Low-frequency electromagnetic radiation generated by electron beams in gases

13-MeV electron beams are shown to generate low-frequency electromagnetic radiation in the gaseous medium of a 100-m-long dielectric electron pipe.     

On the features of decameter radio astronomy

We consider some effects of the VHF radio wave propagation in randomly irregular plasma near the Earth. Applications of these effects to main problems of decameter radio astronomy are discussed. In particular, we show that significant measurement errors of about tens to hundreds of percent for the intensity of the VHF radio emission from an extra-terrestrial source may occur due to scattering and focusing/defocusing of the radiation in the ionosphere if VHF radio astronomical facilities operate at middle latitudes. We find that the angular resolution of discrete radio sources observed using radio interferometry and the well-known scintillation methods cannot be better than about a degree due to the effect of the developed ionospheric turbulence. We propose a modified scintillation method based on the spectral analysis of radio emission from discrete sources, which allows the useful high-frequency signal corresponding to diffraction of VHF emission at weak inhomogeneities of interplanetary plasma to be separated against strong, relatively low-frequency fluctuations of the received radiation due to the effect of the developed turbulent structure of the ionosphere. We show that such a method allows the angular resolution of extra-terrestrial radio sources to be improved up to arcsecond level. Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 43, No. 2, pp. 95–105, February 2000.     

Primary structure of the alanine subunit of ricin T from seeds of the Central Asian castor oil plant. V. Peptides obtained by cyanogen bromide cleavage

The cleavage of the carboxymethylated Ala subunit of ricin T by cyanogen bromide has been performed. Four fragments have been isolated in the individual state by gel filtration and high-voltage paper electrophoresis. The sequence of the cyanogen bromide peptides in the protein chain has been established. Partial structures of three cyanogen bromide fragments have been determined.