scholarly journals Sorption and Isomerselective Properties of Binary Sorbent Based on Supramolecular 4-(3-Hydroxypropyloxy)-4'-Formylazobenzene Liquid Crystal and Partially Methylated β-Cyclodextrin

2020 ◽  
Vol 20 (4) ◽  
pp. 54-62
Author(s):  
L. A. Onuchak ◽  
D. A. Tugareva ◽  
T. S. Kapralova ◽  
Yu. G. Kuraeva
Keyword(s):  
Liquid Crystal ◽  
Inverse Gas Chromatography ◽  
Gas Liquid Chromatography ◽  
Optical Isomers ◽  
Composite Sorbent ◽  
Standard Thermodynamic Functions ◽  
Smectic A ◽  
Structural Selectivity ◽  
Volatile Organic ◽  
Partially Methylated

The sorption and selective properties of a composite sorbent based on the supramolecular liquid crystal 4-(3-hydroxypropyloxy)-4'-formylazobenzene (HPOFAB) and partially methylated β-cyclodextrin heptakis-(2,6-di-O-methyl)-β-cyclodextrin (Me2,6-β-CD) have been studied by inverse gas chromatography. The standard thermodynamic functions of sorption on the smectic A phase of the sorbent for 29 volatile organic compounds of different classes were determined and compared with similar functions obtained on a column with “pure” HPOFAB. The reasons for the increase in the retention of all studied compounds (except for the optical isomers of butanediol-2,3) when Me2,6-β-CD (10 wt. %) added to HPOFAB are discussed. It was found that the mixed SA phase of the binary sorbent in conditions of gas-liquid chromatography has moderate values of structural selectivity and enantioselectivity to both low-polar terpene hydrocarbons and polar optical isomers (butanediols-2,3).

Freeze-fracture TEM of the helical smectic A* phase

1992 ◽  
Vol 50 (1) ◽  
pp. 278-279
Author(s):  
K.J. Ihn ◽  
R. Pindak ◽  
J. A. N. Zasadzinski
Keyword(s):  
Liquid Crystal ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Freeze Fracture ◽  
Smectic Phase ◽  
Layer Spacing ◽  
Screw Dislocations ◽  
Smectic A ◽  
Smectic Phases ◽  
Discrete Amount

A new liquid crystal (called the smectic-A* phase) that combines cholesteric twist and smectic layering was a surprise as smectic phases preclude twist distortions. However, the twist grain boundary (TGB) model of Renn and Lubensky predicted a defect-mediated smectic phase that incorporates cholesteric twist by a lattice of screw dislocations. The TGB model for the liquid crystal analog of the Abrikosov phase of superconductors consists of regularly spaced grain boundaries of screw dislocations, parallel to each other within the grain boundary, but rotated by a fixed angle with respect to adjacent grain boundaries. The dislocations divide the layers into blocks which rotate by a discrete amount, Δθ, given by the ratio of the layer spacing, d, to the distance between grain boundaries, lb; Δθ ≈ d/lb (Fig. 1).

Electric-Field-Dependent Tilt (Cone) Angle in a Chiral Smectic C Liquid Crystal Showing Electroclinic Effect in the Smectic A Phase

1991 ◽  
Vol 30 (Part 2, No. 4A) ◽  
pp. L612-L615 ◽  
Author(s):  
Ying-Bao Yang ◽  
Akihiro Mochizuki ◽  
Naoto Nakamura ◽  
Shunsuke Kobayashi
Keyword(s):  
Liquid Crystal ◽  
Electric Field ◽  
Cone Angle ◽  
Smectic A ◽  
Smectic C ◽  
Field Dependent ◽  
Smectic A Phase

Martingale solutions to a stochastic smectic-A liquid crystal model with multiplicative noise of jump type

2021 ◽  
pp. 2150046
Author(s):  
Theodore Tachim Medjo ◽  
Caidi Zhao
Keyword(s):  
Liquid Crystal ◽  
Multiplicative Noise ◽  
Galerkin Approximation ◽  
Martingale Solution ◽  
Smectic A ◽  
Liquid Crystal System ◽  
Skorokhod Representation Theorem ◽  
Crystal Model ◽  
2D And 3D ◽  
Martingale Solutions

In this paper, we are interested in proving the existence of a weak martingale solution of the stochastic smectic-A liquid crystal system driven by a pure jump noise in both 2D and 3D bounded domains. We prove the existence of a global weak martingale solution under some non-Lipschitz assumptions on the coefficients. The construction of the solution is based on a Faedo–Galerkin approximation, a compactness method and the Skorokhod representation theorem. In the two-dimensional case, we prove the pathwise uniqueness of the weak solution, which implies the existence of a unique probabilistic strong solution.

Smectic C to smectic A transition induced mechanically by the rupture of freely suspended liquid crystal films

Soft Matter ◽  
2017 ◽  
Vol 13 (17) ◽  
pp. 3199-3204 ◽  
Author(s):  
Torsten Trittel ◽  
Kirsten Harth ◽  
Ralf Stannarius
Keyword(s):  
Liquid Crystal ◽  
Liquid Crystal Films ◽  
Smectic A ◽  
Smectic C ◽  
Crystal Films ◽  
Freely Suspended
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