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171.
172.
We study the methodology of measuring quasistatic perturbations of geophysical nature in laser gravitational-wave interferometers. We calculate the transfer function of such an instrument in the destructive interference mode (the “dark spot” mode) taking into account the natural asymmetry of the optical Fabry-Perot cavity lengths in its arms. Formulas have been obtained for estimating the output signal power modulation at the frequency of photon circulation in the arms due to geophysical perturbations. The estimates are compared with the results of observations at the LIGO interferometer. 相似文献
173.
174.
Dependences of the magnetic-field strength of flaws on a electromagnet’s current and the magnetic induction in a magnetic-circuit gap are obtained. The magnetic-field strength of flaws in magnetically hard steels is found to be higher than that of flaws in magnetically soft steels. The results obtained are explained in terms of the demagnetizing action of a surface magnetic dipole as well as the dependence of the magnetic-flux distribution over specimens on the magnetic permeability of a material and on the induction under the electromagnet’s poles. 相似文献
175.
The traditional silver nitrate impregnation method used for visualization of cell borders does not allow the study of intercellular relationships and fails to demonstrate features of cell microrelief. It is shown that osmium tetroxide impregnation of vascular tissue, emphasizing cell border lines, and a special image analysis program for the semiautomatic system IBAS 2 can be used together for the effective analysis of the fine structure and of the cell layer. Our investigations of the aortic endothelium using this complex method have confirmed the heterogeneity of aortic endothelial cells in health and demonstrated that the endothelium of different aortic regions displays differential responses to blood pressure elevation and, further, that a major factor underlying the alterations observed in endothelial cells in disease and hypertension is the differential degree of overlap of the neighboring endothelial cells. 相似文献
176.
The effect of the oxygen content (\(C_{O_2 } \)) in the gas mixture (20% of SiH4 + 80% of Ar) + O2 and the surface area of an erbium target (SEr) on the composition and Er3+ photoluminescence of amorphous a-SiOx:(H, Er, O) films prepared by dc magnetron sputtering has been investigated. Analysis of the experimental data shows that [Er-O] and [Er-O-Si-O] clusters are formed in the gas plasma due to the competing processes of oxidation and sputtering of Si and Er targets and to the interaction of [Si-O] and [Er-O] clusters with each other and with the oxygen in the gas phase. The discontinuities in the dependences of the contents of erbium-bound oxygen and erbium in a film, and N O Er-O and NEr = f(\(C_{O_2 } \), SEr), at \(C_{O_2 } \) ≈ (5–6.5) mol % supports the hypothesis on the existence of different erbium clusters. The necessary conditions for preparing a-SiOx:(H, Er, O) films with the highest photoluminescence intensity of erbium ions at a wavelength of 1.54 μm are determined. 相似文献
177.
The effect of oxygen on the intensity of erbium photoluminescence at λ=1.54 μm in amorphous a-SiOx:H(Er) films formed by dc magnetron sputtering was studied. The oxygen content in the gaseous phase ranged from 0.1 to 12
mol %, with other parameters of deposition remaining constant. Analysis of an a-Si:(H, Er, O) system showed that the range of homogeneity of amorphous a-SiOx:H(Er) is retrograde (T=const). The range of homogeneity can be conventionally divided into two portions, each of which should contain either of
two differently charged [Er-O]
n− and [Er-O-Si-O]
m− clusters (m>n). This inference is confirmed experimentally: in the range of oxygen concentrations amounting to 5.5–8 mol % in the plasma,
unusual associative processes take place probably directly above the growing film surface; these processes are caused by the
appearance of [Er-O-Si-O]
m− clusters in the plasma and at the surface. It is these processes that account for the intensification of erbium photoluminescence
as the oxygen content increases above 5.5 mol %.
__________
Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 37, No. 7, 2003, pp. 853–859.
Original Russian Text Copyright ? 2003 by Undalov, Terukov, Gusev, Kudoyarova. 相似文献
178.
Smagina Zh. V. Novikov A. V. Stepikhova M. V. Zinovyev V. A. Rodyakina E. E. Nenashev A. V. Sergeev S. M. Peretokin A. V. Kuchinskaya P. A. Shaleev M. V. Gusev S. A. Dvurechenskii A. V. 《Semiconductors》2020,54(8):853-859
Semiconductors - The luminescence properties of arrays of spatially ordered self-assembled solitary Ge(Si) nanoislands and their groups, including those embedded in two-dimensional photonic... 相似文献
179.
The optical transmittance of nanostructured cubic PbS (lead sulfide) films with a D03 structure is measured in the wavelength range 300 to 3200 nm. The film thicknesses are in the range ∼120 to ∼400 nm. Electron
microscopy of the microstructure shows that about half of the films’ particles are 60 nm or smaller in size. As the average
particle size is decreased, the band gap E
g
increases from 0.85 to 1.5 eV, being noticeably larger than the band gap of coarse-grained PbS, 0.41 eV. This is indicative
of a blue shift of the optical absorption band in nanostructured PbS films. 相似文献
180.
P. G. Baranov B. Ya. Ber O. N. Godisov I. V. Il’in A. N. Ionov A. K. Kaliteevskiĭ M. A. Kaliteevskiĭ I. M. Lazebnik A. Yu. Safronov H. -J. Pohl H. Riemann N. V. Abrosimov P. S. Kop’ev A. D. Bulanov A. V. Gusev 《Semiconductors》2006,40(8):901-910
Electron spin resonance (ESR) is used to study the neutron transmutation doping of silicon crystals enriched with 30Si isotope: phosphorus donors and radiation defects produced in the course of transmutational doping are observed. The ESR signals related to the phosphorus uncontrolled impurity in 30Si before transmutational doping (the P concentration is ~1015 cm?3) and phosphorus introduced by neutron irradiation with doses ~1 × 1019 cm?2 and ~1 × 1020 cm?2 (the P concentrations are ~5 × 1016 and ~7 × 1017 cm?3, respectively) are studied. As a result of drastic narrowing of the phosphorus ESR lines in 30Si, the intensity of lines increased appreciably, which made it possible to measure the phosphorus concentration in the samples with a small volume (down to 10?6 mm?3). The methods for determining the concentration of P donors from hyperfine structure in the ESR spectra of isolated P atoms, exchange-related pairs, and clusters that consist of three, four, and more P donors are developed. In the region of high concentrations of P donors, in which case the hyperfine structure disappears, the concentration of P donors was estimated from the exchange-narrowed ESR line. 相似文献