Estudo, constru����o e caracteriza����o de diodos org��nicos tipo Schttky

During the twentieth century the inorganic electronics was largely developed being present in various industrial equipment or household use. However, at the end of that century were verified electronic properties in organic compounds, giving rise to the field of organic electronics. Since then, the physical properties of elementary devices such as diodes and organic transistors have been studied. In this work was studied the properties of diode devices fabricated with a semiconductor polymer, the poly-o-methoxyaniline (POMA). Devices containing electrodes of Au and Al were fabricated with semiconductor polymer of different doping levels. We found that the rectifying behavior for the heterojunctions metal/polimer are reached only for high doping level (with conductivity greater than 1,77. 10-9 S / cm), which gives the devices characteristic of a Schottky diode. The rectifying behavior was observed for electric fields of low magnitude, below the operating field (~ 600 V/cm), while for electric field greater than 600 V/cm the a linear behavior I vs.V was obtained. We determined that this Ohmic behavior arises from the charge transport over the volume of the semiconductor material after the lowering of the metal/semiconductor barrier. In devices with weakly doped semiconductor, the electrical resistance of the volume becomes high and the process of charge transportation is dominated by the volume, for any intensity of the applied electric field

Dimensionamento de trocadores de calor aplicados �� refrigera����o da ��gua do molde de um processo de lingotamento cont��nuo

This study aims to determine the most suitable type of heat exchanger to be applied to the water cooling the mold of a continuous casting process. Basically been studied four types of heat exchangers: shell and tube operating in counterflow, shell and tube operating in parallel flow, plate type and operating counterflow and plates operating in parallel flow. Initially is displayed design of heat exchangers for the conditions of the proposed application. With the heat exchangers dimensioned comparisons were made in order to set the heat exchanger more suitable for application. In the study, one comes to the conclusion that the plate type heat exchangers operating shows counterflow major advantage for this application

�� de pequenino que se torne o pepino: o processo pedag��gico de constru����o das regras de trabalho e de conduta, em duas salas do Proepre

O desenvolvimento da moral na crian��a inicia-se muito cedo, na medida em que vivencia experi��ncias sociomorais. Piaget observou num jogo infantil fases do desenvolvimento moral relativos �� pr��tica e a consci��ncia da regra, a partir das quais �� poss��vel fazer uma analogia com toda a sociedade. A escola �� um espa��o privilegiado para manifesta����es de car��ter eminentemente morais, podendo assim influenciar significativamente no desenvolvimento moral dos sujeitos. Uma pr��tica comum nesse sentido �� o estabelecimento de combinados de regras nas classes de Educa����o Infantil. Assim objetivou-se neste trabalho estudar como essa forma de constru����o de regras tem se constitu��do. Para tanto se realizaram observa����es sistem��ticas em duas salas de aula em escolas p��blicas em um munic��pio do interior de S��o Paulo (em que se implantou o PROEPRE) e se aplicou question��rio ��s professoras a fim de caracteriz��-las enquanto sujeitos de pesquisa. Tais observa����es ocorreram entre fevereiro e maio de 2009, em momentos distintos da rotina de cada classe. Os dados coletados nos permitiram concluir que o tempo de experi��ncia e forma����o dos sujeitos n��o se constitu��ram necessariamente em fatores relevantes para o tipo de trabalho desenvolvido com rela����o �� constru����o de regras em suas salas de aula. Conclu��mos tamb��m que a maneira com que os professores conduziram a constru����o de regras com seus alunos n��o contribuiu significativamente para o desenvolvimento moral das crian��as e para a supera����o da heteronomia e egocentrismo infantil segundo o referencial piagetiano

Avalia����o da tenacidade �� fratura em juntas soldadas circunferenciais de tubula����es de processo

This work aims to analyze the toughness of a welded joint in the presence of a crack through the analysis of maximum tension the material can withstand the presence of this type of defect, since a discontinuity is likely to occur in this type of joint and its detection and its design is simple, using non-destructive testing techniques. The study will be conducted through the CTOD test - Crack-Tip Opening Displacement, with type specimens SE (B) - Single Edge Bend taken from a weld in the L-C position in relation to the length (longitudinal axis) of a test tube. The main idea is to simulate the welding conditions for the manufacture of industrial pipes, made in boiler shops (pipe-shop) within petrochemical plants. These pipes are often subject to operation with flammable and toxic subjected to high pressures and temperatures, where one can break the line can cause irreparable damage to the plant, the environment and the health of surrounding communities. With this study we evaluate whether the weld metal has the same properties as fracture toughness of the base material. This study shows the importance of using a qualified welding procedure for performing quality welds while maintaining the properties of the fracture toughness of the base metal. It was found from the results of tests using a welding procedure described for carrying out welding ensures mechanical properties very close to the base metal, which in terms of design is great, since one can ensure that the weld will the same characteristics of the base metal specified for the assembly of the pipe

Aplica����o do m��todo desirability para otimiza����o de processo com m��ltiplas respostas

Currently, the competition between organizations in the pursuit of consumer preference has become increasingly fierce. In addition, consumers have become increasingly demanding due to high speed with which innovations occur, leaving the companies meet and sometimes surpass those expectations In this context, there is the necessity to use methods as mathematical models capable of dealing with the optimization of multiple responses simultaneously. In this context, this study presents an application of techniques of Design of Experiment in a machining process of a NIMONIC 80 alloy, a ���superalloy��� that has thermal and mechanical properties that make its machining difficult and in order to do this, the Desirability Function was used. As they are determining conditions in the machining capability of the alloy, the roughness and the cutting length were considered as variable settings, and the factors that can influence them are cutting speed, feed rate, cutting depth, inserts type and lubrication. The analysis of the result pointed out how was the influence of all factors on each response and also showed the efficiency and reliability of the method

An��lise da qualidade microbiol��gica em leite pasteurizado, tipo C, rec��m pasteurizado e na data de validade

The conservation of raw milk for long periods of time under refrigeration can result in the lost of its quality. This happens because bacterias, capable of developing in low temperatures, as psichrotrophics, in milk, associates with its enzymatic activities, are capable to degradate it. Although the pasteurization of milk sufficiently diminishes the transmission of the illnesses, that generally eliminates such microorganisms, is not a total efficient process because many enzymes produced for such bacterias are termostable, being able to resist the treatment and to remain active, leading to the loss of the quality of milk and its derivatives. The Normative Instruction 51 of 2002 established that milk must be cooled and stored in the production property, what resulted increasing the incidence of such bacteria in population destined milk. In some parts of the world contaminated milk is causing serious risks to the health of the population, assuming great importance in Public Health, mainly in relation to the hygienic-sanitary conditions of the product. ANVISA establishes, thus, maximum bacteriological concentration that must be evidenced before commercializing the product, guaranteeing the quality of milk as proper for consumption. Based on these aspects, the objective of this work is the microbiological analysis of 30 milk samples type C, collected in bakeries of the city Botucatu, in the state of S��o Paulo. Analysis were made to determinate the most likely number of termotolerants coliforms, as well the number of colony units of psichrotrophics bacterias, the presence of Salmonella and the enumeration of positive Staphylococcus aureus, at the moment of purchase and validity of the products

Avalia����o de momentos fletores em estruturas de funda����o tipo radier em concreto armado

It aims the comparison of these moments between an analytical plates theory and a computational numerical simulation. It is accented the details of studies about analytical theory as well the process, step by step, of a program that has as an influence the method of finite elements. The theory of plates has an extremely importance when it is talked about slabs and it takes as a base some fundamental hypotheses (that the middle point of the plate is considered flat and under formable) the points that are normal in relation to the middle surface is not considered because of its intensity that is irrelevant in comparison to the rest. The computational programs offer good results when they are applied in a correct way and, it resolves numerous functions in a short period of time. The objective is to highlight the importance of bending moments, its points of maximum and minimum, that has the objective of realize a good reinforcement sizing for a reinforced concrete. Furthermore, it can propitiate an economy in places that is demanded a small quantity of steel, before dimensioned for a load that is distributed in all the surface of the plate, at the same intensity

Revestimento interno de tubula����o por um processo de centrifuga����o utilizando resina ��ster-vin��lica com adi����o de cargas

Being the corrosion one of the great problems facing the industry today, specifically the internal corrosion of pipes in chemical and petrochemical industries, hence this work proposes a new type of internal coating in order to avoid fouling and decrease the pressure loss in the flow. For this, we use a composition of vinyl ester resins and manometric loads, which after cleaning and preparation of the internal surface of the tube will be applied through a process of centrifugation, adjusted by a lathe. After curing the resin, a test of roughness will be realized in order to analyze the reduction of friction factor and thus be able to conclude whether there was a significant decrease in pressure drop. With test results in hand, we hope to obtain a coating that meets most of the properties required by the industry and to provide a reduction in operating costs and a visible improvement in the conditions of use of the pipe

Modelagem de motor de combust��o internae simula����o do processo de queima de combust��vel

The internal combustion engine is a heat engine widely used in the automotive industry. In order to better understand its behavior many models in the literature have been proposed in the last years. The 0-D thermodynamic model is a fairly simple tool but it is very useful to understand the phenomenon of combustion inside the chamber of internal combustion engines. In the first phase of this work, an extensive literature review was made in order to get information about this kind of analysis and, after this, apply them in a model able to calculate the instantaneous temperature and pressure in one zone of the combustion chamber of a diesel engine. Therefore some considerations were made with the aim of increasing the accuracy of the model in predicting the correct behavior of the engine, adding the combined effects of heat transfer, leakage and injection. In the second phase, the goal was to study the internal flow of a three-dimensional model of an internal combustion engine. In order to achieve this goal the software Solidworks was used to create the geometries of an engine and the suite of softwares Ansys was used to create the moving mesh (ICEM CFD and CFX-Pre) and to solve the CFD problem (Ansys CFX code). The model was able to perform the air flow simulation during the four-stroke cycle of an engine: admission, compression, expansion and exhaust. The results obtained from both models were suitable and they open a new range of possibilities for future researches on the field

Processo de esmerilhamento, polimento e caracteriza����o de um Shear Plate

Shearplate is an optical glass plate having two flat surfaces and a small angle between them. The use of a high quality shear plate is essential to implement shear interferometric technique . The shear interferometry is a technique used to evaluate the light beam collimation. In order to guarantee the shearplate quality , the complete manufacturing process must be thoroughly monitored. In the manufacturing process, the first step consisted of the glass selection. The selected glass has been submitted to the process of cutting, gluing, chamfering, grinding and polishing. Each phase has been strictly monitored. The quality of the final result depends extremely on an appropriate starting condition, which arises from the grinding process, as the polishing process only recovers the brightness of the part, acting on a small scale on the wearing off of the part, as well as not changing the structured obtained in the grinding process. Respecting all stages of the manufacturing process, the quality of the part has evolved to a good result. The best result obtained showed PV distance of 162 nm, slightly less than �� / 4. This result is significant because the dimensions of the piece with respect to the dimensions of the polisher what interferes directly in the results. The closer are the dimensions of piece and the dimensions of the polisher, the greater the difficulty in controlling the propagation of errors

Estima����o do risco de morte de rec��m-nascidos utilizando logica fuzzy tipo-2 intervalar

The main objective of the presented study is the development of a predictive interval type-2 fuzzy inference system in order to estimate the mortality risk for a newborn, to be used as an auxiliary tool for decision making in medical centers where there is a lack of professionals for this purpose and, afterwards, to compare its performance to a type-1 fuzzy system. The input variables were chosen due to their acquisition ���simplicity, not involving any invasive tests, such as blood tests or other specific tests. The variables are easily obtained in the first few minutes of life: birth weight, gestational age at delivery, 5-minute Apgar score and previous report of stillbirth. Databases from the DATASUS were used to validate the model. 1351 records from the city of S��o Jos�� dos Campos, a mid-sized city in the S��o Paulo state���s countryside, were considered in this study. Finally, an analysis using the ROC curve was performed to estimate the model���s accuracy

Melhoria da qualidade de um processo de usinagem utilizando as t��cnicas de avalia����o de Taguchi

Delivering to the customers a product or service with the expected quality associated to the huge competitiveness that exists in the market nowadays, has been making organizations increasingly focus on quality planning using techniques which are directed towards the continuous improvement process and production optimization. Thus, this paper aims to improve a machining process using the techniques of experimental design to the optimization and this also includes the analysis of the measurement system. For this purpose, the alloy Nimonic 80A, a nickel base superalloy, was used in the process due to its widespread use for high temperatures, applying this study the robust method proposed by Genichi Taguchi, determining the influence of the factors considered input variables, cutting speed, feed rate, depth of cut, type of tool, lubrication, and material hardness, in the output or response variable, surface roughness, concluding with the use of Taguchi orthogonal array L16 and by analysis of ANOVA that the factor feed rate is significant and offers greater effect on the response variable studied, should be set to 0,12mm/rev. Moreover, the factor type of tool has more influence on the process when compared to other factors, being CP250 the one more suitable to the process. Lastly, the interaction feed rate x cutting speed provides greater significance in the process regarding to surface roughness variable, being the best match between them 0,12mm/rev to the feed rate and 90m/min to the cutting speed. In order to evaluate the measurement system, it was applied the repeatability and reproducibility method (R&R), through which we saw that the system needs improvement (R & R = 88.04% >>> 30%) as the value found in the study was well above compared to the one that classifies the system as inappropriate

Otimiza����o do processo de usinagem da superliga nimonic 80A utilizando o M��todo de Taguchi

Atualmente, atender as necessidades dos consumidores �� uma das metas mais importantes, os consumidores est��o em busca de produtos com qualidade e pre��os mais acess��veis, para isso, �� indispens��vel que as empresas se atualizem para melhorar seus produtos e servi��os. Com este cen��rio, as superligas est��o cada vez mais ganhando mercado, pois possuem ��timas propriedades, principalmente em rela����o a operar em temperaturas elevadas, podendo proporcionar maior efici��ncia para motores que necessitam trabalhar em altas temperaturas. Em contra partida a essa vantagem, as superligas possuem uma baixa usinabilidade, sendo importante a an��lise do processo de usinagem para se tornarem mais aplic��veis. Este trabalho visa �� otimiza����o do processo de torneamento cil��ndrico da superliga Nimonic 80A, com o intuito de melhorar a qualidade do produto, utilizando o M��todo de Taguchi, com o arranjo ortogonal L16, sendo o comprimento de corte definido como vari��vel resposta e analisados seis fatores que poderiam influenciar na sua varia����o, tais fatores s��o: velocidade de corte, avan��o, profundidade de corte, tipo de pastilha, lubrifica����o e dureza do material. Os resultados obtidos demonstraram que os fatores avan��o, tipo de pastilha e lubrifica����o s��o significativos e exercem influencia no processo, sendo que o avan��o deve ser ajustado no n��vel de 0,12 mm/rev, a pastilha a ser utilizada deve ser CP250 e a lubrifica����o deve ser feita de maneira abundante, para a otimiza����o do processo. Com a an��lise dos resultados, tamb��m podemos observar a efici��ncia e confiabilidade do m��todo utilizado, mostrando resultados coerentes

Ensino fundamental de nove anos: processo de implanta����o no mun��cipio de Rio Claro

The object of this study was to analyze the process of implementing the compulsory education to nine years, according to the Law 11.274/06, in Rio Claro. Thus it was established a brief analysis of the trajectory of Brazilian educational policy that began with the Law of Directives and Bases 4.024/61 and was followed by the Law 5.692/71, the 1988 Federal Constitution, the Law of Directives and Bases 9394 / 96, the National Educational Plan - Law 10.172/01, Law 11.114/05, 11.274/06 and the Constitutional Amendment. 59/2009, pointing to increase access to education that aims to expand and ensure free education and compulsory basic education for children aging from 04 to 17 years old. The research has been based on collecting bibliographical data, information and data for the municipality of Rio Claro, through official documents, semi-structured interviews, and research on government websites. The expansion of basic education to nine years has been securing the rights gained over time through education. Moreover, this expansion of education promotes a questioning about the quality of teaching and a concern for the financial contributions required for education.

A crian��a de 01 a 03 anos: uma reflex��o sobre a evolu����o da imita����o no processo de forma����o do eu

This investigation aims to observe play contents and elements that make it possible to notice if a child is at the imitation stage. First of all, this study reviews Piaget���s findings about the origins of imitation, and how it develops into representation. After that, ���game��� is analyzed in order to understand the cognitive representation and how children develop the ability to use symbols. Based on these assumptions, a study was developed into a public school (Prof�� Maria Teixeira Fittipaldi) with 9 children, aged between 1 to 3. Methodology included the observation of play and activity time; a diary to record the observations; and the analysis of the collected data, based on Piaget���s research into the classification and development of symbolic play. The results show that all observed situations were at the ���first stage���, which reveal the apogee of ludic symbolism, and that the kind of game varied according to the child���s age. Moreover, it was possible to notice the importance of symbolic play at preschool, since it triggers world knowledge development and helps interpersonal relationship growth.