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331.
V. V. Aleksandrov A. G. Alekseev V. N. Amosov M. M. Basko G. S. Volkov E. V. Grabovskii A. V. Krasil’nikov G. M. Oleinik I. N. Rastyagaev P. V. Sasorov A. A. Samokhin V. P. Smirnov I. N. Frolov 《Plasma Physics Reports》2003,29(12):1034-1040
The features are studied of plasma production in the initial stage of implosion of hollow cylindrical wire arrays at electric-field growth rates of 1012 V/(cm s). The results are presented from the analysis of both UV emission from the wire plasma and the discharge parameters in the initial stage of the formation of a Z-pinch discharge. It is found that, a few nanoseconds after applying voltage to a tungsten wire array, a plasma shell arises on the wire surface and the array becomes a heterogeneous system consisting of metal wire cores and a plasma surrounding each wire (a plasma corona). As a result, the current switches from the wires to the plasma. A further heating and ionization of the wire material are due primarily to heat transfer from the plasma corona. A model describing the primary breakdown along the wires is created with allowance for the presence of low-Z impurities on the wire surface. 相似文献
332.
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334.
I P Serova G A Ole?nikova E V Komarov V M Kondrat'ev G V Fridlianskii 《Antibiotiki i khimioterapii͡a》1989,34(4):258-261
Ageing of oleandomycin preparations was studied. Certain biologically inactive components accumulating on storage of the preparations were isolated and investigated. A scheme for ageing of oleandomycin phosphate preparations is described. The scheme includes cleaving up of the water molecule at C11 and cleaving by the epoxide ring at the early stages and hydrolysis by the glycoside bonds at the later stages. 相似文献
335.
336.
The total amylolytic activity and activity of alkaline phosphatase in the intestine mucosa of larvae and fries of roach, blue
bream, and perch change both during the process of individual development and during the day. Maximal intensities of juvenile
feeding was observed primarily in the morning and evening hours. The pattern of diurnal alkaline phosphatase activity correlates
to a greater extent to intensity of juvenile feeding, in comparison to the pattern of total amylolytic activity. In planktivorous
blue bream, such regularity is more pronounced than in benthivorous roach. The total amylolytic activity in fries of roach,
blue bream and perch correlates to fish type of feeding. 相似文献
337.
V. K. Uteshev T. N. Pashovkin A. N. Sevirov E. V. Mel’nikova D. G. Sadikova V. N. Karnaukhov E. N. Gakhova 《Biophysics》2006,51(3):484-488
The effect of continuous ultrasonic treatment on the development of early embryos of common frog Rana temporaria was studied. Intact embryos at the blastula stage were exposed to ultrasound of various frequencies (0.88 and 2.64 MHz) and intensities (0.05 to 1.0 W/cm2) for various periods (1 to 15 min). The increase in ultrasound intensity to 0.7–1.0 W/cm2 and exposure time to 5–15 min resulted in nearly complete mortality. Development of the embryos exposed to ultrasound of medium intensity (0.2–0.7 W/cm2) for 1–5 min was virtually similar to the control. Treatment at a frequency of 2.64 MHz and intensity of 0.05–0.7 W/cm2 for 1–5 min had no effect on the development of amphibian embryos and their survival rate. The increase in intensity of the ultrasound of this frequency to 1 W/cm2 and the exposure time to 5 min decreased the number of normally developing embryos by 35%. 相似文献
338.
CHAD M. HELLWINCKEL TRISTRAM O. WEST DANIEL G. DE LA TORRE UGARTE ROBERT D. PERLACK 《Global Change Biology Bioenergy》2010,2(5):278-287
An integrated, socioeconomic–biogeophysical model is used to analyze the interactions of cap‐and‐trade legislation and the Renewable Fuels Standard. Five alternative policy scenarios were considered with the purpose of identifying policies that act in a synergistic manner to reduce carbon emissions, increase economic returns to agriculture, and adequately meet ethanol mandates. We conclude that climate and energy policies can best be implemented together by offering carbon offset payments to conservation tillage, herbaceous grasses for biomass, and by constraining crop residue removal for ethanol feedstocks to carbon neutral level. When comparing this scenario to the Baseline scenario, the agricultural sector realizes an economic benefit of US$156 billion by 2030 and emissions are reduced by 135 Tg C‐equivalent (Eq) yr?1. Results also indicate that geographic location of cellulosic feedstocks could shift significantly depending on the final policies implemented in cap and trade legislation. Placement of cellulosic ethanol facilities should consider these possible shifts when determining site location. 相似文献
339.
F. D. HERNANDEZ‐VELAZQUEZ C. E. GALINDO‐SANCHEZ M. I. TAYLOR J. DE LA ROSA‐VELEZ I. M. COTE Y. SCHRAMM D. AURIOLES‐GAMBOA C. RICO 《Molecular ecology resources》2005,5(1):140-142
Nine microsatellite loci were isolated and characterized from California sea lions (Zalophus californianus). In addition, two of five loci tested from harbour seal (Phoca vitulina) produced a single, clear band in Z. californianus, as did one out of five loci from grey seal (Halichoerus grypus) and one out of two loci from elephant seal (Mirounga sp.). No locus tested from South American fur seal (Arctocephalus australis) amplified in Z. californianus. Locus variability was assessed in California sea lions from Los Islotes rookery, Baja California Sur, Mexico. All loci were variable, with allele numbers ranging from three to 12. 相似文献
340.
N. B. Rodionov É. A. Azizov A. G. Alekseev A. M. Belov V. I. Gudkov A. V. Krasil’nikov A. I. Markin V. A. Myslin A. A. Ivanov V. G. Petrov V. P. Rodionova S. M. Sotnikov S. N. Tugarinov 《Plasma Physics Reports》2006,32(2):83-93
Results are presented from investigations of the possibility of heating a hydrogen plasma at the fundamental harmonic of the ion cyclotron frequency in the T-11M tokamak. The fluxes of charge-exchange atoms that escape from the plasma in the radial direction and across the toroidal magnetic field (transverse neutrals) were recorded by a Lakmus neutral particle analyzer. Measurements by the analyzer show that, during an RF pulse, the ion temperature increases by approximately 50–100 eV. Such plasma parameters as the ion temperature, rotation velocity, and isotopic composition were measured by a high-resolution spectrometer. According to the data from high-resolution spectroscopy, the ion temperature increases by approximately 150 eV. Results from numerical simulations of the ion cyclotron resonance heating of a hydrogen plasma in the T-11M tokamak are also given. 相似文献