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1.
C. Karunakaran K. Ganapathy P. Ramasasamy 《Reaction Kinetics and Catalysis Letters》1989,40(2):369-374
The perborate oxidation of quinol in aqueous acetic acid is first order with respect to perborate, zero order with respect to quinol, and first order with respect to H+. The oxidation is faster than H2O2 oxidation. Breakdown of protonated perboric acid is suggested as the rate-limiting step.
, H+. . , , , .相似文献
2.
I. Paseka 《Reaction Kinetics and Catalysis Letters》1979,11(1):85-89
By comparison of the catalytic hydrogenation and electrochemical reduction of NO on platinum black catalysts it has been shown that the hydrogenation of NO to ammonia and to hydroxylamine occurs in the diffusion controlled region only.
NO , NO .相似文献
3.
Electron paramagnetic resonance studies on intermediates and final active catalyst material used for partial oxidation of anthracene to anthraquinone are reported.
, .相似文献
4.
L. Patyi V. I. Tsarev A. V. Krylova D. Oravets Zs. Farkas N. S. Torocheshnikov 《Reaction Kinetics and Catalysis Letters》1979,12(2):165-170
The surface topography and elemental composition of the near-surface layers of a reduced passivated catalyst for ammonia synthesis have been studied on a scanning electron microscope in the initial state and after high-temperature oxygen treatment as well as removal of the alkali promoter.
CA-IB , .相似文献
5.
A. S. Kharitonov G. I. Panov G. K. Boreskov E. M. Moroz 《Reaction Kinetics and Catalysis Letters》1980,15(2):263-268
It has been found that calcium nitride possesses a high catalytic activity in the isotope exchange of nitrogen. The catalytic activity of nitrides is shown to be independent of the heat of their formation. The effect of H2 and O2 on the isotope exchange of nitrogen is studied.
. . H2 O2 .相似文献
6.
A. N. Drobinin G. N. Kuzmin Yu. P. Solonitsyn 《Reaction Kinetics and Catalysis Letters》1982,21(3):289-293
The capacity of ZnO with respect to the photo- and X-ray adsorbed, as well as postadsorbed oxygen is shown to depend on the temperature. It is suggested that this dependence cannot be attributed to either the thermal annealing of the induced sites or the thermal desorption of the adsorbed molecules.
O , - , , , . , .相似文献
7.
The thermal investigation of the reaction taking place between dichromates and oxalates in the solid state has been done taking two systems of potassium dichromate-potassium oxalate and sodium dichromate-sodium oxalate. The techniques employed include thermogravimetry, differential thermal analysis, infrared spectroscopy and X-ray diffraction studies. The results indicate a stoichiometric reaction of dichromate and oxalate in 11 ratio to give the corresponding chromate as the sole product.
Zusammenfassung Anhand der Systeme Kaliumdichromat-Kaliumoxalat bzw. Natriumdichromat-Natriumoxalat wurde eine thermische Untersuchung der Festkörperreaktion zwischen Dichromaten und Oxalaten durchgeführt. Dazu wurden thermogravimetrische, dififerentialthermoanalytische, IR-spektroskopische und Röntgendiffraktionsverfahren angewendet. Im Ergebnis zeigte sich eine stöchiometrische Reaktion von Dichromat und Oxalat im Verhältnis 11, die das entsprechende Chromat als einziges Produkt liefert.
, , — — . , 11 .相似文献
8.
A new Ru–Co–Mo/Al2O3 catalyst has been prepared by impregnation of Ru salt as a secondary promoter onto Co–Mo/Al2O3 catalyst, and it was found that the Ru–Co–Mo/Al2O3 exhibited higher activity than Co–Mo/Al2O3 in hydrodesulfurization of thiophene to hydrocarbons. Ir studies on Ru–Co–Mo/Al2O3 revealed that the Co and NO adspecies increased significantly in intesnities and displayed a bathochromic shift in frequencies, as compared with Co–Mo/Al2O3.
Ru–Co–Mo/Al2O3 Ru, , Co–Mo/Al2O3. Co–Mo/Al2O3. CO NO, Co Mo, Co–Mo/Al2O3. , Mo , Mo3+ Mo3+ Co Ru–Co–Mo/Al2O3.相似文献
9.
Conversion of paraffins on TsVK and Y zeolites follow a similar mechanism yielding the same intermediates. Low selectivity of Y zeolites with respect to aromatic hydrocarbons is attributed to the strong adsorption of these hydrocarbons on zeolites. It is assumed that the centers of strong adsorption are Al3+ ions in cationic positions in zeolite.
, . . , Al3+ .相似文献
10.
The thermal decomposition of MgCl2·6H2O (non-dried and partly dried) and the kinetics of the process were studied by DTA, TG, DTG, IR, X-ray diffraction and chemical analysis of Mg and Cl. The reactions which occurred in the course of the thermal analysis were identified as dehydration (in steps), thermal hydrolysis of MgCl2·H2O and dehydrochloridization of magnesium hydroxy chlorides. Melting of the phases MgCl2·6H2O, MgCl2·4H2O and MgCl2 was also identified in the thermal curves. Thermal weight loss continued up to 800 °C in flowing air or nitrogen, but only up to 700 °C in static air. MgO was the end-product of thermal treatment in both cases.The kinetic parameters of the reaction, the activation energyE, pre-exponential factorA and apparent order of reactionb, were computed by several methods. The activation energy and the apparent reaction order of dehydration were found to increase with decreasing hydration number of the Mg. The dehydrochloridization process had the highest activation energy.
The authors express their appreciation to Dr. Jacob Nathan and Mr. Yoetz Deutch from th Geological Survey, Jerusalem, for the use of the thermal analysis instrument and for useful discussion, and to Mrs. Sarah Erlich from the same institute, for the chemical analysis. The financial support by Everyman's University, Tel-Aviv, and by the Hebrew University of Jerusalem is acknowledged. 相似文献
Zusammenfassung Die thermische Zersetzung von MgCl2·6H2O (nicht und teilweise getrocknet) und die Kinetik dieses Prozesses wurden mittels DTA, TG, DTG, IR, Röntgendiffraktometrie und chemischer Analyse von Mg und Cl untersucht. Die im Verlaufe der thermischen Analyse vor sich gehenden Reaktionen sind Dehydratisierung (in Schritten), thermische Hydrolyse von MgCl2·H2O und Chlorwasserstoffaustritt aus Magnesiumhydroxychloriden. Das Schmelzen der Phasen MgCl2·6H2O, MgCl2·4H2O und MgCl2 ist in den thermischen Kurven ebenfalls zu erkennen. Im Luft- und Stickstoffstrom erfolgt ein Gewichtsverlust bis 800 °C, in statischer Luftatmosphäre dagegen nur bis 700 °C. MgO war in beiden Fällen Endprodukt der thermischen Behandlung. Die kinetischen Parameter der Reaktion (AktivierungsenergieE, präexponentieller FaktorA, scheinbare Reaktionsordnungb) wurden nach verschiedenen Methoden berechnet. Aktivierungsenergie und scheinbare Reaktionsordnung der Dehydratisierung nehmen mit abnehmendem Hydratationsgrad des Mg zu. Die Chlorwasserstoffabspaltung erfordert die höchste Aktivierungsenergie.
, , , , ( ) . : ( ), . , . 800 °C, - 700 °C. B . , . , . .
The authors express their appreciation to Dr. Jacob Nathan and Mr. Yoetz Deutch from th Geological Survey, Jerusalem, for the use of the thermal analysis instrument and for useful discussion, and to Mrs. Sarah Erlich from the same institute, for the chemical analysis. The financial support by Everyman's University, Tel-Aviv, and by the Hebrew University of Jerusalem is acknowledged. 相似文献
11.
V. Yu. Mashkin I. V. Desyatov A. V. Mashkina 《Reaction Kinetics and Catalysis Letters》1992,47(1):119-123
Kinetic studies of tetrahydrofuran reaction with H2S were carried out in a flow-circulation reactor. Presumably, the reaction takes place through dissociative chemisorption of reactants and the interaction of surface structures formed to produce thiolane and water. A kinetic equation that agrees with the suggested mechanism has been derived.
- H2S. , . , .相似文献
12.
N. N. Bulgakov V. F. Anufrienko V. V. Zakharov 《Reaction Kinetics and Catalysis Letters》1989,40(2):221-225
By using the interacting bonds method (IBM), it has been established that for the chloride Ziegler systems (TiCl4+AlR3) for polymerization the formation of Ti
2
7+
and Ti
2
6+
pairs is a thermodynamically favorable process.
(TiCl4+AlR3) () , Ti 2 7+ Ti 2 6+ .相似文献
13.
J. Zsakó Cs. Várhelyi G. Liptay A. Borbély-Kuszmann 《Journal of Thermal Analysis and Calorimetry》1986,31(2):285-295
Twelve new complexes NH4[Co(DH)2(SO3)(amine)]·t H2O (DH
2=dimethylglyoxime) have been synthesized and characterized. Their i.r. spectra show the SO3 to be co-ordinated to the Co atom through the S atom. The thermal decompositions of a series of derivatives of this type have been investigated with a derivatograph. The first process is an endothermic dehydration reaction, occurring in a single stage or in two successive ones. The loss of the crystallization water is followed by another endothermic reaction, without a clear stoichiometry, which is referred to as deamination. At higher temperatures, exothermic pyrolysis processes occur. From the TG curves, kinetic parameters have been derived for the dehydration and deamination reactions.
Zusammenfassung Zwölf neue Komplexe der allgemeinen Formel NH4[Co(DH)2(SO3)(amin)]·t H2O (DH=Dimethylglyoxim) wurden synthetisiert und charakterisiert. Die IR-Spektren zeigen, daß SO3 über das S-Atom koordinativ an das Co-Atom gebunden ist. Die thermische Zersetzung einer Reihe von Derivaten dieses Typs wurde mittels eines Derivatographen untersucht. Der erste Prozeß ist die in einem einzigen oder in zwei aufeinander folgenden Schritten verlaufende endotherme Dehydratisierung. Auf die Abgabe des Kristallwassers folgt eine andere endotherme Reaktion unklarer Stöchiometrie, die als Deaminierung bezeichnet wird. Bei höheren Temperaturen verlaufen exotherme Pyrolyseprozesse. Aus den TG-Kurven wurden kinetische Parameter für die Dehydratisierung und die Deaminierung bestimmt.
NH4Co(DH)2(SO3)(a)]·tH2O, DH 2 — . , . . , . «». . .相似文献
14.
T. López A. Romero A. Chavela L. Razo R. Gómez 《Reaction Kinetics and Catalysis Letters》1991,43(2):307-312
-Al2O3 was synthesized from trisec-butoxide by the sol-gel method. pH was varied during reaction and solvents of different polarity were used. Solids with specific areas, greater than 200 m2/g, were obtained, which depend directly on the reaction parameters.
-Al2O3 - -. . pH . , 200 2/ .相似文献
15.
A. N. Startsev O. V. Klimov S. A. Shkuropat 《Reaction Kinetics and Catalysis Letters》1990,41(1):121-125
A new method of preparation of highly active catalysts for metathesis of -olefins through the anchoring of [Mo2O4(C2O4)2(H2O)2]2– anion to the surface of -Al2O3 with further thermal activation in H2 and CO is proposed.
- [Mo2O4(C2O4)2(H2O2]2– -Al2O3 H2 CO.相似文献
16.
V. A. Gruznykh F. K. Shmidt V. V. Saraev M. V. Ustinov 《Reaction Kinetics and Catalysis Letters》1987,33(1):17-21
ESR studies of the interaction between Co(C5H7O2)2 and Al(C2H5)3 in presence of CO reveal the formation of paramagnetic tri- and tetra-nuclear carbonyl compounds and the consecutive formation of complexes including one, two and three cobalt atoms. Al(C2H5)3 decomposition is suggested to take place on the reduced transition metal to form Co–Al clusters. Structures for the paramagnetic heteronuclear clusters is proposed.
- . - . , , . , - -. .相似文献
17.
E. N. Yurchenko O. G. Korolkova N. G. Zubritskaya 《Reaction Kinetics and Catalysis Letters》1991,44(1):215-222
IR spectroscopic and kinetic studies of the interaction between basic carbonates of Cu and Ni and H2CrO4 allows to suppose that catalyst formation is affected by different structures of the initial substances. The formation of mixed Ni–Cu–Cr phases is observed during the step of chromate formation and is preserved after treatment by ammonium.
Cu Ni H2CrO4. , . Ni–Cu–Cr- .相似文献
18.
The thermal stabilities of poly(-bromostyrene), poly-(methyl methacrylate) homopolymers and copolymers of-bromostyrene-methyl methacrylate covering the entire composition range were studied using TG analysis. At each extreme of the composition range, incorporation of comonomer units results in a copolymer more stable than the brominated homopolymer. Maximum stability occurs for compositions of approximately 62 mole percent-bromostyrene. The formation of the anhydride structure among the degradation products leads to the stability of the copolymers.
Presented at the World Conference of Thermal Analysis, held in Bad Hofgastein (Austria), 1985. 相似文献
Zusammenfassung Die thermische Stabilität von-Bromstyrol- und Methylmethacrylat-Homopolymeren sowie von sich über den ganzen Zusammensetzungsbereich erstreckenden-Bromstyrol/Methylmethacrylat-Kopolymeren wurde thermogravimetrisch untersucht. An beiden Enden des Zusammensetzungsbereichs führt der Einbau von Komonomereinheiten zu einem Kopolymer, das stabiler als das bromierte Homopolymer ist. Maximale Stabilität wird bei einem Gehalt von etwa 62 Mol-%-Bromstyrol erreicht. Die Bildung der Anhydridstruktur führt zur Stabilität des Kopolymers.
/-, - . , . - 62%. .
Presented at the World Conference of Thermal Analysis, held in Bad Hofgastein (Austria), 1985. 相似文献
19.
J. C. Volta W. Desquesnes B. Moraweck G. Coudurier 《Reaction Kinetics and Catalysis Letters》1979,12(3):241-246
Oriented MoO3-graphite catalysts were prepared by oxyhydrolysis of a MoCl5-graphite intercalation compound and used in catalytic oxidation of propylene. Results show a correlation between the building of specific crystal faces of MoO3 and a selectivity towards acrolein formation.
MoO3- -MoCl5- - . MoO, - .相似文献
20.
Hydrogen desorption proceeds in several temperature regions and differs by its order of magnitude and activation energy. Differential curves of adsorbed hydrogen distribution with respect to the desorption activation energy, dN/dE (E), show a considerable inhomogeneity of adsorbed atomic species and the energetic homogeneity of molecular species.
. dN/dE (E) .相似文献