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101.
Predrag M. Tekić Jelena B. Rađenović Svetlana S. Popović 《International Journal of Computational Fluid Dynamics》2013,27(9):383-390
In this article, the lattice Boltzmann method is employed in order to explore incompressible fluid flow inside a two-sided lid-driven staggered cavity. Results of the lattice Boltzmann simulation for antiparallel motion of lids are compared with the data from existing literature. For parallel motion of lids, the characteristics of flow pattern for a variety of Re numbers (50–3200) are presented. An asymmetric steady-state flow pattern for parallel motion of lids is obtained. 相似文献
102.
Ljubica R. Dja?anin Miroslav D. Drami?anin Svetlana R. Luki?-Petrovi? Dragoslav M. Petrovi? Marko G. Nikoli? 《Central European Journal of Physics》2012,10(2):519-523
Lithium-indium oxide is a high-density (5.9 g·cm−3), wide band-gap semiconductor with promising applications for scintillating detection of solar neutrinos as well as for efficient
phosphorescence when doped with Er3+ or Sm3+ ions. In this report, we demonstrate visible upconversion emission of Er3+-doped LiInO2 synthesized by a simple solid-state chemistry procedure and discuss mechanisms responsible for pumping the Er3+ ions to upper levels. Intense upconversion emission is observed in the green and red spectral regions under near-infrared
excitation, and it is greatly enhanced by co-doping with Yb3+ ions. We also examined the upconversion intensity change as a function of temperature, and, consequently, possible applications
of this material as a low-temperature sensor. 相似文献
103.
Branko Markoski Ana J. Šetrajčić-Tomić Dragana Rodić Igor J. Šetrajčić Svetlana Pelemiš Jovan P. Šetrajčić 《Optik》2014
The changes of optical properties under boundary presence in molecular crystal nanofilm were theoretically investigated in this work. The dispersion law and states of excitons as well as their space distribution along boundary direction have been determined using adjusted Green's function method and also by combined analytical and numerical calculations. On the basis of real and imaginary part of relative permittivity, both absorption and refraction indices were determined, and the influences of boundary parameters on occurrence of a very selective and strictly discrete absorption were analyzed. 相似文献
104.
BACKGROUND: Immunity against the T cell receptor (TCR) is considered to play a central role in the regulation of experimental allergic encephalomyelitis (EAE), a model system of autoimmune disease characterized by a restricted usage of TCR genes. Methods of specific vaccination against the TCR of pathogenetic T cells have included attenuated T cells and synthetic peptides from the sequence of the TCR. These approaches have led to the concept that anti-idiotypic immunity against antigenic sites of the TCR, which are a key regulatory element in this disease. METHODS: The present study in the Lewis rat used a conventional idiotypic immunization based on antigenized antibodies expressing selected peptide sequences of the Vbeta8.2 TCR (93ASSDSSNTE101 and 39DMGHGLRLIHYSYDVNSTEKG59). RESULTS: The study demonstrates that vaccination with antigenized antibodies markedly attenuates, and in some instances, prevents clinical EAE induced with the encephalitogenic peptide 68GSLPQKSQRSQDENPVVHF88 in complete Freunds' adjuvant (CFA). Antigenized antibodies induced an anti-idiotypic response against the Vbeta8.2 TCR, which was detected by ELISA and flowcytometry. No evidence was obtained of a T cell response against the corresponding Vbeta8.2 TCR peptides. CONCLUSIONS: The results indicate that antigenized antibodies expressing conformationally-constrained TCR peptides are a simple means to induce humoral anti-idiotypic immunity against the TCR and to vaccinate against EAE. The study also suggests the possibility to target idiotypic determinants of TCR borne on pathogenetic T cells to vaccinate against disease. 相似文献
105.
Sergey P. Gromov Svetlana N. Dmitrieva Artem I. Vedernikov Nikolay A. Kurchavov Lyudmila G. Kuz'mina Yuri A. Strelenko Michael V. Alfimov Judith A. K. Howard 《Journal of Physical Organic Chemistry》2009,22(9):823-833
An improved method for the synthesis of formyl derivatives of N‐methylbenzoazacrown ethers is proposed. They are prepared in up to 68% yields over fewer steps and with a much shorter time required for the last step. The stability constants of complexes formed by N‐methylbenzoazacrown ethers and their structural analogs with alkali metal, alkaline‐earth metal and ammonium cations were determined by 1H NMR titration in CD3CN. High stability of complexes of N‐methyl derivatives of benzoazacrown ethers is demonstrated, comparable with or even exceeding the stability of benzocrown‐ether complexes and markedly exceeding the stability of complexes of phenylazacrown ethers with the same macrocycle size. The structures of azacrown ethers and their complexes with Ba(ClO4)2 were studied by X‐ray diffraction. A high degree of pre‐organization of N‐methylbenzoazacrown ethers toward the formation of complexes with metal and ammonium cations was noted, which is due to the clear‐cut pyramidal geometry of the nitrogen atom and the orientation of the lone electron pairs (LEPs) of most heteroatoms towards the centre of the macroheterocycle. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
106.
Svetlana Ya. Jitomirskaya 《Communications in Mathematical Physics》1995,168(3):563-570
We prove that for any >2 and a.e. , the pure point spectrum of the almost Mathieu operator (H())
n
=
n-1
+
n+1
+ cos(2( +n))
n
contains the essential closure
of the spectrum. Corresponding eigenfunctions decay exponentially. The singular continuous component, if it exists, is concentrated on a set of zero measure which is nowhere dense in
. 相似文献
107.
A. I. Korobov M. Yu. Izosimova E. V. Prokhorova 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(1):143-145
The potential to create a remote, contactless, diagnostic method for biological tissues or materials with properties similar to those of biological tissues, so-called phantoms, is studied. The method is based on measurement of local oscillations of the surface of material under study under the action of acoustic and ultrasonic waves. The application of a laser-scanning vibrometer provides a means for visualization oscillations of a biological tissue phantom with model defects in the form of air bubbles, regions with higher density, and laminations, and allows determination of the positions of these defects. 相似文献
108.
Alexander N. Titov Ingrid Bryntse Svetlana G. Titova Nadezhda V. Toporova 《Solid State Ionics》2001,140(3-4):293-300
The reaction between metallic Ag and PbS1.18(TiS2)n, n=1, 2, misfit layer compounds has been investigated by electrochemical technique, X-ray powder analysis and transmission electron microscopy. It was found that silver intercalation is possible only in the compound with n=2. The thermodynamic behavior and location of phase boundaries were studied in the temperature range 400–650 K. DC-conductivity and magnetic-susceptibility measurements were performed, and the data can be interpreted as an appearance of small polarons during silver insertion. 相似文献
109.
110.
Svetlana F. Malysheva Natal’ya A. Belogorlova Nina K. Gusarova Alexander V. Artem’ev Alexander I. Albanov Boris A. Trofimov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1688-1693
Abstract Red phosphorus reacts with allylbenzene in the superbase system KOH-DMSO (130°C, 3 h, Ar) to give a mixture of bis(1-methyl-2-phenylethyl)phosphane (1), bis(1-methyl-2-phenylethyl)phosphane oxide (2), and 1-methyl-2-phenylethylphosphinic acid (3). Secondary phosphane oxide 2 and phosphinic acid 3 have been isolated from this mixture in 35% and 32% yield, respectively. Microwave activation of the reaction (200 W, 30 min) affords secondary phosphane 1 as the main product in 48% yield. GRAPHICAL ABSTRACT 相似文献