• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 7
  • 5
  • Tagged with
  • 18
  • 18
  • 7
  • 5
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Temperature Variation Effects on Asynchronous PUF Design using FPGAs

Gujja, Swetha January 2014 (has links)
No description available.
12

Expressão imunoistoquímica de proteínas de choque térmico no tecido periodontal de ratos irradiados com laser de diodo / Immunohistochemical expression of heat shock proteins in rat periodontal tissues irradiated with Diodo Laser

Alves, Marco Aurélio Verlangieri 17 September 2009 (has links)
As proteínas de choque térmico (HSP) são expressas em todas as células humanas, sendo superexpressas em condições de estresse celular, tais como hiper ou hipotermia, isquemia, inflamação e reparação. Dentre as várias famílias de HSP, encontram-se a Hsp27 e a Hsp47, cuja superexpressão relaciona-se à inibição da apoptose e à manutenção dos filamentos de actina do citoesqueleto (Hsp27) e à manutenção do sistema de produção de procolágeno e do colágeno (Hsp47). O laser de diodo (LD) tem atualmente amplas aplicações clínicas com vantagens terapêuticas comprovadas, porém os efeitos térmicos que pode acarretar aos tecidos ainda são controversos. Neste trabalho, avaliou-se a influência do LD sobre a expressão imunoistoquímica das Hsp27 e Hsp47 sobre o tecido dentário submetido a gengivoplastia com LD e com bisturi convencional, bem como relacionou-se essa influência com as variações de temperatura provocadas pela irradiação laser. Vinte e quatro ratos adultos foram divididos em dois grupos: grupo 1 12 animais submetidos a gengivoplastia no incisivo central inferior esquerdo utilizando laser de diodo (ZAP soft lase, 810 nm, 0,3 W, densidade de energia de 113,63 J/cm2); grupo 2 12 animais submetidos a gengivoplastia no mesmo local utilizando bisturi convencional. Os animais sofreram eutanásia nos períodos de 0h, 24h, 72h e 120h, sendo os incisivos centrais retirados e descalcificados. Posteriormente foram submetidos a análise imunoistoquímica utilizando anticorpos monoclonais contra Hsp27 e Hsp47. Teste in vitro foi realizado utilizando-se incisivos centrais de ratos extirpados e mantidos resfriados até o momento do teste. Este foi realizado com a instalação de 4 termopares, os quais registraram a variação da temperatura durante gengivoplastia realizada com o LD calibrado com os mesmos parâmetros do teste in vivo. Observou-se haver variação máxima de temperatura entre 1C e 6C, dependendo da região analisada. A expressão da Hsp27 mostrou-se aumentada no grupo irradiado com laser em relação ao bisturi em praticamente todos os períodos experimentais. A Hsp47 também expressou-se mais intensivamente no grupo laser, porém mais tardiamente. A expressão de ambas as proteínas foi mais intensa na região irradiada, porém nas demais regiões medidas não foi possível relacionar as variações imunoistoquímicas com as de temperatura. Concluiu-se que o LD provoca modificações na expressão das Hsp27 e Hsp47, as quais podem estar relacionadas ao aumento da temperatura provocado pelo laser. / Heat shock proteins (HSP) are expressed in all human cells, and are overexpressed under conditions of cellular stress, such as hyper- or hypothermia, ischemia, inflammation and repair. Among the various families of HSP, there are Hsp27 and Hsp47, whose overexpression is related to the inhibition of apoptosis, maintenance of cytoskeletal actin filaments (Hsp27) and maintenance of the procollagen and collagen production system (Hsp47). At present, diode laser (DL) has broad clinical applications with proven therapeutic advantages; however, there is still controversy about the thermal effects it may have on tissues. In this study, the influence of DL on the immunohistochemical expression of Hsp27 and Hsp47 on dental tissue submitted to gingivoplasty with DL and a conventional scalpel was evaluated, as well as how this influence was related to the variations in temperature caused by laser irradiation. Twenty-four adult rats were divided into two groups: Group 1 12 animals submitted to gingivoplasty in the mandibular left central incisor using diode laser (ZAP soft lase, 810 nm, 0.3 W, energy density 113.63 J/cm2); Group 2 12 animals submitted to gingivoplasty in the same site using a conventional scalpel. The animals were euthanized in the periods of 0h, 24h, 72h and 120h, and the central incisors were removed and decalcified. Afterwards they were submitted to immunohistochemical analysis using monoclonal antibodies against Hsp27 and Hsp47. The in vitro test was performed, using the extirpated central incisors of rats, which were kept chilled until the time of the test. This was done by installing 4 thermocouples that recorded the variation in temperature during the gingivoplasty performed with DL calibrated with the same parameters as those of the in vivo test. It was observed that there was a maximum variation in temperature of between 1C and 6C, depending on the region analyzed. Hsp27 expression was shown to be increased in the laser-irradiated group when compared with the group treated by scalpel in practically all the experimental periods. Hsp47 was also more intensely expressed in the laser group, however, much later. The expression of both proteins was more intense in the irradiated region, but in the other regions measured, it was not possible to relate the immunohistochemical variations with those of temperature. It was concluded that DL causes changes in the expression of Hsp27 and Hsp47, which may be related to the temperature increase caused by laser.
13

Expressão imunoistoquímica de proteínas de choque térmico no tecido periodontal de ratos irradiados com laser de diodo / Immunohistochemical expression of heat shock proteins in rat periodontal tissues irradiated with Diodo Laser

Marco Aurélio Verlangieri Alves 17 September 2009 (has links)
As proteínas de choque térmico (HSP) são expressas em todas as células humanas, sendo superexpressas em condições de estresse celular, tais como hiper ou hipotermia, isquemia, inflamação e reparação. Dentre as várias famílias de HSP, encontram-se a Hsp27 e a Hsp47, cuja superexpressão relaciona-se à inibição da apoptose e à manutenção dos filamentos de actina do citoesqueleto (Hsp27) e à manutenção do sistema de produção de procolágeno e do colágeno (Hsp47). O laser de diodo (LD) tem atualmente amplas aplicações clínicas com vantagens terapêuticas comprovadas, porém os efeitos térmicos que pode acarretar aos tecidos ainda são controversos. Neste trabalho, avaliou-se a influência do LD sobre a expressão imunoistoquímica das Hsp27 e Hsp47 sobre o tecido dentário submetido a gengivoplastia com LD e com bisturi convencional, bem como relacionou-se essa influência com as variações de temperatura provocadas pela irradiação laser. Vinte e quatro ratos adultos foram divididos em dois grupos: grupo 1 12 animais submetidos a gengivoplastia no incisivo central inferior esquerdo utilizando laser de diodo (ZAP soft lase, 810 nm, 0,3 W, densidade de energia de 113,63 J/cm2); grupo 2 12 animais submetidos a gengivoplastia no mesmo local utilizando bisturi convencional. Os animais sofreram eutanásia nos períodos de 0h, 24h, 72h e 120h, sendo os incisivos centrais retirados e descalcificados. Posteriormente foram submetidos a análise imunoistoquímica utilizando anticorpos monoclonais contra Hsp27 e Hsp47. Teste in vitro foi realizado utilizando-se incisivos centrais de ratos extirpados e mantidos resfriados até o momento do teste. Este foi realizado com a instalação de 4 termopares, os quais registraram a variação da temperatura durante gengivoplastia realizada com o LD calibrado com os mesmos parâmetros do teste in vivo. Observou-se haver variação máxima de temperatura entre 1C e 6C, dependendo da região analisada. A expressão da Hsp27 mostrou-se aumentada no grupo irradiado com laser em relação ao bisturi em praticamente todos os períodos experimentais. A Hsp47 também expressou-se mais intensivamente no grupo laser, porém mais tardiamente. A expressão de ambas as proteínas foi mais intensa na região irradiada, porém nas demais regiões medidas não foi possível relacionar as variações imunoistoquímicas com as de temperatura. Concluiu-se que o LD provoca modificações na expressão das Hsp27 e Hsp47, as quais podem estar relacionadas ao aumento da temperatura provocado pelo laser. / Heat shock proteins (HSP) are expressed in all human cells, and are overexpressed under conditions of cellular stress, such as hyper- or hypothermia, ischemia, inflammation and repair. Among the various families of HSP, there are Hsp27 and Hsp47, whose overexpression is related to the inhibition of apoptosis, maintenance of cytoskeletal actin filaments (Hsp27) and maintenance of the procollagen and collagen production system (Hsp47). At present, diode laser (DL) has broad clinical applications with proven therapeutic advantages; however, there is still controversy about the thermal effects it may have on tissues. In this study, the influence of DL on the immunohistochemical expression of Hsp27 and Hsp47 on dental tissue submitted to gingivoplasty with DL and a conventional scalpel was evaluated, as well as how this influence was related to the variations in temperature caused by laser irradiation. Twenty-four adult rats were divided into two groups: Group 1 12 animals submitted to gingivoplasty in the mandibular left central incisor using diode laser (ZAP soft lase, 810 nm, 0.3 W, energy density 113.63 J/cm2); Group 2 12 animals submitted to gingivoplasty in the same site using a conventional scalpel. The animals were euthanized in the periods of 0h, 24h, 72h and 120h, and the central incisors were removed and decalcified. Afterwards they were submitted to immunohistochemical analysis using monoclonal antibodies against Hsp27 and Hsp47. The in vitro test was performed, using the extirpated central incisors of rats, which were kept chilled until the time of the test. This was done by installing 4 thermocouples that recorded the variation in temperature during the gingivoplasty performed with DL calibrated with the same parameters as those of the in vivo test. It was observed that there was a maximum variation in temperature of between 1C and 6C, depending on the region analyzed. Hsp27 expression was shown to be increased in the laser-irradiated group when compared with the group treated by scalpel in practically all the experimental periods. Hsp47 was also more intensely expressed in the laser group, however, much later. The expression of both proteins was more intense in the irradiated region, but in the other regions measured, it was not possible to relate the immunohistochemical variations with those of temperature. It was concluded that DL causes changes in the expression of Hsp27 and Hsp47, which may be related to the temperature increase caused by laser.
14

Efeito da atmosfera modificada e da variação de temperatura durante armazenagem na qualidade do figo "roxo de Valinhos" / Effect of modified atmosphere and temperature variation during storage in "roxo de Valinhos' " fig quality

Souza, Franciane Colares, 1979- 27 February 2007 (has links)
Orientador: Antonio Carlos de Oliveira Ferraz / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-11T01:53:24Z (GMT). No. of bitstreams: 1 Souza_FrancianeColares_M.pdf: 1587143 bytes, checksum: 6d3f8b92958d413b9d8e978f6b292226 (MD5) Previous issue date: 2007 / Resumo: A cultura do figo (Ficus carica L.) no estado de São Paulo iniciou-se no começo do século XX na região de Campinas e Valinhos, e desde 1990 vem ganhando destaque na região, responsável por 90% da produção nacional de figos de mesa, e tem conseguido espaço no mercado europeu no período de entressafra. O figo 'Roxo de Valinhos' é altamente perecível, com curta vida útil em condições ambientais, de 1 a 3 dias, razão pela qual deve ser comercializado rapidamente. Como não são aplicadas técnicas para conservação do figo, para que chegue em condição aceitável na Europa, a solução encontrada pelos produtores foi antecipar sua colheita, colhendo-o no estádio verde, bem mais cedo que o utilizado para o figo destinado ao mercado interno, prejudicando seu sabor e aparência. O objetivo deste trabalho foi avaliar o desempenho da atmosfera modificada ativa na qualidade e vida útil do figo 'Roxo de Valinhos¿. Utilizou-se o figo no estádio meio maduro (rami), armazenado com atmosfera modificada passiva (AMP) e atmosfera modificada ativa (AMA) com 20% de CO2 e 6,5% de O2, acondicionado em filme de polietileno de baixa densidade (PEBD) de 30µm, e armazenado durante uma semana sob quatro regimes térmicos (RT), com umidade relativa de 90±5%. Os RT avaliados foram temperatura constante de 20ºC±1ºC (RT1), temperatura constante de 10ºC±1ºC (RT2), temperatura de 20ºC±1ºC nas primeiras 48 horas de armazenamento seguida de um degrau negativo de 10ºC a partir o terceiro dia (RT3) e temperatura de 10ºC±1ºC no primeiro dia de armazenamento, seguidas por um degrau positivo de 10ºC no segundo dia, com diminuição para 10ºC do terceiro dia até o final do armazenamento (RT4). Para avaliação do desempenho das condições de atmosfera e regimes térmicos na qualidade do figo foram realizadas medidas de temperatura da polpa do figo, concentração gasosa nas embalagens (CO2, O2 e etileno), perda de massa, sólidos solúveis, acidez titulável, firmeza de polpa e aparência. As embalagens com AMA não mantiveram a concentração inicial de CO2 em 20%, devido à alta taxa de permeabilidade do filme a esse gás. A partir do quarto dia, a concentração de CO2 apresentou tendência de equilíbrio para os tratamentos com AMP e AMA, sem alterações significativas até o final do armazenamento. Os tratamentos com AMP e AMA mantiveram baixos índices de perda de massa, próximos a 1,5%, boa aparência e melhores índices de firmeza até o final do armazenamento, enquanto as frutas do tratamento testemunha não apresentaram condições de comercialização a partir do quarto dia. Foi evidenciado que o RT1 apresentou a pior condição para armazenamento do figo, favorecendo a perda de massa e ocorrência de podridão das frutas, e não foi observada diferença entre as frutas armazenadas com AMP e AMA / Abstract: The production fig (Ficus carica L.) began in the state of São Paulo at the beginning of XX century in the area of Campinas and Valinhos, and since 1990 this production is getting prominence as responsible for 90% of the national production of fresh figs, including exports to Europe. The ' Roxo of Valinhos' fig is highly perishable, lasting 1 to 3 days in room conditions, and therefore it shall be marketed quickly. Since conservation techniques are not usually applied in figs, the solution found by the producers for the product arrive in acceptable condition in Europe was to anticipate harvest, picking it in the green stadium, much earlier than used for the fig destined to the internal market, harming its flavor and appearance. The objective of this work was to evaluate the effect of an active modified atmosphere in quality and shelf life of the 'Roxo of Valinhos' fig. Figs were harvested at the middle stadium of ripening, stored with passive modified atmosphere and active modified atmosphere (20%CO2 and 6,5%O2), wrapped with low density 30µm polyethylene film (LDPE), and stored during one week under four thermal regimes (RT), with relative humidity of 90±5%. Thermal regimes (TR) used were constant temperature of 20ºC±1ºC (TR1), constant temperature of 10ºC±1ºC (TR2), temperature of 20ºC±1ºC in the first 48 hours of storage followed by a negative step of 10ºC in the third day (TR3) and temperature of 10ºC±1ºC in the first day of storage, followed for a positive step of 10ºC in the second day, with decrease for 10ºC of the third day to the end of the storage (TR4). For evaluation of the performance of the combination of atmosphere conditions and thermal regimes in the quality of the fig, there were performed measurements of pulp temperature, gaseous concentration in the packages (CO2, O2 and C2H4), weight loss, soluble solids, titritable acidity, pulp firmness and appearance. The packages with active modified atmosphere didn't maintain the initial concentration of CO2, due to the high diffusion rate of the film to that gas CO2 concentration achieved equilibrium at the fourth day for both of the treatments with passive and active modified atmosphere, without significant changes until the end of storage period. The treatments with modified atmosphere showed low indexes of weight loss, good appearance and little changes in firmness index till the end of storage, while the fruits of the control treatment didn't present marketable conditions at the fourth day. TR1 resulted in worst condition for storage of the fig, favoring weight loss and decay occurrence. No difference was observed among fruits stored with active and passive modified atmosphere / Mestrado / Tecnologia Pós-Colheita / Mestre em Engenharia Agrícola
15

Application of fluid inclusions in geological thermometry

Fall, Andras 22 January 2009 (has links)
Many geologic processes occur in association with hydrothermal fluids and some of these fluids are eventually trapped as fluid inclusions in minerals formed during the process. Fluid inclusions provide valuable information on the pressure, temperature and fluid composition (PTX) of the environment of formation, hence understanding PTX properties of the fluid inclusions is required. The most important step of a fluid inclusion study is the identification of Fluid Inclusion Assemblages (FIA) that represent the finest (shortest time duration) geologic event that can be constrained using fluid inclusions. Homogenization temperature data obtained from fluid inclusions is often used to reconstruct temperature history of a geologic event. The precision with which fluid inclusions constrain the temperatures of geologic events depends on the precision with which the temperature of a fluid inclusion assemblage can be determined. Synthetic fluid inclusions trapped in the one-fluid-phase field are formed at a known and relatively constant temperature. However, microthermometry of synthetic fluid inclusions often reveals Th variations of about ± 1- 4 degrees Centigrade, or one order of magnitude larger than the precision of the measurement for an individual inclusion. The same range in Th was observed in well-constrained natural FIAs where the inclusions are assumed to have been trapped at the same time. The observed small variations are the result of the effect of the fluid inclusion size on the bubble collapsing temperature. As inclusions are heated the vapor bubble is getting smaller until the pressure difference between the pressure of the vapor and the confining pressure reaches a critical value and the bubble collapses. It was observed that smaller inclusions reach critical bubble radius and critical pressure differences at lower temperatures than larger inclusions within the same FIA. Homogenization temperature (Th) variations depend on many factors that vary within different geological environments. In order to determine minimum and acceptable Th ranges fro FIAs formed in different environments we investigated several geologic environments including sedimentary, metamorphic, and magmatic hydrothermal environments. The observed minimum Th ranges range from 1-4 degrees Centigrade and acceptable Th range from 5-25 degrees Centigrade. The variations are mostly caused by the fluid inclusion size, natural temperature and pressure fluctuations during the formation of an FIA and reequilibration after trapping. Fluid inclusions containing H₂O-CO₂-NaCl are common in many geologic environments and knowing the salinity of these inclusions is important to interpret PVTX properties of the fluids. A technique that combines Raman spectroscopy and microthermometry of individual inclusions was developed to determine the salinity of these inclusions. In order to determine the salinity, the pressure and temperature within the inclusion must be known. The pressure within the inclusions is determined using the splitting in the Fermi diad of the Raman spectra of the CO₂ at the clathrate melting temperature. Applying the technique with to synthetic fluid inclusions with known salinity suggests that the technique is valid and useable to determine salinity of H₂O-CO₂-NaCl fluid inclusions with unknown salinity. / Ph. D.
16

Temperature Coefficients and Thermal Uniformity Mapping of PV Modules and Plants

January 2016 (has links)
abstract: The operating temperature of photovoltaic (PV) modules is affected by external factors such as irradiance, wind speed and ambient temperature as well as internal factors like material properties and design properties. These factors can make a difference in the operating temperatures between cells within a module and between modules within a plant. This is a three-part thesis. Part 1 investigates the behavior of temperature distribution of PV cells within a module through outdoor temperature monitoring under various operating conditions (Pmax, Voc and Isc) and examines deviation in the temperature coefficient values pertaining to this temperature variation. ANOVA, a statistical tool, was used to study the influence of various factors on temperature variation. This study also investigated the thermal non-uniformity affecting I-V parameters and performance of four different PV technologies (crystalline silicon, CdTe, CIGS, a-Si). Two new approaches (black-colored frame and aluminum tape on back-sheet) were implemented in addition to the two previously-used approaches (thermally insulating the frame, and frame and back sheet) to study temperature uniformity improvements within c-Si PV modules on a fixed latitude-tilt array. This thesis concludes that frame thermal insulation and black frame help reducing thermal gradients and next best viable option to improve temperature uniformity measurements is by using average of four thermocouples as per IEC 61853-2 standard. Part 2 analyzes the temperature data for two power plants (fixed-tilt and one-axis) to study the temperature variation across the cells in a module and across the modules in a power plant. The module placed in the center of one-axis power plant had higher temperature, whereas in fixed-tilt power plant, the module in north-west direction had higher temperatures. Higher average operating temperatures were observed in one-axis tracking as compared to the fixed-tilt PV power plant, thereby expected to lowering their lifetime. Part 3 focuses on determination of a thermal model coefficients, using parameters similar to Uc and Uv thermal loss factors used in PVsyst, for modules of four different PV technologies experiencing hot-desert climate conditions by statistically correlating a year-long monitored data. Thermal models help to effectively quantity factors influencing module temperatures to estimate performance and energy models. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2016
17

Influência da geometria de reatores UASB em escala unifamiliar sobre seu desempenho no tratamento de esgoto

Santos, Silvânia Lucas dos 16 December 2016 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2017-08-04T12:28:24Z No. of bitstreams: 1 PDF - Silvânia Lucas dos Santos.pdf: 42906938 bytes, checksum: 3a1f3a2d4994bd132f28a6d7ff2f02c8 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2017-08-29T15:43:57Z (GMT) No. of bitstreams: 1 PDF - Silvânia Lucas dos Santos.pdf: 42906938 bytes, checksum: 3a1f3a2d4994bd132f28a6d7ff2f02c8 (MD5) / Made available in DSpace on 2017-08-29T15:43:57Z (GMT). No. of bitstreams: 1 PDF - Silvânia Lucas dos Santos.pdf: 42906938 bytes, checksum: 3a1f3a2d4994bd132f28a6d7ff2f02c8 (MD5) Previous issue date: 2016-12-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this research a modified design of anaerobic UASB type reactors is proposed for sewage treatment at a single-family scale, with differentiated geometry. The robustness of these systems was investigated, when subjected to hydraulic loads similar to those usual in residences and the influence of temperature on anaerobic digestion. The experimental system consisted of 6 reactors UASB all with a useful volume of 240 L but having differentiated geometry: three had a diameter of 0.3 m in the digestion zone and three 0.4 m. Parallel to these systems a modified reactor with a lateral decanter (UASB-Y) and a conventional UASB reactor, also with 240 L, were operated. To assess the influence of temperature on anaerobic digestion, 4 UASB-Y reactors were used each with a volume of 25 L. The effect of temperature on the efficiency of the treatment was investigated for temperatures ranging from 25 to 12 ° C. The obtained results showed that, for the imposed operating conditions (mean hydraulic retention time of 12 and 6 hours), all the modified reactors presented COD removal efficiencies of more than 65%. Analysis of variance (ANOVA) confirmed that there was no significant difference in the removal efficiency for the different tested reactors, so that other criteria such as installation cost, operation and reactor height should be considered in the choice of treatment unit, according to the characteristics of the soil where they will be installed. The variations in flow peaks indicated that the modified reactors are robust and support a peak flow equivalent to 40% of the their treatment capacity, without great damage to the treatment system. The results showed that the efficiency of the treatment decreases with the temperature, mainly due to the inefficiency of the hydrolysis, when the reactors were temperatures below 25°C. In this way, it was concluded that the proposed UASB reactors, can effectively treat sewage from a family, in a unit of 240 L, reaching greater efficiency than reported for septic tanks systems, having good operational stability and recovery capacity, after application of hydraulic shocks similar to those produced in residences. / Nesta pesquisa é proposto um projeto modificado de reatores anaeróbios tipo UASB para o tratamento de esgoto em escala unifamiliar, concebido com geometria diferenciada. Foi investigada a robustez desses sistemas quando submetidos a variações de cargas hidráulicas similares às provocadas nas residências, além da influência da temperatura sobre a digestão anaeróbia. O sistema experimental constou de 6 reatores UASB todos com volume útil de 240 L tendo geometria diferenciada: três tinham diâmetro de 0,3 m na zona de digestão e três 0,4 m. Paralelamente aos sistemas modificados um reator com decantador lateral (UASB-Y) e um reator UASB convencional, também com 240 L, foram operados. Para avaliar a influência da temperatura sobre a digestão anaeróbia foram utilizados 4 reatores UASB-Y com volume de 25 L cada. O efeito da temperatura sobre a eficiência do tratamento anaeróbio foi investigado para temperaturas variando de 25 a 12°C. Os resultados obtidos mostraram que, para as condições operacionais impostas (TDH médio de 12 e 6 horas), todos os reatores modificados apresentaram eficiências na remoção de DQO decantada superior a 65%. A análise de variância (ANOVA) confirmou que não houve diferença significativa na eficiência de remoção para os diferentes reatores testados, de modo que outros critérios como custo de instalação, operação e altura do reator devem ser considerados na escolha da unidade de tratamento, de acordo com as características do local onde serão instalados. As variações de picos de vazão indicaram que os reatores modificados são robustos e suportam uma vazão de pico equivalente a 40% da sua capacidade de tratamento, sem grandes prejuízos ao sistema de tratamento. Os resultados mostraram que a eficiência do tratamento diminui com a diminuição da temperatura, provavelmente devido à ineficiência da hidrólise, quando os reatores foram operados com temperaturas inferiores a 25°C. Dessa forma, foi concluído, que os reatores UASB propostos, podem tratar de forma eficiente o esgoto de uma família, em uma unidade de 240 L, atingindo eficiência maior que a relatada para os tanques sépticos, tendo boa estabilidade operacional e capacidade de recuperação, após a aplicação de choques hidráulicos semelhantes aos produzidos nas residências.
18

[en] EFFECTS OF THE INTERNAL PRESSURE AND TEMPERATURE VARIATIONS ON SEISMIC RESPONSE SPECTRA OF TUBULAR SYSTEMS / [pt] A PRESSÃO INTERNA E A VARIAÇÃO DE TEMPERATURA NOS SISTEMAS DE TUBULAÇÃO E OS ESPECTROS DE RESPOSTA DE PROJETO PARA CARGAS SÍSMICAS

JAIR JOSE DOS SANTOS GOMES 11 July 2005 (has links)
[pt] A análise de estruturas de sistemas secundários sujeitos a cargas sísmicas é um assunto em aberto e especial no projeto de instalações industriais. Dois pontos particulares atraem a atenção dos especialistas no esforço a caminho de um projeto mais realista, abrangente e econômico: a interação das propriedades dinâmicas entre os sistemas principal e secundário e a quantidade de dutilidade do sistema secundário que pode ou deveria ser considerada no projeto. Está muito evidente nesse estágio que a decisão do projetista tem de ser bem assessorada porque dependendo das circunstâncias os resultados finais podem mostrar muitas surpresas. O contexto das experiências nesse assunto, na PUC-Rio, inclui uma série de iniciativas. Entre elas, se pode dar especial menção às seguintes: o estudo e proposta de uma metodologia para desenvolver um espectro de resposta acoplada (Valverde, 1998); o desenvolvimento de um modelo de sistema secundário simplificado: com vários graus de liberdade, linearelástico, formado por elementos tubulares, conexões e suportes com molas (Castañaga, 1998); a introdução do efeito inelástico nos elementos tubulares e suportes do sistema secundário simplificado e definição de um fator de dutilidade global do sistema para relacionar, qualitativa e quantitativamente, o espectro de resposta acoplada do sistema secundário simplificado, sob comportamento elástico e inelástico (Sampaio, 2003). Agora, um outro avanço é incorporado, com o presente estudo, o da influência de cargas estáticas nos elementos devidas à pressão interna e variação de temperatura, nessas relações do espectro de resposta elástica e inelástica. Também é feita uma comparação dos espectros de resposta elástica e inelástica do sistema secundário acoplado e não acoplado. Espectros médios aproximados para a resposta inelástica acoplada do sistema secundário simplificado são também propostos. / [en] The analysis of secondary structure systems to seismic loads is a special and open subject in the design of industrial installations. Two particular points attract specialist attention and effort on the way of a more realist, comprehensive and economical design: the dynamical properties interaction between the secondary and principal systems and the amount of the secondary system ductility which can or should be considered in the design. It is very clear at this stage that the designer decision has to be well advised because depending on circumstances the final results may show very surprising. The context of experiences on this subject, at PUC-Rio, includes a series of initiatives. Among them, one may to give special mention to the following: the study and proposal of a methodology to develop a coupled floor response spectrum (Valverde, 1998); the development of a simplified secondary system model: multidegree, linear-elastic, tubular elements and connexions and spring supports (Castañaga, 1998); the introduction of inelastic action in the tubular elements and supports of the simplified secondary system and the definition of a system overall ductility factor to relate, qualitative and quantitatively, the simplified secondary system coupled response spectrum under elastic and inelastic behavior (Sampaio, 2003). Now, another advancement is enhanced with this study on the influence of element static loads due to internal pressure and temperature variation on these elastic and inelastic response spectrum relationships. Comparison also is made into coupled and uncoupled secondary system elastic and inelastic response spectra. Approximated medium response spectra for the inelastic coupled response of a simplified secondary system are also proposed.

Page generated in 0.258 seconds