The Gaoping (GP) river which has the largest drainage basin and is the second longest river in Taiwan. Highly erodible sedimentary and metamorphic rocks in the drainage basin, coupled with a steep landscape, humid climate, frequent typhoons and earthquakes, provide favorable conditions for bedrock weathering and soil erosion in the GP drainage basin. Its exceptionally high sediment yield and tidal-dominated dispersal system presents a unique case for comparative study. In this study, we collected sediment and soil samples not only from estuary region but also traced up to upper stream areas of the GP drainage. We analyze the content of n-alkanes in the sediments and soils of GP river-sea system, and utilize compositional patterns to discuss the sources and process of transmission of terrigenous organic matter of GP river-sea system. Analyzed results show that the average carbon chain distribution shows same pattern for rocks, riverine and seafloor sediments but is different with soil samples. Hierarchical cluster analysis helps us to distinguish differently compositional patterns of n-alkanes. And the riverine, seafloor and rock samples have high similarity, except for soils. The spatial distribution of the carbon preference index (CPI) and temporal distribution of CPI in cores, show that values are all close to ~1, but not for soils (>2). This result indicates that for the past 150 years, lower CPI values not merely from petroleum pollutions, but also due to thermal mature terrestrial organic matter eroded from bedrock caused by tectonic and climatic events, such as typhoons and earthquakes.

SeaWiFS was collecting ocean color data since 1997. This means chlorophyll-a data for more than ten years. Since, SeaWiFS Chl-a data is validated for Black Sea this data set can be used for analysis. Nevertheless, the data is not gap free due to cloud effect. One of the main objectives of this work is to obtain a gap free, complete Chl-a data set for the Black Sea. For this purpose DINEOF method will be used.

The synthesis of highly ordered carbonaceous materials, including carbon nanofibers, has been the subject of a disparate and burgeoning literature over the past decade. Growth of carbon nanotubes via an atypical catalytic route, the decomposition of halogenated reactants as chlorobenzene (CB) over 10% (w/w) Ni/SiO2 is investigated. The C (carbon) yield and structural order are a function of reaction time and temperature. Greater degree of structural order and C yield is observed from CB relative to benzene, suggesting Cl/catalyst interaction(s) and metal site restructuring. Evaluation of the effect of H2 on C growth from CB reveals that C yield is sensitive to % (v/v) H2 with selectivity maxima at 40% (v/v) H2. Further, C yield is significantly influenced by the nature of the heteroatom substituent on the benzene ring; presence of strong electron withdrawing groups favors C yield and weak electron withdrawing or donating groups favors competing side reactions. The effect of the strong electron withdrawing group, Cl, varies with the chemical structure of the carbon source. Presence of Cl promotes C yield in the case of aromatic and straight chained (aliphatic) compounds whereas it promotes formation of benzene in the case of cyclic (aliphatic) compounds. Results are interpreted in term of substituent/ catalyst interaction and the mechanism of solid C formation. Further, effect of % (v/v) H2 on C growth characteristics varies significantly with the precursor. The C growth characteristics are strongly dependent on the nature of the support used, as demonstrated for the following supports: SiO2, Ta2O5, Al2O3, NaY, activated carbon and graphite at 10% (w/w) Ni loading. Ni/SiO2 results in maximum C yield. Variation in Ni loading significantly influences the C yield; higher loading favors greater C yield. C grown on Ni/NaY was found to be relatively more structured to C obtained on the other supports. EDX analysis of the carbon product was used to assess the possibility of Cl intercalation and it reveals presence of 0.4 at% Cl on carbon grown on Ni/Al2O3.

Thesis (Ph.D)--Biomedical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Murthy, Niren; Committee Member: Bellamkonda, Ravi; Committee Member: Davis, Michael; Committee Member: May, Sheldon; Committee Member: Milam, Valeria. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Carbonyl compounds are of central importance to organic chemistry and their reactions have been described as the ‘backbone of organic synthesis’. Over recent decades, palladium-catalysed C–H carbonylation reactions have emerged as a powerful means of introducing carbonyl motifs to organic molecules. This thesis describes the development of a general C–H carbonylation reaction of secondary aliphatic amines, which provides facile access to synthetically useful β-lactam products. The first part of the thesis explores the scope and limitations of this reaction. Whilst previous C(sp3)–H carbonylation methodologies were restricted to ‘Type F’ secondary aliphatic amines, the reaction described in this thesis was found to be broadly applicable all structural sub-classes of secondary aliphatic amine. Furthermore, the reaction was found to be remarkably tolerant of functional groups, even those that commonly cause issues in palladium-catalysed C–H activation reactions such as heteroaromatics and thioethers. The second part of this thesis investigates the mechanism of this C–H carbonylation reaction. Interestingly, the reaction was found not to proceed via a traditional C–H carbonylation mechanism comprising of C–H activation, 1,1-migratory carbon monoxide insertion and reductive elimination. Instead, a new mechanistic paradigm for palladium-catalysed C–H carbonylation is proposed, which invokes a putative ‘palladium anhydride’ intermediate. A series of DFT calculations and experiments were conducted in order to support this mechanistic proposal. The work described within this PhD thesis was published in Science.

O destino de grande parte da matéria orgânica presente nos oceanos é o sedimento marinho. Essa matéria orgânica, que vai sendo armazenada ao longo dos anos, produz uma reserva única de informações sobre os processos biogeoquímicos ocorridos no passado e como esses processos responderam às mudanças ambientais. Certas moléculas orgânicas são sintetizadas apenas por organismos marinhos ou somente por plantas superiores terrestres. A abundância relativa desses compostos em sedimentos marinhos pode ser usada para determinar a contribuição de matéria orgânica terrestre ou marinha que foi depositada. Outros compostos, cujas fontes naturais são raras ou inexistem, encontrados em sedimentos, refletem a influência antrópica no meio. Há ainda compostos, com origem biológica especifica, cujas estruturas são influenciadas pelo controle enzimático dos organismos que os produzem, que são influenciados pelo meio. Esses compostos, cuja presença pode fornecer evidências inequívocas da sua fonte ou informações sobre condições oceanográficas recebem o nome de marcadores biológicos e são comumentemente abreviados como biomarcadores. Esse trabalho produziu uma metodologia analítica para identificação e quantificação de biomarcadores como os hidrocarbonetos alifáticos, hidrocarbonetos policíclicos aromáticos, esteróis e alquenonas através de uma única extração lipídica. Essa metodologia foi avaliada por diversos critérios analíticos e validada através de materiais de referência e de exercícios de comparação entre laboratórios. A metodologia foi aplicada em um testemunho de sedimento marinho obtido em Cabo Frio. A quantificação das alquenonas nas amostras do testemunho permitiu estimar a variação da temperatura da superfície oceânica ao longo dos anos e correlacioná-la com variações na intensidade da ressurgência, além de permitir verificar como os demais biomarcadores variaram em função da variação da temperatura do meio onde foram sintetizados. / The fate of most organic matter in the oceans is the marine sediment. This preserved organic matter became an unique reservoir of information about the operation of biogeochemical processes in the geological past, and how these processes responded to environmental changes. Some molecules are only synthesized by sea organisms, others only by higher plants. The relative abundance among these compounds in sea sediments can be used to determine the source of the organic matter. Other organic compounds, without natural sources, are an indicative of anthropogenic influence. The marine sediment also can accumulate compounds with the specific biological sources, which structures are influenced by the enzymatic control of the precursor organisms. All of these compounds, which can provide clear evidences of its sources or information about oceanographic conditions, are called biological markers or biomarkers. The present work put out an analytic method to identify and quantify biomarkers like aliphatic hydrocarbons, PAHs, sterols and alkenones with only one lipidic extraction. This method was evaluated by several analytic criteria and validated by reference material and by interlaboratory comparison study. The method was used to analyze a marine sediment core from Cabo Frio. The alkenones quantification in this core allowed not only appreciate changes in the sea surface temperature (SST) along the years and correlate them with changes in the upwelling, but also verify how the other biomarkers responded to SST changes.

Made available in DSpace on 2015-05-14T13:21:31Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 4263861 bytes, checksum: 472da3a76dc69c5a3522a75f167eb64f (MD5) Previous issue date: 2013-06-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work sodium vermiculite (VNa+) was subjected to controlled acid leaching with nitric acid (HNO3) at concentrations of 0.3 and 1.0 mol/dm3, leading to the solids named V0,3 and V1,0. Sodium vermiculite and activated solids interacted covalently with silane 3- chloropropyltrimethoxysilane, forming the solids VNaCl, V0,3Cl and V1,0Cl and subsequently with aliphatic diamines 1,2-ethylene-(en), 1,4-butil- (but) e 1,6-hexildiamine. The Solids were characterized by CHN elemental analysis, X-ray diffraction, absorption spectroscopy in the infrared region, thermogravimetric analysis and zeta potential measurements. The obtained materials were used for adsorption of the drugs amiloride and ranitidine in aqueous solution. The saturation time for the drugs studied was greater than 200 minutes. The kinetic study showed a good fit to the pseudo-second-order kinetics, with linear coefficients around 0.99 and good agreement between the values of qt and qe. The concentration isotherms showed a multilayered adsorption, with a better linearization for the model proposed by Freudlich, whose best anchoring values were found for the solids V0,3en and V1,0en, with values close to 95 mg/g for amiloride and 80 mg/g for ranitidine. The matrices V0,3hex and V1,0hex were efficient systems for drug release. / Neste trabalho, a vermiculita sódica (VNa+) foi submetida à lixiviação ácida controlada utilizando ácido nítrico (HNO3) na concentração 0,3 e 1,0 mol/L, originando os sólidos denominados V0,3 e V1,0. A vermiculita sódica e os sólidos ativados interagiram covalentemente com o silano 3- cloropropiltrimetoxisilano, originando os sólidos VNaCl, V0,3Cl e V1,0Cl e subsequentemente com diaminas alifáticas 1,2-etileno-(en), 1,4-butil- (but) e 1,6-hexildiamina. Os sólidos foram caracterizados por análise elementar de CHN, difração de raios X, espectroscopia de absorção na região do infravermelho, análise termogravimétrica e medidas de potencial zeta. Os materiais obtidos foram utilizados para adsorção dos fármacos amilorida e ranitidina em solução aquosa. O tempo de saturação para os fármacos estudados foi de 200 minutos, sendo que o estudo cinético mostrou um bom ajuste para equação cinética de pseudo-segunda ordem, com coeficientes lineares em torno de 0,99 e uma boa concordância entre os valores de qt e qe. As isotermas de concentração mostraram adsorção em multicamadas, com uma melhor linearização para o modelo proposto por Freudlich, cujos capacidades adsortivas foram encontrados para os sólidos V0,3en e V1,0en, com valores próximos a 95 mg/g para a amilorida e 80 mg/g para a ranitidina. As matrizes V0,3hex e V1,0hex se mostraram eficientes para sistemas de liberação do fármaco.

The market of medicinal plants and herbs such as cilantro (Coriandrum sativum) and stevia (Stevia rebaudiana) has been growing due to the demand of the food, chemical and pharmaceutical industries. Leaves of C. sativum are used by many countries in the preparation of food and in folk medicine. The essential oil from the leaves has potential for use in the food industry as an antimicrobial agent and as a condiment to mask undesirable odors and flavors. Studies were conducted to evaluate the activity of the essential oil of cilantro against Leishmaniasis, and the results showed that the essential oil and its major compounds inhibited the growth of L. donovani in its different forms, indicating potential use of this plant for the production of new drugs against Leishmaniasis. From these results, another study was conducted to evaluate five materials of cilantro, a cultivar and four germplasm accessions from the North American Department of Agriculture regarding the quality of the raw material for the food and pharmaceutical industries. The materials with the highest potential to use were AMES 18596 and PI193770 for producing larger amount of dry biomass and the highest production of major compounds, which are desirable by industries. Stevia is a species with high potential to be consumed by diabetics and obese, it is a source of diterpene glycosides used as natural sweeteners. Sweeteners derived from stevia are ingredients in the production of foods, juices and soft drinks in Asia, Europe and in the Americas. The compounds responsible for the sweetness of stevia leaves are well characterized in the literature. However, good agronomic practices are still poorly studied. Some countries have worked on improving this culture and have achieved cultivars with higher yield. In the area of plant nutrition, calcium is one of the most important nutrients for the production of biomass and stevioside in stevia plants. Thus, a preliminary study was conducted to test the effect of calcium applied in nutrient solution in stevia yield, and stevioside and rebaudioside in hydroponic system. The leaf, stem and shoot biomass yield, by stevia plants were influenced by Ca rates in nutrient solutions and were maximal with 7.0, 5.7, 6.2 mmol L-1 of Ca, respectively. The production of stevioside and rebaudioside A was maximal with addition of 4.0 mmol of Ca L-1. / O mercado de plantas medicinais, condimentares e aromáticas tais como coentro (Coriandrum sativum) e estévia (Stevia rebaudiana) vêm crescendo devido à demanda das indústrias alimentícias, químicas e farmacêuticas. As folhas C. sativum são utilizadas por diversos países no preparo de alimentos e na medicina popular. O óleo essencial das folhas tem potencial para utilização na indústria de alimentos como agente antimicrobiano e como condimento para mascarar cheiros e sabores indesejáveis. Estudos foram realizados para avaliar a atividade do óleo essencial de coentro contra a leishmaniose, e os resultados revelaram que o óleo essencial e seus compostos majoritários inibiram o crescimento L. donovani em suas diferentes formas, indicando potencial de uso dessa planta para a produção de novos medicamentos contra Leishmaniose. A partir desses resultados, outro estudo foi realizado com o objetivo de avaliar cinco materiais de coentro, uma cultivar e quatro acessos do germoplasma do Departamento de Agricultura norte americano quanto à qualidade da matéria prima para as indústrias de alimentos e farmacêuticas. Os materiais variaram entre si quanto à produção de biomassa, acúmulo de nutrientes e produção de aldeídos alifáticos tais como (E)- 2-decenal, (E)- 2-dodecenal. Os materiais que apresentaram maior potencial de uso foram AMES 18596 e PI193770, pois, produziram maior quantidade de massa seca e produção de compostos majoritários, que são os desejáveis pelas indústrias. Quanto à estévia, essa espécie apresenta elevado potencial para ser usado por pessoas diabéticas e obesas, pois é fonte de diterpenos glicosídicos usados como adoçantes naturais. Os adoçantes derivados de estévia são usados na produção de alimentos, sucos e refrigerantes em diversos países asiáticos, europeus e no continente americano. Os compostos responsáveis pelo dulçor das folhas de estévia são bem caracterizados pela literatura, entretanto, as boas práticas agronômicas ainda são pouco estudadas. Alguns países trabalharam no melhoramento dessa cultura e conseguiram alcançar cultivares mais produtivas. Na área de nutrição, o cálcio está entre os nutrientes mais importantes para a produção de esteviosídeo e produção de biomassa de estévia. Assim, um estudo preliminar foi conduzido com o objetivo de estudar o efeito do cálcio aplicado em solução nutritiva na produção de estévia, e de esteviosídeos e rebaudiosídeos, em sistema hidropônico. A produção de folhas, caule e parte aérea por plantas de estévia foi influenciada por níveis de Ca na solução nutritiva e foram máximos com as doses de 7,0, 5,7, 6,2 mmol L-1 de Ca, respectivamente. A produção de esteviosídeo e rebaudiosídeo A foi máxima com a adição de 4,0 mmol L-1 de Ca.

Orientador: Lucia Helena Innocentini Mei / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-03T19:31:20Z (GMT). No. of bitstreams: 1 Talamoni_JoaoRoberto_M.pdf: 3179199 bytes, checksum: 8fe9d391161838e5f0a3bd3360ef2652 (MD5) Previous issue date: 2003 / Resumo: Anualmente, são produzidas cerca de 110 milhões de toneladas de plásticos no mundo, e pelo menos a metade desta quantidade é rapidamente descartada sem qualquer cuidado, permanecendo em aterros e na natureza por décadas, gerando um custo ambiental muito alto. Na tentativa de minimizar este problema, muitos cientistas passaram a investir em pesquisas na tentativa de descobrir materiais que substituam estes plásticos e que ao mesmo tempo sejam ambientalmente amigáveis, ou seja, quando em contato com o solo e em ambientes propícios, estes novos materiais se degradem rapidamente. Muitas linhas de pesquisas trabalham com polímeros de origem natural, outras com síntese microbiológica, porém, uma das linhas de pesquisas mais forte neste sentido é a síntese e modificação de poliésteres alifáticos, que sabidamente possuem boas propriedades de biodegradação. Assim, o objetivo deste trabalho foi sintetizar, caracterizar e modificar um poliéster alifático com boas propriedades de biodegradação. Partiu-se de monômeros conhecidos, como o ácido adípico e o monoetileno glicol, e ainda usou-se outros materiais para tentar melhorar as propriedades dos polímeros sintetizados, como o glicerol e o diisocianato de hexametileno, este último usado para se obter poliésteres-uretanos de massa molar maior, menor cristalinidade e de mais fácil biodegradação. Todas as amostras obtidas foram caracterizadas via medições de suas massas molares por Cromatografia por Permeação em Gel e Viscosidade Intrínseca, e ainda mediuse a efetividade das reações através da Espectroscopia por Infravermelho. Também determinou-se as temperaturas de cristalização e de fusão através da Calorimetria Diferencial Exploratória e a perda de massa através de Análise Termogravimétrica. Ainda, acompanhou-se o processo de biodegradação através de fotos e microscopia ótica. Os resultados obtidos neste trabalho mostraram que a síntese de poliésteres alifáticos requer muitos cuidados para que se obtenha materiais com boas propriedades de aplicação, e que as modificações via isocianato, obtendo-se poliésteres-uretanos, é um caminho bastante interessante para a melhoria destas propriedades, e ainda, pode-se concluir que a síntese destes materiais é bastante promissora para se obter materiais / Abstract: Annually, about 110 millions of tons of plastics are produced around the world, and at least haIf of this amount is wasted speciaIly in landfills, remaining there for decades, causing high1y environmental costs. In order to solve this problem, many scientists are performing researches trying to create new materiaIs with adequate properties to replace these plastics and at the same time, materiaIs that are environmentally mends, and can be degraded when in contact with soil and under adequate conditions. Many researchers are working with natural polymers, others with polymers synthesized through microbiologicaI conditions, and others are working with the synthesis and modification of aIiphatic polyesters, which are known since decades that they are good biodegradable materiaIs. The objective of this work is the synthesis, characterization and modification of aIiphatic polyesters with good biodegradable properties. It was used known monomers for the synthesis, like adipic acid and ethylene glycol, and others materiaIs to improve properties, like glycerol and hexamethylene diisocyanate, this last one was used to obtain a polyester-urethane, with high molecular weight and lower degree of crystallization, improving its ability to degrade. All samples synthesized were characterized by Gel Permeation Chromatography and Intrinsic Viscosity to measure their molecular weight, and the effectiveness of the reactions were followed by Fourier-Transform Infrared Spectroscopy. Melting and Glass Transition temperatures and Crystallization behavior were measured through Differential Scanning Calorimetry. Using Thermogravimetry measurements, the loss of mass of all samples with temperature was measured. The biodegradation process was followed by periodical photos and with Optical Microscopy. The final results showed that the synthesis of aliphatic polyesters need to be carefully carried out to achieve materials with good properties, and the extension of these aliphatic polyesters with isocyanates is a viable way to increase properties of these materials, but it is possible to conc1ude that the synthesis of such materials is a very promising field to have biodegradable materials / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química

In order to explore the N-H stretching region of aliphatic amines, we performed a study of the Raman spectrum of n-propylamine at various concentrations in cyclohexane. Statistical analysis provided evidence of a second symmetric stretching vibration, which we were able to assign to nonhydrogen bonded NH2 groups. To obtain additional evidence on the existence of monomers in n-propylamine and to further study hydrogen bonding and Fermi resonance in aliphatic amines, we extended the investigation to the analysis of the Raman spectrum of this compound over an extended range of temperature in the neat liquid phase. This study corroborated our finding that the peak previously assigned to the symmetric stretching mode of hydrogen bonded amines is actually composed of two bands. Furthermore, trends in both the resolved band parameters and the Fermi resonance analysis were tabulated, allowing one to monitor the change in the N-H valence region with concentration and temperature.