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Escoamento multifásico não-isotérmico em riser flexível: modelagem e simulação. / Non-isothermal multiphase flow in flexible riser: modeling and simulation.NASCIMENTO, Genildo Ribeiro do. 05 November 2018 (has links)
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Previous issue date: 2011-08-24 / Este trabalho apresenta um estudo teórico sobre escoamento multifásico (gás-óleo pesado-água) em dutos flexíveis que tem uso em diversas aplicações da indústria petrolífera e não petrolífera. As equações governantes são baseadas no modelo multifluido Euleriano-Euleriano não-homogêneo, considerando o escoamento tridimensional em regime permanente laminar e não-isotérmico. As simulações foram efetuadas usando-se o código computacional CFX-3D. Os resultados das distribuições de velocidade, pressão, fração volumétrica e temperatura ao longo do duto são apresentadas e analisadas. Verificou-se que a curvatura do duto e a fração volumétrica das fases presentes têm forte influência na hidrodinâmica do escoamento. Fez-se uma avaliação da região onde pode ocorrer precipitação de parafina e os resultados obtidos são consistentes fisicamente e permitem um melhor conhecimento acerca do escoamento multifásico (água, óleo pesado e gás). / This work presents a theoretical study on multiphase flow (gas-heavy oil-water) in flexible
pipe which is used in many applications of petroleum industry and others industries. The
governing equations are based on Eulerian-Eulerian multifluid model and non-omogeneous, by considering the steady non-isothermal laminar flow. The simulations were performed using the computer code CFX-3D. Results of the velocity, pressure, volume fraction and temperature distributions along the pipeline are presented and analyzed. It was verified that the curvature of the pipe and the volumetric fraction of the phases has large influence in the hydrodynamic of flow. An evaluation of paraffin precipitation and the results are consistent physically and allow a better knowledge of multiphase flow (water, heavy oil, gas).
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Detecção de parafina por instrumentação ultrassônica / Detection of Paraffin by Ultrasonic InstrumentationNabeyama, Guilherme Natsutaro Descrovi 26 November 2015 (has links)
Agência Nacional de Petróleo; FINEP / A obstrução das paredes internas de tubulações de transporte e produção de petróleo devido à sedimentação de hidrocarbonetos é um problema grave que pode acarretar riscos operacionais, perdas de equipamentos e gerar prejuízos à indústria. Este trabalho tem por objetivo realizar experimentos utilizando ultrassom, na caracterização de depósitos de parafina em superfícies metálicas, com enfoque na estimativa da espessura desses acúmulos. Os testes foram realizados em uma bancada experimental onde corpos de prova com diferentes espessuras de aço e depósitos de parafina foram mensurados. Os resultados experimentais mostraram que devido à diferença entre as propriedades acústicas do aço e da parafina a utilização de ultrassom, para detectar a presença de depósitos de parafina, torna-se uma tarefa bastante complexa. A medição com exatidão será dependente do meio que fará interface com a parafina, o qual deverá ter certas características para um casamento de impedância acústica com o depósito, permitindo uma maior reflexão do sinal. A técnica de supressão de ecos utilizada para detecção dos depósitos mostrou-se bastante satisfatória, fornecendo uma resposta final com incerteza inferior a 0,32mm. / An obstruction in the oil pipelines’ inner walls of transport and production due to hydrocarbon deposition is a serious problem that can cause operational risks, equipment losses and lead to losses to the industry. This work aims to conduct experiments using ultrasonic waves, to detect paraffin deposits on steel surfaces, focusing in the estimation of the thickness of these accumulations. The tests were conducted in a test rig where specimens with different thicknesses of steel and paraffin deposits were measured. The experimental results showed that due to the difference between the acoustic properties of the steel and paraffin the use of ultrasound, for detecting paraffin deposits, becomes a very complex task. Measuring accurately is dependent on the medium that will interface with the wax, which must have certain characteristics for the acoustic impedance coupling with the deposit, allowing a greater reflection of the ultrasound signal. The echo suppression technique used to detect the deposits proved to be quite satisfactory, providing a response value with uncertainty of less than 0.32mm.
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Detecção de parafina por instrumentação ultrassônica / Detection of Paraffin by Ultrasonic InstrumentationNabeyama, Guilherme Natsutaro Descrovi 26 November 2015 (has links)
Agência Nacional de Petróleo; FINEP / A obstrução das paredes internas de tubulações de transporte e produção de petróleo devido à sedimentação de hidrocarbonetos é um problema grave que pode acarretar riscos operacionais, perdas de equipamentos e gerar prejuízos à indústria. Este trabalho tem por objetivo realizar experimentos utilizando ultrassom, na caracterização de depósitos de parafina em superfícies metálicas, com enfoque na estimativa da espessura desses acúmulos. Os testes foram realizados em uma bancada experimental onde corpos de prova com diferentes espessuras de aço e depósitos de parafina foram mensurados. Os resultados experimentais mostraram que devido à diferença entre as propriedades acústicas do aço e da parafina a utilização de ultrassom, para detectar a presença de depósitos de parafina, torna-se uma tarefa bastante complexa. A medição com exatidão será dependente do meio que fará interface com a parafina, o qual deverá ter certas características para um casamento de impedância acústica com o depósito, permitindo uma maior reflexão do sinal. A técnica de supressão de ecos utilizada para detecção dos depósitos mostrou-se bastante satisfatória, fornecendo uma resposta final com incerteza inferior a 0,32mm. / An obstruction in the oil pipelines’ inner walls of transport and production due to hydrocarbon deposition is a serious problem that can cause operational risks, equipment losses and lead to losses to the industry. This work aims to conduct experiments using ultrasonic waves, to detect paraffin deposits on steel surfaces, focusing in the estimation of the thickness of these accumulations. The tests were conducted in a test rig where specimens with different thicknesses of steel and paraffin deposits were measured. The experimental results showed that due to the difference between the acoustic properties of the steel and paraffin the use of ultrasound, for detecting paraffin deposits, becomes a very complex task. Measuring accurately is dependent on the medium that will interface with the wax, which must have certain characteristics for the acoustic impedance coupling with the deposit, allowing a greater reflection of the ultrasound signal. The echo suppression technique used to detect the deposits proved to be quite satisfactory, providing a response value with uncertainty of less than 0.32mm.
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Padronização de uma Reação em Cadeia pela Polimerase (PCR) para detecção do herpesvírus equino tipo 1 em tecidos incluídos em parafina / Standardization of a Polymerase Chain Reaction (PCR) for Equine Herpesvirus type 1 detection in Paraffin-Embeded TissuesCamila Oliveira do Prado 26 September 2011 (has links)
O Herpesvírus equino tipo -1 (EHV-1) pertence ao gênero Varicellovírus da subfamília Alphaherpesvirinae pertencente à Família Herpesviridae. É um vírus envelopado, de DNA linear fita dupla, composto por 76 genes distintos. O EHV-1 é responsável por grandes prejuízos econômicos na equinocultura mundial. Responsável por doença neonatal fatal, mieloencefalopatia, rinopneumonite e abortamento, encontra-se amplamente distribuído pela população equina do território nacional. O objetivo do presente estudo foi o de padronizar uma reação em cadeia pela polimerase (PCR) para detecção do EHV-1 em tecidos incluídos em parafina a fim de permitir estudos retrospectivos em arquivos de amostras histopatológicas. Assim, foram inoculados experimentalmente 12 camundongos com 21 dias de idade da linhagem CH3/Rockfeller com três diferentes isolados de EHV-1, dois provenientes da Argentina e um do Brasil. Esses animais foram observados por quatro dias e, após sacrifício por sobre dose de uma associação de ketamina e xilazina, foram submetidos à necropsia e colhidos o pulmão e sistema nervoso central (SNC). Os órgãos colhidos foram divididos em duas partes aproximadamente iguais: uma mantida a -20ºC até processamento e a outra fixada em formalina 10% tamponada e posteriormente incluída em parafina. A extração foi realizada com nove fragmentos contínuos de 4µm cada, a partir do protocolo de extração com proteinase K/ fenol/ clorofórmio. Foi realizada avaliação da sensibilidade analítica da PCR com oito diluições na base 10 para os três isolados utilizados. A amplificação do DNA viral foi realizada utilizando primers direcionados para a ORF64. A fim de descartar a eventual presença de inibidores da reação de PCR e assegurar a adequada extração de DNA, foram incluídos primers direcionados para o gene da beta-actina. A PCR mostrou-se capaz de amplificar DNA viral alvo numa diluição de até 10-5, sendo positiva entre 10-1 a 10-2 DICT50/25µL. Com a PCR padronizada, foi possível detectar o DNA do EHV-1 em: a) 100% (12/12) das amostras de pulmão congeladas e 100% (12/12) das amostras de pulmão incluídas em parafina; b) em 91% (11/12) das amostras de SNC congeladas e 41% (5/12) das amostras de SNC incluídas em parafina. A aplicação da PCR padronizada em uma coleção de amostras incluídas em parafina do Laboratório de Anatomia Patológica do IB/SP, colhidas de cinco casos de abortamento em equinos, revelou que o DNA do EHV-1 foi detectado em: a) um caso em que originalmente foi possível isolar o EHV-1; b) em 4/4 amostras que revelaram-se originalmente negativas. Com base nos resultados obtidos, foi possível concluir que a PCR padronizada teve bom desempenho na detecção de DNA viral em amostras incluídas em parafina de animais experimentalmente infectados e, provavelmente, uma sensibilidade diagnóstica mais elevada que os métodos utilizados para o diagnóstico do EHV-1 na coleção de amostras de equino testada. / The equine herpesvirus type 1 (EHV-1) belongs to Varicellovírus genus, Alphaherpesvirinae subfamíly of the Herpesviridae Famíly. It is an enveloped virus, double stranded linear DNA, composed of 76 distinct genes. The EHV-1 is responsible for great losses in horsebread world. Responsible for neonatal death, mieloencephalopaty, rinopneumonite and abortion, it is widely distributed into brasilian equine population. The purpose of this study was to standardize a polymerase chain reaction (PCR) for EHV-1detection in paraffin- embedded tissues allowing retrospective studies based on the collection histopatological samples. Thus, 12 mice (CH3/Rockfeller) with 21 days of age were inoculated with 3 different isolates of EHV-1, 2 from Argentina and one from Brazil. These mice were observed for 4 days and, after sacrifice by overdose of a combination of ketamine and xylazina, it were subjected to necropsy and collected the lung and central nervous system (SNC). The collected tissues were divided into 2 approximately equal parts: 1one stored at -20ºC until processing, and another set at 10% buffering formalin and later paraffin-embedded. The extraction was performed with continuous 9 fragments of 4µm each, using the extration protocol with proteinase K/ fenol/ clorofórmio. The assessment of analytical sensitivity of PCR were determined using 8 dilutions for all 3 virus isolates. The viral DNA amplification was performed using primers targeted to ORF64. In order to rule out the possible presence of PCR inhibitors and to ensure adequate extraction of DNA, primers directed to the gene for beta-actin were included It was possible to amplify viral DNA until 10-5 dilution, corresponding to 10-1 to 10-2 DICT50/25µL. With the standardized PCR, it was possible to detect the EHV-1 DNA in: a) 100% (12/12) of lung frozen sample and 100% (12/12) of the paraffin-embedded lung; b) 91% (11/12) of the frozen CNS and 41% (5/12) CNS paraffin-embedded. Moreover, the standardized PCR was tested in a collection of paraffin-embedded specimens from Pathological Anatomy Laboratory od Biological Institute Sao Paulo State, taken 5 cases of the abortion in horses. It were possible to detect EHV-1 DNA in: a) 1 sample from a case in that originally was possible to isolate the EHV-1, b) 4/4 sample originally negative diagnosed. Based on these results, it is possible to conclude that the standardized PCR performed well for detection viral DNA in paraffin-embedded tissues of experimentally infected animals, and probably a higher diagnostic sensitivity than the methods used for diagnosis of EHV-1 in the collection samples tissues tested for equine.
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"Avaliação crítica do uso da reação em cadeia da polimerase e exames complementares no diagnóstico da tuberculose cutânea e micobacteriose atípica" / The role of polymerase chain reaction and panel exams in the diagnosis of cutaneous tuberculosis and atypical mycobacteria skin infection compared to clinical evaluationCristina Martinez Zugaib Abdalla 30 November 2005 (has links)
Realizou-se estudo comparando o uso da reação em cadeia da polimerase à evolução clínica e painel de exames tradicionais para diagnóstico em pacientes com suspeita clínica de tuberculose cutânea e micobacteriose atípica. Observou-se sensibilidade da reação em cadeia da polimerase de 88%, especificidade de 83%, valor preditivo positivo de 82%, valor preditivo negativo de 88% e acurácia de 85% com concordância pelo teste de McNemar (p= 0,655). Os exames do painel de maior acurácia, após a reação em cadeia da polimerase, foram o teste tuberculínico com acurácia de 79% e a presença de dermatite crônica granulomatosa com reação em cadeia da polimerase positiva com acurácia também de 79%, ambos com concordância pelo teste de McNemar (p= 0,179 e p= 0,655, respectivamente) / A study was performed comparing the polymerase chain reaction and the traditional panel of exams for the diagnosis in patients with a clinical suspicion of cutaneous tuberculosis and atypical mycobacteria infection to the clinical evaluation. It was observed that the sensitivity of the PCR was 88%, the specificity was 83%, the positive predictive value was 82%, the negative predictive value was 88% and the accuracy was 85% in agreement with the McNemar test (p=0.655). The panel exams of second highest accuracy, were the tuberculin test with an accuracy of 79% and the chronic granulomatous dermatitis with positive PCR, also with an accuracy of 79%, both in agreement with the McNemar test (p=0.179 and p=0.655, respectively)
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Auto-Ignition of Liquid n-Paraffin Fuels Mixtures as Single Droplets Using Continuous ThermodynamicsSabourin, Shaun January 2011 (has links)
This thesis reports a model to predict the auto-ignition time of single droplets of n-paraffin fuel mixtures using the method of continuous thermodynamics. The model uses experimental data for pure fuels to fit rate parameters for a single-step global chemical reaction equation; from this, correlations for rate parameters as a function of species molecular mass are derived, which are integrated to produce a continuous thermodynamics expression for mixture reaction rate. Experiments were carried out using the suspended droplet-moving furnace technique. The model was then tested and compared to experimental data for three continuous mixtures with known compositions: one ranging from ¬n-octane to n-hexadecane, the second ranging from n-dodecane to n-eicosane, and the third being a combination of the first two mixtures to produce a “dumbbell” mixture. Discrete and continuous mixture models of the ASTM standard distillation test were compared to design the experimental mixtures and provide the distribution parameters of the continuous mixtures intended to simulate them. The results of calculations were found to agree very well with measured ignition times for the mixtures.
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Increasing Effective Thermal Resistance of Building Envelope's Insulation Using Polyurethane Foam Incorporated with Phase Change MaterialHoul, Yassine 05 1900 (has links)
Incorporating insulation material with phase change materials (PCMs) could help enhance the insulation capability for further building energy savings by reducing the HVAC loadings. During the phase change process between the solid and liquid states, heat is being absorbed or released by PCMs depending on the surrounding temperature. This research explores the benefits of a polyurethane (PU)-PCM composite insulation material through infiltrating paraffin wax as PCM into PU open cell foam. The new PU-PCM composite provides extra shielding from the exterior hot temperatures for buildings. Through this study, it was demonstrated that PU-PCM composite insulation could potentially help building energy savings through reducing the loads on the HVAC systems based on the building energy modeling using EnergyPlus. The Zero Energy Lab (ZØE) at the University of North Texas was modeled and studied in the EnergyPlus. It is a detached building with all wall facades exposed to the ambient. It was determined that the new PU-PCM insulation material could provide 14% total energy saving per year and reduce the electricity use due to cooling only by around 30%.
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Oxidative dyhydrogenation of propane and butane to olefins using Co(5)MgA/O catalystMajoe, Nampe 04 1900 (has links)
Olefins have enjoyed many uses in a wide variety of industries, from car manufacturing to energy production. Energy consuming processes of catalytic dehydrogenation, turning paraffins into olefins, has been commercialised since the early 20th century, while catalytic oxydehydrogenation of paraffins to olefins is still in prototype stages. The conflict between kinetic and thermodynamic yield constraints, has delayed the commercialisation of this process. The solution to achieving the relevant process route is exploitation of the right catalyst at moderate temperatures and pressures. Co5MgAlO is studied under atmospheric pressure and 350°C temperature, to dehydrogenate propane and butane to olefins using oxygen as a reactant. Thermodynamic models showing how many reaction routes are possible under atmospheric pressure were explored. Experimental results for butane to air at ratio of 1:0.8 and 1:1.2 hydrocarbons to air gave better selectivity of 1-butene which was more than 12%. When compared with propane at similar reaction ratios the reaction favoured CO2 at selectivity of more than 95%. / Civil and Chemical Engineering / M.Tech. (Chemical Engineering)
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Thermal Transport Properties Enhancement of Phase Change Material by Using Boron Nitride Nanomaterials for Efficient Thermal ManagementBarhemmati Rajab, Nastaran 12 1900 (has links)
In this research thermal properties enhancement of phase change material (PCM) using boron nitride nanomaterials such as nanoparticles and nanotubes is studied through experimental measurements, finite element method (FEM) through COMSOL 5.3 package and molecular dynamics simulations via equilibrium molecular dynamics simulation (EMD) with the Materials and Process Simulations (MAPS 4.3). This study includes two sections: thermal properties enhancement of inorganic salt hydrate (CaCl2∙6H2O) as the phase change material by mixing boron nitride nanoparticles (BNNPs), and thermal properties enhancement of organic phase change material (paraffin wax) as the phase change material via encapsulation into boron nitride nanotubes (BNNTs). The results of the proposed research will contribute to enhance the thermal transport properties of inorganic and organic phase change material applying nanotechnology for increasing energy efficiency of systems including electronic devices, vehicles in cold areas to overcome the cold start problem, thermal interface materials for efficient heat conduction and spacecraft in planetary missions for efficient thermal managements.
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FABRICATION OF SOLVENT AND TEMPERATURE SENSITIVEPOLYMER BILAYER BENDING ACTUATORSJian, Pei-Zhen 10 September 2019 (has links)
No description available.
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