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1.
直接由SiO2低温合成含硅环氧化合物及其结构表征   总被引:9,自引:0,他引:9  
研究了直接由SiO2(沉淀白炭黑)、乙二醇、KOH为原料低温合成高活性的五配位有机硅络合物[KSi-(OCH2CH2O)2OCH2CH2OH]然后与环氧氯丙烷反应,生成含硅环氧化合物,并借助于红外、核磁共振、热分析、能谱元素分析等现代测试手段,对合成的产物进行了结构表征。  相似文献   
2.
Two novel mono-nuclear zinc(Ⅱ) complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis (EA) and X-ray Diffraction (XRD). The UV-vis spectra show the ligand-centered (LC) π-π* transitions and intra-ligand charge transfer (1ILCT) transitions,and the 1ILCT band red-shifts with the increasing number of aromatic amine groups in the ligands. Complex [Zn(L1)2](PF6)2 with an aromatic amine group in ligand shows a strong emission peak at 523 nm in the MeCN solution at 293 K and a blue-shifted band at 517 nm in the alcoholic glass at 77 K. However,for complex [Zn(L2)2](PF6)2 containing aniline dimer modified ligand,no apparent emission can be observed in the MeCN solution at room temperature due to a PET non-radiative decay pathway. Both of them show multiplicate redox processes based on oligoaniline and terpyridine units. The shifts of redox potentials also reflect the D-A interactions between the oligoaniline units and [Zn(TPY)2]2+ core.  相似文献   
3.
An acoustoelastic method for residual stress measurement in slightly orthotropic materials by using ultrasonic longitudinal and shear waves is presented. A shear transducer with small vibrator 2 × 2mm2 is developed and described, and the measurement of 2-D residual stresses in a seam welded plate was carried out by this method with the shear transducer developed.This project was supported by National Natural Science Fundation of China  相似文献   
4.
在水溶液条件下以六缺位的[H2P2W12O48)]12-和Eu髥为反应前躯体得到了1个新的多金属氧酸盐化合物[Eu3(H2O)17(α2-HP2W17O61)].5H2O(1),对其进行了元素分析、红外光谱、热重、荧光等表征,并用X-射线单晶衍射测定了它的晶体结构。化合物1含有双支撑的多阴离子簇[{Eu(H2O)7}2{Eu(H2O)3(α2-P2W17)}2]8-,并进一步通过Eu髥连接形成了延c轴方向的一维链。室温条件下的荧光光谱研究表明:化合物1显示了强的红光发射。  相似文献   
5.
自行研制的等离子体针在大气压下通过介质阻挡放电产生的等离子体,再由喷嘴处安装的漏斗形装置聚焦形成针状等离子体. 然后对针状等离子体的基本特性和杀Enterococcus faecalisE. faecalis)菌进行了研究,E. faecalis菌是一种引起完善充填根管再感染的主要微生物. 当等离子体针功率为5—28?W时,对等离子体的温度进行了测量,表明它不同于其他热杀菌方式. 通过改变等离子体针内电极末端注入的氧气量,发现适当的氧气量,不仅增加等离子体内含氧粒子的浓度而且对等离子体的长度影响也不明显. 实验表明最佳参数为功率15?W,0.1?m3·h-1氦和2.5%氧气,间距12?mm,处理时间30 s. 为了找出杀菌的关键粒子,进一步比较了大气压下的等离子体针的发射光谱与agar(琼脂)2?mm下的光谱并找出关键粒子. 关键词: 大气压等离子体 介质阻挡放电 E. faecalis菌')" href="#">E. faecalis菌 光谱  相似文献   
6.
Germanium is a promising high-capacity anode material for lithium ion batteries, but it usually exhibits poor cycling stability because of its huge volume variation during the lithium uptake and release process. A double protection strategy to improve the electrode performance of Ge through the use of Ge@C core-shell nanostructures and reduced graphene oxide (RGO) networks has been developed. The as-synthesized Ge@C/RGO nanocomposite showed excellent cycling performance and rate capability in comparison with Ge@C nanoparticles when used as an anode material for Li ion batteries, which can be attributed to the electronically conductive and elastic RGO networks in addition to the carbon shells and small particle sizes of Ge. The strategy is simple yet very effective, and because of its versatility, it may be extended to other high-capacity electrode materials with large volume variations and low electrical conductivities.  相似文献   
7.
We report on Raman scattering of VO2 films prepared by radio frequency magnetron sputtering under different conditions. Our investigations revealed that the dominated Raman peaks shift towards high frequency for both V-rich and O-rich VO2 films, compared with the stoichiometry VO2 films. The experimental evidence is presented and the cause for nonstoichiometry dependence of Raman spectra of VO2 films is discussed.  相似文献   
8.
1 INTRODUCTION In the latest ten years, the structure and function of water clusters have captured the interest of chemists. One of the most important study objects in water cluster is to describe the behavior of water so- lution quantitatively at molecule level, which will pave the way for the solving of some environmental and other scientific problems, such as the formation of acid rain and nucleation mechanism of little water drop. Besides, weak interaction in water clusters could be al…  相似文献   
9.
方解石纳米孔隙内二氧化碳毛细凝聚的分子模拟   总被引:1,自引:0,他引:1  
在二氧化碳地质封存、增产非常规油气以及孔隙材料表征测量方面,纳米孔隙中二氧化碳相态的准确预测具有重要意义.然而,由于纳米尺度下毛细力、分离压等作用力占据主导因素,流体在孔隙中的相行为与体相流体存在根本不同.已有实验和模拟表明,Kelvin毛细凝聚理论无法预测特征尺度10 nm下的,孔隙内流体凝聚压力与体相饱和蒸气压的偏...  相似文献   
10.
分立式色散补偿拉曼放大器具有兼顾色散补偿和信号放大的特点,在通信系统中展现出广阔的应用前景.对反向抽运的C波段色散补偿分立式拉曼放大器的增益谱形状,增益饱和及受激布里渊散射等特性进行了较为详细的实验研究. 关键词: 分立式色散补偿拉曼放大器 增益饱和 受激布里渊散射 斯托克斯波  相似文献   
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