检索结果-南通市图书馆

Structure and Dynamics of Confined Polymer Melts from Attractive Interaction to Repulsive Interaction Between Polymer and Smooth Wall

引用

Chemical Research in Chinese Universities 2015年第3期31卷 477-483页

作者： LI Sijia ZHANG Wanxi yao weiguo SHI Tongfei College of Materials Science and Engineering Jilin University Changchun 130022 P.R.China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P.R.China College of Materials Science and Engineering Jilin University Changchun 130022 P.R.China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P.R.China

We studied the static and dynamic properties of unentangled polymer chains which have a variable strength of interaction with the confining smooth walls by means of the lattice Monte Carlo simulation based on the bond-fluctuation model, that is, investigated the wall-polymer interactions which systematically vary from attraction to repulsion. A critical value of attractive potential（ewe） is found to be -0.6kilT, and only below it can the adsorption layer of monomers be formed near the wall. At the critical point of attraction ewe, attractive interaction counterba- lances the wall-polymer excluded volume effect, which minimizes the confinement effects on both chain dimension and mobility. Influences on both chain dimension and mobility increase with the increasing of either attraction or repulsion imposed by the walls. Despite of the nature and strength of the wall-polymer interaction, with the decrease of film thickness, configurations more parallelly aligned and flattened are adopted by confined chains, and a systematic trend of deceleration is found. Variations of chain dynamics with both film thickness and wall-polymer interaction can be well explained by the corresponding changes in the confinement of the nearest-neighboring particles that surround the chains. Besides, the thickness of the interfacial layer inside polymer films, where chains adopt a flattened ＂pancake＂ shape, is about two times the bulk radius of gyratioia and independent of the wall-polymer interaction.

关键词： Confinement effect Wall-polymer interaction Critical point of attraction Lattice Monte Carlo simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Synthesis and Electrochemical Performance of Co3O4/Graphene

引用

Chemical Research in Chinese Universities 2014年第4期30卷 650-655页

作者： WANG Hongzhi SHI Yulei LI Zixuan ZHANG weiguo yao Suwei Department of Applied Chemistry School oJ Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China

Co3O4/reduced graphene oxide composites were synthesized via a simple electrochemical method from graphene oxide and Co（NO3）2·6H2O as raw ***3O4 nanoparticles with sizes of around 30-50 nm were distributed on the surface of graphene nanosheets confirmed by scanning electron microscopy and transmission electron *** properties of Co3O4/graphene composite were tested by cyclic voltammetry,galvanostatic charge-discharge,and electrochemical impedance *** Co3O4/reduced graphene oxide composite was used as the pseudocapacitor electrode in the 2 mol/L NaOH aqueous electrolyte *** Co3O4/reduced graphene oxide composite electrode exhibited a specific capacitance of 357 F/g at a current density of 0.5 A/g in a three-electrode system.72％ of capacitance was retained when the current density increased to 3 A/*** Co3O4/reduced graphene oxide composite prepared electrodes show a high rate capability and excellent long-term *** 1000 cycles of charge and discharge,the capacitance is still maintained 87％ at a current density of 1 A/g,indicating that the composite is a oromising alternative electrode material used for supercapacitors.

关键词： Cobalt oxide Graphene Composite Electrochemical preparation Supercapacitor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

维持性血液透析继发性甲旁亢患者的舌象改变与客观指标相关分析

引用

中国中西医结合肾病杂志 2024年第4期25卷 310-313页

作者：姚卫国程瑶左慧萍刘琨李丽王浩梁永平上海健康医学院附属金山区中心医院肾内科上海200540 上海中医药大学附属普陀医院肾内科上海200060

目的:探讨维持性血液透析(maintenance hemodialysis,MHD)继发性甲旁亢(secondary hyperparathyroidism,SHPT)患者舌象分布规律的相关性,旨在从中医学角度认识、治疗本病提供新的参考依据。方法:选取2020年06月—2022年06月上海健康医... 详细信息

目的:探讨维持性血液透析(maintenance hemodialysis,MHD)继发性甲旁亢(secondary hyperparathyroidism,SHPT)患者舌象分布规律的相关性,旨在从中医学角度认识、治疗本病提供新的参考依据。方法:选取2020年06月—2022年06月上海健康医学院附属金山区中心医院血液透析中心SHPT患者89例,收集患者基本临床资料及生化指标,记录患者舌象,分析SHPT患者舌象分布规律的相关性。结果:(1)SHPT患者舌象分布舌质颜色以淡白舌出现的比例最高,其次是红舌、青紫舌及淡红舌,舌体形态方面以齿痕舌和裂纹舌的比例最高,舌苔特征方面苔色以白苔居多,薄苔为主。(2)SHPT患者的舌质颜色与患者总胆固醇和低密度脂蛋白差异有统计学意义(P<0.05)。(3)SHPT患者的舌苔与患者血红蛋白、红细胞、红细胞比容、Kt/V、URR差异有统计学意义(P<0.05)。结论:SHPT患者舌象分布舌质颜色可作为判断病情变化的一项参考依据。

关键词：维持性血液透析继发性甲旁亢舌象分布客观指标

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation and optical absorption of InAs nanocrystal-embedded thin films

引用

Chinese Science Bulletin 1999年第3期44卷 210-214页

作者： Jianzhong Shi Kaigui Zhu weiguo yao Juhui Jia Zhixiang Cheng Lide Zhang Acad Sinica Inst Solid State Phys Hefei 230031 Peoples R China Suzhou Univ Dept Phys Suzhou 215006 Peoples R China

InAs-SiO2 nanocrystal-embedded films were prepared by using radio-frequency cosputtering. The growth behavior of InAs in the composite film has been studied by a transmission electron microscope. It has been found that with the increasing substrate temperature, InAs in the matrix undergoes transitions from an initial dispersed phase to a fractal structure of the InAs phase, then to nucleation, and finally to grain growth. Large blueshift of the optical absorption edges of the films was observed from the optical absorption spectra. The relationship between the blueshift of optical absorption edge and the average size of the nanocrystals has been explained by the effective-mass approximation.

关键词： nanocrystal-embedded thin films radio-frequency cosputtering optical absorption quantum confinement.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Shaking table test on a tunnel-group metro station in rock site under harmonic excitation

引用

Frontiers of Structural and Civil Engineering 2024年第9期18卷 1362-1377页

作者： Ruozhou LI weiguo HE Xupeng yao Qingfei LI Dingli ZHANG Yong YUAN Department of Geotechnical Engineering Tongji UniversityShanghai 200092China China Railway Liuyuan Group Co. Ltd.Tianjin 300308China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China

A tunnel-group metro station built in rock site is composed of a group of *** tunnels and their interconnections can show inconsistent responses during an *** study investigates the dynamic responses of such a metro station in a rock site,by shaking table *** lining structures of each tunnel and surrounding rock are modeled based on the similitude law;foam concrete and gypsum are used to model the ground-structure system,keeping relative stiffness consistent with that of the prototype.A series of harmonic waves are employed as excitations,input along the transverse and longitudinal direction of the shaking *** discrepant responses caused by the structural irregularities are revealed by measurement of acceleration and strain of the *** characteristics are identified by the transfer function method in white noise *** test results show that the acceleration response and strain response of the structure are controlled by the *** particular,the acceleration amplification effect at the opening section of the station hall is more significant than that at the standard section under transverse excitation;the amplification effect of the structural opening is insignificant under longitudinal excitation.

关键词： metro station tunnel-group shaking table test harmonic excitation dynamic response

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Investigation on the Initial Stage of Film Growth in Situ

引用

Journal of Materials Science & Technology 1994年第6期10卷 451-454页

作者： Zhenzhong QI Guopin DU Hanqi KE and weiguo yao(Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China) Inst of Solid State Physics Hefei China

The initial stage of Ag film growth on Cu(100). Ta(100) and Ta(110) single crystals as well as YBaCuO on Si single crystal covered by Pd was investigated in situ by means of LAS 600 surface analysis system with a sputtering source in sample preparation chamber. The results show that the initial state for Ag / Cu(100) film growth is typical S-K model, for Ag / Ta(100) and Ag / Ta(110)they have the same S-K characteristics, but due to the different surface energies of two crystalline planes. there is some difference for Ag / Ta (100) and Ag / Ta(110). YBCO sputterjng process is rather complex and Cu is the first element appearing in the film.

关键词： Ta Investigation on the Initial Stage of Film Growth in Situ Ag Cu

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Temperature-Dependent Tearing Behavior of Rubber Materials:Characterization and Modeling

引用

Acta Mechanica Solida Sinica 2024年第2期37卷 316-326页

作者： Qinyuan yao Feilong Zhang Pan Dong Ziyuan Zhao Yi He weiguo Li Liming Chen State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China College of Aerospace Engineering Chongqing UniversityChongqing400044China

With the increasingly widespread application of rubber in many fields,there is a growing demand for quantitative characterization of temperature-dependent mechanical properties in high-temperature service *** critical tearing energy is an important criterion for determining whether rubber materials will experience tearing instability,while tear strength is a key parameter for rubber materials to resist *** is necessary to quantitatively characterize their evolution with *** theoretical research mainly relies on fitting a large amount of experimental data,which is not convenient for engineering ***,in this work,a temperature-dependent critical tearing energy model is firstly developed based on the force-heat equivalence energy density *** model considers the equivalent relationship between the critical tearing energy required for crack instability propagation and the thermal energy stored in the rubber *** is demonstrated that our model has higher prediction accuracy when compared to other ***,combining with the Griffith fracture theory,temperature-dependent tear strength models applicable to three different crack modes are separately *** models are validated using experimental data for Mode I opening cracks and ModeⅢtearing cracks,and good consistency is ***,a quantitative analysis of the influence of elastic modulus on tear strength at different temperatures is *** work provides a reliable way for predicting temperature-dependent tearing instability behavior and offers beneficial suggestions for improving the tear strength of rubber materials at different temperatures.

关键词： Temperature-dependent Critical tearing energy Tear strength Rubber Theoretical model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Influence of Al-doping on electroluminescence of silicon-based films

引用

Chinese Science Bulletin 2001年第24期46卷 2043-2045页

作者： WU Xuemei YE Chunnuan ZHUGE Lanjian DONG Yemin TANG Naiyun YU Yuehui NING Zhaoyuan yao weiguo Department of Physics Suzhou UniversitySuzhou 215006China Ion Beam Laboratory Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050China

A series of Al-doped silicon-rich silica (AlSiO) composite films have been prepared by a dual ion beam co-sputtering method with a Al, Si and SiO2 composite target. The content of Al and Si in the films can be adjusted by changing the surface area of Al and Si of the target. Visible electroluminescence (EL) from the samples is found to have only one luminescence band peaked at 510 nm (2.4 eV). Experimental results show that the doping of Al is beneficial to reducing the onset voltage and to increasing the intensity of EL.

关键词： Al-doped silicon-based films EL.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hall Effect of an Oriented Superconducting YBa_(2)Cu_(3)O_(y) Film

引用

Chinese Physics Letters 1991年第10期8卷 541-543页

作者： HE Zhenhui SHA Jian WANG Shunxi CHENG Xiang'ai ZHOU Guien ZHANG Qirui SHI Wangzhou yao weiguo QI Zhenzhong Department of Physics and*Structure Research LaboratoryUniversity of Science and Technology of ChinaHefei 230026 Department of Physics Zhejiang Universityj Hangzhou 310027 Department of Physics Zhongshan UniversityGuangzhou 510275 Institute of Solid State Physics Academia SinicaHefei 230031

A superconducting YBa_(2)Cu_(3)O_(y) thin film,which is well oriented at(001)direction and in which no grain boundary is observed in the resolution limit of scanning electron microscope micrograph,is selected for the Hall effect measurement from 80 to 220 K under a magnetic field of 3 T.A very narrow and negative peak of the Hall voltage(V_(H))is found in the superconducting£nuisition region.A linear dependence of the carrier concentration fnjjJ on temperature is found in the normal *** appearance of such a negative peak is attributed to the intrinsic anisotropy of the Hall coefficient(Rn)related to the direction of the applied field and current.

关键词： grain narrow attributed

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

AN EXPERIMENTAL INVESTIGATION ON ADHESION OF IRON IN CONTACT WITH IRON AND COPPER

引用

Chinese Physics Letters 1987年第5期4卷 209-212页

作者： SUN Jiansan QI Zhenzhong LIU Ling yao weiguo Institute of Solid State Physics Academia SinicaHefei

Fe in contact with Fe and Cu was-investigated in a vacuum of 10^(7) Pa using a pin sample to contact with a flat *** adhesion bond force and adhesive strength have been *** adhesive strength of Fe-Cu and Fe-Fe are 130±20kg/mm^(2) and 70±10kg/mm^(2) at 298K,respectively,These strong interactions arise from the chemical bonding,instead of Van der Waals interaction.

关键词： interaction strength bonding

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：