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71.
A simple and effective method to measure an electromagnetic wave polarization plane's weak rotations in various media is proposed. The specific features of the polarization plane's rotation amplification for the light reflection and transmission through the absorbing and amplifying isotropic layers are calculated. The amplification effects on an anisotropic and cholesteric liquid crystal (CLC) layers are also considered. In conclusion the question of probable choice of the amplifier's noise/signal ratio is discussed. 相似文献
72.
Shakhbazyan L. G. Babakhanyan A. V. Grigoryan Dzh. V. Kocharyan S. T. 《Russian Journal of General Chemistry》2003,73(10):1608-1610
Anilinium salts containing an allyl-like group together with various functionally substituted receiving groups undergo Stevens rearrangement by the action of sodium carbonate hexahydrate in the absence of a solvent. As a result, both N-methylaniline derivatives and nucleophilic substitution products are formed. 相似文献
73.
Jacob Lasri Preetpaul Devgan Vladimir S. Grigoryan Prem Kumar 《Optics Communications》2004,240(4-6):293-298
We demonstrate a novel, polarization-insensitive scheme for multiwavelength nonreturn-to-zero to return-to-zero format conversion at 10 Gb/s rate with significant timing-jitter suppression and signal-to-noise ratio improvement. The scheme utilizes a self-starting electroabsorption-modulator based optoelectronic oscillator that simultaneously generates a 10 GHz-rate microwave signal and a train of 15 ps-wide optical pulses with 40 fs timing jitter (100–10 MHz range). Under direct optical injection locking of the oscillator with an incoming data stream, we demonstrate the extraction of a high-quality clock that enables in-line format conversion of multiple, synchronized nonreturn-to-zero channels. 相似文献
74.
N. P. Grigoryan 《Russian Journal of Organic Chemistry》2018,54(1):55-61
The reaction of ethyl (2Z)-2-cyano-3-cyclohexylprop-2-enoate with benzylmagnesium chloride, followed by cyclization in the presence of sulfuric acid, provided an efficient method of synthesis of ethyl 1-amino-3-cyclohexyl-3,4-dihydronaphthalene-2-carboxylate which was converted to a number of new heterocyclic systems containing a benzo[h]quinazoline fragment. 相似文献
75.
A. S. Sagiyan A. E. Avetisyan S. M. Djamgaryan L. R. Djilavyan E. A. Gyulumyan S. K. Grigoryan N. A. Kuz'mina S. A. Orlova N. S. Ikonnikov V. S. Larichev V. I. Tararov Yu. N. Belokon 《Russian Chemical Bulletin》1997,46(3):483-486
Asymmetric synthesis of β-N-substituted (S)-α,β-diamino acids was accomplished by Michael addition of amines to the NiII complex of the Schiff base derived from (S)-2-[N-(N′-benzylprolyl)amino]benzophenone (BPB) and dehydroalamine. Diastereoselectivity of the reaction is kinetically and thermodynamically
controlled. The chiral auxiliary reagent, BPB, can be recovered and reused.
Translated fromIzvestiya Akademii Nauk. Serya Khimicheskaya, No. 3, pp. 504–507, March, 1997. 相似文献
76.
The diethyl esters of 2-oxo-1-oxaspiro[4,4]nonan-3,4-dicarboxylic, 2-oxo-1-oxaspiro[4,5]decan-3,4-dicarboxylic and 7,7-di-methyl-1,8-dioxaspiro-[4,5]decan-3,4-dicarboxylic acids (la-c) are transformed by hydrochloric acid into 2-oxo-1-oxa-spiro[4,4]nonan-, 2-oxo-1-oxaspiro-[4,5]decan-, and 7,7-dimethyl-1,8-dioxaspiro[4,5]decan-4-carboxylic acids (Ila-c), which are converted into the acyl chlorides IIIa-c, and the latter into the chloromethyl ketones IVa-c. Reaction of the acyl chlorides of IIa and IIb with thiosemicarbazide gives the acid thiosemicarbazides Va and Vb, which form the triazoles VIa and VIb in potassium hydroxide solution, and the thiadiazoles VIIa an VIIb in sulfuric acid. Reaction of the chloromethyl ketones IVa-c with formamide gives the imidazoles VIIIa-c. The diesters Ia-creatwithbenzylamine to form the N-benzylimides IXa-c. 相似文献
77.
M. B. Ordyan V. S. Grigoryan R. V. Avetisyan Ya. T. Éidus 《Russian Chemical Bulletin》1973,22(2):438-439
Conclusions The methyl esters of branched carboxylic acids containing quaternary and tertiary C atoms in the-position, together with a small amount of the corresponding carboxylic acids, are formed during the hydrocarbomethoxylation of the straight-chain C5-C9 olefins at atmospheric pressure in the presence of concentrated H3PO4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 454–456, February, 1973. 相似文献
78.
79.
Oganesyan N. R. Grigoryan Dzh. V. Babayan L. A. Kocharyan S. T. 《Russian Journal of General Chemistry》2003,73(6):951-956
The example of the rearrangement-cleavage under the action of 25% aqueous potassium hydroxide at 90-92°C of ammonium salts containing both 3-methyl-2-naphthylmethyl and 2-bromoethyl, allyl, methallyl, 2-bromoallyl, 3-phenylallyl, 2-propynyl, or 3-phenylphenyl-2-propynyl groups was used to show that the reaction always involves the aromatic ring of the 3-methyl-2-naphthylmethyl group. Along with rearrangement-cleavage, nucleophilic substitution of the 2-naphthylmethyl group takes place. 相似文献
80.
K. M. Gitis V. N. Kornyshev E. S. Shpiro A. A. Grigoryan G. V. Isagulyants Kh. M. Minachev D. P. Shashkin 《Russian Chemical Bulletin》1989,38(7):1349-1354
1. | Selective hydrogenation of piperylene into n-amylenes (300C) on applied nickel sulfide was studied in the pulsed mode. It was found that NiS/SiO2 is more selective than NiS/Al2O3. |
2. | Treatment of applied NiS with air at 300–500C oxidizes a significant portion of NiS into NiSO4, which gives the catalyst hydroisomerizing properties and permits obtaining up to 44% isoamylenes from piperylene. In contrast to oxidized NiS/SiO2, oxidized NiS/Al2O3 retains hydroisomerizing activity for a much longer time, which is due to the higher resistance of NiSO4 to reduction on Al2O3 than on SiO2. |
3. | The data obtained indicate that reduced nickel atoms are the active sites of selective hydrogenation, while sulfur, sulfide or sulfate, is the surface modifier. |