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991.
K. A. Shashkeev V. S. Nagornaya I. A. Volkov S. V. Kondrashov T. P. D’yachkova A. I. Kondakov K. M. Borisov G. Yu. Yurkov 《Russian Journal of Applied Chemistry》2017,90(7):1107-1116
Preparation of superhydrophobic conducting coatings based on silicone matrix and two types of carbon nanotubes, native and modified with alkyl groups, is described. The amount of carbon nanotubes per unit surface area was kept constant in all the samples, whereas the content of the polymer matrix was varied. The electrical conductivity, contact angle, and sliding angle were measured. The structure of the coatings was studied with an optical profilometer and a scanning electron microscope. The largest contact angle was 158.4° for the sample with 50 wt % content of native carbon nanotubes. For the samples with more than 20 wt % content of carbon nanotubes of both types, the sliding angle was less than 1°. Changes in the micro- and nanostructure of the coatings, observed with variation of the content of the polymer matrix in the samples, were studied. The relationship between the structural changes, on the one hand, and hydrophobic and water sliding properties of the conducting coatings, on the other hand, was demonstrated. 相似文献
992.
I. V. Taydakov B. E. Zaitsev S. S. Krasnosel��skiy Z. A. Starikova R. S. Borisov 《Russian Chemical Bulletin》2011,60(8):1595-1600
A reaction of Eu(NO3)3·6H2O with the novel heterocyclic ligand 1,3-bis(1,3-dimethyl-1H-pyrazol-4-yl)propane-1,3-dione and 1,10-phenanthroline in the presence of NaOH gave the complex Eu(phen)L3·5CH2Cl2. The crystal structure of the complex was determined by single-crystal X-ray diffraction. The coordination polyhedron {EuO6N2} is a tetragonal antiprism. The complex shows bright orange-red luminescence in both the solid state and solution. 相似文献
993.
New optical sensors for trace amounts of oxygen are based on platinum(II) and palladium(II) complexes of 5,10,15,20-meso-tetrakis-(2,3,4,5,6-pentafluorphenyl)-porphyrin covalently attached to the surface of amino-modified silica-gel particles. The dye-doped silica-gel particles are dispersed in silicone rubber. The Stern–Volmer plots show linear response and are virtually identical for either luminescence intensity and decay time. Other features include high photostability and rapid response times (∼150 ms in gas phase). The sensors based on the palladium(II) complex show significantly higher sensitivity (KSV about 67 kPa−1 at 25 °C) with the dynamic range from 0.02 to 100 Pa. The sensitivity of the platinum(II) complexes is significantly lower (KSV = 3.7–4.2 kPa−1, dynamic range 0.3–1000 Pa). The sensors can be suitable for application in breweries, water boilers and for marine research (monitoring of oxygen minimum zones). 相似文献
994.
P. A. Stabnikov A. I. Smolentsev N. V. Pervukhina O. S. Koshcheeva L. N. Komissarova S. V. Borisov 《Journal of Structural Chemistry》2011,52(1):118-124
The structure of aluminum(III) tris-dipivaloylmethanate (Bruker Nonius X8 Apex diffractometer with a 4K CCD detector, λMoK α, graphite monochromator, T = 150(2) K) is determined, and the synthetic procedure for its preparation is suggested. Crystal data are: C2/c space group, a = 28.1587(12) Å, b = 18.5170(7) Å, c = 21.5332(8) Å, β = 97.573(1)°, V = 11129.8(8) Å3, Z = 12, d x = 1.033 g/cm3, R = 6.93. The complex has a molecular structure; the aluminum atom is octahedrally surrounded by six oxygen atoms of three chelating ligands; Al-O distances are 1.860(2)–1.873(2)0A; O-Al-O angles fall within 88.08(9)–91.96(10)° and 177.93(9)–179.83(14)°. The known crystal packings of metal tris-dipivaloylmethanates are analyzed. Three types of the arrangement of the molecules in the crystals denoted as α, β, and γ are identified. 相似文献
995.
V. P. Petukhov A. M. Borisov V. S. Avilkina Yu. S. Virgil’ev P. N. Chernykh 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(2):322-325
Kossel line profiles were experimentally studied upon 1.5-MeV proton excitation of characteristic K
α radiation of argon atoms implanted into an UPV-1T graphite quasi-crystal. It was found that Kossel line profiles depend on
argon ion implantation conditions, i.e., the lines generated in crystals implanted at temperatures of 150 and 200°C exhibit
different widths and contrasts. In addition to the main Kossel cone line, a second cone line was detected caused by an additional
texture component in the UPV-1T pyrolytic graphite quasi-crystal. 相似文献
996.
A. M. Galper S. V. Borisov V. G. Zverev C. I. Suchkov N. P. Topchiev M. O. Farber M. I. Fradkin Yu. T. Yurkin 《Bulletin of the Lebedev Physics Institute》2011,38(7):191-197
When designing devices of modern gamma astronomy, one of the most important problems is achieving the maximum possible angular
resolution. This study is devoted to the method for reconstructing the arrival direction of primary gamma-rays with energies
E
γ > 10 GeV in the GAMMA-400 satellite experiment. By the example of the GAMMA-400 gamma telescope, the possibility of improving
the angular resolution of gamma telescopes incorporating a “converter + calorimeter” system is shown. The dependence of the
angular resolution on the step of silicon strips used to determine the coordinates of incident particles in the converter
and calorimeter and the distance between the converter and calorimeter is analyzed. 相似文献
997.
The life and career of the great French mathematician and politician Paul Painlevé is described. His contribution to the analytical theory of nonlinear differential equations was significant. The paper outlines the achievements of Paul Painlevé and his students in the investigation of an interesting class of nonlinear second-order equations and new equations defining a completely new class of special functions, now called the Painlevé transcendents. The contribution of Paul Painlevé to the study of algebraic nonintegrability of the N-body problem, his remarkable observations in mechanics, in particular, paradoxes arising in the dynamics of systems with friction, his attempt to create the axiomatics of mechanics and his contribution to gravitation theory are discussed. 相似文献
998.
Leonid G. Voskressensky Alexander A. Titov Tatiana N. Borisova Anna V. Listratova Roman S. Borisov Larisa N. Kulikova Alexey V. Varlamov 《Tetrahedron》2010,66(27-28):5140-5148
A novel and efficient one-pot synthesis of pyrrolo[1,2-d][1,4]diazocines based on tandem transformation of tetrahydropyrazine ring was elaborated. 相似文献
999.
1000.