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
方磊
,
刘宏亮
,
刘承军
,
姜茂发
稀土
doi:10.3969/j.issn.1004-0277.2008.01.022
以重轨钢为研究对象,建立可以定量描述稀土在重轨钢中行为特性的热力学模型,并通过实验验证了模型的精确度.利用该热力学模型,研究分析了在不同氧、硫的质量分数条件下,铈加入量对重轨钢液及其凝固过程中铈的赋存状态以及夹杂物组成的影响作用规律,得到以下结论:当钢中氧、硫的质量分数较低时,随着铈加入量的增加,Ce2O2S的析出量略有减少;当钢中氧、硫的质量分数较高时,随着铈加入量的增加,Ce2O2S的析出量有所增加;铈加入量的增加以及温度的下降均有利于Ces的析出;当钢中氧、硫的质量分数较低时,在凝固过程中钢中析出CeN和固溶铈;随着铈加入量的增加,CeN的析出温度和析出量均有所增加,当CeN的析出达到平衡时,固溶铈大量析出.
关键词:
铈
,
重轨钢
,
夹杂物
,
固溶铈
,
热力学模型
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
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
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
余金秋
,
彭鹏
,
刁成鹏
,
吴浩
,
何华强
人工晶体学报
LaBr3 ∶Ce、LuI3 ∶Ce、SrI2 ∶Eu等新型卤化物闪烁晶体因其高光输出、高能量分辨率等优异的闪烁特性而引起人们的广泛关注.高纯无水稀土卤化物是生长上述闪烁晶体所必需的原料,但其制备困难和高昂成本,严重制约了这些晶体的发展和应用.本文报道了无水LaBr3、CeBr3、LaCl3、CeCl3、LuI3、GdI3、YI3、CeI3、EuI2等常用稀土卤化物的制备方法,并对其有效表征手段进行了介绍.
关键词:
闪烁晶体
,
稀土卤化物
,
制备
,
表征
章晓波
,
刘宁
,
袁红梅
,
荣春兰
硬质合金
doi:10.3969/j.issn.1003-7292.2008.01.002
为探究Mo、WC、ZrC对TiC-Ni系金属陶瓷组织的影响,真空烧结制备了TiC-Ni系金属陶瓷.利用X射线衍射仪(X-ray diffraction,XRD)、扫描电子显微镜(scanning electron microscope,SEM)、能谱仪(energy dispersive spectrometer,EDS)等研究了Mo、WC和ZrC对金属陶瓷显微组织的影响.结果表明,TiC基金属陶瓷的显微组织随着Mo、WC、ZrC的加入而逐渐细化.形成(Ti,Mo)C、(Ti,Zr,Mo)C、(Ti,Mo,W)C、(Ti,Zr,Mo,W)C、(Zr,Yi,Mo)C和(Zr,Ti,Mo,W)C等固溶体,并且在10%TiC-ZrC-14%Mo-15%WC-20%Ni-1%C试样中出现了无芯晶粒(corelesss grains)、微裂纹及微孔洞.断裂韧性测试结果表明.该显微结构能大大提高材料的断裂韧性.
关键词:
金属陶瓷
,
显微组织
,
微裂纹
,
断裂韧性
Synthetic Metals
Fused thiophene-split oligothiophenes were synthesized by Suzuki coupling. The relationship between the structure of these fused thiophene-split oligothiophenes and DH-6T (alpha.omega-dihexylsexithiophene) and their performance in OTFTs was discussed. The realignment of HTTfTTTH (2,5-bis-(5'-hexyl-[2,2']bithiophenyl-5-yi)-thieno[3,2-b] thiophene) molecule on the substrate after annealing was revealed by X-ray diffraction and atomic force microscopy. A similar but novel compound, TTfTTT (2,5-bis[2,2']bithiophenyl-5-yl-thieno[3.2-blthiophene), was also prepared and evaluated as an organic transistor material. Air stabilities of these three compounds in OTFT devices were affected mainly by chemical properties, but also by the ionization potentials (I(p)) of these materials. Among the three compounds, HTTfTTTH had a higher I(p) because the thiophene sequence was split by fused thiophene and the best air stability, due to the end-capping of its active a-positions by hexyl substitution. (C) 2009 Elsevier B.V. All rights reserved.
关键词:
OTFT;Fused thiophene;Oligothiophene;Ionization potential;Air;stability;thin-film transistors;field-effect transistors;high-mobility;organic;semiconductors;carrier mobility;copolymers;oligomers;performance;polymers
