多金属氧酸盐α-Na6H[GeW9Fe3(H2O)3O37]·16H2O的合成和光谱

合成了多金属氧酸盐α-Na6H[GeW9Fe3(H2O)3O37]16H2O，通过元素分析、红外、紫外、光电子能谱、极谱和穆斯堡尔谱等手段进行了表征，并讨论和研究了该配合物的谱学性质。     

Low-Temperature Growth of Polycrystalline silicon Films by SiCl4／H2 rf Plasma Enhanced Chemical Vapour Deposition

Polycrystalline silicon film was directly fabricated at 200℃ by the conventional plasma enhanced chemical vapour deposition method from SiCl4 with H2 dilution. The crystallization depends strongly on the deposition power.The maximum crystMlinity and the crystalline grain size are over 80% and 200—50Onm, respectively. The results of energy dispersive spectroscopy and infrared spectroscopy measurements demonstrate that the film is mostly composed of silicon, without impurities such as Cl, N, C and bonded H. It is suggested that the crystallization at such a low temperature originates from the effects of chlorine, i.e., in-situ chemical, etching, in-situ chemical cleaning, and the detachment of bonded H.     

用锌有机源和CO2/H2混合气源PECVD沉积ZnO薄膜

在等离子体作用下,以CO2/H2混合气为氧源,Zn(C2H5)2锌为锌源,在单晶硅上生长出高度择优取向的氧化锌薄膜。X射线衍射分析表明,薄膜为六方结构,c轴高度择优;原子力显微镜观察到晶粒是有规律地按六方排布,薄膜的表面粗糙度较小;从光致发光谱还发现在380 nm处有非常强的紫外峰。     

机械密封焊接金属波纹管膜片结构的有限元分析

在Linux操作平台下应用FAST_wmg有限元前后处理软件对机械密封焊接金属波纹管膜片建立了有限元模型并进行了非线性有限元分析．在同等条件下对焊接金属波纹管采用了S型膜片和V型膜片，并分别进行了有限元强度评价和对比分析．结果表明，两种膜片最大应力集中都在膜片两端周围发生．这与文献所叙述的波纹管的主要失效发生在膜片两端与焊谷接近的部位非常吻合，但是，在同样边界条件下，在同样位移量时S型膜片最大应力值比V型膜片最大应力值小，压缩量大．     

一节"金属"双语课

上海市的二期课改已经进入了第4个年头,对化学学科知识的要求有一定降低,但更加注重学生的综合能力的提高。本节双语课的内容涉及金属的性质和用途,让学生体会“结构决定性质,性质决定用途”这句话的含义。学习内容与学生生活非常接近,知识性不是特别高深,可发挥上海学生英语水     

Effect of Incident Intensity on Films Growth in Pulsed Laser Deposition

Incident intensity, defined by the amount of particles deposited per pulse, is an important parameter in the film growth process of pulsed laser deposition （PLD）. Different from previous models, we investigate the irreversible and reversible growth processes by using a kinetic Monte Carlo method and find that island density and film morphology strongly depend on pulse intensity. At higher pulse intensities, lots of adatoms instantaneously diffuse on the substrate surface, and then nucleation easily occurs between the moving adatoms resulting in more smaller-size islands. In contrast, at the lower pulse intensities, nucleation event occurs preferentially between the single adatom and existing islands rather than forming new islands, and therefore the average island size becomes larger in this case. Additionally, our results show that substrate temperature plays an important role in film growth. In particular, it can determine the films shape and weaken the effect of pulse intensity on film growth at the lower temperatures by controlling the mobility rate of atoms. Our results can match the related theoretical and experimental results.     

SiO2-羟基表面上金属原子的第一性原理研究

采用第一性原理方法研究了SiO2-羟基表面上几种金属原子的吸附性质,发现In和Ga在SiO2-羟基表面上的结合很弱,而Fe,Co,Ni在该表面上与Si,O形成强的化学键.等势能面和扩散势垒计算表明In(Ga)的扩散激活能只有0.1-0.3 eV,表明这两种原子容易在表面上扩散.这些结果可以定性地解释纳米合成中的一些实验现象.     

电沉积制备金属超细Cu粉的研究

探讨了超细铜粉电沉积制备过程中阴极电流密度对粉体粒径的影响机制。结果表明:电流密度的改变对阴极过电位影响显著,电流密度从0.04A/cm2变化到0.1 A/cm2时,过电位从4.08V变化到9.96V;而过电位的变化直接引起粉体粒径的变化,粒径从大约50nm变化到700nm。分析表明,高电流密度可以获得较高的阴极过电位;在高的阴极过电位条件下,新核的生成速率高且稳定存在的晶核临界半径小,使得粉体粒径变细。     

EACVD中用氢原子谱线测定电子平均能量

采用蒙特卡罗方法，对EACVD中氢原子的发射过程进行了模拟。给出了由氢原子谱线测定电子平均能量的方法，结果对EACVD生长金刚石薄膜过程中实时监测电子平均能量，进而可以有效地控制工艺条件，生长出高质量的金刚石薄膜具有重要意义。     

A Convenient Synthetic Method of Metal Dendritic Porphyrins

Metal porphyrins are natural antioxidant reagent1-3. However, due to the characteristics of structures, they are only soluble in inorganic acids and part of polar organic solvents. Thus, it is limited to be used as effective pharmaceutical preparations. T…