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Beijing Wuzi University is a higher education institution based in the capital of China, Beijing. It is also refer to Beijing Wuzi University. Wikipedia.

Qiu B.,Beijing University of Technology | Zhao X.,Beijing University of Technology | Xia D.,Beijing University of Technology | Xia D.,Beijing Materials University
Journal of Alloys and Compounds | Year: 2013

This study reports a novel strategy of preparing CoS2/reduced graphene oxides (RGO) nanocomposites by employing graphene oxides (GO) as an oxidizing agent and Na2S2O3 as a reducing agent. CoS2 can be in situ synthesized with GO being reduced. X-ray diffraction (XRD), Raman spectrometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical test are used to characterize the nanocomposite. The CoS2 particles with the size of 150 nm are dispersed in the networks made from thin RGO nanosheets. The CoS 2/RGO nanocomposite as an anode material for lithium-ion batteries can deliver excellent reversible capacity retention (640 mA hg-1) after cycling 50 times when tested at 100 mA g-1 and rate performance. The enhanced electrochemical properties can be attributed to the nanoscale particles sizes of CoS2 in addition to the effects of RGO networks in preventing the agglomeration of CoS2 and absorbing lithium polysulfides during the charge-discharge processes. © 2013 Elsevier B.V. All rights reserved. Source

Samanta D.,Virginia Commonwealth University | Wu M.M.,Virginia Commonwealth University | Wu M.M.,Beijing Materials University | Jena P.,Virginia Commonwealth University
Inorganic Chemistry | Year: 2011

Electron affinity (EA) is one of the most important factors that govern reactivity of atoms and molecules. Chlorine, with the highest electron affinity (3.6 eV) of all elements in the periodic table, is a classic example of reactive elements. Over past thirty years, much research has been done to expand the scope of molecules with electron affinities even larger than that of Cl. These molecules, called superhalogens, have the general formula MXn+1 where M is a metal atom, X is a halogen atom, and n is the valency of the metal. In this paper we explore the potential of pseudohalogens such as CN, which mimic the chemistry of halogens, to serve as building blocks of new superhalogens. Using calculations based on density functional theory, we show that when a central Au atom is surrounded by CN moieties, superhalogens can be created with electron detachment energies as high as 8.4 eV. However, there is a stark contrast between the stability of these superhalogens and that of conventional AuFn superhalogens. Whereas AuFn complexes are stable up to n = 5 for neutrals and n = 6 for anions, Au(CN)n complexes (with CN moieties attached individually) are metastable beyond n = 1 for neutrals and n = 3 for anions. We investigate the nature and origin of these differences. In addition, we elucidate important distinctions between electron affinity (EA) and adiabatic detachment energy (ADE), two terms that are often used synonymously in literature. © 2011 American Chemical Society. Source

Li Y.,Peking University | Sun Q.,Beijing Materials University
Advanced Energy Materials | Year: 2016

The increasing concentration of CO2 in the atmosphere, and the resulting environmental problems, call for effective ways to convert CO2 into valuable fuels and chemicals for a sustainable carbon cycle. In such a context, CO2 electrocatalytic reduction has been hotly studied due to the merits of ambient operational conditions and easy control of the reaction process by changing the applied potential. Among the various systems studied, Cu and Au are found to possess the highest Faradaic efficiency toward cathodic electrocatalytic conversion of CO2 to hydrocarbons and CO, respectively. However, both of them suffer from large overpotentials owing to the limitations imposed by the scaling relations between the carbonaceous adsorbates. Therefore, establishing how to break the scaling relations for effective electrochemical conversion of CO2 has become an urgent research topic. The recent advances in breaking the adsorption energy scaling relations to reduce the overpotential, improve the catalytic activity and suppress the side reaction, are summarized. The origin of the scaling relations, their negative effects on CO2 electrocatalysis, and the strategies for breaking the limitations are discussed. Some suggestions for future study are also proposed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Xie J.,Beijing Natural Science Foundation Commission Office | Xia D.-G.,Beijing Materials University
Fuel Cells | Year: 2013

Pt29Ru51P15 particles with a uniform size distribution of 2 nm supported on multi-walled carbon nanotubes (CNTs) have been prepared with the assistance of thioglycolic acid functionalization using NaH2PO2 · H2O as a reducing agent. The Pt29Ru51P15/CNTs has been characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Its electrochemical properties have been examined by cyclic voltammetry (CV) and chronoamperometry (CA). The results show that Pt29Ru51P15/CNTs has a much narrower particle size distribution with no formation of aggregates, a greater electrochemically active surface area, and higher electrocatalytic activity for the electro-oxidation of methanol Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Zhu Q.,Beijing Materials University
Energy Procedia | Year: 2011

This paper apprises the law of "Plastic-bag ban (PBB)" and points out that the law is necessary, feasible and effective. The success of the PBB policy is represented by the fact that the policy is consistent with the public opinion, and has definite control target. PBB has been properly carried out in supper markets, and has reduced the usage of plastic bags by two thirds. However, the public understanding of PBB needs to be further deepened. The paper analyses the cause of illegal use and wholesaling of ultra-thin plastic bags in peddler' and wholesale markets, and advances some policy suggestions including strengthening the propaganda of PBB and the regulation over peddler's markets and production of plastic bags, increasing the price of plastic bags and establishing relevant law and regulation systems. © 2011 Published by Elsevier Ltd. Source

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