28 resultados para Catalisis, Heterogénea
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
A síndrome dos ovários policísticos (SOP) é um distúrbio endócrino-ginecológico que se caracteriza, principalmente, por anovulação crónica e hiperandrogenismo, afetando entre 5 a 10% das mulheres em idade reprodutiva. As principais manifestações da SOP incluem os seguintes sintomas: irregularidade menstrual, hirsutismo, infertilidade, acne, alopecia androgenética, obesidade e acantose nigricans. Esses sintomas apresentam- se de forma bastante heterogênea, havendo diferenças marcantes na sua prevalência e intensidade entre diferentes grupos de mulheres que apresentam SOP. Apesar da condição biológica, a SOP não é apenas um problema físico, mas também psicossocial, interferindo e comprometendo a qualidade de vida das mulheres que a apresentam. A partir de uma revisão da literatura, este estudo discute os aspectos psicossociais de mulheres com SOP, destacando o impacto dos sintomas na qualidade de vida relacionada com a saúde. Considerando que cada mulher responde de forma singular aos sintomas que apresentam, destaca-se a importância de incorporar a perspectiva individual da mulher com SOP ao seu contexto social. Nesse sentido, são discutidos achados de pesquisas utilizando abordagens metodológicas quantitativas e qualitativas, numa tentativa de melhor compreender a experiência das mulheres diante da SOP. Os sintomas da SOP podem estar associados com a ocorrência de ansiedade, disfunções sexuais e sentimentos de inadequação ao papel feminino, como também podem desencadear sintomas depressivos e isolamento social, com comprometimento significativo da qualidade de vida. Os autores destacam a importância do atendimento multidisciplinar para as mulheres com SOP, considerando essa condição como importante problema psicossocial. A atenção aos aspectos psicossociais da SOP tem aumentado nos últimos anos, no entanto, a produção científica relacionada ainda é escassa
Resumo:
Biodiesel is an alternative fuel, renewable, biodegradable and nontoxic. The transesterification of vegetable oils or animal fat with alcohol is most common form of production of this fuel. The procedure for production of biodiesel occurs most commonly through the transesterification reaction in which catalysts are used to accelerate and increase their income and may be basic, acid or enzyme. The use of homogeneous catalysis requires specific conditions and purification steps of the reaction products (alkyl ester and glycerol) and removal of the catalyst at the end of the reaction. As an alternative to improve the yield of the transesterification reaction, minimize the cost of production is that many studies are being conducted with the application of heterogeneous catalysis. The use of nano-structured materials as catalysts in the production of biodiesel is a biofuel alternative for a similar to mineral diesel. Although slower, can esterify transesterified triglycerides and free fatty acids and suffer little influence of water, which may be present in the raw material. This study aimed at the synthesis, characterization and application of nano-structured materials as catalysts in the transesterification reaction of soybean oil to produce biodiesel by ethylic route. The type material containing SBA-15 mesoporous lanthanum embedded within rightly Si / La = 50 was used catalyst. Solid samples were characterized by X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, nitrogen adsorption and desorption. For the transesterification process, we used a molar ratio of 20:1 alcohol and oil with 0.250 g of catalyst at 60°C and times of 6 hours of reaction. It was determined the content of ethyl esters by H-NMR analysis and gas chromatography. It was found that the variable of conversion obtained was 80%, showing a good catalytic activity LaSBA-15 in the transesterification of vegetable oils via ethylic route
Resumo:
The relation between State and civil society is not a very recent discussion, but it does not mean that debate is exhausted, since is in the historical context that the novelty is seized. Thinking like this, we may analyze how the relation between state and civil society happened in Acre during the decade of 1970. But, to understand how this relation is established in faraway Acre, we have available to the reader historical analyses, in a tireless attempt to clarify minimally aspects that characterize acreana society. To do this, we take on as a departure point, in general not differentiating of the given structure at national level, the conformation of this society was guided in a passive revolution, in another way, by high transformismo, relegating to the civil society, which is incipient, pífia a simple participation in the hegemonic policy direction. All this brings us to the thought that both state bureaucracy structure and the civil society organization, were influenced decisively for a traditional political elite. In addition, we begin the work with the lifting bibliographic reference searching and then we analyze the empirical reality, such as newspapers, official media publications and private, a few documents and last, interviews with political actors associated with the process consolidation of civil society in the 1970 decade. The interviewees were selected, firstly for their location in the region, and for their outstanding contribution to the consolidating process of recent Acre history. Thus, the interviews followed up on a semi-structured way, leading up, also, for the informations that the interviewees would have to pass on. The systematization and analysis of these surveys have shown us that, in the period before of the Acre Federal State lifting had, of course, a transformismo by high, but at 1970decade, the society with a more heterogeneous social formation, is not allowed, or at least, organize itself, to counter a systematic imposition. Thus, the hegemonic area of dispute between State and civil society occurs from the "reconciliation" with the adoption of public policies that amenizasse the dispute between both spheres, and to build up some bodies, settling a acreana civil society.
Resumo:
The neoconstitutionalism led to a process of ethical revaluation of the normative systems and the process of constitutionalization of the many fields of law. This study examines the consequences of this process in criminal law, so important a Law field for the protection of the most valuable assets by the society, including the fundamental guarantees, thus emphasizing the necessity of protection of the collective and individual rights, which are guided by the observance of the defendants individual rights in the course of criminal proceedings and the search for the best efficiency of penal protection, according to the corollaries of defense against the state (prohibition of the excess or Übermassverbot) and the provision of rights by the state (prohibition of insufficient protection or Untermassverbot). The offense of fuel adulteration is taken as an object of study, since it is a vital market to a nation dependent of people and good s movement for their living, driven by fossil and biofuels. Such a crime affects essential legal interests to the development of society, interests such as the environment, consumer relations and economic order, particularly the principle of free competition. This paper seeks to analyze the need of a greater efficiency of this particular criminal protection, once concluded the conduct harm and social fear as a consequence by it as growing, and therefore having its former crime type, engraved in Article 1 of Law No. 8.176/1991, rewritten in compliance with the criminal law s principle of legality. Thus, the reformation proposals and legislative creation involving this crime were observed, with emphasis on the bill No. 2498/2003, which keeps it as blank heterogeneous criminal norm, kind of penal normative whose constitutionality is raised, including the forethought of criminal responsibility in the perpetrating of the offense as culpable and subsequently increasing the applicable minimum penalty, as well as the inclusion of new activities in the typical nucleus
Resumo:
This thesis entitled, Attention, Consciousness and Practice of Teaching: A Study of its Interconnects, argues about a relationship between development of attention and consciousness and its connection to the pedagogical practice developed in a public elementary school in Natal city, Rio Grande do Norte state. The research school is located in the south of the city. School activities are developed according with the political pedagogical project. The group investigated was 25 students aged between 8-12 years of the fourth grade. The students of the research are residents of Ponta Negra village, Pirangi and Neópolis districts. The research was effected by three teachers however, the purpose of this thesis was to investigate the relationship between the development of attention and awareness and the pedagogical practice of one of the teachers who participated in the research, and more specifically understand the psychic procedures involved in the development of attention and awareness; enabling conditions for the realization of an educational action that enables the development in terms of focused attention and states of consciousness of students, analyzing their interrelations. Therefore, it was used as methodology the collaborative research by providing elements for research as strategy of formation and development, the coproduction of knowledge, and the change of educational practice through reflective processes effected through the collaboration and critical reflection among participants. For empirical construction, it was used the following procedural elements: meeting, planning, diagnosis of attention and awareness, reflective period studies, collaborative observation and reflection sessions with the participant teachers and the students. The diagnosis of attention was effected through a game and its elaboration was based on the study proposed by Luria (1991). The purpose of the game was to apprehend the stage where students were in relation of a development attention. Concerning the diagnosis of consciousness, it was taken as reference studies by Burlatski (1987), Pinto (1960a, 1960b), Rubinstien (1973), Leontiev (1978) and others studies discussing this topic. As a method of analysis, it was resorted to the dialectical historical materialism, the ability to identify, analyze and explain those contradictions generated in the process. In the analysis procedures were prepared some categories as well as, were used categories by other authors with the purpose of understanding the critical reflective process collaborative evidencing the formation of concepts and pedagogical practice of the participants, and the analysis of a practical pedagogical of a teacher and her relationships with the development of the psychic process and functions of students, in other words, attention and awareness. Regarding the reflective process were used the categories: technical reflection, critical reflection and practical reflection (LIBERALI, 2008). Concerning the analysis of the concepts were used the categories: description, characterization, definition and conceptualization (FERREIRA, 2003). And for critical collaboration were the categories: critical collaboration, uncritical, technique and practice. In pedagogical practice, were used categories: repetitive practice teaching, heterogeneous and reflexive critical (SOUZA, 2010). During the collaborative observation was evident predominance of heterogeneous practice, because the main participant teacher searches for immediate solution to the situations problem, as well as reflection moments, is the technical arrangement, practice, critical, as well as concern in interacting with students, the qualitative changes, deep knowledge, renewal and transformation of the teaching activity. In this process, the collaborative reflection proved to be an effective strategy for developing awareness of students, because through reflection sessions, the students were able to understand that learning is a building process and that it necessary to be careful for their development
Resumo:
At the current time of demographic changes in the world , it is observed that the health sector requires restructuring of its practices in caring for the elderly , in order to enable a comprehensive and humane care . In this sense, we identify the need for qualified professionals to assist the elderly and, therefore , it is important that training curricula are adequate to this reality . The study aims to analyze how it develops teaching gerontological nursing component in undergraduate nursing . This is a descriptive , exploratory study with a qualitative approach, in two higher education institutions in the city of Natal / RN . The population involved corresponded to the coordinators of graduate courses in nursing and teachers who teach content of health care for the elderly, a total of seven participants . The data collection instruments were used: a questionnaire containing questions related to the characterization of the participants and the teaching of gerontological nursing in undergraduate courses in nursing and a form with items of analysis for pedagogical projects . The results were presented descriptively in tables and analyzed from coming themes of the main themes of the instruments defined in: knowledge about the research participants , knowledge of teaching gerontological nursing component and knowledge of pedagogical projects , discussed under Resolution paragraph . 03 of 7/11/2001 , which establishes standards for the nursing program , the educational projects of educational institutions , the Theoretical Donald Shoon and thematically relevant literature . The results indicate that the majority of participants were female (four), all have graduate though , none of them stated in the qualification of aging or elderly health area; the organization of the contents of the component in the curriculum, workload theoretical- methodological and practical teaching strategies presented was heterogeneous and sometimes diverging at the same institution . On the definition of gerontological nursing component was identified that is not well defined along the pedagogical design of educational institutions surveyed . It was concluded that in the context of this study , teaching gerontological nursing is present in the course of nursing education, but needs reevaluation and updating in order to teach a wider range of driving and health practices
Resumo:
Nowadays, classifying proteins in structural classes, which concerns the inference of patterns in their 3D conformation, is one of the most important open problems in Molecular Biology. The main reason for this is that the function of a protein is intrinsically related to its spatial conformation. However, such conformations are very difficult to be obtained experimentally in laboratory. Thus, this problem has drawn the attention of many researchers in Bioinformatics. Considering the great difference between the number of protein sequences already known and the number of three-dimensional structures determined experimentally, the demand of automated techniques for structural classification of proteins is very high. In this context, computational tools, especially Machine Learning (ML) techniques, have become essential to deal with this problem. In this work, ML techniques are used in the recognition of protein structural classes: Decision Trees, k-Nearest Neighbor, Naive Bayes, Support Vector Machine and Neural Networks. These methods have been chosen because they represent different paradigms of learning and have been widely used in the Bioinfornmatics literature. Aiming to obtain an improvment in the performance of these techniques (individual classifiers), homogeneous (Bagging and Boosting) and heterogeneous (Voting, Stacking and StackingC) multiclassification systems are used. Moreover, since the protein database used in this work presents the problem of imbalanced classes, artificial techniques for class balance (Undersampling Random, Tomek Links, CNN, NCL and OSS) are used to minimize such a problem. In order to evaluate the ML methods, a cross-validation procedure is applied, where the accuracy of the classifiers is measured using the mean of classification error rate, on independent test sets. These means are compared, two by two, by the hypothesis test aiming to evaluate if there is, statistically, a significant difference between them. With respect to the results obtained with the individual classifiers, Support Vector Machine presented the best accuracy. In terms of the multi-classification systems (homogeneous and heterogeneous), they showed, in general, a superior or similar performance when compared to the one achieved by the individual classifiers used - especially Boosting with Decision Tree and the StackingC with Linear Regression as meta classifier. The Voting method, despite of its simplicity, has shown to be adequate for solving the problem presented in this work. The techniques for class balance, on the other hand, have not produced a significant improvement in the global classification error. Nevertheless, the use of such techniques did improve the classification error for the minority class. In this context, the NCL technique has shown to be more appropriated
Resumo:
Among the heterogeneous catalysts materials made from niobium show up as an alternative to meet the demand of catalysts for biodiesel production. This study aims to evaluate the potential of a heterogeneous catalyst derived from a complex of niobium in the reaction of methyl esterification of oleic acid. The catalyst was synthesized after calcination at different temperatures of a niobium complex ((NH4)3[NbO(C2O4)3].H2O) generating a niobium oxide nanostructure with a different commercial niobium oxide used to synthesize the complex. The commercial niobium oxide, the complex niobium and niobium catalyst were characterized by thermogravimetry (TG and DTA), surface area analysis (BET), scanning electron microscopy (SEM) and X-ray diffraction (XRD), showing the catalyst has researched morphological and crystallographic indicating a catalytic potential higher than that of commercial niobium oxide characteristics. Factorial with central composite design point, with three factors (calcination temperature, molar ratio of alcohol/oleic acid and mass percentage of catalyst) was performed. Noting that the optimal experimental point was given by the complex calcination temperature of 600°C, a molar ratio alcohol/oleic acid of 3.007/1 and the catalyst mass percentage of 7.998%, with a conversion of 22.44% oleic acid in methyl oleate to 60 min of reaction. We performed a composite linear and quadratic regression to determine an optimal statistical point of the reaction, the temperature of calcination of the complex at 450°C, the molar ratio of alcohol/oleic acid 3.3408/1 and mass percentage of catalyst of 7.6833% . Kinetic modeling to estimate parameters for heterogeneous catalysis it set well the experimental results with a final conversion of 85.01% with 42.38% of catalyst and without catalyst at 240 min reaction was performed. Allowing to evaluate the catalyst catalytic studied has the potential to be used in biodiesel production
Resumo:
The petroleum industry deals with problems which are difficult to solve because of their relation to environmental issues. This is because amounts of residue are generated which vary in type and danger level. The soil contamination by non aqueous liquid phase mixtures, specifically hydrocarbon petroleum has been a reason for great concern, mainly the aromatic and polycyclic aromatic, which present risk to human health due to its carcinogenic and mutagenic character. The Advanced Oxidative Processes (AOP) are efficient technologies for destruction of organic compounds of difficult degradation and, often, they are present in low concentrations. They can be considered clean technologies, because there is no formation of solid by-products or the transfer of pollutor phases. This work focuses on the study of the degradation of petroleum industrial waste, by Advanced Oxidation Processes. Treatments tackling petroleum residues, contaminated soil, and water occurring in the production of petroleum reached the following Polycyclic Aromatic Hydrocarbons (PAH) degradation levels: solid residues 100% in 96 treatment hours; water residue - 100% in 6 treatment hours; soil contamination (COT degradation) - 50.3% in 12 treatment hours. AOP were effective in dealing with petroleum residues thus revealing themselves to be a promising treatment alternative
Resumo:
The wet oxidation of organic compounds with CO2 and H2O has been demonstrated to be an efficient technique for effluent treatment. This work focuses on the synthesis, characterization and catalytic performance of Fe-MnO2/CeO2, K-MnO2/CeO2/ palygorskite and Fe/ palygorskite toward the wet oxidative degradation of phenol. The experiments were conducted in a sludge bed reactor with controlled temperature, pressure and stirring speed and sampling of the liquid phase. Experiments were performed on the following operating conditions: temperature 130 ° C, pressure 20.4 atm, catalyst mass concentration of 5 g / L initial concentration of phenol and 0.5 g / L. The catalytic tests were performed in a slurry agitated reactor provided with temperature, pressure and agitation control and reactor liquid sampling. The influences of iron loaded on the support (0.3; 7 and 10%, m/m) and the initial pH of the reactant medium (3.1; 6.8; 8.7) were studied. The iron dispersion on the palygorskite, the phase purity and the elemental composition of the catalyst were evaluated by X-Ray Difraction (XRD), Scanning Electron Microscopy (SEM) and X-Ray Flourescence (XRF). The use of palygorskite as support to increase the surface area was confirmed by the B.E.T. surface results. The phenol degradation curves showed that the Fe3+ over palygorskite when compared with the other materials tested has the best performance toward the (Total Organic carbonic) TOC conversion. The decrease in alkalinity of the reaction medium also favors the conversion of TOC. The maximum conversion obtained from the TOC with the catalyst 3% Fe / palygorskite was around 95% for a reaction time of 60 minutes, while reducing the formation of acids, especially acetic acid. With products obtained from wet oxidation of phenol, hydroquinone, p-benzoquinone, catechol and oxalic acid, identified and quantified by High Performance Liquid Chromatography was possible to propose a reaction mechanism of the process where the phenol is transformed into the homogeneous and heterogeneous phase in the other by applying a kinetic model, Langmuir-Hinshelwood type, with evaluation of kinetic constants of different reactions involved.
Resumo:
In this thesis we study some problems related to petroleum reservoirs using methods and concepts of Statistical Physics. The thesis could be divided percolation problem in random multifractal support motivated by its potential application in modelling oil reservoirs. We develped an heterogeneous and anisotropic grid that followin two parts. The first one introduce a study of the percolations a random multifractal distribution of its sites. After, we determine the percolation threshold for this grid, the fractal dimension of the percolating cluster and the critical exponents ß and v. In the second part, we propose an alternative systematic of modelling and simulating oil reservoirs. We introduce a statistical model based in a stochastic formulation do Darcy Law. In this model, the distribution of permeabilities is localy equivalent to the basic model of bond percolation
Resumo:
Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region
Resumo:
One of the Psychology challenges, especially among the assessment and educational areas, is to understand and predict individual differences. In this context, this research aimed to verify the personality styles of students with high and low academic performance. The study included 236 university students from Petrolina-PE and Juazeiro-BA campus of the UNIVASF (Universidade Federal do Vale do São Francisco). They were uniformly distributed in four disciplines (medicine, psychology, administration and civil engineering), 10 students from each semester (five highest scores average students and five lowest scores average students) took place of the sample. The Millon Index Personality Styles (MIPS) was applied to analyze the personality/behavioral styles of the students. The MIPS is a 180 dichotomous (true/false) item scale. It was also developed and applied a questionnaire about the students characteristics and their academic information. Descriptive and central tendency statistics analysis (mean, standard deviation, frequency and percentage) were done to provide sample information. Then we performed a Mann-Whitney test in the overall sample and in each course and a factorial ANOVA. The results suggest that the university population is heterogeneous and there are significant differences (p <0.05) between the personality styles of students with high and low academic performance, when analyzing the overall sample and in courses of different areas of knowledge. Students of Medicine who have higher performance as personality styles prevalent the conformism and compliance, while students with lower income in this course, the styles are: innovation and discrepancy. Psychology students with higher income are more systematic and lower income students to score significantly on accommodation. The civil engineering students of the two groups differed only in personality style intuition, being such a style more characteristic of higher income students. Students of Management with higher yield stand out more in the style of the doubt and lower yields in these styles: individual, reflection and discrepancy. This study is correlational, but had an exploratory nature because there are no studies about this relationship in Brazil. Therefore, it provided a better understanding of the action characteristics of students with high and low academic performance. Further studies using the Big Five Personality Factors instruments are required because it is the most used model in understanding the influence of personality on students performance. This way, the relation between personality and academic performance will be better discussed. Otherwise, it will be possible to compare with the existing studies in the area
Resumo:
Poverty is a main theme in Brazil: according to official data, poverty reachs 70 million Brazilian people, and, between them, 20 million are unable to provide their basic needs. Psychology, as a welfare profession, and given its historical concerns with social actions, could not be away from this theme. Based on this, we ask: Which answers Psychology can provide, toward both the production of knowledge and the practice about social reality? The purpose of this paper is to investigate the psychological scientific production on poverty and the propositions, limits and impacts of psychological actions. We carried out a three stages documental based study analyzing Brazilian psychological literature: (1) online databases survey (312 papers identified); (2) 109 scientific abstracts accessed and coded; (3) selected 47 scientific papers read and analyzed. Results are presented in three sections: general description of the selected scientific production; characterization of the role of poverty in psychological literature; and themes presented at the papers. The academic production about the main theme (poverty) is dispersed, heterogeneous, and related to other fields of knowledge. Poverty is presented at these studies in many ways, such as: a criterium for sample design and the assessment of its psychological impacts; reports on professional experience with poor population; descriptions of this population group; relationship between poverty and others social themes; developmental and learning problems of poor children. In general, it appears that Psychology has improved the scientific production and experiences with poor population. However, it is necessary to build up theories and technical innovations and also to understand structural boundaries for professional practice with this population group
Resumo:
It is known that the head office world energetics is leaning in the fossil fuels. However, the world panorama is changing quickly, for linked reasons to three of the humanity's great concerns in that century beginning: environment, global economy and energy. The biodiesel production is based on the transesterificação of vegetable oils or animal fats, using catalysts homogeneous or heterogeneous. The process of heterogeneous transesterificação presents lower conversions in comparison with the homogeneous, however, it doesn't present corrosion problems and it reduces to the occurrence of parallel reactions as saponification. In this sense, this work has for purpose the synthesis of a heterogeneous catalyst, KNO3/Al2O3, that soon afterwards was used in the reaction of transesterificação of the oil of the Helianthus annuus L. (sunflower). The solid materials (it supports and catalyst) they were analyzed by diffraction of ray-X (XRD) and electronic microscope of sweeping (MEV). After the analysis of Al2O3, a structure monophase amorphous tetragonal was verified, with characteristic patterns of that material, what could not be visualized in the difratograma of the catalyst. The biodiesel obtained with 4% wt. of KNO3/Al2O3 it was what obtained a better cinematic viscosity 8,3 mm2/s, comparing with the norms of ANP, and it also presented the best conversion tax in ethyl ésteres, in accordance with the quantitative measure starting from TG, that was of 60%. While the biodiesel with 6% wt. and with 8% wt. of KNO3/Al2O3 it was it that no transesterificou, because it was observed in the analysis termogravimétrica of those two materials, a single thermal event, that it corresponds the decomposition or volatilization of the triglycerides