Currently, carbon is the preferred support material for platinum catalyst particles used in polymer electrolyte fuel cells (PEFCs). Carbon possesses qualities needed for a fuel cell catalyst: high surface area and conductivity, but is unacceptable as it is prone to oxidization by carbon dioxide in the fuel cell environment. Molybdenum Carbides is known to have the required conductivity. However, making Mo2C with sufficient surface area and with stabilized platinum remains a materials challenge. In this work a novel approach, a variation on the Aerosol-Through-Plasma (ATP) method was employed for making Mo2C with high surface area and stable supported platinum particles. An ammonium molybdate precursor was processed through different ATP conditions to generate the catalyst. These particles were then characterized using X-ray diffraction and SEM techniques in order to produce a support material with the highest concentration of Mo2C. Using the ideal conditions for the ATP, precursor was loaded with platinum and then processed through the ATP. This sample was then characterized using X-ray and SEM techniques to insure that the material was suitable prior to testing the electrochemical properties under PEFC operating conditions. The results were then compared to other leading support catalysis.

关键词：碳化物；燃料电池；钼；铵化合物；碳；二氧化碳

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The United States Department of Energy (DOE) Fissile Materials Disposition Program (FMDP) is pursuing disposal of surplus weapons-usable plutonium by reactor irradiation as the fissile constituent of MOX fuel. Lead test assemblies (LTAs) have been irradiated for approximately 36 months in Duke Energy's Catawba-1 nuclear power plant (NPP). Per the mixed oxide (MOX) fuel topical report, approved by the U.S. Nuclear Regulatory Commission (NRC), destructive post-irradiation examinations (PIEs) are to be performed on second cycle rods (irradiated to an average burnup of approximately 45 GWd/MTHM). The Radiochemical Analysis Group (RAG) at Oak Ridge National Laboratory (ORNL) is currently performing the detailed destructive post-irradiation examinations (PIE) on four of the mixed uranium and plutonium oxide fuel rods. The analytical process involves dissolution of designated fuel segments in a shielded hot cell for high precision quantification of select fission products and actinide isotopes employing isotope dilution mass spectrometry (IDMS) among other analyses. The hot cell dissolution protocol to include the collection and subsequent alkaline fusion digestion of the fuels acid resistant metallic particulates will be presented. Although the IDMS measurements of the fission products and actinide isotopes will not be completed by the time of the 51st INMM meeting, the setup and testing of the HPLC chromatographic separations in preparation for these measurements will be discussed.

关键词：混合氧化物燃料；钚氧化物；铀；锕系元素原子核

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The neutron radiography (NRAD) reactor is a 250 kW TRIGA (Training, Research, Isotopes, General Atomics) Mark IIa,b tank-type research reactor located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components.c The NRAD reactor is currently under the direction of the Battelle Energy Alliance (BEA) and is operated and maintained by the INL and Hot Cell Services Division. It is primarily used for neutron radiography analysis of both irradiated and unirradiated fuels and materials. Typical applications for examining the internal features of fuel elements and assemblies include fuel pellet separations, fuel central-void formation, pellet cracking, evidence of fuel melting, and material integrity under normal and extreme conditions. Examination of the behavior of large test loops and assemblies can also be performed. Due to the intense gamma activity of most irradiated specimens, the HFEF uses an indirect radiography, where a beam of neutrons passes through a specimen, strikes a gamma-insensitive metal foil (typically indium or dysprosium, for epithermal or thermal neutron spectra, respectively), and activates the foil. The foil can then be placed against a sheet of x-ray photographic film. X-rays from the metal foil then render an image on the film, which is then developed. While this method takes longer than the conventional direct method, the results eliminate gamma interference and are more detailed. Neutron tomography capabilities are being developed, where radiographs are obtained from different rotational angles and digitized to reconstruct cross-sections of a specimen. Direct radiography, such as Polaroid or track-etch radiography, and in-tank irradiations and/or experiments with small in-core samples can also be performed in the NRAD reactor.

关键词：核能反应；燃料电池；氢化物燃料

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Oxygen reduction reaction (ORR) is important in fuel cells. Although platinum nanoparticles can catalyse the ORR in an efficient way, the high cost of the platinum catalysts, together with its limited reserves in nature, has been shown to be the major 'showstopper' to mass market fuel cells for commercial applications. Following our earlier work on metal-free, nitrogen- doped carbon nanotubes (Gong, K.; Du, F.; Xia, Z.; Durstock, M.; Dai, L. Science 2009, 323, 760) and nitrogen-doped graphene sheets (Qu, L.; Liu, Y.; Baek, J.-B.; Dai, L. ACS Nano 2010, 4, 1321) as highly efficient ORR, we have developed in this project new metal-free and oxygen-free graphene materials by either edge-functionalization or ball milling as efficient electrocatalysts for ORR in fuel cells and other applications, including dye-sensitized solar cells (DSSCs).

关键词：催化剂；燃料电池；石墨烯；纳米科学与技术

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Energy availability and long term operation are key challenges for wireless sensor networks and for all the applications where the devices are battery operated. For this reason energy harvesting is becoming very important for powering ubiquitously deployed sensor networks and mobile electronics. One of most important goal for the next generation of power supply units for standalone embedded systems is to power nearly perpetually the devices when the scavenger is exposed to reasonable environmental energy conditions. However, due to the unpredictable nature of the environmental sources, prolonged lacks of energy intake usually happen. The last frontiers of perpetual operating systems is combining different energy harvesters in a single unit and using green energy supply with high energy density as micro hydrogen fuel cells. In this paper we introduce a Smart Power Unit (SPU) for embedded system which incorporates energy harvesters from sun and wind and uses hydrogen fuel cell as alternative energy storage. The power unit can work as a long-term battery or providing serial communication to exchange power information and to perform power management. In fact the core of the SPU is an ultra low power micro controller which is in charge to do the power activities such as Maximum Power Point Tracking for the harvesters, fuel cell activation, energy prediction, adaptive power management on board, battery monitoring and communications with powered systems. Experimental results and simulations shows the high efficiency (up to 90 %) of the power conversion subsystem. Finally a real deployment in a structural health monitoring site in Switzerland shows as the energy neutral condition is achieved on field.

关键词：氢电池；电动收割机；户外应用

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We deployed a 855 cm2 thin-film, single-junction gallium arsenide (GaAs) photovoltaic (PV) module outdoors. Due to its fundamentally different cell technology compared to silicon (Si), the module responds differently to outdoor conditions.

关键词：光伏电池；镓砷化物；薄膜；砷化镓太阳能电池

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The National Renewable Energy Laboratory (NREL), in association with the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), held a Biogas and Fuel Cells Workshop on June 11-13, 2012, in Golden, Colorado, to discuss biogas and waste-to-energy technologies for fuel cell applications. The meeting was spearheaded by the Fuel Cell Technologies Program in coordination with the Biomass Program. The overall objective was to identify opportunities for coupling renewable biomethane with highly efficient fuel cells to produce electricity; heat; combined heat and power (CHP); or combined heat, hydrogen and power (referred to as CHHP or trigeneration) for stationary or motive applications. The workshop focused on biogas sourced from wastewater treatment plants (WWTPs), landfills, and industrial facilities that generate or process large amounts of organic waste, including large biofuel production facilities (biorefineries).

关键词：生物质燃料；燃料电池；厌氧消化；沼气

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Active DMFCs require complicated balance of plant to ensure recirculation of unreacted methanol and internally produced water as well as venting of exhaust gases. An alternative approach is redesign of the fuel delivery system to accommodate concentrated methanol that is consumed entirely within the fuel cell, thus removing the need for recirculation. A specialized anodic porous structure was designed which the dual role of flowfield and diffusion medium for concentrated methanol. In addition, a highly hydrophobic gas diffusion media were used at the DMFC cathode to prevent water loss by promoting water back-diffusion to the anode. This internally dilutes the methanol and enables use of highly concentrated methanol. The anodic porous structure used in concert with the hydrophobic cathode diffusion medium led to gross fuel energy densities of the operating cell of ca. 845 W*hr/Lfuel and fuel utilization in excess of 70%. A small 2 cell stack was built and successfully operated to verify that the concept is scalable. The hydrophobicity of the cathode diffusion layer is of vital importance for this concept and research for improved materials that will reduce water loss even more is still ongoing using internal funds. The project also funded student research at Northeastern University and at Inter American University in Puerto Rico. This hardware based program complemented an IFDL modeling program sponsored by the DOE.

关键词：阴极；甲醇燃料电池；电动电池；电化学

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Energy availability and long term operation are key challenges for wireless sensor networks and for all the applications where the devices are battery operated. For this reason energy harvesting is becoming very important for powering ubiquitously deployed sensor networks and mobile electronics. One of most important goal for the next generation of power supply units for standalone embedded systems is to power nearly perpetually the devices when the scavenger is exposed to reasonable environmental energy conditions. However, due to the unpredictable nature of the environmental sources, prolonged lacks of energy intake usually happen. The last frontiers of perpetual operating systems is combining different energy harvesters in a single unit and using green energy supply with high energy density as micro hydrogen fuel cells. In this paper we introduce a Smart Power Unit (SPU) for embedded system which incorporates energy harvesters from sun and wind and uses hydrogen fuel cell as alternative energy storage. The power unit can work as a long-term battery or providing serial communication to exchange power information and to perform power management. In fact the core of the SPU is an ultra low power micro controller which is in charge to do the power activities such as Maximum Power Point Tracking for the harvesters, fuel cell activation, energy prediction, adaptive power management on board, battery monitoring and communications with powered systems. Experimental results and simulations shows the high efficiency (up to 90 %) of the power conversion subsystem. Finally a real deployment in a structural health monitoring site in Switzerland shows as the energy neutral condition is achieved on field.

关键词：氢燃料电池；能源供应；永久操作系统

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Polyelectrolytes, which are a macromolecule dissolved in water or polar solvent, have gained a wide attention among scientists and engineers for their wide application areas. Their different properties have allowed them to be used in many areas such as soap, body lotions, electrochromic devices, solid-state reference electrode systems, fuel cell exchange membranes, water treatment, waste treatment, paper production, corrosion protection, fuel cells, electrodialysis, contact lenses, membrane-based separations, drug delivery, and genetic science. Biocompatible polyelectrolytes are also utilized in biosensors and biomolecular recognition systems. Layer-by-layer (LbL) technique can be used to produce polyelectrolyte multilayer. Severe substrate such as gold, quartz, silicon, glass, plastic, stainless steel can be used in LbL technique. LbL technique is reproducible, cost-effective, and environmentally-friendly method. The characteristic properties of polyelectrolyte depend on the interaction between electrostatic forces. The degree of polymer charge can modify the electrostatic interactions. We examine the scaling theory according to Gennes et al. and Beurle and Nogovitsin in this chapter. After having discussed the scaling theory, we provide a basic introduction to properties of the neutron scattering and dynamic light scattering. In the end, we analyzed biopolymers and ionomers briefly. Polyelectrolytes (PEs) are generally denned as macromolecules, which when dissolved in water, dissociate to give highly charged polymeric molecules. As another definition, polyelectrolytes are polymers carrying either positively or negatively charged ionizable groups. These groups dissociate under appropriate conditions, and leaving ions on the chain and counter ions in the solution Examples of polyelectrolytes include polystyrene sulfonate, polyacrylic and polymethacrylic acids and their salts. DNA, proteins, nucleic acids, polysaccha-rides and other poly acids are given example to the natural polyelectrolytes. Polyelectrolytes are well known to play a vital role in nature and technology. PEs finds widespread use as solubilizing agents, phase separation agents, and rheo-logical property modifiers in daily life and technological applications. However, despite of their fundamental and practice importance, PEs systems still remain only poorly understood. This relates to the fact that their chemistry and physics are influenced by many controlling parameters, such as molecular weight, salt concentration, pH of the solution, etc.

关键词：聚电解质；高分子；天然聚电解质

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