共查询到10条相似文献,搜索用时 218 毫秒
1.
《Reaction Kinetics and Catalysis Letters》1974,1(2):215-221
, - CuO–MgO. . ( - , , -) . , - .
The catalytic oxidation of propene over CuO–MgO has been compared with TPD and IR spectroscopic data. The products of extensive oxidation are shown to be formed from a strongly adsorbed propene species. Weakly adsorbed propene /-allyl or -complexes/ is an intermediate in the conversion of propene to to acrolein. The role of -complexes is not yet clear.相似文献
2.
The concentration dependences of the quantum yields of Norrish type II decomposition from the singlet and triplet states and of the triplet yiel were determined in pentanone-2 photolysis in iso-octane. The results were interpreted by postulating dissociative intersystem crossing of a singlet exciplex as an additional route for the population of the molecular triplet state.
II -2 . , .相似文献
3.
Adonitol is oxidized to ribose by Mn(III) pyrophosphate under the conditions [adonitol] [Mn(III)]. The oxidation rate is first order with respect to both oxidatn and substrate and decreases inversly with [pyrophosphate]free. Thermodynamic parameters are reported and a suitable mechanism involving free radicals is proposed.
(III) [] [Mn(III)]. , - []. - .相似文献
4.
V. D. Krsmanović V. Vučelic D. Vučelic D. Vitorović 《Journal of Thermal Analysis and Calorimetry》1987,32(3):835-843
The precipitated acids, obtained by partial stepwise oxidation of Aleksinac (Yugoslavia) shale kerogen, were studied by thermal analysis. Significant differences were observed in the weight loss and the shape of TG curves of precipitated acids from various degradation steps, indicating their structural differences and heterogeneity of the kerogen. The thermal curves of precipitated acids were found to consist of two distinct parts. From IR data it was found that the low-temperature part corresponded to thermal changes of aromatic, and the high-temperature part of aliphatic type structures. These results were in good agreement with chemical analysis (elemental analysis, atomic H/C ratio, total acidity) of the same acids.
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal). 1986. 相似文献
Zusammenfassung Durch partielle schrittweise Oxydierung von Schieferkerogen (Aleksinac. Jugoslavien) erhaltene präzipitierte Säuren werden thermoanalytisch untersucht. Signifikante Unterschiede wurden im Gewichtsverlust und der TG-Kurvengestalt von nach den einzelnen Abbauschritten erhaltenen präzipitierten Säuren beobachtet, was auf deren strukturelle Verschiedenheit und auf die Heterogenität des Kerogens hinweist. Die thermische Kurven der präzipitierten Säuren weisen zwei sich unterscheidende Abschnitte auf. Aus IR-Daten ergab sich, daß im Tieftemperaturabschnitt thermische Veränderungen von aromatischen, im Hochtemperaturabschnitt dagegen von aliphatischen Strukturen verlaufen. Diese Ergebnisse stimmen mit chemischen Analysendaten (Elementaranalyse, H/C-Atomverhältnis, Gesamtsäure) gut überein.
, ( ). , , , . , . , , — . ( , -, ) .
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal). 1986. 相似文献
5.
Using the Fokker-Planck version of an approximate Boltzmann equation for the ion (translational) energy distribution function fI we have calculated the deviation, k, of the non-equilibrium ion-(polar)molecule reaction rate coefficient k (based) on fI from its equilibrium value k(0). The D (dipole moment)-dependence of the reaction cross section applied leads to a corresponding dependence of k on D.
- , k - ( fI) k(0). k D.相似文献
6.
Carbon dioxide exerts a strong inhibitory effect on oxygen adsorption and complete oxidation of ethylene on silver but has little effect on the rate of ethylene oxidation to ethylene oxide.
.相似文献
7.
Dependence of excitation energy on the coordination of oxygen atoms in cluster models of MgO surface
Cluster models of the MgO surface have been calculated by a semi empirical method. The energies of transitions between the surface states localized on ions of definite coordination are dependent on their coordination numbers. The lower transition energies correspond to a lower coordination number of oxygen ions.
, . , , , . .相似文献
8.
A. A. Spojakina N. G. Kostova D. M. Shopov 《Reaction Kinetics and Catalysis Letters》1981,17(1-2):83-86
By means of DTA, reflectanc spectra and measurement of catalytic activity in thiophene hydrogenolysis, the effect of support (aluminium hydroxide and oxide) as well as of the order of introduction of molybdenum and cobalt compounds on the structure and catalytic surface of Co–Mo–Al2O3 catalysts is shown.
, ( ) , Co–Mo–Al2O3.相似文献
9.
The oxidation kinetics of ethanol by Ce(IV) has been studied as a function of pH, nitrate and water concentration. Even at high concentration of H+ and NO
3
–
several species appear to exist. The oxidation is fastest in strongly acidic medium without added nitrate ions.
Ce(IV) pH, . H+ NO 3 – , Ce(IV). .相似文献
10.
As a result of computer experiments with model porous networks, the factors (other than pore shape and size distribution) determining the form of the adsorption-desorption hysteresis loop have been elucidated.
, - - .相似文献