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11.
Karpov V. M. Platonov V. E. Chuikov I. P. Rybalova T. V. Gatilov Yu. V. Shakirov M. M. 《Russian Journal of Organic Chemistry》2004,40(3):421-425
Reactions of 2-amino-3-(1-imino-2,2,2-trifluoroethyl)hexafluoro-1H-indene with carboxylic acid anhydrides and chlorides afforded 2-alkyl(aryl)-4-trifluoromethyl-5,6,7,8,9,9-hexafluoro-1,3-diazafluorenes. The molecular and crystalline structure of the products was studied by NMR spectroscopy and X-ray diffraction. 5,6,7,8,9,9-Hexafluoro-2-phenyl-4-trifluoromethyl-1,3-diazafluorene in crystal gives rise to infinite ladder chains via -stacking interaction between the benzene ring of one molecule and tetrafluorobenzene fragment of the other. 相似文献
12.
B. Damaskin S. Karpov S. Dyatkina U. Palm M. Salve 《Journal of Electroanalytical Chemistry》1982,136(2):217-227
Theoretical analysis of the double-layer model has been carried out in the presence of the specific adsorption of organic cations accompanied by considerable increase of the inner-layer dimensions. The formulae for calculation of the differential capacity curves of an electrode have been derived. A flat minimum at high negative charges, caused by the diffuse structure of the double layer, has been predicted on the capacity curves. The presence of such minima has been verified experimentally on the mercury and bismuth electrodes. By computer calculation it has been shown that, although. relatively good agreement of the theoretically calculated capacity curves with the experimental curves could he obtained, a physically unrealistic interaction parameter of the specifically adsorbed ions had to be used. As demonstrated, this result is a result of the double-layer model assuming linear dependence of the inner-layer integral capacity of the surface coverage and its independence from the electrode charge. 相似文献
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The review summarizes and systematizes data published over the past decade on the use of aliphatic aldehydes in the synthesis of six- and seven-membered carbo- and heterocycles, bicyclic compounds, and macrocycles. Biological activity and synthetic potential of the resulting compounds were also considered. The data are classed according to the ring type formed. 相似文献
15.
Ilya Kuselman Elena Kardash Emil Bashkansky Francesca Pennecchi Stephen L. R. Ellison Karen Ginsbury Malka Epstein Aleš Fajgelj Yury Karpov 《Accreditation and quality assurance》2013,18(6):459-467
A new technique for quantification of human errors in chemical analysis using expert judgments is described. This technique is based on the house-of-security approach developed recently in the field of safety and security for prevention of terrorist and criminal attacks against an organization. The following relative quantification parameters (expressed in %) are proposed in the technique: (a) likelihood score of human error in a chemical analytical measurement/testing method, (b) severity score of human error for reliability of the test results, (c) importance score of a component of a laboratory quality system, and (d) effectiveness score of the quality system as a whole in preventing/blocking human error. As an example, 34 scenarios of human error in pH measurement of groundwater are discussed and quantified. 相似文献
16.
Bryzgunov M. I. Bubley A. V. Denisov A. P. Goncharov A. D. Parkhomchuk V. V. Panasyuk V. M. Reva V. B. Kremnev N. S. Putmakov A. A. Belikov O. V. Gorchakov K. M. Skorobogatov D. N. Chekavinskiy V. A. Bekhtenev E. A. Zharikov A. A. Karpov G. V. Kondaurov M. N. Gusev I. A. Senkov D. V. 《Physics of Particles and Nuclei Letters》2020,17(4):425-428
Physics of Particles and Nuclei Letters - In order to achieve the design luminosity in the NICA collider, it is planned to equip it with both stochastic and electron cooling. The electron-cooling... 相似文献
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Karpov VI Dianov EM Paramonov VM Medvedkov OI Bubnov MM Semyonov SL Vasiliev SA Protopopov VN Egorova ON Hopin VF Guryanov AN Bachynski MP Clements WR 《Optics letters》1999,24(13):887-889
An all-fiber 1.48-mum generator based on a laser-diode-pumped Yb-doped double-clad laser and a cascaded Raman wavelength converter has been developed. Second-order Raman Stokes radiation was generated in a phosphosilicate-fiber resonator formed by two pairs of Bragg gratings. A slope efficiency of the Raman converter of 48% with respect to the power emitted by the double-clad Yb laser has been achieved. We obtained an output power of 1 W at a slope efficiency of 34% with respect to the laser-diode array power, with a total optical-to-optical efficiency of 23%. 相似文献
19.
Zonov Ya. V. Karpov V. M. Mezhenkova T. V. 《Russian Journal of Organic Chemistry》2019,55(8):1103-1111
Russian Journal of Organic Chemistry - The carbonylation of perfluoro-2-R-benzocyclobutenones (R = F, CF3, C2F5, C6F5) in a CO-SbF5 system is accompanied by transformations of the four-membered... 相似文献
20.
Grigor’ev Arthur A. Kayukov Yakov S. Nikiforova Anastasiya L. Karpov Sergey V. Shchegravina Ekaterina S. Kayukova Olga V. Tafeenko Victor A. 《Chemistry of Heterocyclic Compounds》2019,55(2):167-171
Chemistry of Heterocyclic Compounds - 4-Acyl-2-amino-6-chloropyridine-3,5-dicarbonitriles underwent heterocyclization in the presence of ammonia in aqueous dioxane medium, involving the... 相似文献