Reclamation of coal preparation dumps

Experiments are conducted to improve the coal preperatiom dumps at PAO Avdeevskii Koksokhimicheskii Zavod and to recultivate and utilize the wastes rock by means of humic preparations from lignite and other wastes rock. Reclamation and utilization of blends of industrial wastes rock proves possible, especially at use of humic preparations.     

Acoustostimulated changes in the density of surface states and their energy spectrum in <Emphasis Type="Italic">p</Emphasis>-type silicon single crystals

The effect of ultrasonic treatment at various powers on the density N _SS of surface states and their energy spectrum in p-type silicon single crystals has been studied. It is established that, depending on the regime of ultrasonic treatment, N _SS can either increase or decrease compared to that in the initial single crystals. This is accompanied by a redistribution of the total charge of the surface states over the silicon bandgap width. This phenomenon is related to the fact that an acoustic wave, being an energy carrier, modifies a defect subsystem of the crystal by redistributing the impurity atoms and by generating new defects.