Effects of water on the primary and secondary relaxation of xylitol and sorbitol: implication on the origin of the Johari-Goldstein relaxation.
Effects of water on the primary and secondary relaxation of xylitol and sorbitol: implication on the origin of the Johari-Goldstein relaxation.
复制标题
水对木糖醇和山梨醇的初级和次级弛豫的影响：对乔哈里-戈德斯坦弛豫起源的影响。
DOI：
10.1103/physreve.70.011503
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
K. Ngai
中科院分区：
文献类型：
--
作者：
T. Psurek;S. Maślanka;M. Paluch;R. Nozaki;K. Ngai
利用介电谱研究了水对木糖醇初级α弛豫和次级β弛豫的影响。在173 ~ 293 K的温度范围内，对无水木糖醇和木糖醇与水的混合物进行了三种不同水浓度的测量。α-松弛随着木糖醇中水浓度的增加而加速，而β-松弛的速率基本上不变。观察到无水木糖醇和混合物的α-弛豫行为的一些系统差异。我们的发现证实了Nozaki等人[J. Non-Cryst. Solids 307，349（2002）]在山梨醇/水混合物中的所有观察结果。木糖醇和山梨醇的α-和β-弛豫动力学的水的影响解释通过使用耦合模型。
Dielectric spectroscopy was employed to study the effects of water on the primary alpha -relaxation and the secondary beta -relaxation of xylitol. The measurements were made on anhydrous xylitol and mixtures of xylitol with water with three different water concentrations over a temperature range from 173 K to 293 K. The alpha -relaxation speeds up with increasing concentration of water in xylitol, whereas the rate of the beta -relaxation is essentially unchanged. Some systematic differences in the behavior of alpha -relaxation for anhydrous xylitol and the mixtures were observed. Our findings confirm all the observations of Nozaki et al. [J. Non-Cryst. Solids 307, 349 (2002)]] in sorbitol/water mixtures. Effects of water on both the alpha - and beta -relaxation dynamics in xylitol and sorbitol are explained by using the coupling model.