The partial substitution of Zr for La has been performed in order to ameliorate the electrochemical hydrogen storage performances of La-Mg-Ni based A2B7-type electrode alloys.The melt spinning technology was used to prepare the La0.75-xZrxMg0.25Ni3.2Co0.2Al0.1 (x=0,0.05,0.1,0.15,0.2) electrode alloys.The impacts of the melt spinning and the substituting La with Zr on the structures and the electrochemical hydrogen storage characteristics of the alloys were systemically investigated.The analysis of XRD and TEM reveals that the as-cast and spun alloys have a multiphase structure,composing of two main phases (La,Mg)2Ni7 and LaNi5 as well as a residual phase LaNi2.The electrochemical measurement indicates that both the substitution of Zr for La and the melt spinning ameliorate the electrochemical cycle stability of the alloys dramatically.Furthermore,the high rate discharge ability (HRD) of the as-spun (10 m/s) alloys notably declines with growing the amount of Zr substitution,while it first augments and then falls for the (x=0.1) alloy with rising the spinning rate.

关键词：A2B7型合金;代拉与锆，熔融纺丝;电化学特性

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This research project sought to develop a prototype hydrogen-based fuel cell system for ITS devices. The project investigated hydrogen storage capacities of the various candidate chemical hydride analogs; selected the most efficient of the candidates for energy storage based on volume, mass, and cost; developed a prototype system; and estimated the capital and operating cost for such a system. A hydrogen fuel cell combines hydrogen and oxygen to produce electricity, providing a clean, high-efficiency energy source that circumvents the problems associated with conventional batteries. A major drawback that limits its utility, however, is the use of heavy and bulky compressed metal cylinders as the source of hydrogen. The chemical-based hydrogen generation used in this project can provide a compact, atmospheric-pressure storage option for the controlled release of hydrogen. Many ITS-based applications can be envisaged with hydrogen-based fuel cells, such as alternating-traffic signs, directional signals, speed-limit signs, blinkers in series, warning blinkers, and backup power sources at traffic signals during power outages. This system is particularly attractive because many remote traffic signals on northern Minnesota roads lack access to a power grid, requiring the use of batteries that must be changed often, thus incurring maintenance costs.

关键词：制氢；燃料电池；成本缸筒电动电池；储能

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The Energy & Environmental Research Center (EERC) has continued the work of the National Center for Hydrogen Technology (NCHT) Program Year 6 Task 1.12 project to expose hydrogen separation membranes to coal-derived syngas. In this follow-on project, the EERC has exposed two membranes to coal-derived syngas produced in the pilot-scale transport reactor development unit (TRDU). Western Research Institute (WRI), with funding from the State of Wyoming Clean Coal Technology Program and the North Dakota Industrial Commission, contracted with the EERC to conduct testing of WRI's coal-upgrading/gasification technology for subbituminous and lignite coals in the EERC's TRDU. This gasifier fires nominally 200500 lb/hour of fuel and is the pilot-scale version of the full-scale gasifier currently being constructed in Kemper County, Mississippi. A slipstream of the syngas was used to demonstrate warm-gas cleanup and hydrogen separation using membrane technology. Two membranes were exposed to coal-derived syngas, and the impact of coal-derived impurities was evaluated. This report summarizes the performance of WRI's patent-pending coal upgrading/gasification technology in the EERC's TRDU and includes the results of the warmgas cleanup and hydrogen separation tests.

关键词：制氢；煤气化；清洁；燃料

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Computational modeling and experimental studies provide compelling evidence that displacement damage formation induced by fission neutrons and the 14.1 MeV neutrons representative of D-T fusion are quite similar. However, helium and hydrogen production levels with a D-T neutron energy spectrum are much higher. The impact of these gaseous transmutation products is a critical unresolved issue which is being addressed by combining numerical models and specialized ion and neutron irradiation experiments. Because of the uncertainties associated with both modeling and ion irradiation experiments, there is a clear need for an accessible irradiation facility that can provide near prototypic levels of helium and hydrogen. A modest range of He/dpa ratios is desirable to help calibrate and verify the modeling studies. The scientific understanding obtained would also enable more effective use of a future large-volume fusion engineering irradiation facility (such as IFMIF) when it becomes available. A conceptual level design for a fusion materials irradiation test station (FMITS) for installation at the Spallation Neutron Source (SNS) has been completed. Samples would be located within two horizontal tubes in front of the mercury target. For these specimen locations, the back-scattering neutron flux spectra should be close to the ITER fusion spectrum. The PKA spectra at the FMITS samples were also compared to those for ITER, and the results show good agreement. Material damage rates would be 1.65.5 dpa/yr for steel, and 1.83.4 dpa/yr for SiC.

关键词：中子源；热核聚变反应堆材料；氦；制氢

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The project was directed to discover new solid and liquid materials that use reversible catalytic hydrogenation as the mechanism for hydrogen capture and storage. After a short period of investigation of solid materials, the inherent advantages of storing and transporting hydrogen using liquid-phase materials focused our attention exclusively on organic liquid hydrogen carriers (liquid carriers). While liquid carriers such as decalin and methylcyclohexane were known in the literature, these carriers suffer from practical disadvantages such as the need for very high temperatures to release hydrogen from the carriers and difficult separation of the dehydrogenated carriers from the hydrogen. In this project, we were successful in using the prediction of reaction thermodynamics to discover liquid carriers that operate at temperatures up to 150 oC lower than the previously known carriers. The means for modifying the thermodynamics of liquid carriers involved the use of certain molecular structures and incorporation of elements other than carbon into the carrier structure. The temperature decrease due to the more favorable reaction thermodynamics results in less energy input to release hydrogen from the carriers. For the first time, the catalytic reaction required to release hydrogen from the carriers could be conducted with the carrier remaining in the liquid phase. This has the beneficial effect of providing a simple means to separate the hydrogen from the carrier.

关键词：氢气；吸附剂；碳；遏制；十氢萘；加氢

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An amorphous Mg85Ni15 melt-spun hydrogen storage alloy, processed by submersion in an aqueous solution of NH4 +, is able to absorb >5 wt.hydrogen at 473 K during the first hydrogenation cycle. The nanocrystalline microstructure formed during devitrification of the metallic glass is preserved by the lower required activation temperature of the NH4 +- treated material; and the kinetics of subsequent absorption/desorption cycles at 573 K are dramatically improved, compared to the as-spun material. DSC experiments and thermodynamic calculations demonstrate that the decreased crystallite size of the 473 K activated material lowers the hydride decomposition temperature by 20 K to 50 K, in contrast to a sample activated at 573 K. The NH4 +- treatment of a glassy alloy presented here provides a more practical approach to both forming a nanocrystalline material, and facilitating activation, compared to ball milling; requiring much less time and a more commercially scalable option.

关键词：贮氢合金;激活;金属玻璃氢原子;纳米晶微结构

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Theoretical studies of the possibility of forming ammonia electrochemically at ambient temperature and pressure are presented. Density functional theory calculations were used in combination with the computational standard hydrogen electrode to calculate the free energy profile for the reduction of N2 admolecules and N adatoms on several close-packed and stepped transition metal surfaces in contact with an acidic electrolyte. Trends in the catalytic activity were calculated for a range of transition metal surfaces and applied potentials under the assumption that the activation energy barrier scales with the free energy difference in each elementary step. The most active surfaces, on top of the volcano diagrams, are Mo, Fe, Rh, and Ru, but hydrogen gas formation will be a competing reaction reducing the faradaic efficiency for ammonia production. Since the early transition metal surfaces such as Sc, Y, Ti, and Zr bind N-adatoms more strongly than H-adatoms, a significant production of ammonia compared with hydrogen gas can be expected on those metal electrodes when a bias of - 1 V to - 1.5 V vs. SHE is applied. Defect-free surfaces of the early transition metals are catalytically more active than their stepped counterparts.

关键词：氢能；制氢；过渡金属；催化剂；吸附原子

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This work proposes a dynamic model of a three-phase catalytic slurry intensified continuous reactor.The model is simulated to describe the dynamic behaviors of the hydrogenation of o-cresol on Ni/SiO2 catalyst.The nominal operating point and the transient responses for different input perturbations are discussed.

关键词：加氢;集约化动态模拟;三相反应;连续反应器

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We analyse the transition state energies for 249 hydrogenation/dehydrogenation reactions of atoms and simple molecules over close-packed and stepped surfaces and nanoparticles of transition metals using Density Functional Theory. Linear energy scaling relations are observed for the transition state structures leading to transition state scaling relations for all the investigated reactions. With a suitable choice of reference systems the transition state scaling relations form a 15 universality class that can be approximated with one single linear relation describing the entire range of reactions over all types of surfaces and nanoclusters.

关键词：过渡元素；加氢；缩放；原子；化学反应

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IGCC coal-fired power plants show promise for environmentally-benign power generation. In these plants coal is gasified to syngas then processed in a water gas-shift (WGS) reactor to maximize the hydrogen/CO(sub 2) content. The gas stream can then be separated into a hydrogen rich stream for power generation and/or further purified for sale as a chemical and a CO(sub 2) rich stream for the purpose of carbon capture and storage (CCS). Today, the separation is accomplished using conventional absorption/desorption processes with post CO(sub 2) compression.

关键词：分子筛；膜氢原子；制氢；二氧化碳；煤气化

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