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51.
A. A. Vasil��ev M. I. Struchkova A. B. Sheremetev F. S. Levinson R. V. Varganov K. A. Lyssenko 《Russian Chemical Bulletin》2011,60(11):2306-2314
The palladium-catalyzed cross-coupling reactions of 3-[bromo(het)aryl]furazans and bromobenzofurazans with arylboronic acids afford target biaryls in good yields. 3-Bromo-4-phenylfurazan containing a bromine atom in the furazan ring undergoes decomposition under the reaction conditions. 相似文献
52.
E. V. Tret’yakov V. G. Vasil’ev A. S. Bogomyakov G. V. Romanenko M. V. Fedin I. S. Antipin S. E. Solov’eva A. I. Konovalov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2013,62(2):543-547
A reaction of calix[4]arene tetraaldehyde with 2,3-bis(hydroxyamino)-2,3-dimethylbutane in DMF resulted in the corresponding 1,3-dihydroxyimidazolidine tetraadduct, whose oxidation gave a calix[4]arene (1,3-alternate) bearing four nitronyl nitroxyl-containing substituents at the upper rim. 相似文献
53.
I. A. Khotina A. I. Kovalev N. S. Kushakova M. A. Babushkina Yu. V. Vasil’ev A. S. Peregudov 《Russian Chemical Bulletin》2013,62(10):2234-2244
A series of model cyclotrimers was studied by NMR spectroscopy using 2D COSY, HSQC, and HMBC correlations to establish the structures of branched oligophenylenes, whose branching center is the 1,3,5-triphenyl-substituted benzene ring. 相似文献
54.
I. S. Vasil’chenko I. G. Borodkina A. S. Burlov N. V. Karpova G. M. Abakarov K. A. Lyssenko G. S. Borodkin I. E. Uflyand A. D. Garnovskii V. I. Minkin 《Russian Chemical Bulletin》2013,62(8):1809-1814
Bis-imines of 2,2′-diaminodiphenylditelluride and 2-tosylamino (9a) and 2-hydroxybenzaldehyde (9b) were prepared and studied by X-ray diffraction, heteronuclear (1H, 13C, 15N, and 125Te) magnetic resonance, and quantum chemical calculations (Pbe1pbe/DGDZVP). According to the X-ray diffraction data, compound 9b in the crystal phase has nonsymmetrical structure: one of the tellurium atoms forms hypervalent bonding with the adjacent oxygen atom, while the second one is not involved in such interaction. The NMR study showed the symmetric molecular structure of imines 9a,b in DMSO-d6 with the tellurium atoms interacting hypervalently with the C=N nitrogen atoms. 相似文献
55.
56.
N. I. Kiselev D. A. Velikanov S. B. Korchagina E. A. Petrakovskaya A. D. Vasil’ev L. A. Solov’ev D. A. Balaev O. A. Bayukov I. A. Denisov S. S. Tsegel’nik E. V. Eremin D. A. Znak K. A. Shaikhutdinov A. A. Shubin N. P. Shestakov N. V. Volkov S. K. Gordeev P. I. Belobrov 《Russian Journal of General Chemistry》2013,83(11):2173-2181
The electrical and magnetic properties of the nanodiamond composites comprising nanodiamond, pyrolytic carbon, and nanosized pores were studied. The composites are p-type semiconductors and their resistance decreases by 12 orders of magnitude as the pyrocarbon-to-diamond ratio γ increases from 0 to 80 wt %. Evidence for paramagnetic properties of the nanodiamond composites was obtained. The observed properties are explained by increased concentration of surface Tamm states. The paramagnetic properties are explained in terms of the electron spins localized on the nanodiamond surface in the composite. 相似文献
57.
A. Yu. Vasil’kov I. P. Suzdalev Yu. V. Maksimov L. N. Nikitin A. V. Naumkin S. S. Abramchuk E. M. Tolstopyatov P. N. Grakovich 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(6):985-991
A method for synthesizing iron-containing nanocomposite based on fibroporous polytetrafluoroethylene (PTFE) is described. Fibroporous PTFE obtained under the radiation of a CO2 laser on block PTFE is modified in supercritical carbon dioxide (sc CO2) to form micro- and nanoporous structures. Porous fluoropolymer is treated with a solution of bis(toluene)iron(0) obtained by metal-vapor synthesis (MVS). The composition and structure of iron-containing fluoropolymer is studied by transmission electron microscopy and X-ray photoelectron and Mössbauer spectroscopy. Fe nanoparticles with an average size of 9 nm, consisting of ~30% FeO and ~70% Fe3+, are registered in the sample. Fe0 nanoparticles are stabilized in fluoropolymer pores and are coated with nanoparticles of nonstoichiometric iron oxides that have superparamagnetic properties. 相似文献
58.
Kolyamshin O. A. Mitrasov Yu. N. Danilov V. A. Vasil’ev A. N. 《Russian Journal of General Chemistry》2021,91(8):1459-1465
Russian Journal of General Chemistry - Reaction of 5,5-dimethyl-3-(2-chloroethyl)- and 5,5-diphenyl-3-(2-bromoethyl)- hydantoins with potassium 4-aminobenzoate in dimethylformamide in the presence... 相似文献
59.
D. N. Vtyurina A. N. Romanov K. S. Zaramenskikh M. N. Vasil’eva Z. T. Fattakhova L. A. Trusov P. A. Loiko V. N. Korchak 《Russian Journal of Physical Chemistry B, Focus on Physics》2016,10(2):211-214
The properties of bismuth-containing luminescent materials prepared by impregnating a porous glass with an aqueous solution of bismuth and aluminum salts followed by thermal treatment are studied. The formation of a variety of bismuth-containing centers luminescent in the near infrared range of the spectrum is revealed, one of which is the Bi+ monocation. At high temperatures, along with it, bismuth-containing cluster-type luminescent centers are apparently formed. 相似文献
60.
L. Khusravbekov E. V. Charnaya S. D. Vasil’kov I. K. Rakhimov M. I. Salakhutdinov A. Kholov 《Physics of the Solid State》2007,49(3):516-518
This paper reports on the results of acoustic investigations of a NaBi(MoO4)2 crystal in the temperature range from 20 to 70°C. The temperature dependences of the velocity of longitudinal ultrasonic waves propagating along the crystallographic axes z and x are measured at a frequency of 4 MHz. The results obtained demonstrate that a structural phase transition occurs in the NaBi(MoO4)2 crystal at a temperature of 309 K. The experimental findings are consistent with the assumption that the observed phase transition is either a second-order ferroelastic transition or a first-order ferroelastic transition that is very close to being a second-order phase transition. 相似文献