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A nonlinear equation is derived and its analytic solution describing a soliton-like perturbation propagating at velocity close to the speed of light is found. It is shown that the rate at which the amplitude of a soliton excited by a cold electron beam in a magnetized plasma-filled waveguide grows is proportional to (n b/n 0)1/3, as is the linear growth rate of the beam-plasma instability. 相似文献
674.
Bird censuses were taken by routing in the central part of the Prilenskoe plateau, a region poorly explored by ornithologists. The summer population of birds in different habitats at watersheds, in valleys and along riverbanks has been characterized on the basis of the original data obtained. 相似文献
675.
Studies on the bird fauna of the middle Aldan River valley, a poorly explored area of Russia, have been performed to reveal
trends of spatial changes in the group of dominants, faunistic composition, density, species richness, and distribution of
bird assemblages by vegetation layers and to identify environmental factors accounting for these trends. The roles of zonal
and local landscape-ecological conditions in the formation of bird communities have been compared. The status of rare and
endangered species in the study region has been determined. The results are compared with similar data on the lower Maya River
valley. 相似文献
676.
A new water-soluble photochromogenic fluorescent violet pigment with the indicator properties was isolated from the culture fluid of Nocardia fructiferi var. ristomycini, strain 76. By its solubility and mobility in various solvent systems and by the absorption spectrum the new pigment is close but not identical to such a pigment as rubrocyanin. The presence of microelements, i.e. iron and magnesium in the medium was shown to be necessary for production of violet pigment. 相似文献
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It has been found that macroscopic fluctuations of lactatedehydrogenase activity are determined beats: in four series of measurements carried out at different time of the day activity was determined beginning from the 65th minute after defreezing of the enzymic preparation. Practically similar pictures of the variation course with the amplitude about 8% were observed. 相似文献