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981.
V. I. Dubovik V. A. Bogdanova N. A. Davletkil’deev N. A. Semikolenova O. A. Shutyak 《Semiconductors》1998,32(1):31-32
The influence of gg irradiation (60Co) of various intensities (P
γ≈1.7−7.5kGR/h) on the photoluminescence of GaAs:Te single crystals [n
0=(1.2–2.3×1018 cm−3] is investigated. Together with the known photoluminescence impurity bands (hν
max≈1.2 eV and/or hν
max≈1.35 eV) and edge band (hν
max≈1.51 eV), new bands are also observed in the spectra at hν
max≈1.3 eV and hν
max≈1.48 eV. The observed effects are attributed to radiation-stimulated ordering of the donor impurity and deep impurity centers.
Fiz. Tekh. Poluprovodn. 32, 38–39 (January 1998) 相似文献
982.
A response to criticism of threshold plates for the study of color vision developed at the Mendeleev All-Russia Research Institute
of Metrology and published in 1994 is presented. The critics base their conclusions on colorimetric testing and the examination
of the plates.
In response to the article by M. V. Danilova and J. D. Mollon [4].
__________
Translated from Izmeritel’naya Tekhnika, No. 1, pp. 37–39, January, 2007. 相似文献
983.
J. Weise Dr.‐Ing. O. Yezerska M. Busse M. Haesche V. Zanetti‐Bueckmann M. Schmitt 《Materialwissenschaft und Werkstofftechnik》2007,38(11):901-906
Micro‐porous syntactic foams were produced by means of integration of glass bubbles into aluminium and zinc matrices. Preforms of glass bubbles were pressure infiltrated with the alloys AlSi9Cu9 ans ZnAl4Cu using squeeze casting. The preforms were sintered thermically without the use of bonding agents. Using the combination of different sintering steps syntactic foams with locally different densities could be produced. The mechanical properties of the foams were tested indicating a high compression strength of the foams and a very good compression energy absorption. Furthermore, corrosion behaviour and behaviour at higher temperatures were investigated. 相似文献
984.
985.
An analytical model for electroluminescence in SrS:Ce AC thin-film electroluminescent display devices is presented. The model incorporates an exact calculation of the electric field and the effect of activator ionization and bulk traps. Activator ionization is needed to explain several features of luminescence behavior in SrS:Ce devices. These features include the second luminescence peak at the trailing edge of the voltage pulse and the time lag between the luminescence and the applied voltage when the applied voltage consists of bipolar trapezoidal pulses and rectangular pulses of low voltage amplitudes. As a mechanism for the ionization of activators, field-assisted tunneling is shown to be more likely than impact ionization by hot electrons. Physical processes are described in terms of rate equations, and field, current, and luminescence waveforms are calculated for one set of device parameters. The calculated and experimental luminescence waveforms agree 相似文献
986.
987.
Fundamental frequency techniques are used to analyze the series-parallel resonant converter under heavy load conditions, both with a continuous, but distorted parallel capacitor voltage waveform, and with a discontinuous capacitor voltage waveform. The analysis is validated with results from an experimental prototype. The application of the technique to the parallel-loaded L-C resonant converter is also considered. 相似文献
988.
Contemporary approaches to the certification of measurement provision software are considered in domestic and overseas publications.
Normative documentation is analyzed and a scheme is proposed for certification that takes account of the features of programs
used for metrological purposes.
__________
Translated from Izmeritel’naya Tekhnika, No. 5, pp. 65–68, May, 2007. 相似文献
989.
We studied the effect of the structural and phase state of surface layers of nitrided VT1-0 titanium on its surface hardening after additional saturation in an active boron-containing atmosphere (900°C, 5 h, 0.1 MPa Ar, a mixture of boron carbide and borax). Additional treatment almost doubles the surface microhardness of the specimens. Surface hardening is a result of both the formation of borides and carbides and the introduction of additional elements into the lattice of titanium nitrides. We established that the formation of a nonstoichiometric nitride with a deficiency of the nonmetallic component prior to additional treatment enables one to reach the maximum effect of surface hardening. 相似文献
990.