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101.
Because of the increasing complexity and cost of experiments carried out, the data for the multi-component alloy systems have frequently been obtained by numerical modelling. It is clear that the related calculations require reliable data dealing with the pure components and binary alloy systems. Selecting the reliable data concerning the pure components from the literature, the viscosities for the SAC and (SAC)1?x Cox solder alloys have been calculated using different viscosity models (geometric and physical). The viscosity decreases as the amount of tin content increases in the SAC387 alloy while the addition of the cobalt to SAC387 solder results in the increasing of the viscosity. Moreover, by computing the root mean square values between theoretical and experimental viscosities, it can be concluded that the lowest value among all models is that of obtained by Kaptay equation. 相似文献
102.
103.
Oxidation of Alloys for the Synthesis of the HT-Superconductor Tl2Ba2CaCu2O8 . For the HT-superconductor Tl2Ba2CaCu2O8 (Tl-2212) two different ways of oxidation of quenched al- oys in partly or completely closed systems which lead to reproducable oxide compounds will be described. 相似文献
104.
105.
Lyudmila A. Belyakova Anatoly M. Varvarin Nadiya V. Roik 《Applied Surface Science》2006,253(2):784-791
Direct assembly of quaternary ammonium groups onto a silica surface has been realized by use of many-stage chemical reactions. Adsorption of cholic acid in dependence on duration, equilibrium concentration, and pH solution onto a surface of silicas modified with quaternary ammonium groups has been studied. The main parameters of cholic acid adsorption have been calculated. 相似文献
106.
107.
5,11,17,23-四叔丁基-25,26,27,28-四[3-(甲氧基羰基)苄氧基]杯[4]芳烃包合性能的研究 总被引:2,自引:0,他引:2
杯芳烃是继冠醚和环糊精后的第三代主体化合物 .这类主体分子不仅可以识别和络合阳离子 ,而且还具有包合中性有机分子的性能 [1~ 5] .杯 [4]芳烃类包合物的晶体结构测定表明 ,它们可分为分子内和分子间包合两种类型 [3 ,5] ,前者是客体分子被包合在主体分子的空穴内 ,后者是客体分子被包合在主体分子之间 .对叔丁基杯 [4]芳烃的下沿酚氧基与上沿均可进行化学修饰得到不同的杯 [4]芳烃衍生物 .最早报道的对叔丁基杯 [4]芳烃及其衍生物的分子内包合物是与甲苯或乙腈的 1∶ 1包合物 [4 ,5] ,客体分子依靠 CH3 -π的作用被包结在主体分子内[6]… 相似文献
108.
Yuandong Wu 《Journal of solid state chemistry》2007,180(1):113-118
The quaternary compound Rb2BaNb2Se11 has been synthesized by reacting Nb metal with an in situ formed flux of Rb2Se3, BaSe and Se at 773 K. Rb2BaNb2Se11 crystallizes in the monoclinic space group P21/c with four formula units and lattice parameters a=7.8438(5) Å, b=13.6959(6) Å, c=17.0677(13) Å, β=97.917(9)°. The structure consists of one-dimensional anionic chains formed by interconnection of dimeric [Nb2Se11] units. The chains are directed along the crystallographic c-axis with Rb+ and Ba2+ ions being located between the chains. The [Nb2Se11] units are formed by face sharing of two NbSe7 bipyramids and are joined by Se22− dianions to form infinite 1∞[Nb2Se114−] chains. The compound was characterized with infrared spectroscopy in the FIR region, Raman and UV/Vis diffuse reflectance spectroscopy. 相似文献
109.
Tubes of paint from the Arnold Schönberg Center, Vienna, have been investigated using gas chromatography – mass spectrometry. In total, 23 oil paint samples from paint tubes in different stages of dryness have been examined. The analyses have suggested that the principal painting medium in Schönberg’s palette is linseed oil, mixed with resinous compounds, essential oils, and beeswax, which have been simultaneously identified using off-line transmethylation with TMTFAH as a methylation reagent. 相似文献
110.