INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2021
·Vol. 22
·期 15
·8250
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IF 5.924
Shanmeiyu Zhang,Yanyan Zhang,Chongchong Wu,Hui Yang,Qiqi Zhang,Fuyi Wang,Jingyi Wang,Ian Gates,Jinben Wang
Although small water clusters (SWCs) are important in many research fields, efficient methods of preparing SWCs are still rarely reported, which is mainly due to the lack of related materials and understanding of the molecular interaction mechanisms. In this study, a series of functional molecules were added in water to obtain small water cluster systems. The decreasing rate of the half-peak width in a sodium dodecyl sulfate (SDS)–water system reaches ≈20% at 0.05 mM from17O nuclear magnetic resonance (NMR) results. Based on density functional theory (DFT) and molecular dynamics (MD) simulation calculation, it can be concluded that functional molecules with stronger negative electrostatic potential (ESP) and higher hydrophilicity have a stronger ability to destroy big water clusters. Notably, the concentrations of our selected molecule systems are one to two magnitudes lower than that of previous reports. This study provides a promising way to optimize aqueous systems in various fields such as oilfield development, protein stability, and metal anti-corrosion.Keywords:water cluster;functional molecule;molecular interaction
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Matter
·
2024
·
IF 17.3
Xiaotao Yang,Jia Zheng,Xianfeng Luo,Hongyan Xiao,Peijia Li,Xiaodong Luo,Ye Tian,Lei Jiang,Dong Zhao
Alcoholic beverages are conventionally classified by alcohol by volume (ABV) based on ethanol-water mixture (EWM) concentrations, which is regarded as empirical with little scientific explanation. Here, we find that contact angles of EWMs with different ethanol fractions on highly oriented pyrolytic graphite are non-linear but steplike, while the critical points at step edges surprisingly fit the distributions of ABV. High-frequency proton nuclear magnetic resonance and molecular dynamics confirm different ethanol-water clusters in EWMs, whose structures undergo transitions at the critical points and keep stable in step ranges. Detailed cluster structures contain symmetric tetrahedral and chain-like clusters, and the ratio of the latter increases with higher ethanol fraction, further characterized by attenuated total reflectance infrared spectroscopy. Influence of temperature on clusters probably accounts for preferable changes of “ethanol-like tastes” of low-ABV beers or white wine after cooling and high-ABV shochu or Chinese baijiu after heating.
研究领域:
化学
·
物理学
·
食品科学
✓ 已验证
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2022
·
IF 4.831
Xiao-Qi Jia,Yi Li,Liping Zhang,Yuqing Wu
The taste of different flavor liquor is multifarious, but the same brand liquor with different quality is truth. The essence of supramolecular ethanol–water clusters and their intrinsic structural differences in three kinds of Fenjiu are studied by two-dimensional correlation spectra (2D-COS) of fluorescence and Raman. The 2D-COS of fluorescence reveals the prominent emission peaks of three Fenjiu are apparently different. The central fluorescence peak of Fenjiu (a) is located at 330 nm, corresponding to the cluster of (H 2 O) m (EtOH) n . In Fenjiu (b), the emission peak appears near 310 nm, while those of Fenjiu (c) appear mainly near 310 and 373 nm, corresponding to the clusters of (H 2 O)(EtOH) n and (H 2 O) m (EtOH), respectively. Based on 2D-COS of Raman, the peak of Fenjiu (b) at 3440 cm −1 changes initially, indicating its disorder degree is getting higher with continuous dilution with water. However, along with the dilution of Fenjiu (a) and Fenjiu (c), the peak located near 3200 cm −1 changes in priority, indicating that the degree of association between ethanol and water is high, and the clusters formed there are stable. Therefore, this work provides the combined methods to distinguish different supramolecular sets in Fenjiu , applying liquor differentiation in the future.
研究领域:
食品科学
·
光谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
·
2019
·
IF 2.923
Xueqian Guan,Zhiyu Huang,Hongsheng Lu,Dejun Sun
Binary mixtures of water and organic solvents are described as the aqueous solutions of organic solvents, which are usually spatially heterogeneous on the scale of a few molecular sizes but homogeneous on longer length scales, that is, microheterogeneity. For the water–organic solvent binary mixtures with microheterogeneity, most organic solvents are miscible with water at any ratio. Interestingly, some slightly water-miscible organic solvents can also be used to prepare binary mixtures with microheterogeneity. In this study, N,N-dimethylcyclohexylamine (DMCHA) was used to prepare binary mixtures with microheterogeneity and CO2 switchability. With the help of conductivity, Fourier–transform infrared spectroscopy, ultraviolet–visible spectroscopy, and dynamic light scattering measurements, we found that water molecules are hydrogen-bonded together to form clusters over the water content range of 9 to 27 wt %, exhibiting microheterogeneity in the binary mixture. The size of the water clusters increases slightly with increasing water content. What is more, the DMCHA–water mixtures can be reversibly split into two phases by alternate bubbling of CO2 and N2, exhibiting excellent CO2 switchability. The binary mixtures can be used as reaction media for the synthesis of CaCO3 nanoparticles. Binary mixtures with microheterogeneity can also be formed under high salinity or high temperature conditions or be prepared using other slightly water-miscible organic solvents, opening up more interesting possibilities for binary mixtures with microheterogeneity.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Hongbing Wang,Yifei Yang,Shixiang Yu,Beibei Zhang,Junzhong Xie,Jun Chen,Dongping Wang,Bomin Feng,Changyin Zhong,Linsen Zhou,Wei Cui,Ding Ma,Yunxi Yao
Liquid-phase hydrogen isotopes exchange between hydrogen and water is a promising route for the hydrogen isotopes separation from water, catalyzed by the metal Pt with hydrophobic coating to surmount the flooding of reactive sites. However, poor water activation ability on Pt has limited the catalytic efficiency of Pt-based catalysts and hindered their application. Herein, we report a bifunctional Pt/ZSM-5 catalyst with hydrophobic modification by surface silylation for H 2 -HDO isotope catalytic exchange. The integration of metallic Pt and Brønsted acid (BA) sites in the microporous ZSM-5 boosts the catalytic efficiency of deuterium extraction by two orders of magnitude compared to commercial Pt-C at the optimum condition. In-situ spectroscopic and theoretical studies demonstrated that HDO-H 2 O preferentially adsorbs on BA sites (-Si-OH-Al) to form protonated water clusters stabilized by hydrogen-bonded network or to undergo the proton exchange to leave deuterium on zeolite framework as a new acidic site ([AlO 4 D]). Under the attractive interaction, the dissociated hydrogen on Pt clusters releases partial electrons to form positively-charged hydrogen, which further transfers to the [AlO 4 D] sites or protonated water clusters by interfacial spillover to produce the overcharging intermediates. These intermediates cleave their O-D bonds to form positively charged D, which ultimately spills back to Pt cluster and combines with the remaining electron to desorb in the form of HD. The synergistic effect between Pt and BA sites creates a new pathway of hydrogen transfer, which enables the more efficient hydrogen-water isotope exchange on the bifunctional Pt/ZSM-5 catalyst.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）