Frequency dispersion studies on proton spin-lattice relaxation rates of a liquid crysal (4’-octyloxy-4-cyanobiphenyl) embedded in Aerosil matrix show significant increase at low frequencies (sub-MHz regime) relative to the bulk sample, and are interpreted as primarily due to slow reorientations near the surface ordered layers mediated by translation displacements. The computed exponent in the p...

The effects of dispersed aerosil nanoparticles on two of the phase transitions of the thermotropic liquid-crystal material 4-n-pentylphenylthiol-4(')-n-octyloxybenzoate (8;S5) have been studied using high-resolution x-ray diffraction techniques. The aerosils hydrogen bond together to form a gel which imposes a weak quenched disorder on the liquid crystal. The smectic-A fluctuations are well cha...

The viscous flow behavior of a 12.5 vol% hydrophobic fumed silica (Aerosil® R816) suspension in polypropylene glycol low molecular weight (PPG400) was studied stress-controlled rheometer. steady curve showed shear thickening between two thinning regions. Time-dependent viscosity response provoked by step changes stresses corresponding to the shear-thickening region apparently agrees with thixot...

In the present study an attempt was made to formulate and evaluate Calcium and Vitamin K3 tablet using wet granulation technique incorporating various Excipients like Starch Powder, Starch Paste, Magnesium Sterate, Aerosil, Talc, Lactose, Vitamin K Liquid form and Water. The Formulated tablets were evaluated for different physicochemical properties like rheological properties, weight variation,...

The dynamics of a thixotropic silica aerosil gel dispersed in an octylcyanobiphenyl liquid crystal were directly probed by x-ray intensity fluctuation spectroscopy. For all samples, the time-autocorrelation function of the gel was well described by a modified-exponential function over the q range studied. Compared to a pure gel sample, a dilute (0.06 g cm(-3)) gel embedded within the liquid cry...

The molecular dynamics of [-SiDMe(2)] grafted on two amorphous silica materials, mesoporous SBA and non-porous Aerosil, was investigated by deuteron ((2)H) solid-state NMR spectroscopy. Quadrupole echo (QE), quadrupole Carr-Purcell-Meiboom-Gill (QCPMG) and magic angle spinning (MAS) spectra were recorded as a function of temperature. These were analyzed to determine the rates and trajectories o...