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1.
The angular variations of the five-fold differential cross section obtained by using different wave functions of helium are
compared with experimental data. It is found that in the coplanar geometry two kinematical arrangements, (i) equal energy
sharing between the two ejected electrons with one of them ejected along the momentum transfer direction and the other along
varying direction and (ii) the Bethe ridge condition with fixed sum of ejected electron energies and varying angle between
them, are very sensitive to e-e correlations contained in the target wave function. This comparison has been used to show
that open-shell class of wave functions better incorporate e-e correlations than the closed-shell class. 相似文献
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Fiksel G Hudson B Den Hartog DJ Magee RM O'Connell R Prager SC Beklemishev AD Davydenko VI Ivanov AA Tsidulko YA 《Physical review letters》2005,95(12):125001
Fast ions are observed to be very well confined in the Madison Symmetric Torus reversed field pinch despite the presence of stochastic magnetic field. The fast-ion energy loss is consistent with the classical slowing down rate, and their confinement time is longer than expected by stochastic estimates. Fast-ion confinement is measured from the decay of d-d neutrons following a short pulse of a 20 keV atomic deuterium beam. Ion confinement agrees with computation of particle trajectories in the stochastic magnetic field, and is understood through consideration of ion guiding center islands. 相似文献
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D. P. Beklemishev M. A. Gaidamako L. I. Gurevich V. I. Chernetsov 《Mechanics of Composite Materials》1965,1(4):52-55
Results are given of investigations of certain strength characteristics of a number of thermosetting plastics in relation to the scale of specimens reduced to 1/5 the standard size, i. e., the effect of the scale factor on the mechanical characteristics of plastics in compression and shear. In addition, results of a study of the dependence of the mechanical characteristics of plastics on the degree of heating in the temperature range from 20 to 200°C, i. e., the effect of the temperature factor on these characteristics, are also given.Mekhanika Polimerov, Vol. 1, No. 4, pp. 92–99, 1965 相似文献
6.
M. K. Beklemishev E. N. Kiryushchenkov E. K. Skosyrskaya A. M. Petrenko 《Journal of Analytical Chemistry》2006,61(11):1067-1073
The kinetics of 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation by sodium periodate in an aqueous solution was studied. For the auto-acceleration regime, the experimental data correspond to the kinetic equation w t = k[P] t 1/2 [IO 4 ? ] t 1/2 [TMB]0, where w t is the accumulation rate of the meriquinoid product (P) of TMB oxidation and [P]t and [IO 4 ? ]t are the concentrations of product P and periodate, respectively, at time t. A radical chain mechanism was proposed; the mechanism explains the experimental kinetic equation and complies with the observed inhibiting effect of metal ions (Zn, Cd) in this reaction. 相似文献
7.
The aim of this brief report is to study the behaviour of sheath structure in a multi-component plasma with dust-neutral collisions.
The plasma consists of electrons, ions, micron size negatively charged dust particles and neutrals. The sheath-edge potential
and sheath width are calculated for collisionally dominated sheath. Comparison of collisionless and collisionally dominated
sheath are made. 相似文献
8.
Determination of copper by its catalytic effect on the oxidation of hydroquinone by hydrogen peroxide on supports 总被引:1,自引:0,他引:1
Yu. Yu. Petrova M. K. Beklemishev N. A. Bazhanova A. A. Druzhinin I. F. Dolmanova 《Journal of Analytical Chemistry》2000,55(3):284-290
The reaction of oxidation of hydroquinone by hydrogen peroxide catalyzed by copper(II) in the presence of 2,2’-dipyridyl is
activated by hexamethylenediamino groups that are bonded to the surface of filter paper; additional activating effect is produced
by 2,2′-dipyridyl. The introduction of malonic acid dinitrile into the indicator reaction improves the sensitivity of the
determination of copper and the contrast of the reaction in solution because of the formation of a blue product. Differently
colored compounds are formed on a paper support at different concentrations of copper, which makes it possible to visually
distinguish the quantities of copper that differ by an order of magnitude in the range 1 × 10-5-0.5 μg. Quantitative detection is possible in the range 5 × 10-6-0.1 μg (cmin = 3 × 10-6 μg). The concentration of copper (0.2-1.5 μg/mL) is determined in blood serum; the consumption of the sample per one determination
is 3 μL 相似文献
9.
M. K. Beklemishev E. N. Kiryushchenkov T. A. Stoyan I. F. Dolmanova 《Journal of Analytical Chemistry》2005,60(6):589-595
The inhibitory effect of Cd(II), Ni(II), and Zn(II) on the oxidation of 3,3′,5,5′ -tetramethylbenzidine with periodate was detected. The optimum reaction conditions were found, and the procedures were developed for determining 1 × 10−2 to 10 μg/mL Cd(II), Ni(II), and Zn(II) in solution. The indicator reaction was performed on a number of supports. The maximum inhibitory effect was observed on silica gel-based plates for TLC. Procedures for determining 6 × 10−3 to 0.4 μg of these metals were developed. Silica gel plates with the immobilized reagent for cadmium (bromobenzothiazo) were used to preconcentrate cadmium. A selective test procedure was developed for determining 1 × 10−4 −3 × 10−3 μg/mL cadmium with the visual detection of the process rate. Upon the introduction of dimethylglyoxime into the indicator reaction, the inhibitory effect of nickel changed to its promoting effect and the detection limit for nickel was lowered. A procedure was developed for determining 3 × 10−4 −3 × 10−3 μg/mL nickel in solution and 7 × 10−3−4 × 10−1 μg nickel on the surface of Sorbfil plates. An assumption was made about the reasons for the inhibitory effect of metal ions on the oxidation of aryl diamines with periodate.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 6, 2005, pp. 662–669.Original Russian Text Copyright © 2005 by Beklemishev, Kiryushchenkov, Stoyan, Dolmanova. 相似文献
10.
Sorption of copper on filter-paper with chemically attached hexamethylenediamino-groups (HMDA-filter) allows to obtain the
sorbent (Cu/HMDA-filter) stable in respect to desorption of copper. A nitrogen-containing herbicide imazapyr (imaz) is retained on Cu/HMDA-filters at pH 5.5–7.0 forming a relatively stable complex. Imazapyr is determined directly on the
sorbent by its activating effect in the oxidation of hydroquinone with H2O2 catalyzed by Cu(II) with the formation of a product absorbing at 490 nm. The copper ions serve both to preconcentrate imazapyr
and to catalyze the indicator reaction. The use of 1-μL sample aliquots pipetted onto the Cu/HMDA-filters allows to determine
1 × 10−3–0.03 μmol of imazapyr, whereas preconcentration of the analyte by pumping of its solution through the same sorbent expands
the linear range to 1 × 10−4–1 × 10−1 μmol of imazapyr. When the indicator reaction is carried out in solution, the range of activating action of imazapyr is narrower
(0.06–0.1 μmol a for a solution volume of 10 mL). The determination is selective: 5–100-fold amounts of amines, aminoacids,
carboxylic acid derivatives and other model compounds do not interfere. Soil extracts and carrot juice samples spiked with
imazapyr have been analyzed.
Received January 10, 2000. Revision July 28, 2000. 相似文献