A two level mathematical model of deformation of polycrystalline metals and alloys with consideration for grain structure refinement is proposed. The fragmentation criterion for a crystallite based on the analysis of accumulated inelastic strain and the current form is given. The moment factors appearing inside the polycrystalline aggregate during inelastic deformation are considered in the description of crystallite fragmentation. The derived modeling results for different loading processes of polycrystalline copper illustrate the capabilities of the proposed model.

Introduction: Present study describes the antimicrobial activity and free radical scavenging capacity (RSC) of essential oil from Mentha longifolia (L.) Huds. Aim of this study to investigate the quality, antimicrobial andantioxidant activity of wild species Mentha longifolia essential oil from Bosnia and Herzegovina.Methods: The chemical profi le of essential oil was evaluated by the means of gas chromatography-mass spectrometry (GC-MS) and thin-layer chromatography (TLC). Antimicrobial activity was tested against 6bacterial strains. RSC was assessed by measuring the scavenging activity of essential oils on 2,2- diphenyl-1-picrylhydrazil (DPPH).Results: The main constituents of the essential oil of M. longifoliae folium were oxygenated monoterpenes,piperitone oxide (63.58%) and 1,8-cineole (12.03%). Essential oil exhibited very strong antibacterial activity.The most important antibacterial activity essential oil was expressed on Gram negative strains: Escherichia coli, Pseudomonas aerginosa and Salmonella enterica. subsp.enterica serotype ABONY. Antioxidant activity was evaluated as a RSC. Investigated essential oil was able to reduce DPPH radicals into the neutral DPPHH form (IC50=10.5 μg/ml) and this activity was dose –dependent.Conclusion: The study revealed signifi cant antimicrobial activity of the investigated essential oil. The examined oil exhibited high RSC, which was found to be in correlation to the content of mainly monoterpeneketones and aldehydes. These results indicate that essential oils could serve as safe antioxidant and antiseptic supplements in pharmaceuticals.