Ion-beam etching of ZnS single crystals,characteristic features and application

Ion-beam etching (IBE) was used to look into the possibility of the 100 and 111 planes of ZnS single crystals with a sphalerite structure being polished by etching. The topographic changes occurring during IBE of these planes were analyzed. The IBE rates were determined for the 110 and 111 planes at various powers of the bombarding argon ion beams. Electron diffraction and luminescence analyses were performed to estimate the degree of amorphization of the surface of the single crystals under IBE. The capabilities of IBE for determining the profile of impurity distribution in ion-implanted layers are shown.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 79–83, July, 1979.The authors express their gratitude to L. M. Krasil'nikova for her assistance in the course of the work.     

Method for calculating small-angle neutron scattering spectra using all-atom molecular dynamics trajectories

A method for calculating small-angle neutron scattering (SANS) spectra based on data obtained using the method of the all-atom molecular dynamics of biomacromolecular structures is considered. When interpreting the SANS data, this approach makes it possible to take into account the fact that the structure of biomacromolecules in a solution is not a static object. This method is implemented in the form of a module for the GROMACS software package and will be available in version 4.6 of this popular program package for simulating biomacromolecular-structure dynamics.     

Critical current density in railgun accelerators with composite electrodes

Institute of Hydrodynamics, Russian Academy of Sciences, Novosibirsk 630090. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 36, No. 3, pp. 10–17, May–June, 1995.     

Improving the Efficiency of Single-Sideband Millimeter-Wave Reception by Returning the Signal Converted into Image

We describe the technique, apparatus, and the results of studies of the possibility of millimeter-wave single-sideband reception with minimum loss, associated with conversion into image. The single-sideband noise temperature of the receivers is improved by a factor of 1.4-1.9 in the N and Y bands.     

Synthesis and properties of pyrimidinylalkylsulfonamides 4. Reaction of the Na salt of p-toluenesulfonamide with mono-N-(ω-haloalkyl)uracils

Conclusions The direction of reaction and the composition and yields of products obtained by reaction of the Na salt of p-toluenesulfonamide with N-(-bromoalkyl)uracils depend primarily on the length of the alkyl chain in the latter: When the Na salt of p-toluenesulfonamide reacts with N-(-bromopropyl)-6-methyluracil, the latter undergoes intramolecular cyclization, whereas the Na salt of p-toluenesulfonamide undergoes intermolecular alkylation at the sulfonamide group on reaction with N-(-bromopentyl)-6-methyluracil. In analogous reactions, N-(-bromobutyl)uracils undergo both intramolecular cyclization, followed by opening of the oxazepine ring by nucleophilic reagents, and intermolecular alkylation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2079–2084, September, 1978.