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Spatial Correlation in Typical Binary Polycondensation Systems: An Essential Extension of the Kirkwood-Buff Theory

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Chemical Research in Chinese Universities 2023年第6期39卷 985-991页

作者： gu fang LI Jiangtao HONG Xiaozhong WANG Haijun College of Chemistry and Materials Science Hebei UniversityBaoding 071002P.R.China College of Physical Science and Technology Hebei UniversityBaoding 071002P.R.China Chemical Biology Key Laboratory of Hebei Province Hebei UniversityBaoding 071002P.R.China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis Ministry of EducationHebei UniversityBaoding 071002P.R.China

We present the isothermal susceptibility(XT)for the typical binary polycondensation system of Af-Bg type,and relate XT to the weight-average degree of polymerization in terms of the Kirkwood-Buff(KB)*** investigation is based on a new expression of XT for mixtures,which is still expressed by the KB integrals(KBIs)but endowed with an explicit physical *** polymerization systems,it is proposed that the KBIs can be further decomposed according to whether there exists a bond between particles when conversions(extents of reaction)of functional groups are incorporated into the *** this way,XT is directly decomposed into its relevant components as *** is especially useful to reveal the relationship between local structures and average properties of various polymerization *** a consequence,the effect of polymerization on XT is greatly simplified in comparison with the free energy ***,we have provided a very simple method to carry out some thermodynamic properties of polymerization systems.

关键词： Isothermal compressibility Polycondensation Kirkwood-Buff theory Radial distribution function Spatial correlation

Epitaxial growth of Fe/Ag single crystal superlattices and their magnetic properties

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 71-76页

作者： Yu gu Fei Zeng fang Lv Yu-li gu Pei-yong Yang Feng Pan Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Single crystal Fe/Ag（001） superlattices with various periodicities were fabricated using ultrahigh vacuum evaporation deposition. It was found that single crystal bcc Fe layers and single crystal fcc Ag layers can epitaxially grow on a single crystal Ag buffer layer alternately, which was deposited on NaCl single crystal chips by ion beam assisted deposition. The magnetic measurements of the superlattices reveal an oscillation coupling between ferromagnetism and antiferromagnetism as a function of the Ag layer thickness. The oscillation period, which is 1 nm （5 Ag layers）, is in good agreement with the calculated values when the Ag thickness is greater than 1.5 nm. While the thickness of the Ag spacer layer decreases to 1 nm, the oscillation coupling varies from calculations, which can be attributed to the intermixing of the interlayers according to the annealing results.

关键词： Fe/Ag superlattices magnetization oscillating periodicity annealing

Structure of Solution of Colloid and Hydrogen Bonding Fluid Near a Semipermeable Membrane

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Chemical Research in Chinese Universities 2017年第2期33卷 248-254页

作者： ZHAO Meng CHEN Hanfei gu fang WANG Haijun College of Chemistry and Environmental Science Hebei University Baoding 071002 P. R. China Chemical Biology Key Laboratory of Hebei Province Hebei University Baoding 071002 P. R. China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis Ministry of Education Hebei University Baoding 071002 P. R. China

The local fluid structure of a solution consisting of colloid particles and hydrogen bonding（HB） fluid se-parated from pure solvent by a semipermeable membrane was investigated, where the colloid particles and HB fluidserve as solute and solvent, respectively. In this paper, the semipermeable membrane allows the passage of solventmolecules but not solute particles, and therefore, it provides a nano-confinement for colloid particles. The densityprofiles of the two species near the semipermeable membrane were determined via density functional theory（DFT）for classical fluids. Based on the predicted density profiles under various conditions, the effects of HB strength, func-tionality, total bulk density, density fraction and the size ratio of two species on the fluid structure were discussed. Asan application, the osmotic pressures of the system were also presented. It is shown that the local structure andosmotic pressure can be efficiently regulated by these factors due to the competition between the excluded volumeinteractions and the FIB interaction. The present results are expected to be helpful to study the osmotic phenomenaand relevant problems on the nanoscale.

关键词： Hydrogen bonding fluid Semipermeable membrane Osmotic pressure Density functional theory

Statistical theory for hydrogen bonding fluid system of A_aD_d type(II):Properties of hydrogen bonding networks

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Science China Chemistry 2007年第1期50卷 11-17页

作者： WANG HaiJun HONG XiaoZhong gu fang BA XinWu College of Chemistry and Environment Science Hebei UniversityBaoding 071002China International Center for Materials Physics Chinese Academy of SciencesShenyang 110016China College of Physics Science and Technology Hebei UniversityBaoding 071002China

Making use of the invariant property of the equilibrium size distribution of the hydrogen bonding clus- ters formed in hydrogen bonding system of AaDd type,the analytical expressions of the free energy in pregel and postgel regimes are *** the gel free energy and the scaling behavior of the number of hydrogen bonds in gel phase near the critical point are investigated to give the corre- sponding scaling exponents and scaling ***,some properties of intermolecular and in- tramolecular hydrogen bonds in the system,sol and gel phases are *** a result,the explicit relationship between the number of intramolecular hydrogen bonds and hydrogen bonding degree is obtained.

关键词： hydrogen bonding network gel phase scaling law

A Unified Theoretical Treatment on Statistical Properties of the Semi-batch Self-condensing Vinyl Polymerization System

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Chinese Journal of Polymer Science 2021年第11期39卷 1510-1520页

作者： fang gu Jiang-Tao Li Xiao-Zhong Hong Hai-Jun Wang College of Chemistry and Environment Science Hebei UniversityBaoding 071002China College of Physical Science and Technology Hebei UniversityBaoding 071002China Chemical Biology Key Laboratory of Hebei Province Hebei UniversityBaoding 071002China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis Ministry of EducationHebei UniversityBaoding 071002China

We present a novel generating function(GF)method for the self-condensing vinyl polymerization(SCVP)system with any initial distribution of preexisted *** a method was proven to be especially useful to investigate the semi-batch SCVP system allowing a sequence of feeding operations during the ***,the number-,weight-,and z-average molecular weights as well as dispersity index of hyperbranched polymers can be explicitly given,which are determined by predetermined feeding details and conversions in each polymerization *** analytical results are further confirmed by the corresponding Monte Carlo ***,the present GF method has provided a unified treatment to the semi-batch SCVP ***,hyperbranched polymers with desired properties can be prepared by designing feeding details and presetting conversions at each step based on the present GF method.

关键词： Self-condensing vinyl polymerization Semi-batch Generating function Statistical properties

An evaluation of moving shadow detection techniques

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Computational Visual Media 2016年第3期2卷 195-217页

作者： Mosin Russell Ju Jia Zou gu fang School of Computing Engineering and MathematicsWestern Sydney University

Shadows of moving objects may cause serious problems in many computer vision applications,including object tracking and object recognition. In common object detection systems, due to having similar characteristics, shadows can be easily misclassified as either part of moving objects or independent moving objects. To deal with the problem of misclassifying shadows as foreground, various methods have been introduced. This paper addresses the main problematic situations associated with shadows and provides a comprehensive performance comparison on up-todate methods that have been proposed to tackle these problems. The evaluation is carried out using benchmark datasets that have been selected and modified to suit the purpose. This survey suggests the ways of selecting shadow detection methods under different scenarios.

关键词： moving shadow detection problematic situations shadow features shadow detection methods

Phase Equilibria of Hydrogen Bonding Fluid in a Slit Pore with Broken Symmetry

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Chinese Journal of Chemical Physics 2015年第3期28卷 288-294,I0001页

作者： Xiao-yu Liu Jiang-tao Li fang gu Hai-jun Wang College of Chemistry and Environmental Science Hebei University Baoding 071002 China Chemical Biology Key Laboratory of Hebei Province Hebei University Baoding 071002 China Key Laboratory of Medical Chemistry and Molecular Diagnosis Ministry of Education BaodinE 071002 China

Phase equilibria of hydrogen bonding （HB） fluid confined in a slit pore with broken symmetry were investigated by the density functional theory incorporated with modified fundamental measure theory, where the symmetry breaking originated from the distinct interactions between fluid molecules and two walls of the slit pore. In terms of adsorption-desorption isotherms and the corresponding grand potentials, phase diagrams of HB fluid under various conditions are presented. Furthermore, through phase coexistences of laying transition and capillary condensation, the effects of HB interaction, pore width, fluid-pore interaction and the broken symmetry on the phase equilibrium properties are addressed. It is shown that these factors can give rise to apparent influences on the phase equilibria of confined HB fluid because of the competition between intermolecular interaction and fluid-pore interaction. Interestingly, a significant influence of broken symmetry of the slit pore is found, and thus the symmetry breaking can provide a new way to regulate the phase behavior of various confined fluids.

关键词： Hydrogen bonding fluid Broken symmetry Phase equilibria Density functional theory

Impact of an emergency department nursing intervention on continuity of care, self-care, and psychological symptoms

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World Journal of Psychiatry 2023年第12期13卷 1046-1052页

作者： Song Xu Yi-fang gu Ai-Hua Dong Department of Emergency Room The First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

BACKGROUND The emergency department plays a crucial role in providing acute care to *** interventions in this setting are essential for improving the continuity of care,enhancing patients’self-care abilities,and reducing psychological *** To evaluate the effect of nursing interventions in the emergency department on these indicators in an emergency *** A retrospective analysis was conducted on 120 patients admitted to the emergency department between January 2022 and May *** patients were divided into two groups:The control group(conventional nursing intervention)and the observation group(conventional nursing intervention+emergency department nursing intervention).The two groups were compared regarding continuity of care,self-care ability,psychological symptoms,and satisfaction with *** The emergency department nursing interventions significantly improved the continuity of care,enhanced patients’self-care abilities,and reduced psycho-logical symptoms such as anxiety and *** Nursing interventions in the emergency department positively impact continuity of care,self-care,and psychological ***,it is important to acknowledge the limitations of this study,including the small number of studies,variable methodological quality,and the heterogeneity of the study *** research should address these limitations and further explore the effects of different types of nursing interventions in the emergency ***,efforts should be made to enhance the application and evaluation of these interventions in clinical practice.

关键词： Emergency department Nursing interventions Continuity of care Self-care psychological symptoms

Influences of surface effects and large deformation on the resonant properties of ultrathin silicon nanocantilevers

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Chinese Physics B 2012年第1期21卷 363-373页

作者： Zhang Jia-Hong Li Min gu fang Liu Qing-Quan Jiangsu Key Laboratory of Meteorological Observation and Information Processing Nanjing University of Information Science&TechnologyNanjing 210044China College of Math&Physics Nanjing University of Information Science&TechnologyNanjing 210044China

The purpose of the present work is to quantify the influences of the discrete nature, the surface effects, and the large deformation on the bending resonant properties of long and ultrathin （100） silicon nanocantilevers. We accomplish this by using an analytical semi-continuum Keating model within the framework of nonlinear, finite deformation kinematics. The semi-continuum model shows that the elastic behaviors of the silicon nanocantilevers are size-dependent and surface- dependent, which agrees well with the molecular dynamics results. It also indicates that the dominant effect on the fundamental resonant frequency shift of the silicon nanocantilever is adsorption-induced surface stress, followed by the discrete nature and surface reconstruction, whereas surface relaxation has the least effect. In particular, it is found that a large deformation tends to increase the nonlinear fundamental frequency of the silicon nanocantilever, depending not only on its size but also on the surface effects. Finally, the resonant frequency shifts due to the adsorption-induced surface stress predicted by the current model are quantitatively compared with those obtained from the experimental measurement and the other existing approach. It is noticed that the length-to-thickness ratio is the key parameter that correlates the deviations in the resonant frequencies predicted from the current model and the empirical formula.

关键词： resonant properties elastic properties surface effects silicon nanocantilevers