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141.
The activity of metabolism changed in the cultures of Streptococcus diacetilactis, strain Bogdan, with aging. The number of viable cells decreased as well as the ability to evolve oxygen, to produce C-4 compounds, and to react to pH changes by liberating acids upon alkalifying or neutral products upon acidifying. After the culture had been grown during 72 hours, 2,3-butyleneglycol was found in the cultural broth, and the number of viable cells was low. As was revealed by electron microscopy, the cells were intact during 48 hours; they started to disintegrate by 72 hours. After 120 hours all cells were disintegrated. First, the cells produced no more mesosomes, became less electron dense; then the cell wall was decomposed and the contents of the cell poured through disruptions in the cytoplasmic membrane. 相似文献
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L. A. Danilets A. S. Lebedev A. F. Vedishchev L. V. Zysin V. N. Gusev 《Thermal Engineering》2012,59(2):163-170
We present the results of a set of rig tests aimed at elaborating the components of the annular combustion chamber used in
a stationary medium-capacity gas-turbine unit that were obtained during tests of the burner and the segment of a full-scale
annular combustion chamber. The main performance parameters of the combustion chamber’s segment characterizing the range of
its stable operation are determined from aerodynamic and “fire” simulation of the operating modes: temperature state, economic
efficiency, and concentration of harmful emissions. Measures aimed at reducing NOx emissions into the atmosphere are considered. 相似文献
145.
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
146.
Bulanin V. V. Gusev V. K. Kurskiev G. S. Minaev V. B. Patrov M. I. Petrov A. V. Petrov Yu. V. Yashin A. Yu. 《Technical Physics Letters》2019,45(11):1107-1110
Technical Physics Letters - The results of a study of toroidal Alfvén modes using the multifrequency method of Doppler backscattering at the Globus-M tokamak have been presented. The method... 相似文献
147.
Degtyarev M. A. Shapoval A. V. Gusev V. V. Avramov K. V. Sirenko V. N. 《Strength of Materials》2019,51(2):223-230
Strength of Materials - A new approach to optimizing the waffle shell sections of the launch vehicle is proposed. The waffle cantilever cylindrical shells are considered under the action of the... 相似文献
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