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61.
Yuliya S. Rozhkova Irina V. Plekhanova Alexey A. Gorbunov Olga G. Stryapunina Evgeny N. Chulakov Victor P. Krasnov Marina A. Ezhikova Mikhail I. Kodess Pavel A. Slepukhin Yurii V. Shklyaev 《Tetrahedron letters》2019,60(11):768-772
A new approach for the synthesis of functionalized racemic 3,4-dihydroferroceno[c]pyridines via the Ritter reaction of 2-methyl-1-ferrocenylpropan-1-ol with nitriles in the presence of methansulfonic acid was developed. The scope and limitations of the reaction were evaluated. Selected racemic 3,4-dihydroferroceno[c]pyridines were successfully separated by preparative HPLC on a Chiralcel OD-H column. The absolute configuration of the enantiomers was determined by X-ray crystal structure analysis. 相似文献
62.
Root E. V. Krasnov P. O. Kukushkin A. A. Suboch G. A. Tovbis M. S. 《Russian Journal of Organic Chemistry》2019,55(7):991-994
Russian Journal of Organic Chemistry - Completely substituted p-nitrosophenols were synthesized by cyclocondensation of dimethyl 3-oxopentanedioate with 2-(hydroxyimino)-1-pyridylbutane-1,3-diones.... 相似文献
63.
Krasnov I Diddens I Hauptmann N Helms G Ogurreck M Seydel T Funari SS Müller M 《Physical review letters》2008,100(4):048104
Using an in situ combination of tensile tests and x-ray diffraction, we have determined the mechanical properties of both the crystalline and the disordered phase of the biological nanocomposite silk by adapting a model from linear viscoelastic theory to the semicrystalline morphology of silk. We observe a strong interplay between morphology and mechanical properties. Silk's high extensibility results principally from the disordered phase; however, the crystals are also elastically deformed. 相似文献
64.
Krasnov K 《Physical review letters》2008,100(8):081102
We show that the constraint algebra of Ashtekar's Hamiltonian formulation of general relativity can be nontrivially deformed by allowing the cosmological constant to become an arbitrary function of the (Weyl) curvature. Our result implies that there is not one but infinitely many (parametrized by an arbitrary function) four-dimensional generally covariant local gravity theories propagating 2 degrees of freedom. 相似文献
65.
Musiyak V. V. Nizova I. A. Matveeva T. V. Levit G. L. Krasnov V. P. Charushin V. N. 《Russian Journal of Organic Chemistry》2019,55(6):762-770
Russian Journal of Organic Chemistry - New conjugates of purine and 2-aminopurine with several α- and ω-amino acids have been synthesized following two approaches based on the... 相似文献
66.
The variation in the spectrum of an infrasonic signal emitted by a point source during its propagation from Earth’s surface to ionospheric altitudes and its effect on the ionosphere are considered from model calculations. 相似文献
67.
Gruzdev D. A. Ustinova V. O. Levit G. L. Ol’shevskaya V. A. Krasnov V. P. 《Russian Journal of Organic Chemistry》2018,54(10):1579-1582
Russian Journal of Organic Chemistry - New (S)-homocysteine derivatives containing a meta-carborane fragment were synthesized. m-Carboranyl-(S)-homocysteine sulfoxide was obtained as a mixture of... 相似文献
68.
Zakharov AV Shlykov SA Bumbina NV Danilova EA Krasnov AV Islyaikin MK Girichev GV 《Chemical communications (Cambridge, England)》2008,(30):3573-3575
The molecular structure of a macrocycle with a 24-membered ring, a thiadiazole-containing expanded heteroazaporphyrinoid, has been, for the first time, directly characterised by a synchronous gas electron diffraction and mass spectrometric experiment and DFT calculations; the molecule has the equilibrium structure of C(3h) symmetry with a planar macrocycle. 相似文献
69.
Scandium(Magnesium)-containing bismuth titanates with the pyrochlore structure have been synthesized for the first time. Their homogeneity range has been determined by means of X-ray diffraction analysis and scanning electronic microscopy. Scandium and magnesium distribution over the cationic positions has been studied. Electrophysical properties of single-phase compounds have been studied. The total conductivity of the compounds is a function of magnesium (scandium) and bismuth concentrations. 相似文献
70.
E. A. Azizov S. S. Ananyev V. A. Belyakov E. N. Bondarchuk A. A. Voronova A. A. Golikov P. R. Goncharov A. Yu. Dnestrovskij E. R. Zapretilina D. P. Ivanov A. A. Kavin I. V. Kedrov A. V. Klischenko B. N. Kolbasov S. V. Krasnov A. I. Krylov V. A. Krylov E. G. Kuzmin B. V. Kuteev A. N. Labusov V. E. Lukash I. I. Maximova S. Yu. Medvedev A. B. Mineev V. P. Muratov V. S. Petrov I. Yu. Rodin V. Yu. Sergeev A. V. Spitsyn V. N. Tanchuk V. A. Trofimov R. R. Khayrutdinov M. V. Khokhlov Yu. S. Shpanskiy 《Physics of Atomic Nuclei》2016,79(7):1125-1136
The level of knowledge accumulated to date in the physics and technologies of controlled thermonuclear fusion (CTF) makes it possible to begin designing fusion—fission hybrid systems that would involve a fusion neutron source (FNS) and which would admit employment for the production of fissile materials and for the transmutation of spent nuclear fuel. Modern Russian strategies for CTF development plan the construction to 2023 of tokamak-based demonstration hybrid FNS for implementing steady-state plasma burning, testing hybrid blankets, and evolving nuclear technologies. Work on designing the DEMO-FNS facility is still in its infancy. The Efremov Institute began designing its magnet system and vacuum chamber, while the Kurchatov Institute developed plasma-physics design aspects and determined basic parameters of the facility. The major radius of the plasma in the DEMO-FNS facility is R = 2.75 m, while its minor radius is a = 1 m; the plasma elongation is k 95 = 2. The fusion power is P FUS = 40 MW. The toroidal magnetic field on the plasma-filament axis is B t0 = 5 T. The plasma current is I p = 5 MA. The application of superconductors in the magnet system permits drastically reducing the power consumed by its magnets but requires arranging a thick radiation shield between the plasma and magnet system. The central solenoid, toroidal-field coils, and poloidal-field coils are manufactured from, respectively, Nb3Sn, NbTi and Nb3Sn, and NbTi. The vacuum chamber is a double-wall vessel. The space between the walls manufactured from 316L austenitic steel is filled with an iron—water radiation shield (70% of stainless steel and 30% of water). 相似文献