La chimie d'interface du diazonium a progressé au cours des dernières années et s'est pratiquement impliquée dans tous les domaines de la science et technologie des matériaux. L’utilisation des sels de diazonium est justifiée par le fait qu’ils adhèrent aux surfaces avec de fortes énergies de liaison, en particulier sur le carbone sp², ce qui en fait d’excellents agents de couplage pour les polymères aux surfaces. Dans ce contexte, nous avons travaillé sur deux types de nanohybrides de nanotubes de carbone (NTC) : NTC-polytriazole (NTC-PTAz) et NTC-colorant. Le nanohybride NTC-PTAz a été synthétisé par polymérisation « click » en surface. Pour ce faire, les NTCs ont été greffés de groupes 4-azidophényle à partir du sel de diazonium correspondant. Le NTC modifié (NTC-N3) a servi de support pour une polymérisation confinée en surface de type polyaddition générant ainsi le nanohybride NTC-PTAz. Ce matériau a été caractérisé par ATG, XPS, IR et Raman. Ses applications potentielles sont dans le développent d’adsorbants de métaux lourds, l’immobilisation de nanocatalyseurs ou pour le stockage des gaz. La seconde partie de la thèse est plus étoffée et porte sur les nanotubes de carbone greffés de colorants diazotés Rouge Neutre (NR), Azure A (AA) et Rouge Congo (CR). L’analyse fine de ces matériaux a révélé une très forte adhésion des colorants aux NTCs et les couches superficielles ont des épaisseurs de 2 à 6 nm, sont homogènes et continues. Les NTC-colorant ont été incorporés dans des matrices élastomères de type EVA pour la réalisation d’actionneurs opto-thermiques implantés dans des pads pour non-voyant. Dans les matrices EVA, les NTCs greffés de colorants servent à capter la lumière et induire un changement de forme dans le pad qui soit palpable par le non voyant (250 µm). Les matrices EVA renforcées de nos nanotubes greffés de colorants ont été réalisées et testées par analyse mécanique dynamique. Les composites NTC/colorant-EVA sont flexibles et prometteurs pour le développement de nouveaux types des pads tactiles pour les non-voyants. Les nanohybrides NTC-NR ont servi comme capteurs chémo-résistifs pour la reconnaissance moléculaire de l’acétone.Dans une dernière application, le nanohybride CNT-CR a été étudié en tant qu’électrocatalyseur pour l’oxydation directe du méthanol. Des résultats intéressants ont été obtenus avec ces nanohybrides mais des améliorations significatives (rapport 3) des propriétés électrocatalytiques ont été obtenues avec des CNT-CR décorés avec des nanoparticules d'or. Le système électrocatalytique nouvellement conçu pourrait être considéré pour différentes applications prometteuses, notamment les capteurs, les biocapteurs, les catalyseurs hétérogènes pour les piles à combustible. Pour résumer, les nanohybrides à base de CNT nouvellement conçus présentent des performances uniques attribuées à la polyvalence de la chimie d'interface du diazonium pour la fixation efficace de couches moléculaires et macromoléculaires fonctionnelles. Les nanohybrides novateurs servent de blocs de construction pour la conception de matériaux nanocomposites à hautes performances potentiellement utiles dans les nouveaux défis socio-économiques tels que l’environnement, la biomédecine et l’énergie / Diazonium interface chemistry has progressed over the last few years and practically involved in all areas of materials science and engineering. The rationale for employing diazonium salts is that they attach to surfaces with remarkable bond energies, particularly on sp² carbon materials, making them an ideal coupling agent for polymers to surfaces In this context, novel CNT-polytriazole (CNT-PTAz) and CNT-dye nanohybrids were designed and thoroughly characterized. First, CNT-PTAz nanohybrid was prepared by click polymerization: multiwalled carbon nanotubes (CNTs) were modified with azidophenyl groups (CNT-N3) from 4-azidobenzenediazonium precursor and served as nanoscale platform for the surface confined polyaddition. The CNT-PTAz nanohybrid was characterized by TGA, XPS, IR, and Raman. The robust CNT-PTAz is robust and has potential in developing heavy metal adsorbents, nanosupport for catalysts or for gas storage. In the second major part, we grafted CNT with diazotized Neutral red (NR), Azure A (AA) and Congo Red (CR) dyes by simple, spontaneous reaction of the diazonium salts and CNTs in water, at RT. A thorough investigation of the nanohybrids showed that the adhesion is strong (CNT-dye C-C bond energy higher than 150 kJ/mol), and the layer is uniform. These nanohybrids further served to reinforce ethylene-vinyl acetate (EVA) an elastomeric matrix. The reinforced matrix is flexible and serves as optothermal actuators where the grafted dye catches the light to induce mechanical changes in the matrix monitored by dynamic mechanical analysis. CNT/dye-reinforced EVA is a promising flexible composite for developing new types of visual-aid tablet for visually impaired people. The versatile CNT-dye nanohybrids are also unique chemiresistive gas sensors for the molecular recognition of acetone vapours. In a final application, CNT-CR nanohybrid was investigated as an electrocatalyst for the Direct Oxidation of Methanol. Interesting results were obtained with these nanohybrids but significant improvements (3-fold) of the electrocatalytic properties were achieved with CNT-CR decorated with gold nanoparticles. The newly designed electrocatalytic system could be regarded for different promising applications most likely as for sensors, biosensors, heterogeneous catalysts for fuel cells and for nanotechnology To summarize, newly designed CNT-based nanohybrids have unique performances ascribed to the versatility of the diazonium interface chemistry in efficiently attaching functional molecular and macromolecular layers. The novel nanohybrids serve as building blocks for designing high performance nanocomposite materials relevant to challenging timely social economic issues, namely environment, biomedicine and energy

Thesis advisor: Gail Kineke / The Penobscot River Estuary is heavily contaminated with mercury; previous studies indicate maximum mercury concentrations of 4.6 ppm within the Frankfort Flats reach. The transport and trapping of this contaminant is linked to the transport and trapping of fine sediment within the estuary. Hydrographic and flow measurements, coupled with a spatial and temporal characterization of the bottom sediments, were performed during and following the freshet in 2010 to determine the mechanisms driving sediment transport and trapping within the estuary. The Penobscot River likely has a turbidity maximum associated with the landward extent of the salinity intrusion that is positioned over the Frankfort Flats reach during average discharge and tidal conditions. This turbidity maximum may be responsible for a patch of fine sediments in the Frankfort Flats reach in an otherwise coarse-grained bed. Additional transport and trapping of fine sediments within this reach is the result of secondary circulation driven by centripetal acceleration around meanders in the channel. Close proximity of meanders at Frankfort Flats, within ~5 km, creates opposite secondary circulation of magnitude ~0.2 m/s during flood and ebb conditions. / Thesis (BS) — Boston College, 2011. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Geology & Geophysics Honors Program. / Discipline: Earth and Environmental Sciences.

A iodação do sal de mesa é considerada o caminho mais eficiente para controlar os Distúrbios por Deficiência de Iodo. Em países tropicais, o elemento pode ser adicionado na forma de KIO3. Para garantir que os níveis ideais do ânion estejam disponíveis ao consumidor, o controle de qualidade do sal consiste numa estratégia fundamental. Sistemas em fluxo com multicomutação representam uma alternativa versátil para o desenvolvimento de procedimentos simples, rápidos e limpos, minimizando o consumo de reagentes e a geração de resíduos. Nesse contexto, um procedimento analítico utilizando sistema com multicomutação e detecção espectrofotométrica foi desenvolvido para a determinação de iodato em sal de mesa. A reação empregada foi baseada na formação de um composto roxo (540 nm) entre iodato (IO3-) e p-aminofenol (PAP) em meio ácido. O tempo de residência da zona de amostra no percurso analítico foi explorado a fim de favorecer a reação lenta e a frequência de amostragem para a melhoria do desempenho analítico. Foram selecionados 2 pulsos para inserção de amostra, 3 pulsos para reagente (PAP 0,25% (m/v) em HCl 0,025 mol L-1), 7 ciclos de amostragem, 200 pulsos de carregador (água), bolha de ar de 1 s (40 µL), reator de 70 cm (3 mm d.i.) e parada de fluxo de 480 s. Resposta linear foi observada entre 2,28x10-5 e 3,65x10-4 mol L-1, descrita pela equação A = 0,2443 + 2030 C, r = 0,997. Limite de detecção (99,7% de confiança), coeficiente de variação (n = 20) e frequência de amostragem foram estimados em 8,2x10-6 mol L-1, 0,42% e 70 determinações por hora, respectivamente. Houve consumo de 1,05 mg de PAP e geração de 0,70 mL de resíduos por determinação. As principais espécies concomitantes presentes na amostra não interferiram na determinação de iodato em concentrações até 8 vezes maiores que as usualmente encontradas. Estudos de adição e recuperação de iodato foram realizados pelo procedimento proposto, obtendo porcentagens de recuperação entre 88 e 104%. O procedimento analítico desenvolvido apresenta sensibilidade adequada para a determinação de iodato em amostra de sal de mesa e elevada frequência de amostragem quando comparado com procedimentos descritos na literatura / Table salt iodization is considered the most efficient way to control iodine-deficiency disorders. In tropical countries, the element can be added as KIO3. To ensure that ideal amounts of this anion are available to consumers, the quality control of iodized salt is fundamental strategy. Multicommuted flow systems represent a versatile alternative to the development of simple, fast and clean procedure, minimizing reagent consumption and waste generation. In this context, an analytical procedure using a multicommuted system and spectrophotometric detection was developed for determination of iodate in table salts. The chemical reaction was based on the formation of purple compound (540 nm) between iodate (IO3-) and p-aminophenol (PAP) in acidic medium. The sample residence time in the analytical path was explored in order to further the slow chemical reaction and the sampling rate for the improvement of the system analytical performance. Optimized conditions were 2 sample pulses, 3 reagent pulses (PAP 0.25% (w/v) in HCl 0.025 mol L-1) in 7 sampling cycles, 200 carrier pulses (water), 1 s air bubble (40 µL), a 70-cm long reactor coil (3 mm i.d.) and the flow was stopped for 480 s. A linear response was observed between 2.28x10-5 and 3.65x10-4 mol L-1 iodate, described by the equation A = 0.2443 + 2030 C, r = 0.997. Detection limit (99.7% confidence level), coefficient of variation (n = 20) and sampling rate were 8.2x10-6 mol L-1, 0.42% and 70 determination per hour, respectively. Only 1.05 mg of PAP was consumed and 0.70 mL of waste was generated per determination. Usual concomitant species found in table salts did not cause significant interference in concentrations up to 8-fold higher than those expected. Recoveries between 88 and 104% were obtained for iodate spiked samples. The developed analytical procedure presented adequate sensitivity for the determination of iodate in table salts sample and higher sampling rate compared to literature procedures

O presente trabalho traz uma análise sobre os resultados econômico-financeiros que podem ser esperados com a produção de petróleo em reservas localizadas na área do pré-sal no Brasil. Para isso, desenvolve um modelo de simulação da produção e análise econômico-financeira denominado modelo CAMPOS. Inicialmente, o modelo simula a produção que pode ser esperada em cada um dos campos analisados e, a partir desse resultado, calcula as receitas que podem ser esperadas pelos diferentes stakeholders (empresas e poder público) sob distintos cenários de preços do barril de petróleo, de investimentos e de regimes regulatórios. Com relação aos regimes regulatórios, as receitas são simuladas tanto para aqueles vigentes hoje no país (concessões, partilha de produção, cessão onerosa e cessão onerosa com partilha de produção para volumes excedentes), como para outras formas regulatórias, como o regime de serviços. Um dos resultados dos cenários econômico-financeiros são os preços de equilíbrio para cada um dos campos e em cada regime regulatório, indicando o valor mínimo do barril de petróleo que torna a produção no campo viável da perspectiva financeira. Também, são apresentadas todas as receitas governamentais que podem ser esperadas, além de uma estimativa de recursos que devem ir para as áreas da saúde e da educação em decorrência da cobrança de royalties. De modo geral, tem-se que o regime de partilha de produção não foi o que demonstrou trazer mais receitas ao poder público, considerando as premissas com as quais foi simulado neste trabalho, ou seja, com base nas regras e dinâmica de definição da participação da União no óleo produzido conforme o resultado do leilão para o campo de Libra. Isso parece contraditório, já que o regime de partilha de produção foi instaurado no país em 2010 em um contexto de debate nacional acerca das possibilidades de aumentar a parcela governamental sobre a produção em áreas do pré-sal. O regime que mostrou trazer maior receita ao poder público é o regime de serviços, pelo qual a União é investidora e detentora das reservas e dos resultados da produção. No entanto, esse regime não é aplicado no país. Por isso, medidas que aproximem o regime de partilha de produção vigente hoje às regras do regime de serviços concebido, considerando as possibilidades existentes na legislação, tendem a aumentar o valor das receitas governamentais. Após o regime de serviços, aquele que apresenta maior parcela governamental é o regime de concessões, já que a soma das participações especiais e dos royalties normalmente ultrapassa a soma da porcentagem da União sobre o excedente em óleo e royalties no regime de partilha de produção, considerando as premissas de simulação adotadas. Apenas em campos com grandes reservas e quando o preço do barril de petróleo é mais elevado, as receitas governamentais no regime de partilha ultrapassam as do regime de concessões. Assim, conclui-se que para que o regime de partilha de produção traga mais receitas ao poder público, deve haver mecanismos que garantam que a definição da porcentagem da União sobre o excedente em óleo seja mais elevada do que aquela que se verificou no caso do leilão para o campo de Libra, por exemplo. / This research brings an analysis of the economic and financial results that can be expected with the oil production in the pre-salt area in Brazil. The analysis is based in a simulation model called CAMPOS developed within the research framework. Initially, the model simulates the oil production that can be expected in each of the oil fields and from this calculates the revenues that can be expected by different stakeholders (companies and public authorities) under different scenarios for oil prices, investments and regulatory regimes. With respect to regulatory regimes, revenues are simulated both for those currently in force in the country (concession, production sharing and onerous transfer of rights), and for other regulatory forms such as the service regimes. One of the outcomes is the break-even prices for each oil field and for each regulatory regime, indicating the minimum oil price that makes the production viable from the financial perspective. This research also brings all the government takes that can be expected, as well as an estimate of financial resources that may go to health and education sectors as a result of the collection of royalties. In general, the production sharing regime hasnt proved to be the one bringing more revenues to the government, considering the premisses with which it was simulated in this work, that is, based on the rules defined for the Libra field. This seems contradictory, since the production sharing regime was introduced in the country in 2010 in a context of national debate about the possibilities of increasing the government takes coming from oil production in pre-salt areas. The regime that has shown to bring more revenues to the government is the service regime, by which the State is an investor and holds the reserves and oil properties. However, this regime does not apply in the country considering the current legislation in force. Therefore, measures that approximate the production sharing regime currently in force to the rules of the designed service regime, considering the possibilities of the legislation, tend to increase the value of government takes. Considering the premises adopted in the simulations, following the service regime the one showing the largest government take is the concessions scheme. In this case the amount collected in the form of special participations and royalties usually exceeds the amount collected in the production sharing regime in the form of government share in the oil production and royalties. Only in fields with large reserves and when the oil price is high, government takes in the production sharing regime exceeds those of the concessions regime. It follows that in order for the production sharing regime to bring more revenues to the public interest, there must be mechanisms to ensure that the government share in the oil produced is higher than that stablished in the case of the Libra field.

Plant cell wall is critical for the regulation of cell shape, cell growth, and responses to abiotic stress and pathogen infection. The plant cell wall is composed of several monosaccharides including glucose, galactose, mannose, xylose, fucose, rhamnose, and arabinose. Arabinose-containing polymers account for ~20 % of the total cell wall saccharides in rice and Arabidopsis. Arabinose is a plant-specific monosaccharide that is required for the decoration of several cell wall polysaccharides, including rhamnogalacturonan I (RGI)-arabinan, arabinoxylan, and rhamnogalacturonan II (RGII). Arabinose is also involved in the modification of some cell wall glycoproteins, including arabinogalactan-proteins (AGPs), extensins, and leucine-rich repeat extensin (LRX) proteins. In addition, arabinose is conjugated to signaling peptides like CLAVATA3 and some cytoplasmic arabinosylated flavonols, such as quercetin 3-O-l-arabinoside and myricetin. The only known enzyme in the final step of the arabinose de novo biosynthesis pathway is the Golgi-localized UDP-D-xylose 4-epimerase (MUR4), which converts UDP-xylose to UDP-arabinose. There is a 50% reduction of cell wall arabinose in mur4 mutant, indicating that other enzymes may also be involved in the de novo biosynthesis pathway. Under salt stress, mur4 mutant plants exhibit reduced root elongation and abnormal cell-cell adhesion. The roles of three MUR4 paralogs, MURL, DUR, and MEE25, in arabinose biosynthesis and salt stress tolerance are described. Data are also shown regarding the importance of AGPs in salt tolerance. Analysis of higher order mutants of mur4 with its three paralogs reveals that the three proteins also contribute to the biosynthesis of UDP-Ara and are critical for root elongation. The salt-hypersensitivity of the mur4 mutant is rescued by exogenous arabinose or gum Arabic (a commercial AGP product). Taken together, my work reveals the importance of arabinose metabolism in salt stress tolerance and provides new insights into the enzymes involved in UDP-Ara biosynthesis in plants. Plants have evolved cell-wall integrity sensing and signaling pathways to maintain cell-wall homeostasis in response to stress conditions, but the cellular components involved in the perception and transduction of cell-wall signals are largely unknown. I found that the cell wall-localized leucine-rich repeat extensins (LRX) 3/4/5 interact with RAPID ALKALINIZATION FACTOR (RALF) peptides RALF22/23 to transduce cell wall signals. Mature RALF22/23 peptides convey signals to the plasma membrane-localized FERONIA (FER) to induce intracellular stress responses. The lrx345 and fer mutants and RALF22/23 overexpressing transgenic plants display similar phenotypes, including retarded growth and increased sensitivity to salt stress. These results suggest that LRX3/4/5, RALF22/23, and FER function as a module to regulate plant growth and salt stress tolerance. Further analyses show that the LRXs-RALF-FER module negatively regulates the accumulation of the phytohormones jasmonic acid (JA), salicylic acid (SA), and abscisic acid (ABA), and the simultaneous over-accumulation of these stress hormones can be detrimental to plants. Based on genetic and biochemical data, we propose that salt-induced perturbations of the cell wall may be sensed by the LRXs, triggering the release of RALF peptides in the extracellular space; these peptides are then perceived by FER, inducing its internalization and down-regulating its function as part of a homeostatic mechanism to halt growth and to acclimate to salt stress through the activation of ABA, JA and SA signaling. Taken together, my work offers valuable insights into how salt stress is sensed in the apoplast by the LRXs-RALFs-FER signaling module, which subsequently modulates hormone signaling to establish a homeostatic mechanism coordinating growth and stress responses. In brief, my study contributes to the understanding of the role of MUR4 family of enzymes in plant arabinose biosynthesis and the role of arabinose-containing macromolecules in salt stress sensing and adaptation.<br>

Plant interactions (e.g., competition, facilitation) are critical drivers in community development and structure. The Stress Gradient Hypothesis (SGH) provides a predictive framework for how plant species interactions vary inversely across an environmental stress gradient, predicting that facilitation is stronger with increasing levels of stress. The SGH has been supported in numerous ecosystems and across a variety of stress gradients, but recent research has demonstrated contradictory results. These discrepancies have led to SGH revisions that expand its conceptual framework by incorporating additional factors, such as other stressor types and variations in species life history strategies. In this dissertation, I examine a further modification of the SGH by proposing and testing a Multiple Stress Gradient Hypothesis (MSGH) that considers how plant interactions vary along a continuous gradient of two co-occurring stressors using mangrove and salt marsh communities as a case study. In Chapter 1, I outline the predictive framework of a MSGH, by creating a series of predictions of species interactions. The components of the MSGH predict that stressors of similar types (e.g., resource and nonresource) will have similar effects and be additive. On the other hand, varying species life history strategies and life stages will lead to extremes of plant interactions. In Chapter 2, I performed a series of experiments to test the various components of the MSGH. In Chapter 3, I performed a large-scale observational study to test whether multiple co-occurring stressors altered the cumulative effects on plant interactions, and if these stressors should be grouped (e.g., resource and non-resource, abiotic and biotic, etc.) to enhance predictability. From a series of studies conducted herein, I concluded that co-occurring stressors are important factors that control complex species interactions as shown in my MSGH modeling approach. Further, future theories need to incorporate species-specific and stressor specific grouping when modeling how species interactions shape communities. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2013.

Advances in molecular-simulation methods allow for ever larger systems of particles to be studied and on longer timescales. Calculations are reaching such a scale that they can be used to address a vast range of key questions across chemistry, physics, and engineering. In this work, molecular dynamics and Monte Carlo simulations are employed to address two key areas: the structure and dynamics of simple aqueous ionic salt solutions at high concentrations; and the structure, dynamics, and phase behaviour of dipolar fluids (such as colloidal ferrofluids). The first part of the work begins with a study of the structure and dynamics in metastable, supersaturated, aqueous solutions of potassium chloride, and the possible relevance of these to the phenomenon of non-photochemical laser-induced nucleation (NPLIN). It is thought that the potassium and chloride ions form long-lived, amorphous clusters that may, under the influence of nanosecond laser pulses, undergo structural reorganisation to form post-critical crystal nuclei. It is found that spontaneous nucleation does not occur on the simulation timescale, but that amorphous clusters do form with cluster lifetimes comparable to those of the shortest laser pulses that can be used in NPLIN ( 100 picoseconds). Next, an alternative scenario for NPLIN involving rapid laser heating of impurity particles is examined by simulating heated carbon nanoparticles in saturated aqueous solutions of sodium chloride. The concentration at which an aqueous sodium chloride solution first crystallises on the simulation timescale is determined. A spherical carbon impurity is then added to a system with concentration close to, but lower than, the concentration at which crystallisation occurs on the simulation timescale. The effects that adding, and heating, this impurity has on the structure of this near-crystallising system are then observed. The second part of the work discusses model dipolar fluids, of direct relevance to colloidal ferrofluids (suspensions of magnetised nanoparticles in simple carrier liquids). The two-body, dipole-dipole interaction is long-ranged and anisotropic, and it is computationally expensive to handle in molecular simulations. Here a new method is proposed that relies on a formal mapping between the partition function of a dipolar fluid and that of a hypothetical fluid with many-body, short-ranged, isotropic interactions. Only the leading-order two-body interactions (akin to the van der Waals attraction) and three-body interactions (corresponding to the Axilrod-Teller potential) are retained. It is shown that this simple model is sufficient to reproduce the characteristic particle chaining and the associated disappearance of the vapour-liquid phase transition of dipolar fluids. Finally, the dynamical response of ferrofluids to oscillating magnetic fields (the dynamic magnetic susceptibility [DMS]) is studied. The DMS of ferrofluids, predicted by a new theory that takes into account the leading-order effects of dipole-dipole interactions, are critically compared to those found using Brownian-dynamics simulations of monodisperse systems of dipolar particles. This new theory is found to provide more accurate predictions of the DMS than previous theories, with the DMS predicted to a high degree of accuracy for systems with dipolar coupling strength in the experimentally achievable region.

Yeung Chi Ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 123-134). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledges --- p.iv / Table of contents --- p.v / List of Tables --- p.vii / List of Figures --- p.ix / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Mode of reproduction of Mikania micrantha / Chapter 2.1 --- Introduction --- p.15 / Chapter 2.2 --- Literature review --- p.16 / Chapter 2.3 --- Materials and methods --- p.19 / Chapter 2.4 --- Results --- p.23 / Chapter 2.5 --- Discussions --- p.35 / Chapter Chapter 3: --- Effect of sodium chloride on seed germination of Mikania micrantha / Chapter 3.1 --- Introduction --- p.42 / Chapter 3.2 --- Materials and methods --- p.44 / Chapter 3.3 --- Results --- p.48 / Chapter 3.4 --- Discussions --- p.58 / Chapter Chapter 4: --- Sodium chloride as a herbicide for Mikania Micrantha in Mai Po Marshes / Chapter 4.1 --- Introduction --- p.60 / Chapter 4.2 --- Literature Review --- p.61 / Chapter 4.3 --- Materials and methods --- p.74 / Chapter 4.4 --- Results --- p.80 / Chapter 4.5 --- Discussions --- p.113 / Chapter Chapter 5: --- Conclusions --- p.118 / References --- p.123

A novel process for single-pot conversion of biomass to biofuels was developed called the molten salt catalytic pyrolysis (MSCP) method. The proposed single-pot MSCP process proved to be an inherently more efficient and cost-effective methodology for converting lignocellulosic biomass. In this study, several parameters that affect yield of bio-oil were investigated including carrier gas flow rate; pyrolysis temperature; feed particle size; varying types of molten salt and catalysts. Use of molten salt as the reaction medium offered higher liquid yield and experiments containing ZnCl2 showed higher yield than other chloride salts. The highest yield of bio-oil was up to 66% obtained in a ZnCl2-KCl-LiCl ternary molten salt system compared with 32.2% at the same condition without molten salts. In addition, the effect of molten salt on the composition of bio-oil was also studied. It was observed that molten salt narrowed the product distribution of bio-oil with furfural and acetic acid as the only two main components in the liquid with the exception of water. Finally, a thermogravimetric kinetic study on the pyrolysis of biomass in MSCP was conducted.

In recognition of the shortcomings inherent to the operating temperature ranges of current fuel cell systems, namely the“temperature gap" between 200C and 600C, an effort to develop an intermediate-temperature molten-salt electrolyte fuel cell (IT-MSFC) was undertaken. In this type of fuel cell, the molten salt electrolyte is supported on a porous support, in a planar or other geometry similar to that used in existing fuel cell technologies, such as phosphoric acid fuel cell (PAFC) and molten carbonate fuel cells (MCFC). Such a fuel cell using a molten hydroxide electrolyte and Pt/C catalyst was constructed and tested using hydrogen and oxygen as fuel. The performance was comparable to that which has been obtained from PEM fuel cells at the low end of the voltage range, reaching 950ma/cm2 at 0.4 V in the highest performing test. Performance was superior to PEM fuel cells at the high end of the voltage range, due to the more favorable kinetics at the higher temperatures, with an open circuit voltage (OCV) of 1.0 V with a linear performance curve between 1.0 V and 0.6 V, which is characteristic of fuel cells with low kinetic overpotentials. Longevity of the fuel cell was very poor, however a number of experiments were undertaken to improve it, enabling extension of operating life from 5 minutes to 30 minutes, which is still far too low for practical use. The key problem was identified as electrolyte retention by the support matrix and possible degradation of the gas diffusion layer and catalyst. Experiments were also conducted using methanol vapor as fuel, and it was found to provide performance close to that recorded with pure hydrogen. Experiments were also conducted using several alternative molten salts, including nitrate and chloride eutectics. Combinations of nitrates with hydroxides added to act as a charge carrier produced a working fuel cell, however performance was greatly reduced. Though preliminary, the work described herein demonstrates the great potential of IT-MSFC, and outlines the work needed to make this type of fuel cell practical.