排序方式: 共有146条查询结果,搜索用时 250 毫秒
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稀散金属化合物水溶液热力学研究 1: HCL+GaCl3+H2O体系 总被引:2,自引:1,他引:1
在HCl+GaCl3+H2O体系中,恒定五个总离子强度I=0.4,0.6,0.8,1.0,1.5mol/kg,控制混合电解质中氯化镓离子强度分数YB=0.0,0.1,0.3,0.5,0.7,并在278.15~318.15K范围内测定了五个温度的无液接电池:Pt|H2(101.325kPa)|HCl(mA),GaCl3(mB),H2O|AgCl|Ag的电动势。根据150个实验点的电动势数据,确定了HCl的活系数及其随氯化镓浓度变化规律,结果发现HCl活度系数遵守Harned规则。同时本文在Pitzer电解质溶液理论基础上提出一个确定氯化镓的pitzer参数和活度系数的方法,指出了氯化镓在这个混合电解质溶液中遵守扩展的Harned规则。 相似文献
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在MP2/6-311++G(3d,3p)水平,对PH~3...H~2O体系可能存在的氢键复合物进行了全自由度能量梯度优化,发现PH~3...H~2O体系存在三个能量极小结构A,B和C。其中结构A和B以H~2O作为质子授体,结构C以PH~3作为质子授体,结构A较结构B和C分别稳定6.52kJ/mol和8.18kJ/mol。结构A具有C~s对称性,其结构中P原子和O原子间距离为354.78nm,键角OHP为171.35ⅲ,属于接近于直线的传统型氢键结构。进一步在高级电子相关校正的MP4SDTQ下,用6-311++G(3df,3pd)基加上键函数{3s3p2d1f},通过BSSE校正,精确计算了结构A的结合能为-10.84kJ/mol。 相似文献
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本工作用配位平衡和快交换方法定量描述了二氧六环水体系中^1H和^1^7O化学位移随浓度的变化. 讨论了未配位水的结构破坏程度及其存在形式. 相似文献
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《Composite Interfaces》2013,20(3-4):291-306
Intermolecular interactions determine the reinforcement of polydimethylsiloxane (PDMS) elastomers by fumed silica, and a water interlayer on the fumed silica/PDMS interface may act as a lubricant, decreasing the interaction energy and promoting the PDMS molecule motion over the filler surface. A quantum-chemical (QCh) modelling has been performed to study a microscopic aspect of water impact on the intermolecular interactions in the system. The results obtained for a series of superclusters simulating fragments of the real silica filler surface, both hydroxylated and silylated, interacting with five-member PDMS oligomer in presence of individual water molecules and of a 'water drop', of several H-bonded water molecules, are in good agreement with results from IGC adsorption experiments. 相似文献
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Hosseln Elsazadeh 《高分子科学》2007,(4):393-397
One of the suitable methods for removing heavy metals from water is by using surface adsorption process. In this paper, the preparation of polypyrrole and its composites as adsorbents are discussed and the capability of separating mercury from water is investigated. The results indicated that the polypyrrole and its composites are able to remove mercury from aqueous media. Furthermore the adsorption percentage is related to the surface morphology, type of additives and its concentration. 相似文献
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用H^+和NO3^-离子选择电极组成的电池用电势法测定了HNO3-UO2(NO3)2-H2O系统在25°C时的HNO3的平均活度系数, 求得了同时含有^E0和 ^S0-I关系式的Pitzer方程中的两粒子和三粒子作用参数(^s0(0), ^s(1),Ψ)。用Pitzer方程计算了该系统中水的活度, 并用Pitzer方程、Mckay-Perring方法和Harned方程分别计算了系统中HNO3和UO2(NO3)2的平均活度系数。 相似文献
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