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Nonisothermal Curing Kinetics and Properties of Tetraglycidyl-4, 4＇-Diaminodiphenylmethane/Polyimide

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材料科学与工程（中英文A版） 2011年第1X期1卷 29-36页

作者： Yongfen Xu Jiongxin Zhao Jialin Wu xinhai yu College of Chemical Engineering and Bioteehnology Donghua University Shanghai 201620 P. R .China College of Material Science and Engineering Donghua University Shanghai 201620 P. R .China Key Laboratory for Modification of Chemical Fibers & Polymer Materials Donghua University Shanghai 201620 P. R .China

The polyimide powder with fluorine atom and hydroxyl groups (PI) was synthesized and its chemical structure was characterized with FT-IR. The curing kinetics of N, N, N’, N’- tetraglycidyl -4,4’-diaminodiphenylmethane (TGDDM)/PI and TGDDM/PI/4,4"-diaminodiphenyl sulfone (DDS) were investigated by non-isothermal DSC, and determined by Kissinger, Ozawa and Crane methods. The results showed that the reaction energy of TGDDM/PI was higher than TGDDM/ PI/DDS. Then the reaction order, re-exponential factor and the reaction rate constant at peak temperature of the two systems were calculated. The cured TGDDM/PI system exhibited good thermal stability. The water absorption of the TGDDM/PI system was 0.49%.

关键词：固化反应动力学非等温DSC 聚酰亚胺 PI系统性能红外光谱特征二氨基二苯砜反应速率常数

Torque effect on vibration behavior of high-speed train gearbox under internal and external excitations

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Railway Engineering Science 2024年第2期32卷 229-243页

作者： yue Zhou Xi Wang Hongbo Que Rubing Guo xinhai Lin Siqin Jin Chengpan Wu yu Hou School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China CRRC Qishuyan Institute Co. Ltd.No.258Wuyi RoadQishuyanChangzhou 213011China Frontiers Science Center for Smart High-Speed Railway System Beijing Jiaotong UniversityBeijing 100044China

The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service *** paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was *** responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was ***,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was ***,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic *** results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating *** was also found that the torque affects the modal param-eter of the gearbox *** torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently.

关键词： High-speed train Gearbox Bench test Vibration behavior Modal identification

静态价格下的颠峰动态涨势下的深渊——我们距离房产周期的顶点还有多远?

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上海经济研究 2005年第2期17卷 37-40,89页

作者：余新海天勤证券研究所 200120

着眼于房产消费品、投资品兼备的二元性 ,本文从房产消费者的预算约束与房产投资者的预期投资收益率两个微观的维度 ,分析了当前中国房产定价是否已经偏离均衡价格的问题 ,并得出了中国当前房产已经接近周期顶峰的结论 ,而化解的关键是... 详细信息

着眼于房产消费品、投资品兼备的二元性 ,本文从房产消费者的预算约束与房产投资者的预期投资收益率两个微观的维度 ,分析了当前中国房产定价是否已经偏离均衡价格的问题 ,并得出了中国当前房产已经接近周期顶峰的结论 ,而化解的关键是能否将房价涨幅控制在人均可支配收入增速之内。

关键词：资产定价模型景气周期预算约束

Stretchable poly[2]rotaxane elastomers

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Fundamental Research 2024年第2期4卷 300-306页

作者： Kai Liu xinhai Zhang Dong Zhao Ruixue Bai Yongming Wang Xue Yang Jun Zhao Hao Zhang Wei yu Xuzhou Yan School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Chemical Engineering National Engineering Research Center for Dyeing and Finishing of TextilesDonghua UniversityShanghai 201620China

Mechanically interlocked polymers(MIPs)are promising candidates for the construction of elastomeric materials with desirable mechanical performance on account of their abilities to undergo inherent rotational and translational mechanical movements at the molecular ***,the investigations on their mechanical properties are lagging far behind their structural fabrication,especially for linear polyrotaxanes in ***,we report stretchable poly[2]rotaxane elastomers(PREs)which integrate numerous mechanical bonds in the polymeric backbone to boost macroscopic mechanical ***,we have synthesized a hydroxyfunctionalized[2]rotaxane that subsequently participates in the condensation polymerization with diisocyanate to form *** from the peculiar structural and dynamic characteristics of the poly[2]rotaxane,the representative PRE exhibits favorable mechanical performance in terms of stretchability(∼1200%),Young’s modulus(24.6 MPa),and toughness(49.5 MJ/m^(3)).Moreover,we present our poly[2]rotaxanes as model systems to understand the relationship between mechanical bonds and macroscopic mechanical *** is concluded that the mechanical properties of our PREs are mainly determined by the unique topological architectures which possess a consecutive energy dissipation pathway including the dissociation of host−guest interaction and consequential sliding motion of the wheel along the axle in the[2]rotaxane motif.

关键词： Polyrotaxanes Mechanically interlocked polymers Mechanically interlocked molecules Dynamic materials Elastomers

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严苛条件下承压系统安全阀技术

化工进展 2019年第1期38卷 145-154页

作者：涂善东于新海张健华东理工大学机械与动力工程学院承压系统与安全教育部重点实验室上海200237

安全阀作为承压系统主要的安全附件对保证化学与能源工业装置的安全运行起着举足轻重的作用。近年来,随着承压系统工作压力与温度环境等日益严苛,对安全阀性能也提出了更加精准与严苛的要求。为了探索先进安全阀的设计、制造与运维技术... 详细信息

安全阀作为承压系统主要的安全附件对保证化学与能源工业装置的安全运行起着举足轻重的作用。近年来,随着承压系统工作压力与温度环境等日益严苛,对安全阀性能也提出了更加精准与严苛的要求。为了探索先进安全阀的设计、制造与运维技术,本文概述了安全阀的研究现状和取得的重要技术进展,包括安全阀动作和排量性能的精准设计、安全阀密封设计、安全阀抗震设计、安全阀可靠性的精准设计、热态试验验证及安全阀本身的结构完整性保障和健康监测等,在此基础上,指出了今后亟待解决的若干科学技术问题,包括极端工况(高温、高压、地震、火灾等)流体流场下安全阀瞬态响应的计算模拟技术、极端工况下安全阀全性能试验装置和试验方法、精确测量安全阀流量系数的多尺度方法、智能安全阀技术、极端工况安全阀结构完整性评价技术。

关键词：安全阀设计试验抗震可靠性结构完整性

A novel integrated energy systems combining methanol reformed fuel cell with sodium ion battery

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Green Chemical Engineering 2021年第3期2卷 251-252页

作者： Haiying Che Ziyu Zhang xinhai yu John Shen Shan-Tung Tu Zi-Feng Ma Shanghai Electrochemical Energy Devices Research Centre Department of Chemistry EngineeringShanghai Jiao Tong UniversityShanghai200240China Zhejiang Natrium Energy Co.Ltd. Shaoxing312000China Palcan Energy Corporation BurnabyBCV5J 5H8Canada School of Mechanical Engineering East China University of Science and TechnologyShanghai200237China

Hydrogen safety in storage and transport is one of the major obstacles for the widespread adoption of hydrogen fuel cells,making it critical to assuage public concerns on the safety of compressed hydrogen *** in bountiful supply is a promising hydrogen energy ***,a novel MSR-HT-PEMFC system coupling the hydrogen production via methanol steam reforming(MSR)and energy generation via high temperature proton exchange membrane fuel cell(HT-PEMFC)was firstly introduced by ***-Feng Ma from Shanghai Jiaotong University and ***-Tung Tu from East China University of Science and Technology,in collaboration with Shanghai Palcan Energy *** MSRHT-PEMFC system eliminates the potential risks of compressed hydrogen storage.

关键词： methanol battery reforming

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高效液相色谱法测定特非那丁片溶出度

中国医院药学杂志 2000年第8期20卷 471-473页

作者：程斌刘启余心海中国人民解放军第457医院湖北武汉430012 湖北新洲县人民医院 430000

目的 :通过对国内 3个厂家生产的特非那丁片溶出度测定 ,考察其质量。方法 :转篮法 ,用高效液相色谱法检测 ,提取参数 (T50 、Td、m) ,并对参数进行相关性检验。结果 :不同厂家产品溶出参数差异显著。结论 :对国内厂家的特非那丁片有必... 详细信息

目的 :通过对国内 3个厂家生产的特非那丁片溶出度测定 ,考察其质量。方法 :转篮法 ,用高效液相色谱法检测 ,提取参数 (T50 、Td、m) ,并对参数进行相关性检验。结果 :不同厂家产品溶出参数差异显著。结论 :对国内厂家的特非那丁片有必要增加溶出度考察 ,以控制其质量。

关键词：特非那丁溶出度高效液相色谱法质量控制

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无溶剂耐高温环氧-酰亚胺基体树脂的制备

合成树脂及塑料 2015年第6期32卷 12-16页

作者：虞鑫海黄莉茜东华大学上海市201620

采用多官能环氧树脂、活性聚酰亚胺、环氧树脂活性稀释剂、固化剂和促进剂,制备了无溶剂耐高温环氧-酰亚胺基体树脂(ECPIM),并研究了其黏度、凝胶化时间、表观活化能、拉伸剪切强度、电容、介电损耗、接触角、表面能、吸水率等。结果表... 详细信息

采用多官能环氧树脂、活性聚酰亚胺、环氧树脂活性稀释剂、固化剂和促进剂,制备了无溶剂耐高温环氧-酰亚胺基体树脂(ECPIM),并研究了其黏度、凝胶化时间、表观活化能、拉伸剪切强度、电容、介电损耗、接触角、表面能、吸水率等。结果表明:ECPIM具有良好的固化反应活性,优异的黏接强度,240℃时的拉伸剪切强度高达24.2 MPa;频率为20 Hz^1 MHz时,ECPIM的电容值均较稳定,且介电损耗较低,介电性能优异;ECPIM具有较低的表面能(65.8 m J/m2)和吸水率(1.12%)。

关键词：环氧-酰亚胺基体树脂无溶剂耐高温拉伸性能吸水率

在涂层催化剂上甲醇水蒸气重整的本征动力学研究

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石油化工 2005年第11期34卷 1055-1059页

作者：袁彪于新海王正东涂善东华东理工大学机械与动力工程学院上海200237

使用环状模拟微型反应器,研究了在涂层催化剂上甲醇水蒸气重整的本征动力学.涂层催化剂为Cu50/Zn50[Ce5],在消除内外扩散影响的条件下,在478～508 K范围内进行甲醇水蒸气重整的实验;利用线性最小二乘法,由实验数据确定双速率动力学模型... 详细信息

使用环状模拟微型反应器,研究了在涂层催化剂上甲醇水蒸气重整的本征动力学.涂层催化剂为Cu50/Zn50[Ce5],在消除内外扩散影响的条件下,在478～508 K范围内进行甲醇水蒸气重整的实验;利用线性最小二乘法,由实验数据确定双速率动力学模型参数.甲醇重整反应速率常数为3.492×1011,活化能为99.937kJ/mol;甲醇分解反应速率常数为8.126×1011,活化能为121.571 kJ/mol.F统计检验的结果表明,所得本征动力学模型适用于涂层催化剂.

关键词：微型反应器本征动力学甲醇水蒸气重整氢燃料电池催化剂