In this work, methylmethacrylate, MMA was polymerized by ATRP method to obtain low molecular weight living polymers. The initiator was p-toluenesulfonylchloride and catalyst ligand complex system were CuCl-4,4&rsquo / dimethyl 2,2&rsquo / bipyridine. Polymers with controlled molecular weight were obtained. The polymer chains were shown by NMR investigation to be mostly syndiotactic. The molecular weight and molecular weight distribution of some polymer samples were measured by GPC method. The K and a constants in [h]=K Ma equation were measured as 9.13x10-5 and 0.74, respectively. FT-IR and X-Ray results showed regularity in polymer chains. The molecular weight-Tg relations were verified from results of molecular weight-DSC results.

O presente trabalho propÃe o estudo comparativo de duas tÃcnicas de controle aplicadas Ãs trajetÃrias de um robà mÃvel: GPC (Generalized Predictive Control) e PID (Proporcional â Integral ‐ Derivativo). O sistema de controle do robà utiliza a configuraÃÃo em cascata, sendo constituÃdo de uma malha interna para o controle de velocidade dos motores e uma malha externa para o controle de posiÃÃo e orientaÃÃo do robà que fornecerà a referÃncia de velocidade dos motores. O sistema de controle em cascata permite utilizar‐se de controladores cinemÃticos mono‐variÃvel. Foi utilizado ainda um controlador dinÃmico preditivo multivariÃvel a fim de se comparar o desempenho com os outros controladores mono‐variÃvel. Foram desenvolvidos simuladores para o robà mÃvel atravÃs de uso dos controladores GPC e PID. A teoria foi implementada em um pequeno robà mÃvel com traÃÃo diferencial construÃdo para este propÃsito. Foram utilizados como atuadores motores CC e como sensores de velocidade e posiÃÃo, foram utilizados encoders e sonares, respectivamente. Uma vez que o ajuste dos controladores usados à baseado em modelo, foram utilizados dois mÃtodos de identificaÃÃo de parÃmetros: o MÃtodo dos MÃnimos Quadrados Recursivos (MQR) e por Redes Neurais. Os mÃtodos de controle empregados permitiram o seguimento de trajetÃrias pelo robà mÃvel. / The present work proposes a comparative study of two control techniques applied for mobile robots trajectories: GPC (Generalized Predictive Control) and PID (Proportional â Integral ‐ Derivative). The control system uses a cascade configuration composed by an internal loop for controlling the speed of motors, and an external loop for position and orientation control, being used to get the reference speed motors. This cascade control system can run a monovariable cinematic controller. It was used a multi‐variable predictive controller to compare the behavior with the single‐variable controllers. It was developed simulators for mobile robot using GPC and PID controllers. The theory was applied to a little differential mobile robot, designed to this proposes. It was used as actuators DC motors, and speed e positional sensors, encoders and sonar, respectively. Once the controllers adjust are referenced by model, was used two identification methods: Recursive Minimum Square and Neural Networks. The control methods employed had permitted the trajectories following by the mobile robot.

Atualmente se observa o incremento exponencial das exigÃncias pela otimizaÃÃo de desempenho em todos os setores da vida moderna. Esta busca por melhor desempenho tambÃm tem ocorrido em todos os setores da indÃstria, seja ela de atividade fabril ou de energia. Melhor desempenho no setor industrial se reflete em melhorias em todos os nÃveis e isto alcanÃa de sobremaneira os sistemas de controle de processos. Com requisitos de desempenho mais rÃgido, tÃcnicas antigamente estudadas somente em meio acadÃmico tem migrado para a indÃstria abrindo novos horizontes e estabelecendo novos conceitos de uma forma geral. Com os sistemas de controle de processos nÃo à diferente e em particular em seu mais baixo nÃvel de implementaÃÃo (chÃo de fÃbrica) tem se observado uma atualizaÃÃo constante. Esta dissertaÃÃo està inserida neste Ãltimo contexto ou seja no projeto das malhas de controle de um sistema de controle de processos. Desta forma aspectos de sintonia de controladores convencionais do tipo PID (Proporcional, Integral, Derivativo) multivariÃveis (MIMO) e controladores MIMO preditivo baseado em modelos do tipo GPC (Generalized Predictive Control) sÃo estudados visando a implementaÃÃo prÃtica. VÃrios aspectos do sistema de controle tais como a identificaÃÃo do processo atravÃs de tÃcnicas paramÃtricas e nÃo paramÃtricas com diferentes representaÃÃes e aspectos do desacoplamento entre as malhas do processo, por se tratar de sistemas MIMO, sÃo tambÃm abordadas, discutidas e implementadas. Para este propÃsito duas plataformas de desenvolvimento foram desenvolvidas no laboratÃrio do NÃcleo de Engenharia ElÃtrica NEEL do IFPI. A primeira plataforma consiste em sistema MIMO de ventilaÃÃo e aquecimento, a segunda plataforma um sistema de tanques duplo acoplados. Como conclusÃo do estudo dos experimentos prÃticos realizados pode-se estabelecer que o melhor controle para um processo depende da aplicaÃÃo ao qual este à destinado e para o bom funcionamento à necessÃrio o conhecimento teÃrico e prÃtico da dinÃmica do processo. Assim um bom controlador depende tambÃm do emprego de uma tÃcnica de identificaÃÃo adequada. / Nowadays, we observe the exponential increasing of demand for performance optimization in all areas of modern life. This search for better performances is also occurring in all industry sectors, either factory or energy activities. This best performances reflects an increase is all levels and achieve enormously the process control systems. With more strict performance requirement, technique formerly studied only in academic circle has been migrate for industry area, opening new horizons and establishing new concepts in general. It is not different with the process control systems, even in particular at the lowest level of implementation (factoryâs floor) has been noted a constantly update. This paper is inserted into this last concept, in other words, into the project of control mesh of process control systems. Thus the aspect of syntony of conventional controllers like PID (Proportional, Integral, Derivative) multivariable (MIMO) and MIMO predictive controllers based on models like GPC (Generalized Predictive Control) type are studied aiming to the practical implementation. Several system control aspects, such as identification of process through parametric and nonparametric technical with different representations and aspects of decoupling between the process meshes, as it is MIMO system, are also dealt, discussed and implemented. For that purpose, two development platforms were developed at IFPIâs NEE (NÃcleo de Engenharia ElÃtrica) laboratory. The first platform consists of MIMO system of ventilation and heating; the second platform is a system of coupled double tanks. As a conclusion of the study of practical experiments conducted, can be established that the best control for a process depends on the application for which it is destined and for the proper functioning is necessary the theoretical and practical knowledge of the dynamic of the process. Thus a proper controller depends also on the use of a technique for proper identification.

The polymer of intrinsic microporosity PIM-1 was synthesized following various procedures: (i) from fluoro-monomer by the conventional method, (ii) from fluoro-monomer by a high temperature, high shear mixing method and (iii) from chloro-monomer. For a more complete understanding of the structure of the resultant products of a series of polymerizations under different reaction conditions, a multi-detector gel permeation chromatography (GPC) method was established and validated. A procedure for fractionating PIM-1 using chloroform methanol solvent mixtures was established and validated. A combination of multi-detector GPC and matrix-assisted laser desorption/ionization-time of flight (MALDI-ToF) masss pectrometry was used for the determination of molar mass distribution and to identify structural differences between fractions and between the products from different synthetic procedures. High molar mass samples tended to have broader molar mass distributions. Both Mark-Houwink plots and hydrodynamic volume plots showed deviation from linearity at Mw= 200000 g mol-1, which was attributed to branching. A low cost route for the preparation of PIM-1 from chloro-monomer was successfully established, though samples prepared by this route had broader polydispersities than those prepared from fluoro-monomers. It was found that stable flexible membranes were formed from samples with Mw > 83000 g mol -1. In addition, a comparison of two analytical methods for extraction and determination of additives in HDPE, LLDPE and PP polymers of interest to Saudi Basic Industries Corporation was performed. A comparison of dissolution with ultrasonic assisted extraction methods for the determination of anti-oxidant additives in polyolefins was performed. Ultrasound assisted extraction methods were found to be superior for HDPE and LLDPE, where conventional dissolution was preferred for PP.

The grape is one of the oldest cultivated plants. It can be consumed as a fruit or it can be used as a raw material for making stews, juices or the cultivated drink – wine. Generations of wine-makers have been striving to improve both the cultivating conditions of vineyards and the quality of wine. Many harmful elements, such as herbivorous pests, diseases and storms are important factors that can have a negative impact on crop quality. To regulate the effects of these factors, an integrated protection system is used, incorporating agronomical measures, resistant varieties and a wide spectrum of pesticides. However, increasing the usage of pesticides brings certain dangers to both the production quality and the environment. This necessitates the monitoring of the negative effects, including the content of pesticide residues in the grapes. My thesis studies and experimentally assesses selected pesticide residues in certain wine samples.

The master's thesis is focused on study of specific protective proteins from animal products. Two different types of antimicrobial egg white proteins were studied in detail - antimicrobial protein ovotransferrin (conalbumin) and enzyme lysozyme. Ovotransferrin belongs to transferrin group of proteins and exhibits activities similar to milk protective protein lactoferrin. The main effects of ovotransferrin are antiviral, anticancer and immunomodulatory. Antimicrobial activity of ovotransferrin based on the possibility to bind iron is still a subject of interest. For comparison the second egg protein lysozyme (N-acetyl muramidglycan hydrolase) was used. Lysozyme is a hydrolytic enzyme which primary attack cell wall of bacteria. In the theoretical part of the thesis an overview of the specific antimicrobial proteins in selected animal products was introduced mainly focused on ovotransferrin and lysozyme. The experimental part of this work was focused on optimization of methods for the determination of antimicrobial activity, protein concentration and purity. For quantitative analysis of total proteins, optimized Hartree – Lowry spectrophotometric method was used. For the determination of molecular weight and purity SDS-PAGE was used and stained by Coomassie Brilliant Blue G250 and silver. In experimental part the real sample of egg white was compared with samples of lyophilized antimicrobial proteins and therapeutical pills supplied by industrial partner. Protein composition and purity of these preparative has been determined. Antimicrobial activity of ovotransferrin was studied on cultures of G+ bacterium Bacillus subtilis and for comparison on G– E. coli. Ovotransferrin showed antimicrobial effect only at very high concentrations of about 75 mg/ml (Bacillus subtilis) and 50 mg/ml (E coli) even with addition of high amount (100 mM) of hydrogen carbonate ions. The inhibitory effect was most evident in liquid media. On the other hand, lysozyme exhibited significant inhibitory activity from 0.3 mg/ml on gram positive bacteria. Inhibitory effect on E. coli was not observed. Another part of study was focused on isolation of ovotransferrin from egg white using gel permeation chromatography on Sephadex G100. As mobile phases 0.1 M phosphate buffer and 0.05 M Tris-HCl buffer were tested. By SDS-PAGE the purity of ovotransferin comparing to standard was evaluated. Finally, the encapsulation of ovotransferrin and lysozyme was tested. Ovotransferrin and lysozyme was encapsulated into liposome and chitosan particles. Particles stability, distribution and average size distribution were studied by dynamic light scattering and zeta potential measurement. The stability of particles in the model physiological conditions was studied too.

Pyrolysis oil is known to be unstable due to polycondensation reactions that negatively affect properties, such as increased viscosity and water content, lower heating values, and phase separation. Filtration of particulates and solid content out of the pyrolysis oil has been proven to increase stability, thus a filtration system was designed for pilot scale testing for the Mississippi State University Sustainable Energy Research Center (SERC). A literature review was conducted to determine potentially effective methods and eliminate methods likely to not improve the pyrolysis oil properties and stability. An in-line centrifuge system was identified as a useful and cost effective way to remove solids from the pyrolysis oil with an added benefit of potentially removing water content through a three-phase separation configuration. Lab-scale testing of centrifugation on pyrolysis oil indicated both two phase (solid + oil phases) and three phase (solid + aqueous phase + oil phases) separations could be obtained depending on feedstock and pyrolysis oil characteristics, and that centrifugation was a viable option for the removal of solid content. KiOR, Inc. pine clear wood derived pyrolysis oil (formerly known as ReCrude™) was characterized to determine physicochemical properties in comparison to literature results. Aging tests were also performed to investigate stability. In comparison with literature data, the properties for the KiOR product indicated significantly lower water content, particulate matter loading, and viscosity coupled with higher heating and pH values, indicating a product much closer in composition to fossil fuel oils than other pyrolysis oils. The KiOR ReCrudeM™ oil also demonstrated a much higher degree of stability versus other pyrolysis oils; however, there are still some stability issues with the aged samples resulting in slightly higher water content and viscosity values and lower heating and pH values. It is recommended that stability testing (aging) be performed on aliquots separated using a method such as rotary evaporation to more accurately determine what mechanisms are resulting in the properties changes observed over time in response to elevated temperature and/or pressure.

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