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1.
Low-lying energy states of the [Fe3S4]0 cluster have been calculated by taking into account the double exchange, superexchange and vibronic interaction. It was found that the adiabatic potential of the excited state withS=0 corresponds to the full delocalization of the “excess” charge. From the analysis of experimental data of Mössbauer spectroscopy and the temperature dependence of the magnetic susceptibility the double exchange parametert≥4000 cm?1 and the vibronic interaction parameter λ2/2k cm?1 have been estimated. 相似文献
2.
3.
A cooperative defect-deformation (DD) mechanism is developed for the nucleation of the quasi-monodisperse ensemble of nanoparticles in the low-temperature deposition of Ga atoms in the presence of laser radiation. A comparison with experiment is carried out, and a good agreement between the theoretical and experimental results has been obtained. In particular, in accordance with the DD model, it has been found that the arrangement of nanoparticles is characterized by a latent hexagonal order, and their shape is quasi-hexagonal. It has been shown that the characteristics of the deposited ensemble of nanoparticles can be controlled with the use of an anisotropic deformation. 相似文献
4.
A.V. Eremin E.V. Gurentsov M. Hofmann B.F. Kock C. Schulz 《Applied physics. B, Lasers and optics》2006,83(3):449-454
Time-resolved laser-induced incandescence (TR-LII) was applied for the determination of particle sizes during carbon-particle formation from supersaturated atomic carbon vapor that was generated by laser photolysis of carbon suboxide (C3O2) at room temperature. Thus, the solid carbon particles were formed under hydrogen-free conditions. The TR-LII technique was used for in situ size measurement of growing carbon particles and samples of final particles were analyzed by transmission electron microscopy (TEM). It was found that the particles grow to a final size of 4–12 nm within 0.02–1 ms. The properties of the obtained particles depend on the initial conditions in the reaction volume, i.e. concentration of carbon suboxide, pressure and type of gas diluter, photolysis wavelength, and laser pulse energy. The comparison of TR-LII and TEM particle sizing results yields information about the effective thermal energy accommodation coefficients for He, Ar, CO, and C3O2 molecules on carbon particles. PACS 61.46.Df; 07.60.-j; 78.70.-g 相似文献
5.
T. N. Ermolaeva E. S. Dergunova E. N. Kalmykova S. A. Eremin 《Journal of Analytical Chemistry》2006,61(6):609-613
A piezoelectric flow immunosensor for the rapid determination of nonylphenol in aqueous solutions was developed. An aminophenol-protein conjugate (4-AP-GA-BSA) immobilized on the presilanized surface of a silver electrode was used as a bioreceptor coating of the sensor. The effects of the nature and concentration of monoclonal and polyclonal antibodies on the analytical signal of the sensors were studied; the activity of immunoreagents was evaluated based on the binding constants K b. The cross reactions of various phenols with antibodies were studied and the cross reaction percentages were found. A procedure for the flow-injection determination of nonylphenol in liquid media was developed using a piezoelectric immunosensor as a detector. The calibration graph was linear over the concentration range 1–20 ng/mL; the detection limit for nonylphenol was 0.8 ng/mL. 相似文献
6.
S.A. Eremin S.V. Zaitchev A.M. Egorov A.N. Ermakov A.V. Smirnov B.N. Izotov 《Analytica chimica acta》1989
Two polarization fluoroimmunoassays for the screening of amphetamine and methamphetamine in urine were adapted for use with the Abbott TDx-Analyzer running in the automatic mode. The detection limits of amphetamine and methamphetamine in 10 μl of urine were 0.03 and 0.05 mg l?1, respectively. These assays were specific for the determination of amphetamine (cross-reactivity with methamphetamine 1%) or for the determination of methamphetamine (cross-reactivity with amphetamine 2.5%). No significant cross-reaction was observed with other drugs of abuse (ephedrine, morphine and butabarbital). 相似文献
7.
Fluorescence polarization immunoassay methods for the detection of pesticides and their metabolites or degradation products are reviewed. Advantages and limitations for application to pesticide detection in environmental and food samples are discussed. The influence of the structure of fluorescent-labeled tracers and the affinity and specificity of antibodies on analytical performance is examined. The methods are simple, readily automated, and rapid (total time for assay of a water sample is about 1 min) with sensitivity of 1 - 10 ng/ml pesticide in 0.01 - 0.1 ml sample. 相似文献
8.
An attempt was made to obtain iron-carbon nanoparticles by two-step pyrolysis of Fe(CO)5- and C3O2-containing mixtures behind incident and reflected shock waves in a shock tube. The formation of binary particles was monitored by recording the extinction of He-Ne laser radiation and laser-induced incandescence (LII). The LII method provides particle size estimates if the thermal and optical properties of the constituting material are known. Behind an incident shock wave, at temperatures of 700–1500 K, Fe(CO)5 decomposes within a short period of time (∼50 µs). The resulting iron atoms combine into particles, which serve as condensation nuclei for carbon vapor resulting from C3O2 pyrolysis at 1500–3000 K behind the reflected shock wave. The binary particles thus produced are considerably larger than pure carbon or iron particles. As the mixture temperature behind the reflected shock wave is raised, the diameter of these binary particles decreases.__________Translated from Kinetika i Kataliz, Vol. 46, No. 3, 2005, pp. 333–343.Original Russian Text Copyright © 2005 by Gurentsov, Eremin, Roth, Starke.Based on a report at the VI Russian Conference on Mechanisms of Catalytic Reactions (Moscow, October 1–5, 2002). 相似文献
9.
S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
10.
Sofronova S. N. Eremin E. V. Molokeev M. S. Mikhashenok N. V. Kartashev A. V. 《Physics of the Solid State》2021,63(4):654-659
Physics of the Solid State - The Pb3Mn7O15 crystals doped with titanium ions have been synthesized. The study of the structural properties has shown that titanium ions occupy positions in the... 相似文献