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91.
92.
Detailed structural analysis of the X-Ray diffraction pattern of La0.9Gd0.1FeO3 (LGFO) synthesized via the solid state reaction reveals distorted perovskite structure. Magnetization studies show a characteristic of weak ferromagnetism which is believed to be induced by canted anti-ferromagnetically coupled spins. When explored in a wide temperature and frequency range, AC electrical properties reveal interesting relaxation mechanisms. LGFO exhibits relatively high dielectric permittivity (ε′~4×103) close to room temperature. Temperature dependent magneto-dielectric response appears (magnetodielectric ~−5.5%) even at low magnetic field ~5 kOe. Attractive electrical, magnetic and magnetoelectric properties of the present LGFO at relatively higher temperature makes it a very promising material for application in devices. 相似文献
93.
Mn2+ doped In2S3–SiO2 nanocomposite thin films were synthesized by sol-gel technique. The films were annealed in air at different temperatures (473–623 K) and characterized by optical, microstructural and electron spin resonance (ESR) study. Optical transmittance study revealed the manifestation of quantum size effect while ESR indicated the presence of manganese in indium sulphide as dispersed dopant rather than manganese cluster. 相似文献
94.
95.
Variation of thermoelectric power with thickness of the vacuum evaporated PbTe films has been investigated. The films were deposited on mica, glass, quartz and LiF substrates, under identical conditions. Attempts have been made to derive a relation which represents the variation of thermoelectric power with thickness of the film. The temperature variation of thermoelectric power has also bsen studied. 相似文献
96.
Classical and quantum theories of radiation damping in ferromagnetic and antiferromagnetic resonance
Both classical and quantum theories of radiation damping in ferromagnetic and antiferromagnetic resonance relaxation are given. Effects of demagnetization and anisotropy, that is, of elliptical classical precession, are included. In the classical theory a phenomenological approach to ferromagnetic resonance relaxation by means of the Landau-Lifshitz equation is also presented. In the quantum theory, the magnon-photon interaction Hamiltonian is derived, and the radiation-damped linewidth is obtained by computing the transition matrix element and also the one-magnon self energy. As noted long ago by Einstein, each photon is emitted in a random but specific direction, and only on average does the quantum radiation pattern reproduce the classical. To first order, however, this reproduction is shown to be exact, correcting a recent calculation by Shrivastava. 相似文献
97.
Karabi Paul T. K. Datta K. S. Chaudhuri A. K. Pal 《The Journal of the Operational Research Society》1996,47(8):1029-1036
The article investigates a deterministic inventory system with two-component demand rate. The demand rate is stock-dependent down to a certain level and then constant. Shortages are allowed and are fully backlogged. The storage space is assumed to be limited. A flowchart is provided to solve a general system. To study the effects of changes in the system parameters on the average net profit a sensitivity analysis has been performed. 相似文献
98.
99.
Using the Landau theory of phase transitions it has been shown that for a second order phase transition Ω/kBTc ? 0.01. and its isomorphs 4Ω/J1 ? 1 and for a first order transition Ω/kBTc ? 0.01. 相似文献
100.
C. Basu K. Goswami S. Chaudhuri A. Choudhury 《Journal of Physics and Chemistry of Solids》1981,42(6):527-528
Lattice imperfections were produced in KCl crystals by a thermal process. The heat treated specimen was irradiated with 50 KeV electrons and the corresponding range of electrons in the crystal has been estimated. It was found that the electron range in the crystal depends upon the temperature of heat treatment, being a decreasing function of this temperature up to about 625 K, above which it becomes an increasing function. This anomaly has been explained in terms of dissolution of vacancies through dislocation loops. 相似文献