材料期刊网

Mn2+掺杂对V2O5纳米材料结构与电化学性能的影响

李兆龙 , 孙华君 , 徐杰 , 张晓艳 , 黄胜男 , 朱泉峣 , 陈文 , Galina S.Zakharova

无机材料学报 doi:10.3724/SP.J.1077.2013.13137

以V2O5粉末、H2O2和Mn(CH3COO)2·4H2O为原料,采用水热法制备了纳米结构的锂离子电池阴极材料MnxV2O5.运用X射线衍射(XRD)、X射线光电子能谱分析(XPS)和扫描电镜(SEM)测试对制备的材料进行结构和形貌表征,并利用充放电测试和交流阻抗测试研究了样品的电化学性能.结果表明:随着锰掺杂量的增加,V2O5的正交晶型层状结构未发生改变,其层间距逐渐扩大,形貌由纳米短棒状向纳米带簇状变化.电化学测试表明:Mn2+掺杂提高了V2O5的电化学性能,其首次充放电效率由70.8％提高到90％以上;Mn0.01V2O5经过90次充放电循环后,其容量仍为192.2 mAh/g.Mn2+掺杂对V2O5电极材料的离子电导率有影响,Mn0.02V2O5离子电导率由未掺杂时的6.27× 10-4 S/cm提高到1.58×10-3 S/cm.

关键词: MnxV2O5 , 电极材料 , 离子掺杂 , 电化学性能

Thermodynamic Behaviour of Fe-S-RE,Fe-Csat.-S-RE,Ni-S-RE,Cu-S-RE Solutions

Ting DU Longmei WANG Yeming WU Yuqing ZHANG Aisheng LIU Central Iron and Steel Research Institute , Beijing , 100081 , China

材料科学技术（英文）

The temperature dependences of the equilibrium constants for the reactions RES_((S))=[RE]+[S]. (RE=Ce,La,Nd,Sm,Y),of the standard Gibbs energies for the RES formed and of the interaction coefficients between RE elements and S for the Fe-base,Ni-base and Cu-base solutions are sum- marized.

关键词: thermodynamics , null , null , null , null

Quantum transport of Au-S-S-Au nanoscale junctions

Applied Physics Letters

Transport in S(2) molecules sandwiched between Au electrodes is investigated with a combination of density functional theory and the non-equilibrium Green's function method. We consider four different configurations and find that their conductances are related to the details of the bonding geometry. When S(2) connects to pyramidal-shaped electrodes at the top site, the transmission is governed by a resonance and is strongly affected by the bias. In contrast, the transport of the remaining three configurations is through several closely spaced broad molecular orbitals, and the transmission coefficient is almost flat around the Fermi level. (C) 2012 American Institute of Physics. [doi:10.1063/1.3665614]

关键词: conductance;molecule

EQUILIBRIUM OF Mg-S IN Ni MELTS

WANG Conghua HAN Qiyong University of Science and Technology Beijing , Beijing , China WANG Conghua Faculty of Physical Chemistry of Metallurgy , University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

The equilibrium of Mg-S in Ni melt was studied by the method of vapour equilibrium in a sealed chamber.At 1530℃ the equilibrium constant of the reaction MgS_(s)=Mg_(Ni)+S_(Ni)and the activity interaction coefficient were determined as K_(MgS)=6.76×10~(-5)and e_S~(Mg)=-9.1.

关键词: Equilibrium constant , null , null , null , null

S49钢轨轧制工艺设计

陈亚平 , 王彦中 , 陶功明

钢铁钒钛 doi:10.3969/j.issn.1004-7638.2002.01.007

结合攀钢轨梁厂工厂特点及S49钢轨断面特点,论述了S49钢轨的轧制工艺设计,并着重阐述了孔型系统的选择和孔型参数的确定,同时设计了导卫装置等.通过孔型系统的优化设计,使S49钢轨一次试轧成功.

关键词: S49钢轨 , 孔型设计 , 导卫装置

EQUILIBRIA OF Sr,Ba AND O,S IN LIQUID Fe

YUE Kexiang DONG Yuanchi East China Institute of Metallurgy , Ma'anshan , China

金属学报(英文版)

The equilibrium constants between Sr-O,Ba-O and Sr-S,Ba-S in liquid iron at 1570℃ and the interaction coefficients concerning these elements have been determined as follows: K_(Sro)=1.897×10~(-7),e_O~(Sr)=-43.8 K_(BaO)=8.204×10~(-8),e_O~(Ba)=-98.0 K_(SrS)=8.356×10~(-7),e_S~(Sr)=-3.9 K_(BaS)=4.083×10~(-7),e_S~(Ba)=-3.5

关键词: equilibrium , null , null , null , null

H2S应力腐蚀试验用H2S气通设计

孙耀峰

腐蚀学报（英文） doi:10.3969/j.issn.1002-6495.2001.z1.007

在满足H2S应力腐蚀试验的试验条件下,设计了H2S应力腐蚀实验室中H2S气体的通气装置.设计方案切实易行,安全可靠;实现了出口H2S气体的吸收再利用,减少了对环境的污染.

关键词: H2S气体 , 设计方案 , H2S应力腐蚀试验 , 环境保护

Thermodynamic discussion on Young's equation in wetting

Zeitschrift Fur Metallkunde

Young's equation is discussed on a thermodynamic basis. The result shows that the equation is a thermodynamic equilibrium of the wetting system rather than a force balance. The equilibrium satisfies the general equilibrium condition, that is, Gibbs free energy should be minimum when the wetting equilibrium is reached. The validity of Young's equation is only limited to some special cases, namely if the droplet shape is an exact sphere sector. It implies that Young's equation can only be used in the case without the action of gravity. If the curve of the liquid surface changes, the term of cos theta in Young's equation should be replaced by another functional form of the contact angle theta. In the discussion, the author suggests that, in the case of a solid, the surface energy should be considered rather than the surface tension, and the concept of a solid surface tension should be reconsidered based on the difference between a liquid surface and a solid surface.

关键词:

NUMERICAL SIMULATION OF CASTING'S MOLD FILLING PROCESS

J.X. Zhou , R.X. Liu , L.L. Chen , D.M. Liao , H.S. Wei

金属学报(英文版)

Numerical simulation of casting's mold filling process is the main and the most important aspect of the foundry CAE technology. But it is time-consuming; it may take dozens of hours or several days. While with the development of computer hardware, numerical simulation of casting's mold filling process has made rapid progress. The simulation results, therefore, have become more and more practical. This study tries to find some clues of the computational time of mold filling process. Firstly, this paper introduces mathematic model and the basic route of numerical simulation of casting's mold filling process. Then the computational time of mold filling process has been carefully studied, and some new and useful results have been gained from the study of the computational time. Finally, this paper has given some real applications of numerical simulation of casting's mold filling process.

关键词: numerical simulation , null , null

Ni3S2-FeS-Cu2S冰镍体系的表面张力

严丽君 , 王伟 , 曹战民 , 乔芝郁

稀有金属 doi:10.3969/j.issn.0258-7076.2000.03.001

运用几何模型 (Kohler及Toop模型) 和通用溶液模型 (Chou模型), 由Ni3S2-FeS、 FeS-Cu2S和Cu2S-Ni3S2三个二元边界体系的表面张力计算了Ni3S2-FeS-Cu2S三元系表面张力. 计算结果与实验值 (实验误差为±2.5%) 十分吻合, 1473 K下Ni3S2-FeS-Cu2S冰镍体系的等表面张力曲线有较高的可信度, 对分析研究镍的闪速熔炼和转炉吹炼过程有重要意义.

关键词: 冰镍 , 表面张力 , 几何模型 , 通用溶液模型