Use of particle reflection in curved crystals to improve beam collimation in a ring accelerator

The staff of the Institute of High-Energy Physics together with researchers from Russian and foreign scientific centers have discovered a new physical phenomenon – reflection of fast charge particles in curved crystals. This article presents the first experimental results using multiple reflections of protons in silicon crystals to increase the beam collimation efficiency in the U-70 accelerator. The experimental data are compared with theoretical models. The technology developed using reflecting crystals can be used to form oppositely propagating beams in accelerators and has prospects for extracting low-emittance beams on ~1 GeV accelerators for electronuclear facilities and in medicine and industry.     

The monolithic multicell: a tool for testing material components in dye‐sensitized solar cells

A multicell is presented as a tool for testing material components in encapsulated dye‐sensitized solar cells. The multicell is based on a four‐layer monolithic cell structure and an industrial process technology. Each multicell plate includes 24 individual well‐encapsulated cells. A sulfur lamp corrected to the solar spectrum has been used to characterize the cells. Efficiencies up to 6·8% at a light‐intensity of 1000 W/m^su2 (up to 7·5% at 250 W/m²) have been obtained with an electrolyte solution based on γ‐butyrolactone. Additionally, a promising long‐term stability at cell efficiencies close to 5% at 1000 W/m² has been obtained with an electrolyte based on glutaronitrile. The reproducibility of the cell performance before and after exposure to accelerated testing has been high. This means that the multicell can be used as an efficient tool for comparative performance and stability tests. Copyright © 2006 John Wiley & Sons, Ltd.     

Coal slurries: Physiochemical properties and processing

The properties of coal slurries are considered in terms of physicochemical mechanics, and ways of intensifying their processing into marketable products are suggested.     

Monitoring and methods of early diagnostics of damage to optical fibers

Problems related to monitoring of branched fiber-optic networks and the technical implementation of an optical fibers testing system are analyzed. Methods of early diagnostics of damage to optical fibers based on the use of the effects of Brillouin scattering and the principles of the technical implementation of a strain measuring instrument are considered.     

Ion-plasma erosion-resistant nanocoatings based on metal carbides and nitrides

The erosion, corrosion, and heat resistance of alloy/ion-plasma nanolayer coating compositions based on TiC and CrC carbides and TiN, CrN, ZrN, and AlN nitrides are studied. The effect of the nanolayer thickness, composition, and structure of the coatings based on the metal nitrides and carbides on the relative erosion resistance of alloy/coating compositions in a gas-abrasive quartz sand flux is studied at a sand grain size of 300–350 μm, abrasive supply rate of 200 g/min, and an angle of flux incidence of 20° (tangential flow) and 70° (near-head-on attack flow). It is shown that high erosion resistance is characteristic of 15–22 μm thick coatings that are produced by assisted deposition and consist of alternating TiN (70 nm) and CrN (70 nm) layers on a VT1-0 titanium alloy or TiC (70 nm) and CrC (70 nm) layers on an EP866 compressor steel.     

Cross section for U233 and U235 fission by neutrons with energies between 3 and 800 Kev

The fission cross sections for fission of U²³³ and U²³⁵ by neutrons with energies between 3 and 800 Kev have been measured. The neutrons were obtained from a van de Graaff generator using the reaction T(p,n)He³. When the neutron energy is varied between 3.4 and 780 Kev the fission cross section drops from 7.5 to 1.9 barns for U²³³ and from 4.8 to 1.05 barns for U²³⁵.This paper is based on the results of work carried out in 1953–1954.