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A study of cavitation nucleation in pure water using molecular dynamics simulation

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Chinese Physics B 2022年第11期31卷 395-403页

作者： Hua Xie Yuequn Xu Cheng Zhong School of water Resources and Hydropower Engineering Wuhan UniversityWuhan 430072China Hangzhou water Resources and Hydropower Survey and Design Institute Co. LtdHangzhou 310016China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

To discover the microscopic mechanism responsible for cavitation nucleation in pure water,nucleation processes in pure water are simulated using the molecular dynamics *** nucleation is generated by uniformly stretching the system under isothermal conditions,and the formation and development of cavitation nuclei are simulated and discussed at the molecular *** processes of energy,pressure,and density are analyzed,and the tensile strength of the pure water and the critical volume of the bubble nuclei are *** results show that critical states exist in the process of cavitation *** the critical state,the energy,density,and pressure of the system change abruptly,and a stable cavitation nucleus is produced if the energy barrier is broken and the critical volume is *** pressure and water density are the key factors in the generation of cavitation *** the critical state is surpassed,the liquid is completely ruptured,and the volume of the cavitation nucleus rapidly increases to larger than 100 nm^(3);at this point,the surface tension of the bubble dominates the cavitation nucleus,instead of intermolecular *** negative critical pressure for bubble nucleation is-198.6 MPa,the corresponding critical volume is 13.84 nm^(3),and the nucleation rate is 2.42×10^(32)m^(-3)·s^(-1)in pure water at 300 *** has a significant effect on nucleation:as the temperature rises,nucleation thresholds decrease,and cavitation nucleation occurs earlier.

关键词： cavitation nucleation pure water molecular dynamics tensile strength

Ion Product of pure water Characterized by Physics-Based water Model

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Chinese Journal of Chemical Physics 2016年第2期29卷 167-170,I0001页

作者：揭斌斌蕯支唐厦门大学物理系厦门361005 中国科学院北京100864

pure water has been characterized for nearly a century, by its dissociation into hydronium （H3O）1＋ and hydroxide （HO）1- ions. As a chemical equilibrium reaction, the equilibrium constant, known as the ion product or the product of the equilibrium concentration of the two ion species, has been extensively measured by chemists over the liquid water temperature and pressure range. The experimental data have been nonlinear least-squares fitted to chemical thermodynamic-based equilibrium equations, which have been accepted as the industrial standard for 35 years. In this study, a new and statistical-physics-based water ion product equation is presented, in which, the ions are the positively charged protons and the negatively charged proton-holes or prohols. Nonlinear least squares fits of our equation to the experimental data in the 0-100℃ pure liquid water range, give a factor of two better precision than the 35-year industrial standard.

关键词： Solid state physics Liquid state chemistry pure water Ion product Positiveproton Negative proton-hole or prohol

Studies of water V. Five Phonons in Protonic Semiconductor Lattice Model of pure Liquid water

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Journal of Semiconductors 2017年第7期38卷 1-17页

作者： Binbin Jie Chihtang Sah Department of Physics Xiamen University Xiamen 361005 China Chinese Academy of Sciences Beijing 100864 China

We report physics based confirmation（~1% RMS deviation）, by existing experimental data, of protonprohol（proton-hole） ion product（p H） and mobilities in pure liquid water（0-100℃, 1-atm pressure） anticipated from our melted-ice Hexagonal-Close-Packed（H_2O）_4Lattice Model. Five phonons are identified.（1） A propagating protonic phonon（520.9 meV from lone-pair-blue-shifted stretching mode of isolated water molecule） absorbed to generate a proton-prohol pair or detrap a tightly-bound proton.（2） Two（173.4 and 196.6 meV） bending-breathing protonic-proholic or protonic phonons absorbed during de-trapping-limited proton or proton-prohol mobilities.（3）Two propagating oxygenic-wateric Debye-Dispersive phonons（30.3 and 27.5 meV） absorbed during scatteringlimited proton or proton-prohol mobilities.

关键词： solid, soft and liquid material physics pure water point-mass positive proton and negative prohol pH proton-ion product and mobilities phonon scattering and detrapping-trapping of propagating-localized protons and prohols

Studies of water Ⅵ. One-Band,Two-Band and Three-Band,Trappy,Protonic,Semiconductor Lattice Models for pure Liquid water

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Journal of Semiconductors 2018年第11期39卷 1-7页

作者： Binbin Jie Tianhui Jie Chihtang Sah Department of Physics Xiamen University American Physical Society US Institution applied Department of Physics Xiamen University Chinese Academy of Sciences

This report adds three protonic semiconductor models to explain the "abnormally" high electrical conductivity of pure liquid water characterized by the three industrial consensus parameters, the ion product(or pH)and the two ion mobilities. Existence of long-range order in fluid water under numerous daily conditions led us to extend the 1933 Bernal-Fowler hexagonally close packed crystalline Ice Lattice to model liquid water as Melted Ice. Protonic kinetic energy band and bound(trap) pictures provide semiconductor-physics based new models of these three parameters. They are extrapolatable engineered-models for developing novel biological, chemical, electrical, mechanical and medical applications of liquid water.

关键词： solid and soft-fluid-liquid materials physics pure water point-mass positive proton and negativeprohol proton-ion product (pH) and mobilities propagating-and-localized phonon scattering anddetrapping-trapping of propagating-and-localized protons and prohols Protonic Fermionic Bosonsand Bosonic Fermions

Quantitative Formation Ultra-Stable Molecular Host via Hydrazone in 100% water Without Template

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Quantitative Formation Ultra-Stable Molecular Host via Hydra...