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911.
Existence of 2D enstrophy cascade in a suitable mathematical setting, and under suitable conditions compatible with 2D turbulence phenomenology, is known both in the Fourier and in the physical scales. The goal of this paper is to show that the same geometric condition preventing the formation of singularities – ${\frac{1}{2}}$ -Hölder coherence of the vorticity direction – coupled with a suitable condition on a modified Kraichnan scale, and under a certain modulation assumption on evolution of the vorticity, leads to existence of 3D enstrophy cascade in physical scales of the flow. 相似文献
912.
Jasmina M. Dimitrić Marković Dragan S. Veselinović Jelisaveta M. Baranac Tanja P. Brdarić 《光谱学快报》2013,46(3):104-115
Complexation of aluminum (III) with cyanidin, a natural anthocyanidin molecule, has been investigated in methanol and buffered solutions of pH 3.0 and 4.0. Electronic absorption spectroscopy was performed to characterize the stoichiometry and stability of the complexes formed. In investigated solvents, aluminum bonded moderately to cyanidin requiring large mole ratios of the components (up to 200) for the access of complexation. Molar ratio plots showed the formation of only one complex with stoichiometry aluminum (III):cyanidin of 1∶1 in both investigated media. Semiempirical calculations, performed in the Austin Model 1 parameterization, enabled the determination of the structural features of free compounds as well as complex structural modifications caused by chelation of Al(III). 相似文献
913.
Raman spectra of the species Hg(SCN)2, [Hg(SCN)3], and [Hg(SCN)4]2- in solution of ten aprotic donor solvents have been investigated in the region of the Hg-S vibration. Observed frequency values of measured band of Hg(SCN)2 and [Hg(SCN)3] in different solutions correlate well with donor strength of the solvents. There is a linearity between Hg-S frequency decreasing and increasing of the interaction of the solvent molecules with the mercury (II) ion in the thiocyanate complexes. No significant frequency changes have be found for [Hg(SCN)4]2-. Evidence based on the frequency shifts and depolarization ratios in various solvents supports the view that the Hg(SCN)2 in solution undergos departure from linearity as a result of increasing solvent coordination to the mercury (II) ion. Almost constant frequencies of Hg-S vibration of [Hg(SCN)4]2- in all investigated solvents suggest a regular tetrahedral structure of the ion in solution having much larger radius than corresponding HgX4 (X=Cl,Br,I) ions. 相似文献
914.
Abstract The emission spectra of isotopic BeO molecules as excited in low-pressure arc have been photographed in the region 300–350 nm at medium dispersion. The bands have been assigned to the c3II ? a3II system. The vibrational numbering was obtained from a study of the vibrational isotope effect. Vibrational constants for involved states are derived from least-squares fits of the measured bandhead wavenumbers. 相似文献
915.
916.
Vojislav G. Avakumović 《Mathematische Zeitschrift》1942,47(1):141-152
Ohne Zusammenfassung 相似文献
917.
Miloš Mladenović 《Monatshefte für Chemie / Chemical Monthly》1932,59(1-2):7-15
Ohne Zusammenfassung 相似文献
918.
919.
Marin Katalinić 《Colloid and polymer science》1934,68(3):372-373
Ohne Zusammenfassung
L. D. Mahajan, Kolloid-Z.65, 20 (1933). 相似文献
920.