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1.
EB Poluéktova NK Khitrov VI Andreev SG Pak BK Danilkin 《Canadian Metallurgical Quarterly》1997,69(11):14-16
Changes in the activity of acid phosphatase (AP) and its isoenzymes (tartrate-insensitive AP and formalin-insensitive AP) were investigated in patients with food poisoning in the course of the disease. The activity of AP and its isoenzymes in the serum started to grow in early convalescence and reached maximum in late convalescence. Total activity of AP in food toxic infections consists primarily of the activity of its platelet fraction. AP activity may serve as an additional criterion to predict vascular platelet involvement of hemostasis. 相似文献
2.
A. Andreev L. Prahov M. Gabrovska A. Eliyas V. Ivanova 《Applied catalysis. B, Environmental》1996,8(4):365-373
The catalytic activity of a wide range of transition metal oxides in oxidation of sulphide ions by air in aqueous medium was studied. Some specific features of the reaction mechanism on some of the studied oxides were considered. The transition metal oxides are promising catalysts for practical application. Some of these oxides will allow the preparation of catalysts possessing activity comparable to that of the cobalt phthalocyanine based catalysts, popular in industrial practice. 相似文献
3.
4.
A new superfluid specific additive integral of motion is found. This facilitates investigation of the general thermodynamic equilibrium conditions of a superfluid. The analysis is performed in an extended space of thermodynamic variables containing (along with the usual thermodynamic coordinates such as pressure and temperature) superfluid velocity and momentum density. The equilibrium stability conditions lead to thermodynamic inequalities which replace the Landau superfluidity criterion at finite temperatures. 相似文献
5.
V. P. Kuznetsov D. Yu. Remizov V. B. Shmagin K. E. Kudryavtsev V. N. Shabanov S. V. Obolensky O. V. Belova M. V. Kuznetsov A. V. Kornaukhov B. A. Andreev Z. F. Krasil’nik 《Semiconductors》2007,41(11):1312-1314
Results of experimental studies of erbium ion electroluminescence in p ++/n +/n-Si:Er/n ++ silicon diode structures grown by sublimation molecular-beam epitaxy are discussed. The distinctive feature of these structures is that the regions of electron flux formation of (n +-Si) and impact excitation of erbium ions (n-Si:Er) are spaced. The influence of the n +-Si layer thickness on electrical and electroluminescent properties of diodes was studied. It was shown that n +-Si layer thinning causes the transformation of the structure breakdown mechanism from tunneling to avalanche. The dependence of the Er3+ ion electroluminescence on the thickness of the heavily doped n +-Si region is bell-shaped. At the n +-Si-layer doping level n ≈ 2 × 1018 cm?3, the maximum electroluminescence intensity is attained at an n +-Si layer thickness of ~23 nm. 相似文献
6.
A new method for simulation of truncated random variables is described. Several similar methods are considered. It is shown that a substantial reduction in computation time is achieved by utilizing the proposed method.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 12–13, April, 1995. 相似文献
7.
V. G. Shengurov S. P. Svetlov V. Yu. Chalkov B. A. Andreev Z. F. Krasil'nik B. Ya. Ber Yu. N. Drozdov 《Inorganic Materials》2003,39(1):3-5
The Ge and Er depth profiles in Si1 – x
Ge
x
layers grown on Si(100) substrates by Si sublimation-source molecular-beam epitaxy in GeH4 were studied by secondary ion mass spectrometry. The results demonstrate that Ge facilitates Er incorporation into the growing Si–Ge layer. The Er dopant profile becomes sharper with increasing Ge content. The Ge profile also has rather sharp boundaries, indicating that there is no Ge surface segregation, which is attributable to the presence of adsorbed hydrogen, acting as a surfactant. 相似文献
8.
V. V. Andreev A. V. Kedrov B. G. Levakov O. A. Mingazov S. G. Porubov S. V. Shugaev 《Atomic Energy》2007,102(3):174-180
The results of investigations of the operation of the IGRIK pulsed homogeneous solution research complex in the unconventional
(for pulsed reactors) two-pulse mode with successive reactivity increments with generation of prompt-or delayed-neutron pulses
are presented. Experimental data which give an idea of the processes occurring in the reactor core in the two-pulse regime
are obtained. These data made it possible to determine whether or not the IGRIK reactor can be operated in this regime and
the limitations imposed by the physical processes and special design characteristics of the system.
It is shown that are pulses can be generated in several different ways. The dependences of the fission-pulse characteristics
in a given regime on the initial conditions and the methods for obtaining the pulses are investigated. Methods are proposed
for increasing the operational possibilities of the reactor.
__________
Translated from Atomnaya énergiya, Vol. 102, No. 3, pp. 146–151, March, 2007. 相似文献
9.
This article examines the mathematical aspects of a method developed for frequency-time correction of distortions of radiation
patterns recorded in a closed range with partial echo suppression. The efficiency of the method is analyzed with allowance
for the dimensions of the range and the bandwidth of the test antenna.
Translated from Izmeritel'naya Tekhnika, No. 12, pp. 44–46, December, 1996. 相似文献
10.
The paper gives a method of model XLPE medium voltage cable insulation testing for partial discharges and electrical treeing
with a point to plane test geometry. Based on this method, a comparative estimate of insulation resistance to treeing and
partial discharges have been made. XLPE crosslinked by different methods (steam medium and hot nitrogen medium) and with varying
contents of inorganic filler kaolin were tested. The characteristics of partial discharges were measured by means of a pulse
height analyser characterized with a microscope. The data have been analysed statistically. 相似文献