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Yttrium-modified bismuth-layered ferroelectric SrBi2Ta2O9 (SBT) with general formula SrBi2-xY3x/4Ta2O9 (where x = 0.00, 0.025, 0.05, 0.075 and 0.10) are prepared by mixed oxide route. The structural, dielectric, ferroelectric and conductivity behavior of the above compounds for each composition of Y is discussed. The formation of monophase materials is noted from the X-ray diffraction pattern. The structure of the grains is studied using Scanning electron microscopy. The variation of the dielectric permittivity with temperature at some particular frequencies manifests a diffuse order phase transition with reduced Tc (ferroelectric transition temperature) and ϵr (relative permittivity) with respect to higher concentration of Y. The ferroelectric properties in the materials are confirmed using hysteresis (P-E) loops. The remnant polarization of the materials is found to increase with the addition of Y while the coercive field follows the reverse trend. [ABSTRACT FROM AUTHOR]

A new, simple, specific, rapid, precise, highly accurate, reproducible and cost effective Ultraviolet-Visible spectrophotometric method was developed and validated, according to the International Harmonization Guidelines, for the determination of naringenin from solid lipid nanoparticles. Absorption maximum of Naringenin was found to be at 287.49nm in methanol. The linearity range was found to be 5-25μg/mL with high correlation coefficient value of 0.999. The detection and quantification limits were found to be 0.1879μg/mL and 0.5694μg/mL, respectively. This method was shown to be specific, selective, precise at the intra-day (relative standard deviation less than 0.7046%) and inter-day (relative standard deviation less than 1.5424%) level and accurate with recoveries between 98.77-100.43% (relative standard deviation less than 0.3924%). Method robustness observation indicates that method was robust. The suitability of the method for naringenin quantifications was assessed by the determination of entrapment parameters and by studying the naringenin release profile from SLNs. High entrapment efficiency (91.922 ± 0.717%) and drug loading (3.506 ± 0.027%) were observed. Kinetic models (zero order, first order, Higuchi, Hixson-Crowell, Korsmeyer-Peppas and Baker-Lonsdale) were used to fit the obtained release profile and to predict the in vivo performance of naringenin-loaded SLNs. An anomalous non-Fickian transport was found, which indicate a controlled drug release system. [ABSTRACT FROM AUTHOR]

An increase in the number of distressed bridges and the limited financial resources emphasize the need for an efficient bridge management system (BMS) for India. Assessment of the remaining life of bridges becomes an essential step in BMS, which involves modeling of complex deterioration mechanisms in concrete due to chemical attacks, such as carbonation, chloride, sulfate, and so on. Lack of information on material properties used in bridge construction, construction techniques, exposure condition, and maintenance quality adopted make the remaining life assessment of bridges more complicated. Therefore, a parametric study has been carried out to understand the deterioration of concrete bridges due to carbonation. Effect of carbonation on the initiation and propagation time of corrosion was also included in the study. Based on the study, modifications are suggested in the clauses of Indian concrete bridge design standard IRC: 21 (2000) so as to enhance the service life of bridges. [ABSTRACT FROM AUTHOR]

This article discusses the simulation, design and performance of an 80 kW strip electron gun. Electrons from an electrically heated, multisegmented tantalum filament are electrostatically focused to provide a sheet of electrons in the postanode region, that when bent through 270° along a circle of radius 120 mm by a uniform magnetic field, focuses on the target. This gun has been tested up to 80 kW (45 kVx1.8 A), and delivers power densities on the target in the range of 20 kW cm-2. The linear current density is uniform up to 20%, over a focal spot of dimension 80x5 mm2. Good correspondence between filament geometry and focal spot image of the electron beam on the target has been obtained, which is desirable in applications involving metal vapor coatings. This design is scaleable along the length of the focal spot without sacrificing uniformity, which is not possible in scanning or multiple pencil-type of electron guns. Experimental measurement of gun parameters such as position of filament in relation to the cathode opening, distribution of current along the length of the beam, focal spot size, extraction efficiency, etc., along with data concerning electron beam quality as a function of various parameters, are presented. The performance of this gun under different experimental conditions, as well as the simulation and modeling using an in-house three-dimensional beam dynamics code, is discussed. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The article reviews the film "No One Killed Jessica" starring Vidya Balan and Rani Mukherjee.