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In this paper, one-parameter families of integer translates of the Gaussian and Lorentz functions are studied. For a Lorentz function, we obtain formulas for the coefficients of the series defining node functions and show that the limit value of node functions is given by a sample function. For systems of translates generated by the Gaussian and Lorentz functions as well as by the node functions related to them, we obtain explicit expressions for the Riesz constants and study the parameter-dependent behavior of these constants. While proving some of the results of this paper, we establish the monotonicity of a special ratio of two Jacobi theta functions, a fact which is of interest in itself. 相似文献
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E. S. Bazhina G. G. Aleksandrov N. N. Efimov E. A. Ugolkova V. V. Minin A. A. Sidorov V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2013,62(4):962-965
The reaction of an aqueous solution of vanadyl sulfate VOSO4·3H2O, butylmalonic acid (H2Bumal = C4H10(COOH)2), and lithium carbonate at pH ~4–5 gave crystals of the complex Li4(VO)2(Bumal)4(H2O)8]·H2O (1). The structure of complex 1 was established by X-ray diffraction analysis. The molecule of complex 1 consists of two mononuclear bischelate dianionic units {VO(Bumal)2(H2O)} linked by four lithium ions to form the hexanuclear heterometallic {V2Li4} structure. The crystals and an ethanolic solution of compound 1 were studied by ESR spectroscopy. 相似文献
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L. D. Popov S. I. Levchenkov I. N. Shcherbakov V. V. Minin G. G. Aleksandrov E. A. Ugolkova V. V. Lukov V. A. Kogan 《Russian Journal of Coordination Chemistry》2013,39(12):849-856
4-Formyl-3-methyl-1-phenylpyrazol-5-one quinolin-2-yl-(H2L1) and benzothiazol-2-ylhydrazones (H2L2) were synthesized and studied. Quantum-chemical modeling of possible tautomers of the hydrazones was performed. Copper(II) complexes of the general formula [Cu(HL)(ROH)]Y (R = CH3, C2H5; Y=NO3, ClO4) were obtained and examined by IR and EPR spectroscopy, magnetochemistry, and X-ray diffraction. Additional coordination through the N atom of the pyrazole ring enables the complex molecules to form zigzag polymer chains linked by intermolecular hydrogen bonds. 相似文献
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A. N. Kozachkova N. V. Tsaryk A. V. Dudko V. I. Pekhnyo V. M. Novotortsev I. L. Eremenko V. V. Minin N. N. Efimov E. A. Ugolkova 《Journal of Structural Chemistry》2013,54(2):315-320
A heterometallic complex of Pd(II)-Cu(II) with 1-aminoethylidene-1,1-diphosphonic (AEDP) acid (C4H22CuN2O16P4Pd) n (I) is synthesized. Single crystals of compound I are obtained; its crystal structure is determined by X-ray crystallography. The crystals are orthorhombic, space group Pbcn, a = 18.366(3) Å, b = 9.7661(17) Å, c = 20.198(4) Å, V = 3622.8(11) Å3, Z = 8, d x = 2.376 g/cm3. The compound crystallizes as a coordination polymer; the square environment of Pd(II) is formed by nitrogen atoms of amino groups and oxygen atoms of phosphonic groups, while at two non-equivalent copper atoms the octahedral environment is formed by oxygen atoms of phosphonic groups and water molecules. The crystal structure of compound I is characterized by the formation of a branched network of hydrogen bonds. Based on the analysis of the temperature dependence of the magnetic susceptibility it is found that for the heterometallic complex of Pd(II)-Cu(II) with AEDP antiferromagnetic interactions between the paramagnetic centers are dominant. 相似文献
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Demin A. M. Kandarakov O. F. Minin A. S. Kuznetsov D. K. Uimin M. A. Shur V. Ya. Belyavsky A. V. Krasnov V. P. 《Russian Chemical Bulletin》2021,70(6):1199-1208
Russian Chemical Bulletin - Peculiar features of the modification of Fe3O4 magnetic nanoparticles (MNPs) obtained by co-precipitation from solutions of FeII and FeIII salts (10-nm MNPs) and by the... 相似文献
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Gekhman A. E. Moiseeva N. I. Minin V. V. Larin G. M. Kovalev Yu. V. Ustynyuk Yu. A. Rosniatovskii V. A. Timokhina E. N. Bozhenko K. V. Moiseev I. I. 《Kinetics and Catalysis》2003,44(1):40-53
In the Mo(VI)/H2O2/H2O system, the relaxation time (T
1) of protons in a water molecule and in a CH3 group decreases 10 to 30 times under conditions of dismutation of H2O2 with the formation of 1O2(1g). It is experimentally found that the overequilibrium concentration of triplet dioxygen cannot be the reason behind a decrease in T
1 in the 1H NMR spectra. Neither can it explain the anomalous line broadening in ESR spectra under conditions of 1O2(1g) formation in the systems V(V)/H2O2/AcOH and Mo(VI)/H2O2/H2O. Ab initio calculations showed that it is principle possible that the 3O4(3·-
g-1g) molecule exists in a snake-like form and is formed by the reaction between 3O2(3·-
g) and 1O2(1g), which is the product of H2O2 decomposition in the systems V(V)/H2O2/AcOH and Mo(IV)/H2O2/H2O. The interaction of 1O2 with the ·OOH radical is exothermic (Q = 2.30 kcal/mol) and leads to the formation of ·OOOOH. It is assumed that the paramagnetic species of type ·OOOOH or 3O4(3
A
1) that is formed in the reaction might be responsible for the spectral effects observed. 相似文献
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L. D. Popov V. V. Tkachev Yu. P. Tupolova S. A. Borodkin G. V. Shilov E. A. Ugolkova O. I. Askalepova A. S. Burlov V. V. Lukov I. N. Shcherbakov S. I. Levchenkov V. V. Minin 《Russian Journal of Inorganic Chemistry》2017,62(7):893-899
o-Tosylaminobenzaldehyde dimethylpyrimidyl hydrazone and its copper(II), nickel(II), and zinc(II) complexesare synthesized and studied. According to the X-ray diffraction data, the zinc(II) complex has the structure of a tetragonal pyramid with the N3O donor ligand environment. According to EPR and magnetochemistry data, the copper(II) complex has a similar structure of the chelate core. In the nickel(II) complex, the solvent molecule completes the coordination core to an octahedron. 相似文献