铪-氘反应动力学研究

金属钛作为高真空环境下的贮氢材料，具有易氢脆和固氦能力差等固有缺陷。金属铪和钛同为VIB族元素，贮氢体积密度相近，但铪的吸氢体胀率（15％）远小于钛的（24%），因而可望在抗氢脆方面较钛有所改善。文中研究铪吸氘反应动力学，获得铪氘反应的速率常数和表观活化能，从而评价铪吸氘的动力学性能。     

Mg2Ni纳米贮氢合金电极的制备技术

以机械合金化法制备的Mg2Ni纳米粉末为原料采用以下3种方法制备电化学测试用电极：将Mg2Ni粉末与黏结剂的混合粉末调制成浆状涂敷于泡沫镍基体的两面，以一定的压力压制成片，形成三明治式夹层电极；利用模具先将混合粉末压制成圆片状，然后将其夹在两块泡沫镍基片中间以一定的压力压制成包覆型电极；利用模具先将混合粉末压制成圆片状，直接在片材表面焊上极耳，制作成圆片型电极。制备好的3种电极如图1所示。     

Mg2Ni纳米贮氢合金电极的电化学性能

测定了Mg2Ni纳米贮氢合金电极在扫描速率份别为10，20，40，80，160mV／s时的循环伏安曲线。从曲线上读出不同扫描速率时的阴极峰电流Ipc，阳极峰电流Ipa，阴极峰电势Epc，阳极峰电势Epa，数据列于表1。作Ipc-v^1/2关系图，如图1所示。     

金属Ti中He泡引起的缺陷行为

对金属Ti中He泡的长大行为进行分子动力学模拟，研究He泡周围的缺陷行为及其压力变化，分析He泡的生长机制。     

Fabrication processing effects on the microstructure and morphology of erbium film

The effect of substrate temperature on the microstructure and the morphology of erbium film are systematically investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). All the erbium films are grown by electron-beam vapor deposition (EBVD). A novel preparation method for observing the cross-section morphology of the erbium film is developed. The films deposited at 200°C have (002) preferred orientation, and the films deposited at 450°C have a mixed (100) and (101) texture, due to the different growth mechanisms of surface energy minimization and recrystallization, respectively. The peak positions and the full widths at half maximum (FWHMs) of erbium diffraction lines (100), (002), and (101) shift towards higher angles and decrease with the increasing substrate temperature in a largely uniform manner, respectively. Also, the lattice constants decrease with increasing temperature. The transition in the film stresses can be used to interpret the changes in peak positions, FWHMs, and lattice constants. The stress is compressive for the as-growth films, and is counteracted by the tensile stress formed during the process of temperature cooling to room temperature. The tensile stress mainly originates from the difference in the coefficients of thermal expansion of the substrate-film couple.     

第一性原理计算α-ScDx(D=H,He)的弹性常数

本文采用第一性原理方法研究了α相钪氢化合物(α-ScH _x )和α相钪氦化合物(α-ScHe _x )的弹性常数,其中x=0,1/4,1/8,1/32表示H原子和He原子在α-ScD_x(D=H,He)中的浓度.研究结果表明,对于钪,氢和氦对晶体的弹性性质的影响截然不同.钪氢化合物晶体的弹性常数基本上随着晶体中氢的浓度增加而增加,这跟实验测量得出的结论一致;然而,钪氦化合物体系的弹性常数几乎随着氦浓度的 关键词： 第一性原理 弹性常数 x')" href="#">α-ScH _x x')" href="#">α-ScHe _x     

Characterization of zirconium thin films deposited by pulsed laser deposition

Zirconium(Zr) thin films deposited on Si(100) by pulsed laser deposition(PLD) at different pulse repetition rates are investigated. The deposited Zr films exhibit a polycrystalline structure, and the X-ray diffraction(XRD) patterns of the films show the α Zr phase. Due to the morphology variation of the target and the laser–plasma interaction, the deposition rate significantly decreases from 0.0431 /pulse at 2 Hz to 0.0189 /pulse at 20 Hz. The presence of droplets on the surface of the deposited film, which is one of the main disadvantages of the PLD, is observed at various pulse repetition rates. Statistical results show that the dimension and the density of the droplets increase with an increasing pulse repetition rate. We find that the source of droplets is the liquid layer formed under the target surface. The dense nanoparticles covered on the film surface are observed through atomic force microscopy(AFM). The root mean square(RMS) roughness caused by valleys and islands on the film surface initially increases and then decreases with the increasing pulse repetition rate.The results of our investigation will be useful to optimize the synthesis conditions of the Zr films.     

钛吸／放氚的热力学特性

在金属测试系统上进行了钛（Ti）吸收和解吸氚（T）的热力学初步实验研究。加热氚化铀床，放出一定量氚气，记录平衡压力；加热样品至预定温度后恒温；将主管道中的氚气引入样品室，记录引入氚气后的平衡压，由系统中气体压力变化计算样品的吸氚量，以测定氚化过程中的p-C-T曲线。而解吸p-C-T曲线则是将接近饱和的样品温度恒定，记录平衡压力。关闭样品室阀门，用铀床回收管道里的气体后抽真空，然后再打开样品室阀门，让钛解吸，记录平衡压力，计算钛氚原子比。如此循环直至氚接近完全解吸。     

氢同位素化合物TiH2,TiD2和TiT2的电子振动近似理论方法

根据原子分子反应静力学和群论,确定TiH2,TiD2和TiT2的基电子状态为3A2.应用基函数6-311G**和密度泛函理论B3P86方法,全电子计算了氢同位素分子及其钛化物的能量E、定容热容Cv和熵S.应用电子振动近似理论,即用单个分子TiH2,TiD2和TiT2中的电子和振动能量和熵近似代表他们处于固态时的能量和熵. 计算所得到的金属钛的氢化热力学函数ΔH0,ΔS0,ΔG0以及平衡压力与温度的关系,与文献符合很好,这表明电子振动近似理论的可应用性,选用金属钛作为中子靶是很正确的.     

金属镱高压吸氘性能研究

大部分稀土金属与氢反应 ,都能很容易地生成三氢化物。但镱和铕却是例外 ,镱在氘压力小于 1 .0 3× 1 0 5Ｐａ时只生成二氘化物。文献报道金属镱在氢压力约为 2 .0ＭＰａ时生成ＹｂＨ2 .58,2 0 0～30 0℃等温线平台区从约ＹｂＨ2 扩展到接近ＹｂＨ2 .5,表明有两种不同的氢化物物相存在。基于ｖａｎ’ｔＨｏｆｆ计算得到ＹｂＨ2 .5(至二氢化物 )离解热约为 1 3.8ｋＪ/ｍｏｌＨ2 。对于在压力大于 0 .1ＭＰａ条件下获得的高含氢量氢化镱 ,Ｈａｒｄｃａｓｔｌｅ报道有一个ａ为 5 .1 92 的ｆｃｃ相与低氢含量的氢化物相共存[1 ] ,两个物相的存…