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[en] We describe the fabrication of a new dosemeter for X and γ radiation based on fluorite for personal dosimetry. (M.W.O.)
[pt]Descreve-se a fabricacao de um novo dosimetro de raios X e γ baseado em fluorita indicado para dosimetria pessoal. (M.W.O.)
[en] The fluorite research and geologic map around the Florencia mining, had carried out by Uruguayan experts. They had used several scientific techniques which allowed obtain important conclusions.
[en] The kinetic parameters of the two high-temperature glow peaks (peaks III and IV) in a fluorite obtained in a region of Nigeria has been determined in detail by using Chen's peak shape and initial rise methods. The values of these parameters calculated with these two methods are comparable. The orders of kinetics of the two peaks are found to be different from either the first or the second. The b values obtained ranged from 1.023 to 1.134 for peak III and from 1.156 to 1.223 for peak IV. The E values ranged from 0.777 to 1.068 eV for peak III and from 1.328 to 1.428 eV for peak IV. The present values of kinetic parameters are compared with those from past studies on fluorite and the observed variations discussed. The electron lifetime in each of these traps, a parameter to dosimetry, was also determined. The value of lifetime obtained for peak III suggests that the peak may be a complex one, when it is viewed in relation to the thermoluminescence enhancement of this peak with storage time that has been reported. The two peaks were tested for quasi-equilibrium (QE) approximation because the general order model used assumed QE condition; it was found that for all the heating rates used peak IV was emitted under QE condition, while peak III was emitted under QE condition only at the smallest heating rates of 7 and 10 degree sign C/s used in this work
[en] Anomalously high concentration of rare and ore elements in mantle rocks of Tyan-Shan and the Pamirs enables us to presume mantle genesis of some deposits of the Republic (B, F, Hg, Sb, Ag, Pb and others). New data on geochemistry of the upper mantle necessitates making changes in the practice and strategy of prognostication-metallogenic works in Tajikistan
[en] The electron resonance method was applied to study fluorites with the aim to found their new typomorphic features and genetic peculiarities. 40 different crystals of the natural fluorite were studied. New types of compensation of the excessive positive charge of the 3+TRsub(2+C) defects are found. Relative contents of different structural types of the 3+TR ligand complexes are studied. Cd3+ centres are investigated more precisely. The measurements were made at 20 deg C using serial radiospectrometer. centres was studied in one sample. The analysis of the data obtained showed that the ratio values of Cd3+ centres of different structural types correlate with the fluorite formation conditions and reflect, in particular, relative activity of the 2+Ca, -F, +Na, 3+TR ions in mineral-forming solution. Their highest values are typical for fluorites, formed from high-temperature hydrothermal solutions, enriched by Na and TR ions at the lowed activity of F and Ca ions and may be considered as one of fluorite typomorphic features
[en] Present article is devoted to geological study of gold deposits in the Republic of Tajikistan. Gold deposits of the Republic of Tajikistan, including Dzhilau, Konchoch, Taror, Chore, Duoba, Pakrut Deposits and others have been studied and categorized.