Orientador: Antonio Carlos de Oliveira Ferraz / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-21T00:09:48Z (GMT). No. of bitstreams: 1 Neves_GlendaAntoniadaRocha_M.pdf: 1917826 bytes, checksum: 2915458f369314d25d28ed53265c8fd6 (MD5) Previous issue date: 2012 / Resumo: A amêndoa de castanha do Brasil é apreciada internacionalmente por seu valor nutricional, no entanto, a desorganização do comércio, a falta de conhecimento adequado para manuseio do produto, investimentos e visão para perpetuação do negócio, durante décadas acarretaram a perda de mercado com consequente queda nas exportações. Desde os primeiros relatos encontrados sobre seu processamento, a castanha do Brasil é, de forma empírica, submetida a condicionamentos que visam o amolecimento da casca para facilitar sua quebra e obter amêndoas sem danos. O condicionamento mais aplicado atualmente no Brasil é o vapor sob pressão, no entanto a qualidade do produto final pode ser alterada, obtendo-se amêndoas com alto índice de acidez. A ausência de relatos técnicos científicos sobre o seu processamento nos motivou, neste trabalho, a investigar o efeito do condicionamento aplicado industrialmente na castanha do Brasil, e ainda investigar uma abordagem inovadora utilizando a radiação infravermelha como condicionamento para desidratação da casca. Para isto, foram realizadas avaliações com base no desempenho da decorticação, índice de acidez e resistência mecânica da amêndoa. Utilizou-se o delineamento composto central rotacional (DCCR) que permite visualizar a interação das variáveis associadas, que foram: vapor sob pressão combinado com tempo e aplicação de radiação infravermelha combinada com deformação específica; para este último condicionamento um secador de radiação infravermelha foi construído. Observou-se que os dois condicionamentos abordados afetaram na obtenção de amêndoas. No condicionamento com a maior pressão de 304 kPa durante 120 segundos obteve-se 17% de amêndoas liberadas e íntegras (IL), para esta mesma classe (IL) o condicionamento com aplicação do tempo médio de radiação infravermelha, durante 135s, e a menor deformação específica (4%), também foi de 17%. Nos ensaios com castanhas in natura não se obteve amêndoas sem danos mecânicos. O índice de acidez dos condicionamentos com vapor T2 (253 kPa e 100s); T6 (304 kPa e 120s); e T9 (203 kPa e 120s), já no inicio do período de armazenamento não estavam em conformidade com a legislação brasileira para óleos brutos, e após 45 dias todos as amostras estavam em desacordo com a legislação, exceto T7 (203 kPa e 90s) que teve o menor tempo de exposição ao vapor. Para o condicionamento com radiação infravermelha, apesar do lote utilizado não estar em conformidade com a legislação, após 45 dias de armazenamento houve pouca variação nos valores de acidez. Quanto à resistência mecânica da amêndoa, os tratamentos com vapor modificaram igualmente, já para o condicionamento com IV, apenas o maior tempo de exposição foi capaz de alterá-la. Os condicionamentos com vapor afetaram a qualidade da amêndoa, o contrário dos condicionamentos com radiação IV, e por isso, estes últimos merecem estudos futuros / Abstract: Brazil nut is appreciated internationally for its nutritional value, however the lack of organization of the productive chain, adequate knowledge about product handling, investments, and vision for the perpetuation of the business, resulted for decades in market loss with consequent decrease in exports. Since the first reports found about its processing, the Brazil nut is, empirically, subjected to heat conditioning that aims in softening the shell to facilitate its breaking and to obtain unruptured nuts. The most used conditioning in Brazil is the pressure associated with the superheated vapor, however the quality of the final product can be altered, obtaining nuts with a high degree of acidity. The lack of scientific reports about its processing motivated us, in this work, to investigate the effects of the conditioning applied industrially to the Brazil nut and investigate an innovative approach making use of infrared radiation as conditioning to dehydrate the shell. For this, assessments were made based on the performance of decortication, acidity index and mechanical resistance of the nut. The central composite designs (CCD) was used as it allows for the visualization of the interactions between the associated variable: superheated vapor, pressure combined with time and the use of infrared radiation combined with the specific deformation; for this last conditioning, an infrared radiation drier was designed and built. It was verified that both conditionings affected the obtainment of the nuts. In the conditioning with the highest pressure of 304 kPa during 120 seconds, it was observed that 17% of the nuts were liberated and intact (LI), for the same class (LI) the conditioning with application of the average time of infrared radiation, during 135s, and the smaller specific deformation, of 4%, was also 17%. The experiments with nuts in natura performed for each design did not obtain nuts without mechanical damages. The acidity index of the conditioning with vapor: T2 (253 kPa and 100s); T6 (304 kPa and 120s); and T9 (203 kPa and 120s), already in the beginning of the storage period were not in the range established by the Brazilian legislation for crude oils, and after 45 day all the samples were in violation of the legislation, except T7 (203 kPa and 90s) which had the least exposure to vapor. For the conditioning with infrared radiation, all the samples were in violation of the legislation with indexes above 4 mg KOH/g. The energy of deformation was used to assess the mechanical resistance of the nuts and, as expected, the energy was less in the vapor treatments, when compared to the nuts in natura and the inverse occurred for nuts subjected to infrared radiation / Mestrado / Tecnologia Pós-Colheita / Mestra em Engenharia Agrícola

Orientador: Antonio Carlos de Oliveira Ferraz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-04T17:41:19Z (GMT). No. of bitstreams: 1 Araujo_MaxCesarde_D.pdf: 7097825 bytes, checksum: 6b272d62beac51badea0f638230c5236 (MD5) Previous issue date: 2005 / Resumo: A agroindústria do caju tem como principal produto econômico à amêndoa da castanha e, atualmente, utiliza o impacto aleatório como princípio de decorticação, com perdas de 40 a 50% de amêndoas inteiras. O desenvolvimento de mecanismos mais adequados para a ruptura da casca e liberação de amêndoas inteiras, exige conhecimento e aplicação de parâmetros associados às propriedades mecânicas do material. Este trabalho investigou algumas destas propriedades da castanha 'CCP 76¿, tais como: variações nas dimensões características, massa e volume, microestrutura, fragilidade do endocarpo e rigidez da amêndoa. Investigou-se também, a deformação específica limite como parâmetro tecnológico para a abertura das castanhas, através de ensaios de impacto. Com os resultados obtidos nestes estudos, desenvolveu-se um protótipo decorticador de cilindros rotativos que utiliza o princípio da compressão combinado com um impacto direcionado. Utilizou-se a metodologia de superfície de resposta para avaliar os resultados dos ensaios mecânicos e de desempenho do protótipo proposto, com castanhas tratadas em diferentes níveis de umidificação e tratamento térmico. Os resultados obtidos evidenciaram alterações nas dimensões características, na massa e volume das castanhas, como também, na microestrutura do endocarpo. Os resultados do ensaio de cisalhamento do endocarpo e resistência da amêndoa apontaram diferenças entre material in natura e o tratado termicamente. Nos ensaios de impacto, obteve-se 77,55% de abertura das castanhas com liberação da amêndoa inteira utilizando-se a deformação específica limite de 19%, aplicada ao longo da largura. O protótipo decorticador proposto apresentou desempenho de 67,35% para ruptura total da casca e amêndoa inteira liberada, com apenas uma passada pelos cilindros, utilizando a rotação combinada de 1150-1750rpm. A preparação das castanhas através do efeito combinado do tempo de umidificação e tratamento térmico não afetou o desempenho do protótipo na faixa de variação utilizada, mas apontou a região de tendência onde às respostas são mais adequadas / Abstract: The cashew industry has as its main product the kernel of the cashew nut. Currently, it uses by large the random impact as decortication method which produces losses from 40 to 50% of whole kernels. The development of more appropriate mechanisms to rupture of shell and to release of whole kernel, demands knowledge and application of parameters associated with the mechanical properties of the nut. This work aimed to investigate some of these properties of cashew nut 'CCP 76', such as: variations in characteristic dimensions, mass and volume, microstructure, brittleness of the endocarp and rigidity of kernel associated with nut treatment prior to cracking. It was also investigated, the limit specific deformation as technological parameter using a specially designed impact tester. Based in those studies, it was designed and constructed a nut decorticator prototype with rotary cylinders to combine compression and impact to crack the shell. The response surface methodology was used to evaluate the results of the mechanical tests and the performance of the prototype when cashew nuts treated in different humidity levels and thermal treatment were used. The results showed changes in the characteristic dimensions, in the mass and volume of the cashew nuts as well as in the microstructure of the endocarp after heat treatment. The results for the shear tests in the endocarp and stiffness of the kernel pointed differences between in natura and thermally treated nuts. For the impact test, it was obtained 77,55% of free whole kernels using the limit specific deformation of 19%, applied along the width of the nut. The nut decorticator proposed was able to release 67,35% free whole kernel with just one pass between the cylinders, using the cylinders combined rotation of 1150-1750rpm. The combined effect of time of humidity and thermal treatment used in the preparation of the cashew nuts didn't seem to affect the performance of the prototype, in the range of used. However, it pointed out to an area in the response surface where the combination of treatments would be more appropriate / Doutorado / Maquinas Agricolas / Doutor em Engenharia Agrícola

In today's car industries, low investment costs and high production rates are sought. By using nut piercing in the stamping dies in the manufacture of body components, otherwise necessary subsequent tempos can be reduced. The goal of the work was to implement nut piercing from below in a reference die to be able to use this type of operation in future projects. The main problem when implementing nut piercing from below is to be able to handle and evacuate the scrap piece that remains after the punching. By studying the equipment in the reference die, a deeper understanding of the process could be obtained, at the same time as information and necessary material were collected by expertise and the case company's suppliers for nut piercing. The recommendation to the case company provides a solution proposal for scrap evacuation as well as the components involved to be able to carry out the operation.

Ancillary structures are highway support structures such as traffic signals, sign structures, luminaires, and high-mast light towers which are typically fastened to a concrete foundation using embedded anchor rods and anchor nuts. The inventory of ancillary structures across the United States is huge, and these structures vary dramatically in type, age, size, and material. There have been reported cases of anchor nut loosening on ancillary structures in the past few decades, but the cause of loosening is still unknown. Ancillary structures are susceptible to vibrations due to different wind loadings like natural gusts, vortex shedding, galloping, and truck-induced gusts. Wind-induced vibrations are believed to be one of the potential causes of anchor nut loosening. Previous research also suggests that vibrations can lead to loosening of nuts in structural and mechanical connections. There is concern regarding the current tightening procedures specified in the various federal and state specifications. Improper tightening can potentially lead to anchor nut loosening under the effect of wind-induced vibrations. In ancillary structures, the anchor rods and nuts are first snug-tightened using a wrench before fully pretensioning them as per the current specifications. The snug-tight condition is vaguely defined at present and needs revisions to avoid any under-tightening or over-tightening. Galvanization and overtapping of the anchor nuts also pose a potential concern. Anchor nuts are tapped oversize after galvanization to ensure the nuts fit well on the galvanized rod. American Society for Testing and Materials (ASTM) standards provide specific allowable tolerances on the thread parameters of the anchor rod and nut after galvanization and overtapping. Any deviation from the allowable tolerances can lead to gaps between the mating threads, which can contribute to the loosening of nuts under vibrations. This study focuses on investigating the following potential causes of loosening: improper tightening, wind-induced vibrations, snug-tight condition, and thread fabrication tolerance. Current tightening procedures for double-nut and single-nut connections on ancillary structures were verified using a tightening study as part of the investigation. New revisions to the specified nut rotation values for double-nut connections and a draft for proposed new specifications on single-nut connections has been provided as a result of discrepancies and inconsistencies in the current specifications. Vibration testing of a full-scale traffic signal was conducted on the basis of results from a four-month field monitoring program in order to investigate the effects of wind-induced vibrations on anchor nut loosening. It was concluded from testing that improper tightening (pretension < 5ksi) can lead to loosening of anchor nuts under wind-induced vibrations. A small-scale testing was also conducted to verify the results from the large-scale vibration testing. Snug-tight pretension in grade 55, 1-inch and 2-inch anchor rods was found to be highly variable due to different wrench lengths and personnel strength. Thread parameters of galvanized anchor rods and nuts procured from 3 different regional suppliers were found to be within specified tolerances. Various recommendations were then made as a result of the above tightening, vibration, and thread tolerance studies in an effort to reduce the cases related to anchor nut loosening in the future. / Doctor of Philosophy / Ancillary structures like traffic signals, sign structures, and light poles are typically connected to the ground using anchor rods and anchor nuts. There is a very large number of ancillary structures throughout the United States and vary in type, age, size, and material. There have been reported cases of anchor nut loosening on ancillary structures in the past few decades, but the cause of loosening is still unknown. Different types of wind loadings like natural gusts, vortex shedding, galloping, and truck-induced gusts vibrate the ancillary structures. These vibrations due to the wind are believed to be one of the potential causes of anchor nut loosening. Vibrations in the past have been shown to cause loosening of nuts in other structural and mechanical connections. There is also concern that the anchor rods and anchor nuts are not tightened properly as per the specifications, which can lead to loosening of nuts when the ancillary structures vibrate due to wind loadings. In ancillary structures, the anchor nuts are first made tight using a wrench with the full effort of a worker, also known as the snug-tight condition. The snug-tight condition is not properly defined at present and needs to be changed to prevent any under-tightening or over-tightening of the anchor nuts. Also, the anchor rods and nuts are generally coated with a hot zinc layer to prevent their corrosion when exposed to environmental effects like ice, snow, humidity, and rain. This process is called galvanization. The American Society for Testing and Materials (ASTM) provides some guidelines on the amount of coating allowed on the threads of the anchor rods and nuts. Any deviation from the allowable tolerances can lead to gaps between the threads of the anchor rod and nut, which can contribute to the loosening of nuts during vibrations of ancillary structures due to wind. This study focuses on investigating the following potential causes of loosening: improper tightening, vibrations of ancillary structures due to wind, snug-tight condition, and allowable tolerances for the amount of galvanization. Current tightening procedures for anchor rods and nut on ancillary structures were verified using a tightening study as part of the investigation. New revisions to the current tightening procedures have been provided as a result of discrepancies and inconsistencies observed in the current specifications. A traffic signal and a light pole were instrumented with sensors for four months to measure wind-related forces acting on these structures. Further, a full-scale traffic signal was vibrated in the laboratory using an electric motor to simulate the vibrations due to the measured wind forces. It was determined from the testing that if the anchor nuts were not properly tightened, they could become loose during vibrations due to wind. A small-scale testing was also conducted to check the results from the full-scale vibration testing. The snug-tight force in the anchor rods was also found to be dependent on the length of the wrench and the worker tightening it. The amount of galvanization on the rods and nuts procured from 3 different suppliers were found to be within allowable tolerances. Various recommendations were then made as a result of the conclusions in an effort to reduce the cases related to anchor nut loosening in the future.

The core of this thesis is the analysis of accelerating black hole solution with the NUT parameter, which was found by Chng, Mann and Stelea in 2006, and related spacetimes. The original work consists of three interconnected parts. In the first chapter we study the Taub-NUT solution, in particular the nature of its pathological axes, and we include a number of visualizations. In the second chapter we investigate the accelerating Taub-NUT solution, we present it in a new form, and we discuss its "deviation" from the Pleba'nski-Demia'nski class of solutions. To see the differences more clearly, in the final chapter we put also the Pleba'nski-Demia'nski metric into a completely new factorized form. The work is concluded by discussion of special subcases, from which it is clearly seen that the Pleba'nski-Demia'nski class does not contain the accelerating Taub-NUT solution.

Diploma thesis deals with a topic of lubrication and cooling of the ball screw rotary nuts. The first part is focused on a research behind the theory of ball screws and ball screw rotary-nuts. The three types of construction were developed in the second half of the thesis. Each construction is designed as an external attachable cooling and lubrication unit, which can be installed on an existing, slightly modified ball screw rotary-nut. For cooling and lubrication, only one type of medium is used and that is a cooled oil. External unit provides medium flow to ball screws working space. On top of diploma thesis tasks a design concept of ball screw rotary-nut with an integrated cooling and lubrication is introduced itself. Both described designs could become interesting for an industrial market.

Made available in DSpace on 2015-04-16T15:23:43Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5410765 bytes, checksum: 5281d9c890700ef5e1e636d911d5b44c (MD5) Previous issue date: 2013-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The general objective of this research is to (re)constitute the memory of the newspaper library at NUT-SECA, in the period of 1980-2012, as a support for future historiographies, and also, to contribute to the dissemination of information existing in the various thematic collections. It results from a descriptive research intending to build a history that emphasizes the diversity of content and the conditions of conservation, preservation and social use of the newspaper library as an artifact of information. The methodology has a quantitative-qualitative approach and uses documentary research to prepare the documents for data collection. For data analysis two techniques were applied: the Documentary Analysis (AD) and Content Analysis (CA). The results presents that the newspaper library collection at NUT- SECA is a historical documentation, as well as one of the memory locations of the drought and of Brazil s northeastern semi-arid, especially in Rio Grande do Norte, and that, depending on use, may contribute to the production of specific knowledge, strengthening the scientific literature on the theme of drought and general research in the field of Social Sciences. The final considerations are expected to have contributed to the construction of new knowledge about the newspaper library at NUT-SECA, as well as we hope the wide socialization of its collection to be a support for historiographies regarding this issue and/or on issues surrounding the NUT -SECA and its newspaper library / Re(constituir) a memória da Hemeroteca do NUT-SECA, no período de 1980 a 2012, como subsídios para futuras historiografias, e também, contribuir para a divulgação das informações existente nas diversas coleções temáticas configura-se como o objetivo geral da pesquisa. Resulta de uma pesquisa descritiva, com vista à construção de uma história que ressalte a diversidade do conteúdo e as condições de conservação, preservação e uso social da Hemeroteca enquanto artefato de informação. A metodologia parte de uma abordagem quantiqualitativa e utiliza a pesquisa documental para preparar os documentos à coleta de dados. Para a análise dos dados duas técnicas foram aplicadas: a Análise documental (AD) e a Análise de conteúdo (AC). Os resultados mostraram que a coleção hemerográfica do NUT-SECA é uma documentação histórica, assim como um dos lugares de memória da seca e do semiárido do nordeste brasileiro, particularmente do Rio Grande do Norte, e que, a depender do uso, pode contribuir para a produção de conhecimento específico, fortalecendo a produção científica acerca da temática da seca e das pesquisas de uma maneira geral no campo das Ciências Sociais. Nas considerações finais espera-se ter contribuído para a construção de novos conhecimentos a respeito da hemeroteca do NUT-SECA, assim como almeja a ampla socialização do acervo hemerográfico, como subsídio para historiografias referentes a essa temática e/ou sobre questões do entorno do NUT-SECA e sua hemeroteca

Made available in DSpace on 2014-12-17T15:01:57Z (GMT). No. of bitstreams: 1 MicheleSGD_tese.pdf: 2430121 bytes, checksum: 4479472ce6fc90295b8c785bc52f29fd (MD5) Previous issue date: 2005-10-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The chemical nature of the hidrocarbons found in gasoline directly affects the formation of oxidation complexes known as gums. Such complexes are slightly soluble in gasoline and their formation is delayed with the use of inhibitors, known as antioxidants. In this study, a synthetic compound (&#946;naphtol) and a natural subproduct (hydrogenated cardanol, derived from cashewnut shell liquid CNSL) have been used in order to generate novel antioxidant substances. These compounds were submitted to chemical reactions including alkylation, nitration and reduction, with the purpose of forming the following derivatives: 6(Nethyl,Nethylamino)&#946;naphtol (AO1); 6(Nethyl,Ndiethylamino)&#946;naphtol (AO2); amino&#946;naphtol (AO3); 2(Nethyl,Nethylamino)pentadecylphenol (AOC1), 2(Nethyl,Ndiethylamino)pentadecylphenol (AOC2) and aminopentadecylphenol (AOC3). The derivatives were subjected to accelerated oxidative stability assays (Potential Gum and Induction Period) and to storage assays (Washed Gum and ASTM Color) during six months, with naphtha provided by the petroleum refinery RPBC (Refinaria Presidente Bernardes de Cubat?o, in Brazil). The results for the derivatives were compared to those for commercial additives [DBPC (2,6ditbutyl4methylpcresol) and PDA (N,N disecbutylpphenylenediamine)], which were also added to the naphtha produced at RPBC at the moment of sampling. From all tested antioxidants, the novel antioxidant AOC1 (derived from hydrogenated cardanol) yielded a better global performance. During the period of time in which the naphtha was stored, an examination of this material was carried out in parallel, using the mass spectrometry technique. This study allowed to monitor the formation of a triolefinic compound, as well as the observation of subsequent formation and rupture of the olefinic constituents. As an eventual result from these experimental investigations, a reaction route leading to gum formation has been suggested / O tipo de hidrocarboneto presente na gasolina influencia diretamente na forma??o de complexos de oxida??o conhecidos como goma. Estes complexos s?o levemente sol?veis em gasolinas e sua forma??o ? retardada atrav?s de uso de inibidor, conhecido como antioxidante. Neste estudo utilizouse um composto de origem sint?tica (&#946;naftol) e um subproduto natural (cardanol hidrogenado (derivado do l?quido da castanha de caju (LCC)) para obten??o de novas subst?ncias antioxidantes. Os compostos citados foram submetidos a rea??es qu?micas de alquila??o, nitra??o e redu??o para obten??o dos seguintes derivados : 6(Netil,Netilamino)&#946;naftol (AO1), 6(Netil,Ndietilamino)&#946;naftol (AO2), Amino&#946;naftol (AO3), 2(Netil,Netilamino)pentadecilfenol (AOC1), 2(Netil,Ndietilamino)pentadecilfenol (AOC2) e Aminopentadecilfenol (AOC3). Os novos derivados foram submetidos a ensaios acelerados de estabilidade oxidativa (Goma Potencial e Per?odo de Indu??o) e a testes de estocagem (Goma Lavada e Cor ASTM) durante seis meses com nafta amostrada na RPBC (Refinaria Presidente Bernardes de Cubat?o). Os resultados com os novos derivados foram comparados ?queles obtidos com aditivos comerciais [DBPC (2,6diterbutil (4 metil)pcresol) e PDA (N,N disecbutilpfenilenodiamina)]que tamb?m foram adicionados ?s naftas da RPBC no momento da amostragem. O novo antioxidante AOC1(derivado do cardanol hidrogenado) apresentou melhor desempenho global dentre todos os antioxidantes amostrados. Durante o per?odo em que as naftas amostradas foram estocadas, foi realizado, em paralelo, um acompanhamento deste material atrav?s da t?cnica de Espectrometria de Massas e registrouse, n?o somente, a forma??o de um composto triolef?nico, como tamb?m acompanhouse as forma??es e as rupturas, subseq?entes, de compostos olef?nicos. Este acompanhamento possibilitou a sugest?o de uma rota reacional que leva ? forma??o de goma

This thesis solves the problem of design and production of a special mounting device for the impeller nut of the main circulation pump GCN-317. The proposed device is intended to solve the problems associated with the mounting and dismounting of this nut. The work provides basic information about the Dukovany Nuclear Power Plant and VVER-440 systems in general, including their brief history. It also introduces the operational and legislative environment of the primary circuit of the nuclear power plant. It deals with the task and technical description of the main circulation pump and its overhaul. The following sections present the basic principles of construction of the device and an overview of its components with a description of their purpose and method of production. The last part of the thesis describes the function of the device and its verification and reports on its deployment.

This thesis deals with construction of rotary-nut ball screw. In the first chapter technical research at the current state of linear positioning systems and matters associated with them is listed. The next chapter treats of basic concepts and designs referring to ball screws. Further on the boundary between rotary ball screw and rotary- nut ball screw is described. On basis of restrictions and selected criterions solution of one size of rotary – nut ball screw with all the calculations.