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351.
为了分析ITER第一壁模块试制过程中Be/Cu界面经热等静压扩散连接后出现的不可接受的大尺寸缺陷,对Be/Cu连接失效的模块进行了破坏性试验.首先采用线切割对模块进行解剖,并对连接界面缺陷区域及非缺陷区域通过金相观察、SEM观察及能谱分析进行对比,初步确定了界面连接的失效机理. 相似文献
352.
K. Yasutake H. Ohmi M. Shimizu A. Takeuchi H. Kakiuchi K. Yoshii Y. Mori 《Applied physics. B, Lasers and optics》2000,71(6):787-793
A velocity spectrometer for a neutral atomic beam has been developed to prepare a monovelocity atomic beam. In order to disperse
a relatively fast atomic beam according to its longitudinal velocity, a magnetic quadrupole lens with a large magnetic gradient
has been used. The device was made using NdFeB permanent magnets. The magnetic gradient in the quadrupole was measured to
be sufficiently large (1 T/cm) and uniform along the radial direction. The resonance fluorescence spectra of the Li atomic
beam after passing through the magnetic quadrupole lens have been measured by using a single-mode tunable laser. From the
peak shift of the fluorescence spectrum, the exerted force on Li atoms by the magnetic lens was 8160 times as large as the
acceleration of gravity. Using the present spectrometer, we have measured the longitudinal velocity distribution of the thermal
Li beam at 800 °C, which was in good agreement with the result from the fluorescence spectra. It is expected that a monovelocity
Li atomic beam of 1000 m/s with a velocity spread narrower than 1% can be easily formed with a compact experimental arrangement
using the developed velocity spectrometer. In this case, the available flux given as a fraction of the incident Li flux is
estimated to be about 1%. A high-velocity resolution of 0.03% is expected at the available fractional flux of about 0.01%.
Received: 5 June 2000 / Revised version: 14 August 2000 / Published online: 8 November 2000 相似文献
353.
U.V. Poulsen K. Mølmer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,11(2):151-157
We present theoretical calculations for the reflection of atoms from a magnetic surface with a sinusoidal magnetization. A
fully quantum mechanical treatment is possible because the problem may be reduced to an effective one-dimensional one. Results
of numerical wave-packet calculations are presented and compared with an analytical model in which the atoms separate into
different internal state components which follow classical paths in different potentials.
Received 21 October 1999 and Received in final form 18 January 2000 相似文献
354.
355.
本文研究使用HF、HCl、HNO3、HClO4 4种酸溶解样品,ICP-AES测定样品中的Be.对国家一级标样进行测定,测定结果与标准样品值一致,方法检出限Be为0.10μg/g.此方法简便、快速、准确. 相似文献
356.
对ITER屏蔽包层第一壁板铍铜连接件在高热负荷作用下的传热性能进行了分析,模拟了第一壁铍铜连接手指部件的热应力和热应变,得到其对应的热疲劳寿命.计算结果表明,在局部4.7MW?m-2高热负荷作用和ITER水冷条件下,现有设计方案中的铍铜连接件的热性能和热疲劳性能均满足设计要求. 相似文献
357.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
358.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
359.
An efficient photoelectrode is fabricated by sequentially assembled CdS and CdSe quantum dots (QDs) onto a ZnO-nanowire film. As revealed by UV-vis absorption spectrum and scanning electron microscopy (SEM), CdS and CdSe QDs can be effectively adsorbed on ZnO-nanowire array. Electrochemical impedance spectroscopy (EIS) measured demonstrates that the electron lifetime for ZnO/CdS/CdSe (13.8 ms) is calculated longer than that of ZnO/CdS device (6.2 ms), which indicates that interface charge recombination rate is reduced by sensitizing CdSe QDs. With broader light absorption range and longer electron lifetime, a power conversion efficiency of 1.42% is achieved for ZnO based CdS/CdSe co-sensitized solar cell under the illumination of one Sun (AM 1.5G, 100 mW cm−2). 相似文献
360.
An efficient pulsed CH3OH terahertz (THz) laser pumped by a TEA CO2 laser is investigated experimentally. To improve photon conversion efficiency and THz laser energy, two cavity configurations of the TEA CO2 laser, which is external and semi-external, are evaluated. The pump intensities are about 4.7 MW/cm2 and 1.2 MW/cm2, respectively. Higher pump intensity and more stable single lines are obtained in the external cavity. For the 3.8 J pump energy of the 9P(16) transition in the external cavity, the maximum terahertz output energy with 570.5 μm wavelength at 160 Pa is 431 μJ. With a 6 J energy pulse in terms of a semi-external cavity, a 353 μJ terahertz emission (570.5 μm) is produced. The corresponding photon conversion efficiencies are 1.36% and 0.705%, increasing by a factor of about 2. 相似文献