The acid which is analogous to the next member of the diphenylpolyenes, 1,4-diphenylbutadiene, is muconic acid. This acid has been chosen to be investigated in an effort to isolate all the stereoisomers of a set containing more than two isomers.

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Creation of electronic materials for chemistry education Bc. Petra Váňová Faculty of Science, Charles University in Prague, 2014 The theme of my thesis is formation of educational instruments/tools for distance education and e-learning which at the same time can be inspirational for teachers of present learning. The theoretical section elaborates on the problems of distance education and e-learning. Furthermore, it describes Moodle, the system for teaching management. For the purpose of the applied section two teaching units were created during the class of Didactics of Organic Chemistry (MC280P06) at Department of Teaching and Didactics of Chemistry, Faculty of Science, Charles University in Prague. The two units focus on the problematic of carboxylic acids and their derivatives. Beside the information about these topics, the contents of the teaching units should provide the students with an insight into modern study tools which increase the effectiveness of distance education as well as present learning. The teaching units are supplemented by study texts, Power Point presentations, handouts with key answers, projects/designs of chemical experiments applying theoretical knowledge to practical level, and a test designed for verifying the improvement of the course participants. The study tools were...

This project studied the biodegradation of a plasticizer, di-(2-ethylhexyl) adipate (DEHA), by two mammalian cell lines, HepG2 and WIF-B, in vitro . An MTT assay showed that DEHA had a toxic effect on both cell lines. Despite this, both hepatocyte cell lines successfully degraded the plasticizer. Metabolites were identified and quantified by gas chromatography. HepG2 cells showed minimal alcohol dehydrogense activity and this resulted in the accumulation of 2-ethylhexanol. WIF-B cells were able to breakdown the alcohol and produced 2-ethylhexanoic acid. It is important to note that an enzyme was essential for this step in the degradation of the plasticizer, as this proves that it was biodegradation and not physical degradation. By comparing the metabolites formed and the order of their appearance, the degradation pathway in these mammalian cells was found to be similar to the established degradation pathways for bacteria, fungi and yeast.

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published_or_final_version / Biological Sciences / Master / Master of Philosophy

VLE data is essential for the design and optimisation of industrial separation processes. Carboxylic acids are of significant interest because of their importance in both industrial and biological processes. Carboxylic acids are used as raw materials for a wide range of products, which include soaps , detergents, nylon , biodegradable plastics, medical drugs and food additives, They are also used both as solvents and as additives and co solvents under a wide range of conditions. Carboxylic acids exhibit strong self and cross -association through hydrogen bonds in both liquid and vapour phases. A thorough understanding of how these molecules interact both with themselves and with other solvents becomes necessary if existing processes may be optimised and new processes developed. Vapour-liquid equilibrium (VLE) data were measured for carboxylic acid systems ranging from C3 to C6• New vapour-liquid equilibrium data were measured for the following binary carboxylic acid systems: • Propionic acid + Hexanoic acid at 20 kPa, 403.15 K, 408.15 K and 413.15 K. • Isobutyric acid + Hexanoic acids at 20 kPa, 413.15 K and 423.15 K. • Valerie acid + Hexanoic acid at 15 kPa, 423 .15 K and 433.15 K. • Hexanoic acid + Heptanoic acid at 10 kPa and 443.15 K. A highly refined dynamic VLE Still by Raal (Raal and Muhlbauer [1998]) was used to undertake the VLE measurements. The still was operated either isothermally or isobarically using a computer control scheme. The isobaric and isothermal control was measured to be ±0.03 kPa and ±0.02 K respectively. The experimental procedure was verified with the highly volatile cyclohexane (l) + ethanol (2) system. The cyclohexane (l) + ethanol (2) measured VLE data was found to be in good agreement with that of Joseph (2001) and passed both the direct test and point test for thermodynamic consistency. A high degree of confidence was then placed on the equipment set-up and experimental procedure, as well as the new carboxylic acids VLE data . The VLE data for all the systems measured were modelled. Two data reduction methods were used: I. The combined ( r- ¢ ) method u. The direct method (¢ - ¢ ) method. In the combined method, the vapour phase non-idea lity was corrected using the Pitzer-Curl (1957) correlation and the Hayden and O' Connell (1975) chemical theory approach. Three liquid phase activity coefficient models were used namely the Wilson, NRTL, and UNIQUAC equations. The Peng-Robinson equation of state (Peng and Robinson [1976]) in combination with the Twu and Coon mixin g rule was used in the direct method. Thermodynamic consistency tests were done on all the systems measured. The point test (Van Ness et a!. [1973]) and the direct test Van Ness ([ 1995]) were used for consistency tests . The direct test could not be carried out on the carboxylic acids data because of the model's inability to adequately characterise the experimental activity coefficients. Generally the models fitted the data well but failed to accurately predict the "S" shape of the carboxylic acids phase diagrams. Considerable work still exists for further investigation into carboxylic acids. Currently, many experimentalists are working in this area . Penget a!. (2004) present ed their progress on developing an equation of state incorporating chemical theory to specifically handle carboxylic acids at the ICCT conference in Beijing, 2004. Raal and Clifford (University of Kwa-Zulu Natal, Thermodynamics Research Unit) are currently developing activity coefficient models incorporating chemical theory for a binary mixture of carboxylic acids. This work is part of the continuing research to under stand the phase behaviour of carboxylic acids. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2005.

Contrairement aux effluents aqueux issus du procédé PUREX, les effluents issus des procédés de séparation poussée actuellement en développement pour séparer les actinides mineurs contiennent des réactifs organiques en quantité importante. Afin de minimiser l'impact de ces composés sur les étapes en aval du procédé et pour respecter les normes de rejet, la destruction de ces composés est indispensable. De par des conditions opératoires et de sûreté adaptées au domaine du nucléaire, la voie sonochimique apparaît comme une solution très prometteuse pour l'élimination des espèces organiques. La propagation d'une onde ultrasonore dans un milieu liquide se traduit par l'apparition de bulles de cavitation qui vont croître et imploser, engendrant ainsi des conditions locales de température et pression extrêmes. Chaque bulle de cavitation peut être alors considérée comme un microréacteur à haute température et haute pression capable de détruire, sans ajout de réactifs spécifiques, les molécules organiques. Les premières études portant sur l'influence de la fréquence ultrasonore sur la sonolyse et la sonoluminescence de l'acide formique ont montré que la dégradation de l'acide formique se déroule à l'interface liquide/bulle quelle que soit la fréquence ultrasonore. La différence notable entre les ultrasons basse et haute fréquence réside principalement dans l'initiation de réactions secondaires observées seulement entre 200 et 1057 kHz. Malgré une activité sonochimique bien plus importante à haute fréquence, l'utilisation des ultrasons seuls pour traiter les effluents issus des procédés de séparation avancée ne peut être envisagée de par la concentration élevée en acides carboxyliques. Afin d'augmenter l'efficacité des réactions sonochimiques, l'ajout de catalyseurs à base de platine supporté a donc été étudié. Dans ces conditions, il s'avère que le couplage ultrasons/catalyseurs permet une augmentation considérable des cinétiques de dégradation des acides carboxyliques. / Unlike aqueous effluents from the PUREX process, aqueous effluents from advanced separation processes developed to separate the minor actinides (Am, Cm) contain organic reagents in large amounts. To minimize the impact of these organic compounds on the next steps of the process, and to respect standard discharges, it is necessary to develop new techniques of degradation of organic compounds. Sonochemistry appears as a very promising solution to eliminate organic species in aqueous nuclear effluents. Indeed, the propagation of an ultrasonic wave in a liquid medium induces the appearance of cavitation bubbles which will quickly grow and implode, causing local conditions and extreme temperatures and pressures. Each cavitation bubble can then be considered as a microreactor at high temperature and high pressure able to destroy organic molecules without the addition of specific reagents. The first studies on the effect of ultrasonic frequency on sonoluminescence and sonolysis of formic acid have shown that the degradation of formic acid occurs at the bubble/liquid interface. The most striking difference between low-frequency and high-frequency ultrasound is that the sonolysis of HCOOH at high ultrasonic frequencies initiates secondary reactions not observed at 20 kHz. However, despite a much higher sonochemical activity at high frequency, highly concentrated carboxylic acids in the aqueous effluents from advanced separation processes cannot be destroyed by ultrasound alone. To increase the efficiency of sonochemical reactions, the addition of supported platinum catalysts has been studied. In these conditions, an increase of the kinetics of destruction of carboxylic acids such as oxalic acid is observed.

O crescimento excessivo da frota veicular mundial tem feito com que milhares de toneladas de poluentes sejam lançadas na atmosfera diariamente em todo o globo, no Brasil a frota de veículos atingiu aproximadamente 54 milhões de unidades, e tem aumentado significativamente em vários estados, segundo o DETRAN (Departamento Estadual de Transito de São Paulo) o estado conta hoje com aproximadamente 19,5 milhões de veículos, 6,5 milhões só na capital, onde são emplacados aproximadamente mil veículos por dia, este crescimento tem causado episódios críticos de poluição do ar nos centros urbanos. Dentre os poluentes lançados na atmosfera de origem veicular, encontram-se os aldeídos e os ácidos carboxílicos, (objetos de estudo deste trabalho), essas substâncias são de suma importância para saúde humana, e participam nas reações fotoquímicas de formação de ozônio na baixa troposfera. Desde a implantação do PROCONVE (Programa de Controle de Poluição do Ar por Veículos Automotores) em 1988, medidas como a redução dos limites de emissão, novas tecnologias na fabricação de veículos automotores, redução da porcentagem de enxofre no diesel, combustíveis renováveis, entre outras, e programas como a Inspeção veicular na cidade de São Paulo criada a partir de 2009, tem sido tomadas visando à constante melhoria na qualidade do ar. Dentre os combustíveis renováveis atualmente utilizados, o biodiesel tem se destacado, tendo em vista o grande consumo de diesel utilizado como fonte de energia no Brasil. Atualmente foram incorporados 2% de biodiesel ao diesel comercial, e antecipando a meta para 2013, possivelmente já no ano de 2010 a porcentagem será de 5%. O objetivo deste trabalho é a caracterização preliminar de aldeídos e ácidos carboxílicos na emissão de veículos do ciclo Otto e do ciclo diesel, utilizando combustíveis fósseis e renováveis. Para a realização deste trabalho foram utilizados três veículos, sendo dois do ciclo Otto e um do ciclo diesel. Os testes foram realizados em dinamômetro de chassis conforme norma ABNT NBR 6601 e ABNT NBR 12026, o método para amostragem dos ácidos carboxílicos foi validado e estabelecido conforme item 6.2 deste trabalho. Nos veículos do ciclo Otto, foram utilizados como combustíveis, a gasolina pura, gasolina com 22% de AEAC (Álcool etílico anidro combustível) e AEHC (álcool etílico hidratado combustível). No veículo do ciclo diesel foram utilizados como combustíveis o diesel comercial com 2% de biodiesel e biodiesel puro de soja. Os resultados obtidos indicaram uma emissão de ácidos carboxílicos 2,5 vezes maior para os testes realizados com os veículos do ciclo Otto, e 5,5 vezes superior para os aldeídos nos resultados dos testes realizados com o veículo do ciclo diesel. A média de todos os resultados obtidos na realização deste trabalho com os veículos do ciclo Otto e do ciclo diesel, utilizando combustíveis fósseis e renováveis, indicaram emissão 3,2 vezes superior dos poluentes pesquisados na utilização de combustíveis renováveis. Estudos com maior número de amostras, e diversificações nas categorias dos veículos devem ser realizados a fim de se detalhar o perfil destes poluentes na emissão veicular com o uso de combustíveis fósseis e renováveis. / The global automotive fleet is emitting thousands of tons of air pollutants daily all over the planet; in Brazil, the domestic fleet reached 54 million vehicles. According to DETRAN (São Paulo state traffic department), the state of São Paulo has 19,5 million vehicles and 6,5 million in São Paulo city, where a thousand new vehicles daily are registered. This fleet growing up is causing critical air pollution situations in metropolitan areas. Among the major automotive air pollutants are aldehydes and carboxylic acids, both are the subject of this study. These substances play an important role for human health and they take place at photochemical reactions generating ozone in low troposphere. Since the beginning of PROCONVE (National Automotive Pollution Control Regulation) in 1988, measures has been taken like emission regulation, development of new automotive technologies, reduction of sulfur content in diesel fuel, renewable fuels and inspection of in use vehicles. Among the fuels from renewable sources currently in use, the biodiesel plays an important role, because diesel is the most used energy source. Currently, with the enforcement of the law number 11097, from January 13rd of 2005, 2% of biodiesel must be added in the commercial diesel and until 2013 this addition will rise to 5%. The subject of this study is the determination of emission profile of aldehydes and carboxylic acids in vehicles powered by Otto and diesel engines using fossil and renewable fuels. In this study were used three vehicles, two of them powered by Otto engines and one sample with diesel engine. The tests were performed in vehicle chassis dynamometer in accordance of the standards ABNT NBR 6601 and ABNT NBR 12026. The method for sampling and evaluation of carboxylic acids was validated and established in article 6.2 of this study. Otto vehicles were tested with 100% gasoline, gasoline plus 22% of anhydrous ethanol and 100% Ethanol. Diesel vehicle were tested with commercial diesel plus 2% biodiesel and 100% soy biodiesel. The results indicates an average 3,2 times higher emission of aldehydes and carboxylic acids when the samples were tested with renewable fuels. Tests with a higher number of samples and variation in vehicle types should be performed in order to provide a more precise profile of these pollutants emission using fossil and renewable fuels.

Yau, Chung Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 55-57). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / Table of Contents --- p.iv / Index of Compounds --- p.v / Chapter 1. --- Introduction / Chapter 1.1 --- Fundamentals of inclusion chemistry --- p.1 / Chapter 1.2 --- Hydrogen bonding in supramolecular chemistry and crystal engineering --- p.3 / Chapter 1.3 --- Hydrogen-bonded rosette system --- p.4 / Chapter 1.4 --- Research plan --- p.7 / Chapter 2. --- Descriptions of crystal structures / Chapter 2.1 --- Supramolecular rosette layer and rosette ribbon constructed from guanidinium cations and hydrogen carbonate dimers /carbonate anions / Chapter 2.1.1 --- (Et4N+)[C(NH2)3+]7(C032-)3[C3N2H2(C00-)2] (1) --- p.11 / Chapter 2.1.2 --- [(n-Bu)4N+]3[C(NH2)3+]4(HC03-)4[H+{C3N2H-(C00-)(C00H)}2] (2) --- p.14 / Chapter 2.1.3 --- [(n-Bu)4N+]2[C(NH2)3+]2(HC03-)2[NCC6H4(C00-)]2 ´Ø 2H20 (3)…… --- p.16 / Chapter 2.1.4 --- "[(n-Bu)4+]8[C(NH2)3+]8(HCO3-)8[4,4'-C12H8(C00-)2]4 ´Ø 8H20 ´″…" --- p.17 / Chapter 2.2 --- Channel- and layer-type anionic host structures constructed from benzene hexacarboxylic acid and guanidinium cation / Chapter 2.2.1 --- [C6(COO-)6][C(NH2)3]6 ´Ø H20 (5) --- p.20 / Chapter 2.2.2 --- [C6(COOH)3(COO´ؤ)3][C(NH2)3+]3 ´Ø 2H20 (6) --- p.23 / Chapter 2.2.3 --- [(n-Pr)4N+][C6(COOH)5(COO-)] ´Ø 3H20 (7) --- p.27 / Chapter 2.2.4 --- [(n-Bu)4N+]4[C6(COOH)5(COO-)]2[C6(COOH)4(COO-)2]2 [C(NH2)3+]2.8H2O(8) --- p.30 / Chapter 2.2.5 --- (Et4N+)2[C6(COOH)4(COO-)2]2[C(NH2)3+]2 ´Ø 2H20 (9) --- p.35 / Chapter 2.2.6 --- (Me4N+)[C6(COOH)3(COO-)3][C(NH2)3+]2 ´Ø H20 (10) --- p.37 / Chapter 3. --- Summary and discussion / Chapter 3.1 --- Robustness of hydrogen-bonded supramolecular rosette networks --- p.40 / Chapter 3.2 --- Versatile hydrogen bonding modes of guanidinium with mellitate anions --- p.43 / Chapter 4. --- Experimental / Chapter 4.1 --- Preparation methods --- p.48 / Chapter 4.2 --- X-ray crystallography --- p.52 / Chapter 5. --- References --- p.55 / "Appendix A: Tables of atomic coordinates, thermal parameters, bond lengths and angles and hydrogen bonds" --- p.58