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31.
Medha Rele Sudhir Kapoor Shweta Hedge Sergej Naumov Tulsi Mukherjee 《Research on Chemical Intermediates》2006,32(7):637-645
Many photo-physical studies have been reported for the detection of Hg2+ ions. Here we present the effect of Hg
2
2+
ions on the absorption and fluorescence of indole-2-carboxylic acid (I2C). Experimental evidence, supported by density functional
theory B3LYP/LANL2DZ/PCM, for the formation of a I2C-Hg
2
2+
complex, is reported for the first time. It was observed that I2C forms a ground-state complex with Hg
2
2+
ions in a ratio of 3:1. The possibility of I2C to be used as a selective novel chemical sensor for the spectrophotometric
detection of mercurous ions is described. 相似文献
32.
33.
L. P. Kozeeva M. Yu. Kameneva N. V. Podberezskaya I. G. Vasilieva N. V. Kuratieva D. Yu. Naumov V. A. Nadolinnyi V. E. Fedorov 《Journal of Structural Chemistry》2004,45(2):253-261
Cooling a melt of a Bi–Sr–Ca–Cu–O system (Bi:Sr:Ca:Cu = 4:3:3:4 or 2:2:2:4) from 1000°C-1050°C yielded crystals of a new red-colored nonsuperconducting phase, accompanying the superconducting 2212 and 2201 phases. Based on the EPR spectra, it was concluded that copper is univalent in this compound. The new phase has a composition Bi2.2Sr1.6Ca1.3Cu2Ox. The X-ray diffraction pattern has been indexed, and the unit cell parameters of the phase have been determined: space group P2/m, a = 12.93, b = 4.55, c = 10.94 ; = 102.72°. 相似文献
34.
35.
R. N. Ziatdinova V. Yu. Nesterov N. M. Zaripov V. A. Naumov A. R. Burilov 《Journal of Structural Chemistry》1990,31(1):155-158
A. E. Arbuzov Institute of Organic and Physical Chemistry, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 1, pp. 169–173, January–February, 1990. 相似文献
36.
A. S. Romakhin F. M. Palyutin Yu. A. Ignat'ev E. V. Nikitin Yu. M. Kargin I. A. Litvinov V. A. Naumov 《Russian Chemical Bulletin》1990,39(3):585-589
The electrochemical oxidation of hexaethyl triamidophosphite in the absence of nucleophiles specially introduced into the electrolyte was studied by anodic voltamperometry and preparative electrolysis. The reversible one-electron oxidation of the triamidophosphite molecule gives an unstable radical-cation, which reacts with a molecule of the starting compound to give a dimeric radical-cation, whose subsequent oxidation leads to dodecaethylhexaamidobisphosphonium diperchlorate. This product is the first example of an acyclic, doubly charged bisphosphonium cation with a
. The crystal structure of this compound was obtained by x-ray diffraction structure analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 664–669, March, 1990. 相似文献
37.
S. V. Belaya D. Yu. Naumov N. V. Podberezskaya I. G. Vasilieva N. V. Pervukhina 《Journal of Structural Chemistry》2003,44(6):1011-1017
A series of experiments have been carried out to synthesize holmium polysulfides at temperatures from 600 to 840°C and sulfur vapor pressures of (2.1, 6.5, 16.7)á105 Pa. Polysulfide crystals sized up to 2 mm and micron-sized powders were investigated thereafter by powder diffractometry. Powder diffraction patterns were calculated based on our previous X-ray structural data. Characteristic reflections have been revealed for the individual monoclinic and tetragonal phases, and X-ray phase analysis (XRPA) has been performed for all batches of the synthesis. The monoclinic phase is shown to prevail irrespective of the synthetic conditions. The tetragonal phase was found in amounts of up to 10 wt.%. 相似文献
38.
B. A. Arbuzov Z. G. Isaeva M. G. Belyaeva V. V. Ratner O. N. Kataeva I. A. Litvinov V. A. Naumov 《Russian Chemical Bulletin》1992,41(1):117-119
Oxidation of 2-carene by lead tetraacetate in acetic acid afforded p-menth-1(10),2-dien-7-ol, 2-acetyl-6,6-dimethylbicyclo[3.1.0]hexane, p-menth-2-ene-1,7-diol, p-menth-1-ene-3,7-diol, and 2-(m-tolyl)propanol-2.Deceased.A. M. Butlerov Scientific Research Chemical Institute, V. I. Ul'yanov-Lenin Kazan' State University, 420008 Kazan. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 147–150, January, 1992. 相似文献
39.
40.
I.?S.?TerekhovaEmail author a?A.?Yu.?Manakov V.?V.?Feklistov Yu.?A.?Dyadin V.?YU.?Komarov D.?Yu.?Naumov 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(3-4):207-211
X-ray powder diffraction studies were performed of the polyhydrates, formed at positive temperature in swelled grains of carboxylic cation-exchange resins in the form of tetraisoamylammonium (cross-linked tetraisoamylammonium polyacrylates, differing in the degree of cross-linking: 1, 2 and 3%). It was shown that the polyhydrates exist as the crystalline phase under specific conditions, determined earlier by DTA technique. Diffraction patterns of the samples, recorded at the temperature +3 ± 1 °C, indicate that the polyhydrates crystallize in hexagonal symmetry, the unit cell parameters are close to a=12.25 Å, c=12.72 Å and do not depend significantly upon the degree of cross-linking. The suppositions were made concerning the size of hydrate crystallites, formed in the swelled grains of the studied resins.This revised version was published online in July 2005 with a corrected issue number. 相似文献