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排序方式: 共有119条查询结果,搜索用时 54 毫秒
61.
62.
S. V. Budukva O. V. Klimov G. S. Litvak Yu. A. Chesalov I. P. Prosvirin T. V. Larina A. S. Noskov 《Russian Journal of Applied Chemistry》2011,84(1):95-102
Oxidative regeneration of a deactivated IK-GO-1 catalyst was studied in removal of carbonaceous deposits and sulfur from the catalyst composition. Elemental analysis data, texture characteristics, and catalytic activities of fresh and regenerated samples were compared. Raman spectroscopy, X-ray phase analysis, electronic diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy were used to examine the structure of cobalt and molybdenum compounds entering into the composition of the catalysts. 相似文献
63.
64.
V. I. Prosvirin 《Mechanics of Composite Materials》1971,7(3):506-508
It is shown that acrylics have a notch sensitivity determined by the nature of the state of stress produced by the loading.Lenin Riga Komsomol Institute of Civil Aviation Engineers. Translated from Mekhanika Polimerov, No. 3, pp. 562–564, May–June, 1971. 相似文献
65.
It is shown that increasing the length of a vee notch in polymethyl methacrylate sheet specimens does not significantly intensify the effectiveness of the notch as stress raiser. Over a broad interval of variation of its length the notch has a constant quantitative effect on the mechanical properties.Lenin Riga Komsomol Institute of Civil Aviation Engineers. Translated from Mekhanika Polimerov, No. 4, pp. 745–747, July–August, 1971. 相似文献
66.
It is shown that after a glass-reinforced plastic (GRP) has been molded the properties of the surface layer differ sharply from those of the interior layers of material. The surface layer is stronger and less moisture-absorbent. The properties of the surface layer and its thickness are determined by the parameters of the molding process. The surface layer of the GRP AG-4V is thickest, hardest and least moisture-absorbent after molding at 130° C and 200 kg/cm2. In this case the microstructure is characterized by a highly uniform fiber distribution without signs of splitting or other damage.Mekhanika Polimerov, Vol. 1, No. 5, pp. 118–122, 1965 相似文献
67.
O. V. Netskina O. V. Komova I. P. Prosvirin A. A. Pochtar’ A. M. Ozerova V. I. Simagina 《Russian Journal of Applied Chemistry》2017,90(10):1666-1673
Calcined boron–cobalt catalysts prepared by reduction of cobalt chloride in an aqueous sodium borohydride solution can be successfully used as components of pelletized solid-state hydrogen-generating composites based on sodium borohydride. Morphological changes and phase and chemical transformations occurring in the catalysts with an increase in the calcination temperature were studied. The catalyst performance in hydrolysis of sodium borohydride was determined. The hydrogen generation rate depends on the specific surface area of the calcined sample. 相似文献
68.
A. V. Bukhtiyarov A. Yu. Stakheev A. I. Mytareva I. P. Prosvirin V. I. Bukhtiyarov 《Russian Chemical Bulletin》2015,64(12):2780-2785
The interaction of NO with the surface of model Ag/Al2O3/FeCrAl catalysts containing Ag nanoparticles of different size (1 and 3 nm) was studied. The use of the Auger parameter αAg (E b(Ag3d5/2) + E kin(Ag MVV)) made it possible to reliably identify the change in the chemical state of silver cluster upon their interaction with О2 and NO. The oxygen treatment leads to the oxidation of small Ag nanoparticles (1 nm) and formation of AgO x clusters resulted in the intensive formation of nitrite—nitrate structures on the step of the interaction with NO. These structures are localized on both the silver clusters and Al2O3 surface. An increase in the size of Ag0 nanoparticles to 3 nm results in an increase in the stability of these structures and impedes the Ag0 → AgO x transition, due to which the formation of surface groups NO2 –/NO3 – is suppressed. The data obtained make it possible to explain the dependence of the activity of the Ag/Al2O3 catalysts in the selective reduction of NO on the Ag nanoparticle size. 相似文献
69.
A. K. Khudorozhkov A. V. Bukhtiyarov E. Yu. Gerasimov I. P. Prosvirin V. I. Bukhtiyarov 《Russian Chemical Bulletin》2015,64(12):2802-2805
Alumina-supported bimetallic Pt—Pd catalysts proved to be more active in the complete oxidation of methane than monometallic systems (Pt/Al2O3, Pd/Al2O3). The maximum activity of the bimetallic catalysts was achieved at ~40 at.% Pt in Pd on the catalyst surface. After the oxidation reaction, redistribution of platinum and palladium was observed in the active component of the catalysts with the degree of redistribution depending on the initial Pt: Pd ratio. 相似文献
70.
Reactions between [M'(III)(CN)(6)](3-) anions (M' = Co, Cr, or Fe) and mononuclear complexes of M(II) ions (M = Cr, Mn, Co, Ni, or Zn) produce a family of pentanuclear clusters {[M(tmphen)(2)](3)[M'(CN)(6)](2)]}. The core of the clusters is formed by five metal ions that are bridged through six CN- linkers into a trigonal bipyramid, with M and M' ions occupying equatorial and axial positions of the bipyramid, respectively. Three of the CN- ligands from each M' center remain terminal and point toward the outside of the cluster, along the trigonal axes. Studies of magnetic coupling in the {[M(tmphen)(2)](3)[M'(CN)(6)](2)]} family of clusters revealed a similarity between the observed magnetic exchange constants and the values estimated for the molecule-based magnets of the Prussian blue family. The type of the magnetic exchange varies across the series, changing from antiferromagnetic for M = Cr and Mn to ferromagnetic for M = Co and Ni. Complexes {[M(tmphen)(2)](3)[M'(CN)(6)](2)]}, which contain diamagnetic Co(III) ions in the axial positions, serve as convenient model compounds for an accurate assessment of the magnetic parameters for the equatorial M ions in the absence of magnetic interactions. The {[Co(tmphen)(2)](3)[Cr(CN)(6)](2)]} cluster exhibits cyanide linkage isomerism, the relative amount of which depends on the synthetic conditions. 相似文献