V. G. Mayorov, senior researcher; A. I. Nikolaev, deputy director of scientific work, e
-mail: nikol_ai@chem.kolasc.net.ru; V. K. Kopkov, engineer; O. P. Adkina, leading engineer, IKhTREMS of Kolsky Research Center, RAS, Appatity city, Murmansk region.

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