Utilização do éster de soja como biolubrificante

The lubricants found in the market are of mineral or synthetic origin and harm to humans and the environment, mainly due to their improper discard. Therefore industries are seeking to develop products that cause less environmental impact, so to decrease mainly, operator aggression the Cutting Fluids became an emulsion of oil / water or water / oil. However, the emulsion was not considered the most suitable solution for environmental question, therefore the search for biodegradable lubricants and which no are toxic continues and so vegetable oils are seen, again, as a basis for the production of lubricants. The biggest problem with these oils is their oxidative instability that is intensified when working at high temperatures. The process transesterification decreases the oxidation, however changes some physical and chemical properties. Therefore soybean oil after the transesterification process was subjected to tests of density, dynamic viscosity, kinematic viscosity which is calculated from two parameters mentioned, flash point and acidity. Besides the physico-chemical test the soybean oil was subjected to a dynamic test in a tribometer adapted from a table vise, whose induced wear was the adhesive and ultimately was used as cutting fluid in a process of turning in two different materials, steel 1045 and cast iron. This latter test presented results below the mineral cutting fluid which it was compared in all tests, already in other experiments the result was satisfactory and other experiments not, so that chemical additives can be added to the oil analyzed to try equate all parameters and so formulate a biolubrificante not toxic to apply in machining processes of metalworking industry

Estudo das propriedades físico-químicas do biodiesel e suas influências na deterioração dos elastômeros aplicados no sistema de injeção dos motores diesel

The biodiesel use has become important due to its renewable character and to reduce environmental impacts during the fuel burning. Theses benefit will be valid if the fuel shows good performance, chemistry stability and compatibility with engines. Biodiesel is a good fuel to diesel engines due to its lubricity. Then, the aimed of this study was to verify the physicalchemistry properties of biodiesel and their correlations with possible elastomers damage after biodiesel be used as fuel in an injection system. The methodology was divided in three steps: biodiesels synthesis by transesterification of three vegetable oil (soybean, palm and sunflower) and their physical-chemistry characterization (viscosity, oxidative stability, flash point, acidity, humidity and density); pressurized test of compatibility between elastomers (NBR and VITON) and biodiesel, and the last one, analyze of biodiesels lubricity by tribological test ball-plan( HFRR). Also, the effect of mixture of biodiesel and diesel in different concentrations was evaluated. The results showed that VITON showed better compatibility with all biodiesel blends in relation to NBR, however when VITON had contact with sunflower biodiesel and its blends the swelling degree suffer higher influences due to biodiesel humidity. For others biodiesels and theirs blends, this elastomer kept its mechanical properties constant. The better tribological performance was observed for blends with high biodiesel concentration, lower friction coefficient was obtained when palm biodiesel was used. The main mechanisms observed during the HFRR tests were abrasive and oxidative wear

Caracterização do óleo de carnaúba para uso como biolubrificante

Lubricant is responsible for reducing the wear on the friction protect the metal against oxidation, corrosion and dissipates excess heat, making it essential for the balance of a mechanical system, consequently prolonging the useful life of such a system. The origin of lubricating oils is usually mineral being extracted from the petroleum. But the search for a new source of production of lubricants and fuels it is necessary to meet future demands and reduce the possible environmental damage. For this reason, looking alternative means to produce certain products derived from petroleum, such as biodiesel, for example. Returning to the realm of lubricants, also one realizes this need for new raw materials for their production. Vegetable oil is a renewable resource and biodegradable, and its use entails advantages in environmental, social and economic. The development of this project aims to characterize the carnauba oil as a lubricant plant, or biolubricant. To analyze the oil carnauba tests as checking density, flash point, fire point, viscosity, viscosity, acid number, pH, copper corrosion, thermal conductivity and thermal resistivity were developed. In addition, for conducting the wear on the friction and the gradient of the system temperature, the analysis equipment is designed for wear on the friction. Based on these results, it is observed that the oil carnauba show good correlation to its application as biolubricant

Estudo tribológico de biolubrificantes com adição de nanopartículas de óxidos (zinco e cobre)

Currently, vegetable oils have been studied for bio-lubricants base that fits the new environmental standards. Since, in a world full of finite natural resources, mineral oils bring consequences to the environment due to its low biodegradability and toxicity, also it is important to consider that synthetic oils have a high cost The aim of this work is to obtain a biolubricant additived with oxide nanoparticles (ZnO and CuO) for better resistance to friction and wear, which is not toxic to the environment and have better adherence under boundary lubrication. The methodology consisted in the synthesis of bio-lubricants (soybean and sunflower base) by epoxidation reaction. Then, some physical-chemical analysis in bio-lubricants are made to characterize theses lubricants, such as, density, acidity, iodine value, viscosity, viscosity index. Later, the lubricants were additive with nanoparticles. The tribological performance was evaluated by the equipment HFRR (High Frequency Reciprocating Rig) consisting of a wear test ball-plan type. The characterization of wear analysis was performed by SEM / EDS. The results show that bio-lubricants may be synthesized by reaction of epoxidation with good conversion. Tribological point of view, the epoxidized oils are more effective than lubricant additived with the oxide nanoparticles, they had lower coefficients of friction and better rate of film formation in the study. However, because they are environmentally friendly, bio-lubricants gain the relevant importance in tribological field

Otimização do fresamento de roscas internas com a técnica de interpolação helicoidal

In machining of internal threads, dedicated tools, known as taps, are needed for each profile type, diameter, and low cutting speed values are used when compared to main machining processes. This restriction in the cutting speed is associated with the difficulty of synchronizing the tool s rotation speed and feed velocity in the process. This fact restricts the flexibility and makes machining lead times longer when manufacturing of components with threads is required. An alternative to the constraints imposed by the tap is the thread milling with helical interpolation technique. The technique is the fusion of two movements: rotation and helical interpolation. The tools may have different configurations: a single edge or multiple edges (axial, radial or both). However, thread milling with helical interpolation technique is relatively new and there are limited studies on the subject, a fact which promotes challenges to its wide application in the manufacturing shop floor. The objective of this research is determine the performance of different types of tools in the thread milling with helical interpolation technique using hardened steel workpieces. In this sense, four tool configurations were used for threading milling in AISI 4340 quenched and tempered steel (40 HRC). The results showed that climb cut promoted a greater number of machined threads, regardless of tool configuration. The upcut milling causes chippings in cutting edge, while the climb cutting promotes abrasive wear. Another important point is that increase in hole diameter by tool diameter ratio increases tool lifetime

Desenvolvimento de um sistema a jato de plasma obtido em cátodo oco para deposição de filmes finos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Análise de células t regulatórias foxp3+no líquen plano oral

T regulatory cells have the function of controlling immune responses and maintaining self-tolerance. The FoxP3 has been considered the most specific marker for Treg cells. The aiming of this paper was to evaluate the immunoexpression of FoxP3 in the inflammatory infiltrate from oral lichen planus (OLP) and to compare it with the infiltrate in fibrous inflammatory hyperplasia (FIH) and then, between reticular and erosive forms of OLP. The samples were composed by 32 cases of OLP (17 reticular and 15 erosive) beyond 10 cases of FIH that were submitted to immunohistochemistry staining for FoxP3. Localization of the staining was classified in underepithelial and intraepithelial and the amount of FoxP3+ cells was evaluated through cells counting in 10 consecutive fields, at 400x power magnification. The values were expressed in mean ± standart deviation, and submitted to statistical tests with 5% of significance level. It was observed a statistical significant difference in the amount of FoxP3+ Treg cells between the two combined forms of OLP (1,6 ± 2,2) and the FIH (0,5 ±0,4) (P<0,05). This maybe could be explained by immunological mechanism of OLP, which involves a permanent antigenic induction likely with consequent perpetuation of lesion, eliciting the proliferation and constant recruitment of Treg cells. Otherwise, FIH presents a different etiopathogenesis, in which there is also generation of a variable inflammatory infiltrate, however qualitatively distinct from that seen in OLP. The erosive form of OLP exhibited a greater number (1,7 ± 2,4) of FoxP3+ Treg cells than reticular form (1,5 ± 2,1). These alterations could have relation with the great disease activity verified in erosive OLP, or also, with abnormalities in the regulatory function of Treg cells that could cause the increase observed. Considering the capacity already well established in the literature, both about Treg cells in modulating immune responses, as in the oral mucosa in showing great potential for regeneration, it is suggested that the possibility of development and implantation of immunotherapeutic strategies that regulate the frequency and function of these cells, may help in future treatment of immune-mediated inflammatory diseases such as OLP

Análise da resposta th17 em líquen plano oral

Th17 cells have been strongly associated with the pathogenesis of several autoimmune and inflammatory diseases. IL-17 and IL-23 are important cytokines associated with this lineage. The aim of this study was to analyze, through immunohistochemical methods, the immunoexpression of IL-17 and IL-23 in the inflammatory infiltrate of oral lichen planus (OLP) lesion compared to that of inflammatory fibrous hyperplasia (IFH) and between clinical forms reticular and erosive of OLP. The sample included 41 cases of OLP, of which 23 were reticular and 18 erosive and 10 cases of IFH. The results were subjected to nonparametric statistical tests with a 5% significance level. In OLP lesions histomorphological analysis, the most common findings were: hyperparakeratinization, specimens with atrophic epithelium in erosive clinical form (p = 0.011), epithelial projections in most of reticular type of lesions, in addition Civatte bodies were identified in most samples of both clinical forms. For immunohistochemistry analysis, five fields with strong immunoreactivity for IL-17 and IL-23 were photomicrographed at 400x magnification, images were transferred to a computer where with ImageJ software®, lymphocytes that exhibited cytoplasmic immunostaining for these cytokines were counted. A mean was established after for each case. There was no statistically significant difference in the number of imunopositive lymphocytes for IL-17 and IL-23 among the group of OLP and IFH group, however a larger amount of lymphocytes imunopositive for IL-17 was found in the LPO group (p = 0.079) and significantly higher amounts of those lymphocytes were found in the erosive OLP when compared to the group of reticular OLP and IFH (p = 0.019). Furthermore, a marker epithelial immunopositivity for IL-17 was observed in OLP group. Although the results of this study do not permit the forceful assertion about the participation of Th17 lineage in OLP lesions, the findings of immunopositive lymphocytes counting for IL-17 and IL-23, which are potent proinflammatory cytokines, together with the the marked epithelial immunopositivity found for IL-17 in this study, suggest a possible role of this lineage in the pathogenesis of this disorder

Avaliação da angiogênese em lesões de líquen plano oral e pênfigo vulgar

Oral lichen planus and pemphigus vulgaris are chronic diseases mucous membrane immune of unknown aetiology that can be observed affecting to the oral mucous. A relevant as regards neoplasies the role angiogenesis in the inflammatory chronic disease pathogenesis as it provides a substancial interest can be considered as being an activity diseases marker; besides being through specialised research of this angiogenic process to improve of understanding pathogenic mechanism. This research proposes to assess angiogenic active through of antibody immunohistochemistry expression antiCD34 antibody in 26 OLP of reticular cases, 14 OLP erosives cases, 18 of PV cases and 15 specimens of normal oral mucosa. The result was submitted non-parametric tests of 5% significance level. It is not statistically significant correlacion was seen regarding between average vessels. However, only be effectively observed the median of OLP cases was larger than pemphigus vulgaris in fact proved average larger than oral normal mucosa (p=0,280). Regarding the microvascular count of CD34 concerning clinic form oral lichen planus (reticular and erosion) increased emphasis is more cross-border average for the form erosion clinic. Despite of the statistic tests could not be more effective (p=0,720). Even though, the results of the research is not sufficient to enable to consider of angiogenic process in the pathogenesis and lesions progression of oral lichen planus and pemphigus vulgaris, we suggest this process is present in both forms lesion, however, more studies must be made in the near future in order to prepare a well-founded proposal

Motivação para o trabalho: um estudo com os profissionais de saúde das unidades básicas de saúde do município de Natal RN

This thesis studied the motivation to work among health professionals of the Basic Unities (BUH) in the health network of the city of Natal (RN). It was understood that the work motivation is a process. Then, the expectation theory was applied and motivation components (results of work, expectative, valence, instrumentality, and motivational force) were used to analyses. It s understanding the motivation as multifaceted phenomenon, the psycho sociological perspective was adopted. The research was developed in two phases: one with application of Work Motivation and Meaning Inventory (WMMI), and another with interview. In the first phases, the analysis of results revealed that the major factors contributing to increase the motivational force to health professionals in the BUH´s are: in valence, Self Expression and Personal Realization (VF2), Personal and Family Survival (VF3); in expectative, Self Expression and Work Justice (EF1), Safety and Dignity (EF2) and Responsibility (EF4); in instrumentality, Involvement (IF1) and Recognition and Economic Independence (IF4). In opposition, the factors that more contribute to reduce the motivational force are Wear and Dehumanization factors in valence (VF4), in expectative (EF3), and in instrumentality (IF4), behind the Work Justice Factor (IF2). Basing in content analysis of interviews, it was possible to associate by equivalence, the senses presented by health professionals with obtained results of first phase, indicating that the results of second phase corroborated and complemented those of first one. This possibility broadened the comprehension of the studied phenomenon. In speaking of the respondents, it was visible the presence of contents showing that they perceive the Health System and BUH´s in degradation. In the first phase, the participants´ instruction also predict the results in motivation, and in the interviews can be saw that the instruction is associated with the opportunities in outside of system. As work motivation is a process, the impact of personal and occupational characteristics tend to interact with contextual aspects. It was concluded the majority of health professionals present the moderated motivational force, but it was falling because they experience and perceive a degrading context with work condition increasingly unfavorable.

A motivação e o significado do trabalho de bancários: estudo comparativo entre dois momentos do processo de reestruturação produtiva

This master s dissertation deals with motivation and the meaning of work amongst bank employees. This is done considering a cognitive perception. Work is understood here under a social and subjective comprehension, once it deals with significance attribution. Motivation is the process that rules choice of the different possibilities of individual behavior, all of which according to the Expectation Theory. This study aims to analyze the implications of the productive restructure, since it is related to technological innovation, organizational changes and management, in motivation and work significance. Thus, the objective of the research is to verify motivational differences and the meaning of work amongst bank employees. This is done in two distinct moments of the productive restructure of bank employees in Natal-RN. The research is divided in two parts. In the first one, changes that occurred in banks between 1999 until 2005 were identified by the means of interviews with 7 bank managers. The analyzed perspective was training intensifying, quality emphasis of customer attendance, the use of automation/technology, staff stabilization, change in staff profile, work intensification, etc. In the second study the Inventory of Motivation and Work Meaning was applied. Thus, questions related to work focus, social demographic data, in 187 bank employees were dealt with. The collected data was compared to data from previous work. It was observed that productive restructure has a reflection in the meaning of work increasing self-expression, economical reward, and responsibility in work conditions. All of the item mention beforehand maintain the level of inhumanness and consummation and respond as being the characteristics of the real work environment. On the other hand, bank employees value less justice, self-expression and more the survival perspective, implying instrumental values to work. As for motivation, it is increased among bank employees. These employees have greater expectations that their work produce results since they believe in their interference in work results

Sistema especialista fuzzy para dimensionamento de bombeio mecânico

Despite the emergence of other forms of artificial lift, sucker rod pumping systems remains hegemonic because of its flexibility of operation and lower investment cost compared to other lifting techniques developed. A successful rod pumping sizing necessarily passes through the supply of estimated flow and the controlled wear of pumping equipment used in the mounted configuration. However, the mediation of these elements is particularly challenging, especially for most designers dealing with this work, which still lack the experience needed to get good projects pumping in time. Even with the existence of various computer applications on the market in order to facilitate this task, they must face a grueling process of trial and error until you get the most appropriate combination of equipment for installation in the well. This thesis proposes the creation of an expert system in the design of sucker rod pumping systems. Its mission is to guide a petroleum engineer in the task of selecting a range of equipment appropriate to the context provided by the characteristics of the oil that will be raised to the surface. Features such as the level of gas separation, presence of corrosive elements, possibility of production of sand and waxing are taken into account in selecting the pumping unit, sucker-rod strings and subsurface pump and their operation mode. It is able to approximate the inferente process in the way of human reasoning, which leads to results closer to those obtained by a specialist. For this, their production rules were based on the theory of fuzzy sets, able to model vague concepts typically present in human reasoning. The calculations of operating parameters of the pumping system are made by the API RP 11L method. Based on information input, the system is able to return to the user a set of pumping configurations that meet a given design flow, but without subjecting the selected equipment to an effort beyond that which can bear

Poluição sonora: um grave problema na cidade de Mossoró-RN

In the latest decades, we have observed some environment alterations of big proportions in our planet. Sound pollution, visual pollution, water pollution, air pollution, soil pollution, all the principal kinds of environment pollution have raised in the path of economy development. In Mossoró it is not different; the environment has suffered a long and continuous damage caused by predatory abuse. The river is polluted, the ciliar vegetation of Carnauba was totally altered and with it a part of the local fauna disappeared. In fact, the city urban environment has, and continues to be, deeply altered and the sound pollution is a reflex of the urban modifications undergone in the city as time goes by. Through bibliographic review, the gauging of noise and fieldwork, this research project had the objective of analyzing the principal activities that cause sound pollution in the urban perimeter of the city of Mossoró, RN, emphasizing the causes, effects and spacial distribution of the polluter agents, as well as understanding how the environmental laws treat the sound issue in the urban environment of the city. The President Dutra avenue, where popular events of Mossoró take place and an important access for the city, was the chosen place to study this pollution that became, recently, another hindrance that interferes on the life quality of the local population. The results of this brief research emphasizes the urgency to alert society, specially about the importance of law and public organs that are located in our city, therefore solving problems such as the aforementioned above

Potencialidade à degradação na microbacia Riacho Passagem/RN

A degradação dos recursos naturais é talvez o principal problema da região do semiárido brasileiro, e essa degradação é principalmente resultante das perdas de solo, decorrente do processo erosivo. Na busca de melhor conhecer esta problemática vem sendo empregado o processo de modelagem ambiental, cujo objetivo é identificar e propor soluções para a degradação dos solos. Nesse sentido, o trabalho aplica o modelo da Equação Universal de Perda de Solos (EUPS), desenvolvido nos Estados Unidos ao longo da década de 1950, agregado as ferramentas de geoprocessamento, informações de sensoriamento remoto e Sistemas de Informações Geográficas (SIGs). A área de estudo é a Microbacia Riacho Passagem localizada na região oeste do Estado do Rio Grande do Norte, a microbacia tem uma área de 221,7Km² e esta inserida no semiárido, região Nordeste do Brasil. A metodologia utilizada consiste: em agrupar as variáveis da EUPS no ambiente SIG utilizando imagens de satélite, levantamentos bibliográficos e trabalhos de campo. Para determinação das extensões das vertentes foi empregado o Modelo RAMPA, e para adequar a EUPS as condições da área de estudo, foram realizados ajuste através de modelos estatísticos, aperfeiçoando o trabalho e os resultados gerados pelo modelo. Ao fim do processo foi desenvolvida uma pseudo linguagem no aplicativo Linguagem Espacial para Geoprocessamento Algébrico (LEGAL) disponível no software SPRING versão 5.1.2 servindo de suporte para o processamento das informações contidas no banco de dados, base da EUPS. Os resultados demonstram que inicialmente é necessário delimitar com precisão o período seco e chuvoso, informação fundamental para a EUPS, uma vez que o trabalho busca identificar a perda de solo por erosão hídrica. O modelo RAMPA apresentou-se satisfatório e com elevado potencial de aplicação na determinação dos comprimentos de vertentes utilizando imagens de radar. Quanto ao comportamento das extensões de vertentes, na microbacia, o mesmo apresentou uma pequena variação na porção leste, maiores vertentes, área próxima a desembocadura. Após a aplicação do modelo o valor máximo de perda de solo foi 88 ton/ha.ano com núcleos localizados no NEOSSOLOS LITÓLICOS e o mínimo 0,01 ton/ha.ano localizado no domínio dos LATOSSOLOS e NEOSSOLOS FLÚVICOS. A erosão provoca diminuição do perfil de solo, principalmente nos NEOSSOLOS LITÓLICOS, resultando em alteração no balanço hídrico e conseqüentemente aumento da temperatura do solo, podendo desencadear a desertificação. Os resultados e a metodologia do presente trabalho poderão ser aplicados na busca pelo desenvolvimento sustentável, na região do semiárido brasileiro, auxiliando na compreensão do binômio uso do solo e capacidade de suporte do meio natural.

Alterações ambientais em Parelhas, Rio Grande do Norte: metais pesados em sedimentos de drenagens e percepção de comunidades rurais em relação a mudanças na paisagem

The conservation of natural resources is essential and constitutes the main subject of many researches, which characterize important aspects concerning the environmental alterations in the ground, water, landscape and socioeconomic information. This study aimed to investigate the anthropogenic input of heavy metals in the environment, in the area of the Parelhas dump site and in part of the Seridó River and to determine the concentration of heavy metals in the sediments. This can result in risk to the environment and human health. In addition, we sought to establish the socioeconomic profile of rural communities adjacent to Seridó River and to comprehend the perception of these dwellers about the changes in the places they live. The area of this study is located in the city of Parelhas/RN, in the centralsouthern part of the State, in the micro-region of the Oriental Seridó. This area comprehends the place where the dump site is located, next to RN 086, the Caldeirão dam, the Quintos river called by local citizens Caldeirão creek and part of Seridó river, perpetuated by the Boqueirão dam, which crosses the city and it includes the rural communities of Almas, Domingas, Sussuarana II and Colonos. Regarding the study with bottom sediments, the samples were collected and taken to the laboratory of geochemistry, where they were dried, sieved, weighted and submitted to weak acid attack. The analysis of heavy metals was held by Atomic Absorption Spectrophotometer - Flame AAS. We applied 23 closed questionnaires constituted by 38 questions to collect informations in the rural communities, oriented to establish the socioeconomic profile and the environmental perception of the participants. The participants were distributed in the communities of Almas (1), Domingas (2), Sussuarana II (10) and Colonos (10). Most of them presented similar socioeconomic profiles. They are from 45 to 60 years old and live in these localities for 20 to 30 years or more. The families are composed by 3 or 4 people; the agriculture is the main activity, livestock is the secondary and 48% of them earn the minimal wage. Regarding the environmental perception, the participants can realize some changes in vegetation, soil, water and landscape. People living longer in the community, and with more years of experience on the local reality can perceive the depletion of the soil, pastures and changes in the landscape. These changes portray how the place was previously and what it represents today. The perception of these changes, besides the environmental ones, includes others concerning the increasing number of dwellers in the last years, as well as the number of houses. The changes happened through activities developed by the dwellers over the years, including agricultural practices, livestock, grass planting and even the cultivation of cotton. The study provided the acquisition of new data about the environmental reality of this region. It can subsidize the definition of public policies that can be implemented from the perspective of conservation of water resources and of the coexistence and survival of man in the semi-arid