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961.
The electrocatalytic oxidation of 2-propanol was investigated using on line differential electrochemical mass spectrometry (DEMS) on electrodeposited Pt and an arrange of bimetallics: Pt0.84Rh0.16, Pt0.70Rh0.30, Pt0.55Rh0.45. It has been observed that the Pt0.84Rh0.16 bimetallic electrode presented the best catalytic activity for 2-propanol electrochemical oxidation. Since 2-propanol is a secondary alcohol, only acetone and CO2 are produced. The total yield of CO2 and acetone has been determined from the DEMS measurements. It is found that acetone is the major product, as reported before for other electrodes. The acetone and CO2 yield depends on the electrode composition. High amount of rhodium in the electrode composition strongly diminish the reaction rate as indicated by the decrease of both the acetone and CO2 yield. However, acetone inhibition is much more intense. The only bimetallic electrode that presents considerable mass spectroscopy signals intensity for CO2 and acetone is the Pt0.84Rh0.16 electrode. This electrode shows a slight increase in CO2 selectivity, compared to the other electrodes studied in this work. Only very low coverages of stable adsorbates were present during the reaction. Two and one carbon adsorbate were observed for all the electrodes. Three carbon adsorbates were detected only for the Pt0.84Rh0.16 electrode. Therefore, acetone production does not require a stable adsorbate. 相似文献
962.
Yu. I. Ryabukhin A. Yu. Eliseeva K. F. Suzdalev 《Chemistry of Heterocyclic Compounds》1992,28(2):236-237
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 280–281, February, 1992. 相似文献
963.
S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of the Ukraine. Translated from Prikladnaya Mekhanika, Vol. 31, No. 9, pp. 15–23, September, 1995. 相似文献
964.
965.
L. D. Smirnov S. V. Nikitin A. I. Chernyshev A. A. Sorokin V. P. Lezina V. G. Zabrodnyaya M. M. Kaganskii 《Chemistry of Heterocyclic Compounds》1992,28(12):1425-1431
It has been shown that the alkylation of 2-methyl-9-hydroxy-4H-pyrido[1,2-a]pyrimidin-4-one takes place at the oxygen atom, but electrophilic substitution takes place mainly at position 8 of the molecule (the ortho position relative to the hydroxy group).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1660–1666, December, 1992. 相似文献
966.
E.P. Yelsukov Yu.N. Vorobyov T.I. Arbusova I.B. Smolyak 《Journal of magnetism and magnetic materials》1994,130(1-3):44-50
We have measured the concentration dependence of the average magnetic moment per Fe atom
Fe(x) in microcrystalline and amorphous Fe-P alloys obtained over a wide concentration range using electrochemical deposition. The model of local magnetic moments has been used to described
Fe(x). On the basis of this model the effects of phosphorus on the value
Fe are explained in terms of the parameters of the local environment of the Fe atom. 相似文献
967.
968.
969.
Room temperature transmission Mössbauer spectra of Fe62Ni16B14Si8 ribbons, annealed in vacuum for time periods ranging from 5 to 60 minutes at the crystallization temperatureT
x=720 K, have been used to investigate the crystallization mechanism by isothermal annealing. Reorientation of the magnetic anisotropy almost normal to the ribbon plane was observed and correlated to the annealing time dependence of the mean hyperfine field (HF) of the amorphous component. Crystallization started at the surface before the bulk and was found to occur in two steps: a metastable equilibrium of the amorphous phase with (FeNi), (FeNi)Si and t-(FeNi)3B, followed by the decomposition of t-(FeNi)3B into t-(FeNi)2B and (FeNi). The increase of the mean magnetic moment at the Fe sites as compared to related iron-based alloys was attributed to compositional small Ni additions. 相似文献
970.
I. D. Protasov 《Theoretical and Mathematical Physics》1995,105(3):1581-1592
State equations for simple lattice systems are constructed by extending the Gibbs method to a non-equilibrium system.In memory of D. N. Zubarev, teacher and scientist, whose advice and attention are gratefully remembered.The idea of constructing such a model (on the basis of the vacancy model of condensed matter proposed by the author) belongs to D. N. Zubarev.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 105, No. 3, pp. 478–490, December, 1995. 相似文献