83 resultados para Tolstoy, Leo, graf, 1828-1910.


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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This work proposes a model to investigate the use of a cylindrical antenna used in the thermal method of recovering through electromagnetic radiation of high-viscosity oil. The antenna has a simple geometry, adapted dipole type, and it can be modelled by using Maxwell s equation. The wavelet transforms are used as basis functions and applied in conjunction with the method of moments to obtain the current distribution in the antenna. The electric field, power and temperature distribution are carefully calculated for the analysis of the antenna as electromagnetic heating. The energy performance is analyzed based on thermo-fluid dynamic simulations at field scale, and through the adaptation in the Steam Thermal and Advanced Processes Reservoir Simulator (STARS) by Computer Modelling Group (CMG). The model proposed and the numerical results obtained are stable and presented good agreement with the results reported in the specialized literature

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In the artificial lift method by Electrical Submersible Pump (ESP), the energy is transmitted for the well´s deep through a flat electric handle, where it is converted into mechanical energy through an engine of sub-surface, which is connected to a centrifugal pump. This transmits energy to the fluid under the pressure form, bringing it to the surface In this method the subsurface equipment is basically divided into: pump, seal and motor. The main function of the seal is the protect the motor, avoiding the motor´s oil be contaminated by oil production and the consequent burning of it. Over time, the seal will be wearing and initiates a contamination of motor oil, causing it to lose its insulating characteristics. This work presents a design of a magnetic sensor capable of detecting contamination of insulating oil used in the artificial lift method of oil-type Electrical Submersible Pump (ESP). The objective of this sensor is to generate alarm signal just the moment when the contamination in the isolated oil is present, enabling the implementation of a predictive maintenance. The prototype was designed to work in harsh conditions to reach a depth of 2000m and temperatures up to 150°C. It was used a simulator software to defined the mechanical and electromagnetic variables. Results of field experiments were performed to validate the prototype. The final results performed in an ESP system with a 62HP motor showed a good reliability and fast response of the prototype.

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The demand for alternative sources of energy drives the technological development so that many fuels and energy conversion processes before judged as inadequate or even non-viable, are now competing fuels and so-called traditional processes. Thus, biomass plays an important role and is considered one of the sources of renewable energy most important of our planet. Biomass accounts for 29.2% of all renewable energy sources. The share of biomass energy from Brazil in the OIE is 13.6%, well above the world average of participation. Various types of pyrolysis processes have been studied in recent years, highlighting the process of fast pyrolysis of biomass to obtain bio-oil. The continuous fast pyrolysis, the most investigated and improved are the fluidized bed and ablative, but is being studied and developed other types in order to obtain Bio-oil a better quality, higher productivity, lower energy consumption, increased stability and process reliability and lower production cost. The stability of the product bio-oil is fundamental to designing consumer devices such as burners, engines and turbines. This study was motivated to produce Bio-oil, through the conversion of plant biomass or the use of its industrial and agricultural waste, presenting an alternative proposal for thermochemical pyrolysis process, taking advantage of particle dynamics in the rotating bed that favors the right gas-solid contact and heat transfer and mass. The pyrolyser designed to operate in a continuous process, a feeder containing two stages, a divisive system of biomass integrated with a tab of coal fines and a system of condensing steam pyrolytic. The prototype has been tested with sawdust, using a complete experimental design on two levels to investigate the sensitivity of factors: the process temperature, gas flow drag and spin speed compared to the mass yield of bio-oil. The best result was obtained in the condition of 570 oC, 25 Hz and 200 cm3/min, temperature being the parameter of greatest significance. The mass balance of the elementary stages presented in the order of 20% and 37% liquid pyrolytic carbon. We determined the properties of liquid and solid products of pyrolysis as density, viscosity, pH, PCI, and the composition characterized by chemical analysis, revealing the composition and properties of a Bio-oil.

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In this work, biodiesel was produced from castor oil that was a byproduct glycerin. The molar ratio between oil and alcohol, as well as the use of (KOH) catalyst to provide the chemical reaction is based on literature. The best results were obtained using 1 mol of castor oil (260g) to 3 moles of methyl alcohol (138g), using 1.0% KOH as catalyst at a temperature of 260 ° C and shaken at 120 rpm. The oil used was commercially available, the process involves the reaction of transesterification of a vegetable oil with methyl alcohol. The product of this reaction is an ester, biodiesel being the main product and the glycerin by-product which has undergone treatment for use as raw material for the production of allyl alcohol. The great advantage of the use of glycerin to obtain allyl alcohol is that its use eliminates the large amount of waste of the biodiesel and various forms of insult to the environment. The reactions for the formation of allyl alcohol was conducted from formic acid and glycerin in a ratio 1/1, at a temperature of 260oC in a heater blanket, being sprayed by a spiral condenser for a period of 2 hours and the product obtained contains mostly the allylic alcohol .. The monitoring of reactions was performed by UV-Visible Spectrophotometer: FTIR Fourier transform, the analysis showed that these changes occur spectrometer indicating the formation of the product allylic alcohol (prop-2-en-1-ol) in the presence of water, This alcohol was appointed Alcohol GL. The absorption bands confirms that the reaction was observed in (υ C = C) 1470 -1600 cm -1 and (υ CO), 3610-3670 attributed to C = C groups and OH respectively. The thermal analysis was carried out in a thermogravimetric analyzer SDT Q600, where the mass and temperature are displayed against time, that allows checking the approximate rate of heating. The innovative methodology developed in the laboratory (LABTAM, UFRN), was able to treat the glycerine produced by transesterification of castor oil and used as raw material for production of allyl alcohol, with a yield of 80%, of alcohol, the same is of great importance in the manufacture of polymers, pharmaceuticals, organic compounds, herbicides, pesticides and other chemicals

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The fast pyrolysis of lignocellulosic biomass is a thermochemical conversion process for production energy which have been very atratactive due to energetic use of its products: gas (CO, CO2, H2, CH4, etc.), liquid (bio-oil) and charcoal. The bio-oil is the main product of fast pyrolysis, and its final composition and characteristics is intrinsically related to quality of biomass (ash disposal, moisture, content of cellulose, hemicellulose and lignin) and efficiency removal of oxygen compounds that cause undesirable features such as increased viscosity, instability, corrosiveness and low calorific value. The oxygenates are originated in the conventional process of biomass pyrolysis, where the use of solid catalysts allows minimization of these products by improving the bio-oil quality. The present study aims to evaluate the products of catalytic pyrolysis of elephant grass (Pennisetum purpureum Schum) using solid catalysts as tungsten oxides, supported or not in mesoporous materials like MCM-41, derived silica from rice husk ash, aimed to reduce oxygenates produced in pyrolysis. The biomasss treatment by washing with heated water (CEL) or washing with acid solution (CELix) and application of tungsten catalysts on vapors from the pyrolysis process was designed to improve the pyrolysis products quality. Conventional and catalytic pyrolysis of biomass was performed in a micro-pyrolyzer, Py-5200, coupled to GC/MS. The synthesized catalysts were characterized by X ray diffraction, infrared spectroscopy, X ray fluorescence, temperature programmed reduction and thermogravimetric analysis. Kinetic studies applying the Flynn and Wall model were performed in order to evaluate the apparent activation energy of holoceluloce thermal decomposition on samples elephant grass (CE, CEL and CELix). The results show the effectiveness of the treatment process, reducing the ash content, and were also observed decrease in the apparent activation energy of these samples. The catalytic pyrolysis process converted most of the oxygenate componds in aromatics such as benzene, toluene, ethylbenzene, etc

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Many of hydrocarbon reserves existing in the world are formed by heavy oils (°API between 10 and 20). Moreover, several heavy oil fields are mature and, thus, offer great challenges for oil industry. Among the thermal methods used to recover these resources, steamflooding has been the main economically viable alternative. Latent heat carried by steam heats the reservoir, reducing oil viscosity and facilitating the production. This method has many variations and has been studied both theoretically and experimentally (in pilot projects and in full field applications). In order to increase oil recovery and reduce steam injection costs, the injection of alternative fluid has been used on three main ways: alternately, co-injected with steam and after steam injection interruption. The main objective of these injection systems is to reduce the amount of heat supplied to the reservoir, using cheaper fluids and maintaining the same oil production levels. This works discusses the use of carbon dioxide, nitrogen, methane and water as an alternative fluid to the steam. The analyzed parameters were oil recoveries and net cumulative oil productions. The reservoir simulation model corresponds to an oil reservoir of 100 m x 100 m x 28 m size, on a Cartesian coordinates system (x, y and z directions). It is a semi synthetic model with some reservoir data similar to those found in Brazilian Potiguar Basin. All studied cases were done using the simulator STARS from CMG (Computer Modelling Group, version 2009.10). It was found that waterflood after steam injection interruption achieved the highest net cumulative oil compared to other fluids injection. Moreover, it was observed that steam and alternative fluids, co-injected and alternately, did not present increase on profitability project compared with steamflooding

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A significant fraction of the hydrocarbon reserves in the world is formed by heavy oils. From the thermal methods used to recovery these resources, Steamflooding has been one of the main economically viable alternatives. In Brazil, this technology is widely used by Petrobras in Northeast fields. Latent heat carried by steam heats the oil in the reservoir, reducing its viscosity and facilitating the production. In the last years, an alternative more and more used by the oil industry to increase the efficiency of this mechanism has been the addition of solvents. When co-injected with steam, the vaporized solvent condenses in the cooler regions of the reservoir and mixes with the oil, creating a low viscosity zone between the steam and the heavy oil. The mobility of the displaced fluid is then improved, resulting in an increase of oil recovery. To better understand this improved oil recovery method and investigate its applicability in reservoirs with properties similar to those found in Potiguar Basin, a numerical study was done to analyze the influence of some operational parameters (steam injection rate, injected solvent volume and solvent type) on oil recovery. Simulations were performed in STARS ("Steam, Thermal, and Advanced Processes Reservoir Simulator"), a CMG ("Computer Modelling Group") program, version 2009.10. It was found that solvents addition to the injected steam not only anticipated the heated oil bank arrival to the producer well, but also increased the oil recovery. Lower cold water equivalent volumes were required to achieve the same oil recoveries from the models that injected only steam. Furthermore, much of the injected solvent was produced with the oil from the reservoir

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Durante as últimas décadas, as indústrias farmacêuticas têm despertado grande interesse em óleos vegetais e vários extratos de planta por causa da sua baixa toxicidade e alta biodegrabilidade. O óleo de copaíba (Cop) é usado in natura na medicina popular como anti-inflamatório e antimicrobiano para tratar várias doenças, tais como inflamação da garganta, úlceras e infecções urinárias e pulmonares. Emulsões são sistemas dispersos termodinamicamente instáveis que consistem em dispersões de gotículas microscópicas em outro líquido imiscível. O objetivo deste trabalho foi preparar diferentes emulsões de Cop, determinar o EHL crítico deste óleo e avaliar a sua estabilidade, além de realizar estudos comparativos entre diferentes métodos de construção de diagramas de fases. As emulsões foram preparadas pelo método de inversão de fases variando as proporções de EHL de 4,7 a 16,7. A estabilidade foi determinada por vários métodos e os diagramas de fases foram produzidos pelo método de titulação usando diferentes procedimentos de agitação. As emulsões a base de Cop com EHL entre 12,7 e 15,7 foram as mais estáveis. As emulsões apresentaram boa estabilidade em curto e longo prazo, aspecto leitoso e baixos valores de índice de cremagem. Diferentes sistemas coloidais foram produzidos a partir dos diagramas de fases dependendo do processo de agitação. Baseado nesses métodos, o valor determinado de EHL do Cop foi 14,8, as emulsões permaneceram estáveis por mais de um ano e estes resultados indicam que o estudo das emulsões de Cop pode ser um promissor veículo de liberação tópica de fármacos e ativos cosméticos

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Dans cette étude, j'ai eu comme objectif d'établir les connexions et/ou les non-connexions dans les discours journalistiques sur la modernité pédagogique, dans les journaux O Correio de Aracaju (Le Courrier d'Aracaju, Sergipe, Brésil) et O Século (Le Siècle, Portugal), dans la période 1910-1920. J'ai tout particulièrement cherché le dit dans les journaux, dans le sens foucaldien du terme, en continu dialogue avec d'autres auteurs, dans une perspective interdisciplinaire. J'ai tenté de répondre à mon interrogation initiale : quelles sont les connexions et non connexions que l'on pourrait établir entre l'École Moderne du Portugal et celle de Sergipe, au Brésil, en prenant comme source d'analyse les discours journalistiques dans des journaux des deux pays ? Á partir de ce questionnement, à travers un abordage historico-comparatif interculturel, j'ai soutenu la THÈSE que les discours journalistiques du Século et du Correio de Aracaju, bien qu'ils relèvent de genres journalistiques différents quant au niveau de développement de la presse, ont traduit une perception et une assimilation de la modernité pédagogique articulées à une même epistémè. Ainsi, ces discours ont émergé comme objets métis, dont la création s'est faite dans des interlocutions, échanges, impositions et débats dans un processus continu de communication interculturelle. La nature messianique de ces discours, dans le système d'idées républicain, traduisait le sens de la modernité pédagogique prétendue et diffusée par les textes qui exprimaient l'aspiration de rupture et de progrès, tant au Portugal que dans l'état brésilien de Sergipe. Il a également été possible de faire des approximations/comparaisons entre la dispute (article d'opinion), dans le Correio de Aracaju et l'enquête (interview et reportage), dans O Século et de souligner ainsi les connexions et/ou non-connexions présentes sur le thème de la modernité pédagogique dans les discours journalistiques

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Cette étude analyse La pratique pédagogique de l éducateur norte-rio-grandense Nestor dos Santos Lima, de 1910 a 1930, période ou se concentre son plus grand nombre de publications sur lês questions scolaires. Nous désirons comprendre de quelle forme cet intelectuel a contribué au développement du systeème d enseignement primaire à travers sés écrits sur lês principes et méthodes de l enseignement de la lecture et à l écriture, appliqués dans lês Groupes Scolaires de l État. Nestor Lima a joué um grand role dans la sociaété, à la tetê de fonctoins comme celle de La présidence de l Institut Historique e Geographique du Rio Grande do Norte (IHGRN), directeur de lÉcole Normale de Natal et du Dápartament d Education de État. Il a pulié de diverses oeuvres de caractere scolaire, comme lês Régiments Internes pour lês Groupes Scolaires, Écoles Isolées, Écoles Rudimentaires et Conseil d Education. Dans cette étude, nous mettons em évidence lês leçons de métodologique pour l enseignement de la lecture ET de évidence lês leçons de metodologie pour l enseignement de la lecture et de l ecriture, adresses aus eleves de lÉcole Normale de Natal, publiées dans la colonne Pádagogie du journal A República. Dans ces matièrs, nous observons que lês aspects qui composaient la pratique développe par Nestor Lima impliquaient lês questions Morales et civiques, la preocupation de la formation enseignante à l École Normale de Natal et le Célibat Pédagogique Féminin. Nous observons que la preocupations dês pratiques de lecture et lécriture sont presentes dans l oeuvre de cet éducateur comme legs important aux générations qui se succédent. Il est évident qu Il a cherché das sés productions une meilleure qualification dês enseignants pour que le niveau de l enseignement primaire puísse ainsi évoluer

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This research aims to analyze the concept of childhood in the dimension of educational practice, which is present in the regimental school and historically constructed power relations during the period 1910 to 1930, in Rio Grande do Norte. To contextualize this study, it is necessary to address the Bylaws of the School Groups (1915), the Internal Isolated Schools (1925) and Education Reform (1916). The expansion of education in the State, aiming at preparing the individual for the new capitalist social order was the concern of all governments of the first republic. During this period, the school is conceived as a privileged scenario of a set of practices aimed at disciplining the children, to explore, in some respects, the concept of childhood. Over time, this cocepção was constructed historically. In addition, the school receives children, which in the late nineteenth and early twentieth century, are inserted into an educational process in line with the state, embodied in laws, regulations and school discursive practices

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This research aims to analyze the intellectual practice of Luiz Antônio Ferreira Souto dos Santos Lima. This is done considering the author´s legacy related to the History of Education in Rio Grande do Norte/Brazil in the time span of 1910 to 1961. Thus, the research is grounded on assumptions that rely on the Cultural History field. The research also dealt with dialogues between the author and Chartier (1990), Elias (1994), Morais (2003; 2006), as well as Gondra (2003). For the bibliographical research the work dealt with a vast array of documents such as newspapers called A República and Diário do Natal, Pedagogium, Revista do ensino, as well as state laws and decrees These documents were obtained at the Historical and Geographical Institute in Rio Grande do Norte. The research also dealt with School Bylaws and a medical doctoral thesis called Mental Hygiene and Education that was written by Luiz Antônio dos Santos Lima. Other documents were obtained at the State´s Public Archive, such as the Book of Honor, Work Records, Reports and Minutes of the General Directorate of Public Instruction Meetings. It was possible to infer that professor Luiz Antônio dos Santos Lima was teacher at Grupo Escolar Augusto Severo, the Atheneu as well as some local grade schools. The professor had a broad role in society, in administrative positions such as the Presidency of the Association of Teachers of Rio Grande do Norte, as Grade School Director in the School of Pharmacy and the State Education Department. He was also a member of the Academy of Arts and a partner at Historical and Geographical Institute in Rio Grande do Norte. The professor has also concerned with issues related to teaching good habits such as feeding, grooming, discipline, game morals, temperance, smoking, sex education; all of which necessary for the formation of healthy children. He was an enthusiast of an intuitive method and teaching lessons through practice, that he considered key elements in education. It is seen that professor Luiz Antônio dos Santos Lima had presence in the State´s health education and that his ideals were line with the ideal of modernity of the early twentieth century

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This work addresses biodiesel by transesterification from the use of waste frying oil as a possible technological alternative for both reducing greenhouse gas emissions and by presenting themselves as an environmental call to designate a rational use of oil when no longer played in the environment to become renewable energy. It has proposed location of a residual oil and fat treatment plant to produce biodiesel, using models of Location and Routing for the improvement of routes. To achieve the goal, questionnaires were administered in establishments that use oil or vegetable fat in their productive activities in order to quantify the residue, to analyze actions and environmental perception of people who work directly with the residue on the destination you are being given to oil and fat used. It has indicated using of two single setup location, the method of Center of Gravity and the model of Ardalan, a geographical point that minimizes the costs of transporting waste to the treatment plant. Actions have been proposed for the improvement of collection routes this residue using the Routing Method of Scanning, as an illustration. The results demonstrated the lack of knowledge of the people who deal directly with large amounts of waste, on the environmental impacts caused by their incorrect disposal. The models used were uniform since point out to neighborhoods in similar regions. The neighborhoods of Lagoa Nova / Morro Branco (Ardalan) and Nova Descoberta (Center of Gravity) as ideal for the installation of treatment plant. However, it is suggested to be tested other models that take into account new variables than those used (supply of waste and the distance between points). The routing through the method of scanning has shown that it is possible, in a simple way to optimize routes in order to reduce distances and therefore the logistics costs in the collection of such waste. Introducing a route as a test to gather the twenty largest oil suppliers used in sample frying, using as a main factor time 8 hour of working shift every day

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This survey develops a study about the pro-environment behavior of a brazilian company of oil and gas sector, emphazing the Petróleo Brasileiro S/A PETROBRAS in its Unit of Business of Exploration and Production in the State of Rio Grande do Norte and Ceará − UN-RNCE. The work s development adopt the bibliographic research methodology with the descriptive exploratory analisys, with the purpouse of identifying related points with the knowledge and the analysed enterprise s staff conduct, by the aplication of the interview with a instrument of data colecting with closed variable questions from answers that varies from o to 10.The answers allowed us to know the employees knowledge about the related aspects of environmental responsability, knowing also the involvement of the employees with the politics of environmental managment that has been implemented in the operating area of the company. The research led us to an important verification of the pro-environmental behavior of the people interviewed. The results depends of a wise acting, not only inside the company, but also outside, where the results of this acting will be more perceived for the society. Finally, we conclude that the company has a politics of management with a great importance, emphasinzing that the employees are been in constant training about their behavior resulting in satisfaction