Miscibility Studies of Bismesogen CBnCB Forming Nematic Twist-Bend Phase with Cyanobiphenyls nCB.

This work aims to determine how the nematic twist-bend phase (N) of bismesogens containing two rigid parts of cyanobiphenyls connected with a linking chain containing n = 7, 9, and 11 methylene groups behaves in mixtures with structurally similar cyanobiphenyls nCB, n = 4-12, 14. The whole phase diagrams are presented for the CB7CB-nCB system. For the other systems, CB9CB-nCB and CB11CB-nCB, only curves corresponding to N-N phase transition are presented.

Determination of tilt angle and its behavior in chiral smectic phases by exploring molecular conformations using complementary methods.

Density functional theory (DFT) calculations and x-ray diffraction techniques were employed to evaluate the value of the tilt angle in ferroelectric smectic C^{*} and antiferroelectric smectic C_{A}^{*} phases. Five homologues from the chiral series denoted as 3FmHPhF6(m=2,4,5,6,7), based on 4-(1-methylheptyloxycarbonyl) phenyl 4'-octyloxybiphenyl-4-carboxylate (MHPOBC), were studied. Two types of conformations for the nonchiral terminal chain (fully extended and gauche) and three types of deviation from the rodlike shape of the molecules (hockey stick, zigzag, and C shape) were computationally considered.

Uncompleted polymerization and cytotoxicity of dental restorative materials as potential health risk factors.

Introduction: Composite materials used in dentistry indicate adverse biological effects in laboratory conditions. One reason for this activity is incomplete conversion of their polymer matrix, favoring chemical instability and release of biologically harmful components to the external environment.

Aim: The aim of the study was to assess the degree of conversion of restorative materials commonly available on the European market and to examine the cytotoxic effects of their eluates in vitro.

Dielectric spectroscopy of a binary mixture of liquid crystals showing wide temperature range twisted grain boundary phase with re-entrant cholesteric phase.

There are only few materials, which have shown long temperature range twisted grain boundary (TGB) phases. One such material is the chiral binary mixture of 7OCB and 5* CBB (mole ratio 0.8 and 0.