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21.
Mark I. Povolotskii Alexander B. Rozhenko Vitalii V. Polovinko Alexander N. Chernega 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):617-620
Abstract Conjugation effects in various phosphabutadienes are considered. 相似文献
22.
An NMR-relaxation study of the effect of albumin on aggregation of magnetic iron oxide nanoparticles
Ya. Yu. Marchenko B. P. Nikolaev A. N. Shishkin L. Yu. Yakovleva 《Colloid Journal》2013,75(2):185-190
The dependence of the aggregation of magnetic iron oxide nanoparticles in aqueous suspensions under the action of human serum albumin is analyzed based on the data of proton magnetic relaxation. It is shown that albumin adsorption on magnetic nanoparticles gives rise to the formation of a protein corona and clusters of magnetic nanoparticles, decreasing the aggregation stability of the suspension in a 7.1-T magnetic field. Clustering of magnetic iron oxide nanoparticles enhances the relaxation efficiency of magnetic suspensions during NMR measurements. 相似文献
23.
Anatoliy Marchenko Georgyi KoidanAnastasiya Hurieva Aleksandr SavateevAleksandr Kostyuk 《Tetrahedron letters》2013
A direct synthetic approach to C-phosphanyl-N,N-dialkyl-N′-aryl(alkyl)-formamidines was developed. It was shown that phosphorylation of the formamidines proceeds at the nitrogen atom affording N-phosphanylformamidinium salts. Upon deprotonation, these salts gave C-phosphanylformamidines via formation of carbenes followed by a 1,2-phosphorus shift. 相似文献
24.
Kolos Nadiia N. Marchenko Kateryna I. Chechina Nataliia V. Buravov Alexander V. Omelchenko Irina V. 《Chemistry of Heterocyclic Compounds》2021,57(12):1181-1186
Chemistry of Heterocyclic Compounds - A series of functionalized 4,5,6,7-tetrahydroindol-4-one derivatives containing a residue derived from β-dicarbonyl compound at position 3 were prepared... 相似文献
25.
Yu. V. Bogachev Ya. Yu. Marchenko A. V. Nikitina B. P. Nikolaev 《Applied magnetic resonance》2020,51(2):117-127
The investigations of nuclear magnetic resonance (NMR) relaxation of protons in aqueous solution and 2% agar–agar gel in the presence of magnetic nanoparticles were performed. To identify the effect of magnetic nanoparticles on the contrast of magnetic resonance images, the dependences of the MR signal intensity on the parameters of the two pulse radio-frequency (RF) sequences (spin-echo, gradient-echo) most commonly used in MRI for different values of the magnetic nanoparticle (MNP) concentration were simulated and analyzed. Recommendations for choosing the optimal values of pulse RF sequence parameters for MR imaging (MRI) in the presence of MNPs are formulated. MRI studies of phantom samples with 2% agar–agar gel containing MNPs have been performed for choosing the fast pulse RF sequence which shows the greatest contrast effect on MR images. A program for modeling magnetic resonance tomograms and determination of optimal values of pulse RF sequence parameters to achieve the best contrast of magnetic resonance images is developed. This program allows to reduce the time of MRI studies, to assess the possibility of using MNPs for contrast of MR images and to simulate the MR image in the presence of magnetic nanoparticles at the planning stage of procedures in MR-guided theranostics. 相似文献
26.
A. D. Chernyshov V. V. Goryainov A. N. Marchenko 《Thermophysics and Aeromechanics》2016,23(2):237-245
The approximate analytic solution of the problem of temperature field in a rectangular plate with an internal temperature- dependent source is obtained by the method of fast expansions. The critical value of a parameter characterizing heat release, which fundamentally affects the analytic solution form, is found. The maximum solution error is shown to amount to 0.02 at the consideration of the first three terms of the Fourier series in fast expansion. Temperature fields are presented, and an analysis of the influence of the plate sizes and the heat release magnitude on their formation is given. Recommendations on the plate shape choice are given. 相似文献
27.
V. A. Marchenko 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(7):867-870
Experimental realization of the hysteresis-free mode of vanadium reactive magnetron sputtering in Ar-O2 mixtures made it possible to perform detailed measurements of the discharge current-voltage characteristics for the first time. They appeared to be not smooth, as predicted by the existing model of reactive sputtering, but having a kink. The experimental data can be interpreted on the assumption that the target surface is oxidized at a depth not less than two monolayers at low ion current densities. 相似文献
28.
R.V. Ryabova Yu.A. Bykovsky V.A. Elkhov A.I. Larkin V.L. Potapov L.N. Gnatiuk M.L. Gurari S.N. Marchenko 《Optics Communications》1976,18(3):406-409
New photographic materials for recording the radiation of injection lasers (λ=840 nm) with a sensitivity of ?10-4 J/sm2 and a resolution of 4300 lines/mm, and photographic materials for recording the radiation in the region of 1060 nm with a sensitivity of ?10-4 J/sm2 and a resolution of 1000 lines/mm are described. 相似文献
29.
30.
Marchenko AV Vedernikov AN Dye DF Pink M Zaleski JM Caulton KG 《Inorganic chemistry》2004,43(1):351-360
The reaction of equimolar NO with the 16 electron molecule RuHCl(CO)L(2) (L = P(i)Pr(3)) proceeds, via a radical adduct RuHCl(CO)(NO) L(2), onward to form RuCl(NO)(CO)L(2) (X-ray structure determination) and RuHCl(HNO)(CO)L(2), in a 1:1 mole ratio. The HNO ligand, bound by N and trans to hydride, is rapidly degraded by excess NO. The osmium complex behaves analogously, but the adduct has a higher formation constant, permitting determination of its IR spectrum; both MHCl(CO)(NO)L(2) radicals are characterized by EPR spectroscopy, and DFT calculations on the Ru system show it to have a "half-bent" Ru-N-O unit with the spin density mainly on nitrogen. DFT (PBE) energies rule out certain possible mechanistic steps for forming the two products. A survey of the literature leads to the hypothesis that NO should generally be considered as a (neutral) Lewis base (2-electron donor) when it binds to a 16 electron complex which is resistant to oxidation or reduction, and that the resulting N-centered radical has a M-N-O angle of approximately 140 degrees, which distinguishes it from NO(-) (bent at <140 degrees ) and from NO(+) (>170 degrees ). 相似文献