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The Preparation of the Carbosilane Dendrimers with Pentafluorophenyl Groups

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Chinese Chemical Letters 2006年第9期17卷 1159-1161页

作者： rui fang GUAN Chuan Jian ZHOU Sheng yu FENG School of Materials Science and Engineering Ji＇nan University Ji＇nan 250022 School of Materials Science and Engineering Shandong University Ji＇nan 250061 School of Chemistry and Chemical Engineering Shandong University Ji＇nan 250100

Polysiloxane was a good solvent for hydrosilation reaction of carbosilane dendrimers with pentafluorophenyl core and HSiMeE（CH2）3C6F5. A new kind of dendrimer with both pentafluorophenyl core and terminal groups was synthesized. The studies showed that with the increase of fluorination, the viscosity values of carbosilane dendrimers decreased.

关键词： Polysiloxane hydrosilation carbosilane dendrimer pentafluorobenzene low viscosity.

Ore-forming Fluid and Mineral Source of the Hongshi Copper Deposit in the Kalatage Area, East Tianshan, Xinjiang, NW China

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1769-1783页

作者： yu Mingjie WANG Jingbin MAO Qigui fang Tonghui ZHANG rui Beijing Institute of Geology for Mineral Resources Beijing 100012 School of the Earth Sciences and Resources China University of Geosciences Beijing 100083 China Non-ferrous Metals Resource Geological Survey Beijing 100012

The Hongshi copper deposit is located in the middle of the Kalatage ore district in the northern segment of the Dananhu-Tousuquan island-arc belt in East Tianshan, Xinjiang, NW China. This study analyses the fluid inclusions and H, O, and S stable isotopic compositions of the deposit. The fluid-inclusion data indicate that aqueous fluid inclusions were trapped in chalcopyrite-bearing quartz veins in the gangue minerals. The homogenization temperatures range from 108°C to 299°C, and the salinities range from 0.5% to 11.8%, indicating medium to low temperatures and salinities. The trapping pressures range from 34.5 MPa to 56.8 MPa. The δ^（18）O_（H_2O） values and δD values of the fluid range from -6.94‰ to -5.33‰ and from -95.31‰ to -48.20‰, respectively. The H and O isotopic data indicate that the ore-forming fluid derived from a mix of magmatic water and meteoric water and that meteoric water played a significant role. The S isotopic composition of pyrite ranges from 1.9‰ to 5.2‰, with an average value of 3.1‰, and the S isotopic composition of chalcopyrite ranges from -0.9‰ to 4‰, with an average value of 1.36‰, implying that the S in the ore-forming materials was derived from the mantle. The introduction of meteoric water decreased the temperature, volatile content, and pressure, resulting in immiscibility. These factors may have been the major causes of the mineralization of the Hongshi copper deposit. Based on all the geologic and fluid characteristics, we conclude that the Hongshi copper deposit is an epithermal deposit.

关键词： ore-forming fluid H-O-S isotope Hongshi copper deposit Kalatage area East Tianshan

Failure analysis of AZ31 magnesium alloy sheets based on the extended GTN damage model

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1198-1207页

作者： rui-ze Wang Zhang-hua Chen yu-jie Li Chao-fang Dong School of Mathematics and Physics University of Science and Technology Beijing Xi’an Research Institute Co. Ltd.China Coal Technology & Engineering Group Crop. School of Material Engineering University of Science and Technology Beijing

Based on the Gurson-Tvergaard-Needleman （GTN） model and Hill＇s quadratic anisotropic yield criterion, a combined experimental-numerical study on fracture initiation in the process of thermal stamping of Mg alloy AZ31 sheets was carried out. The aim is to predict the formability of thermal stamping of the Mg alloy sheets at different temperatures. The presented theoretical framework was implemented into a VUMAT subroutine for ABAQUS/EXPLICIT. Internal damage evolution due to void growth and coalescence developed at different temperatures in the Mg alloy sheets was observed by scanning electron microscopy （SEM）. Moreover, the thermal effects on the void growth, coalescence, and fracture behavior of the Mg alloy sheets were analyzed by the extended GTN model and forming limit diagrams （FLD）. Parameters employed in the GTN model were determined from tensile tests and numerical iterative computation. The distribution of major and minor principal strains in the specimens was determined from the numerical results. Therefore, the corresponding forming limit diagrams at different stress levels and temperatures were drawn. The comparison between the predicted forming limits and the experimental data shows a good agreement.

关键词： magnesium alloys failure analysis microstructure anisotropy stamping

商丘市91例新型冠状病毒肺炎流行病学特征分析

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实用预防医学 2020年第8期27卷 916-918页

作者：刘利容许世禄余瑞芳李红星商丘市疾病预防控制中心河南商丘476000

目的了解商丘市新型冠状病毒肺炎(简称新冠肺炎,COVID-19)的流行病学特征,为下一步疫情防控工作提供依据。方法对截至2020年3月4日商丘市报告的91例新冠肺炎确诊病例的流行病学特征进行描述,同时对临床特点和病原学检测结果进行分析。... 详细信息

目的了解商丘市新型冠状病毒肺炎(简称新冠肺炎,COVID-19)的流行病学特征,为下一步疫情防控工作提供依据。方法对截至2020年3月4日商丘市报告的91例新冠肺炎确诊病例的流行病学特征进行描述,同时对临床特点和病原学检测结果进行分析。结果商丘市91例新冠肺炎确诊病例中,输入性病例44例(48.35%);发病年龄以18~59岁为主,占83.52%;人际传播主要在家庭中发生;临床分型以普通型为主,占65.93%;治愈率96.70%,病死率为3.30%;经两次及以上核酸检测确诊者占15.39%;治愈出院后核酸复检阳性4例(4.55%)。结论商丘市新冠肺炎疫情防控工作取得阶段性成果,外防输入是今后疫情防控工作的重点。

关键词：新型冠状病毒肺炎流行病学特征确诊病例核酸检测

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新型冠状病毒肺炎出院患者核酸复检阳性分析

实用预防医学 2021年第2期28卷 150-152页

作者：刘利容许世禄李红星余瑞芳商丘市疾病预防控制中心河南商丘476000

目的了解新型冠状病毒肺炎(简称新冠肺炎)治愈患者出院后14 d内核酸复检阳性率,分析复检阳性影响因素和传播风险,为有效管理出院患者提供依据。方法对86例出院患者的随访信息和核酸检测结果进行分析,计算出院后14 d内的核酸复检阳性率,... 详细信息

目的了解新型冠状病毒肺炎(简称新冠肺炎)治愈患者出院后14 d内核酸复检阳性率,分析复检阳性影响因素和传播风险,为有效管理出院患者提供依据。方法对86例出院患者的随访信息和核酸检测结果进行分析,计算出院后14 d内的核酸复检阳性率,分析性别、年龄、感染来源、临床严重程度、病程和住院时间等因素与复检阳性的统计学关联。结果 86例出院患者均无发热、乏力、干咳等新冠肺炎相关症状,8例(9.30%)患者核酸复检阳性;性别、年龄、感染来源、临床严重程度与出院后核酸复检阳性无统计学关联(P>0.05);病程和住院时间与核酸复检阳性有统计学关联(P<0.05);共追踪8例核酸复检阳性患者的密切接触者20人,未发现感染者。结论病程和住院时间为出院后核酸复检阳性的影响因素,建议出院患者进行14 d的隔离管理。

关键词：新型冠状病毒肺炎出院患者核酸检测病程住院时间

Rapid and reversible Na deposition onto Al nanosheet arrays

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Journal of Energy Chemistry 2022年第11期31卷 1-7,I0002页

作者： fang Tang Rongqing Xia Dong Chen yu Yao Lin Liu yuezhan Feng Xianhong rui Yan yu School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006GuangdongChina Hefei National Research Center for Physical Sciences at the Microscale Department of Materials Science and EngineeringNational Synchrotron Radiation LaboratoryCAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefei 230026AnhuiChina Key Laboratory of Materials Processing and Mold(Ministry of Education) Zhengzhou UniversityZhengzhou 450002HenanChina

Sodium metal battery(SMB)is regarded as a promising candidate for next-generation high-energy battery due to high theoretical capacity and abundant natural ***,the growth of sodium dendrites and large volume expansion during the processes of sodium plating and stripping seriously restrict the practical application of ***,a three-dimensional skeleton of aluminum nanosheet arrays(Al NSARs)is constructed by a facile etching approach to achieve rapid and reversible Na plating/*** Al NSARs with large geometric specific surface and plentiful cavities can provide rich active nucleation sites,reduce local current density and accommodate Na volume change,which lead to uniform deposition of sodium with dendrite-free *** a result,Na plating/stripping on Al NSARs can stably operate over 650 cycles at 2 mA cm^(-2)/2 mAh cm^(-2)with average Coulombic efficiency(CE)of 100.0%and low potential polarization of 27 ***,the full cell of Na_(s)V_(2)(PO_(4))_(3)||Al NSARs@Na can run for over 1800 cycles at a high rate of *** superior properties,combined with relatively low cost and weight of Al,enable our AlNSARs to begreat prospect for practical applications.

关键词： Sodiummetal battery Sodiummetal anode Three-dimensional skeleton Al nanosheet arrays Dendrite-freebehavior

Review on the study of metallurgical process engineering

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1253-1263页

作者： rui-yu Yin Central Iron and Steel Research Institute Beijing 100081China

After nearly one hundred years of research, metallurgy(metallurgical science and engineering) has gradually become a system with three levels of knowledge:(1) micro metallurgy at the atomic/molecular scale,(2) process metallurgy at the procedure/device, and(3) macrodynamic metallurgy at the full process/process group. Macro-dynamic metallurgy development must eliminate the concept of an "isolated system" and establish concepts of "flow," "process network," and "operating program" to study the "structure–function–efficiency" in the macrodynamic operation of metallurgical manufacturing processes. It means considering "flow" as the ontology and observing dynamic change by"flow" to solve the green and intelligent potential of metallurgical enterprises. Metallurgical process engineering is integrated metallurgy, toplevel designed metallurgy, macro-dynamic operated metallurgy, and engineering science level metallurgy. Metallurgical process engineering is a cross-level, comprehensive, and integrated study of the macro-dynamic operation of manufacturing processes. Metallurgical process engineering studies the physical nature and constitutive characteristics of the dynamic operation of steel manufacturing process, as well as the analysis-optimization of the set of procedure functions, coordination-optimization of the set of procedures' relations, and reconstruction-optimization of the set of procedures in the manufacturing process. The study establishes rules for the macro operation of the manufacturing process, as well as dynamic and precise objectives of engineering design and production operation.

关键词： metallurgical process engineering cross-level comprehensive integration macro-dynamic operation new branch of metallurgy

Modeling,simulations,and optimizations of gallium oxide on gallium-nitride Schottky barrier diodes

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Chinese Physics B 2021年第2期30卷 457-461页

作者： Tao fang Ling-Qi Li Guang-rui Xia Hong-yu yu School of Microelectronics Southern University of Science and TechnologyShenzhen 518055China Department of Materials Engineering the University of British ColumbiaVancouverBritish ColumbiaV6T1Z4Canada

With technology computer-aided design(TCAD)simulation software,we design a new structure of gallium oxide on gallium-nitride Schottky barrier diode(SBD).The parameters of gallium oxide are defined as new material parameters in the material library,and the SBD turn-on and breakdown behavior are *** simulation results reveal that this new structure has a larger turn-on current than Ga2O3 SBD and a larger breakdown voltage than Ga N ***,to solve the lattice mismatch problem in the real epitaxy,we add a Zn O layer as a transition *** simulations show that the device still has good properties after adding this layer.

关键词： technology computer-aided design(TCAD) gallium oxide(Ga2O3) gallium nitride(GaN) Schottky barrier diode(SBD)

Cu(0) Wire-mediated Single-electron Transfer-living Radical Polymerization of Oligo(ethylene oxide) Methyl Ether Acrylate by Selecting the Optimal Reaction Conditions

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Chinese Journal of Polymer Science 2019年第11期37卷 1130-1141页

作者： Liang Ding Juan Li rui-yu Jiang Ling-fang Wang Wei Song Lei Zhu Department of Polymer and Composite Material School of Materials Engineering Yancheng Institute of Technology Yancheng 224051 China Roy & Diana Vagelos Laboratories Department of Chemistry University of Pennsylvania Philadelphia PA 19104-6323 USA Jiangsu Collaborative Innovation Center for Ecological Building Material and Environmental Protection Equipments Yancheng Institute of Technology Yancheng 224051 China School of Chemistry and Materials Science Hubei Engineering University Hubei Collaborative Innovation Center of Conversion and Utilization for Biomass Resources Xiaogan 432000 China

The efficient Cu(0) wire-catalyzed single-electron transfer-living radical polymerization (SET-LRP) in organic solvents and mixtures of the organic solvents with water has been thoroughly investigated. 01igo(ethylene oxide) methyl ether acrylate was used as an exemplar oligomer monomer to determine the optimum polymerization conditions for rapid, controlled, and quantitative production of well-defined polymers. The effects of Cu(0)-wire length (12.5 or 4.5 cm), ligand type (tris(dimethylaminoethyl)amine, Me6-TREN, or tris(2-aminoethyl)amine, TREN), and solvent type (dipolar aprotic solvents, cyclic ethers, alcohol, or acetone) on the polymerization have been evaluated. Kinetic experiments were performed for all polymerizations to assess the "living" behavior of each system employed. Importantly, TREN could be used as a replacement for Me6-TREN in Cu(0) wire-catalyzed SET-LRP of oligomer monomer, which probably provides the most economical and efficient methodology since TREN is 80 times less expensive than Me6-TREN. The high chain-end fidelity of resulting polymer was experimentally verified by thiol-Michael addition reaction at the a-Br chain end and subsequent chain extension with methyl acrylate.

关键词： Single-electron transfer-living radical polymerization Oligo(ethylene oxide) methyl ether acrylate Kinetics of polymerization Modification