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101.
102.
Yatsimirskii V. K. Oleksenko L. P. Lutsenko L. V. 《Theoretical and Experimental Chemistry》2004,40(1):44-51
We have studied the kinetic behavior of oxidation of carbon monoxide on Co-containing zeolite ZSM-5. We have shown that the kinetic curves obtained for the dependence of the reaction rate on the reagent concentration can be described by an Eley–Rideal mechanism, which assumes that oxygen can be adsorbed on the surface of the catalyst in both atomic and molecular form, followed by reaction of CO from the gas phase with the adsorbed oxygen. 相似文献
103.
V. V. Nedel'ko B. L. Korsounskii T. S. Larikova V. R. Stepanov N. V. Chukanov I. V. Nedel'ko 《Russian Chemical Bulletin》1994,43(11):1812-1815
The thermal decomposition of 1-ethyl-5-iodotetrazole in a melt and in solutions was studied using thermogravimetry, manometry, pyrolytic mass spectrometry, and IR spectroscopy. The kinetic and activation parameters of the process and the nature of the decomposition products were determined. The reaction mechanism is assumed to involve equilibrium tautomeric rearrangement of the tetrazole to azidoazomethine form followed by homolytic cleavage of the C-I bond.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1923–1926, November, 1994.The authors are grateful to O. A. Ivashkevich and P. N. Gaponic (Belarussian State University), who provided the samples of the tetrazole. 相似文献
104.
The synthesis of malachite CuCO3·Cu(OH)2 or Cu2CO3(OH)2 was studied through titrations of copper(II) salt solutions with a solution of sodium carbonate at different temperatures. The precipitates were characterized by TG, IR and chemical analysis. The composition varies depending on thepH of the solution and the temperature. Purer malachite was synthesized by simple mixing of a solution of copper(II) nitrate or sulfate with a solution of sodium carbonate at 50°C.The kinetics of the thermal decomposition of synthetic malachite was described by eitherR
3 orA
m(m=1.2–1.4) law, according to TG analysis, both isothermal and nonisothermal. The Arrhenius parameters determined using three different integral methods showed the kinetic compensation effect, which is correlated to the working temperature interval analyzed.The authors thank Mr. H. Takemoto for analyzing kinetics of the thermal decomposition of synthetic malachite. 相似文献
105.
用DSC研究纯三水铝石溶出动力学 总被引:1,自引:0,他引:1
在DSC上研究了NaOH溶液中合成三水铝石的溶出过程动力学。应用非等温反应动力学模型计算了动力学参数,分析和确定了反应机理。模型计算结果与用DSC测得的结果吻合。 相似文献
106.
[H+]在0.01~0.70mol?L-1范围内,离子强度为1.00mol?L-1,[Fe(III)]>>[配体]、[H+]>>[配体]的条件下,研究了Fe(III)与2,3-二羟基苯磺酸钠(Tiron)的配位反应.发现当[H+]≤3.00×10-2mol?L-1时,[Fe(III)]2对反应速率有明显的贡献.求得了相关反应的动力学参数,从而揭示了FeOH2+和FeOH24+与Tiron配位的解离反应途径及FeOH32+的缔合反应机制,并提出了该配位反应的可能机理. 相似文献
107.
O. F. Shlensky 《Journal of Thermal Analysis and Calorimetry》1993,40(3):941-947
New modifications of a contact heater are suggested for investigating thermal decomposition processes, as well as for determining
kinetic characteristics of substances under conditions of intense heating to a fixed constant temperature.
Zusammenfassung Zur Untersuchung von thermischen Zersetzungsprozessen und der Bestimmung der Reaktionskinetik von Substanzen bei intensivem Erhitzen auf vorgegebene konstante Temperaturen wird eine neue Abart von Kontakterhitzern beschrieben.相似文献
108.
Relationships between average degree of transformation and time of dissociation were derived for polydisperse granular materials
with account to the type of grain size distribution. It has been checked, under what conditions the kinetic curves obtained
by numeric solution of those relationships may be described in terms of equations D1 α2=kt
, F2 [1/(1 - α) - 1 =kt] and F3 [1/(1 - α)2 - 1=kt].
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
109.
Bagiyan G. A. Koroleva I. K. Soroka N. V. Ufimtsev A. V. 《Russian Chemical Bulletin》2003,52(5):1135-1141
Side self-oxidation of thiols was studied. It was found that these reactions in neutral and alkaline solutions are induced by impurities of variable-valence metals. The ability of transition metals to catalyze oxidation of thiols changes in the order Cu > Mn > Fe > Ni Co. The plot of the self-oxidation rate vs. pH passes through a maximum whose position on the pH scale depends on both the nature of metal and the structure of the thiol oxidized. For thiols having different structures, the kinetic orders in reactions catalyzed by copper ions differently vary with pH, which is apparently associated with the formation of complexes possessing different catalytic activity. 相似文献
110.
A thermal analysis study on the reduction of iron oxide rich slags under different conditions is presented in this paper. The effects of important process variables such as time, temperature, lime-silica ratio, FeO level in slag etc. are discussed. It is shown that the mechanism of reduction by externally added graphite is different from that by a carbon saturated bath although the activation energy values are similar. 相似文献