欢迎登录材料期刊网

材料期刊网

高级检索

  • 论文(42)
  • 图书()
  • 专利()
  • 新闻()

0℃时YI3-C6H12N4·HI-H2O的相图及YI3·C6H12N4·HI·14H2O的合成与表征

王丽 , 吴希文 , 张晨鼎 , 张通 , 简丽 , 武朝军 , 周涛

稀土 doi:10.3969/j.issn.1004-0277.1999.02.003

采用湿渣法研究了0℃时碘化钇(YI3)-乌洛托品氢碘酸盐(C6H12N4.HI)-水(H2O)的三元体系相平衡,绘制了该体系的等温溶解度相图,相图分析结果表明,该体系中有组成为YI3.C6H12N4.HI.14H2O的配合物生成,对所得配合物进行了化学分析、X-射线粉末衍射、红外光谱、差热-热重分析,测定了其密度、晶体轴性,确定了配合物结构中的配位关系.

关键词: 相平衡 , 碘化钇 , 乌洛托品氢碘酸盐 , 配合物

Two-step magnetization in a spin-chain system on the triangular lattice: Wang-Landau simulation

Physical Review B

The Wang-Landau algorithm is used to study the thermodynamic and magnetic properties of triangular spin-chain system based on two-dimensional Ising model in order to understand the magnetic-order dynamics in Ca(3)Co(2)O(6) compound. The calculated results demonstrate that the equilibrium state of the rigid spins produces the two-step magnetization curve at low temperature even when the random-exchange term is considered. This work indicates that the four-step magnetization behavior observed experimentally must be due to the nonequilibrium magnetization.

关键词: calcium compounds;exchange interactions (electron);Ising model;magnetisation;thermodynamics;one-dimensional ca3co2o6;density-of-states;compound ca3co2o6;phase-diagram;proteins;crystal

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

白色开金的色度参数和白色分级

宁远涛

贵金属

  评述了合金元素对Au的漂白效果和机制,介绍了白色开金的几种色度参数,如CIE-L a*b*色度参数和颜色盒,CIE-LAB-C-H-L米制色度参数和基于CIE-XYZ色度参数的ASTM D1925黄色指数YI,讨论了某些白色开金的色度参数与冶金学特征。基于金合金的漂白效应与合金成分的密切关系,ASTM D1925黄色指数YI为设计白色开金成分提供了基本的指南。

关键词: 金属材料 , Au合金 , 白色开金 , 色度参数 , 色度图

抗氧剂在聚丙烯中的应用研究

徐旸 , 汪艳 , 傅轶

合成材料老化与应用

采用多次挤出的方法和氧化诱导期(OIT)方法考察了抗氧剂对聚丙烯热氧稳定性的影响,测定了各次挤出试样的熔体流动速率(MFR)、黄度指数(YI)、力学性能以及氧化诱导期(OIT).实验结果表明:添加由主抗氧剂1010和辅抗氧剂168组成的复合抗氧剂后聚丙烯的熔体流动速率(MFR)、黄度指数(YI)、拉伸强度和冲击强度、氧化诱导期(OIT)与未添加抗氧剂的聚丙烯相比降低明显减缓,说明抗氧剂可有效抑制聚丙烯的老化,延长其使用寿命.

关键词: 聚丙烯 , 抗氧剂 , 热稳定性

改进的Vrentas-Duda扩散模型及其应用(Ⅰ)预测弱极性分子在聚合物膜中的扩散系数

赵欣 , 李继定 , 陈剑 , 陈翠仙

膜科学与技术 doi:10.3969/j.issn.1007-8924.2003.06.003

在膜分离过程中,渗透物分子在聚合物膜内的扩散过程,是影响聚合物膜分离性能的关键因素.详细考察了目前被广泛使用的Vrentas-Duda扩散模型,对其进行改进,提出了新的计算ζ的公式.根据新提出的公式,对聚苯乙烯/甲苯(PS/toluene)、聚苯乙烯/乙苯(PS/ethylbenzene)、聚乙酸乙烯酯/甲苯(PVAc/toluene)3种体系中弱极性渗透物分子的扩散系数进行了预测,其较之原Vrentas-Duda扩散模型、Ju改进的Vrentas-Duda扩散模型有更好的预测结果.

关键词: 自由体积 , 扩散模型 , 聚合物膜 , 扩散系数

Effect of interstitial hydrogen on cohesive strength of Al grain boundary with Mg segregation

材料科学技术(英文)

The effect of interstitial hydrogen on the cohesion of the Al Sigma=11(113) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang using the first-principles density function calculation. The results indicate that interstitial H behaves as an embrittler from "strengthening energy" analysis. The reduced GB cohesion due to the presence of H at the GB is attributed to the low affinity between H and Al, and the weakened bonding of Al atomic pairs perpendicular to GB plane.

关键词: hydrogen;grain boundary;Al-Mg alloys;pseudopotentials;1st-principles

Effect of Interstitial Hydrogen on Cohesive Strength of Al Grain Boundary with Mg Segregation

Xiaoguang LIU , Xiaowei WANG

材料科学技术(英文)

The effect of interstitial hydrogen on the cohesion of the Al ∑=11(113) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang using the first-principles density function calculation. The results indicate that interstitial H behaves as an embrittler from "strengthening energy" analysis. The reduced GB cohesion due to the presence of H at the GB is attributed to the low affinity between H and Al, and the weakened bonding of Al atomic pairs perpendicular to GB plane.

关键词: Hydrogen , null , null

Mean-field theory for ferroelectricity in Ca(3)CoMnO(6)

Physical Review B

An elastic Ising model for CoMnO(6) chain is proposed to explain the ferroelectricity induced by collinear magnetic order in Ca(3)CoMnO(6), and then a mean-field theory with interchain spin interactions based on this model is developed. With inclusion of the dynamics of polarization domains at finite temperature, we address the rationality of our theory by the good agreement of the calculated electric polarization and dielectric susceptibility with the reported data on Ca(3)Co(2-x)Mn(x)O(6) (x approximate to 0.96) [Y. J. Choi, H. T. Yi, S. Lee, Q. Huang, V. Kiryukhin, and S.-W. Cheong, Phys. Rev. Lett. 100, 047601 (2008)], a typical diatomic Ising spin chain system, while the predicted magnetic susceptibility shows some difference from experiment, the reason of which is discussed.

关键词: calcium compounds;cobalt compounds;dielectric polarisation;ferroelectricity;Ising model;magnetic susceptibility;multiferroics;optical susceptibility;one-dimensional oxides;magnetic-properties;multiferroics;ca3co1+xmn1-xo6

  • 首页
  • 上一页
  • 1
  • 2
  • 3
  • 4
  • 5
  • 下一页
  • 末页
  • 共5页
  • 跳转 Go

出版年份

刊物分类

相关作者

相关热词