Dielectric spectra of mono- and disaccharide aqueous solutions
Dielectric spectra of mono- and disaccharide aqueous solutions
复制标题
单糖和二糖水溶液的介电谱
DOI：
10.1063/1.1463426
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发表时间：
2002
影响因子：
4.4
通讯作者：
U. Kaatze
中科院分区：
文献类型：
--
作者：
K. Fuchs;U. Kaatze
测定了单糖D-木糖、D-半乳糖、D-葡萄糖、D-果糖、甲基-β-D-木糖和甲基-β-D-葡萄糖以及双糖D-乳糖、D-麦芽糖和D-蔗糖水溶液的复介电常数谱。为了避免任何系统误差，使用了各种实验装置，每个装置都与特定的测量范围相匹配，以覆盖从300 kHz到40 GHz的频域。在一些特征细节上，我们对麦芽糖溶液的光谱与Weingartner等人最近报道的光谱有所不同。作者声明：[J.Chem.太棒了。115、1463(2001)]。在c=1 m ol/L处的单糖谱和c⩽0.5 m ol/L处的双糖谱显示了碳水化合物和水偶极矩相当均匀的松弛，这可以用Cole-Cole松弛时间分布很好地描述.在较高溶质浓度下，介电谱可用两个弛豫项较好地表示，尽管用Cole-Cole规范对实验数据进行了插补。
Complex (dielectric) permittivity spectra of aqueous solutions of the monosaccharides D-Xylose, D-Galactose, D-Glucose, D-Fructose, Methyl-β-D-xylose, and Methyl-β-D-glucose, as well as the disaccharides D-Lactose, D-Maltose, and D-Sucrose have been measured. In order to avoid any systematic errors, various experimental setups, each matched to a particular measuring range, have been used to cover the frequency domain from 300 kHz to 40 GHz. In some characteristic details our spectra for maltose solutions deviate from those recently reported by Weingartner et al. [J. Chem. Phys. 115, 1463 (2001)]. The monosaccharide spectra at c=1 mol/l and the disaccharide spectra at c⩽0.5 mol/l reveal a rather homogeneous relaxation of the carbohydrate and water dipole moments, which can be well represented by a Cole–Cole relaxation time distribution. At higher solute concentration the dielectric spectra are favorably represented by two relaxation terms, though interpolation of the experimental data by the Cole–Cole spec...