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Effect of crystallization temperature and propylene sequence length on the crystalline structure of propylene-ethylene random copolymers

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Chinese Science Bulletin 2008年第12期53卷 1804-1812页

作者： GOU QingQiang LI HuiHui YU zhenqiang chen ErQiang ZHANG YuDong YAN ShouKe Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Department of Polymer Science School of Chemistry Peking University Beijing 100871 China Beijing Research Institute of Chemical Industry SINOPEC Beijing 100013 China candidate of Graduate University of Chinese Academy of Sciences Beijing100039 China

Crystallization behavior and resultant crystalline structure of a series of temperature-rising elu-tion-fractionated specimen of a Ziegler-Natta catalyst-synthesized propylene-ethylene random co-polymer were studied by DSC, WAXD and AFM. The experimental results indicate that both crystalliza-tion temperature and propylene sequence length exhibit great influence on the crystallization behavior and crystalline structure of the copolymer. It was found that the ethylene co-monomers acting as point defects inserted into the polypropylene chains play an important role in the formation of γ-iPP. As the co-monomer content increases, the crystallizable sequence length of iPP decreases, which produces an appropriate condition for its γ crystallization. At the same time, the existence of chain defects leads to a lower crystallinity of the copolymer and imperfection of the resultant crystals. For each individual sample with certain propylene sequence length or ethylene content, the increment of γ-iPP crystal content with increasing crystallization temperature demonstrates that higher crystallization tempera-ture is in favor of the γ-iPP crystallization. Pure γ-iPP crystals have been got in samples with propylene sequence length lower than 21 under suitable crystallization conditions.

关键词：结晶温度晶体乙烯共聚物

1-((12-Bromododecyl)oxy)-4-((4-(4-pentylcyclohexyl)phenyl)ethynyl) benzene: Liquid crystal with aggregation-induced emission characteristics

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Science China Chemistry 2013年第9期56卷 1191-1196页

作者： chen YaFei LIN JieSheng YUAN WangZhang YU zhenqiang LAM Jacky WingYip TANG Ben Zhong Shenzhen Key Laboratory of Functional Polymers School of Chemistry and Chemical EngineeringShenzhen University National Institutes for Food and Drug Control School of Chemistry and Chemical engineering Shanghai Jiao Tong University Department of Chemistry The Hong Kong University of Science & Technology

The luminescent liquid crystals (LLCs) are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for LCs. Herein, we developed a new strategy of applying aggregation-induced emission (AIE) phenomenon to the molecular design of LCs towards LLCs. In this report, a calamitic liquid crystal based on tolane with AIE characteristics was successfully synthesized and the chemical structure was characterized by 1H, 13C NMR, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) high-resolution mass spectra. The fluorescence behavior was studied by fluorescence spectroscopy and the liquid crystal phase behaviors were investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM). The crystal structure was obtained by X-ray diffraction crystallography with P1 space group. Results demonstrated that the sample was AIE active and the LC phases sequence during cooling was nematic, smectic C and smectic B phase.

关键词： aggregation-induced emission tolane liquid crystal phase behavior

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心脏病患者体外循环术后辨证施治的临床观察

世界中医药 2008年第6期3卷 329-331页

作者：叶生爱陈振强张辉赵扬施义程亮张颖单兆伟江苏省中医院心胸外科南京市汉中路155号210029

目的:对心脏病患者体外循环术后的中医证型规律及辨证施治进行初步探讨。方法:将冠心病及瓣膜病心脏体外循环术后患者分为治疗组38例和对照组42例,治疗组于术后10天内进行中医辨证分型及治疗,比较2组患者临床症状、舌脉改善时间及血液... 详细信息

目的:对心脏病患者体外循环术后的中医证型规律及辨证施治进行初步探讨。方法:将冠心病及瓣膜病心脏体外循环术后患者分为治疗组38例和对照组42例,治疗组于术后10天内进行中医辨证分型及治疗,比较2组患者临床症状、舌脉改善时间及血液流变学变化。结果:治疗组总有效率为92.11%,其临床症状、舌脉改善时间均优于对照组,P<0.01;2组在血液流变学上无明显变化。结论:中医辨证施治可促进心脏病患者体外循环术后的康复,改善消化道症状,提高患者生活质量。

关键词：体外循环术后中医药疗法临床分析治疗方法

急性前循环动脉粥样硬化性串联闭塞患者球囊扩张与支架置入的效果

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介入放射学杂志 2024年第6期33卷 593-598页

作者：李威冯晓丽王康萌黄开来孙刚陈蓉赵振强关海涛海南医学院第一附属医院神经内科海南海口570105 广州医科大学附属第三医院神经内科

目的比较颈内动脉起始段粥样硬化性串联闭塞患者颈内动脉颅外段行球囊扩张或支架置入的安全性和有效性。方法纳入2018年1月至2022年10月海南医学院第一附属医院和广州医科大学附属第三医院收治的发病24 h内行血管内治疗的急性前循环串... 详细信息

目的比较颈内动脉起始段粥样硬化性串联闭塞患者颈内动脉颅外段行球囊扩张或支架置入的安全性和有效性。方法纳入2018年1月至2022年10月海南医学院第一附属医院和广州医科大学附属第三医院收治的发病24 h内行血管内治疗的急性前循环串联闭塞脑卒中患者91例,分为球囊扩张组51例,支架置入组40例,比较两组基线和临床资料。mTICI 2b~3定义为血管良好再通,术后90 d改良Rankin量表(mRS)评分0~2分定义为临床预后良好。结果支架组患者术后血管良好再通率和90 d良好临床预后率较球囊组高,分别为70%比60.8%和60%比52%,但差异无统计学意义(P=0.361、0.391)。两组症状性颅内出血发生率、无症状性颅内出血发生率和病死率分别为10%比11.8%、32.5%比41.2%、22.5%比17.7%,差异均无统计学意义(P=1.000、0.396、0.564)。结论颈内动脉起始段动脉粥样硬化性病变所致的急性前循环串联闭塞患者,急性期颅外段行球囊扩张或支架置入可能均安全有效。

关键词：急性前循环串联闭塞动脉粥样硬化性病变球囊扩张支架置入血管内治疗

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创伤性湿肺的平片与螺旋CT诊断

临床医学 2006年第5期26卷 18-19,F0004页

作者：黄楚绵黄映宏唐大治李仰康陈振强刘国瑞汕头大学医学院第二附属医院放射科广东汕头515041

目的总结X线平片、螺旋CT胸部检查对创伤性湿肺的诊断价值。方法回顾性分析经临床证实的创伤性湿肺患者52例,全部病例行胸部X线平片与CT检查。结果创伤性湿肺多出现在一侧和/或两侧中下肺野,表现为:①间质型(9例):肺血管影增粗、模糊;... 详细信息

目的总结X线平片、螺旋CT胸部检查对创伤性湿肺的诊断价值。方法回顾性分析经临床证实的创伤性湿肺患者52例,全部病例行胸部X线平片与CT检查。结果创伤性湿肺多出现在一侧和/或两侧中下肺野,表现为:①间质型(9例):肺血管影增粗、模糊;②弥漫实变型(18例):肺实质内散在斑点状、小片状稍高密度灶;③云雾型(17例):呈磨砂玻璃样改变的云雾状稍高密度灶(即“面纱征”);④节段实变型(8例):大片状或呈叶、段分布的高密度灶;对病变的显示CT明显优于X线平片。结论胸部X平片与CT检查是目前诊断创伤性湿肺有效的检查手段,对临床疑为创伤性湿肺的患者首次建议行胸部X平片与CT检查,对确诊的患者行胸部X线监测。

关键词：肺创伤性湿肺 X线平片 CT

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含砷难处理金矿研究进展

科技资讯 2014年第20期12卷 85-85页

作者：初明陈振强山东地矿国际投资有限公司山东济南250000 锡林浩特鲁地矿业有限公司内蒙古锡林浩特026000

近年来,含砷难处理金矿资源的开发利用已经引起世界各国的广泛关注和重视。其对于提高金的回收率,减少成本,达到环保要求和设计最佳流程等具有重要意义。概括介绍了焙烧氧化、微生物氧化、加压氧化等方面的发展。

关键词：含砷难处理金矿焙烧微生物氧化加压氧化

电视透视下空气灌肠整复法治疗婴幼儿急性肠套叠(附75例分析)

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汕头大学医学院学报 2001年第4期14卷 253-254页

作者：郑浈浈邱礼德陈振强刘国瑞汕头大学医学院第二附属医院放射科广东汕头515041

目的 :探讨电视透视下空气灌肠整复法对婴幼儿急性肠套叠的诊断和治疗价值。方法 :利用可控制压力的结肠注气机 ,在电视监视下对 75例患儿进行诊断性空气灌肠和复位治疗。气压选择 8～ 14 6kPa。结果 :整复成功 6 8例 ,成功率91%。整... 详细信息

目的 :探讨电视透视下空气灌肠整复法对婴幼儿急性肠套叠的诊断和治疗价值。方法 :利用可控制压力的结肠注气机 ,在电视监视下对 75例患儿进行诊断性空气灌肠和复位治疗。气压选择 8～ 14 6kPa。结果 :整复成功 6 8例 ,成功率91%。整复失败 7例 ,其中 1例发生肠穿孔。整复失败病例均采取手术治疗。结论 :选择适当的空气压力 ,配合适当的手法按摩。

关键词：肠套叠空气灌肠婴幼儿电视透视

IVP检查过程应用数字化体层摄影的诊断价值

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实用医学影像杂志 2005年第3期6卷 155-157页

作者：黄楚绵陈振强肖榜喜黄映宏刘国瑞李仰康汕头大学医学院第二附属医院放射科广东汕头515041

目的阐述静脉性肾盂造影(IVP)检查过程同时应用数字化体层摄影技术的临床诊断价值。方法收集63例做IVP检查同时应用数字化体层摄影技术病例的X线诊断资料,与临床和病理结果对照进行回顾性分析。结果整体尿路显影效果:分为有体层组和无... 详细信息

目的阐述静脉性肾盂造影(IVP)检查过程同时应用数字化体层摄影技术的临床诊断价值。方法收集63例做IVP检查同时应用数字化体层摄影技术病例的X线诊断资料,与临床和病理结果对照进行回顾性分析。结果整体尿路显影效果:分为有体层组和无体层组进行统计(每一病例的X线片都包括普通电视下数字摄影和数字化体层摄影,无体层组即体层摄影部分不计),肾影轮廓、肾盂、肾盏、输尿管及膀胱全部清楚显影者,有体层组61例,占96.8%;无体层组59例,占93.7%。本组63例发现病变55例:结石43例合并肾扩张积液18例,占位性病变8例(肾囊肿1例,肾实质癌2例,肾上腺神经节瘤1例,膀胱癌4例),前列腺肥大18例,双肾盂或并双输尿管畸形6例,输尿管下段憩室1例,输尿管囊肿1例,孤立肾1例,慢性肾盂肾炎合并膀胱炎1例。数字化体层摄影对病变的显示更清晰。结论IVP检查过程应用数字化体层摄影对泌尿系疾病有重要的诊断价值。

关键词：静脉性肾盂造影数字化体层摄影诊断价值

Coordination cage with structural “defects” and open metal sites catalyzes selective oxidation of primary alcohols

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Science China Chemistry 2023年第6期66卷 1714-1721页

作者： Tian-Pu Sheng Ying Wei Parvathi Jampani Chang Li Feng-Rong Dai Shuping Huang zhenqiang Wang Zhong-Ning chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry Fuzhou UniversityFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry&Center for Fluorinated Functional Materials University of South DakotaVermillionSDUSA

Coordination cages with intrinsic enzyme-like activity are a class of promising catalysts for improving the efficiency of organic *** present herein a viable strategy to conveniently construct multimetallic active sites into a coordination cage via self-assembly of a pre-formed sulfonylcalix[4]arene-based tetranuclear copper(II)precursor and an amino-functionalized dicarboxylate *** cage exhibits a“defective”,partially open cylindrical structure and features coordinatively labile dimetallic Cu(II)*** by this unique inner cavity environment,promising catalytic activity toward selective oxidation of primary alcohols to carboxylic acids at room temperature is *** studies reveal that the coordinatively labile dimetallic Cu(II)sites can efficiently capture and activate the substrate and oxidant to catalyze the reaction,while the confined nano-cavity environment modulates substrate binding and enhances the catalytic *** study provides a new approach to designing biomimetic multifunctional coordination cages and environmentally friendly supramolecular catalysts.

关键词： coordination cages open metal sites alcohol oxidation host-guest systems supramolecular chemistry