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Using X-ray topography, the distributions of deformations in the volume of two types of AT-cut quartz resonators of different sizes were obtained on laboratory and synchrotron X-ray sources. The comparison of X-ray topography data and the amplitude–frequency characteristics of the resonators was used to establish a correlation between the deformation patterns and the features of oscillatory processes for the operating modes and their harmonics, as well as for parasitic modes. A connection between vibrations at parasitic modes and their harmonics, which manifest themselves in an amplitude inhomogeneity, and the topology of the resonators has been found. The applied significance of the obtained results for the development and optimization of new designs of piezoelectric elements and the development of their manufacturing technology is pointed out. [ABSTRACT FROM AUTHOR]

A composite anticorrosive coating based on an aluminum-chromium-phosphate binding agent (ACPB) and an aluminum filler has been studied using electrochemical methods. The influence of the factor of polishing of the surface on the protective properties of the coating has been shown. A mechanism for the protection of the coating has been proposed. [ABSTRACT FROM AUTHOR]

The effect of structures of the derivatives of [2-(diphenylphosphorylmethoxy)phenyl]-diphenylphosphine oxide (L1) on the complexation properties toward rare-earth elements (REE) was studied. A new structural analogue of L1, isopropyl 2-(diphenylphosphorylmethoxy)benzoate (L3), was synthesized. The extraction of REE by the carboxylated podand L3 in a 1,1,7-trihydrododecafluoroheptanol—water system with the HNO3 concentration varied in a range from 1 to 6 mol L−1 was studied. The stability constants of the neodymium(iii) and erbium(iii) nitrate complexes with L3 and 1-(methoxydiphenylphosphoryl)-2-diphenylphosphoryl-4-ethylbenzene (L2) and of lutetium(iii) nitrate and chloride complexes with L2 in 1,1,7-trihydrododecafluorheptanol were determined. The properties of the membranes of the ion-selective electrodes based on L1, L2, and L3 toward REE cations were tested. The crystal structures of L3 and [NdL3(NO3)3(DMSO)2] were determined by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The extraction of tetrafluoroboric acid from aqueous solutions to a solution of benzo-15-crown-5 (B15С5, 1 mol L-1) in chloroform is shown to occur due to complexation with the ratio of components HBF4: B15С5 = 1: 1.5. It was revealed by IR spectroscopy that the whole crown ether in the extract is coordinated. The 1: 1 HBF4•В15С5 complex was isolated and characterized using IR spectroscopy and X-ray diffraction analysis. The O(2) and O(4) atoms of the crown ether ring participate in the coordination. [ABSTRACT FROM AUTHOR]

Aiming to find extractants suitable for recovery of cesium from nitric acid solutions with a high sodium content, two types of alkylated derivatives of 18-crown-6 were studied. Derivatives of the first type (five compounds) were prepared by introducing alkyl substituents into the macroring. Derivatives of the second type were prepared by introducing alkyl substituents into phenyl or cyclohexyl fragments of dibenzo-18-crown-6 (DB18C6) and dicyclohexyl-18-crown-6 (DCH18C6) (16 compounds). The alkylated crown ethers exhibit different reactivity depending on the substitution mode. Introduction of two alkyl substituents into the phenyl rings of dibenzo-18-crown-6 allowed preparation of compounds ensuring the Cs/Na separation factor as high as 100 and more. [ABSTRACT FROM AUTHOR]