Utilização da mínima quantidade de lubrificante (MQL) com água no processo de retificação cilíndrica em cerâmica avançada com rebolo de ligante resino cerâmico/metálico

Pós-graduação em Engenharia Mecânica - FEB

Transferência de calor inversa do método convencional e do otimizado de lubri-refrigeração na retificação plana tangencial

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Avaliação da resposta imune sistêmica e compartimentalizada em pacientes portadoras de cãncer de ovário: sub-titulo / (se houver)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um estudo sobre as operações unitárias de agitação, troca de calor em tanques e mistura de pós

De todas as operações, a agitação de fluidos, a troca de calor em tanques e a mistura de pós são, sem dúvida, as mais usuais, principalmente, na indústria de alimentos. Embora exigindo um estudo em separado, é comum estas operações unitárias estarem presentes, em instantes diferentes, no mesmo processo de fabricação. O propósito deste trabalho é enfatizar procedimentos de projeto para problemas práticos nas indústrias de processos envolvendo estas três operações. O modelo matemático proposto para a agitação de fluidos foi aplicado na substituição das tradicionais âncoras por impelidores de pás retas e inclinadas no processamento do suco concentrado de laranja. Observou-se que o tempo de permanência do suco no tanque de resfriamento caiu de quarenta para cinco minutos em decorrência da maior ação de mistura provocada pelas pás retas. O modelo proposto acompanha bem as exigências de potências requeridas pelo suco na medida em que é resfriado...(Resumo completo, clicar acesso eletrônico abaixo)

Métodos diagnósticos para detecção da Leucemia viral felina

The feline leukemia virus (FeLV) was described in 1964 by William Jarrett and collaborators wen find viral particles attached to the membrane of lymphoblasts in cat with lymphoma. The virus belongs to the family Retroviridae, subfamily oncornavirus. With worldwide distribution, the occurrence of FeLV has 1.6% in healthy cats and 10.8% in sick cats in Brazil. The mortality of persistently viremic animals in catteries is about 50% in two years and 80% in three years. In catteries that have endemic feline Coronavirus (FCoV), FeLV and / or Feline Immunodeficiency Virus (FIV), the FeLV infection has greater contribution to mortality. The test for infection and FeLV positive cats segregation is the main way to prevent the spread of infection. The diagnostic methods are based on clinical signs and changes compatible with FeLV infection observed by physical examination, complete blood count, X-ray, bone marrow aspirate and biochemical. The viral p27 protein is produced in infected cells in high amounts and is found in abundance in the cytoplasm and in body fluids enabling diagnosed methods such as enzyme-linked immunosorbent assay - ELISA and direct immunofluorescence, detection of viral genome (Chain Reaction Polymerase - PCR) and detection of the virus by virus isolation. Although diagnostic tests are highly sensitive, it should be made more than a confirmatory test, especially serological due to variable characteristic of the progress of infection

Análise de uma câmara de combustão em escala piloto através de fluidodinâmica computacional

This work aims to examine, the behavior of a combustion chamber in pilot scale, coupled to a regenerative burner. The objective is to obtain a computational domain capable of supporting a simulation of conventional combustion and flameless combustion regimes. The objective is to obtain independence of mesh, analysis of the velocity fields of the fluid within the chamber, temperature and concentration profiles of the species emitted during the combustion process

Efeito da aplicação do fluido de corte na usinagem da superliga Nimonic 80A

The nickel alloys have a chemical composition with high tenor of alloy elements which are responsible for the material's mechanical and thermal properties, but also are the main causative of problems during the machining, making the process difficult. The objective of this work is the study of the machining by external cylindrical turning of the nickel based alloy Nimonic 80A, seeking the machining optimization of this alloy, seeking the best condition of lubricant fluid use, providing real increases of productivity without the need of investments in new production means. Besides, the results of this work should offer more detailed information regarding the behavior of this alloy in relation to machining by turning. The machining experiences were accomplished in a specimen of the nickel alloy, considering the machining parameters: cutting speed (75 and 90 m/min), cutting depth (0,8 mm) and feed rate (0,15 and 0,18 mm/v). The valuations were accomplished in a CNC lathe and tools with of hard metal inserts. After each stage of the turning the measures of the cutting length were accomplished, of the waste of the tools through a magnifying glass (8x) and the roughness of the specimen evaluated in each phase of the process, with the aid of a portable roughness meter. Through light optical microscopy it was possible to observe the wear of the cutting tools for each appraised condition. The roughness values, Ra and Ry, for the appraised conditions were always superiors to the theoretical values. After analysis of the results it was possible to end that, the best acting for this work strip tested it was obtained for ap=0,8mm: f=0,15mm/rev and VC=75m/min, what resulted in a larger cutting length (1811 m)

O estudo da usinagem em torneamento da superliga à base de níquel Pyromet 31v

The search for materials with higher properties and characteristics (wear resistance, oxidation, corrosion, etc.) has driven research of various materials. Among the materials that are being studied with such properties and characteristics are super alloys based on nickel which has an important role in the aeronautical, automotive, marine, production of gas turbines and now in space vehicles, rocket engineering , experimental aircraft, nuclear reactors, steam-powered plants, petrochemical and many other applications because besides having all the characteristics and properties mentioned above also have an excellent performance at high temperatures. The super alloy based on nickel studied in this work is the super alloy Pyromet 31v normally used in the manufacture of exhaust valves in common engines and diesel engines of high power by cater requirements such as mechanical strength and corrosion resistance at temperatures of approximately 815 ° C. The objective of this work is to produce results to demonstrate more specific information about the real influence of coatings on cutting tools and cutting fluids in turning and thus promote the optimization of the machining of these alloys. The super alloy Pyromet 31v was processed through turning, being performed with various machining parameters such as cutting speed, feed rate, depth in conditions of Minimum Amount of Fluid (MAF), abundant fluid, cutting tools with coating and without coating in early in his work life and with wear. After turning were obtained several samples of chips and the part generated during the machining process, was measured roughness of the material, subsequently made macrostructural analysis of the tools used order to detect possible wear and microstructural analysis of samples collected being that the latter was used for Optical Microscopy, Scanning Electron Microscopy (SEM) and ... (Complete abstract click electronic access below)

Estudo da fluidodinâmica de uma mistura de sólidos em um leito fluidizado gás-sólido

Fluidization consists in a bed of solid particles acquire fluid behavior by using a fluid (in this case air) flowing through the solid particles. Because of this, it can be a good mix of these materials, as well as to show increased rates of heat and mass transport. The fluid flowing through the spaces between the particles gives an interstitial velocity, that if is too low does not cause movement of the particulates. The gradual increase in speed will generate small vibrations between the particles promotes its fluidization. Our study focus in the fluid state of solid bed , when the fluid velocity reaches a state where the drag forces are sufficient to support the weight of the solid particles making these solids behave like fluids . Knowledge of the minimum velocity required to fluidize that particles is of great importance since below this speed there is no fluidization, and far above it, the solids are carried out of the bed. The fluidized bed reactor is widely used in physics and engineering, particularly in gas-solid fluidization, with emphasis on thermochemical processes

Estudo da usinagem por torneamento de ligas de alumínio

The non-ferrous materials have got so many mechanical, physical and chemical advantageous properties so that is provided to them consolidated position in industry. In this context, aluminium alloys have been seen a lot on many applications of engineering areas – specially on automotive, aeronautical and aerospace due to their main properties such as low density, high corrosion resistance, favorable structure weight / material resistance relation, among others characteristics that are mencioned through this study. This study aims to analyze the aluminium alloys behavior on a general context when they are used on turning process, taking for examples the 6262 and 7050 aluminium alloys. In this way, the analysis studies the datas obtained during the turning tests realized on 3 steps each one; those datas are concerning the medium and total rugosities – obtained with the assistance of a portable Surface Roughness Finish Tester, as well as the chips obtained during the tests - visual analysis, and the cutting tools wear – with the assistance of an optical microscope, under different conditions of application of cutting fluids (dry machining, application of coolant in abundance and MQL – Minimum Quantity of Lubricant). The results concerning this study show detailed information about influence of cutting fluids on the machining by turning of the aluminium alloys related on this work and also about aluminium alloys in general when they are used on turning processes with different conditions from one another. By this way, it was evident the MQL technique is the best one for the 6262 alloy. However, for 7050 alloy, it was evident that the dry machining is responsible for the best results

Avaliação da permeação cutânea in vitro de sistemas nanoestruturados contendo ácido kójico

O processo de envelhecimento origina uma série de alterações na pele, dentre elas as o estresse oxidativo e as discromias. O ácido kójico tem a capacidade de atuar no tratamento do envelhecimento cutâneo em virtude de sua atividade ferro-quelante e de promover a despigmentação da pele devido inibir a tirosinase, impedindo a formação da melanina. Sistemas de liberação controlada de substâncias ativas, como os sistemas líquido-cristalinos, tem a propriedade de modular a permeação cutânea de fármacos, além de melhorar a sua ação. O presente trabalho tem como objetivo desenvolver e caracterizar um sistema líquido cristalino constituído por água e isonomanoato de cetoestearila (óleo), e estabilizado com o tensoativo álcool cetílico etoxilado e propoxilado contendo ácido kójico, avaliando sua permeação cutânea in vitro. A partir da construção de um diagrama de fases, foram selecionadas três formulações caracterizadas microscopicamente como CLs de fase hexagonal, denominada de A (35% O, 50 % T e 15% A), B (30% O, 50 % T e 20% A) e C (20% O, 50% T e 30% A), para prosseguir com o estudo, que consistiu na incorporação do ácido kójico na concentração de 2% e a realização dos ensaios de textura, bioadesão, reologia e de permeação e retenção cutânea in vitro. O ensaio de textura demonstrou que a formulação B com valores intermediários de água e fase oleosa apresentou valores intermediários de dureza, compressibilidade e adesividade, ideais para aplicação tópica. O ensaio de bioadesão mostrou que com o acréscimo de água na fórmula a força bioadesiva aumentou, o que pode melhorar a fixação do produto na pele do usuário. O ensaio reológico evidenciou que há aumento da viscosidade com acréscimo de água na formulação e que os sistemas analisados tratavam-se de fluidos pseudoplásticos com tixotropia tempo dependente... (Resumo completo, clicar acesso eletrônico abaixo)

Modelagem e avaliação de um sistema de refrigeração por absorção para residências e instalações de pequeno porte

This work presents a study of the absorption refrigeration system and the modeling and evaluation of two cycles using the binary solutions water-lithium bromide and ammonia-water for an equipment to be used in small size plants like residences. The study and evaluation aims the complete understanding of all parts of the system and the influence of each one of them as well as the spread of the knowledge to raise the use of this type of equipment in all sizes in order to decrease the energetic consumption of plants of all scales and making viable the alternative sources. The study is done in each element of the cycle separately and in some auxiliary equipments required in the operation such as the main power source, the solar collector. The software used for modeling, with emphasis on thermal part, was the EES (Engineering Equation Solver), that permitted the thermal balance calculus and acquisition of the used fluids properties. The results obtained for the equipment shows the system is more complex than the widely used in business, however, it can be viable and represents an alternative to increase the energetic efficiency

Avaliação de funcionamento das bombas hidráulicas do sistema de tratamento de efluentes da Empresa Parker Hannifin

On the field of the projects of hydraulic systems exists a lot of worries when we talk about the calculate of hydraulic pumps. In this case some facts must be considerate: length of tubes, fluid characteristics, height gauge, temperature, pressure, characteristics of tubes, flow required and others. For that mathematic calculates must be developed with the objective to optimize hydraulic pumps and agree to find an ideal machine (that don't requires more energy than necessary or less energy than it requires; that is the more critical case, cause exists the risk that the fluid pumped do not agree to become in your destiny). The wrong calculate of this machine can super-size its, bringing an excessive energy consumption. Actually it's an important subject because we are in the age of lack of energy what turn it more expensive. So the correct sizing of a hydraulic pump is connected with the fact that you have to uses the enough energy resources avoiding waste. The calculate of ideal pump in the pumping system is studied during years and a lot of specialists in this subject develop equations and theories to calculate its. Some researches study about this subject and all of them become to the same conclusion: to find the ideal pump we have to know the characteristics of fluid (cinematic viscosity), the required flow , overall yield (overall of motor x overall of pump) the high gauge or discharge pressure and the loss of repression. The pressure drop can be calculated with different theories: using Hazen-Williams, Darcy e Weisbach or Chézy (1775 - that starts the researches to calculate the pressure drop). Although the most used theory and what is most near to reality is the Darcy's equation. So, in this job the Darcy's equation were choice to calculate the drop pressure that consider what kind of flow we are studying: laminar or turbulent. The determination of the best pump to be used in the ... ( complete abstract click eletronic access below)

Expressão e localização de aquaporinas no epidídimo do gerbilo, Meriones unguiculatus, em diferentes fases do desenvolvimento pós-natal

Aquaporins (AQPs) are membrane protein channels expressed in a wide variety of cells and tissues that are involved in the transport of water. In the male excurrent duct, the movement of fluid and solutes across the epithelium is essential for establishing the proper luminal environment in which sperm mature and are stored. The initial aim of the present propose is to localize AQP 2 e 9 in epithelium of the initial segment, caput, corpus and cauda epididymidis in Mongolian gerbil during postnatal development (10, 30, 60, 120 and 300 days), observing possible changes in the pattern of expression of the AQPs along the postnatal development. The animals will be killed by inhalation of carbon dioxide. After euthanasia, the epididymis will be removed and the different regions will be isolated. The biological material obtained will be processed in accordance with the routines of histological techniques and imunnohistochemistry to study the expression and localization of the AQPs 2 and 9. The results obtained will be analyzed and photographed in conventional light microscope

Estudo dos parâmetros físicos na fluidização em um leito gás sólido

Through measurements of basic parameters for determining the fluidization regime, as particle size, minimum fluidization velocity, bed porosity, etc., This paper analyze the mass distribution of the phases of the bed to be discussed in relation to: the flow gas physical properties of the solid particles and the forces acting on the solid particles circulating within the bed, as the weight force, buoyancy and drag forces (Stokes' Law). Due to the weight force is constant, open up the discussion about which of the other two forces, buoyancy and drag force, influencing the behavior of the bed. We used the photographic method to realize the statistical analyzes. Therefore, we can conclude what changes can be made more convenient in fluidizing the bed to obtain the highest efficiency for a good mixing used in industrial processes