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71.
Yousong Gu Dayong ZhangXiaoyuan Zhan Zhen JiYue Zhang 《Journal of magnetism and magnetic materials》2006
Series of [FePt(4min)/Fe(tFe)]10 multilayers have been prepared by RF magnetron sputtering and post-annealing in order to optimize their magnetic properties by structural designs. The structure, surface morphology, composition and magnetic properties of the deposited films have been characterized by X-ray diffractometer (XRD), Rutherford backscattering (RBS), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX) and vibrating sample magnetometer (VSM). It is found that after annealing at temperatures above 500 °C, FePt phase undergoes a phase transition from disordered FCC to ordered FCT structure, and becomes a hard magnetic phase. X-ray diffraction studies on the series of [FePt/Fe]n multilayer with varying Fe layer thickness annealed at 500 and 600 °C show that lattice constants change with Fe layer thickness and annealing temperature. Both lattice constants a and c are smaller than those of standard ones, and lattice constant a decreases as Fe layer deposition time increases. Only a slight increase in grain size was observed as Fe layer decreased in samples annealed at 500 °C. However, the increase in grain size is large in samples annealed at 600 °C. The coercivities of [FePt/Fe]n multilayers decrease with Fe layer deposition time, and the energy product (BH)max reaches a maximum in the samples with Fe layer deposition time of 3 min. Comparison of magnetic properties with structure showed an almost linear relationship between the lattice constant a and the coercivities of the FePt phase. 相似文献
72.
Sang Kyu Lee Min Ju Cho Jung‐Il Jin Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2007,45(3):531-542
New photocrosslinkable maleimide copolymers have been synthesized by the attachment of a tricyanopyrrolidene‐based chromophore. The 2‐(3‐cyano‐4‐(2‐{4‐[hexyl‐(6‐hydroxy‐hexyl)‐amino]‐phenyl}‐vinyl)‐5‐oxo‐1‐{4‐[4‐(3‐oxo‐3‐phenyl‐propenyl)‐ phenoxy]‐butyl}‐1,5‐dihydro‐pyrrol‐2‐ylidene)‐malononitrile chromophore exhibits nonlinear optical activity and contains a chalcone moiety that is sensitive to UV light (λ = 330–360 nm) for crosslink formation. The maleimide monomers have also been functionalized with chalcone moieties. The resultant copolymers exhibit great processability, and one of them shows a maximum electrooptic coefficient of 90 pm/V at 1300 nm. We could control the thermal stability of the electrooptic coefficient with the newly synthesized photoreactive copolymers successfully. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 531–542, 2007 相似文献
73.
Jiamin Jin 《Acta Physica Hungarica A》2006,27(2-3):237-240
This poster presents the PHENIX results on high-p Tγ-hadron and π0-hadron correlations and shows the modification of away side jet shape by the medium. By comparing their jet shapes and yields, we see some evidence of the direct γ contribution to correlation functions. 相似文献
74.
Tao Jin Feng-Xian Jiang Xiao-Li Li Fang Wang Xiao-Hua Shen Rui-Qiang Zhang Hai-Shun Wu 《Applied Surface Science》2006,253(5):2708-2712
CoPt/Ag and [C/CoPt]n/Ag thin films have been prepared onto the glass substrates by magnetron sputtering. We investigated the evolution of texture and magnetic properties of CoPt/Ag and [C/CoPt]n/Ag films. The results show that C-doping plays an important role in improving (0 0 1) texture, improving the order parameter S, reducing the intergrain interactions, and making the magnetization reversal mechanism more close to Stoner-Wolfarth rotational mechanism. The growth mechanism of (0 0 1) texture also seems to be related strongly to the films thickness. Our results show that the highly (0 0 1)-oriented films with ordered fct phase have a significant potential for the perpendicular media of extremely high-density recording. 相似文献
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光电效应是物理学中一个重要课问题,也是近代物理学几个重大的实验之一.一般物理学教材均要介绍光电效应.但是,在众多的教材中,对光电效应实验装置图的引入存在差异,有些有失科学性,因而引起广大物理学教育工作者的关注. 相似文献
78.
Jin Hu Gang Liu Jixiu Zhang Lingchao Kong Weidong Fei 《Applied Surface Science》2006,253(5):2792-2795
The microstructure of a laser treated Al18B4O33w/2024Al composite has been investigated using transmission electron microscope (TEM), low-angle (glancing angle) X-ray diffraction (XRD) techniques. Various surface microstructures were observed in the laser treated composite. The Al18B4O33 whisker on the surface of the composite was decomposed during laser surface melting, various decomposition products were studied in the laser treated composite. Eutectic phases and the precipitation in the matrix of the composite with laser-treated were observed. The main phases detected in the molten zone were aluminum and decomposition products Al2O3. The effect of laser treatment on the hardness of the composite was also examined. A surface hardness of 400 Hv was noted. 相似文献
79.
80.
Jian Ming ZHAN Bijan DAVVAZ K. P. SHUM 《数学学报(英文版)》2007,23(8):1345-1356
We describe the relationship between the fuzzy sets and the algebraic hyperstructures. In fact, this paper is a continuation of the ideas presented by Davvaz in (Fuzzy Sets Syst., 117: 477- 484, 2001) and Bhakat and Das in (Fuzzy Sets Syst., 80: 359-368, 1996). The concept of the quasicoincidence of a fuzzy interval value with an interval-valued fuzzy set is introduced and this is a natural generalization of the quasi-coincidence of a fuzzy point in fuzzy sets. By using this new idea, the concept of interval-valued (α,β)-fuzzy sub-hypermodules of a hypermodule is defined. This newly defined interval-valued (α,β)-fuzzy sub-hypermodule is a We shall study such fuzzy sub-hypermodules and sub-hypermodules of a hypermodule. generalization of the usual fuzzy sub-hypermodule. consider the implication-based interval-valued fuzzy 相似文献