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Solvent Vapor Annealing Induced Polymorphic Transformation of Polybutene-1

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Chinese Journal of Polymer Science 2016年第9期34卷 1141-1149页

作者： hua-feng shao ya-ping ma 聂华荣贺爱华 Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics (Ministry of Education) School of Polymer Science and Engineering Qingdao University of Science and Technology Qingdao 266042 China

Solvent annealing is a facile method for changing the aggregated microstructure and physical properties of polymer materials. In this paper, we addressed the effects of solvent vapor annealing, including chloroform and water vapor, on the polymorphic transformation in both hot-pressed film and electrospun nonwoven of isotactic polybutene-1 （PB-1） by means of in situ Fourier transform infrared spectroscopy （FTIR）. The pretty rapid transition rate caused by the increased motion of molecular chains under chloroform vapor is associated with a lowest crystallinity. Also, a decreased crystallinity with the crystal transition occurred in electrospun nonwovens resulting from the relaxation of the stretched molecular chains into amorphous state rather than realignment into crystal form I predominating the crystal transition process.

关键词： Polybutene-1 Crystal transformation Solvent vapor annealing.

Differential Polymorphic Transformation Behavior of Polybutene-1 with Multiple Isotactic Sequences

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Chinese Journal of Polymer Science 2020年第2期38卷 164-173,I0007页

作者： Ya-Ping Ma Wei-Ping Zheng Chen-Guang Liu hua-feng shao hua-Rong Nie Ai-hua He Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics (Ministry of Education) Qingdao University of Science and Technology

For the solid-solid transformation from form Ⅱ to form Ⅰ of isotactic polybutene-1(iPB),the temperature dependence of form Ⅰ nucleation and growth was deemed to control the transformation ***,the relationship between formⅠ formation and form Ⅱ disappearance in the transformation process is not *** this work,the spontaneous crystal transformation from form Ⅱ to Ⅰ of iPB with 81 mol%mmmm sequence concentration is studied firstly by tracking the two processes,the decay of form Ⅱ and the yielding of form Ⅰ in a wide range of temperature spanning from 0℃ to 50℃ and in a long transformation time ranging from 5 min to 65 days with in situ FTIR and *** the literature reports,the decay rate of form Ⅱ is firstly found to be lower than the yielding rate of form Ⅰ at all studied temperatures,especially at low transition *** is attributed to the amorphous chains which locate near crystal lamella participating into the nucleation of form Ⅱ.The regular chain folding and growth of i PB form Ⅰ from amorphous chains containing short isotactic sequences also lead to an increase in crystallinity of form Ⅰ compared with that of initial form Ⅱ crystallized at 60℃.An increase in the annealing temperature results in decrease in crystallinity and increase in lamellae thickness of i PB formⅠ.

关键词： Polybutene-1 Polymorphic transformation Isotactic sequence Crystallinity Lamellae thickness

Fabrication of Trans-1,4-polyisoprene Nanofibers by Electrospinning and Its Crystallization Behavior and Mechanism

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Chinese Journal of Polymer Science 2016年第7期34卷 797-804页

作者： hua-feng shao zhi-lu li 贺爱华 chen-guang liu wei yao Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics Ministry of Education Qingdao University of Science and Technology Qingdao 266042 China

Trans-1,4-polyisoprene（TPI） nanofibers have been fabricated successfully through electrospinning *** the control of electrospinning parameters, highly crystallized TPI fresh fibers composed mainly of β phase were produced. Morphology and diameter of TPI nanofibers can be controlled by adjusting the electrospinning conditions. The in situ observations of FTIR spectra revealed that the crystallinity of the TPI fibers decreased with aging. While for TPI nanofibers aging at 45 °C for 24 h, a decrease in crystallinity as well as β to a transformation was observed with aging and these changings happened in the first 50 h during aging. The mechanism for β-TPI formation during electrospinning process and the reduced crystallinity with aging were proposed.

关键词： Electrospinning Trans-1 4-polyisoprene Crystallization Transformation βphase

Polymerization Kinetics of Propylene with the MgCl_(2)-Supported Ziegler-Natta Catalysts——Active Centers with Different Tacticity and Fragmentation of the Catalyst

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Chinese Journal of Polymer Science 2021年第1期39卷 70-80,I0006页

作者： Wei-Ping Zheng Ya-Ping Ma Da-Lin Du Ai-hua He hua-feng shao Chen-Guang Liu Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics(Ministry of Education)School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China

The catalytic activity and stereospecificity of olefin polymerization by using heterogeneous TiCl_(4)/MgCl_(2) Ziegler-Natta(Z-N) catalysts are determined by the structure and nature of active centers, which are mysterious and fairly controversial. In this work, the propylene polymerization kinetics under different polymerization temperatures by using Z-N catalysts were investigated through monitoring the concentration of active centers [C*] with different tacticity. SEM was applied to characterize the catalyst morphologies and growing polypropylene(PP) particles. The lamellar thickness and crystallizability of PP obtained under different polymerization conditions were analyzed by DSC and SAXS. The PP fractions and active centers with different tacticity were obtained with solvent extraction fractionation method. The catalytic activity, active centers with different tacticity and propagation rate constant kp, fragmentation of the catalyst, crystalline structure of PP are correlated with temperature and time for propylene polymerizations. The polymerization temperature and time show complex influences on the propylene polymerization. The higher polymerization temperature(60 ℃) resulted higher activity, kp and lower [C*], and the isotactic active centers Ci* as the majority ones producing the highest isotactic polypropylene(iPP) components showed much higher kp when compared with the active centers with lower stereoselectivity. Appropriate polymerization time provided full fragmentation of the catalyst and minimum diffusion limitation. This work aims to elucidate the formation and evolution of active centers with different tacticity under different polymerization temperature and time and its relations with the fragmentation of the PP/catalyst particles, and provide the solutions to the improvement of catalyst activity and isotacticity of PP.

关键词： Polypropylene Catalytic activity Active center Catalyst fragmentation

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大学英语线上资源的整合利用与教学实践研究

教育理论与实践 2021年第36期41卷 53-56页

作者：滑少枫河套学院外国语言文学系内蒙古巴彦淖尔015000

当前,我国大学英语线上资源整合利用与教学实践中存在学生利用线上资源开展自主学习的能力有待提高,学生主体性和个性化学习需求尚未满足,英语听说教学的线上资源利用有待进一步提升,线上资源整合与教学应用的范围有待延伸和拓展,线上... 详细信息

当前,我国大学英语线上资源整合利用与教学实践中存在学生利用线上资源开展自主学习的能力有待提高,学生主体性和个性化学习需求尚未满足,英语听说教学的线上资源利用有待进一步提升,线上资源整合与教学应用的范围有待延伸和拓展,线上资源的教学管理水平有待加强,英语教师组织开展线上教学能力有待提升等问题。大学英语线上资源的整合利用与教学实践应该提升学生利用线上资源开展自主学习的意识和能力,发挥学习者主体性,重点加大英语听说线上资源的整合利用力度,拓展英语线上资源建设,加强对线上资源的监督与管理,积极提升大学英语教师信息化素养。

关键词：大学英语线上资源资源整合教学实践学生自主学习教师信息化素养

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网络环境下大学英语自主学习模式探析

教育理论与实践 2016年第33期36卷 52-53页

作者：滑少枫河套学院外国语言文学系

当今时代,网络信息技术正发生着日新月异的变化。如何让学生有效地利用网络,提高大学英语学习水平,达到有效的自主学习目标,已经成为大学英语课堂教学的热点。当前,大学英语自主学习存在学习目标模糊、学习动机不强、自主学习策略不够... 详细信息

当今时代,网络信息技术正发生着日新月异的变化。如何让学生有效地利用网络,提高大学英语学习水平,达到有效的自主学习目标,已经成为大学英语课堂教学的热点。当前,大学英语自主学习存在学习目标模糊、学习动机不强、自主学习策略不够有效、自我监控评价不够科学等问题。提高大学英语自主学习的有效性,应培养学生的学习兴趣,完善学习评价与监督机制,引导教师转变自身角色。

关键词：网络环境大学英语自主学习

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后张预应力加固砖砌体墙体抗震性能试验研究

工程抗震与加固改造 2013年第5期35卷 71-78页

作者：刘航华少锋北京市建筑工程研究院有限责任公司北京100039 北京建筑工程学院北京100044

提出了采用后张预应力对砖砌体结构进行抗震加固的新技术,为验证加固效果,进行了8片采用后张预应力技术加固的砖砌体墙体在水平低周反复荷载下的试验研究.对比分析了未加固墙体与加固墙体的破坏形态和受力特点.试验结果表明,后张预应力... 详细信息

提出了采用后张预应力对砖砌体结构进行抗震加固的新技术,为验证加固效果,进行了8片采用后张预应力技术加固的砖砌体墙体在水平低周反复荷载下的试验研究.对比分析了未加固墙体与加固墙体的破坏形态和受力特点.试验结果表明,后张预应力加固砖砌体墙体可以显著提高墙体的抗震性能,加固后墙体的抗剪承载力提高幅度介于1.28～2.11倍之间,延性系数提高幅度介于1.33 ～3.8倍之间,墙体的破坏形态也明显改善.在试验研究的基础上,提出了后张预应力加固砖砌体墙体的施工工艺.

关键词：砖砌体墙后张预应力加固低周反复荷载试验施工工艺

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黑果菝葜中2个新化学成分（英文）

中国中药杂志 2018年第5期43卷 959-963页

作者：舒积成刘敏朱根华刘荣华邵峰黄慧莲江西中医药大学

从黑果菝葜中分离得到1个新的倍半萜（黑果菝葜萜醇A，1）和1个新的苯丙素苷化合物（黑果菝葜苷A，2），以及6个已知化合物，trichothecolone（3），β-D-（6．0-trans-feruloyl）fructofuranosyl-α-D-0-glucopyranoisde（4），3，4，5-三甲氧基-苯酚葡萄糖苷（5），（4R）-p-薄荷-1-烯-7，8-二醇-7-O-β-D-吡喃葡萄糖苷（6），柚皮素（7），大黄素-8-O-β-葡萄糖苷（8），根据NMR，MS等波谱方法和理化性质，并结合文献，鉴定了其化学结构。化合物3．8均为首次从此植物中分离得到。

关键词：黑果菝葜倍半萜苯丙素苷黑果菝葜萜醇A 黑果菝葜苷A

跨文化交际理论下的旅游文本英译——以阴山岩画景点为例

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教育教学论坛 2018年第9期 88-89页

作者：滑少枫河套学院内蒙古巴彦淖尔015000

语言作为文化的载体,任何语言的表述都反映着某种文化,同样的道理,文化的进步也影响着人们使用语言的方式。由此可见,语言与文化之间有着十分紧密的联系。尤其是近几年,随着我国旅游业的迅速发展,跨文化交际理论下所形成的旅游文本英译... 详细信息

语言作为文化的载体,任何语言的表述都反映着某种文化,同样的道理,文化的进步也影响着人们使用语言的方式。由此可见,语言与文化之间有着十分紧密的联系。尤其是近几年,随着我国旅游业的迅速发展,跨文化交际理论下所形成的旅游文本英译开始成为外国人士了解中国文化的有效途径,而这也就决定了旅游文本英译存在的重要性。鉴于此,本文主要以阴山岩画景点为例,就"跨文化交际理论下的旅游文本英译"这一主题展开分析。

关键词：跨文化交际理论旅游文本英译阴山岩画