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A detailed study has been made of the extraction of indium into chloroform by 1-(2-pyridylazo)-2-naphthol (PAN). The rate of extraction is maximal if the PAN is added to the aqueous phase and is not added as its chloroform solution. The ratio of indium to PAN is 1:1 and the cationic complex can be extracted only if a suitable anion is present, such as acetate or chloride.  相似文献   
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This paper deals with the effect of photobiomodulation (PBM) on Daphnia magna S. and their sensitivity to cadmium sulfate, a known high toxic pollutant. In a first series of experiments, the effect of different He-Ne laser fluences irradiation (range 0.9-4300 mJ cm−2) on the fertility of both parent and filial generations (F1–F3) of the crustacean was studied. It was found that PBM in some cases significantly influenced the fertility of both irradiated crustaceans and their nonirradiated offspring. By selecting two fluences (9 ± 2 mJ cm−2 reducing fertility and 4.3 ± 0.9 J cm−2 increasing it), the effect of these on toxicity of cadmium sulfate was evaluated. These experiments have shown that prior irradiation with low-intensity light of a helium–neon laser with 632.8 nm wavelength can change the sensitivity of aquatic organisms to toxin cadmium sulfate. The degree and direction of changes depend on the toxicant concentration and the irradiation dose.  相似文献   
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Journal of Structural Chemistry - Rhodium nitromonoethylenediamine complexes with compositions K[Rh(en)(NO2)4] (I), (Me4N)[Rh(en)(NO2)4]·2H2O (II), [Rh(en)(H2O)(NO2)3]·H2O (III),...  相似文献   
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Mn site is substituted with closed shell ions (Al, Ga, Ti, Zr and a certain combination of Zr and Al) and also with Fe and Ru ions carrying the magnetic moment (S=5/2 and 2 respectively) at a fixed concentration of 5 at %. Substitution did not change either the crystal symmetry or the oxygen stoichiometry. All substituents were found to suppress both the metal-insulator and ferromagnetic transition temperatures (T p(ρ) and T C, respectively) to varied extents. Two main contributions identified for the suppression are the lattice disorder arising due to difference in the ionic radii between the substituent (r M) and the Mn3+ ion (r Mn 3+) and in the case of the substituents carrying a magnetic moment, the type of magnetic coupling between the substituent and that of the neighboring Mn ion.  相似文献   
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Doklady Mathematics - New kinetic equations are proposed from which the incompressible Euler and Navier–Stokes equations are derived by making an exact substitution. A class of exact...  相似文献   
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Metal-catalyzed CH-functionalization of pyrrole and its derivatives via insertion of CF3-carbene generated from methyl 2-diazo-3,3,3-trifluoropropionate was studied. The reactions are completed within few minutes upon heating in toluene in the presence of 1 mol.% of commercially available copper trifluoroacetylacetonate. These reaction conditions allow simultaneous introduction of trifluoromethyl and methyl carboxylate groups into the aromatic pyrrole ring. Conditions for C(2)-selective monofunctionalization of NH-pyrroles were developed.  相似文献   
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Dihydrolipoamide dehydrogenase from Escherichia coli (LpD) is a bacterial enzyme that is involved in the central metabolism and shared in common between the pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase complexes. In the crystal structure, E. coli LpD is known to exist as a dimer. The present work is focused on analyzing the solution structure of LpD by small-angle X-ray scattering, molecular docking, and analytical ultracentrifugation. It was shown that in solution LpD exists as an equilibrium mixture of a dimer and a tetramer. The presence of oligomeric forms is determined by the multifunctionality of LpD in the cell, in particular, the required stoichiometry in the complexes.  相似文献   
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