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本文基于分子聚集理论和硬球引力场模型应用分子热力学方法导出CS-vdW状态方程,应用上述方程计算了CO2气-液和气-固平衡相的饱和态下pVT性质.取得了很满意的结果.本方法的优点是使用简便,可供工程计算使用. 相似文献
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Coverage control is a fundamental problem in sensor networks, which has been explored thoroughly based on a traditional scalar sensing model. However, camera sensors are different from traditional scalar sensors as different cameras from different positions can form distinct views of the target. Hence, Target size and geometric structure of camera nodes can greatly influence the surveillance ability of a camera network. In view of this, a novel observation reliability model of a camera network is proposed, and relationship between surveillance ability and observing reliability for the target is studied. On the basis, a camera network coverage model which considers about obstacles and interesting area of the environment is investigated, and optimized by dynamic planning method. Simulation results show that our method can effectively improve the target capture rate of the network and also we can observe the target from a better view. 相似文献
996.
采用超声处理辅助浸渍法制备了多壁碳纳米管负载的Cu-Co复合氧化物催化剂. 利用XRD、TEM、H2-TPR、XPS和Raman光谱等表征了催化剂的结构性质. 在Cu和Co氧化物以及金属氧化物与碳纳米管载体间存在强相互作用. 催化剂在富氢气氛中CO催化消除反应中,与单一Cu或Co催化剂相比,Cu-Co复合氧化物催化剂表现出独特的反应特性,特别是在较高反应温度下可同时结合CO优先氧化和CO甲烷化的反应途径来实现高效CO消除. 当Cu/Co比为1/8时活性最优,可以实现在150~250 o和高反应空速 (120 L/(h·g))富氢气氛中CO的完全消除. 相似文献
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Enhancing the efficiency of TiO2–perovskite heterojunction solar cell via evaporating Cs2CO3 on TiO2
In a TiO2–perovskite heterojunction solar cell (TiO2–PHSC), besides the perovskite CH3NH3PbX3, TiO2 as one side of the TiO2/CH3NH3PbX3 heterojunction also plays an important role in the photovoltaic effect. In order to improve the performance of the TiO2–PHSC with the structure of glass/FTO/compact TiO2/mesoporous TiO2/CH3NH3PbI3–xClx /poly‐TPD (poly(N,N ′‐bis(4‐butylphenyl)‐N,N ′‐bis(phenyl)benzidine))/Au, a 2 nanometer thick Cs2CO3 layer is thermally evaporated on the mesoporous TiO2 layer. The short‐circuit current density (Jsc) raises from 17.7 mA cm–2 to 18.9 mA cm–2, the open‐circuit voltage (Voc) from 0.81 V to 0.87 V, and the fill factor (FF) from 55.2% to 67.3%; as a result, the power conservation efficiency (PCE) increases from 8.0% to 11.1% under AM 1.5G solar illumination (100 mW cm–2). Moreover, in a TiO2–PHSC free of mesoporous TiO2, where Cs2CO3 is evaporated on the compact TiO2 layer, the Jsc, Voc, FF and PCE values increase from 16.0 mA cm–2, 0.83 V, 50.8% and 6.7% to 17.9 mA cm–2, 0.90 V, 59.3%, and 9.5%, respectively. The reasons of the PCE increase for either the first kind of TiO2–PHSC or the mesoporous‐TiO2‐free TiO2–PHSC with a nanometer‐thick Cs2CO3 layer on mesoporous TiO2 or compact TiO2 are discussed. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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A series of semicrystalline microcellular materials were prepared by the foaming technology using supercritical fluids. The distribution of multi‐size microcellulars and multi‐layer arrangement was observed by scanning electronic microscopy. By controlling the foaming condition accurately, the alternated arrangement of variable in cellular size may be tuned. One key point was discussed here to understand the phenomenon: the prior sequencing of the crystal nucleation and cellular nucleation. As the supporting experiments, the gravimetric desorption data of CO2 were kinetically and thermodynamically evaluated by three diffusion equations. The concepts of local crystal nucleation and local cellular nucleation were introduced first, and the mechanism of multi‐layer arrangement was proved. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
999.
Dengsong Zhang Fuhuan NiuTingting Yan Liyi Shi Xianjun DuJianhui Fang 《Applied Surface Science》2011,257(23):10161-10167
The ceria nanospindles have been successfully synthesized via a simple template-free solvothermal treatment by employing a mixture of glycerin and water as the reaction solvent. The properties of the ceria nanospindles were characterized. A series of control experiments confirms that the reaction solvents, reaction temperature and time are the crucial factors determining the formation of ceria nanospindles, and by adjusting the experimental parameters the other ceria micro/nanostructures such as columns, spheres, and rods were obtained. The platinum coated ceria nanospindles show the excellent low-temperature catalytic activity in the oxidation of carbon monoxide as compared with other micro/nanostructures, which is mainly due to their special shape and uniformly-distributed active sites. 相似文献
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Templated Synthesis of Nitrogen‐Enriched Nanoporous Carbon Materials from Porogenic Organic Precursors Prepared by ATRP 下载免费PDF全文
Prof. Dr. Dingcai Wu Zhenghui Li Dr. Mingjiang Zhong Prof. Dr. Tomasz Kowalewski Prof. Dr. Krzysztof Matyjaszewski 《Angewandte Chemie (International ed. in English)》2014,53(15):3957-3960
A facile templated synthesis of functional nanocarbon materials with well‐defined spherical mesopores is developed using all‐organic porogenic precursors comprised of hairy nanoparticles with nitrogen‐rich polyacrylonitrile shells grafted from sacrificial cross‐linked poly(methyl methacrylate) cores (xPMMA‐g‐PAN). Such shape‐persistent all‐organic nanostructured precursors, prepared using atom transfer radical polymerization (ATRP), assure robust formation of template nanostructures with continuous PAN precursor matrix over wide range of compositions, and allow for removal of the sacrificial template through simple thermal decomposition. Carbon materials prepared using this method combine nitrogen enrichment with hierarchical nanostructure comprised of microporous carbon matrix interspersed with mesopores originating from sacrificial xPMMA cores, and thus perform well as CO2 adsorbents and as supercapacitor electrodes. 相似文献