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21.
V. A. Drozdov P. G. Tsyrulnikov V. V. Popovskii N. N. Bulgakov E. M. Moroz T. G. Galeev 《Reaction Kinetics and Catalysis Letters》1985,27(2):425-427
Atomic catalytic activity of palladium has been revealed to be higher than that of platinum in deep oxidation of methane and lower in the case of butane. According to the experimental data and the quantum-chemical calculation, the observed effects are ascribed to the different bond strength of the surface oxygen due to different reaction conditions.
, Pd Pt, . Pd Pt - , .相似文献
22.
The mineral and microelement composition of natural manganese minerals from iron-manganese concretions of the Bol’shoe Miassovo lake (South Ural) is investigated. The structural transformations of the samples under the effect of different temperatures are studied. Apart from layered 9.6 Å and 7.2 Å structures of manganese minerals the lake samples often contain various manganese-containing carbonates. For carbonate minerals by IR spectroscopy the dependence of the wavenumbers of ν2 and ν4 vibrations of the CO3 group on the mineral composition is analyzed. The composition of macro- and microelements of iron-manganese concretions of Bol’shoe Miassovo lake varies in wide ranges not only in different samples, but also in different parts of the same sample. An analysis of the microstructure of lake manganese concretions revealed their biomorphic nature that is exhibited in globe-shaped to filament organic bacterial forms. 相似文献
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Chernov N. M. Moroz T. V. Shutov R. V. Kuz’mich N. N. Shchegolev A. E. Sopova M. V. Yakovlev I. P. 《Russian Journal of General Chemistry》2019,89(12):2463-2470
Russian Journal of General Chemistry - The effect of electronic properties of substituents in the reactants on the [4+2]-cycloaddition of 3-vinyl-chromen-4-ones (dienes) and N-vinylpyrrolidines... 相似文献
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N. A. Pal’chik T. N. Grigor’eva T. N. Moroz 《Russian Journal of Inorganic Chemistry》2013,58(2):138-143
The mineral and microelement composition and structures have been studied and a comparative analysis has been carried out for manganese minerals with the general formula [Mn(O,OH)2]+[R0.5–1(OH)21.5] · nH2O (R = Mn, Na, K, Ni, Co, Ca, and others) that built iron-manganese concretions raised from different areas of the Sea of Okhotsk and the Bering Sea, and their synthetic analogues. The structures of synthetic manganese species were found to better withstand temperature impacts than those of the native minerals studied under the same conditions. 相似文献
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In an earlier paper (see Proc. London Math. Soc. (3) 84 (2002)257288) we showed that an irreducible integral binarycubic form f(x, y) attains infinitely many prime values, providingthat it has no fixed prime divisor. We now extend this resultby showing that f(m, n) still attains infinitely many primevalues if m and n are restricted by arbitrary congruence conditions,providing that there is still no fixed prime divisor. Two immediate consequences for the solvability of diagonal cubicDiophantine equations are given. 2000 Mathematics Subject Classification11N32 (primary), 11N36, 11R44 (secondary). 相似文献
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Rabbit liver was loaded with ferrimagnetic particles of gamma -Fe2 O3 (designed for magnetic hyperthermia treatment of liver tumors) by injecting various doses of a suspension of the particles into the hepatic artery in vivo. Proton transverse relaxation rate (R(2)) images of the livers in vivo, excised, and dissected were generated from a series of single spin-echo images. Mean R(2) values for samples of ferrimagnetic-particle-loaded liver dissected into approximate 1 cm cubes were found to linearly correlate with tissue iron concentration over the range from approximately 0.1 to at least 2.7 mg Fe/g dry tissue when measured at room temperature. Changing the temperature of ferrimagnetic-particle-loaded samples of liver from 1 degrees C to 37 degrees C had no observable effect on tissue R(2) values. However, a small but significant decrease in R(2) was found for control samples containing no ferrimagnetic material on raising the temperature from 1 degrees C to 37 degrees C. Both chemically measured iron concentrations and mean R(2) values for rabbit livers with implanted tumors tended to be higher than those measured for tumor-free liver. This study indicates that tissue R(2) measurement and imaging by nuclear magnetic resonance may have a useful role in magnetic hyperthermia therapy protocols for the treatment of liver cancer. 相似文献