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51.
3,5-Di(hydroxyalkyl) derivatives of 4-amino-1,2,4-triazole and the corresponding derivatives of 1,2,4-triazole obtained by diazotizing them are converted by reaction with SOCl2 into the hydrochlorides of 4-amino-3,5-di(chloroalkyl)-1,2,4-triazoles and 3,5-di(chloroalkyl)-1, 2,4-triazoles. The dinitrate of 3,5-di(hydroxymethyl)-1,2,4-triazole has been prepared. When the cyanohydrazide of glycolic acid is heated with hydrazine hydrate, 4,5-diamino-3-hydroxymethyl-1, 2,4-triazole is formed. 相似文献
52.
53.
V. A. Nikanorov T. V. Storozhev S. G. Novikov S. V. Sergeev D. V. Zverev 《Russian Chemical Bulletin》1998,47(6):1224-1225
The possibility of redox troponization of a gem-polyhalomethylated semiquinoid system, π-coordinated to a metal atom, was
shown in relation to the reaction of (η5-cyclopentadienyl)(η4-4-menthyl-4-exo-trichloromethylcyclohexa-2,5-dien-1-one)rhodium with Pd(PPh3)4. The reaction occurs with retention of the metal coordination affording a sevenmembered organometallic derivative of the
nonbenzoid aromatic series, namely, (η5-cyclopentadienyl)(η4-4-chloro-5-menthylcyclohepta-2,4,6-trien-1-one)rhodium, whose structure was established by means of elemental analysis, NMR,
and mass-spectral data.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1255–1256, June, 1998. 相似文献
54.
Khlebnikov A. F. Novikov M. S. Kusei E. Yu. Kopf J. Kostikov R. R. 《Russian Journal of Organic Chemistry》2003,39(4):559-573
Esters of (2,2-diaryl-3,3-dichloroaziridin-1-yl)acetic acid prepared from glycine derivatives under alkylation conditions afford esters of 2-[N-alkyl-N-(2,2-diaryl-1-cyanovinyl)amino]-3,3-diarylacrylic acid in 20-40% yield. The reaction resulting in these compounds proceeds through a cascade of 3-chloro-2-azadiene and ylide intermediates. 3-Chloro-2-azadienes originating from (2,2-diaryl-3,3-dichloroaziridin-1-yl)acetates react with primary and secondary amines at the carbon atom of imine group providing ketenimines which undergo ketenimine-nitrile rearrangement or fragmentation. The other bases (KOH, MeONa, DBU) effect dehydrochlorination of the mentioned 3-chloro-2-azadienes giving nitrile-ylides which are trapped by nucleophilic reagents. The 3-chloro-2-azadiene obtained from methyl (2,2-diaryl-3,3-dichloroaziridin-1-yl)acetate and DBU was relatively stable and was isolated as an individual compound. (2,2-diaryl-3,3-dichloroaziridin-1-yl)propionates behave as nonfunctionalized dichloroaziridines. 相似文献
55.
E. S. Kolodeznyi S. S. Rochas A. S. Kurochkin A. V. Babichev I. I. Novikov A. G. Gladyshev L. Ya. Karachinskii D. V. Denisov Yu. K. Bobretsova A. A. Klimov S. A. Blokhin K. O. Voropaev A. S. Ionov 《Optics and Spectroscopy》2018,125(2):238-242
Results of investigation of 1550 nm range stripe semiconductor lasers fabricated from heterostructures with different designs of the gain medium are presented. It is shown that the proposed designs of the gain medium allow obtaining the effective lasing at high level of total optical losses, comparable with the typical optical losses in the vertical-cavity surface-emitting lasers. The evaluation of modal gain in different types of the gain mediummade it possible to estimate the possible frequencies of the small-signal modulation of vertically emitting lasers and proposed the ways to increase them up to 20 GHz or more. 相似文献
56.
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58.
A. A. Andrianov V. A. Andrianov O. O. Novikov 《Theoretical and Mathematical Physics》2013,175(3):735-743
We briefly review the mechanism of fermion localization on a domain wall (“thick brane”) generated by a topologically nontrivial vacuum configuration of scalar fields. We propose an extension of the scalar field coupling to fermions that endows the fermions with an axial mass. In the case of several flavors and fermion generations, this extension can lead to the appearance of the Standard Model Cabibbo-Kobayashi-Maskawa matrix. We also consider a model with two scalar doublets that ensures an additional mechanism of CP-parity violation. 相似文献
59.
The relaxation of the electric current in a metal–nitride–oxide–semiconductor structure has been measured experimentally. The experiment has been compared with the calculation based on the two-band conduction model and the multiphonon mechanism of the ionization of traps. The upper estimate obtained for the recombination cross section from the comparison of the experiment with the calculation is found to be 5 × 10–13 cm2. 相似文献
60.
A. D. Bouravleuv N. V. Sibirev D. V. Beznasyuk N. Lebedeva S. Novikov H. Lipsanen G. E. Cirlin 《Physics of the Solid State》2013,55(11):2229-2233
Arrays of (Ga,Mn)As nanowhiskers have been grown by molecular-beam epitaxy. The scanning electron microscopy study of the surface morphology of the samples has revealed the appearance of mechanical vibrations of individual nanowhiskers. To describe the vibrations, a model has been developed for the determination of the Young’s modulus of (Ga,Mn)As nanowhiskers. 相似文献