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51.
First-principle calculations are performed to study the infrared optical and electronic properties of the tetragonal CaTiO3. We find that dielectric function and reflectivity exhibit a new single-peak infrared spectrum. It is shown that strong orbital hybridization can form the dipole distribution of covalent bonds (Ti-O1 and Ti-O2)and can result in anomalous optical behaviour. The tetragonal structure that determines the dipole configuration and leads to the optical dipole-dipole transition forbidden is therefore realized to be vital to cause such optical phenomena with the insulator feature. 相似文献
52.
兰州重离子加速器冷却储存环(HIRFL CSR)由一个主环(CSRm)和实验环(CSRe)构成.两个储存环的束流注入与引出都需要借助于切割磁铁的导向来完成.介绍了CSR的切割磁铁的物理设计和二维场计算. In order to satisfy the requirement of beam injection and extraction of CSR, four magnetic septums will be used in the accelerator. In the design, the shape of the lamination is optimized by 2-D magnetic field calculation. Also, in order to decrease the leakage field and obtain a satisfied field distribution, a special auxiliary coil and a shield iron plate are considered and as well as the construction of the septum leg is treated in a special way. As a result, the leakage field is almost... 相似文献
53.
介绍了EAST 装置上的384 道(极向24 道径向16 道)的外差混频式电子回旋辐射成像诊断系统及其在EAST 及其复杂的电磁环境中的运行情况。在低杂波电流驱动期间,高灵敏度的电子回旋辐射成像系统受到严重干扰以至于无法提供正确的实验数据。通过优化系统各模块的接地、外加多层铜网屏蔽等措施,使得ECEI 系统屏蔽效能与改善之前相比提高了40dB,基本保障了EAST 装置上电子回旋辐射成像诊断的正常工作。 相似文献
54.
ICP-AES法同时测定聚酯切片中的钛和铁 总被引:1,自引:0,他引:1
本文介绍ICP-AES法同时测定聚酯切片中钛和铁的方法。试样以干法分解,以硫酸,硫酸铵溶解残渣后进行测试。回收率为93.5%-100.6%,RSD<3.83% 相似文献
55.
Effects of Substrate Temperature on Helium Content and Microstructure of Nanocrystalline Titanium Films 下载免费PDF全文
Helium-charged nanocrystalline titanium films have been deposited by HeAr magnetron co-sputtering. The effects of substrate temperature on the helium content and microstructure of the nanocrystalline titanium films have been studied. The results indicate that helium atoms with a high concentration are evenly incorporated in the deposited titanium films. When the substrate temperature increases from 60℃ to 350℃ while the other deposition'parameters are fixed, the helium content decreases gradually from 38.6 at.% to 9.2at.%, which proves that nanocrystalline Ti films have a great helium storage capacity. The 20 angle of the Bragg peak of (002) crystal planes of the He-charged Ti film shifts to a lower angle and that of (100) crystal plane is unchanged as compared with that of the pure Ti film, which indicates that the lattice parameter c increases and a keeps at the primitive value. The grain refining and helium damage result in the diffraction peak broadening. 相似文献
56.
Two-dimensional numerical research on effects of titanium target bombarded by TEMPⅡ accelerator 下载免费PDF全文
Two-dimensional numerical research has been carried out on the ablation effects of
titanium target irradiated by intense pulsed ion beam (IPIB) generated by TEMP II
accelerator. Temporal and spatial evolution of the ablation process of the target
during a pulse time has been simulated. We have come to the conclusion that the
melting and evaporating process begin from the surface and the target is ablated
layer by layer when the target is irradiated by the IPIB. Meanwhile, we also
obtained the result that the average ablation velocity in target central region is
about 10\,m/s, which is far less than the ejection velocity of the plume plasma
formed by irradiation. Different effects have been compared to the different ratio
of the ions and different energy density of IPIB while the target is irradiated by
pulsed beams. 相似文献
57.
58.
Simulation of Helium Behaviour in Titanium Crystals Using Molecular Dynamics 总被引:1,自引:0,他引:1 下载免费PDF全文
The behaviour of helium in Ti crystals at 300 K has been investigated by means of the molecular dynamics. The study is focused on the influences of He-Ti interaction on the aggregation of helium atoms in the substrate. When a Born-Mayer potential is used to describe the He-Ti interaction, the He atoms are unable to cluster with each other due to the weak bridge barrier that cannot trap the helium atoms, Whereas using a He-Ti potential that is constructed by fitting the ab initio pairwise He-Ti potential, the clustering of He atoms can be observed. The results indicate that suitable He-Ti potential plays an important role in the formation of He clusters in metals. Moreover, it is noted that the shape of the formed He cluster is irregular, and the produced defect prefers to congregating on one side of the He cluster rather than spreading symmetrically around it. 相似文献
59.
Compact Single-Stage Femtosecond Multipass Ti:Sapphire Amplifier at 1 kHz with High Beam Quality 下载免费PDF全文
A compact femtosecond Ti:sapphire amplifier system is reported using single-stage multipass configuration with high beam quality. A high dispersion glass stretcher and a pair of double prisms for compression are introduced based on broadband femtosecond seed pulses. The non-grating-based pulse stretcher and compressor are advantageous to increase high beam quality and to reduce the high-order dispersion. A Gaussian filter is used to reduce the gain narrowing effect in amplification. The compact femtosecond Ti:sapphire nine-pass amplifier delivers pulses with a duration of 26 fs and an energy of 800μJ at 7mJ pumping pulses energy at I kHz. The 1-kHz femtosecond amplifier with high beam quality and high stability is very suitable for ultrafast physics research applications, such as attosecond science, ultra-precision micromachining, and THz wave generation. 相似文献
60.