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Information × Registration Number 0211U002901, 0108U001485 , R & D reports Title Investigation of the influence of external factors on the nature of the orientationfl ordering in the wall-adjacent layers of liquid. popup.stage_title Head Mikhailenko V.I., Registration Date 10-03-2011 Organization Odessa National Maritime Academy popup.description2 We worked out a theoretical model of two-component liquid disposed near the solid surface. The model is based on the existence of a boundary liquid layer, formed by monomers and dimers, which interact among themselves and with the solid substrate dispersion forces. Isotropic part of the dispersion interaction is modeled usually by Lennard-Jones potential. Also it was worked out an alternative theoretical model, which assumes that the dispersion interaction between molecules of liquid and solid substrate includes two or three molecular layers, and further in the bulk liquid this interaction may be neglected. However, the orientational ordering in wall-adjacent layers extended from the solid substrate due to relay trace interaction from layer to layer. Depending on the specific relationships can be formed near the solid surface of one of three phases: 1) an isotropic liquid, 2) the nematic phase, 3) epitropic liquid crystal (ELC). Experimental studies of the absorption spectra of nitrobenzene and anisole showed that near the surface of a solid quartz substrate a two-phase system - ELC and isotropic bulk liquid phase is formed. Bulk liquid is separated from ELC phase by relatively sharp boundary. ELC phase consists mainly of dimers, and the isotropic phase - of the monomers. Results of experimental studies agree well with calculations performed within the two-component model, With increasing of a temperature a gradual decrease in the ELC thickness is observed simultaneous with shifting of the equilibrium between monomers and dimers in favour of the monomers. However, at relatively high values of the dimer bonding energies it concentration increases at first, and then at higher temperatures decreases. Homeotropic orientation of molecules in the boundary lubricant layer enhances its anti-wear performance and resistance to friction with the slight increase. Planar orientation of the molecules also reduces the force of friction, but it leads to increased wear. Product Description popup.authors Горюк А.А. Кіріян С.В. Кресік З.І. Поповський О.Ю. Птащенко Ф.О. Ханмамедов С.А. Шакун К. С. popup.nrat_date 2020-04-02 Close