Hidrólise e caracterização de poliacrilamida hidrofobicamente modificada: avaliação da aplicabilidade na recuperação de petróleo

The hydrolysis reaction in alkaline conditions of the commercial polymer poly(acrylamide-co-metacrylate of 3,5,5-trimethyl-hexane) called HAPAM, containing 0.75 % of hydrophobic groups, was carried out in 0.1 M NaCl and 0.25M NaOH solutions, varying the temperature and reaction time. The polymers were characterized by 1H and 13C Nuclear Magnetic Resonance (NMR), Elemental Analysis and Size Exclusion Chromatography (SEC). The values of the hydrolysis degree were obtained by 13C NMR. The viscosity of HAPAM and HAPAM-10N-R solutions was evaluated as a function of shear rate, ionic strength and temperature. At high polymer concentration (Cp), the viscosity of HAPAM solutions increased with the ionic strength and decreased with the temperature. The viscosity of HAPAM-10N-R solutions increased significantly in distilled water, due to repulsions between the carboxylate groups. At high Cp, with the increase of ionic strength and temperature, occurred a decrease of viscosity, due to mainly the high hydrolysis degree and the low amount of hydrophobic groups. These results indicated that the studied polymers have properties more suitable for the application in Enhanced Oil Recovery (EOR) in low salinity and moderate temperature reservoirs

Caracterização de poliacrilamida parcialmente hidrolisada em regime concentrado

A partially hydrolyzed polyacrylamide (HPAM) is a copolymer composed of acrylamide and sodium acrylate. Due to its wide range of applications there are different methods for its quantification and characterization in solution systems. Evaluation of C* is important to describe the transition from dilute to semi-dilute, behavior, when the solution will have its characteristic viscosity at concentrations above C*. This dissertation describes the determination of the critical concentration of overlap C* by potentiometry of partially hydrolyzed polyacrylamide - HPAM under acidic conditions. Based on the law of mass action and the proper treatment of the constant of aggregate formation, polymer molecular weight, degree of polymerization and hydrolysis were calculated. The inflection point was determined by the intersection of the resulting equation and mathematical development, statistically satisfy the experimental points relating the number of moles of monomers (n), equilibrium constant of formation of the entanglements (K*), pH, C* and acidity constant of the polymer (Ka). The viscometric parameters of C* showed a percentage difference compared to potentiometers. The results for the determination of C*, and degree of copolymerization molar mass proved to be a simple alternative for the characterization of polymers with protonated monomers and water soluble

Síntese e caracterização de poliacrilamidas modificadas para utilização na indústria do petróleo

Modified polyacrylamides with ≅ 0.2 mol % of N,N-dihexylacrylamide and hydrolysis degree from 0 to 25 % were synthesized by micellar copolymerization. The hydrophobic monomer was obtained by the reaction between acryloyl chloride and N,Ndihexylamine and characterized by infrared (IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The polymer molecular structures were determined through 1H and 13C NMR spectroscopy and the polymers were studied in dilute and semi-dilute regimes by viscometry, rheometry, static light scattering and photon correlation spectroscopy, at the temperature range from 25 to 55 ºC. The data obtained by viscometry showed that the intrinsic viscosity from the hydrolyzed polymers is larger than the precursor polymers at the same ionic strength. The comparison between the charged polymers showed that the polymer with higher hydrolysis degree has a more compact structure in formation water (AFS). The increase of temperature led to an enhanced reduced viscosity to the polymers in Milli-Q water (AMQ), although, in brine, only the unhydrolyzed polymer had an increase in the reduced viscosity with the temperature, and the hydrolyzed derivatives had a decrease in the reduced viscosity. The static light scattering (SLS) analyses in salt solutions evidenced a decrease of weight-average molecular weight (⎯Mw) with the increase of the hydrolysis degree, due to the reduction of the thermodynamic interactions between polymer and solvent, which was evidenced by the decrease of the second virial coefficient (A2). The polymers showed more than one relaxation mode in solution, when analyzed by photon correlation spectroscopy, and these modes were attributed to isolated coils and aggregates of several sizes. The aggregation behavior depended strongly on the ionic strength, and also on the temperature, although in a lower extension. The polymers showed large aggregates in all studied conditions, however, their solutions did not displayed a good increase in water viscosity to be used in enhanced oil recovery (EOR) processes

Estudo do mecanismo de produção de oligossacarídeos com atividades nutracêuticas a partir da quitosana por hidrólise enzimática com processo fermentativo simultâneo

The obtaining of the oligosaccharides from chitosanase, has showed interest of the pharmaceutical area in the last years due their countless functional properties. Although, the great challenge founded out is how to keep a constant and efficient production. The alternative proposed by this present work was to study the viability to develop an integrated technology, with reduced costs. The strategy used was the obtaining of the oligomers through enzymatic hydrolysis using chitosanolitic enzymes obtained straight from the fermented broth, eliminating this way the phases involved in the enzymes purification. The two chitosanases producing strains chosen for the work, Paenibacillus chitinolyticus and Paenibacillus ehimensis, were evaluated according to the behavior in the culture medium with simple sugar and in relation to the pH medium variations. The culture medium for the chitosanases induction and production was developed through addition of soluble chitosan as carbon source. The soluble chitosan was obtained using hydrochloric acid solution 0.1 M and afterwards neutralization with NaOH 10 M. The enzymatic complexes were obtained from induction process in culture medium with 0.2% of soluble chitosan. The enzymes production was verified soon after the consumption of the simple sugars by the microorganisms and the maximum chitosanolitic activity obtained in the fermented broth by Paenibacillus chitinolyticus was 249 U.L-1 and by Paenibacillus ehimensis was 495U.L-1. These two enzymatic complexes showed stability when stored at 20°C for about 91 days. The enzymes in the fermented broth by Paenibacillus chitinolyticus, when exposed at temperature of 55°C and pH 6.0, where the activity is maximum, showed 50% lost of activity after 3 hours Meanwhile, for the complex produced by Paenibacillus ehimensis, after 6 days of exposure, it was detected 100% of the activity. The chito-oligosaccharides obtained by the hydrolysis of a 1% chitosan solution, using the enzymatic complex produced by Paenibacillus chitinolyticus showed larger quantity after 9 hours hydrolysis and using the complex produced by Paenibacillus ehimensis after 20 minutes was observed the chito-ligosacharides with polymerization degree between 3 and 6 units. Evaluating these results, it was verified that the production of chitosan-oligosaccharides is possible, using a simultaneous process

Biblioteca Digital de Teses e Dissertações: grau de utilização pelos mestrandos do curso de Ciência da Informação das Universidades Públicas Brasileiras

A pesquisa aborda o uso das Tecnologias de Informação e Comunicação, que vem revolucionando as atividades e ocasionando muitas mudanças relacionadas ao acesso e uso de informações. O objetivo foi analisar o grau de utilização do conhecimento científico produzido pelos Programas de Pós-Graduação das Universidades Públicas Brasileiras, através da BDTD, pelos mestrandos dos referidos programas. Nos procedimentos metodológicos realizados, procurou-se inicialmente analisar o amplo espectro da população do corpus da pesquisa. Em razão da impossibilidade de trabalhar com os Programas de Pós-Graduação como um todo, optou-se por fazer um recorte, elegendo os cursos de Pós-Graduação em Ciência da Informação, vez que estes representam o principal segmento social de interesse da pesquisa. Foi utilizado o método de estudo de usuários, onde se optou por adotar o grupo, “estudos orientados aos usuários”, que identifica as necessidades e comportamento de acesso e uso da informação. Para coletar os dados, elaborou-se um questionário semi-estruturado com 25 questões, que versavam sobre o uso, dificuldades de acesso e recuperação da informação, bem como a satisfação na utilização dessa fonte informacional. Dentre os vários resultados obtidos, podemos destacar o fato de que a maioria dos mestrandos (71,8%) só teve contato com a BDTD somente no momento em que se encontrava cursando o mestrado e, somente 24,3%, tiveram contato durante a graduação. Estes resultados representam um problema, que pode afetar o bom desempenho do projeto BDTD, o qual consiste em disseminar e divulgar a produção científica dos Programas de Pós-Graduação das Universidades Públicas Brasileiras para a sua comunidade. Foi observado também, que os mestrandos oriundos do curso de Biblioteconomia tende a ter contato com a BDTD bem mais cedo do que mestrandos de outros cursos de graduação. A fim de minimizar o problema detectado, propõe-se uma divulgação mais eficaz na graduação através de dois procedimentos: Primeiro, o docente deve fazer uma divulgação mais eficaz da BDTD junto aos discentes de todos os cursos de graduação; segundo: deverá ser feita a divulgação na mídia eletrônica, através da inserção de ícones da BDTD, nos portais dos Departamentos dos Cursos de Graduação das Universidades Públicas Brasileiras. Acredita-se que com estes procedimentos seja possível aperfeiçoar o uso dessa fonte de informação científica.

Purificação e caracterização de uma β-glucuronidase extraída do molusco mesogastropoda ampularidade Pomacea sp

This work studies the involved enzymatic way in the metabolism of glycosaminoglycans sulfateds in the mollusc Pomacea sp. Had been identified endoglycosidases and exoglycosidases in the enzymatic extract of the mollusc Pomacea sp by means of hydrolysis activity in condroitim sulphate of whale cartilage and of the p-Nitrofenil-β-glucuronide, respectively. The enzymatic extracts qere obtained of Pomacea sp. being used of 0.1 sodium acetate buffer, pH 5.0 and later centrifugated the 8,000 x g and the presents proteins in the sobrenadante were submitted to the fractionament with two crescents ammonium sulphate concentrations, the visualized activity biggest in the F2 fraction (50-80%). The β-glucuronidase (F3) was isolated in gel chromatography filtration Biogel 1.5m, the purification degree was ratified in Chromatography Liquid of high efficiency (HPLC). The enzyme was purificated 6.362,5 times with 35,6% yield. The β -glucuronidase isolated in this work showed a molecular mass of 100 kDa, determined for eletroforese in poliacrilamida gel . The determination of the ideal kinetic parameters for the catalysis of the p-nitrofenil- β -glucuronide for β-glucuronidase, showed excellent activity in pH 5,0 and temperature 65ºC for 6 hours and apparent Km of 72 x 10-2 mM. It is necessary for the total degradation of 3mM of p-N-β-glucoronide, the amount of 1,2μg of ss-glucuronidase. The BaCl2 increased the activity of ss-glucuronidase, and the activity was inhibited completely by the composites SDS and NaH2PO4

O tratamento ortodôntico em uma perspectiva a longo prazo: avaliação da estabilidade oclusal e do grau de satisfação dos pacientes

This study aimed to evaluate factors associated to orthodontic treatment stability and patient satisfaction in the long-term. A total of 209 patients (88 class I and 121 class II) treated with straight wire fixed appliance were selected at least 5 years post treatment. Six hundred twenty seven dental casts were examined with the PAR Index at pretreatment (T1), end of treatment (T2), and at long-term follow up (T3, mean 8.5 years post treatment). At T3, a Dental Impact on Daily Living questionnaire was used to assess patient satisfaction with the dentition in the long-term. Friedman test and multiple regression analysis were used to evaluate changes among the time points and factors associated with stability and patient satisfaction. Predictive factors used to exam the occlusion were: PAR Index at T1 and T2, age at T1, the amount of time without retainer, length of Hawley retainer wear, length of follow-up, sex, extraction and third molar status. To assess patient satisfaction were considered: changes produced by the orthodontic treatment (PAR T2-T1), post treatment stability (PAR T3), age at the start of treatment (T1), length of treatment (T2-T1), gender, and extraction. Orthodontic treatment produced a significant improvement of 94.2% in the PAR Index (T2-T1), but this change was not associated with the level of satisfaction when the patient was questioned at T3. No significant change was observed between T2 and T3. However, when the sample was divided according to the level of finalization (PAR T2), it was observed that well-finished patients experienced some deterioration (P<.001), whereas the less well-finished ones showed some improvement (P<.05). Even with the deterioration, the well-finished patients still had a better PAR Index at T3 compared to the less well-finished ones (PAR T2- T3). Regression analysis showed that PAR Index at T1 and T2, age at T1, and length of retainer wear had a slight association with occlusal stability (R2 = 0.27). Patient satisfaction was significantly associated only with PAR Index at T3 (r2=0.125, P<.0001). We can conclude that, even thought orthodontic treatment is quite stable, not so well-finished treatments tend to show some improvement and well-finished ones deteriorate some in the long-term. Despite of that, well-finished patients still have better occlusal characteristics. Patient satisfaction is not related to the result of orthodontic treatment; nevertheless, there is a slight association with dentition in the long-term

A legitimidade da jurisdição de primeiro grau na concretização dos direitos fundamentais: proposta de um novo modelo jurídico-administrativo para o segundo grau de jurisdição

The current study is about the legitimacy of lower court jurisdiction as a way of exercising basic legal rights, proposing, therefore, a new legal-administrative model for appellate court. In order to achieve that, a demonstration of the importance of basic legal rights in the Brazilian legal system and an open interpretation in light of the Constitution, as a way to affirm said rights, among which are accessibility to the justice system and proper legal protection, is required. As a result, the legitimacy to access the legal system resides in the Constitution, where the interpreter should seek its basic principles to achieve basic legal rights. It is observed that the lack of credibility regarding lower court decisions comes from the dogmatic view of truth born from power, and therefore, that the truth resides in decisions from appellate court and not from lower court judges. A lower court judge holds a privileged position in providing basic legal rights for citizens, considering his close contact to the parties, the facts, and the evidences brought forth. Class action suit is presented as an important instrument able to lead the lower court judge to provide basic legal rights. Small Claims Courts may be used as paradigm to the creation of Appellate State Courts formed by lower court judges, reserving to higher jurisdiction courts and Federal Circuit Courts, the decisions of original competency and the management and institutional representation of the judiciary system. Instilling an internal democratization of the judiciary is also required, which means the participation of lower court judges in electing their peers to chief positions in the court system, as well as establishing a limited mandate to higher court judges.

Utilizando processos geométricos da história da matemática para o ensino de equações do 2º grau

The present work had as principal objective to analyze the, 9th grade students understanding about the solutions of an equation of the 2° degree, using geometric processes of the History of the Mathematics. To do so, the research had as base the elaboration and application of a group of teaching activities, based on Jean Piaget's construtivism. The research consisted of a methodological intervention, that has as subjects the students of a group of 9th grade of the State School José Martins de Vasconcelos, located in the municipal district of Mossoró, Rio Grande do Norte. The intervention was divided in three stages: application of an initial evaluation; development of activities‟ module with emphasis in constructive teaching; and the application of the final evaluation. The data presented in the initial evaluation revealed a low level of the students' understanding with relationship to the calculation of areas of rectangles, resolution of equations of the 1st and 2nd degrees, and they were to subsidize the elaboration of the teaching module. The data collected in the initial evaluation were commented and presented under descriptive statistics form. The results of the final evaluation were analyzed under the qualitative point of view, based on Richard Skemp's theory on the understanding of mathematical concepts. The general results showed a qualitative increase with relationship to the students' understanding on the mathematical concepts approached in the intervention. Such results indicate that a methodology using the previous student‟s knowledge and the development of teaching activities, learning in the construtivist theory, make possible an understanding on the part of the students concerning the thematic proposal

Responsabilidade social empresarial: modalidades e grau de participação em meios de hospedagem em Ponta Negra, Natal/RN

That work has as objective to investigate and to analyze the strategies which they were developed by companies of lodging means with ends of social responsibility in Rio Grande do Norte (RN). Therefore, it got data along with the Office of Tourism of the Municipal district of Natal , the Office of Tourism of RN and the cadasters of the firms of the lodging means in the district of Ponta Negra. In after research of field, it verified the enterprises that now develop lodging activities in that quarter in Ponta Negra. It applied Instrument of research which it was elaborated based on the set of indicators of social responsibility of Ethos Institute, structured with binary questions and some open ones. It shows as results which actions the investigated companies develop. Confronting these results with researched theoretical referencial, it points an intermediate degree of socially responsible actions. Comparing with the evaluation accomplished by Ethos Institute, the investigated firms are in incipient condition, with punctual actions, however, they already present the awakening about this thematic

A influência do modelo de triplice hélice no grau de maturidade de inovação: um estudo de caso em empresas participantes do projeto PRÓ-INOVA/NAGI no estado do RIO GRANDE DO NORTE

Public investments in the development of innovation in the country, either through the rigging of public universities, either through public announcements of the promotion, increased dramatically in recent years. To analyze the efficiency and effectiveness of the use of public resources is especially in times of austerity, essential for the development of a country. In this context, this research aims to identify the influence of public investments to promote innovation in the degree of maturity of innovative companies in the state of the RN. Another goal is to identify the regional influence from the installation site - capital or countryside, in the performance of the companies studied in the degree of innovation. The theoretical basis of the understanding of the scope of the concept of innovation and its determination for the purposes of this study. Typology, degree of innovation, evaluation methodologies and mechanisms to support innovation : Still on the theme of innovation additional concepts that help the reader to a greater understanding, such as are presented. Following is approached conceptualization of the triple helix, highlighting the concepts advocated by Etzkowitz and Leydesdorff, Salomon and Silva and Ipiranga, Freitas and Paiva, among others. With regard to methodological aspects, we propose a descriptive, exploratory and explanatory research quantitative and qualitative approach with the target audience group of companies served by INOVA PRO- NAGI design - multi-institutional action from a public resource called FINEP promotes the development of innovative companies in the State of Rio Grande do Norte - in 2013. The research should provide reflection and understanding of the influence of public investment in innovation, which by means of qualitative predictive variables associated with quantitative method to explain which variables are significant variations in the degree of maturity of enterprises studied

Hidrólise de resíduos lignocelulósicos utilizando extrato enzimático celulolítico produzido por Trichoderma reesei atcc 2768

Cellulolytic enzymatic broth by Trichoderma reesei ATCC 2768 cultived in shaker using cashew apple bagasse and coconut shell bagasse, as substrate for fermentation, was used to investigate the enzymatic hydrolysis of these substrates after pre-treatment with 1 M NaOH, wet-oxidation as well as a combination of these treatments. Hydrolysis runs were carried at 125 rpm, 50ºC and initial pH of 4.8 for 108 hours. Enzymatic broth produced using cashew apple bagasse treated with 1M NaOH (1.337 UI/mL CMCase and 0.074 UI/mL FPase), showed after the hydrolysis an initial of 0.094 g of reducing sugar/g of substrate.h with 96% yield of total reducing sugars while for the coconut shell bagasse treated using the alkaline process (0.640 UI/mL CMCase and 0.070 UI/mL FPase) exhibited an initial hydrolysis velocity of 0.025 g of reducing sugar/g of substrate.h with 48% yield of total reducing sugars. For the treatment with wet-oxidation using cashew apple bagasse as substrate enzymatic broth (0.547 UI/mL CMCase) exhibited an initial hydrolysis velocity of 0.014 g of reducing sugars/g of substrate.h with a lower yield about 89% of total reducing sugars compared to the alkaline treatment. Enzymatic broth produced using coconut shell treated by wet-oxidation showed an initial hydrolysis velocity of 0.029 g of reducing sugar/g of substrate.h with 91% yield. However, when the combination of these two treatments were used it was obtained an enzymatic broth of 1.154 UI/mL CMCase and 0.107 FPase for the cashew apple bagasse as well as 0.538 UI/mL CMCase and 0,013 UI/mL de FPase for the coconut shell bagasse. After hydrolysis, initial velocity was 0.029 g of reducing sugar/g of substrate.h. with 94% yield for the cashew apple bagasse and 0.018 g de reducing sugar/g of substrate.h with 69% yield for coconut shell bagasse. Preliminary treatment improves residues digestibility showing good yields after hydrolysis. In this case, cellulose from the residue can be converted into glucose by cellulolytic enzymes that can be used for ethanol production

Uma sequencia didática para o ensino da resolução da equação do 2. grau : adequação para o uso com professores

The present study aims to check whether the use of activities mediated by the History of Mathematics can contribute to improve the understanding of resolution the 2nd degree equation for teachers and undergraduates that reproduce methods of solving such equations, uncritically, without domain of the justifications for their actions. For this, we adapted a didactic sequence with activities that aims to cause a rediscovery of resolutive formula of 2nd degree equation through the method known as cut and paste. Finally, we presented the activity module containing the didactic sequence used during the study, as suggestion for use in the classroom, by the math teacher

Grau de conhecimento de pacientes sobre o acidente vascular cerebral e a necessidade do uso de cartilha educativa para orientação fisioterapêutica

Stroke is a neurological dysfunction of vascular origin that causes physical impairments and disabilities. Brazil leads the statistics stroke mortality among Latin American countries, demonstrating still be a neglected disease in this country. The incidence is related to risk factors and still is great misinformation in our country about stroke, treatment and prophylaxis. The aim of this study was to assess the degree of knowledge about stroke and patients need to use educational booklet for physiotherapy. The sample consisted of 53 patients, 22 females and 31 males, mean age 56.2 ± 10.9 years. Patients were evaluated by completing questionnaires, observing the socio-demographic and clinical aspects, neurological assessment, functional assessment, knowledge of pathology and presenting educational booklet. The data were analyzed using the chi-square test. According to the results, it was observed that the patients had not enough knowledge about the terminology, complications and warning signs of stroke, were not aware and did not perform the proper positioning of the limb and transfers, however, were aware and performed the stretching maneuvers. This reveals the need to implement policies that lead to information about stroke population. Following discharge from outpatient physical therapy using educational booklets with guidelines on positioning, stretching exercises and transfer is important in functional rehabilitation and encouraging independence of the individual affected by stroke

Estudo da imobilização de proteases para a síntese de oligolisinas

Enzymatic synthesis of peptides using proteases has attracted a great deal of attention in recent years. One key challenge in peptide synthesis is to find supports for protease immobilization capable of working in aqueous medium at high performance, producing watersoluble oligopeptides. At present, few reports have been described using this strategy. Therefore, the aim of this thesis was to immobilize proteases applying different methods (Immobilization by covalent bound, entrapment onto polymeric gels of PVA and immobilization on glycidil metacrylate magnetic nanoparticles) in order to produce water-soluble oligopeptides derived from lysine. Three different proteases were used: trypsin, α-chymotrypsin and bromelain. According to immobilization strategies associated to the type of protease employed, trypsin-resin systems showed the best performance in terms of hydrolytic activity and oligopeptides synthesis. Hydrolytic activities of the free and immobilized enzymes were determined spectrophotometrically based on the absorbance change at 660 nm at 25 °C (Casein method). Calculations of oligolysine yield and average degree of polymerization (DPavg) were monitored by 1H-NMR analysis. Trypsin was covalently immobilized onto four different resins (Amberzyme, Eupergit C, Eupergit CM and Grace 192). Maximum yield of bound protein was 92 mg/g, 82 mg/g and 60 mg/g support for each resin respectively. The effectiveness of these systems (Trypsin-resins) was evaluated by hydrolysis of casein and synthesis of water-soluble oligolysine. Most systems were capable of catalyzing oligopeptide synthesis in aqueous medium, albeit at different efficiencies, namely: 40, 37 and 35% for Amberzyme, Eupergit C and Eupergit CM, respectively, in comparison with free enzyme. These systems produced oligomers in only 1 hour with DPavg higher than free enzyme. Among these systems, the Eupergit C-Trypsin system showed greater efficiency than others in terms of hydrolytic activity and thermal stability. However, this did not occur for oligolysine synthesis. Trypsin-Amberzyme proved to be more successful in oligopeptide synthesis, and exhibited excellent reusability, since it retained 90% of its initial hydrolytic and synthetic activity after 7 reuses. Trypsin hydrophobic interactions with Amberzyme support are responsible for protecting against strong enzyme conformational changes in the medium. In addition, the high concentration of oxirane groups on the surface promoted multi-covalent linking and, consequently, prevented the immobilized enzyme from leaching. The aforementioned results suggest that immobilized Trypsin on the supports evaluated can be efficiently used for oligopeptides synthesis in aqueous media