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Isospin effects on intermediate mass fragments at intermediate energy-heavy ion collisions

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Nuclear Science and Techniques 2022年第5期33卷 68-77页

作者： Li Li fang-yuan Wang Ying-Xun Zhang China Institute of Atomic Energy P.O.Box 275(18)Beijing 102413China Department of Physics and Technology Guangxi Normal UniversityGuilin 540101China

In this study,we investigated the isospin properties of intermediate mass fragments(IMFs)for the central collisions of^(112,124)Sn+^(112,124)Sn at a beam energy of50 MeV per nucleon using an improved quantum molecular dynamics model(ImQMD)coupled with a sequential decay model(GEMINI).Three observables were analyzed:(1)the average center-of-mass kinetic energy per nucleonof fragments as a function of their charge number Z;(2)the average neutron number to proton number ratio(/Z)of fragments with a given charge number Z as a function of their center-of-mass kinetic energy per nucleon(Ec.m./A);and(3)the average total neutron number to total proton number ratio(ΣN/ΣZ)and double ratio(DR(N/Z))of IMFs with Z=3-8 as a function of their center-of-mass kinetic energy per nucleon Ec.m./*** calculations revealed that the sensitivity of the isospin properties of IMFs relative to the stiffness of the symmetry energy remains even after sequential *** comparing the calculations ofΣN/ΣZ and DR(N/Z)with the data,it was found that the soft symmetry energy,i.e.,γ=0.5,is favored.

关键词： Symmetryenergy Intermediatemass fragments Isospin effects

Numerical study on flexural behaviors of steel reinforced engineered cementitious composite(ECC) and ECC/concrete composite beams

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Science China(Technological Sciences) 2014年第3期57卷 637-645页

作者： yuan fang PAN JinLong WU YuFei Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education Southeast University Department of Civil and Architectural Engineering City University of Hong Kong

Engineered cementitious composite(ECC)is a class of high performance cementitious composites with pseudo strain-hardening behavior and excellent crack control *** of concrete with ECC can largely reduce the cracking and durability problems associated with brittleness of *** this paper,a simplified constitutive model of the ECC material was applied to simulate the flexural behaviors of the steel reinforced ECC and ECC/concrete composite beams with finite element *** simulation results are found to be in good agreement with test results,indicating that the finite element model is reasonably accurate in simulating the flexural behaviors of the steel reinforced ECC flexural *** effects of the ECC modulus,ECC tensile ductility,ECC thickness and ECC position on flexural behaviors in terms of ultimate moment,deflection and the maximum crack width of the steel reinforced ECC or ECC/concrete composite beam are hence evaluated.

关键词： engineered cementitious composite(ECC) constitutive model flexural behavior finite element

Global Existence of Small Solutions for Cubic Quasi-linear Klein-Gordon Systems in One Space Dimension

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1085-1102页

作者： Dao yuan fang Ru Ying XUE Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China

In this paper, we consider a system of two cubic quasi-linear Klein-Gordon equations with different masses for small, smooth, compactly supported Cauchy data in one space dimension. We show that such a system has global existence when the nonlinearities satisfy a convenient null condition. Our results extend the global existence proved by Sunagawa recently under the non-resonance assumption to that under the resonance assumption.

关键词： Cubic Quasi-linear Klein-Gordon systems One space dimension Global existence Asymptotic behavior

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政务服务极简化的风险及其演化逻辑

广西师范大学学报（哲学社会科学版） 2025年第1期61卷 33-45页

作者：袁方成魏玉欣华中师范大学政治与国际关系学院湖北武汉430079

作为应对社会复杂性的治理策略,政务服务极简化旨在通过数字技术优化政务流程以进一步提升服务效率和效能。然而,“技术—组织”复合驱动机制孕育多重风险:包括事务负担超载、数据泄露和网络攻击在内的系统崩溃、选择性服务与民众情绪... 详细信息

作为应对社会复杂性的治理策略,政务服务极简化旨在通过数字技术优化政务流程以进一步提升服务效率和效能。然而,“技术—组织”复合驱动机制孕育多重风险:包括事务负担超载、数据泄露和网络攻击在内的系统崩溃、选择性服务与民众情绪激化以及地区数字化“孤岛效应”放大等。究其原因,在于技术与组织之间的短板相互掣肘推动风险的聚合与叠加:技术赋能锁定组织陷入“负能”循环、技术嵌入后形成对组织的“反操控”、技术工具理性排斥组织公共价值以及技术“锦标赛”刺激地方拉大差距等。因此,推进政务服务极简化需要更审慎考虑和细致规划,在追求技术治理优势的同时,平衡技术创新与组织效能,确保技术进步与社会公正的兼容性和可持续性。

关键词：政务服务极简化驱动机制技术治理风险

Analysis on the development status of DNA storage based on papers and patents

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High Technology Letters 2021年第2期27卷 218-225页

作者： Zheng Yanning yuan fang An Shudi Inslilule of Scientific and Technical Information of China Beijing 100038P.R.China

DNA storage as a disruptive technology is expected to solve the problem of massive data *** on bibliometric analysis of DNA storage related papers and patents,this paper analyzes the development trend of DNA storage *** results show that DNA technology is still in the development stage,in which only a small number of researchers are *** is the global leading country of DNA storage *** universities and companies in USA have played an important role in promoting DNA storage *** is second only to USA in the number of DNA storage related papers or ***,in terms of patents layout,Chinese institutions don’t have sufficient intention of opening up the global market in the application of DNA *** there have been several breakthrough advances in DNA storage,there are still many challenges to be solved.

关键词： DNA storage information digital data bibliometric analysis 0 Introduction

On Free Boundary Problem for the Non-Newtonian Shear Thickening Fluids

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Journal of Partial Differential Equations 2021年第1期34卷 14-41页

作者： WANG Shu yuan fang College of Applied Sciences Beijing University of TechnologyBeijing 100124China China Everbright Bank Beijing 100054China

The aim of this paper is to explore the free boundary problem for the NonNewtonian shear thickening *** fluids not only have vacuum,but also have strong nonlinear *** this paper,a class of approximate solutions is first constructed,and some uniform estimates are obtained for these approximate ***,the existence of free boundary problem solutions is proved by these uniform estimates.

关键词： On free boundary problem the non-Newtonian shear thickening fluids vacuum

In Vitro Interaction of Nicotine and Hemoglobin under Liver Cell Metabolizing Condition

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Chinese Chemical Letters 2001年第5期12卷 449-452页

作者： Yan WANG Hong fang SUN Hai fang WANG yuan fang LIU Department of Technical Physics Peking UniversityBeijing 100871

The in vitro interaction of nicotine and hemoglobin (Hb) in a metabolizing System was studied by spectroscopy assays. Visible spectra showed two isobestics, and fluorescence spectra showed static quenching with increasing of nicotine dose. Meanwhile, the CD spectra intensity reduced, showing the conformation of Hb varied markedly through the interaction. All these results suggested that the interaction of nicotine or its metabolites and Hb might do harm to physicological function of Hb.

关键词： Nicotine hemoglobin visible absorption fluorescence CD

Influence of Cr_(2)_(3)content on viscosity and rheological behavior of Cr_(2)O_(3)-containing slags

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Journal of Iron and Steel Research International 2022年第4期29卷 601-611页

作者： fang yuan Zheng Zhao Yan-ling Zhang Tuo Wu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The rheological behavior of Cr_(2)_(3)-containing slags was investigated using a rotating cylinder viscometer and the solid fraction and phases of Cr_(2)_(3)in molten slags were also calculated and observed at different ***,the viscosities of CaO–SiO2–Cr_(2)_(3)(–10%Al2O3)slags were measured from 1703 to 1953 K and the influence of Cr_(2)_(3)content on the viscosity and rheological behavior of molten slags was *** calculation revealed that the solid fraction of the molten slags varied with the Cr_(2)_(3)content and maximum temperature,and the fluid properties transitioned from Newtonian to non-Newtonian behavior when the solid fraction reached 5%.Moreover,the increase in Cr_(2)_(3)content led to an increase in the viscosity as the slags displayed Newtonian flow characteristics and a decrease in the viscosity when slags exhibited non-Newtonian flow *** viscosity results of Cr_(2)_(3)-containing slag from 1703 to 1953 K and from 1703 to 1813 K were also discussed with the morphologies.

关键词： Viscosity Rheology behavior Cr_(2)_(3)-containing slag Morphology

The dynamic response and damage models of rebar reinforced polymer slabs subjected to contact and near-field explosions

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Defence Technology（防务技术） 2023年第10期28卷 330-342页

作者： Hao-nan Zhao Hong-yuan fang Xiao-hua Zhao Yellow River Laboratory Zhengzhou UniversityZhengzhou450001China

Non aqueous reactive polymer materials produced by the reaction of isocyanate and polyol have been widely used in infrastructure construction,which may be subjected to explosion loads during complex service *** blast response of composite materials is a crucial aspect for applications in engineering structures potentially subjected to extreme *** this work,damage caused to rebar reinforced polymer slabs by surface explosive charges was studied experimentally and numerically.A total of 6 field tests were carried out to investigate the performances of the failure modes of rebar reinforced polymer slabs under contact and near-field *** influence of explosive quantity(10-40 g)and stand-off distances(0-20 cm)at the damage modes were *** results show that the failure modes of rebar reinforced polymer slabs under near-field explosion mainly were bending and surface spalling,while under the impact of contact explosion,the failure modes were craters of the top surface,spalling of the bottom surface,and middle ***,a detailed fully coupled model was developed and validated with the test *** influences of explosive quantity and slab thickness on rebar reinforced polymer slabs under contact explosion were *** on this,the calculation formula between breach diameter,explosive quantity,and slab thickness is fitted.

关键词： Reinforced polymer slab Numerical investigations Empirical prediction Damage models