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全面核禁试条约第三届全球次声监测工作研讨会于1997年8月25至28日在美国新墨西哥州西班牙式的古城圣菲举行.会议云集了中国、美国、法国、俄罗斯、阿根廷、澳大利亚等5大洲12个国家61位活跃在次声学科领域的研究人员、政府官员以及联合国临时技术秘书等要员,围绕着全球次声监测中的7个专题进行报告和讨论,它们依次为:欢声阵的设计和信号处理,次声阵性能和减噪设备;法国欢声监测系统,国际次声监测系统60个站网的能力模型,对流层风对长距离次声传播的影响,高空风对次声同性能的影响,渗透管的特性以及对次声监测的减噪作用,欢声减噪器;爆炸检测,声遥感技术对爆炸源能量的估计,小当量地下,地面和近地面爆炸远距离声传 相似文献
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Theoretical study of molecular hydrogen and spiltover hydrogen storage on two-dimensional covalent-organic frameworks 下载免费PDF全文
Molecular hydrogen and spiltover hydrogen storages on five two-dimensional (2D) covalent-organic frameworks (COFs) (PPy-COF, TP-COF, BTP-COF, COF-18 A, and HHTP-DPB COF) are investigated using the grand canonical Monte Carlo (GCMC) simulations and the density functional theory (DFT), respectively. The GCMC simulated results show that HHTP-DPB COF has the best performance for hydrogen storage, followed by BTP-COF, TP-COF, COF-18 A, and PPy-COE However, their adsorption amounts at room temperature are all too low to meet the uptake target set by US Department of Energy (US-DOE) and enable practical applications. The effects of pore size, surface area, and isosteric heat of hydrogen on adsorption amount are considered, which indicate that these three factors are all the important factors for determining the H2 adsorption amount. The chemisorptions of spiltover hydrogen atoms on these five COFs represented by the cluster models are investigated using the DFT method. The saturation cluster models are constructed by considering all possible adsorption sites for these cluster models. The average binding energy of a hydrogen atom and the saturation hydrogen storage density are calculated. The large average binding energy indicates that the spillover process may pro- ceed smoothly and reversibly. The saturation hydrogen storage density is much larger than the physisorption uptake of H2 molecules at 298 K and 100 bar (1 bar = 105 Pa), and is close to or exceeds the 2010 US-DOE target of 6 wt% for hydrogen storage. This suggests that the hydrogen storage capacities of these COFs by spillover may be significantly enhanced. Thus 2D COFs studied in this paper are suitable hydrogen storage media by spillover. 相似文献
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Design optimization of highly efficient spectrum-splitting and beam-concentrating diffractive optical element for lateral multijunction solar cells 下载免费PDF全文
Two improved algorithms are proposed to extend a diffractive optical element (DOE) to work under the broad spec- trum of sunlight. An optimum design has been found for the DOE, with a weighted average optical efficiency of about 6.8% better than that of the previous design. The optimization of designing high optical efficiency DOEs will pave the way for future designs of high-efficiency, low-cost lateral multijunction solar cells based on such a DOE. 相似文献
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美国能源部科学办公室出版的《Accelerators for America’s Future》中有这样一段描述:感恩节能吃上新鲜肥嫩的烤火鸡,别忘了感恩粒子加速器,因为几十年来美国食品加工商一直使用经粒子加速器辐照交联处理后的塑料薄膜--热收缩膜来包装火鸡。热收缩膜?听起来陌生,却已深深渗透到我们的生活之中。 相似文献
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Aggregation Behavior of Metal-Ethylene Complexes and Its Effect on Hydrogen Storage Capacity 下载免费PDF全文
The aggregation of Li, Ti decorated ethylene molecules and its effect on hydrogen storage capacity have been thoroughly studied using a first-principles calculation. The results indicate that the aggregation of C2H4-metal complexes substantially impacts on the hydrogen storage capacity. The aggregation of C2H4-Li reduces the hydrogen storage capacity greatly and makes the hydrogen storage capacity of C2H4-Li complexes hardly meet the demands of the U.S. DOE. The C2H4Ti2 dimers can uptake hydrogen as much as 10 wt%, which suggests that the C2H4Ti2 dimer can be a promising candidate for practical applications. 相似文献
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1989年,S.庞斯(stanley Pons)和M.弗雷斯曼(Martin Fleischmann)宣布发现了“冷聚变”.2004年12月1日,美国能源部召开了对“冷聚变”的评审会,评审15年来从低能核反应获得能源的进展.结论是:15年来没有更多的令人信服的证据. 相似文献
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