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151.
A. B. Ustinov P. I. Kolkov A. A. Nikitin B. A. Kalinikos Y. K. Fetisov G. Srinivasan 《Technical Physics》2011,56(6):821-825
Planar phase shifters fabricated based on ferrite-ferroelectric layered structures are studied experimentally. The structures
served as waveguides for spin-electromagnetic waves, whose phase shift was controlled by both electric and magnetic fields.
The measurements were performed in the magnetic field range from 900 to 2100 Oe, which corresponds to operating frequencies
from 4.0 to 8.5 GHz, with 5- to 20-μm-thick yttrium-iron garnet ferrite films and 200- to 500-μm-thick barium-strontium titanate
ferroelectric plates. It is shown that the phase shift may exceed 180° and is a function of the magnetic and electric fields
and also of the thickness of the ferrite and ferroelectric layers. 相似文献
152.
The European Physical Journal E - 相似文献
153.
C. Ravichandran G. Srinivasan Craig Lennon S. Sivananthan J. Kumar 《Superlattices and Microstructures》2011
Lithium (Li) and magnesium (Mg) co-doped zinc oxide (ZnO) thin films were deposited by sol–gel method using spin coating technique. The films were deposited on glass substrates and annealed at different temperatures. The effects of annealing temperature on the structural, optical and electrical properties of the deposited films were investigated using X-ray diffraction (XRD), Ultraviolet–Visible absorption spectra (UV–VIS), photoluminescence spectra (PL), X-ray photo electron spectroscopy (XPS) and Hall measurements. XRD patterns indicated that the deposited films had a polycrystalline hexagonal wurtzite structure with preferred (0 0 0 2) orientation. All films were found to exhibit a good transparency in the visible range. Analysis of the absorption edge revealed that the optical band gap energies of the films annealed at different temperatures varies between 3.49 eV and 3.69 eV. Room temperature PL spectra of the deposited films annealed at various temperatures consist of a near band edge emission and visible emission due to the electronic defects, which are related to deep level emissions, such as oxide antisite (OZn), interstitial zinc (Zni), interstitial oxygen (Oi) and zinc vacancy (VZn) which are generated during annealing process. The influence of annealing temperature on the chemical state of the dopants in the film was analysed by XPS spectra. Ion beam analysis (Rutherford back scattering) experiments were performed to evaluate the content of Li and Mg in the films. Hall measurements confirmed the p-type nature of the deposited films. 相似文献
154.
Simultaneous velocity and temperature measurements in gaseous flow fields using the VENOM technique 总被引:1,自引:0,他引:1
We present an initial demonstration of simultaneous velocity and temperature mapping in gaseous flow fields using a new nitric oxide planar laser-induced fluorescence-based method. The vibrationally excited NO monitoring (VENOM) technique is an extension of two-component velocimetry using vibrationally excited NO generated from the photodissociation of seeded NO(2) [Appl. Opt. 48, 4414 (2009)], where the two sequential fluorescence images are obtained probing two different rotational states to provide both velocity and temperature maps. Comparisons to computational fluid dynamics simulations show that the initial VENOM measurements provide good velocity and temperature maps in the relatively high-density regions of the flow, where the rms uncertainties are approximately 5% for velocity and 9% for temperature. 相似文献
155.
Kaushik Mukherjee Srinivasan Natesan 《Numerical Methods for Partial Differential Equations》2014,30(6):1931-1960
In this article, we consider a class of singularly perturbed mixed parabolic‐elliptic problems whose solutions possess both boundary and interior layers. To solve these problems, a hybrid numerical scheme is proposed and it is constituted on a special rectangular mesh which consists of a layer resolving piecewise‐uniform Shishkin mesh in the spatial direction and a uniform mesh in the temporal direction. The domain under consideration is partitioned into two subdomains. For the spatial discretization, the proposed scheme is comprised of the classical central difference scheme in the first subdomain and a hybrid finite difference scheme in the second subdomain, whereas the time derivative in the given problem is discretized by the backward‐Euler method. We prove that the method converges uniformly with respect to the perturbation parameter with almost second‐order spatial accuracy in the discrete supremum norm. Numerical results are finally presented to validate the theoretical results.© 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1931–1960, 2014 相似文献
156.
Gopala Krishna Srinivasan 《Expositiones Mathematicae》2013,31(2):151-168
In this paper, we provide a unified approach to a family of integrals of Mellin–Barnes type using distribution theory and Fourier transforms. Interesting features arise in many of the cases which call for the application of pull-backs of distributions via smooth submersive maps defined by Hörmander. We derive by this method the integrals of Hecke and Sonine related to various types of Bessel functions which have found applications in analytic and algebraic number theory. 相似文献
157.
D. A. Filippov T. A. Galkina V. M. Laletin G. Srinivasan 《Physics of the Solid State》2011,53(9):1832-1838
A theory of the inverse magnetoelectric effect in the vicinity of electromechanical resonance in disk-shaped samples is presented.
An expression for the coefficient of the inverse magnetoelectric transformation has been obtained using the effective parameter
method. It has been shown that a sharp increase in the magnitude of the effect occurs at a frequency of electromechanical
resonance, and the resonance frequencies for the direct and inverse magnetoelectric effects are different. The dependences
of the resonance frequencies on the ferrite percentage in ferrite-nickel spinel samples and lead zirconate titanate samples
have been studied experimentally. 相似文献
158.
Time evolution of volume fraction of the minor phase is studied in an alumina-doped sodium borosilicate glass inside the immiscible region. It is shown that such a study permits a distinction between the two mechanisms of phase separation; namely spinodal decomposition and nucleation and growth. For spinodal decomposition, the volume fraction decreases initially, whereas for nucleation and growth, it increases with heat-treatment time. 相似文献
159.
160.
The online version of the original article can be found at 相似文献