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柠檬酸法制备复氧化物材料的配位结构化学   总被引:1,自引:1,他引:0  
柠檬酸法在复氧化物材料制备中占有重要地位,它具有分散均匀、制备温度低、产物粒径小的特点.以特定组成和结构的柠檬酸络合物为前驱体,直接分解可得到纯度较高的复氧化物,从中可以了解复氧化物的形成过程.本文从配位结构化学的角度,评述以钛、钒、钼和钨柠檬酸络合物为前驱体制备复氧化物材料的研究进展.  相似文献   
84.
The rapid transition between spherical and γ-soft shapes in Zn isotopes in the mass A 70 region,is analyzed using excitation spectra and collective wave functions obtained by diagonalization of a five-dimensional Hamiltonian for quadrupole vibrational and rotational degrees of freedom,with parameters determined by constrained self-consistent relativistic mean-field calculations for triaxial shapes.The microscopic potential energy surfaces,together with the characteristic collective observables,illustrate a ...  相似文献   
85.
麻黄素和左旋咪唑显微拉曼测试分析   总被引:5,自引:0,他引:5  
在可见光激发下,利用显微拉曼技术得到了黄素和左旋旋咪唑的拉曼谱,并将它们的拉曼谱和甲基安非地明做了对比分析,麻黄素和甲基安非他明同属单取代苯,其分子结构十分相似,由于取代基的成分不同一样,因而拉曼谱中一些峰的相对强度和位置发生了变化。左旋咪唑由于取代基上为咪唑亚塞唑,其拉曼谱中主要谱线位置和强度明显不同于麻醉黄素和甲基安非他明。实验结果表明,利用显微拉曼技术在短时间内,对致幻药物进行准确快速的检测分析,将这一技术应用于运动比赛中,有助于对参赛人员服用违禁药物的检测和分析。  相似文献   
86.
This paper reports observations of significant synergistic effects between dielectric barrier discharge (DBD) plasmas and Cu-ZSM-5 catalysts for C2H4 selective reduction of NOx at 250℃ in the presence of excess oxygen by using a one-stage plasma-over-catalyst (POC) reactor. With the reactant gas mixture of 530 ppm NO, 650ppm C2H4, 5.8% 02 in N2and GHSV = 12000h^-1, the pure catalytic, pure plasma-induced (discharges over fused silica pellets) and plasma-catalytic (in the POC reactor) NOx conversion are 39%, 1.5% and 79%, respectively. The in-situ optical emission spectra of the reactive systems imply some short-lived active species formed from plasma-induced and plasma-catalytic processes may be responsible to the observed synergistic effects in this one-stage POC system.  相似文献   
87.
 报导了InGaAs/GaAs 和InGaAs/AlGaAs 垂直耦合量子结注入式激光器的制备工艺及其光致荧光谱, 量热吸收谱和电致荧光谱的特性。该激光器的连续波发光功率在室温下可达1W。  相似文献   
88.
Fe(II) was deposited into the bottom of the mesopores of highly ordered large caged cubic mesoporous silica by electrodeposition. And the deposited Fe mesoporous silica thin film was treated by 1%―4% HF to remove the SiO2 template and then calcined. It was found that nanowire bundles, dendritic plates of porous iron oxide, dense parallel backbones of porous iron oxide were obtained at 1.4―-1.6 V and 0.08―0.1 mol/L electrolyte concentration after calcinations; the dendritic pattern of porous iron oxide film ...  相似文献   
89.
本文在一维海森堡模型的基础上,采用界面参数化方法,研究了非周期性边界条件下,铁磁/反铁磁双层薄膜中自旋波低温激发问题.重点讨论了表面各项异性对薄膜中自旋波谱、色散关系的影响.结果表明:表面各向异性对铁磁层中自旋波谱影响较大,对色散关系影响甚微。  相似文献   
90.
The Editors of this special issue and the partners of the QSTRUCT European Network are deeply saddened by the news of Gilbert Grynberg's departure. It was Gilbert's vision which first brought together specialists in optical and atomic physics to form the research field of quantum structures and to found the QSTRUCT Network. Within the Network, Gilbert worked tirelessly to promote collaboration and the exchange of new ideas. He was particularly popular with young researchers, who appreciated his eagerness to share ideas and who were inspired by his clarity of thought. It was Gilbert who first proposed a special issue of EPJ D dedicated to quantum structures. Sadly he will not see its publication. We remember a special scientist and educator, a colleague who was passionate about physics but brought his infectious sense of fun to all who worked with him. Even in the face of great hardships he remained a vibrant and enthusiastic member of our scientific family. We will all miss him.  相似文献   
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