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81.
Xufeng Dong Jinping Ou Xinchun Guan 《Journal of magnetism and magnetic materials》2010,322(22):3648-3652
Magnetostrictive properties have relationship with the applied orientation field during the preparation of giant magnetostrictive composites. To understand the dependence of the optimal orientation field on particle volume fraction, composites with 20%, 30% and 50% particles by volume were fabricated by distributing Terfenol-D particles in an unsaturated polyester resin under various orientation fields. Their magnetostrictive properties were tested without pre-stress at room temperature. The results indicate that as the particle volume fraction increases, the optimal orientation field increases. The main reason for this phenomenon is the packing density for the composites with higher particle volume fraction is larger than that for those with lower particle content. 相似文献
82.
A. El Allati M. El Baz Y. Hassouni A. Kassou Ou Ali F. Saif 《Journal of Russian Laser Research》2011,32(2):177-187
We suggest a model where the influence of an environment on the atom interference is associated with a random phase. The model
consists of sending a two-level state atom through two cavities, both containing a standing wave field in the Bragg regime
and Raman–Nath regime, respectively. In view of this model, we can visualize the loss of interference fringes if the randomness
of the phase increases, and the restoration of the pattern when it decreases, as which-path information. Then, the controllable
random noise acts as a decoherence that would destroy the quantum features. 相似文献
83.
Chunxia Ou 《Nonlinear Analysis: Real World Applications》2009,10(5):2652-2658
In this paper, shunting inhibitory cellular neural networks with continuously distributed delays are considered. Without assuming the global Lipschitz conditions of activation functions, some new sufficient conditions for the existence and exponential stability of the almost periodic solutions are established. 相似文献
84.
Considering for the potential application in tissue engineering, polyaniline (PANi) film was fabricated via a two-step route: a self-assembled monolayer of C6H5NHC3H6Si(OMe)3 was firstly formed on the single-crystal Si substrate; the conducting PANi film was then prepared through electroless surface polymerization of the aniline molecules on the aniline monolayer-bearing silane surface in an acidic aqueous solution. The formation of PANi film on Si surface was confirmed by characterizations of X-ray photoelectron spectroscope (XPS) and specular reflectance Fourier transform infrared (SR-FTIR) spectrum, etc. At last, the proliferation behaviors of PC-12 cells on the PANi film surface were studied by the [3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) colorimetric assays, acridine orange fluorometric staining, and scanning electron microscope (SEM) observation, etc. The results demonstrate that the as-prepared PANi film provides high ability for cell proliferation, exhibiting promising potentials as surface coating to cultivate neuronal cells for applications in the tissue engineering. 相似文献
85.
Advances in wide bandgap SiC for optoelectronics 总被引:1,自引:0,他引:1
Haiyan Ou Yiyu Ou Aikaterini Argyraki Saskia Schimmel Michl Kaiser Peter Wellmann Margareta K. Linnarsson Valdas Jokubavicius Jianwu Sun Rickard Liljedahl Mikael Syväjärvi 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(3):1-16
Silicon carbide (SiC) has played a key role in power electronics thanks to its unique physical properties like wide bandgap, high breakdown field, etc. During the past decade, SiC is also becoming more and more active in optoelectronics thanks to the progress in materials growth and nanofabrication. This paper will review the advances in fluorescent SiC for white light-emitting diodes, covering the poly-crystalline doped SiC source material growth, single crystalline epitaxy growth of fluorescent SiC, and nanofabrication of SiC to enhance the extraction efficiency for fluorescent SiC based white LEDs. 相似文献
86.
87.
Zeng-Qi Ou 《Journal of Mathematical Analysis and Applications》2004,291(1):203-213
An existence theorem of homoclinic solution is obtained for a class of the nonautonomous second order Hamiltonian systems , ∀t∈R, by the minimax methods in the critical point theory, specially, the generalized mountain pass theorem, where L(t) is unnecessary uniformly positively definite for all t∈R, and W(t,x) satisfies the superquadratic condition W(t,x)/|x|2→+∞ as |x|→∞ uniformly in t, and need not satisfy the global Ambrosetti-Rabinowitz condition. 相似文献
88.
核能的和平利用始于20世纪50年代,那时美国、前苏联等工业发达国家在进行核军备竞赛的同时,也竞相发展核电站.1954年,前苏联建成电功率为5千千瓦的试验性原子能电站,为世界上首座核电站;1957年,美国建成电功率为9万千瓦的希平港原型核电站;这些成就证明了利用核能发电的技术可行性.国际上把上述试验性和原型核电机组称为第一代核电机组. 相似文献
89.
It is well known that topology and dynamics are two major aspects to determine the function of a network. We study one of the dynamic properties of a network: trajectory convergence, i.e. how a system converges to its steady state. Using numerical and analytical methods, we show that in a logical-like dynamical model, the occurrence of convergent trajectory in a network depends mainly on the type of the fixed point and the ratio between activation and inhibition links. We analytically proof that this property is induced by the competition between two types of state transition structures in phase space: tree-like transition structure and star-like transition structure. We show that the biological networks, such as the cell cycle network in budding yeast, prefers the tree-like transition structures and suggest that this type of convergence trajectories may be universal. 相似文献
90.
A pair of enantiomers formulated as {Δ-cis-[Ni(en)2OAc][ClO4]} n (Δ-1) and {Λ-cis-[Ni(en)2OAc][ClO4]} n (Λ-1) (en = diaminoethane, OAc? = acetate anion) were obtained when nickel acetate was reacted with diaminoethane and sodium perchlorate in the absence of any chiral source, whereas the reactions of nickel acetate with 1,3-propanediamine and sodium perchlorate only gave a centrosymmetric complex [Ni(1,3-pn)2OAc][ClO4] (2) (1,3-pn = 1,3-propanediamine). Single-crystal X-ray diffraction analyses of all three complexes indicated that the central Ni(II) atoms all have a distorted octahedral coordination geometry, being coordinated by four nitrogen atoms of the diamine ligands, plus two oxygen atoms of OAc?. In complexes Δ-1 and Λ-1, the monomers of {Δ-cis-[Ni(en)2OAc]}+ and {Λ-cis-[Ni(en)2OAc]}+ are connected through intermolecular hydrogen bonds to generate one-dimensional right- and left-handed homochiral helical chains, respectively, while the monomers of [Ni(1,3-pn)2OAc]+ are linked by similar intermolecular hydrogen bonds to form one-dimensional zigzag chains instead of helical chains. The chiral natures of complexes Δ-1 and Λ-1 have been confirmed by circular dichroism spectroscopy. 相似文献