The interaction of water with small alcohols can be used as a model for understanding hydrophobic solvation of larger and more complex amphiphilic molecules. Despite its apparent simplicity, water/ethanol mixtures show important anomalies in several of their properties, like specific heat or partial molar volume, whose precise origin are still a matter of debate. Here we report high-resolution thermal conductivity, compressibility, and IR-spectroscopy data for water/ethanol solutions showing three distinct regions of solvation, related to changes in the H-bond network. Notably, the thermal conductivity shows a surprising increase of ≈3.1% with respect to pure water at dilute concentrations of ethanol (x = 0.025), which suggests a strengthening of H-bond network of water. Our results prove that the rate of energy transfer in water can be increased by hydrophobic solvation, due to the cooperative nature of the H-bond network.
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http://dx.doi.org/10.1039/d0cp03778h | DOI Listing |
J Colloid Interface Sci
December 2024
Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou, Fujian 350002, PR China; Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian 350108, PR China; Fujian College, University of Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China. Electronic address:
The reversibility and stability of aqueous zinc-ion batteries (AZIBs) are largely limited by free-water-induced side reactions (e.g., hydrogen evolution and zinc corrosion) and negative zinc dendrite growth.
View Article and Find Full Text PDFProtein Sci
January 2025
Faculty of Physics, University of Duisburg-Essen, Duisburg, Germany.
Proteins of obligate halophilic organisms have an unusually high number of acidic amino acids, thought to enable them to function in multimolar KCl environments. Clarifying the molecular scale mechanisms by which this occurs is relevant for biotechnology, to enable enzymatic synthesis of economically important small molecules in salty environments and other environments with low water activity. Previous studies have suggested that acidic amino acids are necessary at high salt concentration to keep the proteins hydrated by competing with the ions in solution for available water (the "solvent-only" model).
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Centre for Innovative Food (CiFOOD), Department of Food Science, Aarhus University, Agro Food Park 48, Aarhus N 8200, Denmark; Food Technology Area, Department of Agricultural Engineering, University of Valladolid, Spain. Electronic address:
Building up from our previous findings on deep eutectic solvents (DES) as reaction promoters for the acetylation of pure wheat starch, the current work explored combinations of reaction time, temperature and acetic anhydride: bread molar ratios to acetylate macromolecules within bread particles relying solely on macromolecule solvation and the slightly basic environment provided by the eutectic mixture. High degree of substitution with acyl groups (DS, 0.73-1.
View Article and Find Full Text PDFNano Lett
December 2024
Department of Mechanical Engineering, State Key Laboratory of Tribology in Advanced Equipment (SKLT), Tsinghua University, Beijing 100084, China.
Solvation force, stemming from the interfacial liquid structure, dominates the short-range interfacial interaction within a few nanometers across broad fields such as battery, lubrication, and colloid. However, achieving a quantitative understanding of solvation force for an aqueous system has remained elusive for decades, with the widely used contact value theory underestimating solvation force due to inherent assumptions. In this work, inspired by the flow field of liquid when two confining surfaces approach each other, we proposed a parameter-free expression for the solvation force acting on atomically smooth surfaces, quantitatively related to the energy barrier when liquid molecules are squeezed out from confinement.
View Article and Find Full Text PDFJ Chem Inf Model
December 2024
Institute of Environmental Science and Engineering (IESE), School of Civil and Environmental Engineering (SCEE), National University of Sciences and Technology (NUST), H-12, Islamabad 44000, Pakistan.
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