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1.
ZnCl2/粘土-SA01催化剂上二苯甲烷的合成   总被引:6,自引:0,他引:6  
在环境友好ZnCl2/粘土-SA01催化剂上合成了二苯甲烷,较系统地考察了负载量、苯/苄基氯摩尔比、催化剂用量、反应温度、反应时间对该傅克反应的影响,并与催化剂的表面性质关联.实验结果表明,该催化剂具有良好的催化活性和稳定性并易于回收重复使用.  相似文献   
2.
以柠檬酸为配位剂,溶胶-凝胶法制备Ni2V2O7,采用X射线衍射、氮气物理吸附、电感耦合等离子体原子发射光谱、氢气程序升温还原、X射线光电子能谱和透射电子显微镜等技术对催化剂进行了表征.通过差热-热重分析,考察干凝胶分解为Ni2V2O7的温度以及分解过程的热效应并研究了不同焙烧温度与Ni2V2O7的形成、晶化程度之间的关系以及对丙烷氧化脱氢(ODH)制丙烯反应催化性能的影响.  相似文献   
3.
采用溶胶-凝胶法制备了钙钛矿型复合氧化物LaCoO_3, 并用沉积-沉淀法(DP法)制备了Au/LaCoO_3催化剂. 考察了制备条件对催化剂催化氧化CO活性的影响. 结果表明, 制备过程中, 溶液pH、 pH调节顺序及催化剂焙烧温度对催化剂活性均有一定影响. Au/LaCoO_3催化剂的最佳制备条件为: 沉积过程中在HAuCl4溶液中先加入载体后, 再调节溶液pH=8, 得到的催化剂经250 ℃焙烧后可提高催化剂稳定性.  相似文献   
4.
Friedberg, Lee and Zhao (FLZ) proposed a method for effectively evaluating the eigenenergies and eigen wavefunctions of quantum systems. In this work, we study several special cases to investigate applicability of the method. Concretely, we calculate the ground-state eigenenergy of the Hellmann potential as well as the Cornell potential, and also evaluate the energies of the systems where linear term is added to the Coulomb as a perturbation. The results obtained in this method have a surprising agreement with the traditional method or the numerical results. Since the results in this method have obvious analyticity compared to that in other methods, and because of the simplicity for calculations this method can be applied to solving the Schrödinger equation and provides us a better understanding of the physical essence of the concerned systems. But meanwhile applications of the FLZ method are restricted at present, especially for certain potential forms, but due to its obvious advantages, it should be further developed.  相似文献   
5.
Only one kind of synthesized alkaloid, piperlonguminine, was used to understand the interference of the other alkaloids in pharmacokinetic study using HPLC/UV in rat plasma after oral administration. Compared with the previous report, it was clarified that mixed alkaloids such as piperine and the other extract from Piper longum Linn did not interfere with the results. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
6.
离子交换法纳米Cu2O的制备及光催化性能的研究   总被引:3,自引:1,他引:2  
采用强酸性阳离子交换树脂(R—H),以CuSO4·5H2O为原料,制备出R2-Cu型阳离子交换树脂,R2-Cu型阳离子交换树脂与酒石酸钾钠进行离子交换得到Cu(OH)2,再用葡萄糖还原制得Cu2O纳米粒子,用IR、XRD、BET、TEM等手段对样品进行了表征,并以催化罗丹明B为模拟染料,日光(4月晴天,T=15~25℃)为光源,在自制的无色透明的玻璃反应器进行光催化降解反应,考察了Cu2O纳米粒子的催化性能.  相似文献   
7.
以硝酸铈、酒石酸铵为原料,采用络合均相沉淀法制备了CeO2纳米晶.研究了酒石酸铈络合物的形成和沉淀的操作方式等因素的影响.用XRD,TEM和SEM等测试方法对样品进行了表征.从样品的SEM照片可以看到形貌为蓬松泡沫状多孔性立体结构,经HRTEM观察小颗粒具有很清楚的晶格条纹,说明这些小颗粒为CeO2纳米晶.  相似文献   
8.
Friedberg, Lee and Zhao (FLZ) proposed a method for effectively evaluating the eigenenergies and eigen wavefunctions of quantum systems. In this work, we study several special cases to investigate applicability of the method.Concretely, we calculate the ground-state eigenenergy of the Hellmann potential as well as the Cornell potential, and also evaluate the energies of the systems where linear term is added to the Coulomb as a perturbation. The results obtained in this method have a surprising agreement with the traditional method or the numerical results. Since the results in this method have obvious analyticity compared to that in other methods, and because of the simplicity for calculations this method can be applied to solving the Schrodinger equation and provides us a better understanding of the physical essence of the concerned systems. But meanwhile applications of the FLZ method are restricted at present, especially for certain potential forms, but due to its obvious advantages, it should be further developed.  相似文献   
9.
A series of Au catalysts have been prepared at different pH using the Y-zeolites as support and the activity for CO oxidation has been tested. The results showed that the highest Au loading was obtained at pH = 6 and this catalyst demonstrated the highest activity.  相似文献   
10.
为研究Mg/Al比例对Mg-Al类水滑石(LDH)负载Au催化醇选择氧化的影响,采用共沉淀—水热晶化法合成了不同Mg/Al比的y Mg-Al LDH,采用液相还原法负载纳米Au颗粒.对样品进行XRD、N_2物理吸附、ICP-AES、AAS、TEM、CO_2-TPD、CO_2-In-situ DRIFTS和XPS等表征.在无附加碱条件下,Au/yMg-Al LDH催化剂催化1-苯乙醇选择氧化的催化活性随Mg/Al比增大呈现递增趋势,Au/4Mg-Al LDH活性最佳.载体表面弱碱性强度随Mg/Al比增大变化不大,弱碱位略有增多,对醇羟基脱氢有促进作用.载体层板Mg_3OH基团随Mg/Al比增大而增多有利于Au在层板边缘沉积,二者可形成有效协同,促进醇氧化过程进行.  相似文献   
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