998 resultados para resíduo urbano


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Recognizing the importance the workplace has on mental health of the individual, the objective of this study was to investigate the relationship between the burnout syndrome and the sources of physical and emotional wear which permeate the work conditions of the urban public transport system of the city of Natal. Although existent in international literature, research on burnout in the professional transport category and studies directed to this category are not a tradition in Brazil. The research was carried out using 412 drivers and money-changers of two transport companies of Natal. To collect the data, two questionnaires and a semi-structured interview were used. The first instrument, developed and validated during the research, investigated the sources of wear and the second, the syndrome of burnout. As its main results, two sources of empirical wear were identified as follows: (1) the Conflict of Values and the Lack of Justice at the Workplace, (2) Union and Reward. Besides these, it was observed that there is an incidence of the syndrome of burnout among the drivers and money-changers of urban transport by bus, not only in the caring occupations studied before in Natal and Brazil and that this incidence is related to the sources of wear which permeate the work conditions of these professionals

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In present work, mesoporous materials of the M41S family were synthesized, which were discovered in the early 90s by researchers from Mobil Oil Corporation, thus allowing new perspectives in the field of catalysis. One of the most important members of this family is the MCM-41, which has a hexagonal array of mesopores with pore diameters ranging from 2 to 10 nm and a high surface area, enabling it to become very promising for the use as a catalyst in the refining of oil in the catalytic cracking process, since the mesopores facilitate the access of large hydrocarbon molecules, thereby increasing the production of light products, that are in high demand in the market. The addition of aluminum in the structure of MCM-41 increases the acidity of the material, making it more beneficial for application in the petrochemical industry. The mesoporous materials MCM-41 and Al-MCM-41 (ratio Si / Al = 50) were synthesized through the hydrothermal method, starting with silica gel, NaOH and distilled water. CTMABr was used as template, for structural guiding. In Al-MCM-41 the same reactants were used, with the adding of pseudoboehmite (as a source of aluminum) in the synthesis gel. The syntheses were carried out over a period of four days with a daily adjustment of pH. The optimum conditions of calcination for the removal of the organic template (CTMABr) were discovered through TG / DTG and also through analysis by XRD, FTIR and Nitrogen Adsorption. It was found that both the method of hydrothermal synthesis and calcination conditions of the studies based on TG were promising for the production of mesoporous materials with a high degree of hexagonal array. The acidic properties of the materials were determined by desorption of n-butylamine via thermogravimetry. One proved that the addition of aluminum in the structure of MCM-41 promoted an increase in the acidity of the catalyst. To check the catalytic activity of these materials, a sample of Atmospheric Residue (RAT) that is derived from atmospheric distillation of oil from the Pole of Guamaré- RN was used. This sample was previously characterized by various techniques such as Thermogravimetry, FTIR and XRF, where through thermal analysis of a comparative study between the thermal degradation of the RAT, the RAT pyrolysis + MCM-41 and RAT + Al- MCM-41. It was found that the Al-MCM-41 was most satisfactory in the promotion of a catalytic effect on the pyrolysis of the RAT, as the cracking of heavy products in the waste occurred at temperatures lower than those observed for the pyrolysis with MCM-41, and thereby also decreasing the energy of activation for the process and increasing the rates of conversion of residue into lighter products

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O objetivo deste trabalho foi verificar, no sistema integração agricultura-pecuária, a possibilidade de utilizar uma cultura para pastejo cujos resíduos permitam produção de palha suficiente para a manutenção do plantio direto, bem como avaliar a produção da forrageira e do resíduo em diferentes distâncias em relação ao centro do pivô, em três épocas, e o desempenho econômico do sistema. Avaliaram-se o impacto do pastejo rotacionado de sorgo forrageiro em plantio direto, sob irrigação em um pivô central de 75 ha, sobre a produção de matéria seca do sorgo forrageiro, a quantidade de resíduos, o custo de produção e o ganho de peso animal. O ensaio foi conduzido num Latossolo Vermelho Distrófico. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas, com quatro tratamentos principais: locais de amostragem em diferentes distâncias em relação ao centro do pivô; três tratamentos secundários (ciclos de pastejos) e sete repetições (sete piquetes de 9,37 ha para pastejo, dispostos na forma de pizza). Os resultados permitiram concluir que: a produção do sorgo forrageiro foi suficiente para permitir um ganho 621 kg ha-1 de peso vivo e a quantidade de resíduos de sorgo após o pastejo foi suficiente para suprir o aporte anual de matéria seca de palha necessária para a manutenção do plantio direto; a área, após os pastejos, continuou passível de ser explorada no sistema de plantio direto, e o sistema pesquisado mostrou-se técnica e economicamente viável.

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Biodiesel production has increased over the last decade because of the benefits associated with this fuel, including renewability, domestic feedstock, lower toxicity, and biodegradability. From 2008, the use of beef tallow as a feedstock for biodiesel production in Brazil has increased in significance, representing the second largest source of biodiesel, after soybeans. However, the performance of biodiesel in cold weather conditions is worse than diesel because of deposition of insoluble at low temperatures, accelerating the plugging of fuel filters and injectors of the vehicle engine. Studies have been conducted on beef tallow biodiesel, mostly related to the properties of thermal and oxidative stability. However, few studies have described the nature of the precipitate formed and its influence on product quality. Research suggests that the cause of deposition is related to the nature of saturated esters and monoacylglycerols as inducing agents. This study monitored the levels of mono-, diand triacylglycerols, the oxidation stability and the cold filter plugging point (CFPP) in beef tallow biodiesel samples from two commercial producers in Brazil for a period of twelve months. Filtered precipitates were analyzed by comparative techniques of GCFID, HPLC-UV/VIS, HPLC-MS-IT-TOF and TG to verify the nature, using monopalmitin and monostearin as reference standards. The formation of precipitate reduced the levels of monoacylglycerols in the beef tallow biodiesel. GC-FID and LCMS- IT-TOF results confirmed the nature of the deposit as saturated monoacylglycerols, predominantly monostearin and monopalmitin as the second major component. Moreover the TG analysis of the residue indicated similar thermal decomposition of the reference standards. The precipitate did not affect the oxidation stability of beef tallow biodiesel and the CFPP characteristic of blends up B60. However, the presence of iron reduced significantly the oxidation stability of biodiesel

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Biodiesel production has increased over the last decade because of the benefits associated with this fuel, including renewability, domestic feedstock, lower toxicity, and biodegradability. From 2008, the use of beef tallow as a feedstock for biodiesel production in Brazil has increased in significance, representing the second largest source of biodiesel, after soybeans. However, the performance of biodiesel in cold weather conditions is worse than diesel because of deposition of insoluble at low temperatures, accelerating the plugging of fuel filters and injectors of the vehicle engine. Studies have been conducted on beef tallow biodiesel, mostly related to the properties of thermal and oxidative stability. However, few studies have described the nature of the precipitate formed and its influence on product quality. Research suggests that the cause of deposition is related to the nature of saturated esters and monoacylglycerols as inducing agents. This study monitored the levels of mono-, diand triacylglycerols, the oxidation stability and the cold filter plugging point (CFPP) in beef tallow biodiesel samples from two commercial producers in Brazil for a period of twelve months. Filtered precipitates were analyzed by comparative techniques of GCFID, HPLC-UV/VIS, HPLC-MS-IT-TOF and TG to verify the nature, using monopalmitin and monostearin as reference standards. The formation of precipitate reduced the levels of monoacylglycerols in the beef tallow biodiesel. GC-FID and LCMS- IT-TOF results confirmed the nature of the deposit as saturated monoacylglycerols, predominantly monostearin and monopalmitin as the second major component. Moreover the TG analysis of the residue indicated similar thermal decomposition of the reference standards. The precipitate did not affect the oxidation stability of beef tallow biodiesel and the CFPP characteristic of blends up B60. However, the presence of iron reduced significantly the oxidation stability of biodiesel

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A grande expansão das indústrias e do mercado consumidor tem provocado, nas últimas décadas, a geração de elevadas quantidades de resíduos, os quais têm constituído constante preocupação econômica e ambiental. Objetivou-se, neste trabalho, analisar a viabilidade econômica do uso de três doses de composto orgânico, oriundo da compostagem de resíduos da extração da celulose, em substituição à adubação mineral, na cultura do eucalipto, no município de Selvíria, MS. A metodologia de custos adotada foi a do custo operacional total e do custo total. Concluiu-se que, por causa do elevado custo de transporte e aplicação, a adubação orgânica mostrou-se mais onerosa em relação à mineral, sendo sua utilização viável, economicamente, apenas nas proximidades da indústria produtora.

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In this work were synthesized and characterized the materials mesoporous SBA-15 and Al- SBA-15, Si / Al = 25, 50 and 75, discovered by researchers at the University of California- Santa Barbara, USA, with pore diameters ranging from 2 to 30 nm and wall thickness from 3.1 to 6.4 nm, making these promising materials in the field of catalysis, particularly for petroleum refining (catalytic cracking), as their mesopores facilitate access of the molecules constituting the oil to active sites, thereby increasing the production of hydrocarbons in the range of light and medium. To verify that the materials used as catalysts were successfully synthesized, they were characterized using techniques of X-ray diffraction (XRD), absorption spectroscopy in the infrared Fourier transform (FT-IR) and adsorption nitrogen (BET). Aiming to check the catalytic activity thereof, a sample of atmospheric residue oil (ATR) from the pole Guamaré-RN was performed the process by means of thermogravimetry and thermal degradation of catalytic residue. Upon the curves, it was observed a reduction in the onset temperature of the decomposition process of catalytic ATR. For the kinetic model proposed by Flynn-Wall yielded some parameters to determine the apparent activation energy of decomposition, being shown the efficiency of mesoporous materials, since there was a decrease in the activation energy for the reactions using catalysts. The ATR was also subjected to pyrolysis process using a pyrolyzer with gas chromatography coupled to a mass spectrometer. Through the chromatograms obtained, there was an increase in the yield of the compounds in the range of gasoline and diesel from the catalytic pyrolysis, with emphasis on Al-SBA-15 (Si / Al = 25), which showed a percentage higher than the other catalysts. These results are due to the fact that the synthesized materials exhibit specific properties for application in the process of pyrolysis of complex molecules and high molecular weight as constituents of the ATR

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It discusses the social place occupied by the youth of outlying areas in the urban social imaginary. Having the stigma issue as an axle, it presents the essential categories to its understanding, such as (in)visibility, violence and exclusion, pointing out this quarrel in a social- anthropologychal approach. The research was carried through with teenagers of the age band from 15 to 24 years old, living in Mãe Luiza neighborhood, a popular quarter of Natal s east zone, that has close to 16.000 inhabitants. Quantitative methods had been used, through questionnaires application to 364 teenagers; and qualitative methods through the accomplishment of 5 focal groups with the adolescents. The results point a strong youth concern regarding the quarter daily violence; and the weaved image in the urban social imaginary of the neighborhood As dangerous", "violent". It is also possible to perceive the social groups diversity, in general, related with churches and cultural activities, which are important catalysers of the envolvement process of the youth with the quarter

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This paper analyzes the influence of trade and services in the reconfiguration of urban space in Natal, with the Avenues Bernardo Vieira end Roberto Freire Engineer as privileged analysis. Initially, we discussed the concepts of production and reproduction of urban space, urban centralities, decentralized, services and public policies, especially transport and tourism. Then, we show the construction of urban space from Natal, highlighting the historical formation of the districts of Ribeira, Cidade Alta and Alecrim, pioneers in the service sector, noting that currently there is an ongoing process of decentralization in the city of such activities, to other areas of the urban fabric of Natal. Later, we studied the Avenues Bernardo Vieira to Roberto Freire Engineer, noting, in both the distribution of commercial activities and services, and issues related to transportation, traffic, tourism and socio-economic problems, identified them. Finally, testify that Natal, from the 1980s, underwent a process of decentralization of services, both to the south, and north of the city on the ball. In this process of decentralization we ascertain the role of public policies on transport and tourism, complementing the action of private enterprise, through the real estate market, on Avenue Roberto Freire Engineer.

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A aplicação de isolantes térmicos em sistemas construtivos promove vantagens com vistas ao conforto térmico de ambientes. E com isso, o aumento da produtividade em locais de trabalho, a sensação de bem-estar e a diminuição dos custos com climatização. A demanda por conforto ambiental, no âmbito da isolação térmica, somada ao advento de novas leis que regulam os requisitos mínimos de conforto, as exigências dos consumidores pela adoção de métodos de produção mais “limpos”, a fiscalização quanto à destinação de resíduos industriais, além da inserção de produtos no mercado com apelos ambientais, incentivaram o desenvolvimento da presente pesquisa. O presente trabalho trata da aplicação do poliuretano, visando comparar o desempenho térmico do derivado de origem vegetal (óleo de mamona) com adição de resíduo plástico termofixo em diferentes proporções (5%, 10%, 15% e 20%), com o poliuretano petrolífero, a lã de vidro e a lã de rocha através da análise de suas propriedades térmicas (condutividade térmica – k, difusividade térmica – e capacidade calorífica – Cp). . Após a realização dos ensaios, os compósitos estudados foram moídos e reutilizados como carga para novos compósitos. Com base nos resultados dos ensaios de propriedades térmicas, constatou-se que o material desenvolvido conduz menos calor que o poliuretano de petróleo, a lã de vidro e a lã de rocha, além de oferecer alta inércia térmica, bom desempenho térmico e baixo custo. Assim como foi comprovada a possibilidade de fabricação de novos compósitos para fins de isolamento, reutilizando os compósitos testados

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Propõe-se discutir, ainda que inicialmente, as dinâmicas de inserção de indígenas em cidades brasileiras e refletir acerca de suas percepções sobre o espaço urbano. O foco recai sobre o contexto amazônico (particularmente, a cidade de Manaus) e apresenta as percepções de um grupo de índiosBarésobre o lugar. Demonstro como, a despeito das desigualdades sociais no que tange ao acesso a direitos elementares e das formas de violência a qual estão submetidos, os Baréconstroem de modo singular seu cotidiano na cidade, cabendo reconhecer seu papel de agência nesse processo

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A melhoria do processo de extração da fécula de mandioca é um problema bastante discutido entre industriais e pesquisadores. Atualmente, para cada tonelada de raiz de mandioca processada obtêm-se por volta de 250kg de fécula e perde-se no resíduo fibroso cerca de 140kg de fécula que não foi extraída no processamento. Neste trabalho objetivou-se analisar o efeito de uma segunda extração em paralelo e o uso de soluções auxiliares na extração da fécula retida no resíduo fibroso (farelo), visando a melhoria no rendimento industrial. Foram avaliados quatro tratamentos utilizando-se: água (T1), solução de NaOH 0,2% (T2), solução água-álcool 10%v/v (T3) e solução água- Tween 80 0,002% (T4). A partir dos resultados obtidos foi possível concluir que a adição de soluções auxiliares não promoveu diferença significativa (p< 0,05) de extração em relação à água (T1), e que uma nova extração da fécula retida no farelo possibilitaria uma redução de cerca de 20% no teor de amido do farelo, o qual não é extraído no processo convencional.

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The work however presented try to make an analysis of the relation urban-agricultural in the context of the process of metropolization of Natal. On the basis of this approach searched to argue the estruturation of the Brazilian urban space and the relation with the agricultural one, evidencing an academic debate little contemplated, in view of that the space transformations guided by Brazilian industrialization had earned as endorsement a mere urban direction, fact that neglected factors more complex than they for the urban-agricultural relation in the context of the urbanization and, more recently, of the metropolization. Another important factor in the construction of the work was the contextualization of the urbanization of the Rio Grande do Norte, as well as of the metropolization of Natal, where if the significant presence of an agricultural reality made an analysis of the configuration metropolitan in the present time displaying that also remains and reproduces the metropolis, fact that conditions and justifies the treatment of the reality metropolitan for the bias of the urban-agricultural relation. The approach of this relation was directed for the agricultural nestings of the Region Metropolitan of Natal (RMN), understood as fragments agricultural in the context of the metropolis, in view of that a tenuous correspondence of these nestings with the metropolis in the direction of its integration was observed. As methodology one used bibliographical survey in periodic and books and collected secondary data-collecting next to the IBGE and to the INCRA and still were directed a field research where interviews next to the seated ones had been carried through. In this direction, one evidenced that the metropolization also absorbs and even though it reproduces the ruralidade that if verifies in the RMN finishing for mining the idea of an urban one that it excludes the agricultural one. In the case of the RMN, we have agricultural and the urban one exactly if conforming in one space that is metropolitan

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thèse de maîtrise, qui a été idealizée et exécutée à partir de la réunion et les relations dialogiques établies entre la géographie et l'histoire, et l'espace et le temps, a considéré l'environnement urbain comme le thème général et, comme la référence empirique, l'espace urbain de Caicó, incrusté dans les terres semi-arides du Sertão do Seridó Potiguar, plus précisément à la mi-sud de l'État du Rio Grande do Norte. Dans cet espace, à travers de recherche des fragments de mémoires acquis de diverses sources historiques, on a tenté de faire des investigations sur les transformations urbaines qui ont eu lieu dans la ville au cours des années 50 et 60 du XXe siècle. Ces transformations, dans l espace urbain de Caicó à un moment du pic de l'activité de développement de coton, reflétaient et conditionnaient les propres projets de modernization urbaine qui représentants des élites locales eurent conçu avec l'objectif de la construction d une ville idéal dans les regions isolées du Seridó: moderne, civilisé, progressive et capitale régionale du Seridó. Pour cette construction, les nouveaux équipements et services urbains ont passé du plan imaginaire à l espace réel, installés dans plusieurs quartiers de la ville en transformant le paysage urbain. Face à cette situation, cinémas, magasins, station de radio, énergie électrique, institutions de l'éducation, téléphonie, maison de soins infirmiers, usine de bénéficiement de coton, banques, politiques urbaines, hygiéniques et sanitaires, modes de comportement, sociabilités urbaines distincttes, parmi d'autres éléments géographiques se sont institués à travers la réalisation de certains idéaux de progrès social et dans un esprit de modernité urbaine, dans de nouveaux espaces et pratiques inventés, tramés et éprouvés sur les rochers et entre le cours d eau au milieu d'un quotidien urbain marqué par ruptures et permanence de certaines coutumes et habitudes antiques et de certains paysages et environnement ridé

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In view of the diversity and the heterogeneity of the existing cities in Brazil, our approach refers to the urban and non-metropolitan areas. Aiming to foment the studies on small cities e to apprehend the sociospatial configuration of the urban environment in such cities, this piece of work elaborates and analyzes the urban profile of the small cities of the Agreste Potiguar region, using as a theoretical reference landmark the production of the urban and regional space, from the decade of 1970 to 2000. Starting from this reference, this piece of work presents an urban sociospatial characterization of the small cities of the Agreste Potiguar region, with emphasis on the economic framework, on the population dynamics, on the main social data, culminating in the main characteristics of the local daily life. The study of the small cities of the Agreste Potiguar region makes it possible the comprehension of the problems that involve the cities of this size, above all, those inserted in economically fragile regions. In the analyzed period, the changes occurred in the productive structure of the State of Rio Grande do Norte triggered a great crisis in the economy of the Agreste Potiguar region. This aspect, allied to the insufficient performance of the public power, contributed to the sprouting of some sociospatial problems, amongst which may be distinguished: the economic fragility, the generalized unemployment, the lack of security and the urban infrastructure absence sufficient to take care of the social demand. Even facing the existing problems, the small cities must be seen as potential spaces, capable to promote the regional development. To do so, it is necessary a process of democratization of the public administration, an ample popular participation and the establishment of a new urban policy, that aims at the social promotion of the individuals, the guarantee of basic necessities and the access to the necessary services to a dignified life