Christo Tzachev

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This is an early access version, the complete PDF, HTML, and XML versions will be available soon. Open AccessArticle by Iskra Z. Koleva SciProfiles Scilit Preprints.org Google Scholar * and Christo T. Tzachev SciProfiles Scilit Preprints.org Google Scholar Faculty of Chemistry and Pharmacy, Sofia University “St. Kliment Ohridski”, 1 J. Bourchier Blvd., 1164 Sofia, Bulgaria * Author to whom correspondence should be addressed.