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51.
D. N. Chausov А. D. Kurilov А. V. Kazak А. I. Smirnova V. К. Velichko E. V. Gevorkyan 《Liquid crystals》2013,40(9):1345-1352
A cholesteric liquid crystal (CLC) – cholesteryl tridecylate (X-20) was doped with nanoparticles of shungite carbon (Sh) to effectively improve some physicochemical properties of the CLC matrix for the further use in electronic devices. The influence of Sh (concentration of 0.005 and 0.02 wt. %) on phase transition temperatures of X-20 was studied. Addition of 0.005 wt. % of Sh shifts phase transition temperatures upward, while the concentration increase to 0.02 wt. % leads to the opposite effect. These data were taken into account during the study of dielectric properties in different phase states. The dielectric properties were studied in the frequency range from 20 Hz to 10 MHz. Only for the system X-20/Sh (0.02 wt. %), dispersion of the dielectric permittivity was observed. The dispersion was caused by the appearance of additional relaxation processes and it was substantially more extended than the classical Debye theory suggests. The results of the research show that the ‘CLC – Sh nanoparticles’ composites can be used as promising materials to increase the efficiency of radio electronics devices. 相似文献
52.
Ionic and Phase Compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 Ferrogarnet Powder Produced by Gel Combustion
Teterin Yu. A. Smirnova M. N. Maslakov K. I. Teterin A. Yu. Kopeva M. A. Nikiforova G. E. Ketsko V. A. 《Doklady Physical Chemistry》2022,503(2):45-49
Doklady Physical Chemistry - The ionic and phase compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 ferrogarnet samples obtained by gel combustion with subsequent vacuum annealing were studied for the first... 相似文献
53.
V. S. Krivobok I. A. Denisov E. N. Mozhevitina S. N. Nikolaev E. E. Onishchenko A. A. Pruchkina A. A. Silina N. A. Smirnova M. A. Chernopitsskii N. I. Shmatov 《Physics of the Solid State》2016,58(5):981-991
Shallow impurity–defect states in undoped Cd1–xZnxTe (x ~ 3–6%) single crystals have been studied using low-temperature photoluminescence measurements. It has been found that the effect exerted by zinc is mainly reduced to a rigid shift of all the specific features associated with the exciton radiation, which made it possible, with a high (~0.3 meV) accuracy, to measure the band gap and the zinc concentration in solid solutions. Hydrogen-like donors with the ground-state energy of ~14 meV and four types of acceptors with average activation energies of 59.3 ± 0.6 meV, 69.6 ± 1.5 meV, 155.8 ± 2.0 meV, and 52.3 ± 0.6 meV have been identified in all the crystals studied. Based on a comparison with the results of the analysis of the impurity background and the data available in the literature on impurity–defect emission in undoped CdTe, the first three acceptors can be assigned to the substitutional impurities NaCd, PTe, and CuCd, respectively. The most shallow acceptor (52.3 ± 0.6 meV) is a complex defect in which there is a nonstandard excited level separated by only 7 meV from the ground level. This level is formed apparently due to the removal of degeneracy, which is characteristic of TD acceptors, by the low-symmetry potential of the complex defect. 相似文献
54.
Smirnova M. N. Kop’eva M. A. Nikiforova G. E. Nipan G. D. Yapryntsev A. D. Petrova K. V. Korotkova N. A. 《Doklady Chemistry》2021,500(2):213-218
Doklady Chemistry - The boundaries of Mg1 – xNixGa2O4 solid solutions (0 ≤ х ≤ 0.5) with a spinel structure synthesized by the gel combustion method,... 相似文献
55.
Rassolov A. V. Ivanov G. A. Bragina G. O. Baeva G. N. Smirnova N. S. Kazakov A. V. Usachev N. Ya. Stakheev A. Yu. 《Kinetics and Catalysis》2021,62(5):641-650
Kinetics and Catalysis - The catalytic performance of a bimetallic RhIn/SiO2 catalyst was studied in the liquid-phase hydrogenation of nitrobenzene. The formation of intermetallic Rh1In1... 相似文献
56.
M. V. Pavlovskaya N. N. Smirnova A. V. Markin D. F. Grishin 《Russian Journal of Applied Chemistry》2014,87(3):324-330
Specific features of radical polymerization of vinyl chloride in the presence of nitroxyl radicals of the imidazoline series (2-methyl-2,3-diphenyl-1,4-diazaspiro[4,5]dec-3-ene-1-oxyl, 2,2,5,5-tetramethyl-4-phenyl-2,5-dihydroimidazole-1-oxyl, 2,2,5-trimethyl-4,5-diphenyl-2,5-dihydroimidazole-1-oxyl) were studied. The possibility of preparing vinyl chloride-styrene block copolymers in the presence of these nitroxyl radicals was demonstrated, suggesting the occurrence of the polymerization by the reversible inhibition mechanism. The molecular-mass characteristics and the glass transition points of the synthesized samples were determined. 相似文献
57.
A. Mdicke D. Demus A. I. Pavluchenko V. V. Titov N. I. Smirnova 《Crystal Research and Technology》1986,21(1):111-115
The phase transitions of 5-n-hexyl-2-[4-n-pentyloxyphenyl]-pyridine were determined by miroscopic and calorimetric investigations. The classification of the smectic modifications was done by investigation of the miscibility relations. Besides the nematic phase smectic phases C, F, G and H were identified. 相似文献
58.
Selective Synthesis of 2,5‐Diformylfuran by Sustainable 4‐acetamido‐TEMPO/Halogen‐Mediated Electrooxidation of 5‐Hydroxymethylfurfural 下载免费PDF全文
Dr. Vera P. Kashparova Dr. Victor A. Klushin Dr. Daria V. Leontyeva Prof. Dr. Nina V. Smirnova Prof. Dr. Victor M. Chernyshev Prof. Dr. Valentine P. Ananikov 《化学:亚洲杂志》2016,11(18):2578-2585
A new method was developed for the selective gram‐scale synthesis of 2,5‐diformylfuran (DFF), which is an important chemical with a high application potential, via oxidation of biomass‐derived 5‐hydroxylmethylfurfural (HMF) catalyzed by 4‐acetylamino‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (4‐AcNH‐TEMPO) in a two‐phase system consisting of a methylene chloride and aqueous solution containing sodium hydrogen carbonate and potassium iodide. The key feature of this method is the generation of the I2 (co‐)oxidant by anodic oxidation of iodide anions during pulse electrolysis. In addition, the electrolyte can be successfully recycled five times while maintaining a 62–65 % yield of DFF. This novel method provides a sustainable pathway for waste‐free production of DFF without the use of metal catalysts and expensive oxidants. An advantage of electrooxidation is utilized in the preparation of demanding chemical. 相似文献
59.
C. Magron Ph. Alfaurt B. Blank L. Daudin T. Eronen M. Gerbaux J. Giovinazzo D. Gorelov S. Grévy H. Guérin J. Hakala V. S. Kolhinen J. Koponen T. Kurtukian Nieto I. D. Moore H. Penttilä I. Pohjalainen J. Reinikainen M. Reponen S. Rinta-Antila M. Roche A. de Roubin N. Smirnova B. Thomas A. Voss L. Xayavong 《The European Physical Journal A - Hadrons and Nuclei》2017,53(4):77
60.
I. E. Smirnova H. Do Thi Thu O. B. Kazakova G. A. Tolstikov O. S. Kukovinets A. N. Lobov K. Yu. Suponitskii 《Russian Journal of Organic Chemistry》2012,48(10):1370-1376
Oxidation of dipterocarpol and its derivatives with ozone gave compounds containing lactone, lactol, alkoxytetrahydrofuran, aldehyde, and methyl ketone fragments in the side chain, as well as 1,2,4-trioxolane fragment in the A ring. The molecular and crystalline structures of dipterocarpol were determined by X-ray analysis. 相似文献