排序方式: 共有12条查询结果,搜索用时 15 毫秒
1.
A. A. Bumber Yu. N. Nechitailov I. A. Profatilova E. G. Ignatenko 《Journal of Analytical Chemistry》2000,55(7):666-668
Anin situ obtained graphite-fiber-based thin-film mercury microelectrode was used for determining lead(II) in natural water by stripping
voltammetry without removing oxygen and using no supporting electrolyte. Under the optimum voltammetric conditions (E
el = -1.2 V,t
el = 5 min,c
Hg(II) = 1 x 10-7 M, ΔE = 40 mV, v= 105 mV/s), the calibration graph was linear in the range of actual lead(II) concentrations in natural waters.
At a lead(II) concentration of 0.002 mg/L, the RSD was 11%. 相似文献
2.
I. A. Profatilova A. A. Bumber I. E. Tolpygin V. P. Rybalkin T. N. Gribanova I. E. Mikhailov V. A. Bren' 《Russian Journal of General Chemistry》2005,75(11):1774-1781
The redox activity of potent chemosensors based on anthryl-containing diamines, thioureas, and ureas in the absence and in the presence of complexing metal cations in solution was studied by cyclic and differential pulse voltammetry. The free energy of intramolecular electron transfer was calculated. The experimental conclusions were confirmed by ab initio RHF/6-31G** calculations. A correlation was found between the electrochemical and photophysical data for the compounds studied. 相似文献
3.
I. A. Profatilova A. A. Bumber I. E. Mikhailov G. A. Dushenko M. P. Bubnov V. K. Cherkasov 《Russian Journal of Electrochemistry》2008,44(7):812-817
Redox reactions of a series of substituted cycloheptatrienes are studied on a platinum electrode in acetonitrile using the cyclic voltammetry method. It was found that heptaphenyl-substituted cycloheptatrienes are irreversibly oxidized in two stages in the range of high anodic potentials to form unstable radical cations and dications. As opposed to the unsubstituted and monosubstituted cycloheptatrienes, they are not reduced at the potentials higher than ?2 V (SCE). A new stable radical anion was found in the reduction of N-cycloheptatrienylphthalimide. Its spin density distribution is studied by ESR spectroscopy. 相似文献
4.
Specific cell arrangement corresponding to four probe pouch cell with two reversible current and two indifferent potential
electrodes is applied to study the existence of frequency dependence on conductivity of a medium between two potential electrodes,
i.e., separator impregnated with electrolyte. It is established that frequency dependence of conductivity for carbonate-based
electrolyte solution does exist. Series resistance is found to be in a good agreement by specific value with that reported
earlier. Low frequency limit of impedance spectra is a few decimal orders higher than that of series resistance. Both low-
and high-frequency resistances increase with the interelectrode distance in agreement with Ohm law. 相似文献
5.
A four-probe pouch-type cell was used to study the influence of carbonate-based electrolyte composition on the total conductivity
of polyolefin separator impregnated with electrolyte through the electrochemical impedance spectroscopy. A frequency dispersion
of separator with electrolyte is found to be dependent on the volume ratio of ethylene carbonate and ethyl methyl carbonate
in an electrolyte solution. The origin of high- and low-frequency relaxation processes obtained from the impedance spectra
is discussed. A correlation between the direct current resistance of separator with electrolyte and dissociation degree of
electrolyte salt is found. 相似文献
6.
A. A. Bumber G. A. Dushenko I. A. Profatilova A. A. Arutyunyants I. E. Mikhailov 《Russian Journal of Electrochemistry》2000,36(5):553-556
Redox processes of fluctuating pentaphenyl(methoxycarbonyl)cyclopentadiene derivatives on platinum electrode in acetonitrile
are studied by cyclic voltammetry. The reduction of derivatives of pentaphenylcyclopentadiene C5Ph5M yields a radical anion which decomposes to anion M- and stable radical C5Ph
5
•
; the latter reduces to C5Ph5. In the first stage of oxidation of these compounds, a stable radical cation forms, with substituent M intact. Reduction
of derivatives of pentamethoxycarbonylcyclopentadiene [C5(CO2Me)5]M yields a dianion. Such electrochemical behavior of fluctuating cyclopentadiene compounds reveals additional information
on the mechanism of displacement of the element-centered substituents M in them 相似文献
7.
Nam-Soon Choi Irina A. Profatilova Sung-Soo Kim Eui-Hwan Song 《Thermochimica Acta》2008,480(1-2):10-14
The thermal reactions of a lithiated graphite anode with and without 1.3 M lithium hexafluorophosphate (LiPF6) in a solvent mixture of ethylene carbonate (EC) and ethylmethyl carbonate (EMC) were investigated by means of differential scanning calorimetry (DSC). The products of the thermal decomposition occurring on the lithiated graphite anode were characterized by Fourier transform infrared (FT-IR) analysis. The lithiated graphite anode showed two broad exothermic peaks at 270 and 325 °C, respectively, in the absence of electrolyte. It was demonstrated that the first peak could be assigned to the thermal reactions of PF5 with various linear alkyl carbonates in the solid electrolyte interphase (SEI) and that the second peak was closely related to the thermal decomposition of the polyvinylidene fluoride (PVdF) binder. In the presence of electrolyte, the lithiated graphite anode showed the onset of an additional exothermic peak at 90 °C associated with the thermal decomposition reactions of the SEI layer with the organic solvents. 相似文献
8.
V. T. Abaev I. A. Profatilova A. V. Butin V. V. Mel’chin A. A. Bumber 《Russian Journal of General Chemistry》2006,76(12):1948-1952
With the purpose of establishing of mechanism of the furan ring oxidative cleavage in 9-furylnaphtho[2,3-b]furans obtained recently, their cyclic voltammometric study was carried out. Ability of these compounds to undergo three-step oxidation is revealed. Radical cations of the compounds under study formed in the first step of electrooxidation are partially stable. Comparison of the electrochemical characteristics of 9-furylnaphtho[2,3-b]furan with those of the specially prepared unsaturated 1,4-diketones showed that one of the pathways of further transformations of the compounds under investigation is the formation of the corresponding unsaturated 1,4-diketones. The results obtained tell in favor of participation of the 9-furylnaphtho-[2,3-b]furan radical cations in the process of chemical oxidation. 相似文献
9.
Bumber A. A. Kornienko I. V. Profatilova I. A. Vnukov V. V. Kornienko I. E. Garnovskii A. D. 《Russian Journal of General Chemistry》2001,71(8):1311-1313
Classical polarography and cyclic voltammetry were used to study the effect of a series of water-soluble amino acids and serum albumins on oxygen reduction in aqueous solutions. Positive or negative shifts of the reduction potential of oxygen were revealed, depending the nature of the compounds. The feasibility of polarographic methods for studying antioxidant properties of compounds was demonstrated. 相似文献
10.