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Elizaveta Konstantinova Alexander Pavlikov Alexander Vorontsov Alexandra Efimova Victor Timoshenko Pavel Kashkarov 《physica status solidi (a)》2009,206(6):1330-1332
IR and EPR spectroscopy is used to investigate the effect of adsorption of dry and wet ammonia on the concentration of equilibrium charge carriers in porous silicon layers with various initial types of dopants. It is found by means of IR spectroscopy that only in the presence of water molecules the ammonia adsorption results in an increase in the concentration of free charge carriers in n‐type samples up to a level exceeding 1018 cm–3. In p‐type samples, a nonmonotonic dependence of the charge‐carrier concentration on ammonia pressure is observed. By means of EPR spectroscopy in the atmosphere of wet ammonia the generation of conduction‐band electrons in p‐type silicon nanocrystals and the increase in the electron concentration in n‐type silicon nanocrystals in comparison with the initial level are observed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
43.
V. V. Semenov N. V. Zolotareva B. I. Petrov Yu. A. Efimova G. A. Domrachev 《Russian Journal of Coordination Chemistry》2008,34(10):783-788
Acetylacetone reacts with 3-aminopropyl[tris(trimethylsilyloxy)]silane to give a mixture of the isomers 4-[3′-tris(trimethylsilyloxy)silylpropyl]iminopent-2-en-2-ol (90%) and 4-[3′-tris(trimethylsilyloxy)silylpropyl]aminopent-3-en-2-one (10%). According to 1H and 13C NMR data, both isomers exist in the cis-and trans-forms. Anhydrous europium(III) and erbium(III) tris{4-[3′-tris(trimethylsilyloxy)silylpropyl]iminopent-2-en-2-olates} were obtained from the mixture of the isomers and the corresponding propan-2-olates Eu(OPr i )3 and Er(OPr i )3. The resulting complexes are transparent air-stable liquids that are distillable in vacuo and well soluble in photopolymerizable polyorganosiloxane caoutchoucs and urethane acrylate oligomers. The volatility parameters of the europium(III) complex were studied. 相似文献
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Effect of metal corrosion inhibitors, N-acetylmethylpyridium salts, on the hydrogen charging of 08 KP steel and changes in its plasticity upon its etching in solutions
of 3 M sulfuric acid. Inhibitors more strongly diminishing the fraction of hydrogen atoms diffusing into the steel and preserving
or raising its plasticity as compared with the shipment level were found. 相似文献
47.
T. P. Efimova O. Yu. Ozerova T. A. Novikova I. V. Belik V. M. Berestovitskaya 《Russian Journal of General Chemistry》2013,83(9):1779-1786
The interaction of 1-methyl-1-nitroso-2-nitroguanidine with carboxylic acid hydrazides results in formation of N-(2-nitroguanidino)amides that easily give 3(5)-nitroamino-5(3)-alkyl(aryl)-1,2,4-triazoles under refluxing in aqueous alkaline medium. We have developed a one-pot method to prepare such heterocyclic structures; the synthesis of one of the sample compound has given an example of the method applicability. The compounds structures have been confirmed by UV, IR, 1H, and 13C-{1H} NMR spectroscopy. 相似文献
48.
E. A. Chernyshev Z. V. Belyakova L. K. Knyazeva M. G. Pomerantseva L. A. Efimova 《Russian Chemical Bulletin》1998,47(7):1374-1378
Hydrosilylation of several unsaturated compounds with triethoxysilane in the presence of the Speier catalyst with various
additives influencing the reaction rate and selectivity was studied. The mechanism of hydrosilylation is discussed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1413–1417, July, 1998. 相似文献
49.
Opeida I. A. Efimova I. V. Pomeshchenko A. I. 《Russian Journal of Organic Chemistry》2002,38(11):1689-1690
Russian Journal of Organic Chemistry - 相似文献
50.