Surface structure of equimolar mixture of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([CCIm][TfN]) and 1-ethyl-3-methylimidazolium tetrafluoroborate ([CCIm][BF]) is studied using high-resolution Rutherford backscattering spectroscopy (HRBS) and molecular dynamics (MD) simulations. Both HRBS and MD simulations show enrichment of [TfN] in the first molecular layer although the degree of enrichment observed by HRBS is more pronounced than that predicted by the MD simulation. In the subsurface region, MD simulation shows a small depletion of [TfN] while HRBS shows a small enrichment here. This discrepancy is partially attributed to the artifact of the MD simulations. Since the number of each ion is fixed in a finite-size simulation box, surface enrichment of particular ion results in its artificial depletion in the subsurface region.

No abstract

No abstract

No abstract

This paper deals with an analysis of the stress distribution in different design solutions of upper crossbeam of presses CKV type. Performed was design optimization in terms of minimum weight, maximum rigidity and uniformity of stress distribution in all sections. During optimization is considered the maximum force of technological operation upsetting. The performed optimization and reduction of the stress will improve the fatigue strength. It results also in increased lifetime. This whole process shows way of machine part design preparation.