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991.
Guoping Dong Xiudi Xiao Xiaofeng Liu Bin Qian Yang Liao Chen Wang Danping Chen Jianrong Qiu 《Applied Surface Science》2009,255(17):7623-7626
Face-centered cubic Ag porous films have been prepared directly from the heat treatment of AgNO3-doped poly(vinyl alcohol) (PVA) electrospun nanofibers. Using Rhodamine B (RB) as the probing molecule, the surface-enhanced Raman scattering (SERS) effect of Ag porous films was demonstrated. The antibacterial activity of Ag porous films was also studied in this work. The propagation and biological activity of yeast cells were effectively inhibited by Ag porous films. These functional Ag porous films were expected to be applied in many fields, such as catalysis, diagnostics, sensors and antibacterial, etc. 相似文献
992.
Fabrication and magnetic properties of Ni-Zn nanowire arrays 总被引:2,自引:0,他引:2
Lihu Liu Haitao Li Shenghua Fan Jianjun Gu Yaopeng Li Huiyuan Sun 《Journal of magnetism and magnetic materials》2009,321(20):3511-3514
Ni-Zn nanowire arrays, with diameters of approximately 60 nm and lengths of around 40 μm, were fabricated by electrodeposition in porous anodic aluminum oxide templates at different electric potentials. X-ray diffraction observations demonstrated that the isolated nanowires had polycrystalline structure and that their phases changed with the deposition potential. The amount of deposited zinc in the nanowires increased with the deposition potential, whereas the amount of nickel decreased. Magnetic measurements showed that there was a gradual change of magnetism from isotropic to anistropic with increasing potential amplitude and that the coercivity reached a maximum value in the nanowire deposited at −1.35 V. 相似文献
993.
OH−-doped KBr polycrystals were colored electrolytically by using a pointed cathode and a flat anode. Characteristic O−, OH−, U, Cu+ and absorption peaks were observed in resolved absorption spectrum of uncolored polycrystals. Herein the position of the absorption peak at room temperature was determined by using a Mollwo-Ivey plot. Characteristic V2, V3, Cu+, , I2 and F spectral bands were observed in Kubelka-Munk functions of colored polycrystals. Current-time curve for electrolytic coloration of an OH−-doped KBr polycrystal and its relationship with electrolytic coloration process were given. Formation and conversion of color centers were explained. 相似文献
994.
Pseudobinary high Pr-content Tb1−xPrx(Fe0.4Co0.6)1.93 (0.70≤x≤1.00) magnetostrictive alloys have been fabricated by a melt-spinning method. The effects of the composition, spinning, and annealing processes on the structure, thermal stability, and magnetic properties are investigated. At a wheel speed of v≤30 m/s, the as-spun ribbons consist of a mixture of (Tb,Pr)(Fe,Co)2 cubic Laves phase and some non-cubic phases. A single (Tb,Pr)(Fe,Co)2 phase with MgCu2-type structure is formed with the process for the speed of v≥35 m/s and subsequent annealing at 500 °C for 30 min. The lattice parameter of the Tb1−xPrx(Fe0.4Co0.6)1.93 Laves phase increases from 0.7354 nm for x=0.70 to 0.7384 nm for x=1.00 and approximately follows the linear Vegard's law. The Curie temperature decreases, while the saturation magnetization increases as increasing Pr content. The Pr-rich alloys possess the relatively lower coercivity and the faster saturation of magnetostriction as compared with the Tb-rich alloys, which can be understood by their lower magnetic anisotropy. 相似文献
995.
New equation for deriving pure state density operators by Weyl correspondence and Wigner operator 下载免费PDF全文
By virtue of the completeness of Wigner operator and Weyl
correspondence we construct a general equation for deriving pure
state density operators. Several important examples are considered
as the applications of this equation, which shows that our approach
is effective and convenient for deducing these entangled state
representations. 相似文献
996.
Some necessary and sufficient conditions for a Banach space to be K-smooth or Kstrongly smooth are obtained. 相似文献
997.
The multi-scale analysis of fracture toughness of ferroelectric ceramics under complicate mechanical–electrical coupling effect is carried out in this paper. The generalized stress intensity factor (SIF) arising from spontaneous strains and polarization transformation in switching domain zones is accurately obtained by using an extended Eshelby theory. Taking BaTiO3 ferroelectric ceramic for example, it is discovered that the crack propagation can be induced by domain switching arising from negative electrical field when the crack surface is parallel to the isotropic plane, and the obtained critical electric displacement intensity factor (EDIF) approximates closely to that obtained by the Green’s function method. Additionally, as pinning dislocations and slip dislocations can strongly influence properties of ferroelectric devices and induce the property degradation, it is necessary to investigate the dislocation toughening effects on fatigue and fracture mechanisms. The results show that the dislocation shielding and anti-shielding effects on mode II SIF, mode I SIF and EDIF are obviously different when a dislocation locates at a position near the crack tip. Through the calculation of the critical applied EDIF for crack propagation by using mechanical energy release rate (MERR) theory, it is discovered that the slip angles obviously influence fracture toughness, and the mode II SIF arising from dislocation has little influence on fracture toughness, however, the mode I SIF and EDIF arising from dislocation have great influences on fracture toughness. 相似文献
998.
Shy-Der Lin Shuoh-Jung Liu Han-Chun Lu Hari Mohan Srivastava 《Czechoslovak Mathematical Journal》2013,63(4):969-987
The main object of this paper is to investigate several general families of hyper-geometric polynomials and their associated multiple integral representations. By suitably specializing our main results, the corresponding integral representations are deduced for such familiar classes of hypergeometric polynomials as (for example) the generalized Bedient polynomials of the first and second kinds. Each of the integral representations, which are derived in this paper, may be viewed also as a linearization relationship for the product of two different members of the associated family of hypergeometric polynomials. 相似文献
999.
Xiaopeng Zhao Min Zhang Changchun Liu 《Mathematical Methods in the Applied Sciences》2013,36(2):169-181
This paper is concerned with a fourth‐order parabolic equation in one spatial dimension. On the basis of Leray–Schauder's fixed point theorem, we prove the existence and uniqueness of global weak solutions. Moreover, we also consider the regularity of solution and the existence of global attractor. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
1000.
Xiang-Yao Wu Xiao-Jing Liu Yi-Heng Wu Qing-Cai Wang Yan Wang Li-Xin Chi 《International Journal of Theoretical Physics》2010,49(1):194-200
In this paper, we give the quantum wave equations of single photon when it is in the vacuum and medium. With these wave equations,
we can study light interference and diffraction with the approach of quantum theory, and also can study the quantum property
of photon when it is in a general crystal and photonic crystal. Otherwise, it can be applied in quantum optics and condensed
matter feld. 相似文献