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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Let M
n
denote the partial maximum of a strictly stationary sequence (X
n
). Suppose that some of the random variables of (X
n
) can be observed and let [(M)\tilde]n\tilde M_n
stand for the maximum of observed random variables from the set {X
1, ..., X
n
}. In this paper, the almost sure limit theorems related to random vector ([(M)\tilde]n\tilde M_n
, M
n
) are considered in terms of i.i.d. case. The related results are also extended to weakly dependent stationary Gaussian sequence as its covariance function satisfies
some regular conditions. 相似文献
993.
XIONG Zi-jun DU Peng LI Bian XU Li-li ZHEN Xue-chu FU Wei .Key Laboratory of Smart Drug Delivery Ministry of Education & PLA 《高等学校化学研究》2011,(4):655-660
The serotonin 2A(5-HT2A) receptor has been implicated in several neurological conditions and potent 5-HT2A antagonists have therapeutic effects in the treatment of schizo phrenia and depression.In this study,a potent novel 5-HT2A inhibitor 05245768 with a Ki value of (593.89±34.10) nmol/L was discovered by integrating a set of computational approaches and experiments(protein structure prediction,pharmacophore-based virtual screening,automated molecular docking and pharmacological bioassay).The 5-HT2A recept... 相似文献
994.
Qiuping Ding Xianjin LiuBanpeng Cao Zhenzhen ZongYiyuan Peng 《Tetrahedron letters》2011,52(16):1964-1967
A CuCl2·H2O-catalyzed tandem reaction of 2-iodophenol with isothiocyanate in water is described, which provides an environmentally benign, efficient, and practical route for the generation of 2-iminobenzo-1,3-oxathiole. It was noteworthy that most of the products were easily separated from the reaction system by simple filtration. 相似文献
995.
A statistical inversion method is proposed for the photon–photoelectron-counting statistics in quantum key distribution experiment. With the statistical viewpoint, this problem is equivalent to the parameter estimation for an infinite binomial mixture model. The coarse-graining idea and Bayesian methods are applied to deal with this ill-posed problem, which is a good simple example to show the successful application of the statistical methods to the inverse problem. Numerical results show the applicability of the proposed strategy. The coarse-graining idea for the infinite mixture models should be general to be used in the future. 相似文献
996.
997.
研究了脉冲HF激光与水柱表面相互作用下电信号的产生过程。电信号显示了与激光能量线性相关的峰值间有时间间隔的两峰结构,且第二个尖峰在水柱底部的蒸汽腔塌缩后出现。实验还显示电信号的幅值和激光脉冲照射过程中是否存在膨胀和挤压的薄水层密切相关。如果在电池上边缘和石英平板(石英板紧邻电池,并与水柱上表面相接)之间存在一薄水层,电信号强度会增加10倍。 相似文献
998.
Within a quantum virial expansion, we investigate theoretically the violation of universal thermodynamics for a strongly interacting unitary Fermi gas trapped in a harmonic potential. The violation is caused by the existence and anisotropy of the trapping potential and a finite-range of the two-body interaction. We calculate the second virial coefficient by solving a two-fermion problem in 3D uniform harmonic traps, as well as in anisotropic traps. In the unitarity limit, the universal value of the trapped second virial coefficient is 1/4. We discuss in detail the non-universal correction to the second virial coefficient and to the equation of state. 相似文献
999.
Deyan Peng Xiangui Chen Yang Wang Zhigao Hu Ke Yu Ziqiang Zhu 《Applied Physics A: Materials Science & Processing》2011,105(2):463-468
The structural and optical properties of the needle-like ZnO nanostructure grown on the carbon nanotubes (ZnO/CNTs) have been
studied by scanning electron microscope (SEM), X-ray diffraction (XRD), and photoluminescence (PL) spectra. It can be seen
that there is about tens of nanometers in diameter of the single ZnO nanorod from the SEM picture. The XRD analysis shows
that the prepared film is of typical wurtzite hexagonal phase without impurity. Temperature dependence of electronic transitions
in the ZnO/CNTs has been investigated by PL in detail. The emission features in near band gap at 10 K reveal a redshift trend
compared to ZnO single crystal, which is associated with the strong interfacial connection between ZnO and CNTs. Moreover,
the intensities of all transitions in near band gap and visible regions decrease with increasing the temperature but increase
with the excitation power. It can be concluded that the combined effect from ZnO and CNTs plays an important role in the PL
response. The emission variations with the temperature for the ZnO/CNTs are the result of the electron–phonon interaction
and the lattice thermal expansion. 相似文献
1000.
Bi-Yu Tang Dong-Lin Li Ping Chen Jian-Xiong Yi Li Wen Li-Ming Peng Wen-Jiang Ding 《Solid State Sciences》2010,12(5):845-850
Ab initio density functional theory (DFT) and density function perturbation theory (DFPT) have been used to investigate the thermal properties of the Al–Mg–Sc, Al–Mg–Zr and Al–Mg–Sc–Zr alloys over a wide range of temperature and pressure. Phonon dispersions are obtained at equilibrium and strained configurations by DFPT. Using the quasiharmonic approximation (QHA) for the free energy, several physical quantities of interest such as thermal Grüneisen parameter, heat capacity at constant pressure and at constant volume, thermal expansion coefficient, entropy, adiabatic bulk modulus and isothermal bulk modulus as a function of temperature and pressure are calculated and discussed. The present results show that the thermal expansion coefficient of the Al–Mg–Sc–Zr is far lower than that of Al–Mg–Sc and Al–Mg–Zr, and the variation features in the adiabatic bulk modulus and isothermal bulk modulus for the Al–Mg–Sc–Zr are also very different from that of Al–Mg–Sc and Al–Mg–Zr. 相似文献