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1.
Multimedia Tools and Applications - Present era is marked by exponential growth in transfer of multimedia data through internet. Most of the Internet-of-Things(IoT) applications send images to...  相似文献   
2.
Wireless sensor networks (WSNs) are a kind of communication networks having independent sensor nodes that form multi-hop ad hoc network to transfer data. In the past few years, various transport control protocols in wireless sensor networks (WSNs) have been developed and proposed in the literature. In this paper, we have analyzed pump slowly, fetch quickly (PSFQ) protocol and presented an improved transport layer protocol for wireless sensor networks. The improved protocol has been analyzed based on various factors such as average latency and average error tolerance and it is found that the proposed protocol is better than PSFQ in terms of these factors.  相似文献   
3.
Beans of Phaseolus are an important food crop both economically and nutritionally, and are cultivated and consumed worldwide. With ever rising costs of meats and fresh fruits and vegetables, dry beans are expected to contribute more to the human nutrition in coming years. Traditionally, they have been referred to as "poor man's meat" and have contributed significantly to the diets of many people of several countries in Asia, Africa, Middle East, and South America. In recent years, a renewed interest in bean research in Western European countries and the U.S. is evident. In this review, certain biochemical, technological, nutritional, and toxicological aspects are discussed and the limitations and problems associated with dry beans of Phaseolus as human food are addressed.  相似文献   
4.
Undoped and Ga doped ZnO thin films (1% GZO, 3% GZO and 5% GZO) were grown on c-Al2O3 substrates using the 1, 3 and 5 at. wt.% Ga doped ZnO targets by pulsed laser deposition. X-ray diffraction studies revealed that highly c-axis oriented, single phase, undoped and Ga doped ZnO thin films with wurtzite structure were deposited. Micro-Raman scattering analysis showed that Ga doping introduces defects in the host lattice. The E2High mode of ZnO in Ga doped ZnO thin film was observed to shift to higher wavenumber indicating the presence of residual compressive stress. Appearance of the normally Raman inactive B1 modes (B1Low, 2B1Low and B1High) due to breaking of local translational symmetry, also indicated that defects were introduced into the host lattice due to Ga incorporation. Band gap of the Ga doped ZnO thin films was observed to shift to higher energy with the increase in doping concentration and is explicated by the Burstein-Moss effect. Electrical resistivity measurements of the undoped and GZO thin films in the temperature range 50 to 300 K revealed the metal to semiconductor transition for 3 and 5% GZO thin films.  相似文献   
5.
Context: The clinical applications of cilostazol (CLZ) are limited by its low aqueous solubility (<5?µg/ml) and high biovariability.

Objective: The aim of this study was to enhance the solubility of CLZ by forming inclusion complexes (ICs) with beta cyclodextrin (β-CD) and formulating them into oral disintegrating tablets.

Methods: Phase solubility study of CLZ with β-CD was performed in water. Job’s plot was constructed to determine the stoichiometry of ICs. ICs, prepared by spray-drying technique, were characterized using Fourier transform infrared spectroscopy, differential scanning calorimetry, hot stage microscopy, powder X-ray diffraction and nuclear magnetic resonance. Molecular modeling studies were performed to understand the mode of interaction of CLZ with β-CD. The formulation process was undertaken using a reproducible design of experiment generated model, attained by variation of diluents and disintegrants at three levels. Tablets were evaluated for drug content, hardness, friability, disintegration time (DT), wetting time (WT) and dissolution profiles.

Results and discussion: Phase solubility studies suggested an AL type curve with stability constant (Ks) of 922.52?M?1. Job’s plot revealed 1:2 stoichiometry. All analytical techniques confirmed inclusion complexation. Molecular modeling revealed dispersive van der Waals interaction energy as a major contributor for stabilization of complex. The spray-dried complexes showed higher solubility and faster dissolution compared to plain CLZ. The optimized formulation showed DT of 11.1?±?0.8?s, WT of 8.7?±?0.9?s and almost complete dissolution of CLZ in 15?min.

Conclusion: The prepared tablets with low DT and fast dissolution will prove to be a promising drug delivery system with improved bioavailability and better patient compliance.  相似文献   
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The effect of compatibilization on the morphology, mechanical properties, and dynamic mechanical properties of isotactic polypropylene (IPP)/nylon-6 (Ny-6) binary blends was investigated. Maleic anhydride (MAH) functionalized IPP was used as a compatibilizer in binary blends. The morphological, mechanical, and dynamic mechanical properties of binary and ternary blends were compared. The blends containing IPP-g-MAH showed more regular and finer dispersion of phases, different dynamic properties, and improved mechanical properties due to better adhesion between the two phases. The blends were also characterized for their flow properties and extent of water absorption. The melting peak temperature and percent crystallinity of IPP and Ny-6 phases were decreased in compatibilized blends. © 1996 John Wiley & Sons, Inc.  相似文献   
8.
In the earlier pressure-dependent Raman spectroscopic studies, it has been reported that BaTiO3 undergoes a tetragonal to cubic phase transition above ~ 2 GPa, whereas pressure-dependent X-ray absorption, X-ray diffuse scattering studies and pair distribution function studies have reported the presence of a low-symmetry rhombohedral phase above ~ 2.3 GPa. In this report, we present our pressure-dependent Raman spectroscopic studies on polycrystalline BaTiO3 which shows that it first undergoes a transition from tetragonal to orthorhombic/rhombohedral phase above ~ 2.6 GPa and then finally goes to the cubic phase above 8.4 GPa. Pressure-dependent synchrotron X-ray diffraction (SXRD) studies have also been carried out that provided rate of change of volume as a function of pressure resulting in bulk modulus of 215 ± 9 GPa.  相似文献   
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10.
The present work identifies the basic features of burden movement in a rotary kiln. The cold model study was conducted with iron ore as the feed material to determine the influence of length to diameter ratio (L/D) of a rotary kiln on the filling degree, hold-up, and residence time of the charge. An empirical equation correlating different operating variables has been derived on the basis of the experimental results. The influence of individual parameters under different conditions on the residence time and back spillage has also been evaluated. Formerly Joint Director, Research and Development, TISCO  相似文献   
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