Processing of Rare-Earth Elements from Loparite

Distribution of REEs and Th in extraction from chloride solutions with primary carboxylic acids C₇-C₉, 2-ethylhexanoic acid, and a crude mixture of higher branched carboxylic acids was studied. Thorium can be separated by extraction with carboxylic acids. The decay products were recommended to be precipitated after extraction of REEs. The radioactivity of loparite processing products considerably decreases with time.__________Translated from Radiokhimiya, Vol. 47, No. 1, 2005, pp. 77–79.Original Russian Text Copyright © 2005 by Lebedev, Rudenko.     

Microwave-Frequency Modulation of the Gasdynamic Parameters of Plasma by Laser Radiation

Numerical and asymptotic calculations are performed of the gasdynamic parameters of laser-induced plasma under the effect of high-power laser radiation with microwave-frequency modulation of its intensity. The results of these calculations are compared for the amplitudes of oscillation of these parameters. It is demonstrated that the values of the parameters may be found using the averaging method and represented in the form of the sum of two parts, of which one part is the solution in the absence of modulation, and the other part describes small-scale oscillations about this solution.     

Detection of signals at the output of gravity resonance antennas by estimation of the distribution parameters

The statistical problem of detection of a useful vector signal at the output of resonance spatially-separated gravitational antennas with overlapping directional patterns is considered. A method involving estimation of the distribution parameters of the additive noise at the output of an optimal linear system of whitewashing and matched filters is used to solve the problem. The additive noise is assumed to be a mixture of correlated Gaussian noise and rare random pseudo-gravitational signals (minimax detection criterion).     

The effect of Sn impurity on the optical and structural properties of thin silicon films

The effect of tin impurity on the structure and optical properties of thin-film amorphous silicon is investigated. It is established that tin impurity accelerates crystallization of amorphous silicon. Immediately after deposition of a film onto a substrate at a temperature of ∼300°C, there is a crystalline phase of silicon in samples with tin. High-vacuum annealing at 350–750°C leads to growth of the crystalline phase in films with tin: nanocrystals grow in size from ∼3.0 to 4.5 nm. At the same time, in films without tin, only the degree of the short-range order increases. Silicon film without tin remains amorphous over the entire range of annealing temperatures.     

Semipermeable dynamic membranes for ultrafiltration treatment of ground waters to remove radionuclides

The applicability of semipermeable dynamic membranes based on iron hydroxides and polyvinyl alcohol for ultrafiltration treatment of ground waters to remove radionuclides was studied. The retention of multiple-charged uranium ions and strontium is the most efficient, and that of cesium ion, the least efficient.     

New data on the etiological factors in acute pyelonephritis

Spectrum of microbe agents of acute pyelonephritis has been studied. It is shown that Mycoplasma hominis plays an important role in etiology of acute pyelonephritis besides the already known enterobacteria and Gram-positive cocci. It is also established that mycoplasmal pyelonephritis more often develops in patients with the diseases of urinary blade (cystitis) and genital organs. Results of serological investigations which confirm etiological role of isolated microorganisms in the initiation of acute pyelonephritis are presented.     

Compaction of soils prone to slump-type settlement by an ultraheavy tamper during construction of a hospital complex

Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 1, pp. 2–4, January–February, 1991.