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We have extended the experimental approach, used by Yu. A. Nastyshyn et al. [J. Appl. Phys. 86 , 4199 (1999)] for measuring polar anchoring strength, to measure the twist elastic constant in nematic liquid crystal. The method implies measurements of phase retardation changes in liquid crystal under the action of magnetic field. The obtained experimental data were fitted with the predictions of elastic theory. We found that the value of the measured elastic constant, K_{22} , is in good agreement with those described in literature.

Electrical properties of 1- w m-thickness preferentially -oriented PZT ferroelectric films of rhombohedral composition near the morphotropic boundary prepared by RF magnetron sputtering of a ceramic target containing additionally 10 mol % lead oxide were studied. The data obtained suggests n -type conductivity due to lead oxide excess in the films. Such films were characterized by combination of a self-polarization and migratory polarization. It was shown that the self-polarization - thickness distribution was nonuniform with the most poled state localized near the bottom interface of the thin ferroelectric capacitor. The mechanism, which lies in base of such self-polarization, is related to the electron charging of the bottom interface of the structure during cooling after the high-temperature crystallization of the PZT film in the absence of the top electrode, and to bulk poling of the film by the charged interface. Heat treatment of such capacitor led to elimination of self-polarization. The obtai...

New N-arylidene (S)-1-phenylethylamines with ester group in arylidene fragment have been synthesized. The chiral dopants helical twisting power and temperature dependence of the induced cholesteric helical pitch in LC systems based on 4-pentyl-4′-cyanobiphenyl have been studied as well as selective light reflection spectra and their temperature dependences for systems including nematic E63 (Merck) and new chiral components. An influence of the chiral dopant molecular structure on the mentioned characteristics of LC systems investigated was revealed. The induced cholesteric compositions with temperature-independent selective light reflection in visible range have been obtained.

Chiral dopants are optically active substances used in liquid crystal systems. We have investigated the helical twisting power and its temperature dependences for the systematic rows of optically active organic compounds synthesized on the base of 2-methylbutanol and e-menthol. The compounds differ by molecular, chemical and spatial structure. Correlation between the value of helical twisting power and molecular structure of chiral dopants is analyzed. The mesogenity of new chiral dopants is also discussed.

The structure of Pb(Zr, Ti)O3 films grown on u-Al2O3 (0112) substrates by the RF-sputtering and annealed in the PbO atmosphere has been studied by X-ray diffraction and TEM methods. The Pb(Zr, Ti)O3 phase has been found to be of the perovskite type structure. The films had the strongly pronounced texture formed by large grains with the (110) axis oriented nearly normal to the substrates. The values of the grain size and the grain misorientations have been obtained by TEM. TEM microdiffraction analysis showed the growth of Pb(Zr, Ti)O, grains to be the epitaxial one.

Comparison of electrooptic characteristics of LCD's with orienting structures made by vacuum and non-vacuum methods is demonstrated

(1985). STRATIGRAPHY OF SEDIMENTS OF THE CENTRAL AND EASTERN MEDITERRANEAN SEA. International Geology Review: Vol. 27, No. 5, pp. 546-551.