939 resultados para Fuel Qualification
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The original objective of this work was to provide a simple generator w.hich would produce hydrogen torLfuel-cell feed and which could be operated under remote or northern conditions. A secondary objective was to maximize the yield of hydrogen and carbon monoxide from available feed-stocks. A search of the patent literature has indicated that the concept of a small Wulff-type generator is essentially sound and that hydrogen may be recovered from a wide variety of hydrocarbon feed-stocks. A simple experimental set-up has been devised, patterned after ~~t originally used by R. G. Wulff for producing acetylene. This provides a supply of feed-stock, with or Without a carrier gas, which may be passed directly through a heated tube, which may contain a catalyst. A suitable procedure has been devised for analysi~ effluent gases for hydrogen, oxygen, nitrogen, methane and carbon monoxide by gas chromatography with the column packed with .Molecular .:>ieve .5 4. Athanol with air a.s carrier gas and at the same time as oxidant o was thermolyzed at temperatures in the ra~e 700-1100 C, with or Wi~lout catalyst. Methanol with or without nitrogen as a carrier gas was also cracked with the same type of reactor refractory tube, but the temperature range was lower t down to ,300 " C when a catalyst was used. The problems of converting methane to hydrogen and carbon monoxide effiCiently, using air and/or water as oxidants were also studied.
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This qualitative study investigated the experiences of immigrant professional engineers in Canada, 81% of whom are unable to secure employment in their field despite arriving under the auspices of the Canadian governments skilled workers program. The study sought to identify factors that impede such qualified engineers opportunities within the Canadian job market. Because global economic competition demands that qualified professionals contribute to technological innovation, Canada must develop transitional programs that acknowledge credentials and prior work experience in order to address the underutilization of these qualified professionals and allow immigrant engineers to gain employment within their field. To this end, the study examined personal narratives of immigrant engineers who have experienced unemployment despite high levels of educational attainment, and circumstances that contribute to immigrant engineers unemployed status. The paper presents a discussion and recommendations for future research in the area of qualification without suitable employment.
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Province of Ontario Patent issued to Cyrus Dean of St. Catharines for a machine for effecting more perfect combustion of fuel in the furnaces of locomotives. This patent was listed in the Records Office of the Registrar General of Canada in Lib. JE, folio 361. This patent is accompanied by a 36 cm. x 57 cm. detailed sketch and explanation of the machine. [Samuel D. Woodruff was the assignee of Cyrus Dean in a in a patent for a rotary washing machine in November of 1869 according to The Commissioners of Patents' Journal by the Great Britain Patent Office], March 23, 1870.
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Tesis (Maestra en Ciencias de la Ingeniera Elctrica con Especialidad en Control Automtico) UANL, 2012.
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Article publi avec l'autorisation de la Chambre des notaires du Qubec
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La qualification est centrale l'activit du juriste. Les rgles de droit positif ne reoivent application qu'au moment o les faits reoivent une certaine qualification. Cette ralit prend une dimension particulire face au contrat, lequel est l'objet de multiples dispositions lgislatives. Le lgislateur a cru bon au fil du temps, de rglementer diverses formes contractuelles, les contrats nomms. On oppose ceux-ci les contrats innomms, pure cration extra-lgislative. La dtermination de la nature du contrat passe par un processus de qualification indpendant de notions connexes et qui doit s'loigner d'une mthode intuitive. La qualification du contrat passera principalement par lanalyse des obligations en vue d'identifier l'obligation fondamentale ou la prestation caractristique du contrat. Il s'agit d'une analyse qu'on veut objective. Les parties auront peu d'influence sur la qualification qui sera ultrieurement donne leur contrat, celle-ci tant une question de droit en principe rserve au juge. Le juriste tentera d'abord de lier le contrat aux modles nomms connus et prvus par le lgislateur, soit en lui donnant un seul nom ou en reconnaissant la nature mixte de la convention. Dans l'ventualit o ces tentatives ne sont pas concluantes, une qualification innomme devra tre choisie. La distinction entre les diffrentes qualifications possible sera ralise en fonction de la hirarchie des obligations au contrat et par l'cart de celle-ci avec les modles connus.
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Thse ralise en cotutelle avec l'cole des hautes tudes en sciences sociales
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L'obligation de scurit informationnelle - c'est--dire la tche qui incombe aux entreprises d'assurer l'intgrit, la confidentialit et la disponibilit de l'information dcoule, tant en droit qubcois que dans une majorit de juridictions occidentales, d'une srie de dispositions lgislatives imposant non pas l'adoption de comportements ou l'utilisation de technologies ou de procds identifiables, mais bien l'implantation de mesures de scurit raisonnables , adquates , ou suffisantes . Or, dans un domaine aussi embryonnaire et complexe que celui de la scurit informationnelle, domaine dans lequel les solutions disponibles sont multiples et o la jurisprudence est parse, comment une entreprise peut-elle jauger avec justesse l'tendue de son obligation? Bref, comment tablir ce que ferait une entreprise raisonnablement prudente et diligente dans un domaine o il n'existe actuellement aucune balise lgislative, jurisprudentielle ou mme coutumire permettant de fixer avec justesse le niveau de diligence impos par le lgislateur? L'absence de scurit juridique offerte par une telle situation est patente et ncessite une reconfiguration du cadre opratoire de l'obligation de scurit informationnelle afin d'en identifier les composantes et les objectifs. Cet exercice passera par la redfinition de l'obligation de scurit informationnelle comme obligation de rduire les risques qui guettent l'information un niveau socialement acceptable. En effet, la scurit pouvant tre dfinie comme tant la gestion du risque, c'est donc le risque qui rside au cur de cette obligation. Or, en analysant les risques qui guettent un systme, soit en analysant les menaces qui visent exploiter ses vulnrabilits, il est possible d'tablir quelles contre-mesures s'avrent utiles et les cots associs leur mise en uvre. Par la suite, il devient envisageable, en recourant la dfinition conomique de la ngligence et en prenant compte des probabilits de brches de scurit et des dommages escompts, d'tablir les sommes optimales investir dans l'achat, l'entretien et la mise jour de ces contre-mesures. Une telle analyse permet ainsi de quantifier avec un certain degr de prcision l'tendue de l'obligation de scurit informationnelle en offrant aux entreprises un outil s'inspirant de donnes matrielles auxquelles elles ont librement accs et s'intgrant aisment dans le contexte juridique contemporain.
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A stand-alone power system is an autonomous system that supplies electricity to the user load without being connected to the electric grid. This kind of decentralized system is frequently located in remote and inaccessible areas. It is essential for about one third of the world population which are living in developed or isolated regions and have no access to an electricity utility grid. The most people live in remote and rural areas, with low population density, lacking even the basic infrastructure. The utility grid extension to these locations is not a cost effective option and sometimes technically not feasible. The purpose of this thesis is the modelling and simulation of a stand-alone hybrid power system, referred to as hydrogen Photovoltaic-Fuel Cell (PVFC) hybrid system. It couples a photovoltaic generator (PV), an alkaline water electrolyser, a storage gas tank, a proton exchange membrane fuel cell (PEMFC), and power conditioning units (PCU) to give different system topologies. The system is intended to be an environmentally friendly solution since it tries maximising the use of a renewable energy source. Electricity is produced by a PV generator to meet the requirements of a user load. Whenever there is enough solar radiation, the user load can be powered totally by the PV electricity. During periods of low solar radiation, auxiliary electricity is required. An alkaline high pressure water electrolyser is powered by the excess energy from the PV generator to produce hydrogen and oxygen at a pressure of maximum 30bar. Gases are stored without compression for short- (hourly or daily) and long- (seasonal) term. A proton exchange membrane (PEM) fuel cell is used to keep the systems reliability at the same level as for the conventional system while decreasing the environmental impact of the whole system. The PEM fuel cell consumes gases which are produced by an electrolyser to meet the user load demand when the PV generator energy is deficient, so that it works as an auxiliary generator. Power conditioning units are appropriate for the conversion and dispatch the energy between the components of the system. No batteries are used in this system since they represent the weakest when used in PV systems due to their need for sophisticated control and their short lifetime. The model library, ISET Alternative Power Library (ISET-APL), is designed by the Institute of Solar Energy supply Technology (ISET) and used for the simulation of the hybrid system. The physical, analytical and/or empirical equations of each component are programmed and implemented separately in this library for the simulation software program Simplorer by C++ language. The model parameters are derived from manufacturers performance data sheets or measurements obtained from literature. The identification and validation of the major hydrogen PVFC hybrid system component models are evaluated according to the measured data of the components, from the manufacturers data sheet or from actual system operation. Then, the overall system is simulated, at intervals of one hour each, by using solar radiation as the primary energy input and hydrogen as energy storage for one year operation. A comparison between different topologies, such as DC or AC coupled systems, is carried out on the basis of energy point of view at two locations with different geographical latitudes, in Kassel/Germany (Europe) and in Cairo/Egypt (North Africa). The main conclusion in this work is that the simulation method of the system study under different conditions could successfully be used to give good visualization and comparison between those topologies for the overall performance of the system. The operational performance of the system is not only depending on component efficiency but also on system design and consumption behaviour. The worst case of this system is the low efficiency of the storage subsystem made of the electrolyser, the gas storage tank, and the fuel cell as it is around 25-34% at Cairo and 29-37% at Kassel. Therefore, the research for this system should be concentrated in the subsystem components development especially the fuel cell.
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Energy production from biomass and the conservation of ecologically valuable grassland habitats are two important issues of agriculture today. The combination of a bioenergy production, which minimises environmental impacts and competition with food production for land with a conversion of semi-natural grasslands through new utilization alternatives for the biomass, led to the development of the IFBB process. Its basic principle is the separation of biomass into a liquid fraction (press fluid, PF) for the production of electric and thermal energy after anaerobic digestion to biogas and a solid fraction (press cake, PC) for the production of thermal energy through combustion. This study was undertaken to explore mass and energy flows as well as quality aspects of energy carriers within the IFBB process and determine their dependency on biomass-related and technical parameters. Two experiments were conducted, in which biomass from semi-natural grassland was conserved as silage and subjected to a hydrothermal conditioning and a subsequent mechanical dehydration with a screw press. Methane yield of the PF and the untreated silage was determined in anaerobic digestion experiments in batch fermenters at 37C with a fermentation time of 13-15 and 27-35 days for the PF and the silage, respectively. Concentrations of dry matter (DM), ash, crude protein (CP), crude fibre (CF), ether extract (EE), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent ligning (ADL) and elements (K, Mg, Ca, Cl, N, S, P, C, H, N) were determined in the untreated biomass and the PC. Higher heating value (HHV) and ash softening temperature (AST) were calculated based on elemental concentration. Chemical composition of the PF and mass flows of all plant compounds into the PF were calculated. In the first experiment, biomass from five different semi-natural grassland swards (Arrhenaterion I and II, Caricion fuscae, Filipendulion ulmariae, Polygono-Trisetion) was harvested at one late sampling (19 July or 31 August) and ensiled. Each silage was subjected to three different temperature treatments (5C, 60C, 80C) during hydrothermal conditioning. Based on observed methane yields and HHV as energy output parameters as well as literature-based and observed energy input parameters, energy and green house gas (GHG) balances were calculated for IFBB and two reference conversion processes, whole-crop digestion of untreated silage (WCD) and combustion of hay (CH). In the second experiment, biomass from one single semi-natural grassland sward (Arrhenaterion) was harvested at eight consecutive dates (27/04, 02/05, 09/05, 16/05, 24/05, 31/05, 11/06, 21/06) and ensiled. Each silage was subjected to six different treatments (no hydrothermal conditioning and hydrothermal conditioning at 10C, 30C, 50C, 70C, 90C). Energy balance was calculated for IFBB and WCD. Multiple regression models were developed to predict mass flows, concentrations of elements in the PC, concentration of organic compounds in the PF and energy conversion efficiency of the IFBB process from temperature of hydrothermal conditioning as well as NDF and DM concentration in the silage. Results showed a relative reduction of ash and all elements detrimental for combustion in the PC compared to the untreated biomass of 20-90%. Reduction was highest for K and Cl and lowest for N. HHV of PC and untreated biomass were in a comparable range (17.8-19.5 MJ kg-1 DM), but AST of PC was higher (1156-1254C). Methane yields of PF were higher compared to those of WCD when the biomass was harvested late (end of May and later) and in a comparable range when the biomass was harvested early and ranged from 332 to 458 LN kg-1 VS. Regarding energy and GHG balances, IFBB, with a net energy yield of 11.9-14.1 MWh ha-1, a conversion efficiency of 0.43-0.51, and GHG mitigation of 3.6-4.4 t CO2eq ha-1, performed better than WCD, but worse than CH. WCD produces thermal and electric energy with low efficiency, CH produces only thermal energy with a low quality solid fuel with high efficiency, IFBB produces thermal and electric energy with a solid fuel of high quality with medium efficiency. Regression models were able to predict target parameters with high accuracy (R2=0.70-0.99). The influence of increasing temperature of hydrothermal conditioning was an increase of mass flows, a decrease of element concentrations in the PC and a differing effect on energy conversion efficiency. The influence of increasing NDF concentration of the silage was a differing effect on mass flows, a decrease of element concentrations in the PC and an increase of energy conversion efficiency. The influence of increasing DM concentration of the silage was a decrease of mass flows, an increase of element concentrations in the PC and an increase of energy conversion efficiency. Based on the models an optimised IFBB process would be obtained with a medium temperature of hydrothermal conditioning (50C), high NDF concentrations in the silage and medium DM concentrations of the silage.
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Existing fuel taxes play a major role in determining the welfare effects of exempting the transportation sector from measures to control greenhouse gases. To study this phenomenon we modify the MIT Emissions Prediction and Policy Analysis (EPPA) model to disaggregate the household transportation sector. This improvement requires an extension of the GTAP data set that underlies the model. The revised and extended facility is then used to compare economic costs of cap-and-trade systems differentiated by sector, focusing on two regions: the USA where the fuel taxes are low, and Europe where the fuel taxes are high. We find that the interplay between carbon policies and pre-existing taxes leads to different results in these regions: in the USA exemption of transport from such a system would increase the welfare cost of achieving a national emissions target, while in Europe such exemptions will correct pre-existing distortions and reduce the cost.
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Resumen tomado de la publicacin
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Presenta una experiencia pedaggica, basada en la catstrofe del Prestige, llevada a cabo con los alumnos de quinto del CEIP Milladoiro, del municipio de Malpica de Bergantios (A Corua) que result perjudicado por el fuel. Por medio de esta actividad, los alumnos intentan entender el mundo. Para ello, leen peridicos, siguen el da a da del suceso y, sobre todo, expresan los sentimientos que les produce encontrar animales muertos en la playa o ver los barcos de los pescadores amarrados.
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Resumen basado en el de la publicaci??n
