Purpose. To study conditions of forming the zones of high metal concentration in metal-containing man-made deposits. To assess the likelihood of metal concentration in the placer core.Methods. Analysis of the conditions determining metal-containing placers formation and of metal losses at mining and processing plants, considering the local terrain. Findings.It is proved that the minerals that are carried away from the separators at mining and processing plants are concentrated in the core, which contains up to 90% of heavy metals.Originality. The studies have determined the main factors and regularities governing the distribution of heavy metals in technogenic placers, which help identify their location and calculate parameters of high metal concentration zones in the body of a man-made deposit.Practical implications. The research has proved the possibility of using metal-containing technogenic placers, and finding the zones of maximum metal concentration on the basis of the established regularities. The authors have developed a mathematical model of the gradual formation of technogenic deposits with zones of heavy metals concentration in metal-containing waste.

Purpose is to analyze the efficiency of hydromechanical amber extraction from sandy deposits relying upon the determined regularities concerning the effect of parameters while carrying out a series of laboratory tests and fullscale experiments.Methods. Laboratory tests and full-scale experiments (Volodymyrets amber-bearing deposit, village of Berezhnytsia) were carried out to analyze effect of the parameters of a hydromechanical technique on the velocity of amber extraction. The experiments also involved studies of occurrence medium; in this context, boiling process was modeled; and factors and parameters effecting suspense medium formation were researched. Methods of mathematical statistics were applied to obtain dependences describing mining parameters effect on amber extraction velocity.Findings. Basic parameters of hydromechanical technique, effecting amber extraction velocity, have been determined. Efficient values of air supply to provide maximum velocity of amber floating have been identified. Mathematical dependences, determining amber floating velocity depending upon air supply and mechanical effect frequency, have been obtained. In this context, amber production capacity is 90 to 95%. Basic parameters effecting amber mining (i.e. environmental density; amplitude of oscillations and their frequency; and water and air supply to sandy deposit of amber-bearing sand) have been defined.Originality. It has been first proved that amber floating velocity is of polynomial nature dependence upon environmental density where extremum is with 0.004 -0.006 m 3 /h air supply value; amber extraction experiences 2 -3 times intensification, if environmental density (ρ c ) is 1670 -1750 kg/m 3 , oscillation frequency is 26 -36 Hz, amplitude is A = 1.0 -2.4 mm, and air supply is q a = 0.004 -0.006 m 3 /h. In this context, amber floating (v) is 0.09 -0.12 m/s. If air supply is more than q a = 0.020 m 3 /h, amber extraction process stops. It has been first obtained polynomial dependence of amber flotation on oscillation frequency of operating device as well as on air supply to rock mass. Practical implications. The determined regularities of hydromechanical amber extraction from amber-bearing sand help make calculations, and select facilities for hydromechanical amber mining.

Purpose is to substantiate the parameters and factors in terms of which amber can be mined efficiently from sand deposits using hydromechanical method. Methods. Laboratory studies and full-scale experiments of amber-bearing sand with 2-50 mm fractions were carried out to substantiate velocity of amber buoying up to the sludge surface. Amber from Klessiv and Volodymyrets deposits were involved. Computer research relied upon Curve Fitting of the software environment Matlab. Analysis of amber particles, buoying up to the surface, relied upon a theory of particle motion within the sand formation, characterizing by motion with resistance of a dry friction type. Methods of mathematical statistics were applied; then dependences were plotted describing the effect of mining parameters on the amber buoying up velocity. Findings. The basic parameters of hydromechanical method and parameters, effecting buoying up velocity, and dependence of dimensions as well as weight of the amber fractions have been identified. Dependences of the dominant factor effect on the process of amber buoying up to the surface of sludge-like rock mass have been determined to improve the efficiency of amber mining.Originality. Maximum period of the analyzed amber fractions, differing in their diameters, is not longer than 4 minutes.The results of the experimental data as well as computer-based experimental data have helped define that 3 rd order polynom with corresponding rational coefficients for various amber fractions, occurring in the sand amber-bearing deposits, is the most adequate to describe the research. It has also been defined that velocity of amber buoying up from amber-bearing sand medium depends upon effect on the process of the dominant factors; and geometry of amber fractions and their weight making it possible to apply a hydromechanical mining method. Practical implications. The obtained regularities of hydromechanical mining of sand amber deposits help calculate and select facilities for hydromechanical mining of amber.

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ВИМІРЮВАННЯ ТОВЩИНИ ПЕРЕЗАРЯДНОЇ МІШЕНІ МОДИФІКОВАНИМ ЯДЕРНО-АНАЛІТИЧНИМ МЕТОДОМВиконано вимірювання товщини та однорідності по товщині тонкої самопідтримуючої вуглецевої плівки як перезарядної мішені для тандемного прискорювача. При вимірюваннях використовується неруйнівний ядерноаналітичний метод з прискореними до енергії 3,5 МеВ протонами. Метод було видозмінено з метою досягнення більшої точності, чутливості та розширення сфери застосування. У стандартну схему зворотного розсіяння іонів уводиться додатковий елемент -монітор-переривник пучка. Це змінює процедуру отримання експериментальних даних та спрощує формулу для розрахунків. Описано розроблені конструкції переривника та тримача мішеней. Товщина перезарядної мішені виявилася рівною в середньому 7,3 · 10 17 атомів/см 2 (~ 9,5 мкг/см 2 ). У порівнянні з оптимальною така товщина при прискоренні протонів є завеликою. Неоднорідність по товщині не перевищує похибку експерименту.Ключові слова: тандемний прискорювач, вуглецева перезарядна мішень, товщина плівки, спектрометрія зворотного розсіяння, видозмінений метод.