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541.
A. I. Meshcheryakov I. Yu. Vafin A. E. Morozov A. A. Golikov Yu. I. Nechaev 《Plasma Physics Reports》2008,34(3):203-211
The propagation and damping of waves excited by a poloidal antenna in a hydrogen plasma at the ion cyclotron resonance (ICR) frequency were investigated. The longitudinal wavenumber and damping length of waves excited in the ohmically heated plasma of the L-2M stellarator, the dependence of the damping length of fast magnetosonic waves on the magnetic field strength, and the dependence of the antenna load resistance on the plasma density were measured. It is the first time that such complex measurements were performed in experiments on ICR heating of a hydrogen plasma at the fundamental harmonic of the ion gyrofrequency in toroidal magnetic confinement systems. 相似文献
542.
G. M. Chuiko V. V. Zakonnov A. A. Morozov E. S. Brodskii A. A. Shelepchikov D. B. Feshin 《Inland Water Biology》2010,3(2):193-202
Persistent organic pollutants (POPs) were found in bottom sediments and muscles of a freshwater fish, bream (Abramis brama L.), from the Rybinsk Reservoir. The contents of POPs decreased in the following order: PCBs > DDT > HCH > HCB. The POPs
contents vary within the ranges of 0.14–50.8, 1.8–6.8, 0.64–2.6, and 0.06–0.41 \gmg/kg wet weight for fish and 24.8–425.6,
2.3–27.1, and 0.34–0.83 fug/kg dry weight for bottom sediments (except for HCH), respectively. The highest and lowest POPs
levels were found in the Sheksna and the Mologa reaches of the reservoir, respectively. The differences in the spatial distribution
of POPs in the reservoir relate to the ways that contaminants enter and migrate in the waterbody but not to various compositions
of bottom sediments. The waste waters of the city of Cherepovets are the main local source of POPs in the Sheksna reach of
the reservoir; in the Mologa reach, the contaminants enter with surface runoff and through global transboundary and local
atmospheric transports from the Cherepovets industry. The qualitative composition of POPs evidences their continuing income
to the reservoir. Considering the revealed levels of POPs accumulation and their legislative safe environment levels, it should
be concluded that PCBs represent the highest environmental threat to the reservoir’s ecosystem. 相似文献
543.
A method is proposed to ease the overcoming of the impurity radiation barrier during current drive in tokamaks, as well as
in alternative fusion and plasmochemical systems with ECR plasma heating. The method is based on the fact that the dependence
of the ionization rate on the electron temperature is strongly nonlinear and the dependence of the recombination rate on the
latter is weaker. The result is that, during temperature oscillations, the effective temperature for ionization-recombination
processes is higher than that in a steady state, so the ionization equilibrium is shifted and strongly emitting ions are stripped
more rapidly. Thereby, ECR plasma heating in the initial discharge stage can be made more efficient by modulating the heating
power at a low frequency. The evolution of the electron temperature in a homogeneous hydrogen plasma with a carbon impurity
and in small ISX-scale tokamaks is simulated numerically, as well as the evolution of the electron and ion temperatures and
of the current during discharge startup in the ITER device. Numerical simulations of the effect of modulation of the ECR heating
power on the rate of heating of nitrogen, oxygen, and argon plasmas were also carried out. The assumption of coronal equilibrium
is not used. It is shown that the low-frequency modulation of the heating power can substantially ease the overcoming of the
radiation barrier. 相似文献
544.
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546.
V V Iazvikov S A Morozov A N Nekrasov 《Biulleten' eksperimental'no? biologii i meditsiny》1988,105(6):764-766
Muscle fibers composition was investigated in vastus lateralis muscles of 103 skaters. In the total population of skaters muscle fibers composition was as follows: muscle fibers, type I--in 54 +/- 2%, muscle fibers, type II A--in 35 +/- 1% and muscle fibers, type II B--in 11 +/- 1%. 13 +/- 8% muscle fibers, type I; 1.56 +/- 6% muscle fibers, type II A and 31 +/- 7% muscle fibers, type II B were observed in the muscles of sprinters, while the muscles of long-distance skaters contained 60 +/- 4%, 33 +/- 4% and 7 +/- 2% muscle fibers, respectively. 相似文献
547.
Z I Vishnevskaia V N Morozov V I Lobyshev G S Kachalova I N Serdiuk A A Timchenko 《Biofizika》1990,35(1):43-46
The influence of substitution of the isotopic composition of the medium on the mechanical properties of immobilized crystals and films from bovine pancreatic ribonuclease and hen egg white lysozyme was investigated. The order of magnitude of the observed effects indicates that the contribution of the electrostatic interaction to the observed isotopic effect may be considered inessential. The absence of aggregation in the H2O and D2O medium under experimental conditions is demonstrated by the method of the low angle dispersion of X-rays. The observed effects of D2O on the mechanical behavior of crystals and films of proteins may be accounted for by the strengthening of molecular interactions in the samples. 相似文献
548.
I V Gmoshinski? T Iu Verina V K Mazo I A Morozov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,114(11):532-534
Polyethylene glycol (PEG)-4000 is proposed as a tracer of intestinal macromolecular permeability. The reproducibility of permeability testing with PEG-4000 and the mechanism of its penetration through intestinal mucosa were studied in adult rats. Permeability measurement for PEG-4000 was reproducible when repeated twice for 2 days. This makes it possible to repeat PEG-4000 permeability testing before and after any experimental impact on the intestine. I.p. administration of colchicine to rats (125 micrograms/100 g b. w.) significantly inhibited intestinal absorption of PEG-4000 fed to the animals 3 hours later. Hence, PEG-4000 penetration through the intestinal mucosa is mediated by the system of enterocyte cytoplasmic microtubules. Mucosal permeability for PEG-4000 may be consequently considered as a valuable model of permeability for protein macromolecules. 相似文献
549.
P Shiyanov S Bagchi G Adami J Kokontis N Hay M Arroyo A Morozov P Raychaudhuri 《Molecular and cellular biology》1996,16(3):737-744
550.