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51.
The stability of mechanical equilibrium of a horizontal layer of conducting fluid in the presence of a magnetic field rotating in a horizontal plane is considered. Both finite field rotation frequencies and the limiting case of high frequencies are investigated. It is shown that the magnetic field stabilizes the equilibrium. The dependence of the critical perturbation wavelength on the field strength is non-monotonic, and with increase in the magnetic field strength the mode of most dangerous perturbations changes from long-to short-wave type. Nonlinear three-dimensional convection regimes are calculated numerically. It is found that at finite supercriticalities and a sufficiently strong magnetic field the rolls and the hexagonal cells may be stable simultaneously.  相似文献   
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A simple technique for introducing iron hydroxide into a highly porous polystyrene matrix is proposed. The resulting composite sorbent showed a high ability to purify air by removing hydrogen sulfide, bad-smelling, and toxic products of decay of natural remains, such as putres-cine, cadaverine, indole, and skatol, as well as organic solvents, such as methanol and benzene.

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New chiral oxazoline-containing phosphoramidite was synthesized and its complex formation with rhodium(i) and palladium(ii) was examined. The new ligand is a highly efficient chiral inductor (ee up to 92%) in palladium-catalyzed asymmetric sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinate.  相似文献   
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The effect of a standing acoustic wave on the development of long-wave convective perturbations in a horizontal layer with thermally insulated boundaries is investigated. The main two-dimensional flow is determined. A nonlinear amplitude equation with spatially-periodic coefficients is derived for investigating the stability of the main flow and secondary convection flows in the neighborhood of the stability threshold. The intensity of the acoustic field is assumed to be low. It is shown that the acoustic action leads to destabilization of the layer. Plane and three-dimensional perturbations are critical at large and small Prandtl numbers, respectively. Nonlinear one-dimensional steady-state solutions of the amplitude equation are obtained and their stability is investigated.  相似文献   
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Periodic regimes of large-scale convection in a two-layer system with a deformable interface are considered. In the limiting case of strong surface tension, an amplitude equation describing the interface deformation is derived. Two-dimensional periodic flow regimes are studied. It is shown that, depending on the governing parameters, both hard and soft excitation of convection is possible. In the presence of heating from above, the finite-amplitude excitation of convection was observed.Translated from Izvestiya Rossiiskoi Academii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, 2004, pp. 7–20. Original Russian Text Copyright © 2004 by Lyubimov and Shklyaev.  相似文献   
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A method was developed for the quantitative analysis of the novel anticancer agent ES-285 (spisulosine; free base) in human, mouse, rat, and dog plasma using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry in order to support pre-clinical and clinical studies with the drug. Sample preparation was carried out by protein precipitation with acetonitrile, containing isotopically labeled (d(3)) ES-285 as internal standard. Aliquots of 10 micro l of the supernatant were injected directly on to an Inertsil ODS-3 column (50 x 2.0 mm i.d., 5 micro m). Elution was carried out using methanol-10 mM ammonium formate (pH 4) in water (80 : 20, v/v) pumped at a flow-rate of 0.2 ml min(-1) with a run time of 8 min. Multiple reaction monitoring chromatograms obtained on an API365 triple-quadrupole mass spectrometer were used for quantification. The lower limit of quantitation (LLOQ) was 10 ng ml(-1) in human, mouse, rat, and dog plasma and the linear dynamic range extended to 500 ng ml(-1). A full validation of the method was performed in human plasma, and partial validations were performed in mouse, rat and dog plasma. Accuracies and precisions were <20% at the LLOQ concentration and <15% for all other concentrations in all matrices. ES-285 was stable during all steps of the assay. Thus far this method has been used successfully to analyze over 500 samples in pre-clinical trials, and will be implemented in the planned clinical phase I studies.  相似文献   
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Russian Chemical Bulletin - Ammonium derivatives of triethanolamine have been effectively used as catalysts for the addition of CO2 to epoxides. The iodine additive was found to exert a positive...  相似文献   
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