00522naa#a2200169#i#450# EN\\bibl\80702 20241124100834.7 2076-0655 20151225b2015####ek#y0engy0150####ca RUS RU Interaction of silicate minerals of various structure with ammonium hydrodifluoride Journal article Moscow Individual Entrepreneur Svetlana Vasilievna Samchenko 2015 5 с. Journal article local Nesterov D P tsilicates.ru