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41.
Surfaces of three types of CuZr-based bulk metallic glasses (BMGs) were modified by laser surface treatment (LST), and the influence of the treatment on structure and mechanical properties of these alloys was investigated. The phase structure of as-cast and laser-treated samples was characterized by XRD and the morphology of the alloys after fracture was examined by SEM. The compressive plasticity of treated Cu47.5Zr47.5Al5 and Cu46.5Zr47.5Al5Co1 BMGs can be improved from 0.5% to 2.0% and from 1.2% to 5.7% respectively compared with the as-cast ones, while (Cu0.55Zr0.40Al0.05)99Er1 BMG shows insignificant change of plasticity. The improvement in plasticity is attributed to induced crystallization of B2 CuZr phase in the treated surface zone of selected metallic glasses. 相似文献
42.
SONG Gang ZHANG Kai CHEN YuanYuan LIU HuiLi WU Chao YU Li XIAO JingHua 《中国科学:物理学 力学 天文学(英文版)》2013,(4):680-684
We successfully investigate an optical bistability phenomenon in a layered structure consisting of Kretschmann configuration involving the Kerr-type nonlinear and the silver film. Pure theoretical approaches are employed to investigate that the surface plasmon could easily be coupled and both the reflection and transmission curves versus the incident intensity forms optical bistability. The transmission curves are greatly influenced by the thickness of the second silver film. These results may be useful for designing novel surface plasmon-based optical devices and will be essential for future classical and quantum information processes. 相似文献
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Xian Tao Ke‐Cheng Shen Qing‐Yun Tang Meng Feng Jiang‐Tao Fang Yu‐Long Wang Ying‐Zhong Shen 《应用有机金属化学》2012,26(7):323-329
New N‐silver(I) acetylbenzamide complexes of type Ln?AgNC9H8O2 (L = PPh3; n = 1, 2a; n = 2, 2b; n = 3, 2c; L = P(OEt)3; n = 1, 2d; n = 2, 2e; n = 3, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, 1H NMR, 13C{H} NMR, 31P{H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry and crystallizes as cis–trans. New N‐silver(I) acetylbenzamide complexes have a four‐membered ring, which could influence their chemical and physical properties and modulate volatility. Metal organic chemical vapor deposition experiments were carried out successfully at 400°C and 450°C using 2e as precursor for the deposition of silver films, respectively. The high‐purity silver film obtained at 400°C is dense and homogeneous. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
45.
Shaoyong Ke Zhigang Zhang Ya-Ni Zhang Liqiao Shi Ronghua Zhou Aibing Jiang Ying Liang Ziwen Yang 《Research on Chemical Intermediates》2012,38(8):1827-1837
A novel series of ether functionalization of spiro-tetronic acid derivatives have been designed and conveniently synthesized via three steps, including esterification, one-pot heterocyclization, and etherification reactions. The target molecules have been identified on the basis of analytical spectra data. All newly synthesized compounds have been screened for their potential insecticidal activity against Heliothis armigera and Plutella xylostella compared with spirodiclofen by standard method. 相似文献
46.
通过比较多种杂多酸及铬酸盐等纯化剂的钝化效果,发现H3PMo12O40是一种优良的纯化剂。在55℃,pH1.0的条件下,A3钢在20g/L的H3PMo12O40溶液中能形成致密的耐蚀性保护膜。AES结合Ar^+溅射测得膜的元素组成为:P1.9%,Mo17.9%,O69.6%,Fe10.7%.XPS测得膜中Mo以Mo(Ⅵ)、Mo(V)t Mo(Ⅳ)三种氧化态存在。红外及Raman光谱表明,膜的主要振 相似文献
47.
A method of using the Bardeen-Cooper-Schrieffer (BCS) nuclear wave function to treat the two-nucleon mechanism for neutiinoless double beta decay process 0+ → 0+ is proposed.The neutrinoless decay mode and the neutrinoless decay accompanied by a Majoron emission mode of 82Se are studikd. Our cdculated results show that to reproduce the experimental value of γ(ov) > 1.8 × 1022 yr for neutrinoless double beta decai of 82Se the Majorana neutrino mass mv < 6.2 eV and the mixing parameter of right-handed current η < 7.0 × 10-6 In the emission with a Majoron mode the effective Majoron coupling to neutrino is deduced from the experimental value of γ(ov,H) > 4.4 × 1020 yr for 82Se with the result H0> < 6.2 × 10-4. 相似文献
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