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以美国NOVA和国家点火装置用的高功率脉冲氙灯为例,结合对神光Ⅲ装置用脉冲氙灯的分析,发现了影响脉冲氙灯失效的几个因素,包括石英灯管应力、氙灯尺寸、灯管微缺陷、电极溅射、灯头绝缘、氙气纯度、封接可靠性及周围氙灯放电。结果发现:在进灯能量相同的情况下,氙灯电极弧长越长,内径越大,寿命越高;石英灯管表面的静态拉应力、内表面的微缺陷以及周围氙灯的电离辐射使得氙灯的额外负载能量大大增加,这些是导致氙灯爆炸概率变大的直接因素。 相似文献
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采用循环伏安、方波伏安、计时电位和开路计时电位等电化学方法研究了Pr(Ⅲ)离子在LiCl-KCl-BiCl3熔体中W电极上的电化学行为。循环伏安和方波伏安的研究表明,Pr在预先沉积的Bi膜电极上发生欠电位沉积是由于生成了Pr-Bi金属间化合物,导致Pr(Ⅲ)在Bi膜电极上的还原电位比在W电极上还原电位更正。从开路计时电位曲线可以观察到两相共存的Pr-Bi金属间化合物的两个平台。利用开路计时电位计算了723-873 K温度范围内Pr在Pr-Bi合金中的活度和偏摩尔Gibbs自由能以及Pr-Bi金属间化合物的生成Gibbs自由能。通过恒电位电解,在液态Bi电极上得到了Pr-Bi合金,并采用X射线衍射(XRD)和扫描电子显微镜(SEM)附带能量散射谱(EDS)对样品进行了表征,结果表明所得到的Pr-Bi金属间化合物为PrBi2和PrBi。 相似文献
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A simple and convenient pressure calibration method is developed for a newly designed portable wide-access 'panoramic' cell. This cell is adapted to angle-dispersive-mode high-pressure in situ neutron diffraction of reactor neutron sources. This pressure calibration method has established a relationship between the cell pressure and the anvil displace- ment (gasket compression) based on the fixed-point calibration technique. By employing TiZr gasket with a thickness of 3 mm and WC anvil with a culet of 4 mm diameter, the average anvil displacements are 1.31 mm and 2.22 mm for Bi phase transitions (2.55 GPa and 7.7 GPa), and 1.85 mm for Ba phase transitions (5.5 GPa), respectively. In this pressure range, the pressure increases quickly with decreasing gasket thickness, and undergoes a linear increase with the anvil displacement. By extrapolating the calibration curve, the cell pressure will achieve 10 GPa when the anvil displacement is around 2.5 ram. 相似文献
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分别采用直接测量法、同位素交换法和溶解法测量铀床中的氚残留量, 并分析了这三种测量方法在本实验条件下的误差. 直接测量法测量铀床的氚残留量的结果如下: 铀床的氚残留量为2.68%, 即每克铀含(0.0308±0.0003) mmol 氚气; 当压力读数在1500~133332 Pa之间时, 基于理想气体状态方程的测量方法(简称PVT法)的标准差小于0.95%. 同位素交换法测量铀床氚的结果如下: 加热充分解吸过的铀床经多次同位素交换后, 其交换效率仅为2.84%, 即不到3%(摩尔分数)的氚被氘气载带出来, 其同位素交换法测量的标准差为7.35%. 溶解法能够彻底地测量铀床中残留的氚, 其溶解法测量的标准差为6.49%. 相似文献
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The diffusion barriers for the single helium atom in 3d transition metals are systematically studied by effective medium theory without any adjustable parameters. In the calculation, the relaxiation effects of lattice are taken into account. The comparison of our calculated results with the available experimental data and other theoretical values shows good agreement. 相似文献
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在从室温到500℃的温度范围内,用卢瑟福质子背散射技术分别测量了不同能量、不同剂量注入的纳米晶钛膜中氦的浓度分布,不同温度时的保持剂量及其释放浓度.发现氦在这种纳米晶粒膜中其氦-钛原子浓度比达到41%—52%时能在室温到100℃的温度下长期稳定保持,若其原子浓度达52%—74%时也能在室温环境有效保持.文中对这种具有大的界面体积比的膜能有效保持氦这种惰性元素的可能机理从能量观点进行了初步探讨.
关键词:
离子注入
纳米晶粒钛膜
氦
保持剂量 相似文献
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Tile stability of He in hep-Ti is studied using the a5 initio method based on the density functional theory. The results indicate that a single He atom prefers to occupy the tetrahedral site rather than the octahedral site. The interaction of He defects with Ti atoms is employed to explain the relative stabilities of He point defects in hcp-Ti. The relative stability of He defects in hcp-Ti is useful for He clustering and bubble nucleation in metal tritides, which provides the basis for development of improved atomistic models. 相似文献
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在自行建立的气-液催化交换装置上,用氢同位素氘代替氚研究了氘从气相到液相的催化交换过程。实验装置的流程图见图1。主要由催化交换柱、气体流量计、料液泵、贮液槽及控制系统组成。 相似文献