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61.
Yu. I. Latyshev A. P. Orlov A. Yu. Latyshev T. L. Wade M. Konczykowski P. Monceau 《JETP Letters》2010,90(9):608-611
The Aharonov-Bohm effect on multiwall carbon nanotubes has been studied under conditions of resistance with decreasing temperature
as an inverse power function, which precede strong carrier localization. A periodic contribution with a period of 18 T corresponding
to the magnetic flux quantum ħc/e per nanotube cross section has been revealed in the longitudinal magnetoresistance. The result points to the possibility
of the ballistic motion of the carriers over the sample perimeter under conditions close to their strong localization in the
longitudinal direction. 相似文献
62.
T. V. Beryozkina N. N. Kolos V. I. Musatov V. D. Orlov 《Russian Chemical Bulletin》2006,55(6):1056-1059
3,4-Dihydrobenzo-1,4-oxazin-2-ones were obtained from the corresponding β-aroylacrylic acids and 2-aminophenols. With 2-amino-4(5)-nitrophenols,
stable intermediate β-amino adducts (4-aryl-4-oxobutyric acid derivatives) were isolated.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1018–1021, June, 2006. 相似文献
63.
V. V. Turovtsev M. Yu. Orlov R. V. Turovtsev Yu. D. Orlov 《Russian Journal of General Chemistry》2014,84(1):9-15
Internal rotation in the C·H2(CH2) n NO2 (n ≤ 7) type radicals has been studied. 44 potential functions of the internal rotation, V(φ), have been calculated taking advantage of the B3LYP/6-311++(3df,3pd) and MP2/6-311++(3df,3pd) methods. The trends observed in the series of parameters characterizing the internal rotation have been explained in view of the electron clouds conjugation, the inductive effect of the end groups, the gauche effect, and the rotation tops interaction. The coefficients of V(φ) have been shown to depend predominantly on the nearest surrounding of the rotation axis. Based on this, the generalized functions, V av(φ), have been developed, their coefficients being dependent exclusively on the rotating bond position. Such functions are convenient for molecular modeling applications. 相似文献
64.
N. N. Kolos V. D. Orlov E. K. Slobodina E. Yu. Yur'eva S. P. Korshunov Zyong van Tué 《Chemistry of Heterocyclic Compounds》1992,28(2):222-227
1,2,4-Triazolo[3,4-b]-1,3,4-thiadiazines, hydrazones, and -thio adducts were obtained by reactions of 4-amino-3-mercapto-1,2,4-triazole with -bromoacetophenones, aldehydes, and ,-unsaturated ketones. Conditions that promote the cyclocondensation of the -thio adducts to the previously undescribed 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazepines were found. The chemical and spectral properties of the compounds obtained are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 267–272, February, 1992. 相似文献
65.
Victoria V. Lipson Irina V. Ignatenko Sergey M. Desenko Svetlana V. Shishkina Oleg V. Shishkin Sergey A. Komykhov Natalya V. Logvinenko Valery D. Orlov Herbert Meier 《Journal of heterocyclic chemistry》2003,40(6):1081-1086
The reaction of 5,7‐diphenyl‐4,7‐dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidine ( 1 ) with α,β‐unsaturated carbonyl compounds 2a‐f led to the formation of the alkylated heterocycles 3a‐f (Figure 1). However, the reaction of 5‐methyl‐7‐phenyl‐4,7‐dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidine ( 5 ) with 2a‐c yielded under the same conditions the triazolo[5,1‐b]quinazolines 6a‐c (Figure 3). In this case, the alkylation is followed by a cyclocondensation. The structure elucidation of the products is based on ir, ms, 1H and 13C nmr measurements and on an X‐ray diffraction study. 相似文献
66.
N. N. Veniaminov S. A. Khovavko S. A. Voronov S. L. Orlov L. A. Azarov S. Yu. Arkhipov T. N. Evdokimov 《Journal of Analytical Chemistry》2003,58(4):355-360
The elemental and isotopic composition of the core material of a hard-core projectile that had fallen onto the ground was studied by secondary-ion mass spectrometry, alpha and gamma spectrometry, X-ray photoelectron spectroscopy, and scanning electron microscopy with X-ray microanalysis. The environmental aspect of the use of depleted uranium ammunition in Yugoslavia is discussed. 相似文献
67.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 999–1000, July, 1990. 相似文献
68.
S. M. Desenko V. D. Orlov V. V. Lipson O. V. Shishkin K. A. Potekhin Yu. T. Struchkov 《Chemistry of Heterocyclic Compounds》1993,29(1):95-99
Condensation of 5-amino-3-methylpyrazole with chalcone or dypnone gives aromatic substituted 6,7-dihydropyrazolo[1,5-a]pyrimidines which undergo air oxidation. An x-ray structure for 2-methyl-6-hydroxy-5,7-diphenyl-6,7-dihydropyrazolo[1,5-a]pyrimidine is reported.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 109–114, January, 1993. 相似文献
69.
V. Yu. Orlov L. E. Gusel'nikov N. S. Nametkin R. L. Ushakova 《Journal of mass spectrometry : JMS》1972,6(3):309-316
The mass spectra of 1,1-dimethyl-1-silacyclobutane (I—as reported by Cherniak et al.),6, 1,1-dimethyl-1-germacyclobutane (II), 1,1,2,2-tetramethyl-1,2-disilacyclopentane (III) and 1,1,2,2-tetramethyl-1,2-digermacyclopentane (IV) are compared and some correlations between electron-impact fragmentation and thermal decomposition are derived. The mass spectra of the germanium compounds with respect to the silicone compounds are enriched by light fragment ions and exhibit lower intensities of odd-electron ions. The composition of some ions and apparently of neutral fragments coincides with that of the unstable intermediates which are suggested in the thermal decomposition mechanism of some related compounds. The loss of C2H4 is more characteristic under electron-impact as well as in thermal decomposition of Si-compounds, while C3H6 is preferable eliminated by the Ge-compounds. 相似文献
70.