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1.
二氯二茂钛的合成及其对SBS加氢催化性能的研究   总被引:1,自引:0,他引:1  
以二聚环戊二烯(dicyclopentadiene)为原料,将其裂解得到环戊二烯(cyclopentadiene,Cp);在二乙胺存在的条件下将其与四氯化钛反应,合成了二氯二茂钛(titanocene dichloride,TDC),并以合成的目标产物作为丁苯嵌段共聚物(SBS)加氢催化剂,对其催化性能进行了研究。当加氢反应温度为70℃,压力为2.0MPa,催化剂用量为0.4mmol/100g聚合物时,SBS中加氢度达到94.2%。说明目标产物具有良好的催化性能。  相似文献   
2.
A new type of thermal stabilizer, antimony pent (isooctyl thioglycollate) (Sb(SCH2 COOC8 H17 )5), was synthesized by using antimony trioxide, isooctanol and thioglycolic acid in 2 steps. Firstly, antimony trioxide was oxidized into colloidal antimony peroxide. Then antimony peroxide and isooctyl thioglycollate reacted stoichiometrically for 2 h with the yield of 87%. This compound was used as thermal stabilizer for polyvinyl chloride(PVC).The results show that the thermal stability time is 52 rain at 200℃ by heat-ageing oven test when adding 2. 5% thermal stabilizer to PVC resin. Compared with antimony tris(isooctyl thiolycollate), the initial thermal stability of antimony pent(isooctyl thioglycollate) is better than that of antimony tris(isooctyl thioglycollate), while the longterm thermal stability time is shorter than that of antimony tris(isooctyl thioglycollate). Meanwhile, the synergism of antimony pent(isooctyl thioglycollate) with calcium stearate was studied, indicating that when the mass ratio of antimony pent(isooctyl thioglycollate) to calcium stearate is 2:1, the thermal stability time of PVC is 58 min.  相似文献   
3.
铕三元配合物的合成、表征及其光致发光性能   总被引:1,自引:0,他引:1  
以苯甲酸、邻苯二甲酸、间苯二甲酸、水杨酸、丙烯酸、甲基丙烯酸、α—噻吩基三氟甲酰丙酮为第一配体,二安替比林甲烷,三正辛基氧化膦、2,2’-联吡啶、邻菲咯啉及邻菲咯啉N-氧化物为第二配体,合成了系列铕三元配合物。经元素分析确定了它们的组成;研究了它们的紫外吸收光谱、红外吸收光谱及荧光光谱。紫外光谱的研究表明,配合物的紫外吸收主要表现为配体的吸收,但是吸收峰的位置发生了移动;红外光谱的研究表明,配合物的红外光谱不同于自由配体的红外光谱,在400~500 cm-1出现了吸收峰,这是Eu-O的伸缩振动峰;荧光光谱的研究表明,第二配体的加入可以显著提高配合物的荧光性能。  相似文献   
4.
Light conversion agents Eu1-x Lx (TTA)3 Phen (L denotes La3+ , Gd3+ , Y3+ ) complexes were prepared,and the influence of doping ions on fluorescence properties was investigated by elementary analysis, FTIR and fluorescent spectra. The results show that FTIR spectra of Eu1_x Lx (TTA)3 Phen complex system are identical with that of EuTTA3 Phen, which indicates that the complexes Eu1 xLx(TTA)3Phen are similar in structure to Eu (TTA)3Phen. For the above doping elements, co-fluorescence enhancement has the following order: Gd3+ >Y3+ >La3+ , and the optimum mole fractions of doping elements are 0.4, 0.2 and 0.5 respectively for Gd3+ , Y3+ ,La3+. Among all the complexes, Eu0.6 Gd0.4 (TTA)3 Phen complex has the strongest fluorescent intensity. Applying Eu0.6 Gd0.4 (TTA)3 Phen complex to plastic and printing inks, bright red fluorescence plastic and printing inks are obtained when the content of europium reaches 0.1% (mass fraction).  相似文献   
5.
过渡金属硫化物作为高效的非贵金属催化剂,已在化工领域得到了广泛的应用.但是,很少将其应用于硝基化合物的催化加氢反应中.在本文中,通过硫化金属有机框架材料ZIF-67,并在氨气气氛下进行退火,制备得到了CoSx/NC催化剂.研究发现,该类催化剂的结构和组成可通过改变退火温度进行调控.特别是,当退火温度为500℃时,得到的...  相似文献   
6.
在有机溶剂中利用固定化脂肪酶Novozym 435催化酯化反应以分离扁桃酸对映体,考察了反应时间、温度、摇床转速、加酶量、扁桃酸浓度及乙醇浓度对反应转化率和产物对映体过量值(eep)的影响.结果表明,在二氯乙烷中,拆分扁桃酸对映体的最佳条件为:加酶量40 mg,扁桃酸20 mM,乙醇80 mM,转速150 rpm,温度40°C.在此条件下,反应24h后,转化率为30%,产物中R-扁桃酸乙酯eep达到92%.  相似文献   
7.
The thermal decomposition reaction of Eu2(p-MBA)6(PHEN)2 (p-MBA=CH3C6H4COO, methylbenzoate;PHEN=C12H8N2, 1,10-phenanthroline) was studied in a static atmosphere usingTG-DTG method. The thermal decom position process of the complex was determined and its kinetics was investigated. Kinetic parameters were obtained from the analysis of TG-DTG curves by means of the Achar method and the Madhusudanan-Krishnan-Ninan (MKN) method.The most probable mechanism functions of the thermal decomposition reaction for the first stage are: f(α)= (1-α)2,g(α) = (1 -α) 1- 1. The activation energy for the first stage is 255.18 k J/mol, the entropy of activation AS is 227.32 J/mol and the Gibbs free energy of activation AG is 128.04 k J/mol.  相似文献   
8.
The binary complexes of terbium with benzoic acid and its derivatives (phthalic acid, iso-phthalic acid, oaminobenzoic acid, salicylic acid, sulfosalicylic acid) were synthesized and their compositions were identified by elemental analyses. UV, IR of the complexes were investigated. The UV spectra indicate that the complexes‘ ultraviolet absorption is mainly the ligands‘ absorption, but the location of peak drifts. The IR spectra show that the IR spectra of complexes are different from those of free ligands, and the band at 400 - 500 cm^-1 , due to the stretching vibration of Tb--O, is absent for free ligands. The fluorescence properties were investigated by using luminescence spectroscope, the results show that all the six complexes of terbium exhibit excellent luminescence, due to the transition from the lowest excited state ^5D4 to ^7F ground state manifold, the complexes of terbium with sulfosalicylic acid have the strongest fluorescence intensity, and is stronger than o-aminobenzoic acid-terbium, whose fluorescence intensity is regarded as the strongest one in the literature, and even stronger than some phosphor of terbium.  相似文献   
9.
通过共沉淀法制备ZnO/ZnAl2O4纳米异质结光催化剂,利用HRTEM、TEM、XRD、BET、TG-DTA和UV-Vis DRS 测试方法对样品进行表征。在模拟太阳光照射下,通过测定甲基橙溶液的光催化降解率和对大肠杆菌的杀灭率来评价样品的光催化活性。研究催化剂的组成、焙烧温度、催化剂的用量和不同光源对样品光催化活性的影响。结果表明,当原料中Zn与Al摩尔比为1:1.5时,在600℃焙烧所得的催化剂具有最佳光催化活性。在模拟太阳光照射下,在50 min内1.0 g/L光催化剂对甲基橙的降解率达98.5%;在60 min内,在相同条件下对大肠杆菌(106 CFU/mL)的杀菌率达到99.8%。  相似文献   
10.
支撑液膜法提取稀土的动力学   总被引:1,自引:0,他引:1  
研究了以聚丙稀为支撑膜,以二(2-乙基已基)磷酸为载体提取稀土的支撑液膜体系。通过实验确定为料液的pH值,载体浓度等与稀土离子渗透系数之间的关系;建立了动力学方程;并计算了料液-膜侧传质边界层的厚度和稀土配合物在膜内的扩散系数。  相似文献   
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