We investigated the activity and stability of n=(1, 2, 3) platinum layers supported on a number of rutile metal oxides (MO2; M=Ti, Sn, Ta, Nb, Hf and Zr). A suitable oxide support can alleviate the problem of carbon corrosion and platinum dissolution in Pt/C catalysts. Moreover, it can increase the activity of platinum if the interaction between the support and the metal is optimal. We found that both the activity and the stability depend on the number of platinum layers and, as expected, both converge toward platinum bulk values if the number of layers is increased. With use of a simple volcano curve for activity estimation, we found that the supported platinum layers could be active for the oxygen reduction reaction, with a few candidates possibly having an activity even greater than that of platinum. Furthermore, we established a correlation between stability and activity for supported platinum monolayers, which suggests that activity can be increased at the expense of stability and vice versa. Finally, the performance of the systems was evaluated against Pt(111) skins on Pt3X (X=Ni, Co, Fe, Ti, Sc and Y) alloys, which are the best catalysts known to date for the reaction.

关键词：环境与资源；燃料电池；质子交换膜（PEM）；金属氧化物

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A mathematical model of a Molten Carbonate Fuel Cell (MCFC) is shown.The model is used to simulate an experimental lab-stand single fuel cell unit measuring 55 cm2.The comparison of simulated data against the experimental results is shown and commented on.

关键词：环境与资源；燃料电池；数学模型；熔融碳酸盐

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In this work alkaline exchange membranes were prepared from the 3M perfluorinated ionomer by functionalization with two amine species that were further alkylated to quaternary ammonium cations. The methyl amine polymer was successfully quaternized to produce an ion exchange capacity (IEC) of 0.72 meq g-1, while the isopropyl amine did not quaternize resulting a negligible IEC of 0.02 meq g-1. Membrane swelling under a range of humidity conditions was characterized before and after thermal annealing through small angle x-ray scattering.

关键词：资源与环境；燃料电池；离子交换；傅立叶变换

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The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA Exploration program. The passive thermal management system relies on heat conduction within highly thermally conductive cooling plates to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack. Using the passive approach eliminates the need for a coolant pump and other cooling loop components within the fuel cell system which reduces mass and improves overall system reliability. Previous development demonstrated the performance of suitable highly thermally conductive cooling plates and integrated heat exchanger technology to collect the heat from the cooling plates (Ref. 1). The next step in the development of this passive thermal approach was the demonstration of the control of the heat removal process and the demonstration of the passive thermal control technology in actual fuel cell stacks. Tests were run with a simulated fuel cell stack passive thermal management system outfitted with passive cooling plates, an integrated heat exchanger and two types of cooling flow control valves. The tests were run to demonstrate the controllability of the passive thermal control approach. Finally, successful demonstrations of passive thermal control technology were conducted with fuel cell stacks from two fuel cell stack vendors.

关键词：环境与资源；燃料电池；冷却系统；传导传热；航空航天系统

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Extensive testing of the breadboard system was completed including baseline leak rate measurements. Several improvements were made to the system to permit stable, automated operation at 4 kilowatts, twice the previous power output, and the system was demonstrated at this power output. The first round of bench-top hydrogen recovery reactor media testing was completed. The supplier s procurement efforts for the final deliverable of the hermetically- sealed scroll compressors were underway.

关键词：环境与资源；燃料电池；能量密度；燃油系统；高效节能

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We have studied the effect of nanostructuring in Pt monolayer model electrocatalysts on a Rh(111) single-crystal substrate on the adsorption strength of chemisorbed species. In situ high energy resolution fluorescence detection x-ray absorption spectroscopy (HERFD XAS) at the Pt L3 edge reveals characteristic changes of the shape and intensity of the “white-line” due to chemisorption of atomic hydrogen (Had) at low potentials and oxygen-containing species (O/OHad) at high potentials. On a uniform, two-dimensional Pt monolayer grown by Pt evaporation in ultrahigh vacuum (UHV), we observe a significant destabilization of both Had and O/OHad due to strain and ligand effects induced by the underlying Rh(111) substrate. When Pt is deposited via a wetchemical route, by contrast, three-dimensional Pt islands are formed. In this case, strain and Rh ligand effects are balanced with higher local thickness of the Pt islands as well as higher defect density, shifting H and OH adsorption energies back towards pure Pt. Using density functional theory (DFT) we calculate O adsorption energies and corresponding local ORR activities for fcc threefold hollow sites with various local geometries that are present in the three-dimensional Pt islands.

关键词：环境与资源；燃料电池；化学吸附；密度泛函方法

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关键词：天然气；改革

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The results of hydrogenation of single walled carbon nanotubes (SWCNTs)-SnO2 composite, SWCNTs-WO3 composite, and SWCNTs-TiOs, are reported. The amount of hydrogen incorporated in the SWCNTs composites was determined and the dehydrogenation behavior was studied. The experimental evidences were provided by TEM, AFM, XRD, EDS, CHN and TG/TDS analyses.

关键词：环境与资源；燃料电池；能源储存系统；单壁碳纳米管

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为支持水电行业发展，统一和规范大型水电企业增值税政策，3月12日，财政部下发《关于大型水电企业增值税政策的通知》（简称《通知》）。《通知》称，装机容量超过100万千瓦的水力发电站（含抽水蓄能电站）销售自产电力产品，自2013年1月1日至2015年12月31日，对其增值税实际税负超过8%的部分实行即征即退政策；自2016年1月1日至2017年12月31日，对其增值税实际税负超过12%的部分实行即征即退政策。

关键词：电力行业；要闻综述

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提出了一种基于粒子群优化BP神经网络风电机组齿轮箱故障诊断方法.粒子群算法不需要计算梯度,可以兼顾全局寻优和局部寻优.利用粒子群算法对BP网络权值和偏置进行优化,减少了BP神经网络算法陷入局部最优解的风险,提高了神经网络的训练效率,加快了网络的收敛速度.考虑风电齿轮箱振动信号的不确定性、非平稳性和复杂性,提取功率谱熵、小波熵、峭度、偏度、关联维数和盒维数作为故障特征.经测试,算法诊断结果正确,表明了PSO优化BP神经网络用于风电机组齿轮箱故障诊断的有效性和实用性.

关键词：风电机组；齿轮箱；故障诊断；粒子群优化算法；BP神经网络；故障特征

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