Director configurations in nematic droplets with tilted surface anchoring

The polymer dispersed nematic liquid crystal (LC) with the tilted surface anchoring has been studied. The droplet orientational structures with two point surface defects – boojums and the surface ring defect – are formed within the films. The director tilt angle α = 40° ± 4° at the droplet interface and LC surface anchoring strength W_s ~ 10^–6 (J m^?2) have been estimated. The bipolar axes within the studied droplets of oblate ellipsoidal form can be randomly oriented are oriented randomly relatively to the ellipsoid axes as opposed to the droplets with homeotropic and tangential anchoring.     

Electrically controlled local Frédericksz transition in a layer of a nematic liquid crystal

A local Frédericksz transition caused by electrically controlled surface anchoring in a nematic liquid crystal has been implemented owing to the displacement of surface-active ions. In the initial case, the nematic is homeotropically aligned by monomolecular layers of cetyltrimethylammonium bromide cations adsorbed on the surface of substrates. One of the substrates in a static electric field becomes free of a cation layer and specifies planar boundary conditions; as a result, a homeoplanar orientation structure is formed. The features of the dynamics of the optical response of the cell under study that are characteristic of the effect under consideration are discussed.     

Inverse regime of ionic modification of surface anchoring in nematic droplets

JETP Letters - It was found that the effect of the ionic modification of anchoring in liquid-crystal droplets can be implemented in the inverse regime. Droplets of 4-n-pentyl-4′-cyanobiphenyl...     

Experimental determination of the ψ′-potential by means of electron photoemission from metals into electrolyte solutions

The measurements of the photoelectron emission current from a metal electrode into electrolyte solution can be used for direct determination of the ψ′-potential. The limits of applicability of this method are discussed. The values of the ψ′-potential measured at mercury and lead electrodes in HCl solutions are in good agreement with those calculated by means of the Gouy-Chapman theory.     

Determining the instrumental reliability of quality control in terms of Owen's functions for the case of normally distributed controlled parameters and measurement errors

Translated from Issledovaniya po Prikladnoi Matematike, Kazan', No. 14, pp. 166–198, 1987.     

Orientational structures in nematic droplets with conical boundary conditions

Slightly diluted magnetic systems described by the disordered three-dimensional Potts model with the number of spin states q = 3 are studied in the case of a simple cubic lattice. The position of the tricritical point in the phase diagram is determined using the histogram Monte Carlo technique.