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31.
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
32.
Highly Sensitive Pulsed Digital Holography for Built-in Defect Analysis with a Laser Excitation 总被引:7,自引:0,他引:7
A highly sensitive method is presented for noninvasive defect analysis on thin structures with a Q-switched double-pulsed ruby laser with frequency doubling (347 nm). In our research we feature an all-optical arrangement, where a focused laser pulse derived from the same ruby laser (694 nm) acts as a built-in synchronous excitation source for digital holographic interferometry. The recordings are made with a CCD camera for capturing two holograms (two states of the specimen) corresponding to the two UV laser pulses with a short time separation (10-50 mus). Subtraction of the phase distribution in two digital holograms gives a fringe phase map that shows the change in deformation of the specimen between the recordings. The advantage of the proposed method is two fold. First, the use of a shorter wavelength results in a higher sensitivity. Second, owing to the induced synchronous built-in optical excitation, the specimen is not subjected to any external physical excitation devices. Experimental results are presented on identification and evaluation of defects in thin metal sheets. 相似文献
33.
I. G. Rodionova E. T. Shapovalov M. E. Kovalevskaya O. N. Baklanova D. A. Burko N. I. Endel' Yu. B. Gusev R. E. Gliner A. M. Lamukhin V. V. Kuznetsov V. L. Chernousov S. D. Zinchenko S. V. Efimov M. V. Shurygina A. D. Gorin 《Metallurgist》2005,49(7-8):314-323
A method involving alternating immersion in a 3.5% NaCl solution has been developed for corrosion tests of automobile sheet.
Results obtained from 30 cycles of tests (10 + 50 min) of specimens of steels 08Yu, 08ps, 08YuP, 08YuDP, 08GSYuT, and IF established
the dependence of the steel's unit weight gain from corrosion products on its combined content of carbon and silicon: steels
with a lower content of these elements show a smaller gain in weight, i.e., they exhibit greater corrosion resistance. Steel
alloyed with copper (0.23–0.34%) and phosphorus (0.06–0.08%) – the production of which has been mastered by the company Severstal'
— has the highest resistance to corrosion. Use of the method makes it possible to rank grades of automobile sheet in one of
three corrosion-resistance classifications in relation to their chemical composition and the parameters of the production
process.
__________
Translated from Metallurg, No. 8, pp. 46–52, August, 2005. 相似文献
34.
M. S. Avilov A. V. Akimov A. V. Antoshin P. A. Bak Yu. M. Boimel'shtein D. Yu. Bolkhovityanov R. Kh. Galimov R. G. Gromov K. V. Gubin S. M. Gurov E. A. Gusev N. S. Dikanskii I. V. Kazarezov S. N. Klyushchev V. I. Kokoulin E. S. Konstantinov A. A. Korepanov N. Kh. Kot R. M. Lapik N. N. Lebedev A. I. Lobas P. V. Logachev P. V. Martyshkin L. A. Mironenko V. M. Pavlov I. L. Pivovarov O. V. Pirogov V. V. Podlevskikh S. L. Samoilov Yu. I. Semenov B. A. Skarbo A. A. Starostenko O. Yu. Tokarev A. R. Frolov V. D. Khambikov A. S. Tsyganov A. G. Chupyra S. V. Shiyankov 《Atomic Energy》2003,94(1):50-55
The VÉPP-5 injection complex under construction at the Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences is a powerful source of intense electron and positron bunches at 510 MeV, which covers all needs of the electron–positron colliding beam setups currently operating and under construction at the Institute of Nuclear Physics. The complex includes a 285 MeV linear electron accelerator, a 510 MeV linear positron accelerator, and an accumulator–cooler with beam injection and ejection channels. Intense work on the design, assembly, and tuning of the linear electron accelerator has been conducted in the last 2 yr. As a result, by August 2002 the linear electron accelerator was put into operation with all standard subsystems. By this time, the isochronous achromatic turning of the electron beam, a system for converting electrons into positrons, and the first accelerating structure of the linear positron accelerator were assembled and put into operation. All this made it possible to accelerate the positron beam up to 75 MeV. Preliminary results of tests of the linear accelerators are presented. 相似文献
35.
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
36.
37.
38.
Two conflicting problems are solved in the course of chemical decontamination of the primary circuit of nuclear reactors: removing the maximal amount of radionuclides from the surfaces of the primary circuit equipment and minimizing the impact of decontaminating solutions on structural materials. A criterion for reliable determination of the completion of dissolution of surface corrosion deposits is suggested and substantiated. Since the criterion suggested is not related to the specific decontamination solutions, it can be applied to any decontamination procedure and chemical washing of the equipment in nuclear and thermal power industry. 相似文献
39.
S. I. Gusev V. N. Karpov A. N. Kiselev V. I. Kochkin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2009,43(5):324-332
The results of systems tests of the 500 kV busbar magnetization-controllable shunting reactor (CSR), set up in the Tavricheskaya
substation, including measurements of the quality of the electric power, the harmonic composition of the network currents
of the reactor for different values of the reactive power consumed, the determination of the regulating characteristics of
the reactor, the speed of response of the shunting reactor in the current and voltage stabilization modes, and also the operation
of the reactor under dynamic conditions for different perturbations, are presented. The results obtained are analyzed. 相似文献
40.
Yu. M. Milekhin D. N. Sadovnichii S. A. Malinin V. K. Ivanchenko V. L. Klochikhin S. A. Gusev 《Fibre Chemistry》2009,41(1):56-59
The elevated radiation resistance of a microplastic based on Rusar fibres even in combined exposure to ionizing radiation
and mechanical loading was demonstrated. This is probably due to the high degree of orientation of the polymer fibres, so
that radiation chemical decomposition reactions are suppressed and the purely thermal effect of the radiation is experimentally
recorded.
Translated from Khimicheskie Volokna, No. 1, pp. 47-49, January-February, 2009. 相似文献