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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
Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio
《结构与土木工程前沿(英文)》 2021年 第15卷 第6期 页码 1400-1414 doi: 10.1007/s11709-021-0779-8
关键词: aggregates non-destructive testing sand-to-aggregate volume ratio (s/a) maximum aggregate size (MAS)
陈积懋
《中国工程科学》 2000年 第2卷 第4期 页码 64-69
论述了检测复合材料和胶接结构不连续(缺陷)的新型多模综合无损检测技术。该技术以声与超声检测技术为基础,包含五种不同检测模式,用以检测复合材料与胶接结构的失粘、脱粘、分层、疏松、夹芯压皱及其他缺陷。它适用于复合材料与构件的制造、维修和使用现场。它的适用对象范围广泛,几乎覆盖了现有常用的复合材料和胶接结构。它的检测可靠性高,重复精度好。文章还讨论了组成多膜声学综合胶接检测仪的五种不同检测模式的原理,并从我们和国内外同行的大量实践经验出发,说明了综合无损检测技术的巨大发展前景。
Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene
CHEN Hanjia, SHI Xuhua, ZHU Yafei, ZHANG Yi, XU Jiarui
《化学科学与工程前沿(英文)》 2008年 第2卷 第1期 页码 102-108 doi: 10.1007/s11705-008-0018-z
关键词: polypropylene crystallization capacity attenuated hydrophilicity reflectance
Separation of gibberellic acid (GA3) by macroporous adsorption resins
WANG Ruifang, YANG Jialing, SHI Zuoqing, OU Lailiang
《化学科学与工程前沿(英文)》 2008年 第2卷 第2期 页码 171-175 doi: 10.1007/s11705-008-0025-0
关键词: industrial gibberellic adsorption capacity crystallization consistent
孙威
《中国工程科学》 2007年 第9卷 第7期 页码 7-17
讨论地震前兆有它自已的孕震物理模型,地震孕育全过程分为加载、相持、卸载、短临和临震5个阶段;多次震例证明,破坏性地震的孕震物理模型是会重复和再现的;提出了追踪地震前兆信息,循序渐进预报地震的分析方法,对地震预报的阶段性进行了实用性的划分,有希望实现对破坏性地震的预报。
Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He
《化学科学与工程前沿(英文)》 2017年 第11卷 第4期 页码 647-662 doi: 10.1007/s11705-017-1649-8
关键词: membrane distillation crystallization mathematics model nucleation separation hybrid process
Effects of a structurally related substance on the crystallization of paracetamol
Ali SALEEMI, I.I. ONYEMELUKWE, Zoltan NAGY
《化学科学与工程前沿(英文)》 2013年 第7卷 第1期 页码 79-87 doi: 10.1007/s11705-013-1308-7
关键词: acetaminophen metacetamol crystallization metastable zone width induction time supersaturation control
Interfacial induction and regulation for microscale crystallization process: a critical review
《化学科学与工程前沿(英文)》 2022年 第16卷 第6期 页码 838-853 doi: 10.1007/s11705-021-2129-8
关键词: interfacial crystallization heterogeneous nucleation supersaturation micro/nanostructure process control and intensification
The feasibility of coating by cooling crystallization on ibuprofen naked tablets
Fatima Mameri, Ouahiba Koutchoukali, Mohamed Bouhelassa, Anne Hartwig, Leila Nemdili, Joachim Ulrich
《化学科学与工程前沿(英文)》 2017年 第11卷 第2期 页码 211-219 doi: 10.1007/s11705-017-1619-1
关键词: coating solution crystallization ibuprofen tablets sucrose
Utilizing melt crystallization fundamentals in the development of a new tabletting technology
Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH
《化学科学与工程前沿(英文)》 2014年 第8卷 第3期 页码 346-352 doi: 10.1007/s11705-014-1443-9
关键词: phase separation melt crystallization tablets process optimization
Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom
Wen Zhang,Jack W. Szostak,Zhen Huang
《化学科学与工程前沿(英文)》 2016年 第10卷 第2期 页码 196-202 doi: 10.1007/s11705-016-1565-3
Preparation and crystallization kinetics of micron-sized Mg(OH)
Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU
《化学科学与工程前沿(英文)》 2013年 第7卷 第2期 页码 130-138 doi: 10.1007/s11705-013-1332-7
关键词: magnesium hydroxide precipitation micron-sized crystallization kinetics
Applications of the crystallization process in the pharmaceutical industry
Sohrab ROHANI
《化学科学与工程前沿(英文)》 2010年 第4卷 第1期 页码 2-9 doi: 10.1007/s11705-009-0297-z
Importance of emulsions in crystallization—applications for fat crystallization
Sandra PETERSEN, K. CHALEEPA, Joachim ULRICH
《化学科学与工程前沿(英文)》 2013年 第7卷 第1期 页码 43-48 doi: 10.1007/s11705-013-1309-6
关键词: emulsion fat crystallization phase change material emulsion fractionation emulsion solidification
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
Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio
期刊论文
Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene
CHEN Hanjia, SHI Xuhua, ZHU Yafei, ZHANG Yi, XU Jiarui
期刊论文
Separation of gibberellic acid (GA3) by macroporous adsorption resins
WANG Ruifang, YANG Jialing, SHI Zuoqing, OU Lailiang
期刊论文
Progress in membrane distillation crystallization: Process models, crystallization control and innovative
Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He
期刊论文
Effects of a structurally related substance on the crystallization of paracetamol
Ali SALEEMI, I.I. ONYEMELUKWE, Zoltan NAGY
期刊论文
The feasibility of coating by cooling crystallization on ibuprofen naked tablets
Fatima Mameri, Ouahiba Koutchoukali, Mohamed Bouhelassa, Anne Hartwig, Leila Nemdili, Joachim Ulrich
期刊论文
Utilizing melt crystallization fundamentals in the development of a new tabletting technology
Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH
期刊论文
Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom
Wen Zhang,Jack W. Szostak,Zhen Huang
期刊论文
Preparation and crystallization kinetics of micron-sized Mg(OH)
Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU
期刊论文