In this study, two new Multi-Objective Optimization (MOO) techniques are developed. The two new techniques, the Objective-Based Gradient Algorithm (OBGA) and the Principal Component Grid Algorithm (PCGA), were developed with the goals of improving the accuracy and efficiency of the Pareto domain approximation relative to current MOO techniques. Both methods were compared to current MOO techniques using several test problems. It was found that both the OBGA and PCGA systematically produced a more accurate Pareto domain than current MOO techniques used for comparison, for all problems studied. The OBGA requires less computation time than the current MOO methods for relatively simple problems whereas for more complex objective functions, the computation time was larger. On the other hand, the efficiency of the PCGA was higher than the current MOO techniques for all problems tested. The new techniques were also applied to complex chemical engineering problems. The OBGA was applied to an industrial reactor producing ethylene oxide from ethylene. The optimization varied four of the reactor input parameters, and the selectivity, productivity and a safety factor related to the presence of oxygen in the reactor were maximized. From the optimization results, recommendations were made based on the ideal reactor operating conditions, and the control of key reactor parameters. The PCGA was applied to a PI controller model to develop new tuning methods based on the Pareto domain. The developed controller tuning methods were compared to several previously developed controller correlations. It was found that all previously developed controller correlations showed equal or worse performance than that based on the Pareto domain. The tuning methods were applied to a fourth order process and a process with a disturbance, and demonstrated excellent performance.

Ethylene oxide (EO) is a very versatile compound with considerable energy in its ring structure. Its reactions proceed mainly via ring opening and are highly exothermic. Under some conditions, it is known to undergo a variety of reactions, such as isomerization, polymerization, hydrolysis, combustion and decomposition Due to its very reactive characteristic and widely industrial applications, EO has been involved in a number of serious incidents such as Doe Run 1962, Freeport 1974, Deer Park 1988 and Union Carbide Corporation’s Seadrift 1991. The impacts can be severe in terms of death and injury to people, damage to physical property and effects on the environment. For instance, the Union Carbide incident in 1991 caused one fatality and extensive damage to the plant with the property damage of up to 80 million dollars. Contamination has a considerable impact on EO reactivity by accelerating substantially its decomposition and playing a key role on EO incidents. In this work, the reactivity of EO with contaminants such as KOH, NaOH, NH4OH, and EDTA is evaluated. Useful information that is critical to the design and operation of safer chemical plant processes was generated such as safe storage temperatures (onset temperature), maximum temperature, maximum pressure, temperature vs. time, heat and pressure generation rates as a function of temperature and time to maximum rate using adiabatic calorimetry. A special arrangement for the filling-up of the cell was constructed due to the gaseous nature and toxicity of EO. A comparison of their thermal behavior is also presented since several contaminants are studied.

In this study, two new Multi-Objective Optimization (MOO) techniques are developed. The two new techniques, the Objective-Based Gradient Algorithm (OBGA) and the Principal Component Grid Algorithm (PCGA), were developed with the goals of improving the accuracy and efficiency of the Pareto domain approximation relative to current MOO techniques. Both methods were compared to current MOO techniques using several test problems. It was found that both the OBGA and PCGA systematically produced a more accurate Pareto domain than current MOO techniques used for comparison, for all problems studied. The OBGA requires less computation time than the current MOO methods for relatively simple problems whereas for more complex objective functions, the computation time was larger. On the other hand, the efficiency of the PCGA was higher than the current MOO techniques for all problems tested. The new techniques were also applied to complex chemical engineering problems. The OBGA was applied to an industrial reactor producing ethylene oxide from ethylene. The optimization varied four of the reactor input parameters, and the selectivity, productivity and a safety factor related to the presence of oxygen in the reactor were maximized. From the optimization results, recommendations were made based on the ideal reactor operating conditions, and the control of key reactor parameters. The PCGA was applied to a PI controller model to develop new tuning methods based on the Pareto domain. The developed controller tuning methods were compared to several previously developed controller correlations. It was found that all previously developed controller correlations showed equal or worse performance than that based on the Pareto domain. The tuning methods were applied to a fourth order process and a process with a disturbance, and demonstrated excellent performance.

Orientador: Maria Isabel Pedreira de Freitas Ceribelli / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-10T03:14:42Z (GMT). No. of bitstreams: 1 Abdo_Nelyan_D.pdf: 1704147 bytes, checksum: 34b769db6d0f1c4ead0ac4c2a3cca581 (MD5) Previous issue date: 2006 / Resumo: A etapa da aeração em um ciclo de esterilização a Óxido de Etileno (OE) corresponde à fase de retirada de resíduos tóxicos dos artigos processados neste método. A aeração pode ocorrer por meio de equipamentos destinados para o processo ou ainda em ambientes projetados para essa finalidade. O presente estudo tem como objetivo descrever como vem se desenvolvendo a prática da aeração dos artigos odonto-médico-hospitalares (AOMH) em empresas terceirizadoras de esterilização a OE, na região sudeste do país, tendo como referência a Portaria Interministerial No. 482, de 16 de Abril de 1999 vigente e orientações internacionais relacionadas ao tema.Trata-se de um estudo descritivo, com dados coletados através de instrumento aplicado presencialmente pela pesquisadora, que versou sobre a caracterização das empresas, dos parâmetros do processo de esterilização, período e características da aeração realizada. Foram entrevistados os responsáveis técnicos de 10 das 12 empresas existentes na referida região. Para tratamento dos dados foram utilizadas tabelas de freqüência para variáveis categóricas e estatísticas descritivas para as variáveis contínuas. Como resultado, observou-se que as empresas foram caracterizadas com número de clientes acima de 300 para 60% dos respondentes, concentramse no interior da região sudeste e todas apresentam profissionais responsáveis graduados na área da saúde. Com referência aos parâmetros do ciclo de esterilização os dados foram bastante heterogêneos. Sobre a aeração, 60% das empresas usam a aeração ambiental e 40% a mecânica. Em todas as questões sobre aeração, os dados foram dispersos indicando uma não homogeneidade de ação. A PI482 (1999) não menciona o tempo de aeração ambiental (AA) indicado para o processo, apesar de orientar sobre a existência de uma sala de aeração e também não menciona qualquer informação sobre aeração mecânica (AM). Neste aspecto, as empresas estão adequadas sendo que 100% delas possuem sala de aeração, mas apresentam parâmetros heterogêneos para utilização da AA. As orientações internacionais analisadas, oferecem dados objetivos sobre os tipos de aeração e sobre quais fatores que podem interferir no processo. Devido à diversidade de fatores que interferem no processo de aeração, uma orientação genérica é indicada pelas principais organizações internacionais e que preconiza o uso de aeração mecânica aquecida por 8h a 60ºC ou 12h a 50ºC. Neste aspecto, nenhuma das empresas pesquisadas mostrou adequação sendo que as que utilizam AM, trabalham com temperaturas e tempos diferentes dos preconizados. Quanto ao fator que determina o tempo de entrega do AOMH para uso, não houve consenso e obteve-se a maioria dos respondentes indicando o tempo de resposta de teste biológico como o fator preponderante. Conclui-se que a aeração de AOMH realizado em empresas terceirizadas de esterilização a OE na região sudeste, encontra-se adequada em relação à PI 482 (1999), no que se refere à estrutura física enquanto as orientações sobre parâmetros da aeração, não são bem estabelecidas nas empresas estudadas. Quanto às orientações internacionais para aeração de AOMH, as empresas não se encontram em conformidade com o preconizado o que conduz à necessidade da avaliação efetiva do processo realizado atualmente / Abstract: The stage of the aeration in a sterilization cycle the Oxide of Etileno (OE) corresponds to the phase of withdrawal of toxic residues of articles processed in this method. The aeration can still occur by means of equipment destined for the process or in projected environments for this purpose. The present study it has as objective to describe as it comes if developing practical of the aeration of dentalmedical- hospital devices (AOMH) in outsourced companies of sterilization the OE, in the Southeastern region of the country, having as reference Inter-ministerial PI 482, dated April 16, 1999 of effective related international guidelines. One is about a descriptive study, with data collected through instrument applied actually for the researcher, that turned on the characterization of the companies, of the parameters of the process of sterilization, period and characteristics of the carried through aeration. They had been interviewed responsible the technician of 10 of the 12 existing companies in the related region. For treatment of the data tables of frequency for categorical variable had been used and statistical descriptive for the continuous variable. As result, it was observed that the companies had been characterized with number of customers above of 300 for 60% of the respondents, are concentrated in the interior of the Southeastern region and all present responsible professionals graduated the area of the health. Regarding to the parameters of the sterilization cycle the data had been sufficiently heterogeneous. On the aeration, 60% of the companies use ambient aeration and 40% the mechanics. In all the questions on aeration, the data had been dispersed indicating not a homogeneity of action. The PI482 (1999) does not mention the time of ambient aeration (AA) indicated for the process, although to guide on the existence of a aeration room and also it does not mention any information on aeration mechanics (AM). In this aspect, the companies are adjusted being that 100% of them they possess aeration room, but present heterogeneous parameters for use of the AA. The analyzed international guidelines, offer given objective on the types of aeration and which factors that can intervene with the process. Due to diversity of factors that intervene with the aeration process, a generic orientation is indicated by the main international organizations and that it praises the aeration use warm mechanics for 8h 60ºC or 12h 50ºC. In this aspect, none of the searched companies showed adequacy being that the ones that use AM, work with temperatures and different times of the praised ones. How much to the factor that it determines the time of delivery of the DMHD for use, did not have consensus and got it majority of the respondents indicating the time of reply of biological test as the preponderant factor. The aeration of DMHD is concluded that carried through in outsourced companies of sterilization the OE in the Southeastern region, meets adequate in relation to PI 482 (1999), as for the physical structure while the guidelines on parameters of the aeration, well are not established in the studied companies. How much to the international guidelines for aeration of DMHD, the companies do not meet in compliance with the praised one what she leads to the necessity of the evaluation accomplishes of the process carried through currently / Doutorado / Enfermagem e Trabalho / Mestre em Enfermagem

Orientadores: Maria Alvina Krähenbühl, José Roberto Nunhez / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-16T15:11:20Z (GMT). No. of bitstreams: 1 Mello_FaustoHenriquede_M.pdf: 1167990 bytes, checksum: e645a2438e712db3fe9b9ea7d7a66077 (MD5) Previous issue date: 2010 / Resumo: Neste trabalho foi simulado o processo de Absorção, Stripping e Reabsorção de Óxido de Etileno, avaliando-se a influência da não idealidade da fase líquida, os melhores modelos para representar essa não idealidade, diferentes formas de cálculo de eficiência de coluna e os perfis de temperatura e concentração gerados pelo simulador comercial Aspen Plus®. Foi mostrado também, como a representação pontual de um processo de separação pelo ajuste da eficiência de separação, pode levar à falsa idéia de se ter obtido a representação de um sistema de separação. Foram realizadas análises de sensibilidade que, além de permitir um maior entendimento do comportamento operacional dos equipamentos, também permitiu avaliar a adequação do modelo termodinâmico e dos parâmetros binários utilizados na simulação desse sistema de separação. No caso estudado, é muito importante a representação do equilíbrio líquido vapor entre o óxido de etileno (OE) e a água, em função da forte não idealidade da fase líquida. Para a mistura OE + água, apesar de comum na indústria, é difícil de se encontrar na literatura dados de equilíbrio em condições próximas às de operação da unidade industrial, em função da alta reatividade entre o OE e a água, e por o OE ser um produto muito tóxico e de alta periculosidade. Os resultados da simulação apresentaram-se em sua maioria, bastante satisfatórios em relação aos dados de processo / Abstract: In this work the process of Absorption, Stripping and Reabsorption of Ethylene Oxide was simulated, evaluating the influence of non-ideality of the liquid phase, the best models to represent this non-ideality, different ways to calculate the efficiency of the column and temperature and concentration profiles generated by the commercial simulator Aspen Plus®. It was also shown, how the punctual representation of a separation process by adjusting the separation efficiency, can lead to the false idea of having obtained the representation of a separation system. Sensitivity analysis were performed which, besides allowing a better understanding of the operational performance of the equipment, also allowed to evaluate the adequacy of thermodynamic model and the binary parameters used in the simulation of this separation system. In the case studied, the representation of the vapor liquid equilibrium between the Ethylene Oxide (EO) and water is very important, due to the strong non-ideality of the liquid phase. For EO + water mixture, although common in the industry, it is hard to find in the literature equilibrium data for conditions similar to the operation of the plant, due to the high reactivity between EO and water, and EO be a product very toxic and highly hazardous. The simulation results presented are mostly quite satisfactory in relation to process data / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química

In this study, two new Multi-Objective Optimization (MOO) techniques are developed. The two new techniques, the Objective-Based Gradient Algorithm (OBGA) and the Principal Component Grid Algorithm (PCGA), were developed with the goals of improving the accuracy and efficiency of the Pareto domain approximation relative to current MOO techniques. Both methods were compared to current MOO techniques using several test problems. It was found that both the OBGA and PCGA systematically produced a more accurate Pareto domain than current MOO techniques used for comparison, for all problems studied. The OBGA requires less computation time than the current MOO methods for relatively simple problems whereas for more complex objective functions, the computation time was larger. On the other hand, the efficiency of the PCGA was higher than the current MOO techniques for all problems tested. The new techniques were also applied to complex chemical engineering problems. The OBGA was applied to an industrial reactor producing ethylene oxide from ethylene. The optimization varied four of the reactor input parameters, and the selectivity, productivity and a safety factor related to the presence of oxygen in the reactor were maximized. From the optimization results, recommendations were made based on the ideal reactor operating conditions, and the control of key reactor parameters. The PCGA was applied to a PI controller model to develop new tuning methods based on the Pareto domain. The developed controller tuning methods were compared to several previously developed controller correlations. It was found that all previously developed controller correlations showed equal or worse performance than that based on the Pareto domain. The tuning methods were applied to a fourth order process and a process with a disturbance, and demonstrated excellent performance.

Amphiphilic tri- and penta-block copolymers containing a polyurethane central block with pendant carboxylic acid groups flanked by hydroxyl functional polyether tails were synthesized. Our intention was to investigate the activities of these copolymers as dispersants for magnetite nanoparticles in biological media. A benzyl alkoxide initiator was utilized to prepare poly(ethylene oxide) (BzO-PEO-OH), poly(propylene oxide) (BzO-PPO-OH) and poly(ethylene oxide-b-propylene oxide) (poly(BzO-EO-b-PO-OH)) oligomeric tail blocks with varying lengths of PEO and PPO. The oligomers had a hydroxyl group at the terminal chain end and a benzyl-protected hydroxyl group at the initiated end. The polyether oligomers were incorporated into a block copolymer with a short polyurethane segment having approximately three carboxylic acid groups per chain. The block co-polyurethane was then hydrogenated to remove the benzyl group and yield primary hydroxyl functionality at the chain ends. End group analysis by 1H NMR showed the targeted ratio of PEO to PPO demonstrating control over block copolymer composition. Number average molecular weights determined by both 1H NMR and GPC were in agreement and close to targeted values demonstrating control over molecular weight. Titrations of the pentablock copolymers showed that the targeted value of approximately three carboxylic acid groups per chain was achieved. Heterobifunctional poly(ethylene oxide) (PEO) and poly(ethylene oxide-b-propylene oxide) (PEO-b-PPO) copolymers were synthesized utilizing heterobifunctional initiators to yield polymers having a hydroxyl group at one chain end and additional moieties at the other chain end. For PEO homopolymers, these moieties include maleimide, vinylsilane, and carboxylic acid functional groups. Heterobifunctional PEO oligomers with a maliemide end group were synthesized utilizing a double metal cyanide coordination catalyst to avoid side reactions that occur with a basic catalyst. PEO oligomers with vinylsilane end groups were synthesized via alkoxide-initiated living ring-opening polymerization, and this produced polymers with narrow molecular weight distributions. Heterobifunctional PEO-b-PPO block copolymers were synthesized in two steps where the double metal cyanide catalyst was used to polymerize propylene oxide (PO) initiated by 3-hydroxypropyltrivinylsilane. The PPO was then utilized as a macroinitiator to polymerize ethylene oxide (EO) with base catalysis. Heterobifunctional PEO and PEO-b-PPO block copolymers possessing carboxylic acid functional groups on one end were synthesized by reacting the vinyl groups with mercaptoacetic acid via an ene-thiol addition. / Ph. D.

Superparamagnetic Magnetite (Fe3O4) nanoparticles were synthesized and complexed with carboxylate-functionalized block copolymers, and aqueous dispersions of the complexes were investigated as functions of their chemical and morphological structures. The block copolymer dispersants possessed either poly(ethylene oxide), poly(ethylene oxide-co-propylene oxide), or poly(ethylene oxide-b-propylene oxide) outer blocks, and all contained a polyurethane center block with pendant carboxylate functional groups. The complexes were formed through interactions of the carboxylates with the surfaces of the magnetite nanoparticles. Initial efforts utilized an aqueous coprecipitation method for the synthesis of magnetite nanoparticles, which yielded polydisperse magnetite nanoparticles. The nanoparticle complexes were characterized with a range of solution- and solid-state techniques including TGA, XPS, TEM, VSM, DLS and zeta potential measurements. DLVO calculation methods, which sum the contributions from van der Waals, steric, electrostatic and magnetic forces were utilized to examine the interparticle potentials in the presence and absence of external magnetic fields. Compositions were identified wherein a shallow, attractive interparticle potential minimum appears once the magnetic term is applied. This suggested the possibility of tuning the structures of superparamagnetic nanoparticle shells to allow discrete dispersions without a field, yet permit weak flocculation upon exposure to a field. This property has important implications for biomedical applications where movement of particles with an external magnetic field is desirable. In a second study, well-defined, narrow size dispersity magnetite nanoparticles were synthesized via the thermolysis of an iron (III) acetylacetonate (Fe(acac)3) precursor in the presence of benzyl alcohol. The magnetite nanoparticles were coated with triblock and pentablock copolymers possessing poly(ethylene oxide) and poly(propylene oxide-b-ethylene oxide) tailblocks and the carboxylate-functional anchor block. DLVO calculations were applied to the new magnetite particles and diagrams of potential energy versus interparticle distance indicated the predominant effect of steric and magnetic interactions on the particle stability. Exposure of the pentablock copolymer-magnetite complexes in phosphate buffered saline to a 1500 Oe magnetic field with concomitant DLS measurements indicated flocculation of the magnetic nanoparticles. DLS measurements showed increased hydrodynamic radii and scattering intensities with time. / Ph. D.

Salmonella enterica has been associated with several outbreaks due to consumption of low water activity foods including spices. Consequently, to improve microbiological quality, spices are commonly treated before ultimately reaching consumers. These processes may result in sub-lethal injury to cells, which can lead to an underestimation of microbial populations when plating on selective media. Sub-lethally injured cells are difficult to enumerate due to reduced ability to grow on selective microbiological media. Poor recovery of sub-lethally-injured cells may obscure process validation results and lead to overestimation of process effect. Therefore, this work was performed to determine the influence of agar overlay and media supplementation methods on the recovery of Salmonella from steam and ethylene oxide treated peppercorns and cumin seeds. Traditional agar overlay allowed recovery of significantly more Salmonella (p < 0.05) from inoculated peppercorns treated with steam (65.5C, 15 sec.) than selective media (XLT4) or solid agar overlay. Additional supplementation of the TSA base to contain 3,3'-thiodipropionic acid further improved Salmonella recovery from steam treated peppercorns (p < 0.05). For peppercorns and cumin seeds subjected to ethylene oxide, neither sodium pyruvate + yeast extract, 3,3'-thiodipropionic acid, glycerophosphate, ATP, nor magnesium enhanced recovery compared to overlay alone but both methods recovered significantly higher numbers than XLT-4 alone (p < 0.05) for both cumin seeds and peppercorns. / Master of Science in Life Sciences

Amphiphilic block copolymers consisting of poly(ethylene oxide) and poly(lactide) have great potential for formulating drug delivery systems. Our approach was to synthesize poly(ethylene oxide-b-D,L-lactide), (PEO-b-PDLLA), block copolymers with controlled molecular weights and good functionality on the poly(ethylene oxide) end for the design of potential core-shell delivery vehicles for HIV drugs. PEO-b-PDLLA block copolymer was used as a polymeric nanocarrier to encapsulate the HIV protease inhibitor, Ritonavir, within magnetite nanoparticles. Well-defined multifunctional polymeric nanoparticles with controlled sizes and size distributions were fabricated by rapid nanoprecipitation using blends of the PEO-b-PDLLA block copolymer with poly(L-lactide), (PLLA) homopolymer. Heterobifunctional PEO oligomers were directly prepared by initiating ethylene oxide with functional alcohols bearing vinylsilane, vinylether and maleimide moieties to provide appropriate end groups for conjugating targeting ligands. The polyethers with narrow molecular weight distributions were utilized as macroinitiators for the synthesis of poly(lactide) block. Heterobifunctional diblock copolymers possessing carboxylic acids were prepared from ene-thiol addition reaction of mercaptoacetic acid across the vinyl group on the PEO end, while preserving the hydroxyl functionality on the other end. Additionally, PDLLAs bearing maleimide functionality with controlled molecular weights were synthesized using maleimide functional initiator. End group modification was performed via  Michael addition using cysteamine hydrochloride to introduce an amino group over the vinyl bond. The resulting carboxylic acid functional PEO-b-PDLLA diblock copolymers, and amino functional PDLLAs are potential biocompatible polymers that can be utilized to encapsulate an array of bioactive molecules, targeting ligands. / Master of Science