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21.
Presnova G Grigorenko V Egorov A Ruzgas T Lindgren A Gorton L Börchers T 《Faraday discussions》2000,(116):281-9; discussion 335-51
Clean polycrystalline gold electrodes were modified with native glycosylated horseradish peroxidases (HRP) or two different recombinant (carbohydrate free) HRPs; recombinant wild-type HRP (rec-HRP) and recombinant HRP containing a six histidine-tag at the C-terminus of the polypeptide chain (rec-HRP-His), respectively. Only the electrodes modified with the recombinant HRPs exhibited high current responses to H2O2 due to relatively rapid direct electron transfer (ET) between recombinant HRP and gold. The absence of a carbohydrate shell on rec-HRP and the additionally existing histidine-tag on rec-HRP-His improved the electrode sensitivity to H2O2 by more than 100 times if compared with the response observed at gold modified with native HRP. Rotating disk electrode experiments indicated that the heterogeneous electron transfer rates are equal to 4.7 and 7.5 s-1 for direct electron transfer between the gold electrode and rec-HRP or rec-HRP-His, respectively. 相似文献
22.
Egorov V. V. Rakhman'ko E. M. Gulevich A. L. Lomako S. V. Rat'ko A. A. 《Russian Journal of Coordination Chemistry》2002,28(10):709-725
The possibility of producing liquid anion-selective electrodes with improved selectivity based on the capability of the metal atom to coordinate the analyzed anions is illustrated using numerous examples. The subjects under consideration were electrodes based on high-stable lipophilic metal complexes with polydentate organic ligands, electrodes based on lipophilic organometallic compounds capable of coordinating anionic ligands, and electrodes based on higher quarternary ammonium salts that respond to lipophilic anionic metal complexes, in particular, the electrodes with the ligand function. The theoretical principles underlying the above electrode operation are discussed. Methods for optimizing the composition of the membrane and of the studied solution are suggested with the aim to improve the selectivity of the electrode. 相似文献
23.
L.A. Leites A.V. Zabula S.S. Bukalov A.A. Korlyukov P.S. Koroteev O.S. Maslennikova M.P. Egorov O.M. Nefedov 《Journal of Molecular Structure》2005,750(1-3):116-122
Vibrational (Raman and IR) spectra of the 1:1 complexes of dihalogermylene and dihalostannylene with 1,4-dioxane and PPh3 have been reported, the structures of the complexes Cl2Ge·C4H8O2 and Cl2Ge·PPh3 updated using high-resolution X-ray method. Quantum-chemistry calculations of the geometry and normal mode frequencies and eigenvectors were carried out for some of the complexes. The results show that in the structure of the polymeric solid complexes of X2M with 1,4-dioxane, intermolecular coordination XM plays a prominent role, whereas the corresponding complexes with PPh3 are monomeric. In the vibrational spectra of all the complexes, an inversion of symmetric and antisymmetric stretching νXM (X=Cl, Br; M=Ge, Sn) frequencies, found for ‘free’ X2MII particles, still persists, suggesting that the X2M moieties preserve their specifity as carbene analogues also in the complexes. 相似文献
24.
S. N. Tandura S. P. Kolesnikov M. P. Egorov K. S. Nosov O. M. Nefedov 《Russian Chemical Bulletin》1997,46(3):602-604
Assignment of all of the signals in the1H and13C NMR spectra of 1,1-dichloro-2,3,4,5-tetraphenyl-l-germacyclopenta-2,4-diene has been carried out using two-dimensional NMR
spectroscopy.
Translated fromIzvestiya Akademii Nauk Seriya Khimicheskaya, No. 3, pp. 623–625, March, 1997. 相似文献
25.
L. A. Leites A. V. Zabula S. S. Bukalov P. S. Koroteev O. S. Maslennikova M. P. Egorov O. M. Nefedov 《Russian Chemical Bulletin》2005,54(5):1117-1120
The vibrational spectra of tetravalent metal halides (M = Si, Ge, Sn) and the corresponding dihalocarbene analogs MIIHal2, obtained by the authors, and the relevant published data are compared. The spectra of the MIIHal2 species exhibit inversion of the M-Hal stretching frequencies (νs(MIIHal) > ν as(MIIHal)). This can be used for analytical purposes and allows one to distinguish between the spectra of the MIV and MII halides. The IR and Raman spectra of the complexes of dihalogermylenes and -stannylenes with triphenylphosphine and 1,4-dioxane
also exhibit inversion of the ν(MHal) stretching frequencies. This confirms the conclusion drawn earlier based on the analysis
of the geometric parameters and reactivities of the complexes in question that the divalent state of the M atom in these species
is retained.
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1089–1092, May, 2005. 相似文献
26.
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
27.
28.
Yu. P. Egorov 《Theoretical and Experimental Chemistry》1988,24(6):655-664
Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 6, pp. 685–695, November–December, 1988. 相似文献
29.
30.
Physical principles are given for the method, which employs changes in the absorption and luminescence spectra of trace components in research on the structural and phase transitions in the polymer matrix. The scope of the method is demonstrated for polyethylene as matrix (a typical two-phase system), with anthracene as the probe. The spectrum shifts about 750 cm–1 to longer wavelengths in the crystalline phase relative to the amorphous phase. Such shifts are very sensitive to temperature and to mechanical damage to the polyethylene, so it is possible to follow temperature trends in the densities of the amorphous and crystalline regions; the bulk expansion coefficients can be measured, as can the vitrification temperature. It can be shown that the melt (50 above the melting point) contains crystalline regions of fluctuation type.Tests on cold drawing of polyethylene reveal melting (recrystallization) of the supermolecular structure in the neck region, in accordance with Kargin's views. The method is thus applicable to second-order phase transitions.Anthracene in the crystalline regions shows a considerable enhancement of the luminescence intensity, evidently from migration of energy from molecules in the amorphous material. 相似文献