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991.
Stadnyk V. Yo. Matviiv R. B. Shchepanskyi P. A. Rudysh M. Ya. Kogut Z. A. 《Physics of the Solid State》2019,61(11):2130-2133
Physics of the Solid State - The spectral dependences of the absolute piezooptic coefficients of potassium sulfate crystals are studied. It is established that their dispersion dependence is... 相似文献
992.
Technical Physics - An attempt at eliminating the nonspectral matrix effect leading to suppression of the analytic signal intensity at instrument output has been made using an Agilent-7700 mass... 相似文献
993.
A series of new mono- and bis-terpyridine complexes [Mn(tpyOH)Cl2] ( 1 ), [Ni(tpyOH)2](PF6)2 ( 2 ) and [Zn(tpyO)(η1-OCOCH3)(H2O)]⋅3H2O ( 4 ) containing 4′-hydroxy-2,2′:6′,2″-terpyridine (tpyOH) were synthesized and structurally characterized using elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. The reaction of MnCl2 with tpyOH in a mixture of methanol and CH2Cl2 resulted in the formation of 1 . The X-ray crystal structure of 1 reveals that Mn(II) is penta-coordinated by three nitrogen atoms from tpyOH and two Cl− in a slightly distorted trigonal bipyramidal geometry. Complex 2 was also prepared by the reaction of nickel(II) chloride with tpyOH in a methanolic medium in the presence of NH4PF6. Notably, the complex [Ni(tpyOH)(tpyO)]PF6 ( 3 ), obtained during the crystallization of 2 from dichloromethane, was characterized using X-ray crystallography which shows that six nitrogen atoms from terpyridine ligands occupy the coordination sites around the Ni(II) centre in a distorted octahedral geometry with four longer bonds and two shorter Ni N bonds. The reaction of zinc(II) acetate with tpyOH in a mixture of methanol and CH2Cl2 led to the formation of 4 . The crystal structure of 4 reveals the formation of penta-coordinated Zn(II) complex containing three nitrogen atoms from tpyO, a monodentate acetate ligand and one coordinated water molecule. Hirshfeld surface analyses and two-dimensional fingerprint plots show that the main interactions are O…H/H…O contacts in 1 , 3 and 4 . The thermal decomposition reactions of 1 , 2 and 4 were studied using thermogravimetric analysis in detail due to their different structures. The solution luminescence features of 1 , 2 and 4 include high-energy intense π → π* intraligand and low-energy metal-to-ligand charge transfer transitions at room temperature. The calcination of the coordination complexes led to the formation of corresponding nano metal oxides. The products were structurally characterized using infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The average particle size using Scherrer's equation was calculated to be below 50 nm. 相似文献
994.
Shaginyan V. R. Msezane A. Z. Clark J. W. Japaridze G. S. Leevik Y. S. 《JETP Letters》2020,112(10):657-665
JETP Letters - In this brief review, we address manifestations of the T/B scaling behavior of heavy-fermion (HF) compounds, where T and B are the temperature and magnetic field, respectively. Using... 相似文献
995.
Radiophysics and Quantum Electronics - We study experimentally the spectral characteristics of low-frequency current fluctuations in tungsten filaments of lighting lamps in the ranges of... 相似文献
996.
Ivanova N. M. Soboleva E. A. Visurkhanova Ya. A. Muldakhmetov Z. 《Russian Journal of Electrochemistry》2020,56(7):533-543
Russian Journal of Electrochemistry - Copper(II) ferrite is synthesized by the co-precipitation method in the absence and in the presence of polyvinyl alcohol which is followed by thermally... 相似文献
997.
Ukrainian Mathematical Journal - For systems of linear differential equations whose dimension can be lowered, we estimate the growth of meromorphic vector solutions. As an essentially new feature,... 相似文献
998.
Kalyakin L. A. Zvezdin A. K. Gareeva Z. V. 《Theoretical and Mathematical Physics》2020,203(1):457-468
Theoretical and Mathematical Physics - We consider a system of nonlinear autonomous differential equations that describe the orientation of the antiferromagnetic vector in a multiferroic film and... 相似文献
999.
Drah A. Tomić N. Z. Kovačević T. Djokić V. Tomić M. Heinemann R. J. Marinković A. 《Mechanics of Composite Materials》2020,56(2):249-260
Mechanics of Composite Materials - Commercial γ ? Al2O3 particles, Al2O3 n, and synthesized Al2O3 doped with iron oxide (Al2O3 Fe) were used as reinforcements to enhance the toughness of... 相似文献
1000.
Experimental Mechanics - Background: Experimental modelling techniques are still rare for composite structures under complex thermal environments. Objective: In this paper, by taking a... 相似文献