首页> 外文期刊>Journal of the Serbian Chemical Society >Volumetric, viscometric and refractive index behaviour of amino acids in aqueous glycerol at different temperatures
【24h】

Volumetric, viscometric and refractive index behaviour of amino acids in aqueous glycerol at different temperatures

机译:不同温度下甘油水溶液中氨基酸的体积,粘度和折射率行为

获取原文
获取原文并翻译 | 示例
获取外文期刊封面目录资料

摘要

Densities, ρ, viscosities, η, and refractive indices, n_D, of solutions of some amino acids (glycine, DL-alanine, DL-α-amino-n-butyric acid, L-valine and L-leucine) in the concentration range 0.02 to 0.10 m in 5% (v/v) aqueous glycerol were determined at 298.15, 303.15, 308.15 and 313.15 K. These experimental data were used to calculate the apparent molar volumes, φ_v, the infinite dilution apparent molar volumes, φ_v~0, the partial molar volumes of transfer, φ_v~0_((tr)), of the amino acids from aqueous to aqueous glycerol solution, as well as the viscosity A and B coefficients of the Jones-Dole equation of the amino acids. The free energies of activation of viscous flow, Δμ_1~(0#) and Δμ_2~(0#) per mole of solvent and solute, respectively, were obtained by application of the transition-state theory to the B coefficient data and the corresponding activation enthalpy, ΔH~*, and entropy, ΔS~*, were also determined. The φ_v~0, B coefficients and Δμ_2~(0#) were found to vary linearly with increasing number of carbon atoms in the alkyl chain of the amino acids, and they were split into contributions from the zwitterionic end groups (NH_3~+, COO~-) and methylene (CH_2) groups of the amino acids. The experimental values of the refractive indices, n_D, were used to calculate the molar refractive indices, R_D, of the amino acids + aqueous glycerol ternary mixtures. The results were interpreted in the light of the solute-solvent and solute-solute interactions in the mixed solvents.
机译:浓度范围内某些氨基酸(甘氨酸,DL-丙氨酸,DL-α-氨基-正丁酸,L-缬氨酸和L-亮氨酸)溶液的密度ρ,粘度η和折射率n_D在298.15、303.15、308.15和313.15 K下测定了5%(v / v)甘油水溶液中的0.02至0.10 m。这些实验数据用于计算表观摩尔体积φ_v,无限稀释表观摩尔体积φ_v〜0 ,从甘油水溶液到水溶液的氨基酸转移的部分摩尔体积φ_v〜0 _((tr))以及氨基酸的Jones-Dole方程的粘度A和B系数。通过将过渡态理论应用于B系数数据和相应的活化,获得了每摩尔溶剂和溶质的粘性流活化的自由能,分别为Δμ_1〜(0#)和Δμ_2〜(0#)。还确定了焓ΔH〜*和熵ΔS〜*。发现φ_v〜0,B系数和Δμ_2〜(0#)随着氨基酸烷基链中碳原子数的增加而线性变化,并被分为两性离子端基(NH_3〜+,氨基酸的COO-)和亚甲基(CH_2)。折射率的实验值n_D用于计算氨基酸+水性甘油三元混合物的摩尔折射率R_D。根据混合溶剂中的溶质-溶剂和溶质-溶质相互作用来解释结果。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号