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991.
L.B.Magalas 《物理学进展》2006,26(3):258-276
本文广泛地收集了有关内耗,力学谱,超声衰减方面的专著及会议文集。反映了20世纪在此领域的英文,俄文出版的书籍。也列出了历次国际会议及前苏联,乌克兰,中国的国内会议。文中包括了点缺陷,电,声子,位错,晶界,电畴等诸方面在内的内耗与力学谱工作。 相似文献
992.
Theoretical investigations and the results of computer modeling of the optical, thermophysical, and thermochemical processes during laser interaction with ocular tissues are reviewed in this paper. Physical-mathematical models and results of numerical simulation of the processes are presented. The computer modeling was applied for investigations of laser heating and coagulation of ocular tissues for treatment of retina diseases and intraocular tumors, cyclophotocoagulation of the ciliary body for treatment of glaucoma, and laser thermal keratoplasty of the cornea. The influence of radiation parameters on the selectivity of laser coagulation of laminated ocular tissues is considered. The results obtained are of essential interest for laser applications in ophthalmology and can be used for investigation of heating and coagulation of tissues in different fields of laser medicine. 相似文献
993.
We study experimentally the frequency dependences of the refractive index n and the absorption coefficient k of distilled,
sea, and river water. The measurements were performed using a quasioptical device with a backward-wave oscillator as the radiation
source and OAP-7 optical-acoustic receivers at a water temperature of 27°C in the cell. The quantities n and k were determined
from the measured transmission and reflection coefficients of the cell with water by means of joint numerical solution of
the equations for these quantities. For distilled water in the frequency range f = 75–120 GHz, we obtained n = 6.142–3.926
· 10–2f[GHz] + 1.307 · 10–4(f[GHz])2 and k = 3.607–2.101 · 10−2 f[GHz] + 5.252 · 10–5(f[GHz])2. On the whole, these data are in good agreement with the measurement results obtained by other authors at several frequencies
of the indicated range and coincide with the calculation data based on the models by Meissner and Wentz and by Liebe et al.
within the limits of the rms determination errors 0.05 and 0.02 for the parameters n and k, respectively. The values of n
and k for different seawater samples and river water containing insoluble admixtures coincide with the values of these quantities
for distilled water within the limits of the experimental measurement errors 3–5% and 1–2%, respectively. The dependences
n(f) and k(f) obtained experimentally for seawater are compared with those calculated on the basis of the developed models.
Measurements of the transmission spectrum of a cell with double distilled water were performed for low power density of radiation
(less than μW/cm2) to reproduce the effect of water resonant transparency reported many times in the literature. Our measurements did not reveal
any resonant features in the spectral behavior of the refractive index n and the absorption coefficient k of water and gave
the same result as for a power density exceeding the threshold of appearance of this effect.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 6, pp. 489–501, June 2006. 相似文献
994.
E. N. Abdullin N. G. Ivanov B. M. Kovalchuk I. N. Konovalov V. F. Losev A. N. Panchenko Yu. N. Panchenko V. S. Skakun V. F. Tarasenko A. G. Yastremsky 《Laser Physics》2006,16(1):104-115
Two-high power excimer laser systems with square (25 × 25 cm) and circular (with a diameter of 40 cm) cross sections of the
output laser beam are described. The first (second) system consists of four (five) excimer lasers. The experimental results
on the generation of the high-quality high-power laser pulses are presented. Laser beams with a pulse duration of 1–250 ns,
a divergence of 0.01 mrad, a spectral line width of 0.01 cm−1, and a pulse energy of up to 330 J are obtained.
Original Text ? Astro, Ltd., 2006. 相似文献
995.
I. B. Samsonov 《Czechoslovak Journal of Physics》2006,56(10-11):1281-1286
We study the quantum properties of two theories with a non-anticommutative chiral singlet deformation ofN=(1, 1) supersymmetry: the Abelian model of a vector gauge multiplet and the model of a gauge multiplet interacting with a neutral hypermultiplet. Both these models are proved to be not only renormalizable but also finite. 相似文献
996.
J. Jiang B.Y. Jiang C.X. Ren F.M. Zhang T. Feng X. Wang X.H. Liu S.C. Zou 《Applied Surface Science》2006,252(10):3642-3646
Hafnium and platinum were deposited onto molybdenum grids by ion-beam assisted deposition method. Electron-emission characteristics from molybdenum grids with Hf and Pt films, which were contaminated by active electron-emission substances (Ba, BaO) of the cathode, were measured using analogous diode method. The surfaces of grids were analyzed by X-ray diffraction. The results revealed that the reaction between BaO and Hf formed BaHfO3 compound, which greatly reduced the accumulation of BaO on the surface and accordingly decreased grid emission. In contrast, Ba were formed by the decomposition of BaO on the surface of Pt film under high temperature and re-evaporated from its surface, which reduced the active electron-emission substances on the surface of the grid and effectively restrained grid emission. Their mechanisms for grid-emission suppression are discussed and a good method to develop new grid-coating materials is suggested. 相似文献
997.
998.
S.K. Mahapatra B.K. Dandapat 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,102(2):277-292
The current study addresses the mathematical modeling aspects of coupled conductive and radiative heat transfer in the presence of absorbing, emitting and isotropic scattering gray medium within two-dimensional square enclosure. A blended method where the concepts of modified differential approximation employed by combining discrete ordinate method and spherical harmonics method, has been developed for modeling the radiative transport equation. The gray participating medium is bounded by isothermal walls of two-dimensional enclosure which are considered to be opaque, diffuse and gray. The effect of various influencing parameters i.e., radiation-conduction parameter, surface emissivity, single scattering albedo and optical thickness has been illustrated. The adaptability of the present method has also been addressed. 相似文献
999.
In this paper, it is shown that some of the results of torus actions on Poincaré duality spaces, Borel’s dimension formula
and topological splitting principle to local weights, hold if ‘torus’ is replaced by ‘pro-torus’. 相似文献
1000.
Chemical techniques were employed to synthesize CdS nanoparticles embedded in polymer (PEG 300) and sol-gel silica matrices. Systematic growth of particles (radius 3–9 nm) was obtained by adjusting post-deposition annealing temperature and time to examine the dependence of surface-state–related luminescence on particle size. Photoluminescence (PL) peak energy showed a linear dependence with a gentle slope in the weak confinement region and a steep slope in the strong confinement region, the divergence being observed near the excitonic Bohr radius for CdS. The empirical relation proposed for the weak confinement region could be used for estimating chemically prepared CdS nanoparticle size with a high degree of reliability from PL peak energy. 相似文献