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961.
Mikolaichuk O. V. Sharoyko V. V. Popova E. A. Protas A. V. Fonin A. V. Anufrikov Yu. A. Malkova A. M. Shmaneva N. T. Ostrovskii V. A. Molchanov O. E. Maistrenko D. N. Semenov K. N. 《Russian Chemical Bulletin》2022,71(5):1050-1056
Russian Chemical Bulletin - ({5-[4,6-Di(aziridin-1-yl)-1,3,5-triazin-2-yl]amino}-2,2-dimethyl-1,3-dioxan-5-yl)-methyl 2-(5-phenyl-2H-tetrazol-2-yl)acetate was synthesized and characterized. The... 相似文献
962.
V. A. Semenov 《Fluid Dynamics》1993,28(5):734-735
The parametric instability of a nonuniformly heated horizontal layer of liquid dielectric with free isothermal boundaries in a transverse electric field is studied analytically. An instability map is obtained. It is shown that instability can develop at some critical electric field strength which depends on the frequency and is several times greater than the critical strength of the constant electric field.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, pp. 184–186, September–October, 1993. 相似文献
963.
N. A. Anfimov I. V. Ershov E. I. Ruzavin S. S. Semenov S. K. Shimarev 《Fluid Dynamics》1993,28(5):714-719
The results of an experimental and theoretical study of the structure of the shock wave and the gas flow behind it are presented, together with data on the duration of the high-temperature working flows, the contact zones and the regions of uniform cold-flow parameters in the large (channel diameter 0.5 m, length 200 m, gas tank diameter 3 m, length 23 m) interchangeable-nozzle shock tube of the Central Scientific Research Institute of Mechanical Engineering.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, pp. 158–165, September–October, 1993. 相似文献
964.
V. V. Panchuk N. O. Rabdano A. A. Goidenko A. V. Grebenyuk S. M. Irkaev V. G. Semenov 《Journal of Analytical Chemistry》2017,72(6):662-670
A possibility of identification of the oxidation state of iron by wavelength dispersive X-ray fluorescence spectroscopy using both the position and intensity of L α and L β spectral lines of iron and by principal component analysis score data obtained by the decomposition of the spectral region corresponding to spectral L-series lines of iron is demonstrated. The application of scores ensures a more reliable identification in comparison with line parameters (position and intensity). Two approaches based on projection on latent structures (PLS) regression for the determination of the concentration of iron in different oxidation states are proposed. The first approach consists in using reference models with compositions similar to those of analyzed samples. In the second approach, PLS regression was build using model spectra obtained from spectra of readily available iron compounds. 相似文献
965.
The 15N NMR magnetic shielding constants (followed by recalculation into chemical shifts) in a representative series of amines were calculated in the framework of the density functional theory. The results were compared with experiment. The accuracy factors of this calculation (functional, basis set, solvent effects, and multistandard) were studied. Taking into account all the above factors leads to a noticeable decrease in the average absolute error in the calculation of the 15N NMR chemical shifts (from 13 to 4 ppm) in a range of their changing in the studies series of compounds of ~60 ppm (which is 6—7% in relative units). 相似文献
966.
V. V. Semenov N. V. Zolotareva B. I. Petrov E. N. Razov G. A. Domrachev 《Doklady Chemistry》2017,475(2):179-183
Reaction of poorly soluble manganese(II) bis(1-hydroxyethylidene)diphosphonate tetrahydrate Mn(H3L)2 · 4H2O with 2-aminoethanol H2NCH2CH2OH in an aqueous solution on heating to 70–80°C causes the initial formation of soluble tris(2-hydroxyethanaminium) manganese(II) bis(1-hydroxyethylidene) diphosphonate Mn(H3L)2 · 3H2NCH2CH2OH · 4H2O, which next disproportionates into poorly soluble 2-hydroxyethanaminium manganese(II) (1-hydroxyethylidene)diphosphonate MnH2L · H2NCH2CH2OH and metal-cation-free coordination polymer of (1-hydroxyethylidene)diphosphonic acid with 2-aminoethanol. Poorly soluble MnH2L · H2NCH2CH2OH can be readily converted into the soluble form by treatment with 2-aminoethanol or 2-amino-2-(hydroxymethyl)propane-1,3-diol H2NC(CH2OH)3. 相似文献
967.
Chaika AN Semenov VN Nazin SS Bozhko SI Murphy S Radican K Shvets IV 《Physical review letters》2007,98(20):206101
We report on scanning tunneling microscopy studies of the Cu(014)-O surface using MnNi tips. Remarkably, the results show a regular apparent doubling of surface atomic rows in the {110} direction. A qualitative explanation of this feature based on tight binding and density functional theory calculations of the electronic structure of the tip is presented. Double imaging of the same atom by different legs of dyz orbital could be the reason for the observed doubling. The orientation of the orbital is determined by the O-Mn crystal field. 相似文献
968.
A. L. Semenov 《Physics of the Solid State》2007,49(12):2303-2306
The photoinduced semiconductor-metal phase transition occurring for a time Δt < 1 ps in the surface layer of vanadium dioxide is studied theoretically. A nonthermal mechanism of instability development is considered. An equation for the order parameter ξ of the photoinduced semiconductor-metal phase transition is derived. It is shown that the transition of the surface layer of VO2 to the metallic state requires irradiation by a laser pulse whose energy density W exceeds a critical value W c. The phase transition is initiated at the surface, after which the interface propagates deep into the sample. The critical energy density W c, the velocity of propagation of the metal-semiconductor interface, the thickness z 0, and the characteristic time Δt of formation of the metal layer are calculated. The theoretical results obtained are in agreement with the experimental data on irradiation of vanadium dioxide single crystals by high-intensity laser pulses. 相似文献
969.
A. L. Semenov 《Physics of the Solid State》2007,49(6):1157-1160
A relationship is obtained for a time τ of a photoinduced semiconductor-metal phase transition of the Peierls type under exposure to an ultrashort laser pulse. It is demonstrated that (i) the time τ increases as the pulse energy density W decreases, and (ii) the phase transition is initiated when the pulse energy density W exceeds a critical value W c . The results obtained are compared with the experiment on irradiation of a vanadium dioxide film in a light field. 相似文献
970.
Morozov N. F. Indeitsev D. A. Muratikov K. L. Semenov B. N. Vavilov D. S. Kudryavtsev A. A. 《Doklady Physics》2021,66(9):269-272
Doklady Physics - In the present article it is shown that the presence of defects in a material for a certain duration of heat exposure leads to the necessity of taking into account the dependence... 相似文献