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1.
The possibility of using time-resolved vibronic spectroscopy for spectral analysis of mixtures of chemical compounds with similar optical properties, when traditional methods (based on stedy-state spectra) are inefficient, is demonstrated by using the method of computer simulation. The analysis is carried out by the example of molecules of a series of polyenes (butadiene, hexadiene, octatetraene, decapentaene, and decatetraene), their various cis-and trans-rotational isomers, and phenyl-substituted polyenes. Ranges of relative concentrations of molecules similar in their spectral properties, where reliable interpretation of time-resolved spectra of mixtures and both qualitative and quantitative analyses are possible, are determined. The use of computer simulation methods for optimizing full-scale experiments in femtosecond spectroscopy is shown to hold much promise. 相似文献
2.
A. D. Vasiliev A. M. Astakhov M. S. Molokeev L. A. Kruglyakova A. M. Sirotinin R. S. Stepanov 《Journal of Structural Chemistry》2004,45(2):360-364
The structure of 5-nitraminotetrazole lithium salt monohydrate was determined by X-ray diffraction analysis. Crystals are monoclinic, space group P21/c; a = 8.3789(5), b = 10.1872(6), c = 6.6709(5) ; = 106.63(1)°; V = 545.60(98) 3; Z = 4; calc = 1.875 g/cm3. The anion has a planar nitrimine structure with a delocalized negative charge. Each lithium cation (c.n. 5) is bound to three anions and two hydration water molecules. Both oxygen atoms of the nitro groups and the N(3) atom of the tetrazole ring are involved in cation coordination. The geometrical characteristics of the anion are similar to those found for other monosalts of 5-nitraminotetrazole. 相似文献
3.
A. M. Astakhov A. D. Vasiliev M. S. Molokeev L. A. Kruglyakova A. M. Sirotinin R. S. Stepanov 《Journal of Structural Chemistry》2004,45(3):537-540
The structure of 5-nitraminotetrazole sodium salt sesquihydrate was determined by X-ray diffraction. The crystals are monoclinic, space group P21/c;a = 3.551(1) Å, b = 21.834(4) Å, c = 9.075(2) Å; = 110.68(3)°; V = 658.3(2) Å3; Z = 4; calc = 1.807 g/cm3. The anion is planar and has an intramolecular hydrogen bond. The negative charge of the anion is localized on one of the oxygens of the nitro group. The sodium cation (c.n.6) is coordinated by three oxygen atoms of different anions and three oxygens of crystallization water. One of the crystallization water molecules is disordered in the unit cell. The anions are hydrogen-bonded with each other and with crystallization water molecules.Original Russian Text Copyright © 2004 by A. M. Astakhov, A. D. Vasiliev, M. S. Molokeev, L. A. Kruglyakova, A. M. Sirotinin, and R. S. StepanovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 562–565, May–June 2004. 相似文献
4.
Alexander V. Astakhov Kyrill Yu. Suponitsky Victor M. Chernyshev 《Mendeleev Communications》2018,28(4):439-441
An efficient synthesis of 2-amino-1-R-[1,2,4]triazolo[1,5-a]- pyrimidinium or 3-amino-2-R-[1,2,4]triazolo[4,3-a]pyrimidi- nium chloride derivatives by heterocyclization of 3,5-diamino- 1-R-1,2,4-triazoles (R = Alk or Ar) with pentane-2,4-diones was developed. The process is promoted by chlorotrimethyl- silane which plays the dual role of carbonyl-activating agent and water scavenger. 相似文献
5.
Soliev S. B. Astakhov A. V. Pasyukov D. V. Chernyshev V. M. 《Russian Chemical Bulletin》2020,69(4):683-690
Russian Chemical Bulletin - Catalytic activity of nickel(ii) and palladium(ii) N-heterocyclic carbene (NHC) complexes derived from imidazole, benzimidazole, and 1,2,4-triazole was comparatively... 相似文献
6.
7.
Formation of a donor profile in silicon upon simultaneous implantation of phosphorus and sodium ions
V. M. Korol’ V. P. Astakhov S. A. Vedenyapin A. V. Zastavnoi 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(2):358-361
A four-point probe method was used to study, as the layers were removed consecutively, the concentration distribution profiles
of free electrons in high-resistivity p-Si with implanted P+ and Na+ ions. Anodic oxidation was used to remove layers at a depth of less than 1 μm, and polishing at larger depths. It was shown
that the efficiency of diffusion doping of silicon with sodium is determined, to a large extent, by the ratio between the
energies of P+ and Na+ ions. If the conditions are optimal, the efficiency of doping by simultaneous implantation of sodium and phosphorus ions
is better (by a factor of 2.5 on the average) than that of doping with Na+ ions only. 相似文献
8.
9.
Kimel AV Astakhov GV Schott GM Kirilyuk A Yakovlev DR Karczewski G Ossau W Schmidt G Molenkamp LW Rasing T 《Physical review letters》2004,92(23):237203
Static and time-resolved magneto-optical spectra of the ferromagnetic semiconductor (Ga,Mn)As show that a pulsed photoexcitation with a fluence of 10 microJ/cm(2) is equivalent to the application of an external magnetic field of about 1 mT, which relaxes with a decay time of 30 ps. This relaxation is attributed to the spin relaxation of electrons in the conduction band and is found to be not affected by interactions with Mn ions. 相似文献
10.