The widespread use of various substances in the flotation of minerals clogs wastewater, which, poisoning reservoirs, endangers the normal existence of wildlife.

Кинетика растворения и методы фазового анализа соеди­нений сурьмы изучались неоднократно. Для исследова­ния кинетики растворения Sb₂S₃и Sb₂0₃в растворах КОН с целью возможности использования их для фазового анализа были взяты полидисперсные образцы этих соединений сурьмы (чда) ....

Обычно применяемые для разделения окисленных и суль­фидных соединений висмута соляная и азотная кис­лоты не позволяют количественно разделить окисленные и сульфидные минералы висмута ...

High refractoriness (2715°), slag resistance, low thermal and electrical conductivity at high temperatures, mechanical strength and thermal stability under sharp temperature fluctuations make zirconium dioxide a very valuable source of highly refractory material, especially after it was discovered that cracking during heating of products made of pure zirconium dioxide, caused by the transformation of one modification into another at a temperature of 1000°, can be eliminated by adding more than 4% magnesium or calcium oxide, which form stable solid solutions with zirconium dioxide. In the Soviet Union there are numerous deposits of zirconium ores, ensuring their industrial use. As for magnesium oxide and calcium oxide, these source materials are available in unlimited quantities. All this shows that the study of the ternary system Zr0₂— MgO — СаО has not only theoretical but also significant practical interest.