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磷酸酯钕催化体系对异戊二烯聚合的影响
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作者 侯红霞 陈晓丽 +2 位作者 苏忠魁 焦俊卿 张学全 《合成橡胶工业》 CAS CSCD 北大核心 2015年第6期433-437,共5页
以Nd(P204)3(简称Nd)/Al(i-Bu)2H(简称Al)/Al(i-Bu)2Cl(简称Cl)为催化剂,对异戊二烯(Ip)进行聚合,考察了Ip聚合的影响因素,并通过傅里叶变换红外光谱表征了聚合物的微观结构。结果表明,随着Al/Nd(摩尔比)的增大,聚合收率增大,聚合物的... 以Nd(P204)3(简称Nd)/Al(i-Bu)2H(简称Al)/Al(i-Bu)2Cl(简称Cl)为催化剂,对异戊二烯(Ip)进行聚合,考察了Ip聚合的影响因素,并通过傅里叶变换红外光谱表征了聚合物的微观结构。结果表明,随着Al/Nd(摩尔比)的增大,聚合收率增大,聚合物的数均分子量减小,分子量分布变宽,顺式-1,4-结构摩尔分数下降,但均在98%以上;随着Cl/Nd(摩尔比)的增大,聚合收率先增大后减小,聚合物的重均分子量(珚Mw)减小,分子量分布变宽,顺式-1,4-结构摩尔分数略有下降,但均超过96%;随着三元陈化时间的延长,聚合收率减小,聚合物的珚Mw增大,分子量分布变窄,顺式结构无明显变化;随着聚合温度的升高,聚合收率先增大后减小,聚合物的珚Mw减小,分子量分布变宽,顺式-1,4-结构含量下降;在Al/Nd为5,Cl/Nd为2.5,三元陈化时间为60 min,聚合温度为30℃的最佳反应条件下所得聚合物的顺式-1,4-结构摩尔分数达到98.74%。 展开更多
关键词 磷酸酯钕 二异丁基氢化铝 二异丁基氯化铝 异戊二烯 高顺式 分子量分布
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二异丁基氢化铝Ⅰ(DIBAL-H Ⅰ)还原碘代苯甲醛的研究 被引量:1
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作者 王光胤 王锐 《化学工程师》 CAS 2021年第3期1-3,共3页
利用二异丁基氢化铝Ⅰ(DIBAL-H Ⅰ)在反应进行时可以不破坏苯环上其他官能团的特性,由碘代苯甲醛与无水二氯甲烷外加溶解在甲苯中的二异丁基氢化铝溶液中的碘代苯甲醇(首先经过搅拌,然后向混合物中加入饱和的酒石酸钠水溶液,接下来通过... 利用二异丁基氢化铝Ⅰ(DIBAL-H Ⅰ)在反应进行时可以不破坏苯环上其他官能团的特性,由碘代苯甲醛与无水二氯甲烷外加溶解在甲苯中的二异丁基氢化铝溶液中的碘代苯甲醇(首先经过搅拌,然后向混合物中加入饱和的酒石酸钠水溶液,接下来通过萃取、洗涤、干燥等过程合成),然后对产物进行了核磁共振氢谱图、核磁共振碳谱图以及高分辨质谱(HR-MS)的分析。并与常用还原剂硼氢化钠做对比,在制备目标产物碘代苯甲醇时进行了平行实验,分别对反应温度,反应时间,反应溶剂进行筛选,结果证明,0℃为反应的最优温度。二氯甲烷为最优溶剂,2h为最佳反应时间的最优反应条件。 展开更多
关键词 二异丁基氢化铝Ⅰ(DIBAL-HⅠ) 反应温度 搅拌时间
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Effect of Low-Pressure Nitrogen DC Plasma Treatment on the Surface Properties of Biaxially Oriented Polypropylene, Poly (Methyl Methacrylate) and Polyvinyl Chloride Films 被引量:2
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作者 S. Hamideh MORTAZAVI Mahmood GHORANNEVISS +4 位作者 Soheil PILEHVAR Sina ESMAEILI Shamim ZARGHAM S. Ebrahim HASHEMI Hamzeh JODAT 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第4期362-367,共6页
In this study, commercial biaxially oriented polypropylene (BOPP), polyvinyl chlo- ride (PVC) and poly (methyl methacrylate) (PMMA) films were treated with nitrogen plasma over different exposure times in a Py... In this study, commercial biaxially oriented polypropylene (BOPP), polyvinyl chlo- ride (PVC) and poly (methyl methacrylate) (PMMA) films were treated with nitrogen plasma over different exposure times in a Pyrex tube surrounded by a DC variable magnetic field. The chemi- cal changes that appeared on the surface of the samples were investigated using Fourier transform infrared (FT4R) spectroscopy and attenuated total reflectance Fourier transform infrared (ATR- FTIR) spectroscopy after treatment for 2 min, 4 min and 6 rain in a nitrogen plasma chamber. Effects of the plasma treatment on the surface topographies and contact angles of the untreated and plasma treated films were also analyzed by atomic force microscopy (AFM) and a contact angle measuring system. The results show that the plasma treated films become more hydrophilic with an enhanced wettability due to the formation of some new polar groups on the surface of the treated films. Moreover, at higher exposure times, the total surface energy in all treated films increased while a reduction in contact angle occurred. The behavior of surface roughness in each sample was completely different at higher exposure times. 展开更多
关键词 plasma surface treatment biaxially oriented polypropylene polyvinyl chlo-ride poly (methyl methacrylate) wettability
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CATHODIC REDUCTION OF METAL-CHLORIDE COORDINATION IONS 被引量:1
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作者 Zen, Zhenou(Department of Applied Chemistry Chemistry,South China University of Technology, Guangzhou510641, China)Yang, Songqing(Department of Chemistry, Central South University of Technology, Changsha 410083, China) 《中国有色金属学会会刊:英文版》 CSCD 1994年第1期39-44,共6页
CATHODICREDUCTIONOFMETAL-CHLORIDECOORDINATIONIONSZen,Zhenou(DepartmentofAppliedChemistryChemistry,SouthChina... CATHODICREDUCTIONOFMETAL-CHLORIDECOORDINATIONIONSZen,Zhenou(DepartmentofAppliedChemistryChemistry,SouthChinaUniversityofTechn... 展开更多
关键词 cathodic reduction METAL CHLORIDE COORDINATION IONS copper CHLORIDE ZINC chlo-ride lead CHLORIDE chronopotential method
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Gastro protective properties of the novel prostone SPI-8811 against acid-injured porcine mucosa
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作者 Meghali Nighot Adam Moeser +1 位作者 Ryuji Ueno Anthony Blikslager 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第34期4684-4692,共9页
AIM:To evaluate the protective properties of novel prostone ClC-2 agonist SPI-8811 in porcine model of gastric acid injury. METHODS:Porcine gastric mucosa was mounted in Ussing chambers and injured by bathing mucosal ... AIM:To evaluate the protective properties of novel prostone ClC-2 agonist SPI-8811 in porcine model of gastric acid injury. METHODS:Porcine gastric mucosa was mounted in Ussing chambers and injured by bathing mucosal tissues in an HCl Ringer's solution (pH = 1.5) with or without SP1-8811 (1 μmol/L), cystic fibrosis transmem-brane conductance regulator (CFTR) inhibitor (inhibitor 172, 10 μmol/L, apical) and ClC-2 inhibitor ZnCl 2 , 300 μmol/L, apical), on the apical surface of tissues. Transepithelial resistance and mucosal-to-serosal 3 H-mannitol fluxes were measured over a 90-min period. Tissues were analyzed by morph metric techniques, Immunofluorescence and by western blots. RESULTS:Compared with control tissues, acid exposure decreased transepithelial electrical resistance (TER) and increased 3 H-mannitol flux. Pretreatment of gastric mucosa with SPI-8811 was protective against acid-induced decreases in TER (TER, 50 Ω . cm 2 vs 100 Ω . cm 2 ) and abolished increases in flux ( 3 H-mannitol flux, 0.10 μmol/L . cm 2 vs 0.04 μmol/L . cm 2 ). Evidence of histological damage in the presence of acid was markedly at- tenuated by SPI-0811. Immunofluorescence and western analysis for occludin revealed enhanced localization to the region of the tight junction (TJ) after treatment with SPI-8811. Pretreatment with the ClC-2 inhibitor ZnCl 2 , but not the selective CFTR inhibitor 172, attenuated SPI-8811-mediated mucosal protection, suggesting a role for ClC-2. Prostone may serve both protective and reparative roles in injured tissues. CONCLUSION: ClC-2 agonist SPI-8811 stimulated enhancement of mucosal barrier function by protecting TJ protein occludin in porcine gastric mucosa and thus protected the gastric acid injury in porcine stomach. 展开更多
关键词 STOMACH Mucosal permeability CIC-2 chlo-ride channel Tight junction
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Observation of changes in the number of myocardial capillaries in rabbits after treatment of acute myocardial infarction by Tongxinluo superfine powder 被引量:1
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作者 Wu Haotian Zhang Fengshun +3 位作者 Liu Jinyi Li Xuezhao Guo Fei Wu Yiling 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2018年第3期406-411,共6页
OBJECTIVE: To investigate the effects of Tongxinluo superfine powder on cardiac function, infarct size and the number of myocardial capillaries in a rabbit model of acute myocardial infarction.METHODS: A total of 32 N... OBJECTIVE: To investigate the effects of Tongxinluo superfine powder on cardiac function, infarct size and the number of myocardial capillaries in a rabbit model of acute myocardial infarction.METHODS: A total of 32 New Zealand white rabbits were randomly divided into four groups: sham operation group, model group, treatment group,and pre-treatment, the experiment of pre-treatment group was performed 6 weeks early than the treat) group,The four groups use a unified modeling technique. An acute myocardial infarction model was established through external application of70% ferric chloride on the coronary artery. After 7 d,electrocardiogram, ultrasonography of cardiac function, micro-computed tomography, pathology and other data were collected.RESULTS: In the treatment and pre-treatment groups, ejection fraction, left ventricular short axis shortening rate, left ventricular end-systolic diameter and cardiac output significantly improved, the number of capillaries significantly increased, and infarct size significantly decreased. In addition, the results suggest that the value of intra-ventricular pressure and the situation of electrocardiogram also changed to different degrees with the increasing of treatment of cycle.CONCLUSION: Tongxinluo superfine powder can protect the myocardium, improve the blood supply of the myocardium and reduce the degree of myocardial injury, during acute stage of myocardial infarction. 展开更多
关键词 MYOCARDIAL INFARCTION MYOCARDIUM Mi-crocirculation X-Ray Microtomography Ferric chlo-ride TONGXINLUO superfine powder
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