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991.
Qing-Quan Jiang Wei Ren Jian Tang Xiao-Feng Liu 《International Journal of Theoretical Physics》2007,46(6):1449-1454
Applying the semi-classical quantum tunneling model, we have studied the Hawking radiation via tunneling from a cylindrically
symmetric black hole. The derived results show that the tunneling rate of at the event horizon of the black hole is related
to Bekenstein–Hawking entropy and the factual radiation spectrum is not strictly pure thermal, but is consistent with the
underlying unitary theory.
PACS numbers: 04.20.-s, 97.60.Lf. 相似文献
992.
We show that the exact energy eigenvalues and eigenfunctions of the Schrödinger equation for charged particles moving in certain class of non-central potentials can be easily calculated analytically in a simple and elegant manner by using Nikiforov and Uvarov (NU) method. We discuss the generalized Coulomb and harmonic oscillator systems. We study the Hartmann Coulomb and the ring-shaped and compound Coulomb plus Aharanov–Bohm potentials as special cases. The results are in exact agreement with other methods. 相似文献
993.
Daniel S. Freed Gregory W. Moore Graeme Segal 《Communications in Mathematical Physics》2007,271(1):247-274
In the ordinary quantum Maxwell theory of a free electromagnetic field, formulated on a curved 3-manifold, we observe that
magnetic and electric fluxes cannot be simultaneously measured. This uncertainty principle reflects torsion: fluxes modulo
torsion can be simultaneously measured. We also develop the Hamilton theory of self-dual fields, noting that they are quantized
by Pontrjagin self-dual cohomology theories and that the quantum Hilbert space is -graded, so typically contains both bosonic and fermionic states. Significantly, these ideas apply to the Ramond-Ramond field
in string theory, showing that its K-theory class cannot be measured. 相似文献
994.
Zhongzhi Zhang Shuigeng Zhou Tao Zou Lichao Chen Jihong Guan 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(2):259-264
We make a mapping from Sierpinski fractals to a new class
of networks, the incompatibility networks, which are scale-free,
small-world, disassortative, and maximal planar graphs. Some
relevant characteristics of the networks such as degree
distribution, clustering coefficient, average path length, and
degree correlations are computed analytically and found to be
peculiarly rich. The method of network representation can be applied
to some real-life systems making it possible to study the complexity
of real networked systems within the framework of complex network
theory. 相似文献
995.
Dubois F Meunier S Rabau G Poisson F Guyader G 《The Journal of the Acoustical Society of America》2011,130(5):EL284-EL289
The detection of multicomponent signals for which the components are not equidetectable is precisely investigated as a function of the level difference ΔL(i∕j) between components. The detection thresholds are determined for a seven-tone complex signal with random starting phases masked by white noise. Level differences between the components are examined. A model for non-equidetectable conditions based on the statistical summation model is described. The improvement in detection is calculated from the level difference between components that is related to the thresholds for single components. The model predictions are in accordance with the experimental results. 相似文献
996.
This paper describes a novel fiber-coupled heterodyne interferometer using a micro-electro-mechanical system (MEMS) mirror
and an f-theta lens. In this interferometer system, the cross-polarized laser beams operating at 2 μm with the frequency difference
of 100 kHz are introduced by means of the two acousto-optic modulators (AOM). The sample with diameter of 300 mm is uniformly
scanned by the 1 mm laser beam with the help of the combined optical scanning configuration, a MEMS mirror and an f-theta
lens. The output intermediate signal from the two channels, reference channel and the measurement channel, are processed in
the 12 bit analog-to-digital (A/D) process system. Details of our interferometer scheme are discussed. 相似文献
997.
The preconcentration of analytes is important in biochemical analysis as it offers the ability to detect for trace species,
and increase signal-to-noise ratios when using optical sensing on fluorophores. A strong advantage of the evaporation technique
lies in its ability to operate without the need of any energy source; albeit major challenges exist on how to increase the
surface area exposure to air for heightened evaporation, ensure no further increases once specified analyte concentrations
have been achieved, and not needing any intervening membranes. We demonstrate here that the droplet creation and retraction
approach in capillary based microplates offers such abilities whilst at the same time facilitating mixing. 相似文献
998.
Bao-Xi Sun Hua-Xing Chen E. Oset 《The European Physical Journal A - Hadrons and Nuclei》2011,47(10):127
The ρρN and ρρΔ three-body systems have been studied within the framework of the fixed center approximation of Faddeev equation. The ρρ interaction in isospin I = 0 , spin S = 2 is strongly attractive, and so are the N ρ, ρΔ interactions. This leads to bound states of both ρρN and ρρΔ. We find peaks of the modulus squared of the scattering matrix around 2227 MeV for ρρN, and 2372 MeV for ρρΔ. Yet, the strength of the peak for the ρρN amplitude is much smaller than for ρρΔ, weakening the case for a ρρN bound state, or a dominant ρρN component. A discussion is made on how these states can be searched for in present programs looking for multimeson final
states in different reactions. 相似文献
999.
Yongming Sun Xianluo Hu Wuxing Zhang Lixia Yuan Yunhui Huang 《Journal of nanoparticle research》2011,13(8):3139-3148
Ag1.8Mn8O16 nanorods have been synthesized on a large scale by a facile hydrothermal route. The effects of experimental conditions including
reaction time and reactant concentration on the phase and morphology of the final products were investigated systematically.
The products were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron
microscopy (TEM), and energy-dispersive X-ray (EDX) spectroscopy. Electrochemical lithium-storage capabilities of the as-formed
nanostructured Ag1.8Mn8O16 were also evaluated. Interestingly, the as-formed Ag1.8Mn8O16 nanorods possess the unique one-dimensional structure and in situ silver loading, which are beneficial features for electrochemical
lithium-storage applications. The results suggest their potential use as cathode materials for lithium-ion batteries. 相似文献
1000.
Li-ion rechargeable batteries based on polymer electrolytes are of great interest for solid state electrochemical devices
nowadays. Many studies have been carried out to improve the ionic conductivity of polymer electrolytes, which include polymer
blending, incorporating plasticizers and filler additives in the electrolyte systems. This paper describes the effects of
incorporating nano-sized MnO2 filler on the ionic conductivity enhancement of a plasticized polymer blend PMMA–PEO–LiClO4–EC electrolyte system. The maximum conductivity achieved is within the range of 10−3 S cm−1 by optimizing the composition of the polymers, salts, plasticizer, and filler. The temperature dependence of the polymer
conductivity obeys the VTF relationship. DSC and XRD studies are carried out to clarify the complex formation between the
polymers, salts, and plasticizer. 相似文献