Investigation of the processes of obtaining plastic treatment and electrochemical behaviour of lead alloys in their capacity as anodes during the electroextraction of zinc II. Electrochemical formation of phase layers on binary PbAg and PbCa, and ternary PbAgCa alloys in a sulphuric-acid electrolyte for zinc electroextraction

The electrochemical oxidation processes and phase formation on binary PbAg and PbCa, and ternary PbAgCa alloys during anodic treatment of the electrodes for conditions in a sulphuric acid electrolyte were investigated.The electrochemical behaviour of lead and its alloys was studied by the cyclic voltammetry method (CVA). X-ray and SEM were used for the phase composition and surface structure analysis. It was established that only the ternary plastically treated PbAg 0.5%-Ca 0.11% alloys reveal similarities to the industrially applied PbAg 1 % anodes. It may be assumed in the case of ternary alloys that the catalytic layer is composed of a dense non-conductive MnO₂ layer of crystals serving as basic sites for oxygen evolution.     

Absorption edge and energy gap of anodic oxide films on bismuth

The absorption edge, energy gap and transition type have been determined for anodic films on bismuth, obtained in two types of electrolytes. The first, a glycol borate electrolyte, is representative of electrolytes that form “pure” films, and the other, a phosphate solution, is assumed to incorporate anions into the film. This incorporation was found to decrease the effective energy gap and to change the transition type.     

Transition strengths B(E2) in the yrast bands of doubly even nuclei

Experimental data on absolute E2 transition strengths in the yrast bands of even-even nuclei are summarized in a table. In diagrams, the moments of inertia $\text{J}$(I → I ? 2) and the E2 transition moments Q₀(I → I ? 2) derived for each nucleus are presented versus (khω)² (ω is the rotational frequency). Data available up to May 1980 have been included.     

Space radiation measurements on-board ISS--the DOSMAP experiment

The experiment 'Dosimetric Mapping' conducted as part of the science program of NASA's Human Research Facility (HRF) between March and August 2001 was designed to measure integrated total absorbed doses (ionising radiation and neutrons), heavy ion fluxes and its energy, mass and linear energy transfer (LET) spectra, time-dependent count rates of charged particles and their corresponding dose rates at different locations inside the US Lab at the International Space Station. Owing to the variety of particles and energies, a dosimetry package consisting of thermoluminescence dosemeter (TLD) chips and nuclear track detectors with and without converters (NTDPs), a silicon dosimetry telescope (DOSTEL), four mobile silicon detector units (MDUs) and a TLD reader unit (PILLE) with 12 TLD bulbs as dosemeters was used. Dose rates of the ionising part of the radiation field measured with TLD bulbs applying the PILLE readout system at different locations varied between 153 and 231 microGy d(-1). The dose rate received by the active devices fits excellent to the TLD measurements and is significantly lower compared with measurements for the Shuttle (STS) to MIR missions. The comparison of the absorbed doses from passive and active devices showed an agreement within +/- 10%. The DOSTEL measurements in the HRF location yielded a mean dose equivalent rate of 535 microSv d(-1). DOSTEL measurements were also obtained during the Solar Particle Event on 15 April 2001.     

Improving the concept of an asynchronous cyclotron

The main results from improving the concept of an asynchronous cyclotron, the latest version of which has been dubbed a variable-phase asynchronous cyclotron, are presented. Its characteristics are considered using the example of a six-cavity scheme. Its advantages are shown for the multistage acceleration of ultra-high-power proton beams with energies of 2–1000 MeV and continuous currents of up to hundreds of milliamperes over ordinary isochronous and superconducting versions of cyclotrons with separated orbits. The problems of the beam halo are also discussed, and easier possibilities of obtaining spherical bunches for reducing the particle losses are shown. The cost of creating such an accelerator is estimated, and the main relationships for the preliminary selection of its calculation parameters are presented.Translated from Pribory i Tekhnika Eksperimenta, No. 1, 2005, pp. 14–23.Original Russian Text Copyright ¢ 2004 by Tumanyan, Sargsyan, Nikogosyan.