Síntese e caracterização do carbeto de molibdênio nanoestruturado para fins catalíticos na reação de oxidação parcial do metano

The nanostructures materials are characterized to have particle size smaller than 100 nm and could reach 1 nm. Due to the extremely reduced dimensions of the grains, the properties of these materials are significantly modified relatively when compared with the conventional materials. In the present work was accomplished a study and characterization of the molybdenum carbide, seeking obtain it with particles size in the nanometers order and evaluate its potential as catalyst in the reaction of partial methane oxidation. The method used for obtaining the molybdenum carbide was starting from the precursor ammonium heptamolybdate of that was developed in split into two oven, in reactor of fixed bed, with at a heating rate of 5ºC/min, in a flow of methane and hydrogen whose flow was of 15L/h with 5% of methane for all of the samples. The studied temperatures were 350, 500, 600, 650, 660, 675 and 700ºC and were conducted for 0, 60, 120 and 180 minutes, and the percent amount and the crystallite size of the intermediate phases were determined by the Rietveld refinement method. The carbide obtained at 660ºC for 3 hours of reaction showed the best results, 24 nm. Certain the best synthesis condition, a passivating study was accomplished, in these conditions, to verify the stability of the carbide when exposed to the air. The molybdenum carbide was characterized by SEM, TEM, elemental analysis, ICP-AES, TG in atmosphere of hydrogen and TPR. Through the elemental analysis and ICP-AES the presence carbon load was verified. TG in atmosphere of hydrogen proved that is necessary the passivating of the molybdenum carbide, because occur oxidation in room temperature. The catalytic test was accomplished in the plant of Fischer-Tropsch of CTGAS, that is composed of a reactor of fixed bed. Already the catalytic test showed that the carbide presents activity for partial oxidation, but the operational conditions should be adjusted to improve the conversion

Caracterização de água produzida na indústria de petróleo para fins de descarte e otimização do processo de separação óleo/água

The oil industry has several segments that can impact the environment. Among these, produced water which has been highlight in the environmental problem because of the great volume generated and its toxic composition. Those waters are the major source of waste in the oil industry. The composition of the produced water is strongly dependent on the production field. A good example is the wastewater produced on a Petrobras operating unit of Rio Grande do Norte and Ceará (UO-RNCE). A single effluent treatment station (ETS) of this unit receives effluent from 48 wells (onshore and offshore), which leads a large fluctuations in the water quality that can become a complicating factor for future treatment processes. The present work aims to realize a diagnosis of a sample of produced water from the OU - RNCE in compliance to certain physical and physico-chemical parameters (chloride concentration, conductivity, dissolved oxygen, pH, TOG (oil & grease), nitrate concentration, turbidity, salinity and temperature). The analysis of the effluent is accomplished by means of a MP TROLL 9500 Multiparameter probe, a TOG/TPH Infracal from Wilks Enterprise Corp. - Model HATR - T (TOG) and a MD-31 condutivimeter of Digimed. Results were analyzed by univariated and multivariated analysis (principal component analysis) associated statistical control charts. The multivariate analysis showed a negative correlation between dissolved oxygen and turbidity (-0.55) and positive correlations between salinity and chloride (1), conductivity, chloride and salinity (0.70). Multivariated analysis showed there are seven principal components which can explain the variability of the parameters. The variables, salinity, conductivity and chloride were the most important variables, with, higher sampling variance. Statistical control charts have helped to establish a general trend between the physical and chemical evaluated parameters

Síntese e caracterização de tungstatos de cério e estrôncio para fins catalíticos

The main goal of this work was to produce nanosized ceramic materials of the family of the tungstates (tungstates of cerium and strontium), and test them for their catalytic activity in processes involving the transformation of methane (CH4). The methodology used for the synthesis of the ceramic powders involved the complexation combining EDTA-citrate. The materials characterization was performed using simple and differential thermogravimetry, x-ray diffraction, transmission electron microscopy, and energy dispersive spectroscopy (EDS). The microstructure analysis was performed using the refinement by the Rietveld method, and the crystallite size and distribution of the materials was elucidate by the Scherrer and Williamson-Hall methods. The conditions of the synthesis process for the three envisaged materials (SrWO4, SrWO4 using tungsten oxide concentrate as raw material, and Ce2(WO4)3) were adjusted to obtain a single phase crystalline material. The catalytic tests were carried out in the presence of methane and synthetic air, which is composed of 21% O2 and 79% N2. The analysis of the conversion of the reaction was done with the aid of an fourier transform infrared device (FTIR). The analysis showed that, structurally, the SrWO4 produced using raw materials of high and poor purity (99% and 92%, respectively) are similar. The ideal parameters of calcination, in the tested range, are temperature of 1000 °C and time of calcination 5 hours. For the Ce2(WO4)3, the ideal calcination time and are temperature 15 hours and 1000°C, respectively. The Williamson-Hall method provided two different distributions for the crystallite size of each material, whose values ranged between the nanometer and micrometer scales. According to method of Scherrer, all materials produced were composed of nanometric crystallites. The analyses of transmission electron microscopy confirmed the results obtained from the Williamson- Hall method for the crystallite size. The EDS showed an atomic composition for the metals in the SrWO4 that was different of the theoretical composition. With respect to the catalytic tests, all materials were found to be catalytically active, but the reaction process should be further studied and optimized.

Estudo da funcionalidade de espécies comestíveis do semiárido nordestino e estratégias para sua utilização como ingredientes para fins alimentícios

The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

Para uma crítica da razão socioeducativa em entidades assistenciais

Buscou-se cartografar as instituições de assistência social que atendem à infância e à adolescência consideradas em situação de risco pessoal e social, em um município do interior do estado de São Paulo, utilizando o instrumental da análise institucional. O papel de membro do Conselho Municipal dos Direitos da Criança e do Adolescente e do Conselho Municipal de Assistência Social facultou a realização de uma análise documental nos arquivos desses Conselhos, relativa às entidades assistenciais cadastradas, tais como organizações governamentais, organizações não-governamentais e outros estabelecimentos filantrópicos. Os resultados indicam que, no universo da Assistência Social, a constelação criança/adolescente orbita em torno do astro-rei socioeducativo. Todas as atividades desenvolvidas nas entidades parecem recobertas por esse significantemestre, que conota dimensões pedagógicas e terapêuticas, educativas e corretivas, de vigilância e de prevenção, promovendo controle e normalização.

Análise de necessidades de inglês para fins específicos em um curso de graduação em turismo

This study presents the results of a survey conducted in the area of English for Specific Purposes (ESP) in order to identify (1) the learning needs of students in a course in Tourism, their desires and lacks, at a federal university, with respect to use of English; (2) the needs of the present situation of teachers and the coordinator of that course as to the language; (3) the needs of the target situation of professionals (graduates) and companies with respect to this language. This research is a case study (STAKE, 1998; YIN, 2009) and was used for data collection, instruments such as questionnaires, semi-structured interviews, and document on the Tourism Course. To this end, it was adopted the theoretical basis for the constructs of English for Specific Purposes (ESP) Inglês para Fins Específicos (IFE) in Brazil, also known as Inglês Instrumental, whose foundation is based on the work by Hutchinson and Waters (1987), Robinson (1991), Dudley-Evans and St. John (1998), Celani, Deyes, Holmes, Scott (2006), among others, since this work is devoted to a specific area, Tourism. Results show that students opined the ability to prioritize reading and speaking into the classroom. Professionals reported that the latter is an indispensable tool for entering the labor market, yet they feel unprepared and need to attend English language courses in private language schools. The testimony of company executives also point to this deficiency. Finally, the present situation of teachers reveals that, while advocating the use of English in the classroom, this is not because students prefer their mother tongue. There is also an evident lack of needs analysis. Eventually, the coordinator said that there is some uncertainty as to the methodology, content and language skills worked, and the lack of interaction among teachers of English. It was concluded, therefore, it is important to conduct a needs analysis so that one can redesign a course that meets the different contextual needs: students, teachers, coordination, represented by the institutional needs, and the labor market

Histórias de professores universitários sobre ensinar inglês para fins específicos

This research has as its theoretical and methodological assumptions (1) the Narrative Inquiry (CLANDININ; CONNELLY, 2011), (2) the Systemic Functional Grammar (HALLIDAY, 1985, 1994; THOMPSON, 2002; EGGINS, 1994; HALLIDAY; MATTHIESSEN, 2004) and (3) the English for Specific Purposes Approach (ESP - HUTCHINSON; WATERS, 1987; CELANI, 2005; RAMOS, 2005), and its overall objective is to survey the meanings construed by the participants who are ESP practitioners and have not received a specific education to teach this approach at their undergraduation. The field texts and therefore the analises were divided into two distinct groups: the first with data generated from a questionnaire applied to nine professors from a federal university in the northeast of Brazil, which contains open and closed questions about their training and their experiences in teaching ESP; the second group, focusing this time on the experiences of three professors from the first group who were still teaching ESP, with data generated from interviews with these participants in addition to the data generated from their autobiographies and from the researcher´s as well. The computational tool WordSmith Tools 6.0 (SCOTT, 2012) was used to select, organize, and quantify data to be analyzed in the first group of texts, identifying the types of Processes and Participants through the Transitivity System (HALLIDAY; MATTHIESSEN, 2004). The Processes which were more used by the professors in the questionnaire were the Material, followed by the Relational and then the Mental ones, indicating that most professors reported their actions related to the teaching of ESP, rated or evaluated the approach, their training to teach it and their experiences, hence, rarely showing their thoughts and emotions about teaching ESP. Most of the nine professors say they carry out needs analysis, but not all do it according to the authors cited by them or the ones that are considered a reference in this area, such as the ones used in this research as reference. Similarly, their definitions and conceptions of ESP, in most cases, differed from these authors. All the professors claim not having had specific education to teach ESP at the undergraduation. When examining the stories of the four teachers, in the second group of the field texts, based on meaning composition according to Ely, Vinz, Downing and Anzul (2001), it was revealed that the kind of knowledge they report using when they teach ESP is related to their Personal Practical Knowledge and their Professional Knowledge (ELBAZ, 1983; CLANDININ, 1988). In their autobiographies, metaphors were also identified and they represent their concepts of teaching and being a teacher. Through this research, we hope to contribute to the understanding of what teaching ESP might mean for professors in the researched context and also to the continuing education of ESP practitioners, as well as to a review of the curricula in the English language undergraduate courses and of the role of ESP in the training of these professionals

Caminhos para a universalização dos serviços de água e esgotos no Brasil: a atuação das entidades reguladoras para indução da eficiência dos prestadores de serviços

The deficit of water and sewerage services is a historic problem in Brazil. The introduction of a new regulatory framework, in 2007, presented ways intending to overcome these deficits, among them, the providers efficiency improvement. This thesis aims to analyze the regulators performance regarding its ability to induce the efficiency of the Brazilian water and sewerage services providers. To this end, an analytical approach based on a sequential explanatory strategy was used, and it consists of three steps. In the first step, the Data Envelopment Analysis ( DEA ) was used to measure the providers efficiency in 2006 and 2011. The results show that the average efficiency may be considered high; however significant inefficiencies among the 29 analyzed providers were detected. The ones in the Southeast region showed better performance level and Northeast had the lowest. The local and the private providers were more efficient on average. In 2006 and 2011 the average performance was higher among non-regulated providers. In 2006 the group regulated by local agencies had the best average performance, in 2011, the best performance was the group regulated by the consortium agencies. To analyse the second step was used the Malmquist Index, it pointed that the productivity between 2006 and 2011 dropped. The analysis through decomposing Malmquist Index showed a shift of technical efficiency frontier to a lower level, however was detected a small provider s advance towards the frontier. Only the Midwest region recorded progress in overall productivity. The deterioration in the total factor productivity was higher among regional providers but the local ones and the private agencies moved quickly to the frontier level. The providers regulated from 2007 showed less decrease on the total productivity and the results of the catch up effect were more meaningful. In the last step, the regulators standardization activity analyses noted that there are agencies that had not issued rules until 2011. The most standards topics discussed in the issued rules were the tariff adjustments and the setting of general conditions for the provision and use of services; in another hand, the least covered topics were new technologies incentive and the introduction of efficiency-inducing regulatory mechanisms and productivity gains for price reviews. Regulators created from 2007 were more active proportionately. Even with the advent of the regulatory framework and the creation of new regulatory bodies, the evidence points to a reality in which the actions of these agencies have not been ensuring that providers of water and sewage, regulated by them, has achieved better performance. The non- achievement of regulatory goals can be explained by the incipient level of performance of the Brazilian regulatory authorities, which should be strengthened because of its potential contribution to the Brazilian basic sanitation department

Dermolipoma e prolapso de gordura orbital: duas entidades distintas

Objetivo: Relatar 20 pacientes portadores de dermolipoma e 10 pacientes com prolapso de gordura orbitária, ressaltando aspectos que podem auxiliar para o diferencial clínico destas duas entidades. Métodos: Foi realizado estudo retrospectivo de 12 anos, avaliando-se portadores de dermolipoma e de prolapso de gordura orbitária, atendidos na Faculdade de Medicina de Botucatu-SP. Resultados: No período foram detectados 20 (1,6 pacientes/ano) portadores de dermolipoma e 10 (0,8 pacientes/ano), de prolapso de gordura orbitária. Quanto ao sexo, o dermolipoma acometeu mais mulheres e o prolapso de gordura orbital ocorreu mais em homens. Nos portadores de dermolipoma, a lesão foi encontrada no canto externo em todos os pacientes, sendo bilateral em apenas um caso; nos com prolapso de gordura orbital, a lesão localizava-se no canto externo em 9 dos 10 portadores. Sete pacientes com dermolipoma possuíam associação com outras doenças oculares e em dez pacientes a lesão estava presente desde o nascimento. Conclusão: O dermolipoma é semelhante ao prolapso de gordura orbitária quanto à localização e aparência clínica. Porém, o dermolipoma está presente desde o nascimento, ocorre mais no sexo feminino, podendo estar associado a outras doenças oculares. O prolapso de gordura orbitária é alteração que ocorre em indivíduos idosos, geralmente do sexo masculino.

Non-destructive genetic sampling in fish. An improved method for DNA extraction from fish fins and scales

DNA-based studies have been one of the major interests in conservation biology of endangered species and in population genetics. As species and population genetic assessment requires a source of biological material, the sampling strategy can be overcome by non-destructive procedures for DNA isolation. An improved method for obtaining DNA from fish fins and scales with the use of an extraction buffer containing urea and further DNA purification with phenol-chloroform is described. The methodology combines the benefits of a non-destructive DNA sampling and its high efficiency. In addition, comparisons with other methodologies for isolating DNA from fish demonstrated that the present procedure also becomes a very attractive alternative to obtain large amounts of high-quality DNA for use in different molecular analyses. The DNA samples, isolated from different fish species, have been successfully used on random amplified polymorphic DNA (RAPD) experiments, as well as on amplification of specific ribosomal and mitochondrial DNA sequences. The present DNA extraction procedure represents an alternative for population approaches and genetic studies on rare or endangered taxa.

Sete motivações teóricas para o uso da modelagem baseada no indivíduo em ecologia

A modelagem baseada no indivíduo tem sido crescentemente empregada para analisar processos ecológicos, desenvolver e avaliar teorias, bem como para fins de manejo da vida silvestre e conservação. Os modelos baseados no indivíduo (MBI) são bastante flexíveis, permitem o uso detalhado de parâmetros com maior significado biológico, sendo portanto mais realistas do que modelos populacionais clássicos, mais presos dentro de um rígido formalismo matemático. O presente artigo apresenta e discute sete razões para a adoção dos MBI em estudos de simulação na Ecologia: (1) a inerente complexidade de sistemas ecológicos, impassíveis de uma análise matemática formal; (2) processos populacionais são fenômenos emergentes, resultando das interações entre seus elementos constituintes (indivíduos) e destes com o meio; (3) poder de predição; (4) a adoção definitiva, por parte da Ecologia, de uma visão evolutiva; (5) indivíduos são entidades discretas; (6) interações são localizadas no espaço e (7) indivíduos diferem entre si.

Influência da secagem, armazenamento e embalagem nos resultados da análise química de terra para fins de fertilidade

Amostras de terra provenientes de uma Terra Roxa Estruturada e um Latossol Vermelho Escuro textura média foram analisados quimicamente para se verificar a influência de embalagem (caixa de papelão saco de polietileno), tempo de armazenamento (1-32 dias) e processo de secagem (ao ar ou estufa a 60°C). A secagem foi o fator que mais influenciou a análise determinando variações nos resultados analíticos principalmente para pH e fósforo. O armazenamento apresentou influência apenas para fósforo trocável enquanto que a embalagem não influiu nos resultados. As variações dos resultados analíticos para pH, em função da secagem, e fósforo, em função da secagem e tempo de armazenamento, foram de ordem a alterar a interpretação da fertilidade quanto aos limites de classes.

Técnicas de utilização de dicionário como material didático na aula de LE para fins específicos

Este artigo apresenta uma metodologia de trabalho relacionado ao uso do dicionário como material didático na aula de língua estrangeira com fins específicos, em atividades como desenvolvimento de vocabulário, gramática, pronúncia, uso de língua, cultura, leitura e interpretação de texto. Com certas técnicas, os professores podem aproveitar esse material em suas aulas e orientar seus alunos sobre qual dicionário adquirir e como empregá-lo de maneira eficiente. Oferecemos algumas sugestões de atividades para serem realizadas com o dicionário, seja em aulas para alunos particulares ou em cursos profissionalizantes em áreas específicas.

El papel de las entidades multilaterales regionales en el desarrollo sostenible

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Entidades de gestión del agua a nivel de cuencas: experiencia de Argentina

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