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MELIS, NICOLA. "Synthesis and consecutive reactions of α-aminocyclobutanone derivatives". Doctoral thesis, Università degli Studi di Cagliari, 2017. http://hdl.handle.net/11584/249599.
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The thesis deals with the development and the application of new synthetic methodologies in organic chemistry. The first part describes an organocatalytic enantioselective synthesis of α-(benzylamino) cyclobutanones by employing a tandem condensation/intramolecular rearrangement/proton transfer reaction and starting from α-hydroxycyclobutanone and a selection of benzylamines. In the second part, a practical method for the synthesis of optically active cyclobutanones α-aminoacid esters is presented, via an organocatalytic asymmetric condensation reaction between racemic α-hydroxycyclobutanone and chiral N-alkyl-α-amino ester derivatives. Therefore, an original synthetic protocol for the preparation of highly functionalized tryptamines from α-hydroxycyclobutanone and secondary arylamines via a solvent-free Brønsted acid catalysed two-step reaction sequence is reported in the third part. Finally, the last part covers the synthesis of novel bicyclic oxetanes though Paternò-Büchi reaction and their preliminary evaluation as intermediates for post-functionalization reactions.<br>The thesis deals with the development and the application of new synthetic methodologies in organic chemistry. The first part describes an organocatalytic enantioselective synthesis of α-(benzylamino) cyclobutanones by employing a tandem condensation/intramolecular rearrangement/proton transfer reaction and starting from α-hydroxycyclobutanone and a selection of benzylamines. In the second part, a practical method for the synthesis of optically active cyclobutanones α-aminoacid esters is presented, via an organocatalytic asymmetric condensation reaction between racemic α-hydroxycyclobutanone and chiral N-alkyl-α-amino ester derivatives. Therefore, an original synthetic protocol for the preparation of highly functionalized tryptamines from α-hydroxycyclobutanone and secondary arylamines via a solvent-free Brønsted acid catalysed two-step reaction sequence is reported in the third part. Finally, the last part covers the synthesis of novel bicyclic oxetanes though Paternò-Büchi reaction and their preliminary evaluation as intermediates for post-functionalization reactions.
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Notodarmojo, Suprihanto. "Modelling phosphorus transport in soil and groundwater with two consecutive reactions." Thesis, Notodarmojo, Suprihanto (1992) Modelling phosphorus transport in soil and groundwater with two consecutive reactions. PhD thesis, Murdoch University, 1992. https://researchrepository.murdoch.edu.au/id/eprint/51421/.
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A one-dimensional model of phosphorus transport in soils and groundwater applicable for steady state or transient unsaturated waterflow conditions has been developed. Convective transport, hydrodynamic dispersion and time-dependent phosphorus sorption are accounted for in the model formulation. Time-dependent sorption of phosphorus is considered to follow the empirical model of Barrow and Shaw (1979), which can be described by S = k.Cnt.m The assumed sorption model allows model parameters to be obtained by independent batch and column experiments.
Numerical techniques were used to solve the solute transport equations. For the steady state model, a correction to the numerical dispersion to improve the numerical solution is presented. Analytical solutions for a simplified case are also presented and used to test the numerical solution. For the transient mode 1, numerical solutions of water and solute transport are tested against published data. Parameter sensitivity analysis conducted for the steady state model shows that influent concentration and the parameter k strongly affect the initial breakthrough time for the solute.
The above solute transport equations which assume that the contact time between the entire soil in the column and solute starts when the solute is introduced into the column are also corrected for, by initiating the contact time for every segment in the column when the soil solution is greater than zero. Numerical solutions of the solute transport equations with corrected and non-corrected contact time are also compared. For the range of laboratory soil column experiments, it was found that the difference is small.
Batch experiments and miscible displacement experiments using soil column techniques and sectioned columns were conducted to verify the applicability of the model. For steady state condition, P transport under saturated and unsaturated waterflow conditions were examined. Miscible displacement experiments using soils which had been previously waterlogged for 30 days to see the effect of waterlogging were also conducted. For transient waterflow condition, solute and water transport during infiltration was investigated. Gavin and Joel sandy soils from the Bassendean soil system (Western Australia) and 3 different volcanic soils from Bandung (Indonesia) were used.
Experimental results show that Barrow and Shaw's sorption model can be used to describe phosphorus sorption in batch experiments. The transport model formulated in this study adequately describes the movement of phosphorus in Australian sandy soils, and one of the Indonesian soils. The steady state model, however, fails to simulate the phosphorus movement in other Indonesian soils. In most cases, experimental breakthrough lags behind theoretical curve. The failure of the model is due to the different conditions between continuous miscible displacement experiment in the soil columns and batch shaking experiments. It is recommended that a procedure to carry out batch experiments which minimizes the effect of the presence of antecedent anions and soil-to-solution ratio be developed.
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Rawlinson, James G. T. "Phosphorus-centred radicals in synthesis : development of consecutive radical then ionic reactions and a novel approach towards cannabinoids." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432245.
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Hassan, Sidra [Verfasser], Thomas J. J. [Akademischer Betreuer] Müller, and Jörg [Akademischer Betreuer] Pietruszka. "Lipase Catalyzed Aminolysis as An Entry to Consecutive Multicomponent Reactions. / Sidra Hassan. Gutachter: Jörg Pietruszka. Betreuer: Thomas J. J. Müller." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2014. http://d-nb.info/1058945238/34.
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Nagaki, Aiichiro. "Control of competitive consecutive reaction in organic synthesis." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144941.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第11597号<br>工博第2543号<br>新制||工||1346(附属図書館)<br>23240<br>UT51-2005-D346<br>京都大学大学院工学研究科合成･生物化学専攻<br>(主査)教授 吉田 潤一, 教授 杉野 目道紀, 教授 前 一廣<br>学位規則第4条第1項該当
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SOARES, Arianne de Freitas Barros. "Análise e avaliação entrópica de reações múltiplas consecutivas em reator CSTR." Universidade Federal de Campina Grande, 2017. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/2022.
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Previous issue date: 2017-01-27<br>O presente trabalho estende a metodologia de análise e otimização de processos químicos via minimização da taxa de produção de entropia a um sistema considerado complexo e pouco explorado pela metodologia adotada. Com o intuito de determinar as condições ótimas operacionais do processo, um sistema de reações múltiplas, genéricas e consecutivas conduzidas em um reator de mistura perfeita foi analisado. Tendo em vista que o produto intermediário é o de interesse comercial, o desenvolvimento da metodologia foi baseado nos balanços de massa e energia associados ao balanço entrópico objetivando a minimização da taxa de produção de entropia da reação de interesse. Em conformidade com estudos antecedentes, o procedimento de otimização revelou que a obtenção de uma relação entre a temperatura de alimentação e a temperatura de operação é fundamental para que a condição de mínima produção de entropia seja alcançada. Se tratando da temperatura de reação, uma única condição operacional foi considerada ótima do ponto de vista da mínima produção de entropia, maximizando o rendimento do produto desejado; enquanto que a metodologia clássica de análise e otimização sugeriu diversos pontos operacionais, incluindo um que direciona o sistema para a maximização do produto indesejado em detrimento do produto de interesse. Por se tratar de reações consecutivas, um parâmetro construtivo do reator também foi analisado para alcançar a condição de mínima entropia. A otimização entrópica do tempo de residência revelou que quanto maior for seu valor menor será a taxa de produção de entropia. Uma análise econômica de modo simplificado foi aplicada ao sistema com o intuito de se configurar um critério de seleção de tal parâmetro. Os resultados obtidos revelaram uma nova condição operacional capaz de reduzir os custos energéticos do processo e melhorar o desempenho reacional do sistema.<br>The present study extends the methodology of analysis and optimization of chemical process by minimizing the entropy rate production to a system considered complex and still not explored by the adopted methodology. In order to determinate the optimal operational conditions of the process, a system of multiple generic and consecutive reactions conducted in a perfect mixing reactor was analyzed. Since the intermediate product is of commercial interest, the development of the methodology was based on the mass and energy balances associated with the entropic balance aiming to minimize the entropy rate production of the reaction of interest. In accordance with previous studies, the optimization procedure revealed that obtaining a relation between inlet and operating temperatures is essential to reach the minimum entropy production condition. If treating of reaction temperature, a single operational condition was considered optimal from the point of view of minimum entropy production, while the classical analysis methodology suggested several operating points. Because it is a consecutive reaction, a constructive parameter of the reactor was also analyzed to reach the minimum entropy condition. The entropic optimization of the residence time revealed that the higher its value the lower is the entropy rate production. A simplified economic analysis was applied in order to configure a selection criterion for such parameter. The results reveals a new operating condition capable of reducing the energy costs of the process and improving the reactive performance of the system.
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Maafi, Wassila. "Modelling and elucidation of photoreaction kinetics : applications and actinometry using nifedipine, nisoldipine, montelukast, fluvoxamine and riboflavin." Thesis, De Montfort University, 2016. http://hdl.handle.net/2086/13110.
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The kinetics of drugs photodegradation have traditionally been treated using thermal kinetic analysis methods consisting most commonly in zero and first order kinetics. These treatment strategies were shown to lack specificity and present a number of limitations when applied to photoreactions kinetics. Nevertheless, these methods have widely been used due to a lack of integrated rate-laws for the majority of photoreactions types, in turn, due to the presence of a variable time-dependent factor in most photoreactions rate-laws that prevents their mathematical integration. To address these limitations, a new methodology for the development and validation of semi-empirical integrated rate-laws that faithfully describe photoreactions kinetics and photoreactions simulated cases generated by numerical integration methods (NIMs), is hereby presented. Using this methodology, a new kinetic order was ascribed to photoreactions namely the Φ-order kinetics. Semi-empirical integrated rate-laws were, thus, developed for three photoreaction types namely, unimolecular, AB(1Φ), photoreversible ,AB(2Φ), and consecutive, AB4(4Φ), photoreactions. The proposed models were further tested experimentally on drugs following these photodegradation mechanisms using; nifedipine and nisoldipine for unimolecular photoreactions; montelukast and fluvoxamine for photoreversible reactions; and riboflavin for consecutive photoreactions. The developed models not only accurately described the photoreaction kinetics of these drugs but also allowed the determination of all the kinetic parameters that characterise them. Furthermore, the above studied drugs were shown to act as precise and simple actinometers when analytically treated with the Φ-order kinetic methods, hereby presented. A universal standard method for the precise and worldwide reproducible study of drugs stability and compounds photoreactions, based on monochromatic irradiation and Φ-kinetics data analysis, is also detailed and adopted throughout the thesis. Finally, two new kinetic parameters namely, the pseudo-rate-constant and pseudo-initial velocity have been identified and shown to be more reliable and accurate in the description and universal comparison of photoreactions kinetics.
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Groslambert, Alain. "Etude des perturbations du temps de reaction, de la posture et des adaptations cardio-ventilatoires consecutives a un exercice prolonge : application en tir en biathlon." Besançon, 1997. http://www.theses.fr/1997BESA3904.
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MONTECOT, CELINE. "Role du monoxyde d'azote (no) dans la reaction cerebrovasculaire et dans les dommages neuronaux consecutifs a la crise d'epilepsie." Paris 6, 1998. http://www.theses.fr/1998PA066245.
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Au cours de ce travail, nous avons tente de determiner le role du monoxyde d'azote (no) dans la reaction cerebrovasculaire et les dommages neuronaux consecutifs a la crise d'epilepsie induite par l'acide kainique et de preciser son origine cellulaire. Au niveau cerebral, le no est synthetise de facon constitutive par la no synthase (nos) dite endotheliale localisee dans l'endothelium des vaisseaux sanguins cerebraux et par la nos dite neuronale localisee dans des neurones centraux, des fibres nerveuses perivasculaires et des astrocytes. Nous avons montre chez le rat eveille que le 7-nitro indazole (7-ni), inhibiteur relativement selectif de la nos neuronale reduit l'activite de la nos cerebrale, l'apport sanguin et l'oxygenation tissulaire au niveau du cortex parietal et de l'hippocampe et qu'il protege les neurones pyramidaux des regions ca1 et ca3 de l'hippocampe consecutifs a l'epilepsie. Nous avons egalement mis en evidence que le no synthetise par la nos neuronale joue un role deletere lors d'une ischemie globale transitoire. L'analyse de nos resultats, a la lumiere des donnees bibliographiques, nous a amene a proposer l'hypothese suivante. Le no produit par la nos neuronale est deletere non seulement en participant a la toxicite du glutamate, mais egalement en induisant une perfusion sanguine et une oxygenation tissulaire excessives, conduisant a la formation de l'oxydant cytotoxique, le peroxynitrite ( -oono). Le monoxyde de carbone (co) etant une molecule vasodilatatrice aux proprietes semblables a celles du no, nous avons egalement etudie son role dans la reponse cerebrovasculaire a l'hypercapnie et a l'epilepsie. Nous avons montre que l'inhibition de l'heme oxygenase 2, enzyme constitutive qui synthetise le co, ne modifie ni le debit sanguin cerebral basal, ni la reponse cerebrovasculaire a l'hypercapnie mais, reduit significativement l'augmentation du debit sanguin du neocortex lors de la crise d'epilepsie. Nos resultats suggerent que le co participe a la regulation du debit sanguin cerebral dans des conditions specifiques, notamment celles associees a une liberation accrue de glutamate. Cette etude suggere que le no n'est pas le seul gaz diatomique endogene jouant un role dans l'hyperemie concomitante a l'epilepsie mais que le co serait egalement un mediateur de cette reaction cerebrovasculaire.
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MARTINOVIC, MASSELON SUZANA MULLER JEAN FRANCOIS KLASINC LEO. "IONISATION INDUITE PAR PLASMA LASER DE MOLECULES ORGANIQUES VOLATILES. ETUDE DES PROCESSUS ET DES REACTIONS IONS/MOLECULES CONSECUTIVES PAR SPECTROMETRIE DE MASSE DE RESONANCE CYCLOTRONIQUE A TRANSFORMEE DE FOURIER /." [S.l.] : [s.n.], 1997. ftp://ftp.scd.univ-metz.fr/pub/Theses/1997/Martinovic.Suzana.SMZ9743.pdf.
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Steger, Lukacs Timea. "Etude de la distillation réactive dans une colonne avec un bac intermédiaire avec des réactions consécutives." Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT046G/document.
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La distillation réactive est l’un des procédés chimiques intensifiés les plus reconnus, qui intègre la séparation et la réaction au sein d’un même appareil. Les principaux avantages de la distillation réactive concerne l’amélioration de la conversion de la réaction, la diminution significative des investissements, des coûts de fonctionnement, de la consommation énergétique, et de la production de sous produits. Une méthodologie de conception systématique, générale et hiérarchisée de la distillation réactive discontinue avec des réactions consécutives est présentée dans ce manuscrit. La méthode élaborée est présentée sur la transestérification du carbonate de diméthyle par le procédé de distillation réactive discontinue dans une colonne avec un bac intermédiaire. Après l’acquisition de données phisicochimiques de base nécessaire à notre méthode, une nouvelle méthode de l’analyse de faisabilité pour les systèmes multiréactifs et multiconstituant a été développée. L’étape suivante est l’analyse de sensibilité afin d’explorer les effets des paramètres du procédé. Une configuration faisable, qui est entièrement réactive avec une alimentation dans la partie supérieure et inférieure de la colonne et avec un bac intermédiaire a été choisie et étudiée au cours de l’analyse de sensibilité par des simulations rigoureuses effectuées en utilisant le logiciel ProSIM Batch<br>Reactive distillation, a process integrating separation and reaction in a single unit, is one of the best known intensified chemical processes. Major advantages of reactive distillation include higher conversion, reduced investment, operating costs, energy consumption, and quantity of secondary products. A systematic and hierarchic general methodology for conceptual design of multireactive batch reactive distillation (BRD) is presented in this manuscript. The elaborated method is presented on the transesterification of dimethyl carbonate by the process of batch reactive distillation in a middle vessel column.After collecting the physico-chemical basic data necessary for our method, the new method of feasibility analysis for multicomponent and multireactive systems has been developed. The next step is the sensibility analysis, when the effects of the process parameters are analysed. As a configuration feasible a fully reactive configuration of middle vessel column with entrainer feeding to the upper and lower column sections is studied by simulations using ProSIM Batch
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Lo, Yu-husan, and 羅鈺琁. "Consumer Reactions to Encountering Two Consecutive Service Failures." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/32146218609390428374.
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博士<br>國立臺灣科技大學<br>企業管理系<br>100<br>According to previous studies, many consumers in Taiwan have experienced consecutive service failures. Despite of these failures, many consumers still remain loyal to a service provider for a variety of reasons, such as money deposits, contractual agreements, associated costs, time constrains, and health concerns. We attempt to investigate the emotional reactions and expectations of consumers after they have experienced two consecutive service failures. Our findings reveal that for high involvement services, although customers display strong negative emotional reactions after each service failure, the reaction to the second service failure is less intensive than to the first one. Furthermore, our findings show that as long as the products or services remain in use, customers tend to retain high levels of expectation in regard to the service provider. Consumers to encountering the second service failure are impacted by positive/good and negative/bad news significantly. Consumer dissatisfactions continue to increase, negative emotional responses still intense, and the expections continue to downward. In short, the service provider should take care seriously of widespread consecutive service failures, in order to identifing main topic of the core service and finding out consumers need, and then prescribe the right strategies with actions to retaining loyalty customers and sustainable growth forever.
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Williams, Dennis Bradley Glen. "Consecutive palladium-mediated reactions in the synthesis of some bicyclic systems." Thesis, 2014. http://hdl.handle.net/10210/9145.
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M.Sc. (Chemistry)<br>Palladium-mediated carbon-earbon (and carbon-heteroatom) bond formation! is to an increasing extent playing a vital role in synthetic organic chemistry. The chemistry is usually performed under mild conditions, with the organopal1adium intermediates being formed in situ from inorganic palladium salts or complexes, and has good tolerance of functionality on the substrates. The palladium mediator may be present in the reaction in amounts ranging from stoichiometric to catalytic. Reactions requiring stoichiometric amounts of palladium may appear to be inherently uneconomical. Palladium, however, may be easily recovered in most cases, and may be converted into salts useful for catalysis, effectively offsetting the initial expense. 2 The use of polymer-bound palladium catalysts! has also been shown to be a viable method of palladium recovery. Palladium may form a- or 1r-eomplexes with organic compounds and, as with many other transition-metal complexes, a-palladium complexes are generally only stable in the presence of select ligands. Arylphosphines are most commonly used, and of these triphenylphosphine is the ligand of choice for its availability and low cost...
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Liao, Hsuan-Jen, and 廖宣任. "Structural insight into the mechanism of AsqJ-catalyzed consecutive oxidation reactions." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/kkagv6.
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博士<br>國立臺灣大學<br>生物化學暨分子生物學研究所<br>107<br>AsqJ is a non-heme FeII/2-oxoglutarate-dependent dioxygenase recently discovered in Aspergillus nidulans, which catalyzes the sequential desaturation and epoxidation on the substrate cyclopeptin to produce cyclopenin. Each AsqJ-mediated oxidation step is accompanied by the breakdown of 2-oxoglutarate (2OG) into succinate and CO2, which results in the formation of a high-valent FeⅣ-oxo species as a key intermediate. Crystal structures of the AsqJ in its NiII-substituted state and in complexes with cyclopeptin and its analogs have already been determined. However, a more complete and detailed mechanistic picture of the AsqJ-catalyzed reactions has remained to be further explored. Here, we report the high-resolution crystal structures of iron-bound AsqJ with cyclopeptin and its C3-epimer (D-cyclopeptin), respectively. An XANES spectrum collected from an AsqJ•Fe•2OG•cyclopeptin crystal unambiguously shows the presence of iron in the crystal. This structure provides the first visualization of AsqJ in its native, Fe-bound form. More importantly, different from the binding configuration of cyclopeptin where the C3-H and one of the C10-Hs are poised toward the iron center, in the structure of AsqJ•Fe•2OG•D-cyclopeptin, the C3-H points away from the iron center. These findings suggest that a pathway involving hydrogen atom abstraction at the C10 position of the substrate by a short-lived Fe(IV)-oxo species and the subsequent formation of a carbocation or a hydroxylated intermediate more likely accounts for AsqJ-catalyzed desaturation. We have also determined several structures on AsqJ that may correspond to intermediate states occurred during the epoxidation step, two different binding conformations of 2-CF3 (an analog of cyclopeptin) in complex with AsqJ, and structures resulted from in-crystal reaction. The two intermediate structures of AsqJ and a product-bound AsqJ complex suggest that the AsqJ-catalyzed epoxidation may go through ferric-oxo formation followed by O-C10 bond formation and epoxide production. Interestingly, superimposition analysis shows that the distance from the oxo group to C10 of substrate in conformation 1 of bound 2-CF3 analog (2.6 Å) is longer than the 2.0 Å seen in the intermediate showing O-C10 bond formation. This result may explain why 2-CF3 is less reactive toward AsqJ-catalyzed epoxidation. Finally, crystal structures of two O2 –bound AsqJ complexes with cyclopeptin and dehydrocyclopeptin, the bicyclic Fe(Ⅳ)-peroxyhemiketal intermediate, the Fe(Ⅳ)-oxo intermediate mimicked by VOSO4 replacement, and the Fe(Ⅳ)-oxo intermediate via rearrangement mimicked by soaking succinate are determined. Together, these results not only depict the mechanism of AsqJ-catalyzed desaturation and epoxidation, but also provide more detailed information on dioxygen activation of 2OG-dependent dioxygenase superfamily.
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Sharp, Phillip Patrick. "Consecutive gold[I]-catalysed cyclisation reactions leading to polyfused heterocycles of agrochemical relevance." Phd thesis, 2011. http://hdl.handle.net/1885/151313.
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Variolin B, a marine natural product isolated from the Antarctic sponge Kirkpatrickia variolosa, possesses a rare heterocyclic framework and is a potent CDK inhibitor. Such properties have prompted the industry partner associated with this project, namely the German chemical commodities company BASF, to select this compound as a lead for the development of new agrochemicals. This thesis details the development of new synthetic methods specifically designed to produce complex heterocyclic frameworks related to variolin B. The synthetic plan, which involved consecutive electrophile-promoted nucleophilic ring-closure reactions of 1-[2-(buta-1,3-diynyl)pyridyl]ureas potentially leading to pyrido[3',2':4,5]pyrrolo[1,2-c]pyrimidin-9(8H)-ones, is outlined in Chapter One. The first part of Chapter Two describes the synthesis of alkynylphenylureas as model cascade cyclisation precursors and the second part details the outcomes of reactions of these model compounds with various sources of iodine. The reactions delivered mono-cyclised compounds in some cases although intermolecular side-reactions prevented cascading cyclisation reactions from occurring. Details of the successful development of consecutive gold-catalysed nucleophilic ring-closure reaction of 2-(buta-1,3-diynyl)phenylureas that deliver pyrimido[1,6-a]indol-1(2H)-ones are provided in Chapter Three. The effect that substituents have on the outcome of these gold-promoted reactions were also assessed and it was found that N,N'-disubstituted cyclisation precursors give 1-methylene-1H-imidazo[1,5-a]indol-3(2H)-ones as the major products. Chapter Four outlines the preparation of pyridine-based cyclisation precursors and attempts to synthesise variolin B by applying the gold-catalysed cyclisation methodology to them. These reactions led to mono-cyclised products in some cases but side reactions were also observed. Many of the heterocycles produced during the course of this work are unprecedented and, accordingly, they are being tested for their agrochemical properties by BASF Crop-Protection Division. This aspect of the work is discussed in Appendix 1.
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Shah, Syed Imran A. "The Effects of Mixing, Reaction Rate and Stoichiometry on Yield for Mixing Sensitive Reactions." Master's thesis, 2010. http://hdl.handle.net/10048/1044.
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Competitive-Consecutive and Competitive-Parallel reactions are both mixing sensitive reactions; the yield of desired product from these reactions depends on how fast the reactants are brought together. Recent experimental results have suggested that the mixing effect may depend strongly on the stoichiometry of the reactions. To investigate this, a 1-D, non-dimensional, reaction-diffusion model at the micro-mixing scale has been developed. Assuming constant mass concentration and diffusivities, systems of PDEs have been derived on a mass fraction basis for both types of reactions. A single general Damkhler number and specific dimensionless reaction rate ratios were derived for both reaction schemes. The resulting dimensionless equations were simulated to investigate the effects of mixing, reaction rate ratio and stoichiometry of the reactions. It was found that decreasing the striation thickness and the dimensionless rate ratio maximizes yield for both types of reactions and that the stoichiometry has a considerable effect on yield. All three variables were found to interact strongly. Phase plots showing the interactions between the three variables were developed.
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Brigg, John Robert. "An investigation of a reactor system for two second order consecutive homogeneous liquid reactions." Thesis, 2015. http://hdl.handle.net/10539/16445.
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Kapilakarn, Kulchanat. "Effect of desired product split ratio on the design and control of processes with reversible consecutive reactions /." Diss., 2002. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3073978.
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Hu, Chen-Hsing, and 胡振興. "Effect of the Patch Distribution of A Sphere Surface on A Diffusion-Limited Consecutive Reaction Process." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/v536vs.
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碩士<br>中原大學<br>化學工程研究所<br>98<br>The research is based on a continuous diffusion and incorporation reaction process, involving diffusion of small entities onto the surface of a much larger inclusion and incorporation into two kinds of patches on the inclusion. This system is a diffusion-limited system, whose surface reaction rate is infinite. The normalized overall rate constant of reaction is computed based on the assumption that the dimensionless parameter P(P＝D/kR ) is zero.
The inclusion is assumed a sphere surface, which is with two kinds different of patches (the same of size). The simulation is based on "the first-passage time theory "and "sped-up Brownian dynamic simulation" to explore a diffusion-limited system. The purpose is to investigate the changes of overall rate constant by changing the patch size and the distribution of two patch groups. The rate constant is calculated by varying the separation state of the distributed patch group, i.e. the dimensionless separation index of group (Isg), and the patch coverage fraction (f ) on the sphere surface. The simulation totally releases one million test particles, with releasing one at one time.
In result, we discovered the smaller the patch size, the larger the overall reaction rate constant will be obtained, when patch coverage fraction (f ) is the same. When the separation index of group (Isg) decreases, the overall rate constant will become higher. Increasing the sphere surface coverage also increases the overall rate constant. As well, when the distributed range spread angle increases, the overall rate constant increases. The reaction rate constant is correlated in a positive tread with all different parameters.
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Chin, Thou Long, and 覃昭龍. "The improvement of fourier transform time-resolution in step-scan mode and the application of two-dimension infrared experiment.generalized 2D correlation analysis of parallel^^and consecutive reaction in dynamic system." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/75348421437566207541.
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