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961.
M.R. Shi F. Xu Ke Yu J.H. Fang X.M. Ji 《Applied Physics A: Materials Science & Processing》2008,90(1):113-117
In2O3 particles with different morphology were controllably synthesized on silicon substrates by thermal evaporation of In grains
at 900 °C. The structure and morphology of the In2O3 particles were evaluated using X-ray diffraction, and scanning and transmission electron microscopies. The evolution in shapes
as the ratio of {100} relative to {111} increases is clearly observed. The photoluminescence spectrum of the obtained In2O3 structures exhibits UV emission centered at about 378 nm and wide-band emission covering the green and orange regions with
three peaks around 525, 572, and 604 nm.
PACS 81.05.Hd; 81.07.Bc; 81.16.-c; 61.46.-w; 81.40.Gh 相似文献
962.
The quantum mechanical phase distribution and the quantum oscillations of population are studied for a cavity field togetherwith
a driven classical field. The atom is sent through the cavity and driven by a classical field. Also the time evolution of
the system including decay is obtained. The graph showing the Rabi oscillations for this system is changed into a bit pattern
from the system without decay. The phase probability function is also affected due to the presence of cavity decay. 相似文献
963.
Aditya M. Vora 《Central European Journal of Physics》2008,6(2):238-252
Ashcroft’s empty core (EMC) model potential is used to study the superconducting state parameters (SSPs) viz. electron-phonon
coupling strength λ, Coulomb pseudopotential μ*, transition temperature T
C
, isotope effect exponent αand effective interaction strength N
O
V of some binary metallic glasses based on the superconducting (S), conditional superconducting (S’) and non-superconducting
(NS) elements of the periodic table. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi
(IU), Farid et al. (F) and Sarkar et al. (S) are used for the first time with EMC potential in the present investigation to study the screening influence on the aforesaid
properties. The T
C
obtained from the H-local field correction function are in excellent agreement with available theoretical or experimental
data. In the present computation, the use of the pseudo-alloy-atom model (PAA) was proposed and found successful. Present
work results are in qualitative agreement with such earlier reported experimental values which confirm the superconducting
phase in all metallic glasses. A strong dependency of the SSPs of the metallic glasses on the valence ‘Z’ is identified.
相似文献
964.
It is shown how the energy-positivity criterion enables us to localize the energy in various field theories. For this purpose the role of surface integrals in a canonical formalism is investigated. The same techniques are applied to linearized gravity, where the mixed Cauchy-boundary value problem in a finite volume is analyzed. Unconstrained degrees of freedom and boundary data which have to be controlled are found. This paper is part of a program to analyze the possibility of localization of gravitational energy in complete General Relativity. 相似文献
965.
Victor V. Dodonov Margarita A. Man’ko Vladimir I. Man’ko Apostol Vourdas 《Journal of Russian Laser Research》2007,28(5):404-428
A brief review of the history of ten workshops/conferences on “Squeezed States and Uncertainty Relations” and main achievements
in the related fields of quantum physics for the period from 1991 to 2007 are presented. 相似文献
966.
Background
In hippocampal neurons, nuclear calcium signaling is important for learning- and neuronal survival-associated gene expression. However, it is unknown whether calcium signals generated by neuronal activity at the cell membrane and propagated to the soma can unrestrictedly cross the nuclear envelope to invade the nucleus. The nuclear envelope, which allows ion transit via the nuclear pore complex, may represent a barrier for calcium and has been suggested to insulate the nucleus from activity-induced cytoplasmic calcium transients in some cell types. 相似文献967.
Sakari Leino Patrick JC May Paavo Alku Lassi A Liikkanen Hannu Tiitinen 《BMC neuroscience》2007,8(1):78
Background
In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment. 相似文献968.
The wake of a streamwise oscillating cylinder is presently investigated. The Reynolds number investigated is 300, based on
the cylinder diameterd. The cylinder oscillates at an amplitude of 0.5d and a frequencyf
e/fs=1.8, wheref
e is the cylinder oscillating frequency andf
s is the natural vortex shedding frequency of a stationary cylinder. Under these conditions the flow is essentially two dimensional.
A two-dimensional direct numerical simulation (DNS) scheme has been developed to calculate the flow. The DNS results display
a street of binary vortices, each containing two counter-rotating vortical structures, symmetrical about the centerline, which
is in excellent agreement with measurements. The drag and lift on the cylinder have been examined. The time averaged drag
and lift are 1.4 and 0, respectively, which are the same as those on a stationary cylinder at the sameRe. However, the fluctuating drag was high, about 2.68. It has been found that, being symmetrically formed about the centerline,
the binary vortices induce an essentially zero fluctuating lift, which may have a profound implication in flow control and
engineering. 相似文献
969.
Carolyn Ferguson Steven L Hardy David F Werner Stanley M Hileman Timothy M DeLorey Gregg E Homanics 《BMC neuroscience》2007,8(1):85
Background
The β3 subunit of the γ-aminobutyric acid type A receptor (GABAA-R) has been reported to be important for palate formation, anesthetic action, and normal nervous system function. This subunit has also been implicated in the pathogenesis of Angelman syndrome and autism spectrum disorder. To further investigate involvement of this subunit, we previously produced mice with a global knockout of β3. However, developmental abnormalities, compensation, reduced viability, and numerous behavioral abnormalities limited the usefulness of that murine model. To overcome many of these limitations, a mouse line with a conditionally inactivated β3 gene was engineered. 相似文献970.
Grzegorz Stepniak Lukasz Maksymiuk Jerzy Siuzdak 《Optical and Quantum Electronics》2007,39(15):1281-1288
Frequency response of passive optical network (PON) based on multimode fibers is investigated. The network comprises fibers,
connectors and splitters/couplers. It is shown that due to mode filtering at splitters, the frequency response is different
for different network nodes in otherwise symmetrical network. 相似文献