Characterization of EBPVD micro-layer composites and simulation of its internal stress state

Based on the basic operating principal and the technology characteristic of electron beam physical vapor deposition(EBPVD) technique, EBPVD was used to prepare the micro-layer composites. The effect on the substrate preheating temperature was taken into accounts and the finite element analysis package ANSYS was used to simulate the internal stress field and the potential displacement changing tendency. The results show that one of the most important quality factors on the judgment of micro-layer composites is the adhesion between the substrate and the deposition layers as well as among the different deposition layers. Besides the existance of temperature gradient through the thickness of layers, the main reason for the internal stress in micro-layer composites is the mismatch of various properties of the layer and the substrate of different thermal expansions and crystal lattice types. With the increase of substrate preheating temperature, the inter-laminar shear stress also takes on a tendency of increase but the axial residual stress decrease.     

纳米碳管的电子衍射及其螺旋度测量

本文对电弧放电和催化剂热解碳氢气法制备的多层直形纳米碳管的倒空间及其螺旋度，采用电子衍射进行了研究。结果表明：尽管制备方法不同，两类多层管的结构相似，皆由螺旋和非螺旋的单层石墨管组成；对其倒空间的分析以及系列倾转电子衍射实验证明，衍射图中测得的表观螺旋度值随和射条件而改变，只有在垂直入射条件下该值才代表碳管的真实螺旋度；     

用单透镜变换由多模光纤出射的大功率Nd：YAG激光束的特性

根据理论假设，通过选取单透镜的参数和位置，计算说明了单透镜使经由多模光纤出射的大功率Ｎｄ：ＹＡＧ激光束的发射角压缩，光束聚焦效率提高，光束截面场为高斯分布；文中的计算结果符合已知规律，从而说明了理论假设的正确性。     

电子束、离子束与蓝宝石相互作用的研究

研究了电子束、离子束作用于Al2O3表面时成分的变化，表明无论电子束或离子束都能使Al2O3发生分解，产生导电的元素Al。实验在PHI610·SAM上进行，电子束轰击下（3keV，O．5μA，入射角60°）10s就有元素Al分解出来，2min以后就达到饱和，分解析出量随时间成a（1－e－bt）的关系。离子束轰击下同样发生元素Al的分解，但当Ei＞3keV时，由于剥离速率加大，溅射5min时表面Al峰反而比1min时要弱。这时表面Al含量处于分解析出与溅射剥离的动态平衡中。实验还发现了Al2O3的解析与表面成分有关（如碳的含量）。最后讨论电子束与离子束的解析机理。     

反应离化团束（RICB）法生长CN硬质薄膜

用反应离化团束（ＲＩＣＢ）法，以低分子量聚乙烯为蒸发材料，氨气为反应气体，在ＮａＣｌ（１００）和Ｓｉ（１００）衬底上淀积Ｃ－Ｎ薄膜，透射电子衍射（ＴＥＭ）分析表明薄膜中含有β－Ｃ３Ｎ４晶粒，Ｘ射线光电子谱（ＸＰＳ）和红外吸收谱（ＩＲ）表明存在Ｃ，Ｎ原子的化学键合。     

A portable cryo-storage system for low-temperature scanning electron microscopy,suitable for international transport of cryo-specimens

A cryo-specimen storage system for low-temperature scanning electron microscopy (LTSEM) specimens is described, which: liberates multi-specimen experiments from sampling restrictions imposed by the rate at which LTSEM specimens can be examined in the SEM; provides security against experiment loss resulting from breakdown of the SEM or cryo-system; enables collection of specimens in the field or in laboratories remote from the SEM laboratory; and facilitates international air transport of LTSEM specimens. The components of the system, which has a capacity of 98 stub-mounted specimens, are readily made in a laboratory workshop. The details of the design may be altered to suit particular specimen types or experimental approaches.     

PVDF中空纤维滤膜的形态结构

用Ｌ－Ｓ相转换法制备了聚偏氟乙烯（ＰＶＤＦ）中空纤维不对称滤膜。铸膜液由聚合物、溶剂和添加剂组成。用电子显微镜（ＳＥＭ）考察了聚合物浓度、添加剂用量及种类对膜形态结构的影响。实验结果表明，聚合物浓度对膜形态结构有显著影响，当铸膜液中聚合物浓度较低时，无论用什么种类添加剂，都能形成大、且多的孔，但孔的形状随添加剂不同而异。当恒定聚合物浓度时，添加剂的用量对膜形态结构有很大的影响，但孔的大小及多少与添加剂含量的多少不成正比。     

电子自旋共振在橡胶研究中的应用

综述了电子自旋共振在橡胶的合成、加工和应用领域的应用现状及其发展前景。     

氮化钛薄膜的高分辨AES谱和XPS谱研究

着重讨论了TiNx薄膜俄歇电子谱的定量分析方法和X射线光电子谱中线形的变化。利用已知组元强度定量分析技术和Ti的LMV俄歇电子峰，探讨TiNx薄膜中N含量的定量方法。由该方法给出的定量结果与X射线光电子谱定量结果相一致。同时，利用X射线光电子谱测定了TiN和Ti2N2p轨道的结合能。并针对Ti2p峰形随N含量的变化，给出新的解释。     

Electrical characterization of very-narrow-gap bulk HgCdTe single crystals by variable magnetic field hall measurements

Variable-magnetic-field Hall measurements (0 to 1.5 T) are performed on very-narrow-gap bulk-grown Hg_1−xCd_xTe single crystals (0.165 ≤ x ≤ 0.2) at various temperatures (10 to 300K). The electron densities and mobilities are obtained within the one-carrier (electrons) approximation of the reduced-con-ductivity-tensor scheme. The present data together with the selected data set reported by other workers exhibit a pronounced peak when the electron mobility is plotted against the alloy composition x-value which has been predicted to be due to the effective-mass minimum at the bandgap-crossing (E_g ≈ 0). The observed position (x ≈ 0.165), height (≈4 x 10² m²Vs), and width (≈0.01 in x) of the mobility-peak can be explained by a simple simulation involving only ionized-impurity scattering. A lower bound of the effective mass is introduced as a fitting parameter to be consistent with the finiteness of the observed electron mobility and is found to be of the order of 10⁻⁴ of the mass of a free electron.