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电中性固体表面上多条肽链的吸附过程——粗粒化模拟研究 Research
裘若桑, 肖杰, 陈晓东
《工程(英文)》 2020年 第6卷 第2期 页码 185-194 doi: 10.1016/j.eng.2018.12.012
李剑峰,刘茂,隋晓琳
《中国工程科学》 2007年 第9卷 第6期 页码 88-93
城市化进程的加快导致公共场所人群聚集事故时有发生,试图用泊松分布来描述一段时间内事故发 生次数及其对应的概率,进而推导出事故灾害频率的定量模型运用F-N图就可以分析公共场所人群聚集的社会风险。以公共场所 部分事故统计为参考数据,描述使用该模型的步骤,结果表明该模型具有一定的合理性和准确性。
来自157个国家的高中生聚集在一起共同应对工程技术领域的14项重大挑战之一——获取清洁的水资源
Joe A. Sestak Jr.
《工程(英文)》 2017年 第3卷 第5期 页码 583-584 doi: 10.1016/J.ENG.2017.04.022
多智能体协作与博弈展望:挑战、技术和应用 Perspective
刘瑜1,李徵2,姜智卓2,何友1
《信息与电子工程前沿(英文)》 2022年 第23卷 第7期 页码 1002-1009 doi: 10.1631/FITEE.2200055
茂金属催化剂催化烯烃聚合反应的研究 ——聚合物的聚集行为和热性能 Letter
吴长江, Minqiao Ren, Liping Hou, Shuzhang Qu, Xinwei Li, Cui Zheng, Jian Chen, 王伟
《工程(英文)》 2023年 第30卷 第11期 页码 93-99 doi: 10.1016/j.eng.2023.07.001
Olefin solution polymerization can be used to obtain high-performance polyolefin materials that cannot be obtained via other polymerization processes. Polyolefin elastomers (POE) are a typical example. Due to cost, only a few linear α-olefins (e.g., 1-butene, 1-hexene, and 1-octene) are used as comonomers in solution polymerization in industry. However, α-olefin comonomers with other structures may have different effects on polymerization in comparison with common linear ones. Moreover, the properties of the corresponding materials may differ significantly. In this work, copolymers of ethylene with linear and end-cyclized α-olefins are synthesized using a metallocene catalyst. The copolymerization of ethylene with linear α-olefins results in a higher turn-over frequency (TOF) and lower incorporation than copolymerization with end-cyclized α-olefins, which may indicate that end-cyclized α-olefins have a higher coordination probability and lower insertion rate. In this reaction, the comonomer is distributed randomly in the polymer chain and efficiently destroys crystallization. End-cyclized α-olefins exhibit a much stronger crystallization destructive capacity (CDC) in the copolymer than linear α-olefins, possibly because linear α-olefins act mainly in the radial direction of the main chain of the polymer, while end-cyclized α-olefins act mainly in the axial direction of the main chain.
关键词: Metallocene catalyst Ethylene copolymerization Comonomer distribution Crystallization destructive capacity
标题 作者 时间 类型 操作
茂金属催化剂催化烯烃聚合反应的研究 ——聚合物的聚集行为和热性能
吴长江, Minqiao Ren, Liping Hou, Shuzhang Qu, Xinwei Li, Cui Zheng, Jian Chen, 王伟
期刊论文
谭梦薇:基于高校垃圾分类的学生集体意愿调研及碳排放核算(2020年7月11日)
2022年05月19日
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