Investigation of clustering in light nuclei by means of relativistic-multifragmentation processes

New results concerning the topology of the fragmentation of relativistic nuclei ⁷Li and ¹⁰B are presented. A program is proposed for studying the cluster structure of stable and radioactive nuclei. The use of emulsions in the investigation of nuclear clustering in the fragmentation of light nuclei at energies are in excess of 1 GeV per nucleon is discussed.     

Alkali metal salts of acrylamide C3H4NOM (M = Li,Na, and K): Synthesis and vibrational spectra

Alkali metal salts of acrylamide C₃H₄NOM (M = Li, Na, and K) were synthesized for the first time by metallation of acrylamide with alkali metals, their alkyl derivatives, or hydrides. The structures of the compounds synthesized were studied by Raman and IR spectroscopy. Based on the results obtained, an ionic structure was proposed for the salts. The salts were tested as initiators of the anionic polymerization of acrylamide. The catalytic activity of C₃H₄NOM in the polymerization of acrylamide is not lower than that of the well known catalyst, KOBu¹.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2316–2319, September, 1996.     

Combined Dynamic Model for the Kinetics of Electron Transfer from Cytochrome to a Bacteriochlorophill Dimer in Reaction Centers of Rps. Sulfoviridis

The electron transfer from the heme of cytochrome c to the bacteriochlorophill dimer in reaction centers of photosynthetic purple bacteria Rps. sulfoviridis is studied by laser flash photolysis at 40–296 K in conditions where one, two, or three cytochrome hemes are chemically reduced. In the model used for the electron transfer kinetics, the protein relaxation is described with a temperature-independent oscillatory coordinate and a temperature-dependent diffusion coordinate, with the protein dielectric relaxation times widely distributed along the diffusion coordinate. It is found that all the protein complexes can be divided into proteins with fast (k _et = 10⁷ to 10^–4 s^–1) and slow (k _et 100 s^–1) electron transfer. These populations presumably differ by the protonation state of the functional group. The contribution of the oscillatory and diffusion coordinates alters, which severely affects k _et. Parameters V _ab, G, , ₀, and for these reactions are determined.     

Vibrational spectra and structure of caprolactamates of group II metals

Differences between the IR and Raman spectra of the dicaprolactamates of Mg, Ca, and Ba indicate differences in their structures. Barium dicaprolactamate has an ionic structure, while the dicaprolactamates of Mg and Ca are partially covalent and have one-dimensional chain structures with various types of NCO group (terminal, bridge). In solution the dicaprolactamates of Mg and Ca are associated on account of the formation of bridged NCO groups. It was shown that the vibration frequencies of the bridged NCO groups lie in the range 1580–1620 cm^–1, and those of the terminal groups in the range 1550–1580 cm^–1.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1570–1573, July, 1990.     

Response of tunnel schottky-barrier junctions to radiation pressure of fir laser radiation

The response of tunnel Schottky junctions due to plasma reflection of laser radiation has been investigated in the far infrared. The signal was found to be independent of the laser radiation frequency below the plasma edge. At high power levels a nonlinearity of the response was observed. It is assumed that this nonlinearity is caused by near-zone field effects which lead also to a substantial enhancement of the responsivity.On leave from A. F. Ioffe Physico-Technical Institute of the Russian Academy of Sciences St. Petersburg 194021, Russia     

Oscillations on tunneling conductance of schoitky-barrier n-GaAs/Au junctions

Abstract

Summary A new type of oscilations on tunneling conductance versus applied bias with a characteristic scale of > 40 mV and magnitude ～ 1 p.c. has been observed at 77 K for Au/GaAs:Te junction. The oscillations were enhanced by lighting with the GaP LED and conserved for a long time after switching the LED off. The proposed model explains the observed impurity oscillations by spatial modulations of the Schottky barrier with the impurity substitution and associates the pressure influence on the 0s cillations with changes in band structure of GaAs and with capture of ele ctrons by DX-centers.     

Synthesis of 2-Methoxy-3-pentene in a Liquid Phase over a Sulfoionite Catalyst: II. Kinetic Model of Reactions Occurring in the Synthesis

The kinetics of 2-methoxy-3-pentene synthesis from 1,3-pentadiene isomers and methanol was considered. Reaction rates were measured experimentally, and the compositions of reaction mixtures were determined by chromatography. Reaction rate constants and the activation energy of the main reaction were determined experimentally.     

Sign inversion for the velocity of light — A new discrete symmetry transform in electrodynamics

The invariance of the electrodynamic equations with respect to change in sign of the velocity of light is shown. Some physical consequences of this symmetry are considered.I. V. Kurchatov Institute of Atomic Energy. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 69–72, December, 1992.