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Te-Se glass and adding As,Ge elements to itare studied with Selt-Consistent-Field Discrete Variatioal X_α(SEF-DV-X_α),one of the molecule orbital calculating meth-ods in quantum chemistry.The chemical bonding is used todiscuss the relations between structures and properties with thevarations of compositions of the glasses.The calculated re-sults show that the strength of covalent and ionic bonds areboth in the order of Ge-Se>As>Se>Te-Se,which is consis-tent with the experimental result of the glass-transition tem-perature(T_g) of the corresponding glasses.The Te-I bond inwhich Ⅰ atom is one-coordinate is sstronger than that in whichⅠ atom is two-coordinate,As-Ⅰ and As-As bonds are bothstronger than the two types of Te-Ⅰ bonds.The waek Te-Ⅰbonds have been replaced by the stronger As-Ⅰ and As-Asbonds,which is just the reason why As addition in TeX glass-es can obviously improve the thermal and chemical properties. 相似文献
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针对高风压多雨地区建筑外保温条件下外墙渗漏较多的现状,结合台州市信达都市绿苑工程实例,对渗漏的原因进行分析,提出了加抗裂剂和防裂网解决渗漏的方法. 相似文献
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结合钻孔灌注桩在工程中的广泛应用,介绍了软土地区嵌岩钻孔灌注桩成孔方法和设备的选择,探讨了钻孔灌注桩工艺流程及施工要点,提出了质量通病的控制对策,积累了钻孔灌注桩的施工经验。 相似文献
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