Fischer-Tropsch synthesis is the technology for converting fuel feedstocks such as natural gas and coal into transportation fuels and heavy hydrocarbons. There is scope for research and development into integrated processes utilising synthesis gas for the production of a wide range of hydrocarbons. For this purpose there should be strategies for the development of Fischer-Tropsch processes, which consider both economic and technological feasibilities. The aim of this study was to optimize Fischer Tropsch Plants in order to produce gasoline and gas oil by investigating the benefits of recycling & co-feeding of unconverted gas, undesired compounds, and lighter hydrocarbons over iron-based catalysts in order to save on capital and operating costs. This involved development of FT models for both two-phase and three-phase reactors. The kinetic parameters for these models were estimated using optimization with MATLAB fitting to experimental data and these models were then applied to ASPEN HYSYS flowsheets in order to simulate nine different Fischer-Tropsch plant designs. The methodology employed involved qualitative modelling using Driving Force Analysis (DFA) which indicates the necessity of each compound for the Fischer-Tropsch reactions and mechanism. This also predicts each compounds influence on the selectivity of different products for both two-phase and three-phase reactors and for both pure feeding and co-feeding arrangements. In addition, the kinetic models for both two-phase and three-phase reactor were modified to account for parameters such as the size of catalyst particles, reactor diameter and the type of active sites used on the catalyst in order to understand and quantify their effects. The kinetic models developed can describe the hydrocarbon distributions consistently and accurately over large ranges of reaction conditions (480-710K, 0.5-2.5MPa, and H2/CO ratio: 0.5-2.5) over an iron-based catalyst for once-through processes. The effect of recycling and co-feeding on the iron-based catalyst was also investigated in the two reactor types. It was found that co-feeding unwanted compounds to synthesis gas increases the production of hydrocarbons. This recycling and co-feeding led to an increase in H2/CO feed ratio and increased selectivity towards C5+ products in addition to a slightly increased production of light hydrocarbons (C1-C4). Finally, the qualitative model is compared with the quantitative models for both two-phase and three-phase reactors and using both pure feeding and co-feeding with the same reactor conditions. According to the detailed quantitative models developed, in order to maximize hydrocarbon production pressures of 2MPa, temperatures of 450K and a H2/CO feed ratio of 2:1 are required. The ten different Fischer-Tropsch plant cases were based on Fischer-Tropsch process. FT reactor models were built in ASPEN HYSYS and validated with real FT plant data. The results of the simulation and optimization supported the proposed process plant changes suggested by qualitative analysis of the different components influence. The plants involving recycling and co-feeding were found to produce higher quantities of gasoline and gas oil. The proposed heuristic regarding the economic scale of the optimized model was also evaluated and the capital cost of the optimized FT plant reduced comparison with the real FT plant proposed by Gerard. Therefore, the recycling and co-feeding to FT reactor plant was the best efficiency to produce both gasoline and gas oil.

Natural IgM producing phagocytic B cells (NIMPABs) are a rare population of immune cells that can produce antibodies to broadly target and eliminate cancer cells via phosphatidylcholine (PtC)-specific phagocytosis. A novel, dual-labeled lipid-shelled superparamagnetic iron oxide nanoparticle (SPION)-based (SLNP) system was developed to trigger specific phagocytotic behavior in and subsequent enrichment of NIMPABs for a potential immunotherapy. Here we propose the design of an in vitro model to assess cell-SLNP interactions with J774A.1 monocyte cell line and the optimization of SLNP formulation. First, we developed and examined the morphology, size, concentration, purification, sterilization, and storage conditions of oleylamine-coated SPIONs and SLNPs using various microscopy methods, spectroscopy, dynamic light scattering, and zeta potential. Our data confirmed SPIONs are magnetic and 7-8 nm in diameter. SLNPs containing SPIONs retained the magnetic property, and are typically measured between 100-120 nm in diameter, and had a positive zeta potential. Fluorescence labeling of the SLNPs did not affect their properties. Second, we examined cytotoxicity and phagocytosis of SLNPs with J774A.1 cells. Our preliminary data showed that significant percentage of phagocytosis can be observed as early as 2 hours. However, longer than 2 hour incubation resulted in significant cytotoxic effects. The source of SLNP cytotoxicity was examined with transmission electron microscopy and characterization techniques, identifying high un-encapsulated free oleylamine-coated SPION content in SLNP samples contributing to a positive zeta potential for these samples. Simplified SLNPs with oleic acid-coated SPIONs were synthesized and resulting examined particles had a negative zeta potential, reduced free SPION content and improved SPION incorporation into SLNP cores. Based on these findings, SLNP criteria, characterization techniques, and cell assays were revised to establish a rigorous, standardized workflow essential for determining the optimal SLNP formulation. Future work must continue to modify SLNP formulation with information obtained from all characterization techniques and cellular assays outlined in the in vitro model. Once optimized, selective SLNP-mediated isolation of NIMPAB cells can be validated ex vivo with murine peritoneal cavity washout cells and then human peripheral blood samples. / 2024-08-26T00:00:00Z

New view synthesis (NVS) is the problem of generating a novel image of a scene, given a set of calibrated input images of the scene, i.e. their viewpoints, and also that of the output image, are known. The problem is generally ill-posed---a large number of scenes can generate a given set of images, therefore there may be many equally likely (given the input data) output views. Some of these views will look less natural to a human observer than others, so prior knowledge of natural scenes is required to ensure that the result is visually plausible. The aim of this thesis is to compare and improve upon the various Markov random field} and conditional random field prior models, and their associated maximum a posteriori optimization frameworks, that are currently the state of the art for NVS and stereo (itself a means to NVS). A hierarchical example-based image prior is introduced which, when combined with a multi-resolution framework, accelerates inference by an order of magnitude, whilst also improving the quality of rendering. A parametric image prior is tested using a number of novel discrete optimization algorithms. This general prior is found to be less well suited to the NVS problem than sequence-specific priors, generating two forms of undesirable artifact, which are discussed. A novel pairwise clique image prior is developed, allowing inference using powerful optimizers. The prior is shown to perform better than a range of other pairwise image priors, distinguishing as it does between natural and artificial texture discontinuities. A dense stereo algorithm with geometrical occlusion model is converted to the task of NVS. In doing so, a number of challenges are novelly addressed; in particular, the new pairwise image prior is employed to align depth discontinuities with genuine texture edges in the output image. The resulting joint prior over smoothness and texture is shown to produce cutting edge rendering performance. Finally, a powerful new inference framework for stereo that allows the tractable optimization of second order smoothness priors is introduced. The second order priors are shown to improve reconstruction over first order priors in a number of situations.

<p dir="ltr">Reported herein is a brief summary regarding the previous syntheses of borane-amines, newly developed protocols to synthesize borane-amines, and the material and synthetic applications utilizing borane-amines. Methods to generate borane-amines typically relied on a metathesis-dehydrogenation reaction between ammonium salts and metal borohydrides in organic solvent, typically hazardous tetrahydrofuran (THF). However, due to the poor solubility of inorganic salts in organic solvent, stirring of the reaction mixture becomes difficult and, in turn, scalability is made challenging. We report two new methods to generate borane-amines that both rely on the hydroboration of sodium borohydride and a carbonyl activator, followed by the S_N2-type reaction with the amine to form the requisite borane-amine. The activator for our procedures are either 1) gaseous carbon dioxide or 2) water/ethyl acetate system. The CO₂ mediated protocol was applied to a variety of 1°-, 2°-, 3°-, and heteroaromatic amines as well as phosphines to form the corresponding borane adducts (73-99%). Water was also found to be a green, compatible activator. Interestingly, we had swapped environmentally and health hazardous THF with ethyl acetate (EtOAc) and found the reaction had still proceeded with competitive conversion of amines to the borane-amines (72-97%). The robustness of this reaction was demonstrated with a 1.1 mol scale synthesis of borane pyridine with 87% yield. With increased accessibility of borane-amines established, we sought to investigate their potential applications, including testing their hypergolic properties. Additionally, we utilized borane-ammonia for a sequential reduction/Friedel-Crafts alkylation of benzyl carbonyls. Traditionally an alkyl halide, the scope of the electrophilic aromatic substitution reaction has widened to include alcohols and carbonyls as potential Friedel-Crafts reactants. Few reports exist for the arylation of aldehydes and ketones, while no precedence exists for the arylation of carboxylic acids and esters. Our group previously reported that TiCl₄ is capable of eliminating oxygen from benzyl alcohols, forming a carbocation intermediate. Theoretically, the carbocation formed from TiCl₄ and benzyl alcohols would be vulnerable from attacks from other nucleophiles, including pi bonds from arenes. This was indeed proven to be the case when benzyl alcohol was reacted in 1 equiv. TiCl₄with benzene as the solvent and diphenylmethane was obtained as the sole product. By including borane-ammonia as a hydride source, various aryl carbonyls and aryl carbinols were also reduced to the corresponding alcohol <i>in situ</i>, enabling these substrates to participate in Friedel-Crafts alkylation.</p>

Orientador: Alexandre César Rodrigues da Silva / Resumo: Neste trabalho foram programados dois algoritmos descritos na literatura denominados de XOR e MDM que realizam a síntese de circuitos reversíveis a partir da tabela verdade. Programou-se também algoritmos relacionados com a otimização pós-síntese, denominados Greedy, Simulated Annealing e Variable Neighbourhood Descent, que empregam métodos heurísticos e regras de reescrita, cujo objetivo é reduzir a quantidade de portas lógicas reversíveis do circuito sintetizado. A contribuição deste trabalho foi o emprego do método Divisão que divide o circuito sintetizado em vizinhanças e aplica o método Simulated Annealing ou Variable Neighbourhood Descent nas partes do circuito. Os métodos de otimização implementados foram comparados utilizando como testes 42 circuitos. Constatou-se que os métodos Simulated Annealing e Variable Neighbourhood Descent em conjunto com o método Divisão geraram circuitos menores. Além disso, o algoritmo que aplica a meta-heurística Simulated Annealing comparado ao Variable Neighbourhood Descent obteve menor quantidade de portas em 7 dos 42 circuitos, mesmo custo em 29 circuitos e pior custo em 6. / Abstract: In this work, two algorithms described in the literature denominated of XOR and MDM are programmes that realize the synthesis of reversible circuits from the truth table. It has been programmed also algorithms related to the post-synthesis optimization, called Greedy, Simulated Annealing and Variable Neighbourhood Descent, which use heuristic methods and rewriting rules, whose objective is to reduce the number of reversible logic gates of the synthesized circuit. The contribution of this work was the use of the Division method that divides the synthesized circuit into neighborhoods and applies the Simulated Annealing or Variable Neighbourhood Descent method in the circuit parts. The implemented optimization methods were compared using 42 circuits as a test. It was found that the Simulated Annealing and Variable Neighborhood Descent methods together with the Division method generated smaller circuits. Furthermore, the algorithm that applies the Simulated Annealing meta-heuristic compared to the Variable Neighbourhood Descent obtained the lowest number of gates in 7 of the 42 circuits, even cost in 29 circuits and the worst cost in 6. / Mestre

Esta tese tem como objetivo estudar a derivatização da celulose sob condições homogêneas, utilizando líquidos iônicos (LIs), em micro-ondas, através de um método simples e reprodutível. Foram estudadas três etapas: i) Síntese dos LIs, buscando otimizar seu preparo; ii) Efeitos da estrutura dos LIs sobre a dissolução de celulose; iii) Otimização da derivatização da celulose em LIs. Foi realizado um planejamento experimental para a otimização da síntese dos LIs, mostrando-se que o uso de solvente molecular como diluente não traz vantagens. Na dissolução de celuloses fibrosas em LIs, observou-se a importância das estruturas dos cátions e ânions destes. Estudou-se a influência de um solvente molecular, DMSO, na reação de derivatização de celulose em LIs e percebeu-se que o uso do mesmo não é vantajoso. Por fim, realizou-se um planejamento experimental da acetilação da celulose, mostrando-se quais fatores mais afetam esse processo: tempo de reação, razão molar de anidrido acético/celulose e temperatura / The work reported has the target of studying the acylation of cellulose under homogeneous reaction conditions. Imidazolium-based ionic Liquids (ILs) were employed as solvents, and the reaction was assisted by a microwave. These following processes have been studied: Optimization of the synthesis of ILs; ii) Effects of the structure of ILs on the dissolution of cellulose; iii) Optimization of cellulose acylation. Experimental design has been applied in order to optimize the synthesis of ILs. The use of DMSO as a diluent decreased the efficiency of the synthesis. Dissolution of cellulose (eucalyptus, mercerized eucalyptus and mercerized cotton) in several ILs has shown the importance of the counter-ion and the structure of the cation side-chain. The addition of DMSO decreased the amount of dissolved cellulose. Experimental design has been applied in order to optimize the acetylation of cellulose. Reaction time, molar ratio acetic anhydride/anhydroglucose unit, and cellulose concentration influenced the reaction outcome.

Esta tese tem como objetivo estudar a derivatização da celulose sob condições homogêneas, utilizando líquidos iônicos (LIs), em micro-ondas, através de um método simples e reprodutível. Foram estudadas três etapas: i) Síntese dos LIs, buscando otimizar seu preparo; ii) Efeitos da estrutura dos LIs sobre a dissolução de celulose; iii) Otimização da derivatização da celulose em LIs. Foi realizado um planejamento experimental para a otimização da síntese dos LIs, mostrando-se que o uso de solvente molecular como diluente não traz vantagens. Na dissolução de celuloses fibrosas em LIs, observou-se a importância das estruturas dos cátions e ânions destes. Estudou-se a influência de um solvente molecular, DMSO, na reação de derivatização de celulose em LIs e percebeu-se que o uso do mesmo não é vantajoso. Por fim, realizou-se um planejamento experimental da acetilação da celulose, mostrando-se quais fatores mais afetam esse processo: tempo de reação, razão molar de anidrido acético/celulose e temperatura / The work reported has the target of studying the acylation of cellulose under homogeneous reaction conditions. Imidazolium-based ionic Liquids (ILs) were employed as solvents, and the reaction was assisted by a microwave. These following processes have been studied: Optimization of the synthesis of ILs; ii) Effects of the structure of ILs on the dissolution of cellulose; iii) Optimization of cellulose acylation. Experimental design has been applied in order to optimize the synthesis of ILs. The use of DMSO as a diluent decreased the efficiency of the synthesis. Dissolution of cellulose (eucalyptus, mercerized eucalyptus and mercerized cotton) in several ILs has shown the importance of the counter-ion and the structure of the cation side-chain. The addition of DMSO decreased the amount of dissolved cellulose. Experimental design has been applied in order to optimize the acetylation of cellulose. Reaction time, molar ratio acetic anhydride/anhydroglucose unit, and cellulose concentration influenced the reaction outcome.