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Reformed Methanol Fuel Cell
Reformed Methanol Fuel Cell (RMFC) or Indirect Methanol Fuel Cell (IMFC) systems are a subcategory of proton-exchange fuel cells where, the fuel, methanol (CH3OH), is reformed, before being fed into the fuel cell. RMFC systems offer advantages over direct methanol fuel cell (DMFC) systems including higher efficiency, smaller cell stacks, less requirement on methanol purity, no water management, better operation at low temperatures, and storage at sub-zero temperatures because methanol is a liquid from -97.0 °C to 64.7 °C (-142.6 °F to 148.5 °F) and as there is no liquid methanol-water mixture in the cells which can destroy the membrane of DMFC in case of frost. The reason for the high efficiency of RMFC in contrast to DMFC is that hydrogen containing gas is fed to the fuel cell stack instead of methanol and overpotential (power loss for catalytic conversion) on anode is much lower for hydrogen than for methanol. The tradeoff is that RMFC systems operate at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reformed Methanol Fuel Cell (block Diagram)
Reformed Methanol Fuel Cell (RMFC) or Indirect Methanol Fuel Cell (IMFC) systems are a subcategory of proton-exchange fuel cells where, the fuel, methanol (CH3OH), is reformed, before being fed into the fuel cell. RMFC systems offer advantages over direct methanol fuel cell (DMFC) systems including higher efficiency, smaller cell stacks, less requirement on methanol purity, no water management, better operation at low temperatures, and storage at sub-zero temperatures because methanol is a liquid from -97.0 °C to 64.7 °C (-142.6 °F to 148.5 °F) and as there is no liquid methanol-water mixture in the cells which can destroy the membrane of DMFC in case of frost. The reason for the high efficiency of RMFC in contrast to DMFC is that hydrogen containing gas is fed to the fuel cell stack instead of methanol and overpotential (power loss for catalytic conversion) on anode is much lower for hydrogen than for methanol. The tradeoff is that RMFC systems operate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preferential Oxidation
PROX is an acronym for PReferential OXidation, and refers to the preferential oxidation of a carbon monoxide in a gas mixture by a catalyst. It is intended to remove trace amounts of CO from H2/CO/CO2 mixtures produced by steam reforming and water-gas shift. An ideal PROX catalyst preferentially oxidizes carbon monoxide (CO) using a heterogeneous catalyst placed upon a ceramic support. Catalysts include metals such as platinum, platinum/iron, platinum/ruthenium, gold nanoparticles as well as novel copper oxide/ceramic conglomerate catalysts. Motivation This reaction is a considerable subject area of research with implications for fuel cell design. Its main utility lies in the removal of carbon monoxide (CO) from the fuel cell's feed gas. CO poisons the catalyst of most low-temperature fuel cells. Carbon monoxide is often produced as a by-product from steam reforming of hydrocarbons, which produces hydrogen and CO. It is possible to consume most of the CO by reacting it with ste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Army Communications-Electronics Research, Development And Engineering Center
The Combat Capabilities Development Command (CCDC) C5ISR Center, formerly the Communications-Electronics RD&E Center (CERDEC), is the United States Army information technologies and integrated systems center. CCDC C5ISR Center is headquartered at Aberdeen Proving Ground in Maryland, with activities at Fort Belvoir in Virginia and Joint Base McGuire-Dix-Lakehurst in New Jersey. As one of the 10 organizations that make up the Combat Capabilities Development Command The Combat Capabilities Development Command, (DEVCOM, aka CCDC) (formerly the United States Army Research, Development, and Engineering Command (RDECOM)) is a subordinate command of the U.S. Army Futures Command. RDECOM was tasked with "creating, ..., a subordinate organization of the Army Futures Command, CCDC C5ISR Centers supplies Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance and Reconnaissance ( C5ISR) capabilities, technologies and integrated solutions for the Soldier. Core com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fan (implement)
A handheld fan, or simply hand fan, is any broad, flat surface that is waved back-and-forth to create an airflow. Generally, purpose-made handheld fans are folding fans, which are shaped like a sector of a circle and made of a thin material (such as paper or feathers) mounted on slats which revolve around a pivot so that it can be closed when not in use. Hand fans were used before mechanical fans were invented. On human skin, the airflow from handfans increases evaporation which has a cooling effect due to the latent heat of evaporation of water. It also increases heat convection by displacing the warmer air produced by body heat that surrounds the skin, which has an additional cooling effect, provided that the ambient air temperature is lower than the skin temperature – which is typically about . Fans are convenient to carry around, especially folding fans. Next to the folding fan, the rigid hand screen fan was also a highly decorative and desired object among the higher cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Compressor
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor. Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe. The main distinction is that the focus of a compressor is to change the density or volume of the fluid, which is mostly only achievable on gases. Gases are compressible, while liquids are relatively incompressible, so compressors are rarely used for liquids. The main action of a pump is to pressurize and transport liquids. Many compressors can be staged, that is, the fluid is compressed several times in steps or stages, to increase discharge pressure. Often, the second stage is physically smaller than the primary stage, to accommodate the already compressed gas without reducing its pressure. Each stage further compresses the gas and increases its pressure and also temperature (if inter cooling between stages i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel Pump (engine)
A fuel pump is a component in motor vehicles that transfers liquid from the fuel tank to the carburetor or fuel injector of the internal combustion engine. Carbureted engines often use low pressure mechanical pumps that are mounted outside the fuel tank, whereas fuel injected engines often use electric fuel pumps that are mounted inside the fuel tank (and some fuel injected engines have two fuel pumps: one low pressure/high volume supply pump in the tank and one high pressure/low volume pump on or near the engine). Fuel pressure needs to be within certain specifications for the engine to run correctly. If the fuel pressure is too high, the engine will run rough and rich, not combusting all of the fuel being pumped making the engine inefficient and a pollutant. If the pressure is too low, the engine may run lean, misfire, or stall. A fuel pump is not necessarily required for the engine to function. The low-pressure fuel needed by a carbureted engine can be supplied simply by mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condenser (heat Transfer)
In systems involving heat transfer, a condenser is a heat exchanger used to condense a gaseous substance into a liquid state through cooling. In so doing, the latent heat is released by the substance and transferred to the surrounding environment. Condensers are used for efficient heat rejection in many industrial systems. Condensers can be made according to numerous designs, and come in many sizes ranging from rather small (hand-held) to very large (industrial-scale units used in plant processes). For example, a refrigerator uses a condenser to get rid of heat extracted from the interior of the unit to the outside air. Condensers are used in air conditioning, industrial chemical processes such as distillation, steam power plants and other heat-exchange systems. Use of cooling water or surrounding air as the coolant is common in many condensers. History The earliest laboratory condenser, a " Gegenstromkühler" (counter-flow condenser), was invented in 1771 by the Swedish-German ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platinum
Platinum is a chemical element with the symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish , a diminutive of "silver". Platinum is a member of the platinum group of elements and group 10 of the periodic table of elements. It has six naturally occurring isotopes. It is one of the rarer elements in Earth's crust, with an average abundance of approximately 5 μg/kg. It occurs in some nickel and copper ores along with some native deposits, mostly in South Africa, which accounts for ~80% of the world production. Because of its scarcity in Earth's crust, only a few hundred tonnes are produced annually, and given its important uses, it is highly valuable and is a major precious metal commodity. Platinum is one of the least reactive metals. It has remarkable resistance to corrosion, even at high temperatures, and is therefore considered a noble metal. Consequent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalytic Combustion
Catalytic combustion is a chemical process which uses a catalyst to speed desired oxidation reactions of fuel and so reduce the formation of undesired products, especially pollutant nitrogen oxide gases (NOx) far below what can be achieved without catalysts. The process was discovered in the 1950s by Catalytic Combustion LLC. Chemical process Catalysts may be used to control combustion reactions in the following ways: # fuel preparation, such as splitting long molecules into shorter ones; # fuel oxidation to release heat energy; # the destruction of pollutant gases in the exhaust. Technology Catalytic combustion was developed by Norb Ruff in the 1950s.Worthy, Sharon. Bio-Medicine: Connecticut chemist receives award for cleaner air technology'. 23 June 2003. Retrieved 31 October 2012. He founded Catalytic Combustion LLC in the 1950s where he created and patented the first metal catalyst. Other early work was carried out by researchers at Acurex, Westinghouse, NASA and the United ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalytic Combustion Afterburner
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
