banana pacovan (Musa paradisiaca L), cajarana (Spondias dulcis Park) e cubiu (Solanum sessiliflorum Dunal). Os componentes voláteis foram extraídos utilizando a técnica de microextração em fase sólida por “headspace” e a identificação foi realizada através de análises por cromatografia gasosa de alta resolução acoplada com espectrometria de massas. Para a extração dos voláteis, dois tipos de recobrimento de fibra foram utilizados, CAR-PDMS e PDMS, que são normalmente utilizadas nas análises de voláteis. Os resultados obtidos para análise dos aromas de todos os frutos estudados mostraram que a quantidade de substâncias extraídas variou entre as fibras. Os resultados para a banana e para o cubiu apresentaram maior quantidade de componentes extraídos com a fibra PDMS, enquanto para a cajarana foi obtido com a fibra CAR-PDMS. Nos três frutos foram identificadas substâncias voláteis pertencentes à classe de álcoois, aldeídos e ésteres, que foi a principal classe encontrada em todas as análises, principalmente no cubiu. Terpenos foram identificados apenas no aroma da cajarana e ácidos carboxílicos apenas no aroma da banana pacovan.

The exploitation of illicit substances, such as drugs and explosives, is on the rise. Special attention must therefore be considered to reduce the transportation and storage of these illicit substances by improving the capability of detection, even when hidden from view. Although analytical methods of detection for both drugs and explosives have improved over time, biological detectors, such as canines, are still commonly used. In comparison to humans, these canines have a larger number of olfactory receptors and a greater olfactory epithelium surface area, providing them with a more enhanced olfaction than that of humans. The premise for the detection of illicit drugs and explosives is based on the premise that these substances though hidden, will emit volatile organic compounds (VOCs). These VOCs are not often the parent drug or explosive, they are essentially a chemical associated with the source and provide a reliable indication of the illicit substance. Previous successful research has been conducted on the identification of the active odors present in the headspace of cocaine, methamphetamine, and MDMA but instead for marijuana and heroin there have been minimum success. Thus, in the present research a method using headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS) was optimized to identify the VOCs makeup of heroin and marijuana to further identify the active odor compound(s) responsible for the alert response of biological detectors (canines). A mixture of acetic acid and acetylsalicylic acid was identified as target odor mimic for heroin by certified detector canines, while a mixture of limonene and caryophyllene was recognized as odor mimic for marijuana by conducting ORTs. The training aids developed successfully mimic the scent of the actual illicit substance and can be used to improve the capabilities of both drug and explosive detection canines. Additionally, as growing threat of improvised explosives has created a worldwide concern and emphasized the requirement of a greater spectra of canine training aids that covers the complete range of explosives available, a new approach for the creation of training aids for IEDs have been evaluated. The use of a dynamic collection system have proved to be an option to develop fast and reliable canine training aids for IEDs.