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1.
The microstructure of CosoNi22Ga28 ribbon with the L10 structure is examined. The band-like morphology is observed. These bands with the width in a range of 40-200 nm appear along the transverse direction of the ribbon. The giant magnetoimpedance (GMI) effect in this alloy is measured. The results show that Co5oNi22Ga28 exhibits a sharp peak of the GAI effect. The maximum GAH ratio up to 360% is detected. The GMI effect measured versus temperature shows large jumps of the magnetoimpedance amplitude at the reversal martensitic transformation temperature 240℃ and Curie temperature 375℃C respectively. The jump ratios of the magnetoimpedance amplitude examined at these temperatures are about 5 and 10, respectively.  相似文献   
2.
Electron momentum distributions for outer valence orbitals of CF2Cl2 have been obtained by (e,2e) electron momentum spectroscopy at an incident energy of 1200 eV + binding energy. The experimental electron momentum profiles are compared with Hartree-Fock and density functional theory (DFT) calculations using B3LYP hybrid functional with the 6-31G and 6-311+G* basis sets. Generally, the shapes of the experimental momentum profiles are well reproduced by DFT calculations using larger basis sets 6-311 + G*. An attempt has been made to clarify the ordering of the outer valence orbitals, which have been in controversy, by comparing experimental results with B3LYP/6-311 + G* calculations.  相似文献   
3.
阈值光电子一光离子符合速度成像技术通过对光电子和符合的光离子同时进行速度聚焦控制,大幅提高了电子和离子的收集效率和离子平动能分辨率,成为开展气相分子光电离和光电离.解离动力学研究的有效工具.利用该技术,我们精确地测量了分子的电离能、离子出现势等重要参数,并且开展了若干具有量子态或内能选择的离子解离动力学研究,描绘了相关势能面存在浅势阱等重要动力学特征,讨论了不同振动态和电子态的激发对解离机理和产物通道的重要影响.  相似文献   
4.

Background  

Recent data indicate that excitotoxicity of high levels of neurotransmitter glutamate may be mediated via programmed cell death (apoptosis) and that it can be prevented in HT22 mouse hippocampal cells by various equine estrogens with Δ8,17β-estradiol (Δ8,17β-E2) being the most potent. In order to delineate the mechanism(s), glutamate-induced cell death of HT22 cells was assessed by measuring (a) DNA fragmentation in the presence or absence of 11 equine estrogens (components of the drug CEE); (b) cell death and (c) levels of anti-apoptotic (Bcl-2) and proapoptotic (Bax) proteins in the presence or absence of two equine estrogens, Δ8,17β-E2 and 17β-estradiol (17β-E2) by LDH release assay and Western blot analysis respectively.  相似文献   
5.
A novel tandem one-pot method for the synthesis of polysubstituted pyridine derivatives has been developed via Knoevenagel-type reaction and subsequent 6π electrocyclization of the Blaise reaction intermediates and 3-formylchromones. Short reaction time, moderate to good yields and excellent functional group tolerance have been accomplished in this protocol.  相似文献   
6.
本文研究Fock-Sobolev空间上稠密定义算子,将这些算子统一表示成积分算子,利用积分算子的方法得到了它们的一个充分条件,并构造反例说此充分条件是非必要的,还得到这些算子为紧算子的两个充分条件.最后构造符号函数在复平面上每一点处本性无界的紧和Sp-类(0p∞)Toeplitz算子.  相似文献   
7.
Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) enantioselectivity.The re...  相似文献   
8.
With a sample of 58 Fermi/GBM GRBs detected before 2009 May, we compare the spectral properties of GBM GRBs with those detected by CGRO/BTASE and HETE-2. Our results show that the spectral index distributions are very consistent with those observed by BATSE. However, the E p distribution is quite different from that observed with BATSE and HETE-2. The GBM GRBs tend to be softer than the BATSE sample, but harder than the HETE-2 sample. This may be due to the instrumental selection effects and artificial sample effect on the BATSE sample. The distribution of the pseudo redshifts derived from the luminosity indicator based on the Amati-relation shows rough consistency with the spectroscopic redshifts of Swift GRBs. We estimate the detection rate of GBM GRBs with LAT based on the observed spectrum in the GBM band, and the inferred burst ratio of LAT detection with over 5 photons to GBM detection is 6%, yielding a detection rate pf 12 GRBs/yr with over 5 photons in the 1–300 GeV band. This is roughly consistent with the results in the first half year of Fermi operation. The low detection rate compared with theoretical predictions is a key for revealing the radiation mechanisms and particle acceleration of the prompt gamma-rays.  相似文献   
9.
This paper reports a class of bulk metallic glass including Ce-, LaCe-, CaLi-, Yb-, and Sr-based metallic glasses, which are regarded as glassy metallic plastics because they combine some unique properties of both plastics and metallic alloys. These glassy metallic plastics have very low glass transition temperature (Tg~25oC to 150oC) and low Young’s modulus (~20 GPa to 35 GPa). Similar to glassy plastics, these metallic plastics show excellent plastic-like deformability on macro-, micro- and even nano-scale in their supercooled liquid range and can be processed, such as elongated, compressed, bent, and imprinted at low temperatures, in hot water for instance. Under ambient conditions, they display such metallic properties as high thermal and electric conductivities and excellent mechanical properties and other unique properties. The metallic plastics have potential applications and are also a model system for studying issues in glass physics.  相似文献   
10.
This paper reports two new coordination polymers formed by carboxylate-substituted benzoimidazole and formate ligands: [Mn(L)·(HCO2)]n (1) and [Co(L)·(HCO2)]n (2) (L = benzoimidazol-1-yl-acetate). Com-plexes 1 and 2 are isomorphous and adopt a new 3,6-connected three-nodal topology showing inter-esting magnetic properties: spin canted antiferromagnetism for MnⅡ complex 1, but simple antiferro-magnetic coupling for CoⅡ complex 2.  相似文献   
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