High-resolution x-ray scattering studies of the nonpolar thermotropic liquid crystal 4-n-pentylphenylthiol-4'-n-octyloxybenzoate (8S5) in aerosil gel nanonetworks reveal that the aerosil-induced disorder significantly alters both the nematic to smectic-A and smectic-A to smectic-C phase transitions. The limiting 8S5 smectic-A correlation length follows a power-law dependence on the aerosil dens...

There is a well-known de Gennes coupling between the scalar nematic order parameter S and the smectic density-wave amplitude /Psi/, which causes the nematic-smectic-A phase transition to cross over from second order to first order via a tricritical point. This sort of crossover is observed for numerous liquid crystals (LCs) with small to moderate nematic ranges. Recent studies of LC+aerosil sys...

We have studied the effects of quenched random disorder created by dispersed aerosil nanoparticle gels on the nematic to smectic- A (N- SmA ) and smectic- A to reentrant nematic ( SmA -RN) phase transitions of thermotropic liquid-crystal mixtures of hexyloxycyanobiphenyl (6OCB) and octyloxycyanobiphenyl (8OCB). These effects are probed using high-resolution synchrotron x-ray diffraction techniq...

The main components for tablet formulations are the fillers, binders, crushers, thinners and lubricants. Among these components, binders play a key role on powder cohesion properties during formation of granules. In this study, turmeric extract tablets were formulated using 15 g extract, 35 aerosil, 12.8 lactose, 1% magnesium stearate, 200 ml aquadest gelatin as binder. To evaluate effect formu...

High-resolution x-ray diffraction and ac-calorimetric experiments have been carried out on the liquid-crystal octyloxycyanobiphenyl in which aerosil particles are dispersed. The measurements were made over a temperature range around the bulk nematic to smectic-A transition temperature. At this transition the liquid crystal breaks translational symmetry in a single direction. The silica particle...

Preformulation is an important step in the rational formulation of an active pharmaceutical ingredient (API). Micromeritics properties: bulk density (BD) and tapped density (TD), compressibility index (Carr's index), Hauser's ratio (H), and sieve analysis were performed in order to determine the best excipients to be used in the formulation development of omeprazole magnesium enteric coated tab...

Comprehensive x-ray scattering studies have characterized the smectic ordering of octylcyanobiphenyl (8CB) confined in the hydrogen-bonded silica gels formed by aerosil dispersions. For all densities of aerosil and all measurement temperatures, the correlations remain short range, demonstrating that the disorder imposed by the gels destroys the nematic (N) to smectic-A (SmA) transition. The sme...

Since Cohn's cold ethanol method was introduced into routine practice of plasma fractionation in this country, little attention has been paid to other approaches for isolating or fractionating plasma proteins , at least in the level of industrial production. Recently, however, in Western European countries , usefulness of selective adsorption of plasma proteins to various adsorbents is attracti...

Slow molecular processes in a nematic liquid crystal confined to random porous network formed by aerosil particles M. Rajeswari a , S. Dhara a , K. Venu b , V.S.S. Sastry a & R. Dabrowski c a School of Physics, University of Hyderabad, Hyderabad 500 046, Andhra Pradesh, India b Soctronics Technologies Pvt. Ltd, Hyderabad 500 034, Andhra Pradesh, India c Institute of Chemistry, Military Universi...

The reaction of four different basic ionic liquid precursors with Aerosil 300 is presented. Chemisorbed imidazolium and phosphonium cations, with silanolate anions as part of the silicatic support, were obtained and investigated with various solid state NMR techniques.