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51.
52.
Gennady I. Nikishin Emmanuil I. Troyansky Igor V. Svitanko Oleg S. Chizhov 《Tetrahedron letters》1984,25(1):97-98
N-Methylpentanehydroxamic acid (N-methyl-N-pentanoylhydroxylamine) 1 rearranges into N-methyl-O-pentanoylhydroxylamine 2 through spontaneous N→O acyl migration. 相似文献
53.
Margherita Barile Gennady Lyubeznik 《Proceedings of the American Mathematical Society》2005,133(11):3199-3209
We describe a class of toric varieties which are set-theoretic complete intersections only over fields of one positive characteristic .
54.
A cyclotomic polynomial n is said to be of order 3 if n = pqrfor three distinct odd primes p, q, and r. We establish theexistence of an infinite family of such polynomials whose coefficientsdo not exceed 1 in modulus. 2000 Mathematics Subject Classification11B83, 11C08. 相似文献
55.
Ananchenko GS Pojarova M Udachin KA Leek DM Coleman AW Ripmeester JA 《Chemical communications (Cambridge, England)》2006,(4):386-388
In an ethanol/water mixture, the nitroxyl radical TEMPO abstracts a hydrogen atom from a phenolic OH group of the amphiphilic para-hexanoylcalix[4]arene, and the hydroxylamine TEMPOH formed yields a stable inclusion complex with another molecule of the calixarene. 相似文献
56.
Mousavi SH Khanikaev AB Neuner B Avitzour Y Korobkin D Ferro G Shvets G 《Physical review letters》2010,105(17):176803
Highly confined "spoof" surface plasmons (SSPs) are theoretically predicted to exist in a perforated metal film coated with a thin dielectric layer. Strong modes confinement results from the additional waveguiding by the layer. Spectral characteristics, field distribution, and lifetime of these SSPs are tunable by the holes' size and shape. SSPs exist both above and below the light line, offering two classes of applications: "perfect" far-field absorption and efficient emission into guided modes. It is experimentally shown that these plasmonlike modes can turn thin, weakly absorbing semiconductor films into perfect absorbers. 相似文献
57.
Arijit Chakrabarty Gennady Samorodnitsky 《Stochastic Processes and their Applications》2018,128(7):2297-2324
We investigate what happens when an entire sample path of a smooth Gaussian process on a compact interval lies above a high level. Specifically, we determine the precise asymptotic probability of such an event, the extent to which the high level is exceeded, the conditional shape of the process above the high level, and the location of the minimum of the process given that the sample path is above a high level. 相似文献
58.
Nikita A. Kazin Nadezhda S. Demina Roman A. Irgashev Ekaterina F. Zhilina Gennady L. Rusinov 《Tetrahedron》2019,75(33):4686-4696
The effective approaches for regioselective double formylation and acetylation of 5,12-dialkyl-6,7-diaryl-substituted 5,12-dihydroindolo[3,2-a]carbazoles by their treatment with dichloromethyl methyl ether in the presence of SnCl4 or with acetyl chloride in the presence of AlCl3 to afford the 2,9-diformyl or 2,9-diacetyl derivatives, respectively, were developed. Furthermore, new 2,9-bis(2,2-dicyanovinyl) derivatives were synthesized by the Knoevenagel condensation of diformyl-containing substrates with malononitrile, when new 2,9-bis(quinoxaline-2-yl)- and 2,9-bis(benzo[g]quinoxaline-2-yl) derivatives were formed via microwave-promoted oxidation of diacetyl-containing substrates with SeO2 to the corresponding diglyoxals, followed by the reaction of these intermediates with o-phenylendiamine or 2,3-diaminonaphthalene, respectively. The basic optical and electrochemical properties of some 5,12-dihydroindolo[3,2-a]carbazoles were investigated. 相似文献
59.
Gazizov Denis A. Fedotov Victor V. Gorbunov Evgeny B. Ulomskiy Evgeny N. Yeltsov Oleg S. Rusinov Gennady L. Rusinov Vladimir L. 《Chemistry of Heterocyclic Compounds》2019,55(6):573-577
Chemistry of Heterocyclic Compounds - Condensation of aminoazoles with (2E)-(3-morpholin-4-yl)acrylonitrile and 3,3-diethoxypropionitrile was used to synthesize a series of... 相似文献
60.