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91.
M. A. Surmeneva R. A. Surmenev V. F. Pichugin N. N. Koval’ A. D. Teresov A. A. Ivanova I. Yu. Grubova V. P. Ignatov O. Primak M. Epple 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2013,7(5):944-951
Silicon-containing hydroxyapatite coatings 400–700 nm in thickness are prepared by means of radio-frequency (RF) magnetron sputtering on a heated (to 200°C) titanium substrate chemically etched and treated with a pulsed electron beam. The morphology and phase composition of the coating are studied. The morphology and roughness of the composite “calcium-phosphate coating-titanium substrate” differ depending on the treatment procedure of the substrate before deposition. The scratch test method is used to assess the adhesion strength of the coatings formed at different values of bias potential applied to the substrate. It is observed that the adhesion strength of the coating changes with decreasing crystallite size. 相似文献
92.
93.
Optics and Spectroscopy - The paper presents a brief review of recent works concerning the modeling of X-ray lasers in cluster flows and in nanostructured targets. Calculations of the atomic... 相似文献
94.
M. B. Gazizov S. Yu. Ivanova R. A. Khairullin Yu. S. Kirillina K. S. Gazizova 《Russian Journal of General Chemistry》2018,88(11):2243-2250
A new procedure has been developed for the simultaneous preparation of terephthalaldehyde and 4-(dibromomethyl)benzaldehyde by catalytic debromophosphoryl- and phosphonyloxylation of 1,4-bis- (dibromomethyl)benzene with P(IV) acid methyl esters. The reaction of 4-(dibromomethyl)benzaldehyde with ortho esters in the presence of sulfuric acid gave the corresponding acetals, whereas in the presence of ZnCl2 terephthalaldehyde bis-acetals were formed. 4-(Dibromomethyl)benzaldehyde and its acetal were converted to methyl 4-(dibromomethyl)- and 4-(dimethoxymethyl)benzoates which were phosphorylated by the action of chlorophosphines, as well as by successive treatment with phosphorus(III) chloride and P(III) esters. 相似文献
95.
Transformations of granules based on kaolin and phosphoric acid under the conditions of vapor-phase crystallization at 170°C were studied. Specific features of the individual and cooperative action of a water vapor and a template dipropylamine on the granules were determined. It is shown that the regulation of competing processes of formation of dense non-porous phases (tridymite, cristobalite, berlinite) and microporous crystalline silicoaluminophosphates of structural types ATL and ATN can be carried out by creating transport pores in the volume of the initial granules. The formation of transport pores was provided by using of porogens (hydroxyethyl cellulose and carbon nanospheres) with the subsequent calcination of the granules. The presence of 40- and 60- nm macropores in the porous structure favored intensification of mass-exchange processes occurring within the granules under the vapor-phase crystallization conditions. This led to an increase in the selectivity of crystallization of the materials with crystal structure types AEL and ATN. The morphology of the crystals with the AEL and ATN structure and their chemical composition depend on the porogen used to prepare the starting granules. 相似文献
96.
A. V. Rudnev N. I. Ivanova N. G. Vanifatova T. G. Dzherajan 《Moscow University Chemistry Bulletin》2014,69(4):175-179
The effect of the time of ultrasonic treatment and concentration of aqueous Tween 80 on the stability of calcium hydroxyapatite suspensions was studied. The optimal conditions under which the system becomes stable were found using capillary-zone electrophoresis, dynamic light scattering, and scanning electron microscopy. The possibility of evaluating the system stability was shown based on studying the electrophoretic behavior of particles. 相似文献
97.
Plasma Chemistry and Plasma Processing - The yield of redox reactions (Fe2+ oxidation and Mn7+ reduction in aqueous solutions) under the action of hot plasma radiation in liquid and species formed... 相似文献
98.
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
99.
G. I. Ovchinnikova N. V. Belugina R. V. Gainutdinov E. S. Ivanova V. V. Grebenev A. K. Lashkova A. L. Tolstikhina 《Physics of the Solid State》2016,58(11):2244-2250
A hydrogen-containing ferroelectric triglycine sulfate (TGS) was comprehensively studied with an atomic force microscopy (AFM) and dielectric spectroscopy. The domain structure dynamics was in situ investigated with piezoresponse force microscopy (PFM) during heating and cooling the TGS crystal near phase transition. Relaxation dependencies of domain boundaries general perimeter and domain dimensions were obtained. TGS dielectric spectra measured at the frequency range from 10 to 1011 Hz were analyzed on basis of significant contribution of conductivity into the dielectric response of ferroelectrics and a good agreement with the experimental data was received. It allows us to obtain more information about temperature dynamics of the domain structure. 相似文献
100.