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On the Scaling Law for Af Type Free Radical Homopolymerization

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Chinese Physics Letters 1999年第4期16卷 301-303页

作者： WANG Hai-jun ba xin-wu ZHAO Min LI Ze-sheng Department of Chemistry Hebei UniversityBaoding 071002 Institute of Theoretical Chemistry&State Key Laboratory of Theoretical and Computational Chemistry Jilin UniversityChangchun 130023

From the equilibrium number fraction distribution for Af type free radical homopolymerization,the asymptotic distribution and polymer moments near the gel point are *** a direct result of scaling transformation,ageneralized scaling law which characterizes the sol-gel transition is *** reveals that the curing of this type is in essence a phase transition process.

关键词： process. polymerization scaling

A Statistical Theory for Hydrogen Bonding Networks: One Component Case

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Chinese Physics Letters 2000年第1期17卷 16-18页

作者： WANG Hai-Jun ba xin-wu ZHAO Min LI Ze-Sheng Department of Chemistry Hebei UniversityBaoding 071002 Institute of Theoretical Chemistry and State Key Laboratory of Theoretical and Computational Chemistry Jilin UniversityChangchun 130023

The theory of reversible gelation is shown to be applicable to the hydrogen bonding system by analyzing their similarities in statistical *** size distribution of hydrogen bonding clusters,the gelation condition and the generalized scaling law can be obtained *** results show that such a system can undergo phase transition ***,a relationship between Gibbs free energy of forming hydrogen bond and conversions of groups is *** an example,the chemical shift of OH groups is considered.

关键词： process. bonding system

Statistical Parameters for Hydrogen Bonding Networks: One Component Case

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Chinese Physics Letters 2001年第6期18卷 764-766页

作者： WANG Hai-Jun HONG Xiao-Zhong ZHAO Min ba xin-wu Department of Chemistry Hebei UniversityBaoding 071002 Department of Physics Hebei UniversityBaoding 071002

based on the analysis of network structures formed by hydrogen bonds as the sol-gel phase transition takes place in a single component hydrogen bonding system,the theory of reversible gelation is applied to calculate some statistical parameters that determine many physical and chemical properties of the *** the numerical simulation of the number of active chains and dangling chains,the number of effective cross-linkages,the number of active and dangling mers and the modulus as a function of conversion are undertaken.

关键词： chains modulus bonding

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A_f+AB星型聚合体系的统计热力学

高等学校化学学报 2013年第9期34卷 2158-2163页

作者：田月兰巴信武河北大学化学与环境科学学院保定071002

应用统计力学和热力学原理研究了A f+AB星型聚合体系的性质.首先从两种不同的角度给出了与聚合反应相应的配分函数,并据此得到反应体系的平衡自由能、质量作用定律及数量分布函数,进而得到了体系的平衡状态方程和比热.在此基础上,以反... 详细信息

应用统计力学和热力学原理研究了A f+AB星型聚合体系的性质.首先从两种不同的角度给出了与聚合反应相应的配分函数,并据此得到反应体系的平衡自由能、质量作用定律及数量分布函数,进而得到了体系的平衡状态方程和比热.在此基础上,以反应体系的回转半径为例研究了溶剂效应对星型高分子空间尺度的影响.

关键词：星型聚合反应质量作用定律均方回转半径溶剂效应

The Role of Renewable Protocatechol Acid in Epoxy Coating Modification: Significantly Improved Antibacterial and Adhesive Properties

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Chinese Journal of Polymer Science 2024年第1期42卷 63-72,I0008页

作者： Ming-Xuan Chen Jin-Yue Dai Li-Yue Zhang Shuai-Peng Wang Jing-Kai Liu Yong-Gang wu xin-wu ba Xiao-Qing Liu School of Chemistry and Materials Science Hebei UniversityBaoding 071000China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Marine Materials and Related Technologies Chinese Academy of SciencesNingbo 315201China

It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is still a challenge because of the common complex design and synthesis. Herein, the bio-based monomer protocatechuic acid(PCA) was used as raw material, the catechol structure with high bonding and antibacterial properties was introduced into the flexible alkane segment of ethylene glycol diglycidyl ether(EGDE) through an efficient, and green method, and it was cured with isophorone diamine(IPDA) to prepare corresponding thermosets. The cured resins exhibited excellent allaround qualities, particularly in bonding and antibacterial. When 30% PCA was added to pure epoxy resin, the adhesion between substrate and coating increased from 4.40 MPa to 13.60 MPa and the antibacterial rate of coating against E. coli and S. aureus could approach 100%. All of this is due to the fact that the catechol structure present in PCA has the ability to interact with various substrates and alter the permeability of bacterial cell membranes. The architecture of this method offers a fresh approach to dealing with the issues of challenging raw material selection and complex synthesis techniques.

关键词： Epoxy coatings Thermosets Catechol structure Antibacterial High adhesion

Principal components of nuclear mass models

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 65-71页

作者： xin-Hui wu Pengwei Zhao Department of Physics Fuzhou UniversityFuzhou 350108China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

Principal component analysis(PCA)is employed to extract the principal components(PCs)present in nuclear mass models for the first *** effects from different nuclear mass models are reintegrated and reorganized in the extracted *** PCs are recombined to build new mass models,which achieve better accuracy than the original theoretical mass *** comparison indicates that using the PCA approach,the effects contained in different mass models can be collaborated to improve nuclear mass predictions.

关键词： nuclear mass principal component analysis nuclear models statistical methods

Dissipation-Driven Superradiant Phase Transition of a Two-Dimensional Bose-Einstein Condensate in a Double Cavity

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Chinese Physics Letters 2024年第6期41卷 44-48页

作者： Bo-Hao wu xin-xin Yang Yu Chen Wei Zhang Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Graduate School of China Academy of Engineering Physics Beijing 100193China Beijing Academy of Quantum Information Sciences Beijing 100193China

We study superradiant phase transitions in a hybrid system of a two-dimensional Bose–Einstein condensate of atoms and two cavities arranged with a tilt *** adjusting the loss rate of cavities,we map out the phase diagram of steady states within a mean field *** is found that when the loss rates of the two cavities are different,superradiant transitions may not occur at the same time in the two cavities.A first-order phase transition is observed between the states with only one cavity in superradiance and both in *** the case that both cavities are superradiant,a net photon current is observed flowing from the cavity with small decay rate to the one with large decay *** photon current shows a non-monotonic dependence on the loss rate difference,owing to the competition of photon number difference and cavity field phase *** findings can be realized and detected in experiments.

关键词： Einstein transitions decay

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超支化梯形共轭聚合物的合成与表征

化学学报 2010年第14期68卷 1454-1460页

作者：吴军玲武永刚巴信武河北大学化学与环境科学学院保定071002

采用"A2+B2+B3"方法,通过Pd(0)催化的Suzuki聚合反应制备了一系列的超支化梯形共轭聚合物.所制备的聚合物荧光发射均在蓝光发射区.随着支化度的增加,聚合物的荧光发射和紫外吸收均有蓝移的趋势.超支化结构在一定程度上抑制分子间的聚集... 详细信息

采用"A2+B2+B3"方法,通过Pd(0)催化的Suzuki聚合反应制备了一系列的超支化梯形共轭聚合物.所制备的聚合物荧光发射均在蓝光发射区.随着支化度的增加,聚合物的荧光发射和紫外吸收均有蓝移的趋势.超支化结构在一定程度上抑制分子间的聚集,使得聚合物在薄膜中的发射和吸收相对于溶液中的发射和吸收红移比较小.所制备的聚合物都表现出了良好的热稳定性,热分解温度都在320℃以上,DSC二次加热曲线在35～300℃之间没有玻璃化转变和其它的热力学过程.超支化共轭聚合物有望成为一种良好的蓝光材料.

关键词：梯形聚合物共轭聚合物超支化

Stability of the Stratification of Water Bodies in the North Passage of the Yangtze River Estuary based on the EFDC Model

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Journal of Ocean University of China 2024年第1期23卷 23-32页

作者： wu De’an LI xin WANG Yigang College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Tianjin Research Institute For Water Transport Engineering Tianjin 300456China

To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC *** the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical *** work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water *** model simulation results validate the formulae for the stratified stability discriminant during spring tides.

关键词： Yangtze Estuary North Passage EFDC model stratification stability salinity distribution