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1.
Zwitterionic salts of 2-methoxy-4-amino-6-dinitromethyl-1,3,5-triazines were synthesized. The structure of the compounds and the site of nitrogen protonation in the 1,3,5-triazine ring were established based on IR and 1H NMR spectra and on the data of X-ray diffraction analysis. 相似文献
2.
B. S. Fedorov M. A. Fadeev A. A. Gidaspov E. A. Kosareva V. V. Bakharev 《Chemistry of Heterocyclic Compounds》2005,41(2):228-234
The aziridation of 2-R-4,6-bis(trinitromethyl)-1,3,5-triazines containing electron-donor substituents has been studied. It was found that the corresponding 4-azido-2-dialkylamino-6-trinitromethyl-1,3,5-triazines are formed when R = NMe2, NEt2. When R = O–NMe4
+ a novel reaction route was discovered leading to the tetramethylammonium salt of 5-polynitromethyltetrazolo[1,5-a]-1,3,5-triazin-7-one which is formed as a result of azido-tetrazole and lactim-lactam tautomeric conversion. Denitration of this salt at the trinitromethyl group occurs with retention of the tetrazolo-1,3,5-triazine structure. An X-ray analysis was carried out for the denitration product which was the dipotassium salt of 5-dinitromethyltetrazolo[1,5-a]-1,3,5-triazin-7-one.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 259–266, February, 2005. 相似文献
3.
V. V. Bakharev A. A. Gidaspov E. V. Kachanovskaya 《Russian Journal of Organic Chemistry》2007,43(3):454-457
Reactions of 2,4,6-trichloro-1,3,5-triazine with trinitromethane salts in the presence of phenol and substituted phenols gave previously unknown 2,4-diaryloxy-6-trinitromethyl-1,3,5-triazines. Their yields strongly depend on the nature and position of substituent in the benzene ring of phenol. 相似文献
4.
I. G. Kuleyev I. I. Kuleyev S. M. Bakharev 《Bulletin of the Russian Academy of Sciences: Physics》2014,78(9):905-907
The anisotropy and temperature dependences of thermal conductivity for silicon nanowires with diameters higher than 50 nm is investigated using the Callaway three-mode model. Contributions to the thermal conductivity from the boundary and bulk mechanisms of phonon scattering are calculated at room temperature. The relationship between the thermal conductivity and nanowire diameter is analyzed in symmetrical directions and at room temperature. 相似文献
5.
Phonon pulse propagation in cubic crystals with different elastic energy anisotropy types is considered. A closed analytical expression is derived for the phonon flux enhancement factor. The features of its dependences on the isoenergetic surface curvature types are analyzed for all acoustic modes and anisotropy parameter values and signs. 相似文献
6.
7.
O. N. Bakharev N. Zelders H. B. Brom A. Schnepf H. Schnöckel L. Jos de Jongh 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):101-104
We present
69,71Ga-NMR experiments on
microcrystalline samples of the recently discovered
supramolecular compound Ga
84
[
N
(
SiMe
3
)
2
]
20
Li
6
Br
2
(
thf
)
20
.
2
toluene, which is composed of
ligand-coordinated Ga84 metal clusters,
packed together in a fully ordered crystalline matrix. The
compound is highly conducting and even shows superconductivity
below T
c
~ 7.2 K. Our preliminary
results between 10-300 K show a metallic-like behavior: the
nuclear spin-lattice relaxation rate T
1
-1
follows the Korringa law
69
(
T
1
T
)
-1
= 0.36 s
-1
K
-1
, but with a relaxation rate approximately three
times smaller than in bulk -Ga
metal. No quantum-size effects are observed, the Korringa law
being followed down to 10 K, whereas the quantum-gaps for
individual clusters should amount to ~
10
3
K. These results therefore suggest a transport process based on
intermolecular charge transfer, similar as in alkali-doped
fullerenes and silicon-clathrates. 相似文献
8.
A. A. Gidaspov V. V. Bakharev B. S. Fedorov M. A. Fadeev N. P. Konovalova 《Russian Journal of Applied Chemistry》2009,82(10):1816-1820
An approach to the synthesis of water-soluble chlorodinitromethyl-1,3,5-triazines was developed. For this purpose, a diamine
bound to the 1,3,5-triazine cycle and capable to form hydrochloride salts on chlorination is introduced in a molecule. 相似文献
9.
10.
F. L. Bakharev 《Mathematical Notes》2006,79(3-4):314-326
We study the relationship between the Banach—Mazur distance and the modified Banach—Mazur distance. We sharpen the Szarek theorem on the construction of invariant norms with specific properties and construct extremally distant normed spaces with norms invariant under groups of automorphisms of small cardinality. We prove that the trivial upper bound for the Banach—Mazur distance obtained in terms of the modified Banach—Mazur distance is order-sharp. 相似文献