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1.
Kaminsky型催化剂化乙烯齐聚:二酚基二茂锆的催化作用   总被引:6,自引:0,他引:6  
王梅  沈玉梅 《分子催化》1999,13(4):282-286
通过改变Al/Zr比,反应温度及反应时间,分别考察了Cp2Zr(OAr)2/EAO(Ar=C6H5、p-C6H4Me、M-c6h4no2、P-c6h4no2)4种体系对乙烯齐聚的催化作用,发现用Cp2Zr(OAr)2代替Cp2ZrCl2作为主催化剂,对于Kaminsky型体系Cp2ZrL2/EAO催化乙烯齐聚,具有调变作用,在提高催化活性的同时,可使低碳烯烃的造反  相似文献   

2.
在亚乙基双( 茚基) 二胺化茂铪(rac C2H4(Ind)2Hf(NMe2)2 ,简称1 ,Ind = 茚基,Me= 甲基) 催化作用下,对乙烯(E) 与1 辛烯(O) 无规共聚合进行了研究.作为比较,利用异亚丙基( 环戊二烯基)(1 芴基) 二甲基锆茂催化体系((CH3)2C(Fluo)(Cp)ZrMe2 ,简称2 ,Fluo = 芴基,Cp = 环戊二烯基) 对乙烯/1 辛烯在相同共聚合条件下进行了共聚合.结果表明,在单体浓度比[O]/[E] 较小时共聚合速率随单体浓度比增加而增加,进一步增加单体浓度比则导致共聚合速率降低.催化体系1/Al(iBu)2H/[Ph3C][B(C6F5)4](3) 催化共聚活性比2/ MAO高得多.共聚物中辛烯含量随反应单体1 辛烯含量的增加而增加,两单体竞聚率乘积( rE×ro) 小于1 ,表明聚合物为无规共聚物.相同共聚单体浓度比下1/Al(iBu)2H/3 催化共聚物中辛烯含量比2/ MAO 共聚物中辛烯含量高,表明前者具有更强的共聚合能力.所得无规共聚物熔点温度、结晶度、本体粘度及密度随共聚物中辛烯含量的增加而显著降低.辛烯含量较高时共聚物呈现明显无结晶行为.差示扫描量热分析显示,同乙烯均聚?  相似文献   

3.
钱明星  黄勇 《分子催化》2000,14(1):29-32
合成了Ind2Zr(OC6H3-3,5-Me)2(A)、Ind2ZrCl(OCyH3-3,5-Me2)(B)和Ind2ArCl2(C)3个化合物,并在不同反应温度、陈化温度、反应时间等条件下,分别考察了每个化合物与Et2AICl所组成的催化体系对乙烯剂聚活笥和选择性的影响。在相同条件下,催化剂活性顺序为A〉B〉C,在最佳反应条件下,Ind2Zr(OC6H3-3,5Me2)2的催化活必来1951g齐  相似文献   

4.
CpM(CO)3SnPh3和CpM(co)3sNpH2x(Cp=C5H4CH3,C5H4COCH3;M=Mo,W;X=Cl,Br)与HCl或HBr发生取代反应,得到三氯、三溴以及混合三卤代锡钨(钼)双核化合物,并经元素分析、^1H NMR、IR表征。化合物Cl3SnW(CO)3C5H4COCH3的晶体属单斜晶系,空间群为P21/c,a=0.7686(3)nm,b=1.2622(2)nm,c=1.6  相似文献   

5.
二茚基二芳氧基锆催化乙烯齐聚   总被引:1,自引:0,他引:1  
直链低碳α 烯烃是生产线性低密度聚乙烯 (LLDPE)和高密度聚乙烯 (HDPE)的共聚单体 .Kaminsky型催化剂是 80年代发展起来的烯烃高效聚合催化剂[1].近年来亦有文献报道该类催化剂催化乙烯齐聚合成低碳α 烯烃[2~ 5].而以茚基锆化合物与氯化烷基铝所组成的催化体系催化乙烯齐聚还未见文献报道 .本文考查了茚基锆化合物和一氯二乙基铝所组成的二元催化体系对乙烯齐聚的催化性能 ,合成了Ind2 Zr(OC6 H4 p Me) 2 、Ind2 Zr(OC6 H5) 2 、Ind2 ZrCl2 和Cp2 Zr(OC6 H4 p Me) 2 4个化合物 ,…  相似文献   

6.
标题化合物是反应体系(NH4)3VS4/CoC2(PPh3)2/NEt4Cl在CH2CI2中反应而得到的,单晶X射线结构分析表明其晶体地立方晶系,化学式为C26H35NCl3CoP,空间群为Pa3,Mr=557.84,a=17.807(5),A,V=5646.4A^3,Z=8,Dc=1.31g/cm^3,F(000)=2328,μ(MoKa)=9.6cm^-1,R=0.062,Rw=0.067,标  相似文献   

7.
通过N-取代三氯乙酰胺与不同的脂肪二胺反应,合成了5种新的N,N”-多亚甲基双(N’-(4-氯苯基)脲(ArNHCONH(CH2)nNHCONHAr,n=2~6,Ar=4-ClC6H4)其结构经元素分析,HNMR和IR证实。  相似文献   

8.
合成了两种稀土高氯酸盐与L-脯氨酸配合物的晶体.经热重、差热、化学分析及对比有关文献,知其组成 是[Pr2(L-Pro)6(H2O)4](ClO4)6和[Er2(L-PrO)6(H2O)4](ClO4)6,质量分数为99.24%和98.20%.选用RE(NO3)· 6H2O(RE=Pr,Er)、LPro、NaClO4·H2O和 NaNO3作辅助物,使用具有恒温环境的反应热量计,以 2 mol·L-1HCl 作溶剂,分别测定了[2RE(NO3)3·6H2O+6L-PrO+6NaClO4·H2O]和{ [RE2(L-PrO)6(H2O)4](ClO4)6+6NaNO3}在 298.15 K时的溶解热.设计一热化学循环求得化学反应的反应焓rH分别是:63.904 kJ·mol-1和 91.017 kJ·mol-1,经计算得配合物[RE2(L-Pro)6(H2O)4](ClO4)6(s)在 298.15 K时的标准生成焓(298.15 K)分别 是-6 594.78 kJ·mol-1和-6 532.87 kJ·mol-1。  相似文献   

9.
测定了三元体系Zn(ClO4)2-L-H2O(L=DAPTU,N,N'-二安替比林硫脲,L=MAPTU,N-甲基N'-安替比林硫脲)在30℃时的溶解度和饱和溶液的折学率,绘制了相应的溶度图和折光率、组成图。体系的浓度曲线和折光率曲线均由3支组成,民L(L=DAPTU,MAPTU)、Zn(ClO4)2.L2.nH2O(L=DAPTU,n=2;L=MAPTU,n=0)和Zn(ClO4)2.6H2O相应  相似文献   

10.
SYNTHESIS AND CHARACTERIZATION OF HETEROBIMETALLIC COMPLEXES:(Cp_2LnOCH_2C_6H_5)Cr(CO)_3(Ln=Gd,Dy,Yb,Y)¥ChangTaoQiAN;JianHuaGUO?..  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

14.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

15.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

16.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.  相似文献   

18.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

19.
潘素娟  全灿  周俊波 《化学通报》2014,77(12):1165-1170
测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。  相似文献   

20.
微量钙的测定方法研究进展   总被引:5,自引:0,他引:5  
介绍了1995-2006年期间测定微量和痕量钙的方法,如电感耦合等离子体-原子发射光谱法、原子吸收光谱法以及离子色谱法等的工作原理和特点,并说明了其测定微量钙的应用领域。并对微量钙的测定技术进行了展望(引用文献55篇)。  相似文献   

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