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The effect of pressure of pelletisation on the density, microstructure, dielectric, ferroelectric, piezoelectric and energy storage density of B-site Zr doped barium titanate has been studied. X-ray diffraction confirmed that zirconium form complete solid solution with barium titanate. It has been observed that 4 ton/cm2 is an optimum pressure of pelletisation which gives maximum density, maximum dielectric constant, maximum piezoelectric constant and high energy storage density with efficiency of 67.68%. There is a good correlation among the density, grain size, dielectric, ferroelectric and piezoelectric properties. These results suggest that this material has a potential for energy storage applications. [ABSTRACT FROM AUTHOR]

LiNbO3has been synthesized by solid state sintering technique. The glass 30Li2O: 50B2O3: 10 Nb2O5: 10SiO2has been synthesized by conventional quenching technique. Different weight percentage of glass was added into LiNbO3ceramics and sintered at different temperatures. The samples were characterized by using X-Ray Diffraction, Density and Scanning Electron Microscope. The dielectric and ferroelectric measurements of these ceramics suggests that the addition of glass has helped in improving its properties. The LiNbO3ceramic with 5 wt% glass addition has shown optimum properties among the ceramics prepared. [ABSTRACT FROM AUTHOR]

PbTiO3glass-ceramics were prepared by following two stage heat treatment schedule. The effect of heat treatment duration on the physical properties of glass-ceramic was studied. The density, CTE, dielectric constant and ferroelectric properties varied systematically with heat treatment duration and exhibited an optimum for 32 h. These properties have a good correlation with the volume fraction of lead titanate phase crystallized in the glass-ceramics. Impedance spectroscopy was used to analyse the behaviour of glass-ceramic samples. The studies of ferroelectric properties show that PbTiO3glass-ceramics has a potential for high temperature applications. [ABSTRACT FROM PUBLISHER]

Glasses of compositions (50 -X) PbO-X CaO-25 TiO2-25 B2O3 (where X = 0,5,10 and 15 mol%) were prepared by conventional quenching technique. The glass samples were converted to glass ceramics by two stage heat treatment schedule. The XRD results confirmed the formation of ferroelectric PbTiO3 as a major phase in the glass ceramics. For all the CaO added samples the dielectric constant as a function of temperature, exhibit a peak around 475°C, which is close to the Curie temperature of PbTiO3. The hysteresis measurement supports the ferroelectric nature of the glass ceramics. [ABSTRACT FROM PUBLISHER]

Glass samples with composition of (50-X) PbO-X BaO-25 TiO2-25B2O3 (where X = 0, 5, 10 and 15 mol%) were prepared using conventional quenching technique. The amorphous nature of glass samples were confirmed by XRD. The glass transition temperature, Tg and crystallization temperature Tc were determined from the DTA. It has been observed that the addition of BaO enhances the Tg and reduces the Tc. These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The glass ceramic samples were characterized by XRD, SEM and dielectric constant measurements. The dielectric constant for all the glass ceramic samples was observed to be higher than that of corresponding glass samples. Further, with addition of BaO the dielectric constant for glass ceramic samples increases up to 10 mol% of BaO and beyond this concentration it decreases. The XRD results revealed the formation of ferroelectric Lead Titanate as a major crystalline phase in the glass ceramics. This is supported by the SEM results which show rounded crystallites of lead titanate. This explains the enhancement in the dielectric constant. The addition of BaO to the glass contributes to the formation of BaB2O4 and Barium-Titanium-Borate (BTB) phases. Additional phases observed in these glasses include PbB2O4 and PbB2O7. This has been supported by SEM results indicating needle-like crystals in glass ceramic samples containing higher concentration of BaO. The observed hysteresis (P vs. E) loop at room temperature confirmed the ferroelectric nature of these glass ceramics. [ABSTRACT FROM AUTHOR]

The lead titanate based glass samples were prepared by conventional quenching technique. The Tg, Tc and density of the glass samples were measured. The glass samples were converted to glass ceramics by two stage heat treatment schedule. The dielectric constant has been studied for the glass and glass ceramics. The glass ceramic sample obtained by optimized heat treatment schedule exhibited maximum density and dielectric constant due to precipitation of crystalline PbTiO3 phase. [ABSTRACT FROM AUTHOR]

The study of electrical conductivity of 30Li2O : (70 - x) B2O3: xV2O5 glass samples has been carried out. The results have been explained by dividing the temperature range into two regions. In region I, conductivity shows Arrhenius behaviour for all the samples. The conductivity increases with addition of V2O5. The results have been explained in the light of Anderson and Stuart Model. In region II, an anomalous enhancement in the conductivity is observed for all the samples up to certain temperature beyond which the conductivity decreases. The enhancement in the conductivity in the annealed glass sample has been attributed to nanocrystallization. [ABSTRACT FROM AUTHOR]

Aim: The classic variants in superior articular facets of atlas such as, variability in shape, presence of notch, constrictions, partial or complete separation of facets, and presence of pressure facets, have been reported to a limited extent in relation to ergonomics of cranio-vertebral joint. Objective: The objectives of the present study were to report the analyzed morphological features and metrical values of superior articular facets of the atlas. The morphological features which were included in this study were variability in shapes, constrictions and partial or complete separation of facets. The metrical measure included the surface area measurement of the facets. Material and Methods: This study was carried out on 50 (100 sides) dry atlas vertebrae from the Department of Anatomy, St John's Medical College, Bangalore, India. The superior articular facets were studied for the shape and symmetry, constrictions and partial or complete separation of facets. The surface area of the facets were measured by using Image J (Image processing and analysis in JAVA) tool, that was primarily designed to measure and analyze different metrics. Results: The mean surface area on the right side was 157.3 ± 29.02, and on the left side, it was 158.5 ± 24.85. Oval, irregular, kidney and figure of eight shapes were observed either on both sides or on one side. Bilateral constrictions of facets were seen in 58 % of vertebrae. Bilateral, complete separations of facets were seen in 30% of vertebrae Conclusion: The observations of the present study are important to understand the ergonomics of the cranio-vertebral joint and they are helpful for academicians, neuro-surgeons, clinicians and radiologists in day to day clinical practice. [ABSTRACT FROM AUTHOR]

An experiment was conducted during 2005-06 to study the effect of fertilizers, biofertilizers and micronutrients on plant growth, seed yield and quality of brinjal. The results indicated that, application of 100:100*:50 kg NPK per ha + Azospirillum + Phosphate solubilizing bacteria (PSB) each @ 125 g per ha (root dipping) along with zinc sulphate (0.2%) spray recorded significantly higher plant height (89.47 cm), number of branches (32), number of leaves (87), number of fruits (20), fruit yield (27.06 t/ha), number of seeds per fruit (1852), 1000-seed weight (7.90 g), seed yield (633 kg/ha), percentage of germination (97), field emergence (91), seedling vigour index (2024) and seedling dry weight (48.84 mg) over 125:100:50 Kg NPK / ha (RDF) at Dharwad conditions. [ABSTRACT FROM AUTHOR]