[en] A Radioisotope probe for determining the filtration direction and rates of underground waters by the single well method has been proposed. The probe containes a radiation receiver in the form of detectors connected in parallel and equispaced along the outer probe circumference, a centered injector having a unique feature in that, in order to increase the probe resolution, each detector is provided on the injector side with a streamlined protecting shield made of material opaque for the given kind of nuclear radiation. To provide for delayed radioactive indicator additon into a well, the injector having a bore for indicators enclosed in a water-soluble shell, is made of a porous material. Instrument design and operation have been described. The radioisotope probe may find applications in hydrogeologic, engineering-geologic, and water management research for simultaneous determination of underground water filtration direction and rate

No abstract available

No abstract available

No abstract available

No abstract available

No abstract available

[en] A neutron-activation method of determining microquantities of Br in mine water, drinking water and ground water is described. The pH of the water sample (50-100 ml) is adjusted to 7-8, the sample evaporated till dry and the residue (25-200 mg) wrapped in Al foil; this is sealed, together with a NH₄Br standard (1x10^-6 g Br), in a quartz ampoule and the ampoule placed in a Cd container with a wall thickness of 1 mm; the container is irradiated for 7-10 hr in a neutron flux of 1.8x10¹³ n/cm²sec and retained subsequently for 5-8 days to allow the interfering ²⁴Na to decay. The sample and standard are then removed from the ampoule and the ⁸²Br activity (half life=35.35 hr) measured for 10-30 min from the 0.554 and 0.78 MeV γ peaks on an integrating γ,γ coincidence spectrometer. The sensitivity of the Br determination is 1x10^-6 g, the mean square error 5-20%. The method is recommended for large-scale analyses of petroleum waters. (author)

[en] Simple accelerated high-sensitive neutron activation methods have been developed for determining the content of mercury in small volumes of aqueous samples without their previous concentration. The analysis is carried out by means of extraction and chromatography. The radiochemical purity of the fractions separated is checked by gamma spectra. It has been shown that within the range of high concentrations of mercury the most intense spectral peaks ¹⁹⁷Hg, sup(197m)Hg, ²⁰³Hg at gamma-quanta energies equal to 77, 69.134, 72.249 keV, respectively have been revealed. The sensitivity of determining Hg by means of the 77 keV peak amounts to about 1.5x10^-10 g/ml

[en] The Czochralski method has been applied to prepare the crystals of lithium metavanadate 10 mm diameter and 40 mm in long. Reflection and transmission spectra are measured on the oriented LiVO₃ samples in the range of wave length from 0.2 to 3 μm. The measurements are used to investigate the edge of LiVO₃ crystal absorption with various directions of the vector of polarization of the falling light

[en] An analytical method was verified using ores from various parts of the Kuruksai Pb-Zn deposit in the Tajik SSR. Samples of the waters to be analysed (Volume 0.4-0.6 litre) were concentrated by evaporation to dryness and packed in Al foil. The weighed amounts (300-700 mg) prepared in this way - together with Sc, Co, Se and Sc standard samples weighing 5x10^-8 g, 2.4x10^-5 g, 5x10^-6 g and 2x10^-6 g respectively - were irradiated in a thermal neutron flux (1.8x10¹³ neutrons/cm².s) for 20 days and then held for 1O-15 days to permit the decay of ²⁴Na, ⁴²K and other comparatively short-lived radioisotopes such as ²⁷Mg, ²⁸Al, ³⁸Cl and ⁴⁹Ca. Radioisotopes such as ⁴⁶Sc, ⁵¹Cr, ⁵⁹Fe, ⁶⁰Co, ⁶⁵Zn, ⁷⁵Sc, ⁸⁵Sr, sup(110m)Ag, ¹¹⁴In, ¹²⁴Sb and ¹³⁴Sc remained in the samples. The partial gamma emission intensities of the ⁴⁶Sc, ⁶⁰Co, ⁷⁵Se, sup(110m)Ag and ¹²⁴Sb were determined using a total-coincidence spectrometer, with which one can measure the activities of these radioisotopes on the basis of their cascade gamma emission. Thus, by measuring the ⁴⁶Sc, ⁶⁰Co, ⁷⁵Sc, sup(110m)Ag and ¹²⁴Sb activities in the samples and standards, with subsequent comparison of the results, it was possible to determine their concentrations in the samples. In some water samples it was not possible to measure the sup(110m)Ag partial activity against the background of ⁶⁰Co, ¹²⁴Sb and ⁴⁶Sc owing to the low Ag concentration. In such cases a radio-chemical separation method was used. The sensitivities of the Sc, Co, Se, Ag and Sb determinations were 5x10^-8 g, 1x10^-6 g, 6x10^-6 g and 1.5x10^-6 g respectively. (author)