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991.
1.IntroductionWeconsideranextensivesystemofthefamiliarLotka-Volterrasysteminwhichthepopulationshaveself-inhibit(i.e.,withtheadditionofdampingterm)thatcanbemodeledbytheequationswherexandyrepresentthepreydensityandpredatordensityrespectively.Thespecifi... 相似文献
992.
Tamara I. Vakulskaya Lyudmila I. Larina Nadezhda I. Protsuk Valentin A. Lopyrev 《Magnetic resonance in chemistry : MRC》2009,47(9):716-719
The non‐degenerate tautomers of 3‐nitro‐1,2,4‐triazole‐5‐one (NTO) radical anions were investigated for the first time by an ESR method during electrochemical reduction of NTO in an aprotic medium. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
993.
We consider Toeplitz operators over the discrete half plane with generating functions admitting discontinuities of special kind which we call homogenous ones. The main results are the criteria of invertibility and one‐sided invertibility of such operators. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
R.D. Wiersma J.G.S. Lok S. Kraus W. Dietsche K. von Klitzing D. Schuh M. Bichler H.-P. Tranitz W. Wegscheider 《Physica E: Low-dimensional Systems and Nanostructures》2006,34(1-2):16
We observe the total filling factor νT=1 exciton condensate in independently contacted bilayer two-dimensional electron systems in samples with minute tunnel coupling. At balanced electron densities in the layers, we find for both drag and counter-flow current configurations, thermally activated transport with a monotonic increase of the activation energy for d/ℓB<1.65 with activation energies up to 0.4 K. In the imbalanced system the activation energies show a striking asymmetry around the balance point, implying that the gap to charge excitations is considerably different in the separate layers that form the bilayer condensate. This indicates that the measured activation energy is neither the binding energy of the excitons, nor their condensation energy. 相似文献
995.
An improved hybrid method is introduced in this paper as a numerical method to reconstruct the scatterer by far-field pattern for just one incident direction with unknown physical properties of the scatterer. The improved hybrid method inherits the idea of the hybrid method by Kress and Serranho which is a combination of Newton and decomposition method, and it improves the hybrid method by introducing a general boundary condition. The numerical experiments show the feasibility of this method. 相似文献
996.
The synthesis of 3-benzylflavone derivatives was efficiently performed in a one-pot method using substituted 2-hydroxy-acetophenone and appropriate benzaldehydes in the presence of pyrrolidine and ethanol. The distinct features of this methodology include simple procedure, easy purification, and good yields. 相似文献
997.
An efficient one-pot procedure for the synthesis of 2-ethoxycarbonyl indoles from commercially available materials has been developed. The one-step procedure involves in situ formation of the hydrazones from phenylhydrazine hydrochloride and ethyl pyruvate in the presence of bismuth nitrate followed by Fischer cyclization in polyphosphoric acid and ethanol. This method is efficient and simple. 相似文献
998.
Here we report a novel Baker yeast catalyzed one pot cyclocondensation, performed at room temperature in ethanol for obtaining high yields of polyfunctionalized pyridines, 2-amino-4-aryl-3,5-dicyano-6-phenylthiopyridines. The developed protocol obeys certain green principles and is scalable and cost effective. 相似文献
999.
A. I. Zadorin 《Computational Mathematics and Mathematical Physics》2008,48(9):1634-1645
Linear and quadratic spline interpolation methods for a one-variable function with a boundary-layer component are examined. It is shown that the interpolation method for such a function leads to considerable errors when applied on a uniform mesh. The error of linear and quadratic spline interpolations on meshes that are refined in the boundary layer is estimated. Numerical results are presented. 相似文献
1000.