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Dewell, Elizabeth A. (Elizabeth Anderson) 1980. "Tilt bed testing of the subjective horizontal." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/69235.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2002.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (leaf 25).
Mittelstaedt (1987) suggested that inversion illusions which caused space sickness in astronauts was associated with a net headward bias in the body's gravireceptor organs, which could be measured on Earth using a tilting bed. Mittelstaedt showed that when individual subjects were asked to repeatedly position themselves to the gravireceptive subjective horizontal, individuals showed a small (<5 deg.) but consistent head up or head down bias that remained stable when retested weeks, months or even years later. A correlation with inversion illusion was noted in a small number of astronauts. The purpose of the present project was 1) to construct a new bed of slightly different design and 2) to verify Mittelstaedt's findings using a different subject population. Nine subjects each lay on their left side with their head immbobilized using a bite bar. They positioned the bed (and themselves) at the subjective horizontal ten successive times starting from standardized initial tilt angles which ranged from +/- 10 degrees. Tests were then repeated on right side. Four subjects returned a day later for retesting. Results showed that subjects repeatedly positioned themselves at their own subjective gravitational horizontal, which differed from true horizontal by several degrees a head down direction. Results of tests on the left and right side had similar means for most of the nine subjects; however 4 were statistically different. Left and right sides were combined, noting the above error. Mean biases in the subjective horizontal varied from -3.26 to -0.82 degrees head down between subjects, with overall mean -1.65 and s.d. 0.80. There was a statistically significant difference between responses of some subjects. Data from four subjects tested on both days was compared. A statistically significant correlation was not found, perhaps due to the small subject retest population. The differences between Mittelstaedt's data and present results are discussed.
by Elizabeth A. Dewell.
S.B.
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Rosenthal, G. N. "Lift forces on spherical particles near a horizontal bed in oscillatory flow." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377239.
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Li, Fang. "Heat Transfer in a High-pressure Gas-solid Fluidized Bed with Horizontal Tube Bundle and Continuous Addition of Fines." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38002.
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Climate change is becoming more severe than ever in human history and the emission of green house gas urgently needs to be reduced while global energy consumption remains booming. Large-scale application of clean fossil fuel combustion shall be considered as a priority for its economical advantages as well as reliability in meeting global energy needs. Oxygen-fired pressurized fluidized bed combustor technology with downstream carbon capture and sequestration is considered a key approach to clean coal combustion. In such technology, the fluidized bed combustor operates at elevated pressures and houses an in-bed heat exchanger tube bundle. It is essential to understand the rate of heat transfer between the immersed heat exchange surface and the fluidized bed as it is a key parameter in heat exchanger design. The goal of this work was to investigate the impact of pressure and presence of fine particles (i.e., surrogate for pulverized fuel) on the overall tube-to-bed heat transfer coefficient.
Experiments were conducted in a pilot-scale fluidized bed with an inner diameter of 0.15 m under cold flow conditions. A tube bundle consisting of five horizontal staggered rows was completely submerged in the bed. One of the tubes was replaced by a heating cartridge housed in a hollowed copper rod. Five thermocouples distributed at 45º intervals along the copper rod circumference measured the surface temperature and ensured that local effects were included. The bed material was large glass beads of 1.0 mm in diameter while the fines were glass beads of 60 µm in diameter and thus susceptible to entrainment. The fine particles were continuously fed to the fluidized bed and then captured downstream by a filter system. Fluidization was conducted at 101, 600 and 1200 kPa with excess gas velocities (Ug - Umf) of 0.21, 0.29 and 0.51 m/s. Fine particle feed rates were 0, 9.5 and 14.4 kg/h. Two heating rod positions (2nd row and 4th row) were studies.
Overall, the heat transfer coefficient approximately doubled when pressure was increased from 101 to 1200 kPa. At atmospheric conditions, where the slug flow regime occurred, the maximum heat transfer coefficient was at the bottom of the rod, while it moved to the side of the rod at high pressures where the bubbling regime occurred. As the heating rod moving from 2nd row to the 4th row, the averaged heat transfer coefficient increased by respectively 18%, 9% and 6% at 101, 600 and 1200 kPa. The addition of fine particles decreased the average heat transfer coefficient by 10 to 20 W/m2 K where the time – averaged heat transfer coefficient was approximately 220 and 450 W/m2K at 101 kPa and 1200 kPa respectively. There was no effect on the angular profile across the tube surface. The results showed that average heat transfer coefficients matched the correlation developed by Molerus et al. (1995) within a 5% difference across all conditions when fines were not present.
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Chioukh, Nadji. "Wave effects on rigid and elastically-mounted horizontal circular cylinderd placed above a plane bed." Thesis, University of Manchester, 1995. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669701.
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Dornelas, Breno Almeida. "Análise experimental da tensão de cisalhamento mínima para suspensão de partículas em um leito horizontal." Universidade Federal do Espírito Santo, 2009. http://repositorio.ufes.br/handle/10/6248.
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Previous issue date: 2009-12-22A remoção eficiente de cascalhos ainda é um desafio na perfuração de poços para produção de óleo e gás. O ponto crítico corresponde ao estágio horizontal da perfuração que intrinsecamente tende a formar um leito de partículas sedimentadas na parte inferior do poço em perfuração. A erosão desse leito de cascalhos oriundos do solo perfurado depende principalmente da tensão de cisalhamento promovida pelo escoamento do fluido de perfuração. Utilizando uma bancada experimental, composta de sistema para circulação de fluidos, caixa de cascalhos, unidade de bombeio e equipamentos de medição, investiga-se a tensão de cisalhamento mínima necessária para a erosão de um leito em função das propriedades do fluido e das partículas do leito. A área de observação consiste de uma caixa abaixo da linha de escoamento, para partículas calibradas de areia, em um duto de acrílico. Para as medições iniciam-se as bombas com baixa rotação e são feitos incrementos de freqüência. A cada patamar de freqüência são capturadas imagens de partículas carreadas pelo escoamento, registrando a vazão estabelecida. Com a análise do processamento das imagens define-se o momento em que o carreamento das partículas deixa de ser aleatório e esporádico e começa a ser permanente. A tensão de cisalhamento é determinada pela Correlação PKN (de Prandtl, von Kármán e Nikuradse) a partir da vazão mínima necessária para o arraste. Os resultados são obtidos para o escoamento de água e de solução águaglicerina
The efficient hole cleaning is still a challenge in the wellbore drilling for production of oil and gas. The critical point is the horizontal drilling that inherently tends to produce a bed of sediment particles at the bottom of the well. The erosion of this cuttings bed depends mainly on the shear stress promoted by the flow of drilling fluid. The shear stress required to drag cuttings bed is investigate according to the fluid and particles properties, using an experimental assembly, composed of a loop for circulation of fluids, of a particle box, of a pump system, camera and measuring equipment. The area of observation consists of a box below the line of flow, for calibrated sand particles, in an acrylic duct. The test starts with the pumps in low frequency and are made the increments. At each level of frequency are captured images of particles carried and it is records the established flow rate. The erosion criteria is defined when the drag particle no longer be random and sporadic, and begins to be permanent. The shear stress is determined by the PKN correlation (by Prandtl, von Kármán, and Nikuradse) from the minimum flow rate necessary to start the erosion process. Results were obtained for the flow of water; and of water and glycerin solution
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Rojas, Maria Lyda Bolaños. "Tratamento de fenol em reator anaeróbio horizontal de leito fixo (RAHLF) sob condições mesofílicas." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-30012017-093926/.
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Um reator anaeróbio horizontal de leito fixo foi operado a escala de laboratório, visando verificar sua capacidade de degradação de fenol. O RAHLF foi construído em vidro de borosilicato com 100 cm de comprimento e 5,04 cm de diâmetro, preenchido com lodo anaeróbio imobilizado em matrizes de espuma de poliuretano. Prévio à realização do experimento o reator foi operado com substrato sintético, contendo como fontes de carbono glicose, ácido acético e ácido fórmico, atingida a estabilização da matéria orgânica para uma carga orgânica de 1028 mg/L, correspondente a uma remoção de DQO de 98%, foi iniciada a adição de fenol começando com uma concentração de 50 mg/L como única fonte de carbono. A concentração de fenol adicionada variou de 50 a 1200 mg/L e sua degradação foi avaliada através de determinação cromatográfica, utilizando cromatografia gasosa e parâmetros físico-químicos como pH, ácidos voláteis, alcalinidade e DQO. O RAHLF foi operado com um tempo de detenção hidráulica (TDH) de 12,3 horas. Com 50 mg/L, após 33 dias o reator atingiu uma remoção de fenol de 97%. Com 100 mg/L e depois de 148 dias de operação não foi detectado fenol no efluente do reator. Com 300 mg/L e após 58 dias de operação o reator apresentou 99% de remoção e uma concentração no efluente de 0,85 mg/L. Com 600 mg/L, 900 mg/L e 1200 mh/L, após 47, 29 e 7 dias de operação o reator alcançou remoções de 99%. Em todas as concentrações foi observado o predomínio de Methanosaeta, Methanobacterium e cocosmetanogênicos. Em relação à bactéria oxidadora de fenol foi observado o predomínio de coco-bacilos. As altas remoções de fenol observadas neste trabalho são devidas provavelmente à utilização de células imobilizadas.A bench-scale horizontal-flow anaerobic immobilized biomass (HAIB) reactor was assayed aiming to verify its potential use for phenol degradation. The HAIB reactor consisted of a bore-silicate tube (100 cm long; 5.04 cm diameter) filled with polyurethane foam matrices containing immobilized anaerobic sludge. Before being subjected to phenol, the reactor was fed with synthetic substrate at the influent chemical oxygen demand (COD) of 1,028 mg/L achieving 98% of COD removal efficiency. Thereafter, phenol as the sole carbon source was added under step-increasing concentrations from 50 to 1,200 mg/L. Phenol degradation was evaluated by gas chromatographic analysis of influent and effiuent samples. Process monitoring included determinations of pH, volatile acids, alkalinity and COD. The HAIB reactor was operated at a constant hydraulic detention time (HDT) of 12,3 hours. After 33 days with 50 mg/L of phenol in the influent, the reactor achieved 97% of phenol removal efficiency. Successful phenol degradation (efficiency removal of 99%) occurred for influem concentrations of 100, 300, 600, 900 and 1,200 mg/L after 148, 58, 47, 29 and 7 days, respectively. The predominance of Methanosaeta, Methanobacterium and methanogenic cocci could be observed in all the operating conditions, besides the presence of phenol-oxidizing microorganisms as irregular rods. The results indicate that phenol degradation at very high rates can be accomplished in HAIB reactors containing acclimatized biomass.
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Prenzel, Marco [Verfasser]. "Scale-up of horizontal packed bed thermal energy storage units: An in-depth experimental and numerical investigation / Marco Prenzel." Düren : Shaker, 2021. http://d-nb.info/1233548050/34.
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Lima, Cláudio Antônio de Andrade. "Tratamento de esgoto sanitário em reator anaeróbio horizontal de leito fixo (RAHLF): escala piloto." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-16052016-104721/.
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Este trabalho apresenta as avaliações de desempenho, das demandas operacionais e dos fatores intervenientes no aumento da escala da unidade piloto do Reator anaeróbio Horizontal de Leito Fixo (RAHLF) no tratamento de esgoto sanitário após passagem por peneira com malha de 1 mm, durante dois anos de operação. O reator dispunha de volume total de 237,5 1, construídos com tubos comerciais de PVC de 14,5 cm de diâmetro (D), dispostos em cinco módulos horizontais em série de 2,88 m, perfazendo um comprimento total de (L) de 14,4 m e relação de total de L/D de 100. O suporte de imobilização de biomassa, espuma de poliuretano em matrizes cúbicas de 1 cm de aresta, mostrou-se adequado ao desenvolvimento do biofilme. Em partida, sem inoculação prévia, ocorreu a sua consolidação a partir de 70 dias, com predominância de morfologia semelhante a Methanosaeta sp. em relação a da Methanosarcina. Em torno de 90 dias com afluente de 350 mg/l de DQO, observe-se a melhor qualidade do efluente, com valor de 100 mg/l de DQO. Em longa operação ocorreu queda de rendimento e menor reprodutibilidade das previsões do projeto, atribuída aos constantes entupimentos e ineficácia das operações de limpeza, com o comprometimento de volume reacional verificados por estudos de hidrodinâmica. Da investigação das origens dos equipamentos observou-se tratar mais de um efeito local e qualitativamente relacionado à biomassa retida que propriamente quantitativo e extensivo ao longo de todo reator, com produção continuada de polímeros extracelulares, promovendo um efeito sinérgico com os predominantes organismos filamentosos e com os sólidos particulados retidos no leito. Diante das potencialidades desta configuração de reator apontam-se alternativas de mitigação dos entupimentos e o direcionamento dos estudos necessários para novo aumento de escala para o tratamento de esgoto sanitário.This work evaluated the performance, the operational demands and the intervenient factors in the scale-up of the horizontal flow anaerobic immobilized biomass (HAIB) reactor pilot unit, treating domestic sewage previously screened. The operation was monitored for two years. The five- module (2.88 m length each) reactor volume was 237.5 liters and it was built with commercial PVC pipes of 14.5 cm of diameter (D), resulting in a total length (L) of 14.4 m and in a total ratio L/D of approximately 100. The immobilization support, cubic matrices of polyurethane foam (1 cm edge), showed to be suitable for the anaerobic biofilm development. During the start-up, without previous inoculation, the biofilm seemed to be consolidated after 70 days, and Methanosaeta sp. morphology predominated, in detriment of Methanosarcina. With an affluent of 350 mg COD/L, the best reactor performance was observed in about 90 days of operation (100 mg COD/L in the effluent). However, with the continuous operation, its performance decreased and the project predictions did not seem to fit anymore. These facts were probably due to the frequent cloggings ant the inefficiency of the backwashing procedures, leading to a decreasing of the operational volume. The origin of the clogging seemed to be related to the extracellular polymer production, linked to a synergic effect with the filamentous organisms and the particulate solids in the bed. Despite these operational problems, there were found alternatives to mitigate the clogging, and studies about a new scale-up methodology, in order to treat domestic sewage, were strongly recommended.
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Chen, Kaicheng [Verfasser], and Evangelos [Gutachter] Tsotsas. "Modeling and validation of particle drying and coating in a continuously operated horizontal fluidized bed / Kaicheng Chen ; Gutachter: Evangelos Tsotsas." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2020. http://d-nb.info/1219937258/34.
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Chen, Kaicheng Verfasser], and Evangelos [Gutachter] [Tsotsas. "Modeling and validation of particle drying and coating in a continuously operated horizontal fluidized bed / Kaicheng Chen ; Gutachter: Evangelos Tsotsas." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2020. http://d-nb.info/1219937258/34.
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Nardi, Ivana Ribeiro De. "Degradação de benzeno, tolueno, etilbenzeno e xilenos (BTEX) em reator anaeróbio horizontal de leito fixo (RAHLF)." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-18122015-114648/.
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A atividade industrial diversificada tem sido responsável pelo lançamento, no ambiente, de resíduos que contém materiais tóxicos e/ou de difícil degradação. Benzeno, tolueno, etilbenzeno e xilenos (BTEX) são compostos importantes, por estarem presentes em águas superficiais e subterrâneas, geralmente a partir de contaminações por derivadas de petróleo. Enquanto a degradação aeróbia de BTEX já está amplamente entendida e descrita, a aplicação de processos anaeróbios de tratamento, indicados na década de 80 ainda requer mais estudos. Reatores anaeróbios horizontais de leito fixo de bancada preenchidos com cubos de espuma de poliuretano, contendo lodo anaeróbio proveniente de diversas fontes trataram a água residuária sintética a base de proteínas, carboidratos, lipídios, contendo solução etanólica de BTEX e solução de BTEX em detergente comercial; e solução etanólica de BTEX como únicas fontes de carbono. A influência da adição de nitrato e sulfato como aceptores de elétrons na degradação anaeróbia também é discutida. Os reatores foram capazes de remover BTEX nas concentrações testadas de até 15,0 mg/L de cada composto, com tempos de detenção hidráulica de 11,4 horas e 13,5 horas. Os reatores forneceram condições excelentes para o desenvolvimento de biofilme complexo capaz de degradar BTEX, contendo organismos degradadores de BTEX, acetogênicos, acetoclásticos e hidrogenotróficos. Arqueas metanogênicas representaram menos de 0,5% do total de organismos anaeróbios na biomassa dos reatores. O modelo cinético de primeira ordem com residual foi o que melhor representou os dados experimentais e as velocidades de degradações de BTEX, estimadas neste trabalho, foram cerca de 10 a 94 vezes maiores que as encontradas na literatura, em ensaios realizados em microcosmos.The diversified industrial activity has been responsible for discharge in the environment of toxic and/or difficult degradation compounds. Benzene, toluene, ethylbenzene and xylenes (BTEX) are important compounds present in surface and ground waters, usually from petroleum products contamination. While BTEX aerobic degradation is extensively understood and described, anaerobic treatment application, started in the eighties, associated to fundamental studies need to be improved. Bench-scale horizontal-flow anaerobic immobilized biomass reactors filled with polyurethane foam matrices, containing immobilized anaerobic biomass from various sources, treated synthetic substrate containing protein, carbohydrates, lipids, BTEX solution in ethanol and BTEX solution in commercial detergent, as well as BTEX solution in ethanol as the sole carbon source. The influence of the addition of nitrate and sulfate as electron acceptors on anaerobic degradation is also discussed. The reactors were able to remove up to 15.0 mg/L of each BTEX compound, with hydraulic detention time of 11.4 hours and 13.5 hours. The reactors provided excellent conditions for developing a complex biofilm with BTEX-degraders, acetogenic, acetoclastic and hydrogenotrophic microorganisms. Methanogenic archaea were found to represent less than 0.5% of the total anaerobic organisms in the biomass inside the reactors. Residual first order kinetic model fitted well the experimental data and the BTEX degradation rates, estimated in this work, were about 10- to 94-fold higher than those found in the literature, in microcosms studies.
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Erturk, Mehmet Cihan. "Production Performance Analysis Of Coal Bed Methane, Shale Gas, Andtight Gas Reservoirs With Different Well Trajectories And Completiontechniques." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615510/index.pdf.
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The large amount of produced oil and gas come from conventional resources all over the world and
these resources are being depleted rapidly. This fact and the increasing oil and gas prices force the
producing countries to find and search for new methods to recover more oil and gas. In order to meet
the demand, the oil and gas industry has been turning towards to unconventional oil and gas reservoirs
which become more popular every passing day. In recent years, they are seriously considered as
supplementary to the conventional resources although these reservoirs cannot be produced at an
economic rate or cannot produce economic volumes of oil and gas without assistance from massive
stimulation treatments, special recovery processes or advanced technologies.
The vast increase in demand for petroleum and gas has encouraged the new technological development
and implementation. A wide range of technologies have been developed and deployed since
1980. With the wellbore technology, it is possible to make use of highly deviated wellbores, extended
reach drilling, horizontal wells, multilateral wells and so on. All of the new technologies and a large
number of new innovations have allowed development of increasingly complex economically
marginal fields where shale gas and coal bed methane are found.
In this study, primary target is to compare different production methods in order to obtain better well
performance and improved production from different types of reservoirs. It is also be given some
technical information regarding the challenges such as hydraulic fracturing and multilateral well
configuration of the unconventional gas reservoir modeling and simulation. With the help of advances
in algorithms, computer power, and integrated software, it is possible to apply and analyze the effect
of the different well trajectories such as vertical, horizontal, and multilateral well on the future
production performance of coal bed methane, shale gas, and tight gas reservoirs. A commercial
simulator will be used to run the simulations and achieve the best-case scenarios. The study will lead
the determination of optimum production methods for three different reservoirs that are explained
above under the various circumstances and the understanding the production characteristic and profile
of unconventional gas systems.
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Wang, Fei. "Gas-Solid Fluidization: ECVT Imaging and Mini-/Micro-Channel Flow." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1290390285.
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Pobořil, Jan. "Technologie pro zvýšení propustnosti vod v kořenových ČOV." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226874.
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Constructed wetlands are one of alternative solution wastewater treatment. Compared to conventional wastewater plants have many advantages. For example it´s technology saving construction, low operating costs, cleavability diluted wastewater and little or no need for electrical power. There are many publications dealing with Natural Ways wastewater treatment or even constructed wetlands. I decided to look for a thesis on one of the key processes – clogging bed media. The thesis is focused on ways to prevent clogging of bed media, mitigate the consequences and technology to increase hydraulic conductivity of constructed wetlands. The main test method is improving drainage parameters using pulsed filling and emptying of the bed media. This method is a very effective way to achieve quality requirements for effluent water from the treatment plant. Another test method is based on the injection of air into the media bed and sludge extraction using a specially modified industrial vacuum cleaner or pump.
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Fernandes, Bruna Soares. "Influência da origem do inóculo e da adição de sulfato sobre a degradação de BTX em reator anaeróbio horizontal de leito fixo." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-15032016-134215/.
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O desenvolvimento industrial tem, como conseqüência, a maior geração de resíduos, muitos deles tóxicos aos seres vivos. Dentre esses, benzeno, tolueno e xilenos (BTX), derivados do petróleo, estão contaminando aqüíferos por acidentes no transporte e no armazenamento. Por esse motivo, diversas pesquisas têm sido realizadas buscando formas de biodegradar BTX. Esses trabalhos indicam que os principais fatores que podem influenciar a degradação biológica dos BTX são temperatura, pH, disponibilidade de nutrientes, concentração de tóxicos e diversidade de microrganismos. Visando contribuir com o estudo desses fatores, este trabalho teve por objetivo avaliar a influência do inóculo e de aceptores de elétrons no processo de degradação anaeróbia de BTX. Neste trabalho três inóculos foram pesquisados: 1- biomassa proveniente de reator anteriormente submetido à mistura de gasolina comercial e água; 2- biomassa proveniente de reator da estação de tratamento de esgoto da USP - São Carlos; 3- biomassa proveniente de reator tratando água residuária de abatedouro de aves. Os resultados obtidos comprovaram que a origem do inóculo foi fundamental na degradação anaeróbia de BTX, pois os inóculos apresentaram diferentes períodos de adaptação e porcentagens de degradação do tóxico. Depois de 93 dias de operação os inóculos 1, 2 e 3 apresentaram eficiência de remoção de BTX da ordem de 57%, 83% e 90%, respectivamente. O reator com o inóculo 3 foi submetido a condições metanogênica, sulfetogênica com presença e ausência de Ferro (III). Os resultados demonstraram que a degradação dos BTX foi influenciada pelas diferentes condições adotadas. A adição de Fe (III) melhorou a degradação dos BTX, do reator sob condições sulfetogênicas.The industrial development has increased the generation of residues. Some of them are toxics and impact the environment. Benzene, toluene and xylenes (BTX), petroleum sub products, are examples of such toxic compounds. These compounds may contaminate aquifers as a result of accidents during transportation or of leakages of storage tanks. Several factors are reported to affect the biodegradation of BTX, such as: temperature, pH, availability of nutrients, concentration of toxics and diversity of microorganisms. This research aimed to study some of these factors, such as different inoculum sources and different electrons acceptors during BTX degradation processes in an horizontal-flow anaerobic immobilized biomass (HAIB) reactor. In this research three inocula were studied: 1- an adapted microbial community for BTX degradation; 2 - microorganisms collected from a pilot-scale UASB reactor treating domestic wastewater; and 3 - Microorganisms collected from an UASB treating poultry slaughterhouse industry wastewater. The results have shown that the inoculum sources were fundamental to the adaptation period for the toxic biodegradation, producing different BTX removal efficiencies. After 93 days of operation, the inocula 1, 2 and 3 showed BTX removal efficiency of 57, 83 and 90%, respectively. The inoculum 3 was submitted to conditions of methanogesis and sulfetogenesis in the presence and absence of Fe (III). The results demonstrated that BTX degradation was affected by the different conditions adopted, showing that the addition of Fe (III) improved biodegradation in the reactor under sulfate reduction condition.
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Cabral, Ariuska Karla Amorim. "Avaliação do desempenho e estabilidade de um Reator Anaeróbio Horizontal de Leito Fixo (RAHLF) submetido ao aumento progressivo na concentração de matéria orgânica afluente e a cargas de choque orgânicas." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-12072018-092036/.
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Submeteu-se um Reator Anaeróbio Horizontal de Leito Fixo (RAHLF) de bancada, ao aumento progressivo da concentração de matéria orgânica afluente, e a cargas de choque orgânicas, com o objetivo de verificar-se seu desempenho e estabilidade operacional. O RAHLF foi construído com um tubo de boro-silicato de 100 cm de comprimento, 5,0 cm de diâmetro e 1995 ml de volume total e preenchido com lodo anaeróbio imobilizado em matrizes de espuma de poliuretano. O reator foi alimentado, inicialmente, com substrato composto principalmente de carboidratos em concentrações, expressas como Demanda Química de Oxigênio (DQO) de, aproximadamente, 200, 1000 e 2000 mg/l. Posteriormente, os carboidratos foram substituídos por metanol e ácidos voláteis, em concentrações totais, aproximadas, de 2000, 3000, 4000 e 5000 mg DQO/l. Atingido o estado estacionário para cada condição operacional, foram aplicadas cargas de choque, aumentando-se em três vezes o valor da DQO afluente, durante período equivalente ao tempo de detenção hidráulica (sete horas). O sistema apresentou problemas operacionais durante os experimentos com carboidratos, quando submetido a 2000 mg DQO/l, correspondente à taxa volumétrica de carregamento orgânico de 8,77 KgDQO/m3.d. Não foi verificado qualquer problema operacional durante os experimentos com substrato contendo metanol e ácidos voláteis, e o reator apresentou eficiência de remoção de DQO superior a 90%. Para o experimento com DQO afluente igual a 2000 mg/l, os parâmetros cinéticos foram estimados a partir de modelo cinético de 1ª ordem, obtendo-se valor de k1 igual a 0,049 h-1, nos demais experimentos ajustou-se modelo cinético de 2ª ordem com valor médio de k2 equivalente a 2,0 x 10-4 l/mg.h Foram aplicadas cargas de choque orgânicas equivalentes a, aproximadamente, 17; 27; 40 e 47 kgDQO/m3.d. Os efeitos das sobrecargas orgânicas no reator foram transientes em todos os casos, tendo o reator voltado à condição inicial em, no máximo, 15 horas após o início das sobrecargas.A Horizontal flow Anaerobic lmmobilized Sludge Reactor (HAIS) was subjected to progressively increasing concentrations of organic effluent material and to organic shock loads with the purpose of investigating its operational performance and stability. The HAIS, consisting of a 100 cm long, 5 cm diameter borosilicate tube with a total volume capacity of 1995 mL, was filled with anaerobic sludge immobilized in foam and polyurethane matrixes. The reactor was initially fed with a substrate composed mainly of carbohydrates in concentrations, expressed as Chemical Oxygen Demand (COD), of approximately 200, 1000 and 2000 mg/L. These carbohydrates were later replaced by methanol and volatile acids in total concentrations of 2000, 3000, 4000 and 5000 mg COD/L. Shock loads were applied after each operational condition became stationary, with the effluent COD tripled for a period equivalent to the hydraulic detention time (seven hours). The system presented operational problems during the experiments with carbohydrates when subjected to 2000 mg DQO/l, which corresponded to a volumetric organic load index of 8,77 Kg COD/m3.d. No operational problems were detected during the experiments with substrates containing methanol and volatile acids, and the reactor presented a COD removal efficiency of over 90%. The kinetic parameters for the COD effluent with 2000 mg/L were estimated based on a first arder kinetic model, which resulted in a k1 value of 0,049 h-1, while a kinetic model of the second order was used for the remaining experiments, with a mean value of k2 equivalent to 2,0 x 10-4 L/mg.h. Organic shock loads of approximately 17; 27; 40 and 47 kg COD/m3.d were applied. The effects of the organic overloads on the reactor were transient in every case, with the reactor returning to its initial condition at the most 15 hours after the beginning of the overloads.
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Rodrigues, Caroline. "Modelagem e simulação dinâmica de reatores de leito fixo." Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/4068.
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Previous issue date: 2011-02-25Universidade Federal de Sao Carlos
This work investigated numerical methods in the solution of mathematical models of fixed-bed reactors. For the reactors modeling and simulation, two numerical methods were used: sequencing method (SM) and finite volume method (FVM). There were also proposed two mathematical models: the pseudo-homogeneous model and the dimensionless one, which is based on the Peclet (Pe) and Biot (Bi) numbers. A horizontal-flow anaerobic immobilized sludge (HAIS) reactor developed in bench scale and after a scale-up, reducing the COD in the wastewater treatment was simulated by sequencing method, varying the numbers of mesh; a tubular fixed-bed reactor with biomass immobilized for the startup period of lactic acid fermentation, also simulated by sequencing method and compared with experimental data; and was also evaluated the precision of sequencing and finite volume methods over the reactor s profile, varying the Peclet e Biot numbers. The models development was based on studies about hydrodynamics and biochemistry kinetics. Both methods described satisfactorily the behavior of the reactors in the performed simulations, but in high values of Peclet, the finite volume method generated inadequacies such as oscillatory responses and over the limit. This paper is an elucidation to sequencing method, which besides its huge range and simplicity, still is not so studied neither known, because it s a recent method.
Este trabalho investigou metodos numericos na solucao de modelos matematicos para reatores de leito fixo. Para a modelagem e simulacao dos reatores, foram utilizados dois metodos numericos: metodo da sequencia (SM) e metodo dos volumes finitos (FVM). Foram propostos dois modelos matematicos: o pseudo-homogeneo e o adimensional, sendo este ultimo baseado nos numeros de Peclet (Pe) e Biot (Bi). Um reator anaerobio horizontal de leito fixo (RAHLF) desenvolvido inicialmente em escala de bancada e posterior aumento de escala na reducao da DQO de aguas residuarias foi simulado pelo metodo da sequencia, variando-se o numero de malhas; um reator tubular de leito fixo com biomassa anaerobia imobilizada no periodo da partida da fermentacao de acido latico, tambem simulado pelo metodo da sequencia e comparado com dados experimentais; e avaliou-se a precisao dos metodos da sequencia e dos volumes finitos sobre o perfil da concentracao de um reator, variando-se os valores de Peclet e Biot. O desenvolvimento dos modelos foi baseado em estudos sobre caracteristicas hidrodinamicas do sistema e de cinetica bioquimica. Ambos os metodos descreveram satisfatoriamente o comportamento dos reatores nas simulacoes realizadas, porem em valores elevados de Peclet, o metodo dos volumes finitos gerou inadequacoes como respostas oscilatorias e superiores ao limite. Este trabalho foi uma elucidacao ao metodo da sequencia, que apesar da sua grande abrangencia e simplicidade, por ser um metodo recente, ainda e pouco estudado e conhecido.
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Chaudhry, Ahmed Rizwan. "Prediction of bend pressure losses in horizontal lean phase pneumatic conveying." Thesis, University of Greenwich, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405306.
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Ceyhan, Ozlem. "Aerodynamic Design And Optimization Of Horizontal Axis Wind Turbines By Using Bem Theory And Genetic Algorithm." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610024/index.pdf.
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An aerodynamic design and optimization tool for wind turbines is developed by using both Blade Element Momentum (BEM) Theory and Genetic Algorithm. Turbine blades are optimized for the maximum power production for a given wind speed, a rotational speed, a number of blades and a blade radius. The optimization variables are taken as a fixed number of sectional airfoil profiles, chord lengths, and twist angles along the blade span. The airfoil profiles and their aerodynamic data are taken from an airfoil database for which experimental lift and drag coefficient data are available. The BEM analysis tool developed is first validated with the experimental data for low wind speeds. A 100 kW wind turbine, which is used in the validation, is then optimized. As a result of the optimization, the power production is improved by 40 to 80 percent. The optimization methodology is then employed to design a 1MW wind turbine with a 25m radius.
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Filho, Isnar Pereira da Fonseca. "Belo Horizonte Bem Querer: versos sinfônicos com ásperas dissonâncias." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/ECAP-8GDSNF.
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Cette dissertation traite de plusieurs images contradictoires engendrées à propos de Belo Horizonte, depuis ses origines jusquau début des années 1970, dans le poème Belo Horizonte Bem Querer, d Henriqueta Lisboa. Conçue daprès lideal républicain de lordre, lhygiène et la discipline, la capitale de Minas Gerais a été construite de sorte que de son plan en papier naquît une société idéale. Le caractère arbitraire de ses formes suscite une appropriation de ses espaces qui gagnent progressivement de nouveaux contours, tout en transformant la ville idéalisée en ville vécue. En tant que lecteurs de lespace urbain, les écrivains, par lanalyse de différents regards sur Belo Horizonte, ont contribué de manière importante en faveur de la connaissance de la capitale. Dans le cas d Henriqueta Lisboa, lauteur perçoit les contradictions de cette ville à partir dun point de vue de lintérieur vers lextérieur, ce qui permet la compréhension de la fluidité de lessence citadine. Lectrice attentive de cet espace qui change constamment, Henriqueta ouvre dautres perspectives pour que son lecteur puisse voir la ville à travers dautres yeux. Ce travail porte donc sur cet univers de multiples images, ayant comme point de départ Belo Horizonte Bem Querer, Belo Horizonte: la ville écrite et le livre Belo Horizonte: mémoire historique descriptive histoire ancienne et histoire moyenne, volumes I et II, dAbilio BarretoEsta dissertação estuda várias imagens contraditórias engendradas em torno de Belo Horizonte, das origens ao início dos anos 70, no poema 'Belo Horizonte Bem Querer', de Henriqueta Lisboa. Planejada a partir do ideal republicano de ordem, higiene e disciplina, a capital de Minas foi construída para que de sua planta de papel nascesse uma sociedade ideal. A arbitrariedade de suas formas instiga uma apropriação de seus espaços, que pouco a pouco vão ganhando novos contornos, transformando a cidade idealizada em vivida. Como leitores do espaço urbano, os escritores, ao analisarem os diversos olhares voltados para Belo Horizonte, contribuíram de modo relevante para o conhecimento da capital. Em se tratando de Henriqueta Lisboa, a autora percebe as contradições a partir de uma perspectiva de fora para dentro, o que permite a compreensão da fluidez da essência citadina. Leitora atenta desse espaço em constante transformação, abre novas perspectivas para que seu leitor aprenda a ver a cidade com outros olhos. É a respeito desse universo de múltiplas imagens que esta dissertação se debruça, tendo como ponto de partida 'Belo Horizonte Bem Querer', 'Belo Horizonte: a cidade escrita' e o livro 'Belo Horizonte: memória histórica e descritiva - história antiga e história média', volumes I e II, de Abílio Barreto
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Andree, Kai. "Horizontale Fusionen bei räumlichem Wettbewerb : eine modelltheoretische Analyse intra- und interregionaler Fusionen." Phd thesis, Universität Potsdam, 2014. http://opus.kobv.de/ubp/volltexte/2014/6920/.
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Fusionen stellen einen zentralen Baustein der Industrieökonomik dar. In diesem Buch wird der Frage nachgegangen, welchen Einfluss die räumliche Dimension auf eine Fusion ausübt. Dabei wird ein Grundmodell entwickelt und über dieses hinaus eine Vielzahl Erweiterungen präsentiert. Der Leser erhält somit die Möglichkeit ein tiefes Verständnis für Fusionen bei räumlichem Wettbewerb zu erlangen.The analysis of mergers ia a central element of industrial organization. In this book the influence of spatial competition on mergers is analyzed. A basic model is developed and enhanced to take into account different economic environments. The reader gets the possibility to understand the effects of mergers with spatial competition.
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Baues, Stefan Heinz. "Untersuchungen zum Tragverhalten sattelgelagerter Zylinderschalen bei horizontaler seitwärts gerichteter Belastung." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983398968.
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Schenkel, Torsten [Verfasser]. "Thermische Konvektion in einem Zweischichtsystem bei horizontalem Temperaturgradienten / Torsten Schenkel." Karlsruhe : KIT-Bibliothek, 2002. http://d-nb.info/1013897226/34.
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Strauss, Martin. "Untersuchung der Pfropfendynamik und -stabilität bei der vertikalen und horizontalen Pfropfenförderung." [S.l.] : [s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11814257.
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Silva, Jaqueline Damasceno. "Uma análise da variação dos níveis de equidade de acesso e de igualdade horizontal nos resultados de saúde no Brasil entre 1998 e 2013: expressões da relação entre o estado de bem-estar social e os determinantes sociais de saúde." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/8720.
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Made available in DSpace on 2018-07-18T15:18:52Z (GMT). No. of bitstreams: 2 Dissertação - Jaqueline Damasceno Silva - 2018.pdf: 3790741 bytes, checksum: e3fb3ef24fba8a6172100b0c07148574 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-07-12
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
This paper presents a discussion about the relationship between income distribution patterns, social determinants of health and the welfare state of the Brazilian population, considering the concepts of equality, equity and social justice. Its aim is to understand the dynamics between the changes in the Brazilian economic and social scenario and the guidelines for health and the changes in the level of equity of access to health and in the level of horizontal equality of the health outcomes of the population, among the social strata in Brazil between 1998, 2003, 2008 and 2013. To do this, as indicated in the methodology, a presentation was made of the changes in the demographic, socioeconomic and epidemiological profile of the population through the synthesis of historical data present in the National Health Plans and Research Reports of health performed between 1998 and 2013. In addition, a set of indicators was compiled which is composed of the Standard Gini Concentration Index and extended with parameters of aversion to inequality, by the Lorenz Concentration Curves, and by the Index decomposition by the Social Determinants of Health, to be able to measure variations in the level of equity of access and horizontal equality in health outcomes between 1998 and 2013. The results point to improvements both in the equity of access to health services and in the horizontal equality in health outcomes up to 2008, changes mainly associated with the expansion of primary health care strategies, but a decrease of this improvement in some indicators in 2013.
Este trabalho apresenta uma discussão acerca da relação entre os padrões de distribuição da renda, os determinantes sociais de saúde e o Estado de Bem-Estar Social da população brasileira, considerando os conceitos de igualdade, equidade e justiça social. Seu objetivo é compreender a dinâmica entre as alterações no cenário econômico e social brasileiro e nas diretrizes para saúde e as alterações no nível de equidade de acesso à saúde e no nível de igualdade horizontal dos resultados de saúde da população, entre os estratos sociais no Brasil entre 1998, 2003, 2008 e 2013. Para isso, como indicado na metodologia, foi realizada uma apresentação das alterações dos perfis demográfico, socioeconômico e epidemiológico da população por meio da síntese dos dados históricos presentes nos Planos Nacionais de Saúde e dos Relatórios das Pesquisas de saúde realizadas entre 1998 e 2013. Além disso, foi elaborado um conjunto de indicadores composto pelo Índice de Concentração de Gini padrão e estendido com parâmetros de aversão à desigualdade, pelas Curvas de Concentração de Lorenz e pela decomposição do Índice pelos Determinantes Sociais de Saúde, para assim, ser possível mensurar as variações no nível de equidade de acesso e igualdade horizontal nos resultados de saúde entre os anos de 1998 e 2013. Os resultados apontam melhoras tanto na equidade de acesso aos serviços de saúde como na igualdade horizontal nos de resultados de saúde até 2008, mudanças associadas, principalmente, à expansão das estratégias de atenção primária à saúde, mas uma diminuição dessa melhora em alguns indicadores em 2013.
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Löbl, Stefan. "Wärmeübergang bei der Verdampfung von Kohlendioxid an horizontalen Einzelrohren aus unterschiedlichen Materialien." Dresden TUDpress, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2954908&prov=M&dok_var=1&dok_ext=htm.
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Löbl, Stefan. "Wärmeübergang bei der Verdampfung von Kohlendioxid an horizontalen Einzelrohren aus unterschiedlichen Materialien /." Dresden : TUDpress, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2954908&prov=M&dok_var=1&dok_ext=htm.
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Kussin, Johannes. "Experimentelle Studien zur Partikelbewegung und Turbulenzmodifikation in einem horizontalen Kanal bei unterschiedlichen Wandrauhigkeiten." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970940297.
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Claus, Christian [Verfasser]. "Zusammenhang von horizontaler Weichgewebsdicke und Sondierungstiefen bei gesunden und erkrankten Implantaten / Christian Claus." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2017. http://d-nb.info/1139169955/34.
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Heller, Frank. "Entwicklung und klinische Erprobung einer Messapparatur zur Untersuchung der horizontalen interdentalen Kräfte bei kieferorthopädischen Patienten." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964814331.
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Andree, Kai [Verfasser], and Klaus [Akademischer Betreuer] Schöler. "Horizontale Fusionen bei räumlichem Wettbewerb : eine modelltheoretische Analyse intra- und interregionaler Fusionen [[Elektronische Ressource]] / Kai Andree. Betreuer: Klaus Schöler." Potsdam : Universitätsbibliothek der Universität Potsdam, 2014. http://d-nb.info/104872705X/34.
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Buhl, Matthias. "Spin Transfer Torque-induziertes Schalten von Nanomagneten in lateraler Geometrie bei Raumtemperatur." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-139909.
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Das Schalten und das Auslesen der magnetischen Ausrichtung einzelner winziger magnetischer Informationsspeicher müssen zu wirklich nanoskopischer Dimension entwickelt werden, um mit der Miniaturisierung von modernen, nanoelektronischen Bauteilen Schritt zu halten. Daher sind neue Konzepte, den magnetischen Zustand von Nanostrukturen elektronisch gezielt zu beeinflussen, derzeitig im Mittelpunkt wissenschaftlicher Untersuchungen. Diese Arbeit befasst sich mit dem zuverlässigen Einstellen der Magnetisierung eines rein horizontal kontaktierten, nanoskopischen Magneten, in zwei stabile Zustände. Ein spinpolarisierter Strom wird bei Raumtemperatur in eine Leiterbahn unterhalb des magnetischen Nanopillars injiziert. Spindiffusion durch den Kontakt zwischen der Leiterbahn (Cu) und dem Pillar (CoFe) ruft eine Spin-Akkumulation im Nanopillar hervor, der durch den Spin Transfer Torque-Effekt (STT) vermittelt wird. Bei diesem Prozess verursachen die akkumulierten Elektronenspins ein auftretendes Netto-Moment, das senkrecht auf die Magnetisierungsorientierung des Nanopillars wirkt und so das Schalten ermöglicht. In den STT-induzierten Schaltexperimenten wird der magnetische Zustand des Nanopillars durch eine bildgebendes Messverfahren mittels Rasterröntgentransmissionsmikroskopie (STXM) erfasst. So konnte gezeigt werden, dass sich die Magnetisierung des Pillars auch gegen das Oersted-Feld des Schaltstroms reversibel schalten lässt“Changing and detecting the orientation of nanomagnetic structures, which can be used for durable information storage, needs to be developed towards true nanoscale dimensions for keeping up the miniaturization speed of modern nano electronic components. Therefore, new concepts for controlling the state of nano magnets are currently in the focus of research in the field of nanoelectronics. Here, we demonstrate reproducible switching of a purely metallic nanopillar placed on a lead that conducts a spin-polarized current at room temperature. Spin diffusion across the metal-metal (Cu to CoFe) interface between the pillar and the lead causes spin accumulation in the pillar, which may then be used to set the magnetic orientation of the pillar by means of Spin Transfer Torque (STT). In our experiments, the detection of the magnetic state of the nanopillar is performed by direct imaging via scanning transmission x-ray microscopy (STXM)” [1]. Therefore it could be demonstrated, to reversibly switch the nanopillar’s magnetic state even against the Oersted field which is induced by the switching current. Furthermore we could show, that magnetization switching is possible by a pure spin current that is diffusively transported beneath the nanopillar
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Eberle, Jens Christian [Verfasser], and Ulrich [Akademischer Betreuer] Lotzmann. "Zum initialen Einfluss einer reversibel veränderten Vertikaldimension bei Totalprothesenträgern auf die horizontale Projektion des Körperschwerpunktes / Jens Christian Eberle. Betreuer: Ulrich Lotzmann." Marburg : Philipps-Universität Marburg, 2011. http://d-nb.info/1013075226/34.
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Merzsch, Matthias [Verfasser], Hans Joachim [Gutachter] Krautz, and Fabian [Gutachter] Mauß. "Wärmeübergang und Druckverlust bei der Kondensation von Wasserdampf im horizontalen Rohr bei Drücken bis 10 bar / Matthias Merzsch ; Gutachter: Hans Joachim Krautz, Fabian Mauß." Cottbus : BTU Cottbus - Senftenberg, 2020. http://d-nb.info/1203626444/34.
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Asegehegn, Teklay Weldeabzgi [Verfasser], and Hans Joachim [Akademischer Betreuer] Krautz. "Investigation of bubble hydrodynamics in gas-solid fluidized beds containing immersed horizontal tube banks for lignite drying application / Teklay Weldeabzgi Asegehegn. Betreuer: Hans Joachim Krautz." Cottbus : Universitätsbibliothek der BTU Cottbus, 2012. http://d-nb.info/1019707305/34.
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Tomforde, Cord [Verfasser]. "Einfluss der Mikrostruktur auf die Benetzbarkeit und den Wärme- und Stoffübergang bei der Absorption an horizontalen Rohren / Cord Tomforde." München : Verlag Dr. Hut, 2020. http://d-nb.info/1219476420/34.
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Karapetow, Nico [Verfasser]. "Untersuchung der Kondylenposition nach supraforaminaler horizontaler Osteotomie (SHO) bei unimaxillärer mandibulärer Umstellungsosteotomie mit Hilfe der digitalen Volumentomographie / Nico Karapetow." Greifswald : Universitätsbibliothek Greifswald, 2014. http://d-nb.info/1052102662/34.
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Jopen, Eva-Maria [Verfasser]. "Biomechanischer Vergleich der winkelstabilen Plattenosteosynthese zu Drahtcerclagen und kanülierten Schrauben bei horizontaler Patellafraktur an fixierten Kniekadavern / Eva-Maria Jopen." Köln : Deutsche Zentralbibliothek für Medizin, 2017. http://d-nb.info/1139863533/34.
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Brett, Angela. "Verfahrensdauer bei Verfassungsbeschwerdeverfahren im Horizont der Rechtsprechung des Europäischen Gerichtshofs für Menschenrechte zu Art. 6 Abs. 1 S. 1 EMRK." Berlin Duncker & Humblot, 2007. http://d-nb.info/995470952/04.
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Perdigao, Tadeu Starling. "A experiência estética na cidade e suas implicações éticas: transformação urbana e promoção do bem comum no espaço público de Belo Horizonte." Universidade Federal de Minas Gerais, 2009. http://hdl.handle.net/1843/RAAO-7YKGLB.
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This work focuses on the issue of aesthetic experience in the city, in order to investigate possible implications and developments of ethical nature in citizens everyday life, through the analysis of the relation between urban transformation process and the promotion of common good in the public space of Belo Horizonte. As specific object of study, among the innumerable elements that configure the physical dimension of the citys public spaces, it was chosen a set of permanence spaces and spaces that provide support to displacements of pedestrians in the area inside the current perimeter of Avenue do Contorno, which was defined as research universe. The approached spaces correspond tosquares of distinct characteristics, spaces remained of urban transformation, as well as linear spaces potentially rich in the capacity of receiving the citizens in their journeys through the city. Through direct observation procedures, aleatory displacements, establishment of journeys and photographic records accomplished in the area originally designed to Belo Horizonte by Engineer Aarão Reis in the XIX century, diverse data was raised which enables to make considerations about the need of assuring a good quality public space to the citizens. The hypothesis defended is that the city, when aesthetically experienced, can provide the subject of conditions for its improvement as citizen. Accordingly, the work proposes a reflection on the interlacing, in publicspace, of the concept of aesthetic experience and of ethical issues involved in this kind of experience and started by it.Este trabalho aborda a questão da experiência estética na cidade, no sentido de investigar possíveis implicações e desdobramentos de ordem ética na vida cotidiana dos cidadãos, através da análise da relação entre os processos de transformação urbana e de promoção do bem comum no espaço público de Belo Horizonte. Como objeto específico de estudo, dentre os inúmeros elementos que configuram a dimensão física do espaço público da cidade, foi eleito um conjunto de espaços de permanência e de suporte a deslocamentos de pedestres na área compreendida dentro do perímetro atual da Avenida do Contorno, que foi definida como universo de pesquisa. Os espaços abordados correspondem a praças de características distintas, espaços remanescentes de transformações urbanas, assim como espaços lineares potencialmente ricos na capacidade de acolher os cidadãos em seus percursos pela cidade. Através de procedimentos de observação direta, de deslocamentos aleatórios, do estabelecimento de percursos e de registros fotográficos realizados na área originalmente projetada para Belo Horizonte pelo Engenheiro Aarão Reis no século XIX, foram levantados dados diversos que permitem tecer considerações a respeito da necessidade de se garantir aos cidadãos um espaço público de qualidade. A hipótese defendida é a de que a cidade,quando experimentada esteticamente, pode propiciar ao sujeito condições para seu aprimoramento enquanto cidadão. Nesse sentido, o trabalho propõe uma reflexão sobre o entrelaçamento, no espaço público, do conceito de experiência estética e das questões de natureza ética envolvidas nesse tipo de experiência e desencadeadas por ela.
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Brett, Angela [Verfasser]. "Verfahrensdauer bei Verfassungsbeschwerdeverfahren im Horizont der Rechtsprechung des Europäischen Gerichtshofs für Menschenrechte zu Art. 6 Abs. 1 S. 1 EMRK. / Angela Brett." Berlin : Duncker & Humblot, 2009. http://d-nb.info/1238358861/34.
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Araya, Tadashi. "Grain fabrics formed on horizontal to gently inclined sandy erodible beds under unidirectional, oscillatory and combined flows, with special reference to the dependence of imbrication angles on grain elongation and grain size." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147833.
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Plucinski, Matthew Paul Mathematics & Statistics Australian Defence Force Academy UNSW. "The investigation of factors governing ignition and development of fires in heathland vegetation." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Mathematics and Statistics, 2003. http://handle.unsw.edu.au/1959.4/38702.
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Heathlands typically experience regimes consisting of frequent and intense fires. These fire regimes play important roles in the lifecycles and population dynamics of all species in these communities. Prescribed fire is commonly applied to heathlands to minimise the risk of wildfires as well as to promote biodiversity. Ignitions in heathlands tend to either be unsustainable, or quickly develop into rapidly spreading intense fires. This presents a major problem for the application of prescribed fire and is the primary focus of this thesis. Heathland ignition has been investigated in three sections; litter ignition; vertical development of fire into the shrub layer; and horizontal spread through the shrub layer. These were studied in laboratory experiments using miniature versions of field fuels. Ignition success in litter layers was related to the dead fuel moisture content. Litter type, ignition source, and presence of wind were found to affect the range of ignitable fuel moisture contents of a litter bed. The effect of litter type was best explained by density. Dense litter beds required drier conditions for ignition than low density litter beds. The vertical development of fire into shrubs was mostly dependent on live fuel moisture content, but crown base height, presence of wind, ignition source, shrub height and the percentage of dead elevated fuel were also important. Horizontal spread of fires through shrub layers was most affected by the presence of a litter layer, with nearly all ignitions successful when there was an underlying litter fire. Fire spread would only occur in shrubs without a litter layer when the shrub layer was dense and dry, or had a substantial dead fuel component. Spread was more likely to be sustained when there was wind. Models predicting the moisture content of dead fuels were tested in heathlands, and as would be expected those that can be calibrated for different fuel types were found to have the best performance. Fuel moisture content and fuel load models were reviewed for heathlands, and a number of recommendations for future research were made.
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Oljelund, David. "Dimensionering och konstruktion av passiv mekanisk pitch för småskaliga horisontalaxlade vindkraftverk." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-42348.
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För vindkraftverk i mindre skala används i huvudsak två sätt att avlasta vid höga vindhastigheter, stallreglering och girning ur vind. En tredje metod är att pitcha rotorbladet till en mindre attackvinkel. Då minskar belastningen på rotorbladet samtidigt som effektgenerering kan bibehållas. Arbetet redovisar en konstruktion för en fjädrande passiv mekanisk pitch som avgränsats till att enbart dimensionera en vridfjäder och tre lager. Konstruktionen riktas mot horisontalaxlade vindkraftverk med tre rotorblad med en rotordiameter upp till 20m. Ett idealt rotorblad modelleras matematiskt för att ta fram dimensionerande krafter och moment. Utifrån detta kan sedan vridfjäder och lager dimensioneras. Konstruktionen tillsammans med dimensioneringen visar att belastning av rotorbladet kan reduceras samt att krafter som är kopplad till effekten kan hållas mer eller mindre konstant för vindhastigheter 16 till 24 m/s. Resultat av dimensionering visar att både vridfjäder och lager kan relativt enkelt anpassas till olika axeldiametrar. Slutsatserna blir att om dimensionering görs enligt arbetet är det, åtminstone i teorin, möjligt att uppnå det önskade beteendet för pitchen. För vidare arbete och verifiering rekommenderas bland annat att göra reella tester för vridfjädern för att bestämma dess precision på grund av fjäderns små vinkelutslag.For small-scale wind turbines, there are mainly two ways of reducing loads at high wind speeds, stall regulation and yaw the rotor out of wind. A third method is to pitch the rotor blade to a smaller angle of attack. This reduces the load on the rotor blade while maintaining power generation. The following work presents a design for a spring based passive mechanical pitch that is limited to only dimensioning a torsion spring and three bearings. The design is aimed at horizontal axis wind turbines with three rotor blades with a rotor diameter up to 20m. An ideal rotor blade is mathematically modeled to produce the forces and torques needed in order to properly dimension the torsion spring and bearings. The design shows that the load of the rotor blade can be reduced and that forces connected to the power can be kept more or less constant for wind speeds 16 to 24 m / s. The results of sizing show that both the torsion spring and bearings can be adapted to different shaft diameters relatively easy. The conclusions are that if dimensioning is done according to the presented results, it is possible, at least in theory, to achieve the desired behaviour. For further development and verification it is recommended to do real tests for the torsion spring to determine its precision due to small angle displacement in the spring.
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You-Hua, Chen, and 陳尤華. "Studies on the Horizontal Jet in a Two-Dimensional Bed." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/58473683580900211759.
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碩士中原大學
化學工程研究所
86
The studies of horizontal penetration jets were carried out in a two-dimensional bed with a cross section of 15 mm * 400 mm.No background fluidized gas was discharged into the bed. The bedmaterials were glass beads with various diameters of 0.069,0.081, 0.137, 0.230, 0.545, 0.650 and 0.920 mm. The effects of particle sizes, nozzle diameters and velocities on horizontal penetration jets were investigated. Three gas discharge modes, voids, transition regions and jets were observed. The void cam be formed at lower gas velocities or higher static bed heihgts. When the gas velocityincreased gradually, jets would form from voids. For horizontal jet penetration lengths from multi-nozzles,the back jet penetration length was longer than the front jetpenetration length. The effect of the back jet penetrationlength on the front jet penetration length was insignificant.
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Hsu, Rong-Hong, and 徐榮鴻. "The Design and Analysis of the Horizontal Active Carbon Bed." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/49453497980271262122.
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碩士國立清華大學
化學工程學系
86
The analysis of the active carbon adsorbed bed is our topic. In the adsorbed system, we use vertical and honrizontal inlet airsystem to check how the air flows and the difference of the air system.From the experiment, we can know that the flow field of the horizontal active carbon bed is complecated.In the verticalinlet air system, we can find that half of the bed is used for adsorbtion. In the horizontal inlet air system, we can also findthe post-half bed is used for adsorbtion and there are some vortexin some area.Finally, we know that the flow field of the horizontalactive carbon system is very complicated and it is not a good design.
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HUANG, ZHI-FENG, and 黃志峰. "Studies on the aerated tumbling bed within a horizontal rotating cylinder." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/66293317080390641248.
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Liu, Chin Ming, and 劉晉銘. "Pressure Fluctuations in a Fluidized Bed Equipped with Multi- Horizontal-Nozzles Gas Distributor." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/75481706091839849170.
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碩士中原大學
化學工程研究所
84
All the experiments were conducted in a 0.3m * 0.6m fluidized bed column equipped with multi-horizontal-nozzle gas distributor . Below the distributor there is a windbox which is built with two indepent parts The design objective of the widbox and the distributor is to cause a rotational flow of the bed material within the fluidized bed. Pressure signals were measured by a probe which could be placed at a desired position. The mean pressure drop, mean amplitude of pressure drop, the standard deviation of amplitude and the coefficient of variance of amplitude was calculated by statistic analysis. The effect of air velocity, static bed height, open ratio of distributor and velocity ratio on the performance of pressure fluctuations were investigated. The results showed that if gas velocity or static bed height increased, mean amplitude and standard deviation of amplitude raised, but coefficient of variance of amplitude reduced. When the velocity ratio increased the standard deviation of amplitude and coefficient of variance of amplitude increased. When the value of coefficient of variance was low, this implied that the fluctuation degree of amplitude was similar to mean amplitude, a plausible explanation for this phenomenon is that the degree of gas-solid mixing was similar at different measurement positions.
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Lin, Mei-Shiou, and 林美秀. "Gas Mixing in a Fluidized Bed Equipped with a Multi-Horizontal-Nozzles Distributor." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/7a9vrk.
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碩士中原大學
化學工程研究所
92
Abstract One of the most important advantages of the fluidized bed is the well mixed between gas and solid. For commercial applications, the high efficient of fluid-solid contact is usually emphasized. For improvement or innovation, how to enhance the efficiency of gas solid mixing, mass transfer coefficient and heat coefficient are focused. In a conventional fluidized bed, bubbles pass through the bed from bottom to the top. The inherent radial momentum deficiency of the fluidizing gas leads to vertical mixing many times faster than lateral mixing. For commercial application, how to improve the efficiency of mixing in the lateral direction becomes an important topic to the engineers. The internal circulating fluidized bed, an bubbling fluidized bed innovated by employing un-uniformly gas distribution within the bed to achieve internal particle circulation, should increase the particle moment and mixing efficient in the horizontal direction. In this study, an internal circulating fluidized bed with a dimension of 40 x 20cm equipped with horizontal nozzles type distributor was used. All the gas jets from nozzles are towards the same direction, parallel with the long side. The circulation of particles will be enhanced by adjusting the distribution of gas flow within the bed. It can be said that the gas diffusion rate is higher in the direction parallel to the long axis and lower in the direction perpendicular to that. In this study, the superficial gas velocity, static bed height and gas distributor type are used as the main parameter. Carbon dioxide is use as the tracer gas. The analysis of standard deviation of the tracer concentration profile will be used as the mixing index. The relationship between the mixing index between the operation parameter will be discussed. The experimental results indicate that the effect of superficial and open-area ratio are more significant on gas mixing than static bed height. To compare the gas mixing performances of different distributor, two types of distributor were compared, horizontal nozzles distributor and perforate. The result indicates that the gas mixing performance of horizontal nozzles is better than perforated plate.
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Chang, Che Hsin, and 張哲馨. "Gas Discharge Modes at a Single Horizontal Nozzle in a Two- Dimensional Fluidized Bed." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/55965531359400555208.
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碩士中原大學
化學工程研究所
82
The gas discharge modes, bubbling and jetting formed at a single horizontal nozzle in a gas-fluidized bed were investigated by visual observation. The inside diameter of nozzles used in this study were 3,4.5,6,7.5 and 9mm respectively. The gas velocity through the nozzle was in the range from 1 to 130 m/s. The primary air velocitywaskept at Umf. Bubbling, jetting and the transition of gas discharge modes were analyzed by high speed cine photography. The effect of the nozzle diameter,gas injection velocity and particle diameter are studied . This experimental length increases with the nozzle velocity as well as nozzlediameter.The phase diagram of bubbling, jetting and transition zone are mapped Froude number and Dp/Do as the parame- ter. It is shown experimentally that if the modified Fr in the phase diagram isused then there are three distinct regimes, the bubble regime, the transition zone between bubbling and jetting and the jetting regime.