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71.
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73.
Anthony Fucaloro Robert Pinnell Andrew Zanella Karen Conrad Yan Pu 《Journal of solution chemistry》2006,35(9):1245-1254
Both the partial molar volumes (V°
2m
refractions (R°
2m
) of the solutes at infinite dilution have been determined at 20 °C for a series of six octahedral N6-coordinated cobalt(III) species featuring five coordinated ammonia ligands along with a sixth N-coordinated organonitrile of increasing ligand size (from acetonitrile to sebaconitrile). The experimental values for V°
2m
are consistent with the relative sizes of the ligands but show larger values than those generated by computer modeling as the size of the cation increases, presumably due to the void space of the cation which increases with the size of the nitrile ligand. 相似文献
74.
本文报道了新显色剂偶氮氯膦-间磺酸基苯在表面活性剂(CPB)存在下与稀土元素的显色反应具有较高的灵敏度和选择性。通过实验研究了多元络合物的吸收光谱、络合物的组成以及反应的最佳条件。用本方法测定了实际样品中的稀土总量,获得了满意的结果。 相似文献
75.
Densities and molar heat capacities have been measured for mixtures ofN,N-dimethylformamide with dimethylsulfoxide, acetonitrile, andN-methylformamide at 25°C over the complete mole fraction range. From these data the apparent molar volumes and heat capacities have been calculated for both components. These quantities, as a function of the mole fraction, deviate very little from their molar values, indicating that the mixtures can be regarded as almost ideal. 相似文献
76.
《Physics and Chemistry of Liquids》2012,50(6):615-623
Densities and viscosities have been measured for twelve 1-alkanols from methanol to 1-dodecanol at temperatures ranging from 303.15 to 323.15?K. Molar volumes, V m , have been calculated from the density data, which have been found to follow the additive equation, V m ?=?V CH3 ?+?nV CH2 ?+?V OH, where n is the number of CH2 groups. V m have been plotted against n, showing an excellent linear relationship. The average values of V CH2 at 303.15?K and 323.15?K have been determined from the slopes of this equation. The viscosities have been found to increase almost exponentially with the number of carbon atoms at different temperatures. The thermodynamic activation parameters, free energy, ?G ≠, enthalpy, ?H ≠, and entropy, ?S ≠ for viscous flow have been plotted against the number of C atoms – all have been found to increase with the chain length of 1-alkanols. 相似文献
77.
78.
79.
80.
Liu Hengli 《高等学校化学研究》1990,(4)
The lattice parameters a and the molar volumes Km of Pb-based a-phase solid solutions in the Pb-Sn-Cd ternary system were determined by means of X-ray diffraction. The lattice parameters a vary linearly with the molar fractions, the molar volumes show a positive deviation from the ideal solution behaviour, and the contribution of the solute Cd to the excess molar volumes V is much larger than that of the solute Sn. According to Vegard' s law orsub-regular solution model, the relationship between the experimental data of a or Vm andthe compositions of alloy is obtained by the mathematic regressive method, the prediction precisions of the both formulae are within the limits of experiment error. 相似文献