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1.
提高USY型FCC催化剂硫转移和催化裂化活性的研究   总被引:2,自引:0,他引:2  
采用镁、铈、镧和磷对USY型FCC催化剂进行改性,采用FT IR分析方法对改性催化剂的表面酸性进行了表征,研究了硫转移活性组分对催化剂的硫转移和催化裂化活性的影响。结果表明,多次氧化 还原循环后,改性催化剂仍保持较好的硫转移活性,可以达到60%以上。镁的引入会减少基质和分子筛表面强酸的数量,少量镁的引入对催化裂化活性影响不大,铈和镧的引入会使分子筛和基质的表面酸量得到显著增加,提高催化裂化活性,但同时会引起焦炭的增加,磷改性可改善基质和分子筛表面酸性,抑制焦炭的产生,保持催化裂化活性的同时使汽油中的烯烃质量分数下降6%。  相似文献   

2.
邹友思  林国良 《合成化学》1995,3(4):290-291
丙烯腈和丙烯酸酯基团转移共聚的竞聚率邹友思,林国良,戴李宗,兰涛,潘容华(厦门大学化工系,厦门,361005)共聚合中最重要的参数是竞聚率,二元共聚竞聚率对反应机理的研究及生产上的控制均有重要作用。丙烯腈是重要的共聚单体,但它参与的基团转移无规共聚至...  相似文献   

3.
本文报道了5,10,15,20-四(4-乙酰氧基苯)卟吩(T(4AOP)P)及其Cu,Zn,Fe,Co,Ni配合物的合成及其在CH2Cl2-0.1mol/ITBAP体系中的循环伏安(CV)。研究结果。CV实验表明:Cu^2^+,Zn^2^=,Ni^2^+离子以稳定的+2价存在于T(4AOP)P中,电子转移反应在卟啉环上进行,而Fe^3^+,Co^2^+离子在氧化还原过程中发生价态变化。实验发现...  相似文献   

4.
杂多阴离子的相转移化学(Ⅳ)──杂多阴离子与NO的配位反应王恩波,刘霞,王作屏,许林,高丽娟(东北师范大学化学系,长春,130024)关键词杂多阴离子,相转移,NO配位Pope等[1]发现表面含有配位水分子的杂多阴离子可以在相转移作用下转移到非极性溶...  相似文献   

5.
丙烯腈和甲基丙烯酸酯基团转移共聚的竞聚率   总被引:1,自引:1,他引:0  
丙烯腈和甲基丙烯酸酯基团转移共聚的竞聚率邹友思,郭金全,兰涛,戴李宗,潘容华(厦门大学化工系,厦门,361005)关键词基团转移共聚.竞聚率.丙烯腈.甲基丙烯酸酯近年来对基团转移共聚竞聚率的研究较活跃[1~3],一般认为甲基丙烯酸酯和丙烯酸酯两类单体...  相似文献   

6.
聚合物生物碱相转移催化剂的合成及其对多类化学反应的催化性能黄锦霞,陈家威,蒋济隆,卢军(湖北大学化学系,武汉430062)(广西师范大学化学系,南宁530001)关键词相转移催化剂,聚合物,生物碱,三相催化,不对称反应相转移催化反应是有机合成中较为活...  相似文献   

7.
微波作用下乙酰苯胺的N—烷基化反应   总被引:1,自引:0,他引:1  
张晓辉  由业诚 《合成化学》1998,6(2):220-222
探讨了在微波照射下,用相转移催化剂进行了乙酰苯胺的N-烷基化反应,该反应速度快,产率令人满意。  相似文献   

8.
纯Y型硬脂酸铅LB膜的制备及结构表征   总被引:1,自引:0,他引:1  
纯Y型硬脂酸铅LB膜的制备及结构表征陈海燕,彭笑刚,于连香,周勇亮,姜月顺,李铁津(吉林大学化学系,长春,130023)徐跃,高忠民,魏诠(吉林大学测试中心)关键词硬脂酸铅,LB膜转移,硫化铅单层膜在脂肪酸盐LB膜的沉积过程中,存在由Y型向X型沉积的...  相似文献   

9.
甲基丙烯酸酯和丙烯酸酯基团转移共聚的竞聚率   总被引:1,自引:0,他引:1  
甲基丙烯酸酯和丙烯酸酯基团转移共聚的竞聚率邹友思郭金全戴李宗潘容华(厦门大学化工系,厦门,361005)基团转移聚合是制备极性单体的嵌段或无规共聚物的有效方法。如用甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)进行嵌段共聚,可制得热塑性弹性体[1...  相似文献   

10.
描述非绝热电子转移的半经典模型,揭示了对称双势阱非绝热电子转移的过渡态能垒与Arrhenius活化能关系的一些新特征。在4-31G加负离子sp弥散函数水平上优化了共线反应的反应物、络合物和过渡态的构型,成功地进行了电子定域UHF诱导自洽场计算,获得电子转移矩阵元VAB为7.OkJ/mol,活化能垒Ec为28.4kJ/mol,300K时反应速率常数k为9.2×108/s,讨论了理论模型及计算结果。  相似文献   

11.
PVC was used as a model substance to study the dependence of thermal measurement data on the preparation and morphological characteristics of samples The PVC treated was a commercially available suspension polymer, Ongrovil S 155, produced by the Borsodi Vegyi Kombinát. The whole thermal process was followed by TG and DTG measurements in air and argon atmospheres by means of a Du Pont 990 Thermoanalyzer. Evolved-gas analysis was performed with a home-made apparatus. Pyrolysis gas chromatography was accomplished using a Hamilton type pyrolyzer and a Carlo Erba Chromatograph furnished with a flame ionization detector. The investigations showed benzene and other components to be evolved from the initial polymer and an alteration depending on the morphological characteristics of the samples. This was suggested to be due to the different mechanisms of thermal degradation of the PVC.  相似文献   

12.
A rapid, sensitive and selective high performance liquid chromatography (HPLC) method was developed and validated for determination of loganin in rat tissues. Samples were prepared based on a simple protein precipitation. Separation of loganin was achieved on a reversed-phase C(18) column (250 x 4.6 mm, 5 microm) with a mobile phase consisting of acetonitrile and water (16:84, v/v) at a flow rate of 1.0 mL/min. The detection wavelength was set at 236 nm and the temperature of the column was kept at 30 degrees C. The method was applied to study tissue distribution of loganin in rats after a single administration of loganin at a dose of 20 mg/kg. The highest level was observed in kidney, then in stomach, lung and small intestine. The lowest level was found in brain. The peak levels were attained at 90 min in most tissues. It was indicated that kidney was the major distribution tissue of loganin in rats, and that loganin had difficulty in crossing the blood-brain barrier. It was also found there was no long-term accumulation of loganin in rat tissues.  相似文献   

13.
Phthalascidin is a structurally simplified version of Et-743, which is a potent anti-tumor marine natural product isolated from Ecteinascidia turbinata. Its antiproliferative activity is greater than that of the agents taxol, camptothecin, adriamycin, mitomycin C, cisplatin, bleomycin, and etoposide by 1-3 orders of magnitude. An elegant synthesis of Et-743 and phthalascidin has been reported by E. J. Corey and co-workers1,2. As part of our continuing program, we have also engaged in dev…  相似文献   

14.
Immobilization of ultra-thin layer of monoclonal antibody on glass surface   总被引:2,自引:0,他引:2  
When preparing an affinity column and a biosensor, it is desirable to immobilize a unimolecular layer of pure protein on a matrix. In this work, we tried to immobilize a monoclonal antibody on a surface of a glass test-tube as a model, to confirm the stability of this ultra-thin layer by an enzyme immunoassay, and to estimate the thickness of the layer on a slide glass by Fourier transform infrared reflection spectrometry. A new test-tube was washed and dried. The tube was filled with 5% 3-aminopropyltriethoxysilane. The 3-aminopropylsilylated surface was treated with glutaraldehyde and 5.6.10(-2) mg/ml solution of a normal mouse monoclonal antibody. The Schiff base between glutaraldehyde and the antibody was further reduced with 7.9.10(-3)% NaBH4. The tube was washed with 0.05% Tween 20 to block non-specific binding. The antibody immobilized on the surface was measured by an enzyme immunoassay based on a reaction of anti-mouse immunoglobulin G labelled with alkaline phosphatase, with which p-nitrophenol was produced from p-nitrophenylphosphate as a substrate. Meanwhile, various amounts of the antibody were immobilized on slide glasses in the same manner. The antibody on each surface was measured by Fourier transform infrared reflection spectrometry. The antibody immobilized under the final conditions was detectable by the enzyme immunoassay, and stable at 4 degrees C for ten days. The antibody on the slide glass was a unimolecular layer, as judged from the Fourier transform infrared spectra referred to -CONH- band semiquantitatively. Thus, we found the optimal conditions for immobilizing an ultra-thin layer of the monoclonal antibody on the glass surface.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
Centrifugal separation of low-concentration suspension in a biconical rotor of a centrifuge was modeled numerically. A system of equations describing the motion of solid particles in a fluid flow was constructed and solved. The effect of geometric parameters of the centrifuge rotor on the separation efficiency was demonstrated.  相似文献   

16.
The deposition of n-octylphosphonic acid on aluminum oxide was studied. The substrate was pretreated in order to achieve a root-mean-square roughness of <1 nm, a hydroxyl fraction of 30%, and a thickness of approximately 170 nm. It was proven using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) that, rather than a monolayer, an organic multilayer was formed. The growth mechanism was identified as a Stranski-Krastanov one. It was also shown that the use of AFM, probing the surface topography, is essential for a reliable quantification and interpretation of data obtained with XPS.  相似文献   

17.
本文研究大表面积的WO2.90[1]对丙烯的热脱附作用,并以丙烯和环己烯作为直链和环状烯烃的典型化合物,初步探讨其催化氧化性质。  相似文献   

18.
Mechanism of Thermal Decomposition of Barium Benzoate   总被引:4,自引:0,他引:4  
Barium benzoate was synthesized in a hydrothermal reaction. The complex was characterized by elemental analysis, IR spectroscopy and X-ray powder diffraction. It was monoclinic and had a layered structure. The mechanism of thermal decomposition of the barium benzoate was studied by using TG, DTA, IR and gas chromatography-mass spectrometry. In a nitrogen atmosphere, the barium benzoate decomposed to form BaCO3 and organic compounds: mainly benzophenone, triphenylmethane, etc.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
提出了电感耦合等离子体原子发射光谱法(ICP-AES)测定钒铁中硅、磷、铝、锰、镍、铬、铜、钛共8个杂质元素含量的方法。钒铁样品(0.5000g),先后加入50%(体积分数)硝酸溶液20mL及50%(体积分数)盐酸溶液10mL,在100℃左右加热溶解,溶解过程中应注意保持溶液体积在25mL左右。将溶液过滤并置于200mL容量瓶中作为母液留用。将滤纸及不溶物一并移入铂坩埚中,置于马弗炉中,先于250℃灰化20min,稍冷后加入无水碳酸钠和硼酸(质量比2∶1)组成的混合熔剂0.3g,升温至950℃融熔15min。冷却,用体积比1∶10的盐酸溶液10mL浸出熔块,将此溶液与上述母液合并并加水定容至200mL。此溶液供ICP-AES在仪器工作条件下进行分析。绘制校准曲线时,加入纯铁和五氧化二钒作为基体,以消除基体干扰,然后加入上述8种元素的标准溶液,并按上述溶液最终稀释体积条件和仪器工作条件制作曲线(R大于0.999)。为验证所提出的分析方法的测定数据的精密度,约请了10个实验室对8个不同含量水平的钒铁样品对方法作协同试验,按GB/T 6379.2-2004所规定的方法求算了重复性标准偏差Sr和重复性限r,以及再现性标准偏差SR和再现性限R,并求得所测定的8种元素在各自的测定范围内的r与w之间和R与w之间的函数关系,说明该方法有较好的稳定性和准确性,而且证明此方法是可行的。  相似文献   

20.
Introduction Theliverisoneoftheorgansthathaspotentialre generativecapabilityinmammaliananimals[1].Studies oncaninemodelshaveindicatedthatthelivercanre generate,inonlytwoweeks,toitsoriginalsize,after70%hepatectomy[2].Therefore,theresearchoncellu larandmole…  相似文献   

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