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61.
62.
Vijay K. Arora Carlos Munera Mahmoud Jaafarian 《Journal of Physics and Chemistry of Solids》1977,38(5):469-475
Thermomagnetic coefficients appropriate to a many-valley model of a semiconductor of the n -Germanium type are evaluated in the framework of the density matrix formalism developed earlier. These coefficients are determined for arbitrary values of the magnetic field, within the effective mass approximation. The phonon-drag contribution is not included in this work. An application is made to the four-ellipsoidal model of n-Ge under the conditions where elastic-acoustic phonon scattering is the predominant mechanism of scattering and the high-temperature limit of the phonon distribution is valid. The thermoelectric power (magneto-Seebeck effect) is found to increase with increasing values of the magnetic field except for a small region of low magnetic field values where it decreases in the longitudinal configuration only. 相似文献
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The effect of size quantization on the conductivity of semimetallic and semiconducting rectangular quantum well wires (QWW) is studied. A semimental-semiconductor transition is predicted to occur at a critical thickness of the wire. For wires of smaller thickness than the critical thickness, semiconducting behavior will occur with the conductivity decreasing exponentially with decreasing transverse dimensions of the wire. That is due to carrier freeze-out because of the increase in effective bandgap resulting from the size quantization. The effect dominates any thickness dependence of the mobility resulting from scattering interactions. 相似文献
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R.P. Pant Manju Arora Balwinder Kaur Vinod Kumar Ashok Kumar 《Journal of magnetism and magnetic materials》2010,322(22):3688-3691
Nanoparticles of CoGdxFe2−xO4 (where x=0.0, 0.1, 0.3, 0.5) series have been prepared by chemical co-precipitation. The effect of Gd3+ ion concentration on crystalline phase, crystallinity, crystallite size, molecular vibrations and magnetic resonance has been investigated in detail. The crystallinity decreases with an increase in Gd3+ ion concentration and changes the structural parameters. The spin lattice relaxation has been correlated with the doping ion concentration. Similarly, the superparamagnetic behavior of these particles has been observed with EPR spectroscopy. 相似文献
68.
Mohan K. Kadalbajoo Puneet Arora 《Numerical Methods for Partial Differential Equations》2010,26(5):1206-1223
The advection‐diffusion equation has a long history as a benchmark for numerical methods. Taylor‐Galerkin methods are used together with the type of splines known as B‐splines to construct the approximation functions over the finite elements for the solution of time‐dependent advection‐diffusion problems. If advection dominates over diffusion, the numerical solution is difficult especially if boundary layers are to be resolved. Known test problems have been studied to demonstrate the accuracy of the method. Numerical results show the behavior of the method with emphasis on treatment of boundary conditions. Taylor‐Galerkin methods have been constructed by using both linear and quadratic B‐spline shape functions. Results shown by the method are found to be in good agreement with the exact solution. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010 相似文献
69.
S. V. Vidwans V. P. Salvi A. A. Rangwala Kuldeep Animesh K. Jain B. M. Arora 《辐射效应与固体损伤》2013,168(2-4):111-119
We have used ion implantation of 30 keV48Ti+ ions into a-Si films at nominal doses of 1020-1021 ions/m2 to fabricate coherent silicide layers. Characterization of these layers and study of their annealing behaviour were carried out using XRD and RBS techniques. We find that the layers are a mixture of Ti5Si4, TiSi, TiSi2 and Si. On annealing at relatively lower temperatures (up to ~ 300° C), predominant silicide phases present in the layer are Ti-rich, such as Ti5Si4 and TiSi. At higher temperatures, the Ti-rich layer has a tendency to consume unreacted Si from the film and to form a predominantly Si-rich silicide layer. A structure of silicon different from the diamond cubic structure is noticed in these implanted layers. 相似文献
70.
In this article, we look beyond convexity and introduce the four new classes of functions, namely, approximate pseudoconvex functions of type I and type II and approximate quasiconvex functions of type I and type II. Suitable examples illustrating the non emptiness of the newly defined classes and distinguishing them from the existing classical notions of pseudoconvexity and quasiconvexity are provided. These newly defined concepts are then employed to establish sufficient optimality conditions for the quasi efficient solutions of a vector optimization problem. 相似文献