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21.
Alok Kumar Rai N. K. Singh Sang-Kwon Lee K. D. Mandal D. Kumar Om Parkash 《Journal of Materials Science: Materials in Electronics》2011,22(9):1286-1289
Dielectric properties of iron doped CaCu3Ti4O12 (CCTO), viz. CaCu3Ti3.9Fe0.1O12 (CCTFO) prepared by a novel semi-wet route have been investigated. X-ray diffraction of powder sintered at 900 °C show formation of single phase solid solution. Energy dispersive X-ray spectroscopy (EDX) confirmed the presence of CuO rich phase at grain boundaries of CCTFO. Nature of dielectric relaxation observed above room temperature is studied using complex plane impedance analysis and modulus spectroscopy. It has been found that out of the two relaxations reported earlier above room temperature, one occurring at lower temperature is due to grainboundaries interfacial polarization. 相似文献
22.
Sumantra Mandal A. K. Bhaduri V. Subramanya Sarma 《Metallurgical and Materials Transactions A》2011,42(4):1062-1072
Dynamic recrystallization (DRX) behavior in hot deformed (by uniaxial compression in a thermomechanical simulator in the temperatures range 1173 K to 1373 K [900 °C to 1100 °C]) Ti-modified austenitic stainless steel was studied using electron back scatter diffraction. Grain orientation spread with a “cut off” of 1 deg was a suitable criterion to partition dynamically recrystallized grains from the deformed matrix. The extent of DRX increased with strain and temperature, and a completely DRX microstructure with a fine grain size ~4 μm (considering twins as grain boundaries) was obtained in the sample deformed to a strain of 0.8 at 1373 K (1100 °C). The nucleation of new DRX grains occurred by the bulging of the parent grain boundary. The DRX grains were twinned, and a linear relationship was observed between the area fraction of DRX grains and the number fraction of Σ3 boundaries. The deviation from the ideal misorientation of Σ3 boundaries decreased with an increase in the fraction of Σ3 boundaries (as well as the area fraction of DRX) signifying that most Σ3 boundaries are newly nucleated during DRX. The generation of these Σ3 boundaries could account for the formation of annealing twins during DRX. The role of Σ3 twin boundaries on DRX is discussed. 相似文献
23.
Soil Mechanics and Foundation Engineering - The resilience of the Daikai subway station during the Kobe earthquake is taken as a case study of tunnel endurance at various points under different... 相似文献
24.
A series of interpenetrating polymer networks has been prepared from two cellulose derivatives, one of which contains cinnamate groups and the other containing randomly substituted cinnamate and allyl groups. The latter derivative forms a crosslinked network in less than 5 min on exposure to ultraviolet radiation and can be used to make amorphous interpenetrating polymer networks containing 50% by weight loading level of crosslinked vinyl polymers. The syntheses of both derivatives and the thermal properties and film morphologies of their interpenetrating polymer networks are discussed. © 1996 John Wiley & Sons, Inc. 相似文献
25.
Metallurgical and Materials Transactions B - The influence of Mn segregation that occurs during casting on recrystallization kinetics has been explored for a C-Mn automotive steel. A homogenization... 相似文献
26.
De Paramita Mandal Sekhar Bhowmick Partha Chanda Bhabatosh 《Pattern Analysis & Applications》2019,22(4):1341-1359
Pattern Analysis and Applications - Decomposition and representation of electrical circuit drawings to a suitable vector form has widespread applications related to data compression, storage,... 相似文献
27.
Mandal Jyotsna Kumar Mukhopadhyay Somnath 《Innovations in Systems and Software Engineering》2019,15(1):1-1
Innovations in Systems and Software Engineering - 相似文献
28.
Durbadal Mandal Sakti Prasad Ghoshal Anup Kumar Bhattacharjee 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(6):667-680
In this paper the maximum sidelobe level (SLL) reductions without and with central element feeding in various designs of three-ring
concentric circular antenna arrays (CCAA) are examined using a real-coded Evolutionary Programming (EP) to finally determine
the global optimal three-ring CCAA design. Standard real-coded Particle Swarm Optimization (PSO) and real-coded Particle Swarm
Optimization with Constriction Factor and Inertia Weight Approach (PSOCFIWA) are also employed for comparative optimization
but both prove to be suboptimal. This paper assumes non-uniform excitation weights and uniform spacing of excitation elements
in each three-ring CCAA design. Among the various CCAA designs, the design containing central element and 4, 6 and 8 elements
in three successive concentric rings proves to be such global optimal design set with global minimum SLL (−39.66 dB) as determined
by Evolutionary Programming. 相似文献
29.
Swapan Kumar Mandal Rabindra Nath Datta Prasanta Kumar Das Dipak Kumar Basu 《应用聚合物科学杂志》1988,35(4):987-994
The reaction between bis(diisopropyl) thiophosphoryl disulfide (DIPDIS) and silica has been investigated. The study reveals that DIPDIS can be used as a coupling agent for silica. The chemical bond between the silanol groups of silica and DIPDIS has been established through the isolation and characterization of isopropyl alcohol that is eliminated from the reaction. The chemical nature of the bond is also supported by the IR analysis of the reaction products of silica and DIPDIS obtained both in the presence and absence of rubber. From the exploratory studies it is indicated that DIPDIS can also react with NR even during mixing of ingredients. When used with 2-mercaptobenzothiazole (MBT) or N-oxydiethylene-2-benzothiazole sulfenamide (OBTS) in the presence of silica, DIPDIS exhibits notable activation of cure and enhances the torque, modulus, tensile strength, and the scorch safety. 相似文献
30.
Anoop K. Mukhopadhyay Keshaw D. Joshi Arjun Dey Riya Chakraborty Ashok K. Mandal Amit Rav Jiten Ghosh Sandip Bysakh Sampad K. Biswas Satish C. Gupta 《Ceramics International》2011,37(7):2365-2376
Shock recovered samples of a coarse grain (10 μm), high density (>99.9% theoretical) alumina from asymmetric impact tests conducted at 6.5 GPa (e.g. 3.2 times its Hugoniot Elastic Limit) in a single stage gas gun and characterized by X-ray diffractometry, scanning and field emission scanning electron microscopy, and transmission electron microscopy showed prolific presence of reduced crystallite size, higher average microstrain, grain localized micro/nano-scale deformations, micro-cleavages, grain-boundary microcracks, micro-wing crack formation, extensive shear induced deformations and fractures localized at grains, grain boundaries and triple grain junctions, grain localized entanglement of dislocations and their pile up impeded at grain boundaries. A new qualitative model based on micro-shear and micro-twist induced deformation and fracture in single and/or multiple planes in suitably oriented grain and/or grain assembly was developed to explain the experimentally observed damage evolution process. 相似文献