Experimental Determination of a Third Derivative of G. (III): Differential Pressure Perturbation Calorimetry (II)
Experimental Determination of a Third Derivative of G. (III): Differential Pressure Perturbation Calorimetry (II)
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G的三阶导数的实验测定（三）：差压微扰量热法（二）
DOI：
10.1007/s10953-011-9715-1
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Y. Koga
中科院分区：
文献类型：
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作者：
Koh Yoshida;S. Baluja;A. Inaba;K. Tozaki;Y. Koga
为了直接测定二元水溶液中溶质B的偏摩尔熵-体积交叉涨落密度G的三阶导数，我们曾建立了一个差压微扰量热计。我们的尝试基本上是成功的，如别处所述（J. Solution Chem.39：431-440，2010）。但SV δ B的测定结果的不确定度为百分之几。我们直接实验测定的目的之一是以图形方式获得具有一定置信度的四阶导数量。为此，三阶导数的数据是必要的，不确定性小于百分之一。我们在第一代设备上遇到的各种困难得到了解决，并建造了一个新的设备。发现2-丁氧基乙醇水溶液的新实验结果至少好几倍。因此，我们能够第一次计算四阶导数量。在比较研究中，当这些数据可用于其他溶质（包括单醇和多元醇）的水溶液时，四阶导数的物理意义可能会变得更清楚。为此，正在开展一个项目。
Earlier we constructed a differential pressure perturbation calorimeter, in order to determine directly a third derivative of the Gibbs energyG, the partial molar entropy-volume cross fluctuation density of solute B,, in a binary aqueous solution of B. Our attempt was basically successful, as described elsewhere (J. Solution Chem. 39:431–440, 2010). However, the uncertainty of the results forSVδBwas several percent. One of the purposes of our direct experimental determination was to obtain a fourth derivative quantity graphically with some confidence. For this purpose, data of the third derivative quantity are necessary with uncertainties of less than one per cent. Various difficulties that we had on the first generation apparatus were attended to, and a new apparatus was constructed. The new experimental results for aqueous 2-butoxyethanol are found to be at least several-fold better. Hence, we were able to evaluate the fourth derivative quantity for the first time. The physical meaning of the fourth derivatives may become clearer in comparative studies when such data become available for aqueous solutions of other solutes including mono-ols and poly-ols. A project is underway to that effect.