A responsabilidade enunciativa em artigos científicos de pesquisadores iniciantes e contribuições para o ensino da produção textual na graduação

This thesis investigates materialization strategies of non-assumption of enunciation responsibility and inscription of an authorial voice in scientific articles produced by initial researchers in Linguistics. The specific focus lays on identify, describe and interpret: i) linguistics marks that assign enunciation responsibility; ii) the positions taken by the first speaker-enunciator (L1/E1) in relation to points of view (PoV) imputed to second enunciators (e2); and iii) the linguistic marks that assign the formulation of themselves' PoV. As a practical deployment, it is proposed to discuss how to teach taking into account text discursive strategies regarding to enunciation responsibility and also authorship in academic and scientific texts. Our research corpus is formed by eight scientific essays and they were selected in a renamed Linguistics scientific magazine which is high evaluated by Qualis/CAPES (Brazil Science Agency). The methodology follows the assumptions of a qualitative research, and an it has such an interpretative basis, even though it takes support in a quantitative approach, too. Theoretically, we based this research on Textual Analysis of Speech and linguistics theories about linguistic enunciation area. The results show two kinds of movements in PoV management: imputation and responsibility. In imputation contexts, the most recursive linguistic marks were reported speech, indirect speech, reported speech with “that”, modalization in reported speech (in enunciation with “according to”, “in agreement with”, “for”), beyond that we see certain points of non-coincidences of speech, specifically the non-coincidence of the speech itself. The way those linguistic marks occur in the text point out three kinds of enunciation positions that are assumed by L1/E1 in relation to PoV of e2: agreement, disagreement and a pseudo neutrality. It was clearly recursive the imputation followed by agreement (explicit or not), this perspective puts other’s voices to defend a speech assumed like own authorship. In speech responsibility contexts, we observed such a formulation of inner PoV that results from theoretical findings undertaken by novice researchers (revealing how he/she interpreted concepts of the theory) or arising from their research data, allowing them to express with more autonomy and without reporting to speeches from e2. Based on those data, we can say that, in text by initial researchers, the authorship is strongly built upon PoV and also dependent from others' words (theory and the scholars quoted there), taking into account that many contexts in which we can observe agreement position, PoV formulations with words taken from e2 and assumed as own words by syntactic integration, the comments about what the other says, the absence of explanations and additions, as well as a data analysis that could show agreement with the theory used to support the work. These results allow us to visualize how initial researcher dialogs with the theoretical enunciation sources he or she takes as support and how he/she displays the status of a subject doing a research and positioning himself/herself as a researcher/author in the scientific field. In assuming the reported speech, when quoting, as a resource that allows the enunciation responsibility and also when doing evidence to the positions of speaker-enunciator in relation do reported PoV, this suggests to a textual-discursive treatment of quoting in academic and scientific text, in a context of teaching that gives attention to the development of communication skills of initial researcher and that can contribute to insert and interact students in the scientific field.

A responsabilidade enunciativa em artigos científicos de pesquisadores iniciantes e contribuições para o ensino da produção textual na graduação

This thesis investigates materialization strategies of non-assumption of enunciation responsibility and inscription of an authorial voice in scientific articles produced by initial researchers in Linguistics. The specific focus lays on identify, describe and interpret: i) linguistics marks that assign enunciation responsibility; ii) the positions taken by the first speaker-enunciator (L1/E1) in relation to points of view (PoV) imputed to second enunciators (e2); and iii) the linguistic marks that assign the formulation of themselves' PoV. As a practical deployment, it is proposed to discuss how to teach taking into account text discursive strategies regarding to enunciation responsibility and also authorship in academic and scientific texts. Our research corpus is formed by eight scientific essays and they were selected in a renamed Linguistics scientific magazine which is high evaluated by Qualis/CAPES (Brazil Science Agency). The methodology follows the assumptions of a qualitative research, and an it has such an interpretative basis, even though it takes support in a quantitative approach, too. Theoretically, we based this research on Textual Analysis of Speech and linguistics theories about linguistic enunciation area. The results show two kinds of movements in PoV management: imputation and responsibility. In imputation contexts, the most recursive linguistic marks were reported speech, indirect speech, reported speech with “that”, modalization in reported speech (in enunciation with “according to”, “in agreement with”, “for”), beyond that we see certain points of non-coincidences of speech, specifically the non-coincidence of the speech itself. The way those linguistic marks occur in the text point out three kinds of enunciation positions that are assumed by L1/E1 in relation to PoV of e2: agreement, disagreement and a pseudo neutrality. It was clearly recursive the imputation followed by agreement (explicit or not), this perspective puts other’s voices to defend a speech assumed like own authorship. In speech responsibility contexts, we observed such a formulation of inner PoV that results from theoretical findings undertaken by novice researchers (revealing how he/she interpreted concepts of the theory) or arising from their research data, allowing them to express with more autonomy and without reporting to speeches from e2. Based on those data, we can say that, in text by initial researchers, the authorship is strongly built upon PoV and also dependent from others' words (theory and the scholars quoted there), taking into account that many contexts in which we can observe agreement position, PoV formulations with words taken from e2 and assumed as own words by syntactic integration, the comments about what the other says, the absence of explanations and additions, as well as a data analysis that could show agreement with the theory used to support the work. These results allow us to visualize how initial researcher dialogs with the theoretical enunciation sources he or she takes as support and how he/she displays the status of a subject doing a research and positioning himself/herself as a researcher/author in the scientific field. In assuming the reported speech, when quoting, as a resource that allows the enunciation responsibility and also when doing evidence to the positions of speaker-enunciator in relation do reported PoV, this suggests to a textual-discursive treatment of quoting in academic and scientific text, in a context of teaching that gives attention to the development of communication skills of initial researcher and that can contribute to insert and interact students in the scientific field.

Ética na pesquisa em Administração

Ethics on scientific research is approached and often discussed in several areas of knowledge connected to health. In the Administration area there are very few studies which approach the topic of ethics on research. The present paper tried to fill in this gap in the production of knowledge about the topic, investigating how the ethical principles found in the literature and in the codes of conduct are noticed and taken into account in Administration research activities developed by acting researchers in Administration Post Graduation Programs. Theoretically speaking, the study was based mainly on the approaches by Creswell (2007) and Bell and Bryman (2007), which discuss the research ethical principles. Methodologically speaking it was all about an exploratory kind of study, with qualitative research approach. Upon data collection, personal interviews were made aiming at its depth and focus groups were formed. The first stage had interviews with four experienced researchers who took part on a teaching and researching event and on the second stage we used the focus group technique. The focus groups were done in four college institutions along with the post graduation programs in Administration in the states of Rio Grande do Norte, Paraíba and Pernambuco, in Brazil. The results suggest the existence of general principles and parameters for the scientific research recommended in the literature and on official resolution. However, in the Administration area, there are only a few recommendations of good practices when it comes to submitting articles for scientific publications but we found no guidance with ethical principles and parameters which cover all the activities in the scientific research and which specifically meet the research particularities in Administration. The main ethical dilemma pointed by the researchers refers to ethical questions which arise at the time of data collection and on disclosing the results. Most researchers do not know the guidelines and the ethical norms on ethics about research that we have in our country neither do they send in their projects to the research ethics committee. When dilemma arises, they decide the ethical question based on their values and common sense. These elements confirm the thesis that the researcher s procedure in the research activities in Administration is predominantly signed by personal values or by common sense and less by ethical principles, whether by not knowing the normative instruments related to ethics or by disagreeing with any disciplining rules on ethical behavior in the research

O Modelo de gestão participativa do Plano Nacional do Turismo (PNT-2003/2007): a atuação do CONETUR/RN

To implement policies and plans at the tourist sector involve disposition to the establishment of parceries among government and private initiative, space to the action of studious, researchers and professionals of several areas of knowledge and formation, able of to give new courses no only at the tourism, but to the economy how a every, seen which the tourism had a effect multiplicator, reaching 52 sectors of the economy. At this sense, the Brazil came pruning for a new phase of politic actuation at the touristy activity. Until the year 2002, the tourism politic in the Brazil no had detail, because herself treated of isolated actions and many without continuity. However, at to start 2003, several actions were developed in order to contribute for the national touristy planning. The principal was the creation of Ministério do Turismo, accompanied of the formulation and implementation of the Plano Nacional do Turismo (2003/2007). This work pretend to understand the implementation at the Rio Grande do Norte of the model of participative administration extolled by Plano Nacional do Turismo. The your centre detail the action of the Conselho Estadual de Turismo do Rio Grande do Norte (CONETUR), to promote the participation at the tourism public policies. The bibliographical research contemplated diverse sources in order to compile knowledge of credential authors in the quarrel of inherent subjects to the participation and to the tourism public policies, especially at the Brazil. A qualitative perspective the case study was adapted as research method and for attainment of the data interviews with the members of the Conselho had been carried through beyond consultation the referring documents the dynamics of functioning of the Conselho. The principal actuations of the CONETUR, the directives tourism public policies already made and directed to implementation, the type of participation at made decision, the principal difficulties of the implementation of the participative administration model of the Plano Nacional do Turismo and the degree of participation of the members of the Conselho at the reunions had been identified. The results had shown that exist some difficulties at the implementation of the participation at the Conselho Estadual de Turismo do Rio Grande do Norte, knowledge of the Conselheiros of CONETUR function, the presence of bodies which doesn t directly connected at the touristy activity; the absence of time of the Conselheiros to be presents at reunions; the discontinuity of the presidency of the Conselho; among others. So, the CONETUR show himself how a Conselho with participative characteristics, but with some adapted needs.

A satisfação profissional e a cultura organizacional : uma análise a partir do modelo ASH no Centro Federal de Educação Tecnológica do Rio Grande do Norte

With the need of the companies in becoming more competitive within the market, it arises an incessant search for selective human potential, with a high level of capacity and low rotativity, which motivation results in production raise, quality optimization and waste reduction. This scenario requires a strategy development which advantages the Human Resources Quality Management. This way, the model of the Human System Audit (HSA), developed by the Spanish researchers Ouijano and Navarro, presents itself as an important tool to diagnosis and evaluation, contemplating the environment where the organization is inserted, its strategies, its organizational design, its processes and its organizational effectiveness. In this sense, the present study has identified the existent relation between the professional satisfaction and the Organizational Culture, based in the model HSA. The research has been a quantitative-descriptive one and has had as population the technical-administrative workers from the Federal Center of Technical Education of Rio Grande do Norte (CEFET RN). The data collection has occurred during May, 2008, by means of the application of a questionnaire in the HSA model. The sample was composed by 167 subjects, distributed among the Five units of the institution. It was used the factorial analysis, with the extraction method of main components and orthogonal rotation varimax, in order to extract the dimensions of the satisfaction and of the organizational culture and the calculation of Cronbach s Alpha coefficient, to evaluate the reliability of these dimensions. The factorial analysis of the satisfaction indicators has identified four factors,, all of them showing significance: gratefulness and relationship , self-realization , stability and security and physical conditions and social benefits . The result of the factorial analysis with the indicators of the organizational culture has extracted four factors and among them, three of them have obtained significance: Personal Satisfaction Style , Competitive-Denial-Power Style and the Conventional-Dependent Style . After identifying the dimensions of the satisfaction and culture found at CEFET-RN, it has been notice the existence or not of relation among them, through the application of Pearson s coefficient. It has been verified that all of the dimensions of the Professional satisfaction are correlated with some dimension of the organizational culture, having in outstand position, with higher intensity, the relation between the culture style of Personal Satisfaction and the satisfaction factor referring to the self-realization

A satisfação dos clientes internos e o comprometimento organizacional: um estudo à luz do modelo ASH nas indústrias alimentícias no RN

Currently the organizations are passing for continuous cycles of changes due to necessity of survival in the work market. The administration of the future points a way to the organizations of today and tomorrow, the search of the competitiveness from loyalty and motivation of its staff. Of this form, the model of the Auditoria do Sistema Humano (ASH), developed for Spanish researchers and that now it is being applied in Brazil, contemplates a series of dimensions about Human Resources management quality in the companies and the organizational effectiveness, such as the environment where the company is inserted, the strategies, the organizational drawing, the psychological and psychosocial processes, e the reached results. In this direction, the present research analyzed the factors of job satisfaction and organizational commitment, making, also, a relation of causality between the same ones. The quantitative-descriptive research had as population the employees of twenty three nourishing industries of the State of Rio Grande do Norte (Brazil), registered in the Federacy of the Industries of the state. The collection of the data occurred for the months of October of 2005 and March of 2006, by means of the application of questionnaire of model ASH. The sample was composed for 197 employees, however it was observed presence of five outliers, that they had been excluded from the analysis of the data. To extract the dimensions of the satisfaction and the commitment and identification the factorial analysis was used, with extraction method of principal components, rotation Varimax and normalization Kaiser. The gotten dimensions had been evaluated with the calculation of the coefficient Alpha of Cronbach. The factorial analysis of the pointers of the organizational commitment and identification had extracted ten factors. Of these, four had gotten significance of the analyses inside: affective commitment, values commitment, continuance commitment and necessity commitment. The result of the analysis of the pointers of job satisfaction indicated four factors: extrinsic, motivations, relation with the friends and auto-accomplishment. To deal with the data the relation between job satisfaction and organizational commitment it was used technique of multiple regression. The correlation between commitment and satisfaction was satisfactory, detaching the affective commitment with bigger index of correlation, followed of the affective one

O argumento de inclusão enquanto política de acesso à universidade pública

There are a great number of evidences showing that education is extremely important in many economic and social dimensions. In Brazil, education is a right guaranteed by the Federal Constitution; however, in the Brazilian legislation the right to the three stages of basic education: Kindergarten, Elementary and High School is better promoted and supported than the right to education at College level. According to educational census data (INEP, 2009), 78% of all enrolments in College education are in private schools, while the reverse is found in High School: 84% of all matriculations are in public schools, which shows a contradiction in the admission into the universities. The Brazilian scenario presents that public universities receive mostly students who performed better and were prepared in elementary and high school education in private schools, while private universities attend students who received their basic education in public schools, which are characterized as low quality. These facts have led researchers to raise the possible determinants of student performance on standardized tests, such as the Brazilian Vestibular exam, to guide the development of policies aimed at equal access to College education. Seeking inspiration in North American models of affirmative action policies, some Brazilian public universities have suggested rate policies to enable and facilitate the entry of "minorities" (blacks, pardos1, natives, people of low income and public school students) to free College education. At the Federal University of the state Rio Grande do Norte (UFRN), the first incentives for candidates from public schools emerged in 2006, being improved and widespread during the last 7 years. This study aimed to analyse and discuss the Argument of Inclution (AI) - the affirmative action policy that provides additional scoring for students from public schools. From an extensive database, the Ordinary Least Squares (OLS) technique was used as well as a Quantile Regression considering as control the variables of personal, socioeconomic and educational characteristics of the candidates from the Brazilian Vestibular exam 2010 of the Federal University of the state Rio Grande do Norte (UFRN). The results demonstrate the importance of this incentive system, besides the magnitude of other variables

...Em busca da realidade... : a experiência da etnicidade dos Eleotérios (Catu/RN)

The south region of the Rio Grande do Norte has been historically recognized as a place of old indian villages. Inhabitants of the edges of the Catu River, border between the cities of Canguaretama and Goianinha, the Eleotérios in the threshold of 21st century had passed to be seen and self recognized as "remaining indians" of the RN. Their ethnic mobilizations, when becoming public had placed to the intellectual and political fields an old question to be reflected on: the asseverations concerning the "indian disappearing" in the State. This item brings with it other implications. Accessed by a para-oficial indigenism, the Eleotérios had started to establish political relations with the Potiguara indians of the Baía da Traição/PB and the Indian Movement, feeling stimulated to produce and to reproduce forms of social differentiation. In this context, this research is worried about elucidating the process of construction of the ethnicity among the Eleotérios, percepted from the social relations and politics kept with the amplest society, into a particular historical situation involving sugar cane fields owners, proprietaries, militants, researchers, ambiental agencies. The effects of these political and social relations had been extended, making Eleotérios appear to the society as susceptible social actors to the specific policies for the aboriginal populations

Mobilidade urbana sustentável em projetos estruturantes: analise urbanística e ambiental do corredor de transporte da Avenida Bernardo Vieira Natal/RN

The search for a sustainable urban mobility, has recast the public policy of transport and movement for all, in order to contribute to the welfare economic, social and environmental. Within this context, has as its main objective review here in the city of Natal in the state of Rio Grande Norte, the deployment of the new road infrastructure of the transport corridor of Bernardo Vieira Avenue and checking at least with regard to urban areas and environmental chosen here, as will indicators to assess sustainable urban mobility, that the theory has been well constructed, but in practice little way to apply the proposed guidelines for sustainability. To achieve this result, is initially a literature review with the principal investigators of the matter, since the concepts of indicators of sustainable urban mobility. And a second time, participating in to the case study, using the methodology of environmental awareness, through analysis photographs, notes and testimony in the study area ace to reach conclusions

Percepção Ambiental em Museus Paisagens de Arte Contemporânea: a legibilidade dos museus Inhotim/Brasil e em Serralves/Portugal avaliada pelo público/visitante

This thesis nalyzes the wayfinding in Landscape Museum of Contemporary Art (MPAC), based on the Institute of Contemporary Art CACI, Minas Gerais, Brazil and the Museum of Contemporary Art of the Serralves Foundation, Porto, Portugal. The study focuses on the interrelationship of the public/visitors with the landscape, architecture and contemporary art museums in these, in order to understand visual perception and apprehension of such an environment for their users. For both were confronted documentation (visual and written) and people talk. The main hypothesis put forward is that the audience/visitor MPAC appreciates the interrelationship between the natural environment (park/garden) and built environment (the works of contemporary art and the galleries), giving equal value to both. To complement this, a second hypothesis is that during the visit to MPACS, visitors define their paths spontaneously, but strongly influenced by existing visual indicators (maps, signage and striking landscape elements), which facilitate the readability of space, which also contribute to the offered services and the experiences of similar institutions. The analytical basis of the research used the concepts of legibility (LYNCH, 2009), wayfinding (GIBSON, 2009; ARTHUR, PASSINI, 2002; WEISMAN, 1982), Experiential Cotinnum (TUAN, 1985), Space Bound (CRUZ PINTO, 2007) and habitus (BOURDIEU, 1992). Methodologically was used qualitative research (DEMO 2000) by means of a case study (YIN, 2005; STAKE, 1999) and participant observation (WHYTE, 2005). In the two institutions interviews with researchers and curators, behavior observation and questionnaires from employees, trainees, monitors and the public/visitor of the two museums were performed. Although partially referende the initial hypothesis, the research showed that the public/visitor value appears more natural environments, they experience a greater intensity and in addition to the factors listed in the second case, your perception and definition of paths suffer significant influence of emotional relations established with space. Generally the audience/visitor adapts easily to different demands of contemporary art exhibition in the two museums and the built environment (park/garden and museum) interferes with your reading path during the visit, perceived by the public/visitor condition as a factor that favors the enjoyment of works on different mounts (wayfinding), though often become a factor that hinders the legibility of the building and its built environment

Reassentamentos de famílias em projetos de habitação social: avaliação de procedimentos e resultados do projeto Planalto II, Natal /RN

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Atividade antioxidante de fucanas e galactanas extraídas de algas marinhas

Studies made with polysaccharides of seaweed have demonstrated that these present important biological and pharmacological activities. These composites had presented "scavenging" activity of free radicals, which is important in the mediation of the inflammatory process and in the pathology of diverse disease. Recently, this "scavenging" property has taken some researches to evaluate the antioxidant capacity from various polysaccharides. Considering the limited research with polysaccharides and knowing its largely employed by the pharmaceutical and foodstuffs industries, we have objective to verify the actions from fucans and galactans as antioxidants. The fucans are found in brown seaweed and the galactans (carrageenans) in red seaweed. The fucans were obtained from seaweed Padina gymnospora (F0.5 e F1.1 fractions), common to our coastline and one another fucan, fucoidan, was of origin commercial and extracted from seaweed Fucus vesiculosus. The λ, κ e ι carrageenans were also of origin commercial. The antioxidant activities were tested in superoxide and hydroxyl systems to generated free radicals and for the inhibition of the lipid peroxidation. The results obtained to inhibition of formation the superoxide radicals demonstrated that all polysaccharides presented scavenging activity of superoxide radicals. The fucoidan, F0.5 and F1.1 fractions presented IC50 of 0.058; 0.243 and 0.243 mg/mL, respectively, while IC50 of the λ, κ and ι carrageenans were 0.046; 0.112 and 0.332 mg/mL, respectively. The results to inhibition of formation the hydroxyl radicals demonstrated that all sample had low effect in the inhibition of the formation of these radicals, except the F0.5. For these radicals the IC50 were 0.157 and 0.353 mg/mL to the fucoidan and F1.1, respectively and 0.357; 0.335 and 0.281 mg/mL to λ, κ and ι carrageenans, respectively. All the samples were capacity to inhibition the peroxidation, it present the IC50 of 1.250; 2.753 and 2.341 mg/mL to fucoidan, F0.5 and F1.1, respectively. Already the λ, κ and ι carrageenans presented the IC50 of 2.697; 0.323 and 0.830 mg/mL, respectively. With these findings, we conclude that polysaccharides used in this study presented activity antioxidant, and that fucoidan and the λ carrageenan show a significant "scavenging" activity for the radicals superoxide and the κ carrageenan a significant inhibitory activity for the lipid peroxidation

Da bancada ao Bureau: análise do desenvolvimento da biotecnologia no Nordeste Brasileiro sob o enfoque de Sistema Regional de Inovação

The starting point of the present work consisted of investigating the development of biotechnology in the Northeast region of Brazil from the perspective of a Regional Innovation System (RIS). The theoretical framework adopted relied on the approaches and concepts presented by the Neo-Schumpeterian perspective. This framework was chosen because, by means of the Innovation System concept, this literature allows us to analyze the relationships and configurations of actors, as well as the role of the state and of social, science and technology, and economic policies in the studied region. The analysis considered four selected dimensions: physical infrastructure, human capital, scientific production, and funding. These variables were chosen because they allow us to verify the possibilities and limitations of developing a biotechnology RIS in the Northeast of Brazil, and these elements would help in answering the question behind this dissertation. The location of the physical infrastructure was determined by means of bibliographic and documental research and interviews with heads of institutions that do biotechnology research. Regarding human capital, the analysis focused on resource training in biotechnology, highlighting graduate courses and research groups in the area. To measure knowledge production, we delimited scientific collaboration among researchers in the field of biotechnology as the focus of this category. For the funding dimension, information was gathered from reports available at the websites of national and state funding agencies. The data was analyzed through method triangulation, involving quantitative and qualitative research stages. To back the analyses, we revisited the integration policies in the area of Science, Technology and Innovation. Our analysis has shown that these policies play a crucial role in the development of biotechnology in the region being studied. The data revealed that the physical infrastructure is concentrated in only three states (Bahia, Ceará, and Pernambuco). In this regard, the Northeast Biotechnology Network (Renorbio) stands out as a strategic actor, enabling states with poor infrastructure to develop research through partnerships with institutions located in another state. We have also verified that the practices involving human resource training and knowledge production are factors that enable the emergence of a regional system for biotechnology in the studied region. As limitations, we have verified the low immersion level of regional actors, the heterogeneity of socioeconomic indicators, the lack of financial resources, and a low innovation culture in the business sector. Overall, we have concluded that the development of a Regional Innovation System in Biotechnology, based on the current regional dynamics, depends on an effective change in the behavior of the social agents involved, both in the national and regional dimensions as well as in the public and private spheres

Estruturas cerâmicas a base de zircônia e alumina utilizadas na confecção de infra - estruturas para coroas e pontes fixas

The continuous advances in ceramic systems for crowns and bridges infrastructure getting researchers and manufacturers looking for a material that has good mechanical properties and aesthetic. The purpose of this study was to verify in which composition and sintering temperature the ceramic system for infrastructure composed of alumina and zirconia would have the best mechanical properties. With this objective we made in UFRN laboratories 45 test bodies in the form of rectangular bars with the following dimensions: 30mm x 8mm x 3mm, where we separated by the sintering temperature: 1200°C, 1300ºC and 1400ºC, and by comp osition: 33% Zirconia + 67% Alumina; 50% Zirconia + 50% Alumina and 25% Zirconia + 75% Alumina, these test bodies were not infiltrated with glass. Also, were made nine test bodies by a technical from a laboratory with a commercial ceramic system: in the Ceram Zircônia (Vita - Zahnfabrik) with the following dimensions: 20mm x 10mm x 0.5mm, these test bodies following all recommendations of the manufacturer and were infiltrated with glass. Were realized optical and electronic microscopy analyses, hardness testing, resistance to bending in three points, porosity and bulk density. After analysis of the results we verified that with the increasing of sintering temperature, increased the value of resistance to bending, but with the same temperature there was no significant difference between the different compositions, samples made with the commercial ceramic that were infiltrated, presented a resistance to bending six times greater than the samples sintered to 1400°C and which have not been infiltra ted. There was no significant difference between the values of apparent porosity for the samples made in UFRN laboratories, but the samples of commercial ceramic obtained 0% in porosity apparent value. In tests of Rockwell Hardness there is an increase in the value of Hardness, with the increase of sintering temperature for the samples not infiltrated. Samples infiltrated showed similar values as the samples sintered in 1400°C. There was no significant difference between the values of apparent density among samples manufactured in UFRN laboratories and samples made with a commercial ceramic

Síntese e caracterização de catalisadores nanométricos de LaSrNiO4 para aplicação em dessulfurização de tiofeno

The mixed metal oxides constitute an important class of catalytic materials widely investigated in different fields of applications. Studies of rare earth nickelates have been carried by several researchers in order to investigate the structural stability afforded by oxide formed and the existence of catalytic properties at room temperature. So, this study aims synthesize the nanosized catalyst of nickelate of lanthanum doped with strontium (La(1-x)SrxNiO4-d; x = 0,2 and 0,3), through the Pechini method and your characterization for subsequent application in the desulfurization of thiophene reaction. The precursor solutions were calcined at 300ºC/2h for pyrolysis of polyester and later calcinations occurred at temperatures of 500 - 1000°C. The resulting powders were characterized by thermogravimetric analysis (TG / DTG), surface area for adsorption of N2 by BET method, X-ray diffraction (XRD), scanning electron microscopy (HR_SEM) and spectrometry dispersive energy (EDS). The results of XRD had show that the perovskites obtained consist of two phases (LSN and NiO) and from 700ºC have crystalline structure. The results of SEM evidenced the obtainment of nanometric powders. The results of BET show that the powders have surface area within the range used in catalysis (5-50m2/g). The characterization of active sites was performed by reaction of desulfurization of thiophene at room temperature and 200ºC, the relation F/W equal to 0,7 mol h-1mcat -1. The products of the reaction were separated by gas chromatography and identified by the selective detection PFPD sulfur. All samples had presented conversion above 95%