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181.
182.
M. Y. Salloum O. S. Grunsky A. A. Man’shina A. S. Tver’yanovich Yu. S. Tver’yanovich 《Russian Chemical Bulletin》2009,58(11):2228-2232
Indirect methods of investigation of composition and defect structures of lithium niobate (LiNbO3) single crystals with different compositions are discussed. The analysis of two methods for the determination of the Li/Nb
ratio in the samples is carried out, viz., the fundamental UV absorption edge and IR vibrational spectra of the OH− group defects. Intrinsic defect concentrations in lithium niobate crystals (lithium vacancies, $
V_{Li^ - }
$
V_{Li^ - }
and defects, $
Nb_{Li^{4 + } }
$
Nb_{Li^{4 + } }
) as a function of the Li/Nb ratio in the samples are given. The results obtained can serve as an effective way of express
non-destructive composition analysis in a mass production of parallel-plane plates. 相似文献
183.
Yoshinari Awaji Hideaki Furukawa Naoya Wada Eddie Kong Peter Chan Ray Man 《Optical and Quantum Electronics》2008,40(5-6):461-466
The WDM flatness easily collapses due to substantial changes in input power, an inherent problem in optical packet communication because of dynamic changes in traffic density. We propose a burst-mode EDFA with a novel configuration based on the concept of a mid-position gain flattening filter (GFF) with overpumping. This configuration can effectively suppress gain transience while maintaining WDM flatness. 相似文献
184.
185.
We derive the evolution equation for probability distributions and characteristic functions of the quantum tomograms associated with the linear and nonlinear evolutions of quantum states.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 142, No. 2, pp. 365–370, February, 2005. 相似文献
186.
We investigate the confinement properties of bounded, nonnegative, compactly supported vortices of axisymmetric incompressible Euler flows without swirl. We show that along one direction of the symmetry axis, its support can grow no faster than O[(t log t)1/2]. The rate at which it approaches the symmetry axis is also estimated. Together with the result of Maffei–Marchioro on the radial growth rate of the support, it is contained in a slowly expanding tubular region. The techniques of the above‐mentioned authors, Iftimie–Lopes–Nussenzveig and Iftimie–Sideris–Gamblin, are used. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
187.
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190.
Sangita Atul Kumar Shikha Sharma Surojeet Sengupta Man Mohan Singh Suprabhat Ray 《Monatshefte für Chemie / Chemical Monthly》2008,139(10):1269-1277
(Mercaptophenyl)naphthylmethane derivatives were synthesized as novel estrogen receptor binding ligands. [4-(Methylsulfonyl)phenyl](naphth-1-yl)ketone
shows a very promising activity towards osteoporosis.
Correspondence: Sangita, Medicinal and Process Chemistry Division, Central Drug Research Institute, Lucknow 226001, India. 相似文献