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71.
B. Prasanna Lakshmi V. Rajagopal Reddy V. Janardhanam M. Siva Pratap Reddy Jung-Hee Lee 《Applied Physics A: Materials Science & Processing》2013,113(3):713-722
We report on the effect of an annealing temperature on the electrical properties of Au/Ta2O5/n-GaN metal–insulator–semiconductor (MIS) structure by current–voltage (I–V) and capacitance–voltage (C–V) measurements. The measured Schottky barrier height (Φ bo) and ideality factor n values of the as-deposited Au/Ta2O5/n-GaN MIS structure are 0.93 eV (I–V) and 1.19. The barrier height (BH) increases to 1.03 eV and ideality factor decreases to 1.13 upon annealing at 500 °C for 1 min under nitrogen ambient. When the contact is annealed at 600 °C, the barrier height decreases and the ideality factor increases to 0.99 eV and 1.15. The barrier heights obtained from the C–V measurements are higher than those obtained from I–V measurements, and this indicates the existence of spatial inhomogeneity at the interface. Cheung’s functions are also used to calculate the barrier height (Φ bo), ideality factor (n), and series resistance (R s ) of the Au/Ta2O5/n-GaN MIS structure. Investigations reveal that the Schottky emission is the dominant mechanism and the Poole–Frenkel emission occurs only in the high voltage region. The energy distribution of interface states is determined from the forward bias I–V characteristics by taking into account the bias dependence of the effective barrier height. It is observed that the density value of interface states for the annealed samples with interfacial layer is lower than that of the density value of interface states of the as-deposited sample. 相似文献
72.
The addition of TMSCN to ketones catalyzed by dispersed NbF5 gave corresponding cyanohydrin trimethylsilylethers with excellent yield (>90%). Cyano transfer occurs within 30 min at room temperature in the presence of 1 mol% of NbF5 under solvent‐free conditions. These conditions are extremely mild, simple, and tolerate various functional groups. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
73.
K. R. Rajagopal 《Theoretical and Computational Fluid Dynamics》1992,3(4):185-206
Few boundary-value problems in fluid mechanics can match the attention that has been accorded to the flow of fluids, Newtonian and non-Newtonian, between parallel rotating disks rotating about a common axis or about distinct axes. An interesting feature which has been recently observed is the existence of solutions that are not axially symmetric even in the case of flow due to the rotation of disks about a common axis. In this article we review the recent efforts that have been expended in the study of both symmetric and asymmetric solutions in the case of both the classical linearly viscous fluid and viscoelastic fluids.The support of the Air Force Office of Scientific Research is gratefully acknowledged. 相似文献
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A. K. Rajagopal 《Proceedings Mathematical Sciences》1973,78(1):13-24
Three problems are posed and their solutions (ranging from complete to partial) described. They are (i) the Hydrogen atom in an intense magnetic field; (ii) the thermodynamics of one-dimensional chain of continuous spins in an external magnetic field interactingvia Heisenberg interaction; and (iii) the pair correlation function in an interactingmaariys electron system. The relevance of these problems and their solution and various aspects of physics are stressed. 相似文献
77.
B. S. Maruthiprasad M. N. Sastri S. Rajagopal K. Seshan K. R. Krishnamurthy T. S. R. Prasada Rao 《Journal of Chemical Sciences》1988,100(6):459-462
The preparation of a novel nickel trihydroxy isocyanate, along with its distinguishing physicochemical characteristics has
been reported for the first time. 相似文献
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Zusammenfassung Da chelatisierte Hydroxylgruppen in kondensierten Polyhydroxypyronen einen Boracetatkomplex bilden, während andere Hydroxylgruppen im gleichen Molekül normale Acetylierung erleiden, und da aus diesem Komplex die Hydroxylgruppe leicht zurückgewonnen und mittels aktiven Silberoxids und Methyljodids alkyliert werden kann, war es möglich, 1,3-Dihydroxyxanthon selektiv zum 1-Methoxy-3-hydroxyxanthon zu alkylieren. Dessen Konstitution wurde durch Äthylierung zum 3-Äthoxyderivat bewiesen. Letzteres wurde unabhängig davon auch auf anderem Wege synthetisiert.Aus der Dissertation vonG. S. Puranik, Karnatak-Universität 相似文献