JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2015
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IF 2.037
Chunli Liu,Li Zhou,Liqun Fan,Chonggui Ren
Enthalpies of solution and densities of glycylglycine in aqueous solutions of NaNO3, NaClO4, and Na2SO4 were measured at 298.15 K. Standard transfer enthalpies (ΔtrH0), standard transfer partial molar volume (ΔtrVϕ0), and hydration numbers (Nh) have been determined for glycylglycine. All of the ΔtrH0 values are negative in the three salt solutions. The relative order of ΔtrH0 in the same concentration of 1–1 type salts is NaNO3 > NaClO4. The ΔtrH0 in low concentration of Na2SO4 solutions is between the corresponding values in NaNO3 and NaClO4 solutions. With increasing Na2SO4 concentration, the ΔtrH0 values exceed that in NaNO3 solutions. The ΔtrVϕ0 values are positive and vary in the sequence Na2SO4 > NaNO3 > NaClO4. The results were discussed in terms of various interactions.
研究领域:
生物化学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
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2023
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IF 5.7
Zhuanfang Jing,Yongquan Zhou,Toshio Yamaguchi,Koji Yoshida,Kazutaka Ikeda,Koji Ohara,Guangguo Wang
Ion hydration in aqueous solutions plays a paramount role in many fields. Despite many studies on ion hydration, the nature of ion hydration is not consistently understood at the molecular level. Combining neutron scattering (NS), wide-angle X-ray scattering (WAXS), and molecular dynamics (MD), we quantify the ionic hydration degree (hydration ability) systematically for a series of alkali metal and halide ions based on static and dynamic hydration numbers. The former is based on the orientational correlation of water molecules bound to an ion derived from the positional information from NS and WAXS. The latter is defined as the mean number of water molecules remaining in the first coordination shell of an ion over a residence time of bound water molecules around the ion from MD. The static and dynamic hydration numbers distinguish hydration from coordination and quantify the ionic hydration degree, which provides a valuable reference for understanding various phenomena in nature.
研究领域:
物理化学
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化学物理
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溶液化学
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分子模拟
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2015
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IF 2.679
Xiaofen Ren,Chunying Zhu,Youguang Ma
Densities ( ρ ) and viscosities ( η ) of glycine, l -alanine, l -valine, l -threonine and l -arginine in (0.2, 0.4, 0.6, 0.8 and 1.0) mol · kg −1 aqueous sorbitol solutions have been measured at T = (293.15, 303.15, 313.15 and 323.15) K under atmospheric pressure. The apparent molar volume ( V φ ) and the limiting partial molar volumes of amino acids ( V φ 0 ) were calculated through the density data. And the limiting partial molar volumes of transfer (Δ tr V φ 0 ) and interaction coefficients V ab , and V abb were also determined. The extended Jones–Dole equation was used to correlate the viscosities in order to obtain viscosity B -coefficient and the free energies of activation per mole of solvent (Δ μ 1 0≠ ) and solute (Δ μ 2 0≠ ). The limiting partial molar volume of transfer and the free energies of activation per mole of both solvent (Δ μ 1 0≠ ) and solute (Δ μ 2 0≠ ) were discussed on the basis of the co-sphere overlap model and transition state theory, respectively. The hydration number of amino acids was computed using the obtained limiting partial molar volume and viscosity B -coefficient. Additionally, the group contribution method was applied to determine the respective contribution of (NH 3 + , COO − ), CH 2 , OH and CNHNHNH 2 to V φ 0 and B -coefficient.
研究领域:
物理化学
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溶液化学
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热力学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2024
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IF 6.3
Yang Li,Shuijing Wang,Hengming Huang,Jiahui Kou,Chunhua Lu,Zhongzi Xu,Jinhua Ye
Faster OH − transfer for efficient adsorption on catalysis is key to accelerating the oxygen evolution reaction (OER). The diffusion of OH − in electrolyte mainly involves two mechanism which is dependent on the water coordination number (CN): Grotthuss diffusion (4 CN) and vehicular diffusion (5 CN). The Grotthuss diffusion is much faster but the vehicular diffusion of OH − is predominant in the electrolyte. Herein, negatively charged kaolin, which are simply dispersed in the electrolyte, are utilized to provide surface electrostatic attraction to H 2 O and repulsion to OH − to reduce the OH − CN from 5 to 4 for rapid Grotthuss diffusion. This contributes to the accelerated OH − adsorption which facilitates the charge transfer, the formation and the deprotonation of *OOH leading to enhanced OER performance. The OH − CN recovery from 4 to 5 is proved quite slow after leaving the kaolin surface, breaking the limitation that kaolin must be on the catalyst surface. This strategy exhibits universality for various electrocatalysts with reduced overpotential by 10–246 mV at 10 mA cm −2 . We provide a clean, simple and low-cost way to promote the industrial development of alkaline water electrolysis.
研究领域:
电化学
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材料科学
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催化
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能量转换
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2017
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IF 3.648
Jing Zhang,Taotao Fu,Chunying Zhu,Youguang Ma
Densities and viscosities of glycine, L-alanine, L-valine, L-threonine and L-arginine in aqueous (0.1–0.5) mol·kg − 1 myo -inositol solutions were measured at T = (293.15, 303.15, 313.15 and 323.15) K and p = 0.101 MPa. The volumetric properties such as the apparent molar volume ( V φ ), the limiting partial molar volume ( V φ 0 ), the limiting partial molar volumes of transfer (Δ tr V φ 0 ), the limiting apparent molar expansibility ( E 2 0 ), Hepler's constant and the isobaric thermal expansion coefficient ( α 2 ) were calculated through density. The viscometric properties such as the B -coefficient, the free energies of activation per mole of solvent (Δ μ 1 0 ≠ ) and solute (Δ μ 2 0 ≠ ) were obtained from the experimental viscosity data. The derived parameters hydration number and solvation number were also calculated through apparent molar volume and B -coefficient. From the volumetric and viscometric properties, the solute-solute and solute-solvent interactions in the studied systems were analyzed on the basis of co-sphere overlap model and transition state theory . Finally, the group contribution method was applied to calculate the contribution of (NH 3 + , COO − ), CH 2 , OH and CNHNHNH 2 of amino acids to V φ 0 , B -coefficient and Δ μ 2 0 ≠ .
研究领域:
物理化学
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热力学
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溶液化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
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IF 6.165
Zhenning Yan,Xingxing Cao,Meng Sun,Lulu Zhang
The pharmaceutically active form of an ionic liquid , cetylpyridinium salicylate ([CetPy][Sal]), was synthesized, and the intermolecular interactions of [CetPy][Sal] with amino acids (glycine, L-alanine, L-valine, and L-leucine) and glycylglycine (AAGG) in aqueous media were investigated by measuring the density, conductivity and UV–visible spectra at different temperatures. The measured density data was used to compute the apparent molar volume at infinite dilution, V 2, φ 0 , the hydration number , n H , the transfer volume, ∆ t V 0 , and the apparent molar expansibility at infinite dilution, E ∅ o , of AAGG in aqueous [CetPy][Sal] solution. The measured electrical conductivity was used to calculate the critical micelle concentration, cmc , and the relative thermodynamic quantities for the micellization of [CetPy][Sal] in an AAGG solution, i.e. the changes in the Gibbs free energy , the enthalpy, and the entropy. The binding constants between [CetPy][Sal] and AAGG were derived from UV–vis spectroscopic data . The aforementioned properties were analyzed in terms of the molecular interactions and structural changes existing in the studied ternary solutions of (AAGG +[CetPy][Sal]+water).
研究领域:
物理化学
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药用化学
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热力学
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光谱学
✓ 已验证
产品关联
DOI
高影响因子
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