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We have prepared the composites of a room temperature nematic liquid crystal mixture by dispersing small fractions of Multi-Walled Carbon Nanotubes into its matrix. The electro-optical and dielectr...

We have prepared the composite of a room temperature nematic liquid crystalline material namely 4-(trans-4′-n-hexylcyclohexyl) isothiocyanatobenzoate (6CHBT) and silver nanoparticles (AgNPs...

We have prepared the composites of a room temperature Nematic Liquid Crystals and Single-Walled Carbon Nanotubes. Effect of dispersion of nanotubes on various dielectric and electro-optic p...

Thermodynamic and electro-optical characterization of a ferroelectric liquid crystalline material, namely ((S) (+) 4-(1-methylheptyloxy) phenyl 4′-octyloxybiphenyl-4-carboxylate) possessing paraelectric SmA*, ferroelectric SmC*, hexatic SmBh* and SmI* phases has been carried out. Phase identification has been done by optical and thermodynamic studies. Switching parameters viz. spontaneous polarization, switching time and rotational viscosity have been determined. The spontaneous polarization has been found to increase with decreasing temperature in SmC* phase. The switching time is found of the order of few milliseconds.

We have prepared the composites of a room temperature nematic liquid crystalline material namely 4-(trans-4′-n-hexylcyclohexyl) isothiocyanatobenzoate (6CHBT) and gold nanoparticles (GNPs). Thermodynamic, electro-optical and dielectric properties have been investigated. Effect of dispersion of GNPs on various electro-optical and display parameters of host liquid crystalline material have been studied. Physical parameters such as threshold voltage, dielectric anisotropy and splay elastic constant have altered for composite systems. Due to the dispersion of GNPs, nematic to isotropic transition temperature is significantly increased. Relaxation frequency corresponding to flip-flop motion of the 6CHBT molecules about their short axes has increased due to the presence of GNPs.

Thermodynamical, optical, dielectric and electro-optical characterisation of nematic liquid crystals (LCs) and silver nanoparticle (NP) composites have been carried out. Transition temperatures of pure and composites systems have been measured. Thermodynamical studies suggest increase of clearing temperature of the composite material as compared to the pure material. Threshold voltage for switching from bright to dark state and splay elastic constant of the pure and composite materials have been determined. From frequency dependence of dielectric measurements, permittivity, loss, relaxation frequency and dielectric strength of flip-flop mechanism of LC molecules in the nematic phase have been calculated. Dielectric properties of composites have been explained in reference of Maier and Meier theory. The effects of doping of NPs on dielectric and electro-optic properties of LC-NP composites have been discussed.

The effect of row spacings (45, 60 and 75 cm) and various amounts of nitrogen fertilizer (0,100,200 and 300 kg N/ha) on plant growth, essential oil production and composition of Scotch spearmint was studied in the field during 1987 and 1988 in Lucknow, India. Nitrogen application increased plant height and leaf area index while decreased leaf-stem ratio and oil concentration, irrespective of row spacings. The green herbage and oil yields increased significantly up to an application of 200 kg N/ha at 45 or 60 cm row spacing as against up to 300 kg N/ha at 75 cm row spacing. The higher N application at 75 cm row spacing, however, did not increase oil yield compared to application of 200 kg N/ha at 60 cm row spacing. Row spacing influenced various response functions and optimum N rate. At optimum N, response per kg N, net return per kg N and benefit-cost ratio were highest at 60 cm row spacing. Oil concentration and composition in green herb were related to leaf area index and N concentration in the...

Mehra, U.R., Challa, J. and Singh, U.B. 1993. Nutrient utilisation and rumen fermentation pattern in buffaloes fed rations supplemented with formaldehyde treated urea molasses mineral blocks. J. Appl. Anim. Res., 4: 67–72. To overcome the problem of hygroscopic nature of urea molasses mineral blocks (UMMB), formaldehyde and phosphoric acid were added to these (FUMMB). Eight postulated male buffaloes weighing around 350 kg were divided into two groups and were offered the UMMB without or with formaldehyde and phosphoric acid as a lick. One kg wheat bran and ad libitum wheat straw were fed individually. The UMMB contained 37 parts sugarcane molasses, 10 parts each of urea, cement and fish meal, 32 parts wheat bran, 1 part common salt and 0.1 part vitablend. Besides these, 225 ml formaldehyde and 45 ml phosphoric acid per 100 kg block were added to FUMMB. Dry matter intake, digestibility and rumen fermentation pattern were similar in both the groups. As FUMMB was not found to be hygroscopic, it is r...