新型环保防老剂在苯乙烯-丁二烯-苯乙烯嵌段共聚物中的应用研究

研究新型环保防老剂X和L在苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)中的应用效果。结果表明:以复配型防老剂L替代现用防护体系264/TNPP用于SBS中,胶样的氧化诱导期延长,抗黄变性和加工热稳定性提高,生产成本降低;防老剂L的最佳用量为0.6份。     

斜拉-悬吊协作体系桥的颤振稳定性研究

运用多模态颤振有限元分析方法 ,分别从悬索的矢跨比、吊跨比、斜拉索索面布置形式、边跨辅助墩的设置以及桥面主梁构成等设计参数着手 ,对主跨 14 0 0m的斜拉 -悬吊协作体系桥进行了颤振稳定性分析 ,指出了影响斜拉 -悬吊协作体系桥颤振稳定性的关键设计参数 ,并从抗风性能角度探讨了斜拉 -悬吊协作体系桥的合理结构型式。     

影响大跨径悬索桥颤振的非线性因素研究

随着桥梁跨径的增大 ,各种非线性因素对大跨径悬索桥颤振特性的影响将不容忽视。在线性颤振分析方法的基础上 ,考虑风速的空间非均匀分布、结构以及作用于结构上的气动力随结构变形的非线性变化影响因素 ,建立了大跨径桥梁的三维非线性颤振分析方法。以某悬索桥为例 ,进行了考虑风速空间非均匀分布、结构动力特性以及气动力随结构变形的非线性变化等因素的颤振分析 ,揭示了各种非线性因素对大跨径悬索桥颤振影响的机理和规律     

不同防护体系的星形溶聚丁苯橡胶耐老化性能研究

研究3种防老剂对星形溶聚丁苯橡胶(SSBR)耐老化性能的影响.结果表明:在SSBR中加入少量防老剂即可获得良好的热氧稳定性;采用防老剂X或Z的SSBR热氧稳定性较好;防老剂X在SSBR中的应用效果较好,其适宜用量为0.4份.     

橡胶助剂在合成橡胶中的应用概况

介绍硫化剂、促进剂和活性剂等硫化体系助剂,抗氧剂、物理防老剂和化学防老剂等防护体系助剂,增粘剂、增塑剂、均匀剂和分散剂等加工助剂的特点及其在合成橡胶中的应用概况。合成橡胶用橡胶助剂应向环保、高效、多功能、低成本方向发展。     

基于判断限的高灵敏度γ峰筛选方法

天然放射性核素是全面禁止核试验条约(Comprehensive Nuclear-Test-Ban Treaty,CTBT)放射性核素台站气溶胶样品的主要放射性成分,CTBT相关放射性核素的弱γ峰处于这些天然放射性核素形成的复杂高本底基线上。针对高环境本底基线上弱γ峰检测难题,提出了一种基于判断限的γ峰筛选方法,结合二阶导数寻峰法,显著提高了HPGeγ能谱中弱γ峰的准确检出率。使用IMS核素台站获取的HPGeγ能谱对该峰筛选方法进行测试,结果显示:峰识别率为97.4%,峰误识别率仅为10.4%。     

Recent ICRF coupling experiments on EAST

Recent ion cyclotron resonance frequency(ICRF) coupling experiments for optimizing ICRF heating in high power discharge were performed on EAST. The coupling experiments were focus on antenna phasing and gas puffing, which were performed separately on two ports of the ion cyclotron resonance heating(ICRH) system of EAST. The antenna phasing was performed on the I-port antenna, which consists of four toroidally spaced radiating straps operating in multiple phasing cases; the coupling performance was better under low wave number ∣k_‖∣(ranging from 4.5 to 6.5). By fuelling the plasma from gas injectors, placed as uniformly spaced array from top to bottom at each side limiter of the B-port antenna, which works in dipole phasing, the coupling resistance of the B-port antenna increased obviously.Furthermore, the coupling resistance of the I-port antenna was insensitive to a smaller rate of gas puffing but when the gas injection rate was more than a certain value(1021 s~(-1)), a sharp increase in the coupling resistance of the I-port antenna occurred, which was mainly caused by the toroidal asymmetric boundary density arising from gas puffing. A more specific analysis is given in the paper.