共查询到20条相似文献,搜索用时 140 毫秒
1.
Chemical oscillations occur during the uncatalyzed oxidation of a number of phenol and aniline derivatives by acidic bromate.
.相似文献
2.
M. A. Fedotov R. I. Maksimovskaya L. P. Kazanskii 《Reaction Kinetics and Catalysis Letters》1981,16(2-3):185-189
17O,51V and31P NMR studies indicate that the anion structure of sodium vanadophosphate in an aqueous solution is close to that in crystals of the (CN3H6)8HPV14O42 7H2O salt.
17O,51V,31P , (CN3H6)8HPV14O42 7H2O.相似文献
3.
V. V. Shereshovets N. M. Korotaeva Yu. I. Puzin G. V. Leplyanin V. D. Komissarov 《Reaction Kinetics and Catalysis Letters》1990,42(1):39-46
Kinetic regularities in the reaction of triphenyl phosphite ozonide with several thioacetals in CH2Cl2 solution at –15°C have been studied. The consumption rate of ozonides is described by the kinetic equation W=k0[(C6H5O)3P·O3]+k1[(C6H5O)3P·O3][R1R2C(SR3)2] Rate constants k0 and k1 for the thioacetals: (CH3H7S)2CH2, (C6H5S)2CH2, (C6H5CH2S)2CH, (n=C12H25–S)2CH2, (C3H7S)2C(H)CH3, (C3H7S)2C(H)C6H5, (C3H7S)2C(CH3)C6H5 and (C3H7S)2C(H)C10H9, increases with increasing the electron-donating power of subtituents Ri.
CH2Cl2 –15°C. : W=k0[(C6H5O)3P·O3]+k1[(C6H5O)3P·O3][R1R2C(SR3)2] k0 k1 (C3H7S)2CH2, (C6H5S)2CH2, (C6H5CH2S)2CH2, (n-C12H25S)2CH2, (C3H7S)2C(H)CH3, (C3H7S)2C(H)C6H5, (C3H7S)2C(CH3)C6H5, (C3H7S)2C(H)C10H9. .相似文献
4.
T. Kennedy 《Journal of Thermal Analysis and Calorimetry》1970,2(4):379-386
The thermal decomposition of crystalline PI3 and P2I4 in nitrogen and oxygen is reported. The oxidation of PI3 leads mainly to the formation of phosphorus pentoxide and iodine together with PxI polymeric species as a minor product. The decomposition of the polymeric species P3I2O6 in oxygen and nitrogen follows a two-stage route which precludes its involvement in the oxidation of P2I4.
The author is indebted to Mrs. I. M. Walker for practical assistance with the thermoanalysis studies. 相似文献
Zusammenfassung Es wurde die thermische Zersetzung von kristallinem PI3 und P2I4 in Stickstoff und Sauerstoff untersucht. Die Oxydation von PI3 führt zur Bildung von Phosphorpentoxyd und Jod mit wenig Polymeren der Zusammensetzung PxI. Die Zersetzung der Polymeren P3I2O4 in Sauerstoff und Stickstoff erfolgt in zwei Stufen, die eine Beteiligung in der Oxydation von P2I4 ausschließen.
Résumé On décrit la décomposition thermique, dans l'azote et dans l'oxygène, de PI3 et de P2I2 cristallins. L'oxydation de PI3 conduit principalement à la formation d'iode et de pentoxyde de phosphore, avec de petites quantités de PxI de type polymère. La décomposition de l'espèce polymère P3I2O6, dans l'oxygène et dans l'azote, s'effectue suivant un processus en deux étapes excluant sa participation à l'oxydation de P2I4.
I3 P2I4 . I3, , , — — xI . 3I26 , 2I4.
The author is indebted to Mrs. I. M. Walker for practical assistance with the thermoanalysis studies. 相似文献
5.
M. A. Aramendía V. Borau C. Jiménez J. M. Marinas M. E. Sempere F. J. Urbano 《Reaction Kinetics and Catalysis Letters》1992,46(2):325-330
This paper shows the occurrence of a linear relationship between the activation energy (EA) and the logarithm of the pre-exponential factor (ln A) in the Arrhenius equation, and between the enthalpy increment (H) and the entropy increment (S) in the Eyring equation for the reduction of olefinic double bonds by hydrogen transfer over a Pd/sepiolite catalyst. Such a relationship is known as the compensation effect or isokinetic relationship.
Pd/ (Ea) (ln A) (H) (S) . .相似文献
6.
K. Narita N. Takezawa H. Kobayashi I. Toyoshima 《Reaction Kinetics and Catalysis Letters》1982,19(1-2):91-94
With the help of UPS spectroscopy, it has been shown that N2O decomposes into N2 and surface Cu2O over copper catalysts in the temperature range –150, –100°C. The surface oxide oxygen dissolved into the bulk above 100°C to some extent.
, N2O –150° –100°C, N2 Cu2O. 100°C.相似文献
7.
CO hydrogenation on cobalt-rutile and cobalt-anatase catalysts with various amounts of cobalt at 480–570 K has been studied. C1–C15 hydrocarbons are formed on cobalt-rutile catalysts at 478–523 K. During the initial period of catalyst operation a counterclockwise hysteresis is observed. Cobalt-anatase catalysts remain inactive up to 670 K.
CO - - - 480–570 . - 478–523 C1–C15. . - 670 .相似文献
8.
A thermodynamic study is presented for the simultaneous synthesis of C1–C4 alcohols from synthesis gas. The equilibrium composition was calculated for the gaseous mixture containing Co, H2, CH3OH, C2H5OH, C3H7OH, n-C4H9OH and H2O. Operating industrial conditions were specifically considered.
C1–C4 -. , CO, H2, CH3OH, C2H5OH, C3H7OH, -C4H9OH H2O. .相似文献
9.
The hydrogenation of CO2 has been studied at atmospheric pressure on Co/C and Ni/C catalysts and the results are compared with those obtained on unsupported Co and Ni. Specific activites in the form of turnover frequencies for CO2 hydrogenation decrease with increasing metal dispersity. Carbon supported Co and Ni present a smaller selectivity for methane than bulk metals. Higher specific activities and smaller activation energies are obtained on Co catalysts, compared with those determined for Ni catalysts.
CO2 Co/ Ni/ Co Ni . CO2 . Co Ni , . .相似文献
10.
《Reaction Kinetics and Catalysis Letters》1978,8(4):463-468
N2O2+NON2O+NO2. Al2O3 . No+ -. Al2O3 .
The adsorption of NO is accompained by dimerization with subsequent disproportionation N2O2+NON2O+NO2 The NO2 formed gives complex nitrates with the Al2O3 surface. The NO+ ions interacts with hydroxy groups of the adsorbent. The relative amount of various adsorbed forms on Al2O3 depends on the pressure.相似文献
11.
Ming-Sheng Wang Wen-Tong Chen Li-Zhen Cai Guo-Wei Zhou Guo-Cong Guo Jin-Shun Huang 《Journal of Cluster Science》2003,14(4):495-504
The reactions of TMA4Ge4S10 (TMA=tetramethylammonium), Cu(NO3)23H2Oand 4,4-bipy under hydrothermal environment result in the formation of (H2bipy)2Ge4S10(bipy)7H2O (1), which has been structurally characterized by single crystal X-ray analysis. The 3-D structure of 1 can be viewed as an inorganic-organic hybrid supramolecular hydrogen-bonding (hydrogen bonds: O–HO, N–HN, C–HO, N–HO, and O–HS) and - stacking network containing Ge4S4–
10 clusters and novel [H2bipybipyH2bipy] trimers. 相似文献
12.
The process of obtaining a special aluminium oxide by means of the thermal dissociation of a basic aluminium-potassium sulfate in the presence of carbon (soot) and water vapour was studied. Under these conditions, the dissociation of the basic salt occurs at a lower temperature than in presence of air. K2O-Al2O3 and/or Al2O3 are formed as fine-grained reaction residues, depending on the final temperature. The technologically useful range of temperatures for the process was established.
Zusammenfassung Der Herstellungsprozess eines speziellen Aluminiumoxids durch thermische Zersetzung von basischem Kalium-aluminium-sulfat in Gegenwart von Kohlenstoff (Russ) und Wasserdampf wurde untersucht. Unter diesen Bedingungen verläuft die Zersetzung bei tieferer Temperatur als in Gegenwart von Luft, und K2O.Al2O3 und/oder Al2O3 werden als feinkörnige Endprodukte (abhängig von der Endtempeatur) erhalten. Der technologisch günstigste Temperaturbereich für den Prozess wurde ermittelt.
- () . , . , , 2l23 l23 . .相似文献
13.
Thermoanalytical data on six reagents and on their compounds with Zr(IV) are reported. Except for H acid, all reagents were azopyrazolonic derivatives obtained by synthesis. The purpose of this study was to obtain data on the thermal stabilities of the reagents and their zirconium compounds, and to establish the reagent: zirconium: water combination ratio.
Zusammenfassung Thermoanalytische Daten von 6 Reagenzien und deren Verbindungen mit Zr(IV) werden mitgeteilt. Außer H-Säure waren alle Reagenzien durch Synthese erhaltene Azopyrazolon-Derivate. Zweck der Untersuchung war, Daten über die thermische Stabilität dieser Reagenzien und ihrer Zirkonverbindungen zu erhalten und das Verhältnis Reagens: Zirkon: Wasser festzustellen.
. , , - . , : : .相似文献
14.
Differential scanning calorimetry has been applied to derive the fusion enthalpies and entropies of series of mono and dimethylphenols, mono and dichlorophenols, and mono and dinitrophenols.
Zusammenfassung DSC wurde verwendet zur Ermittlung der Schmelzenthalpie und Entropie der Reihen von Mono- und Dimethylphenolen, Mono- und Dichlorphenolen, Mono- und Dinitrophenolen.
- , - , - .相似文献
15.
J. M. Libre Y. Barbaux B. Grzybowska J. P. Bonnelle 《Reaction Kinetics and Catalysis Letters》1982,20(3-4):249-254
Bi2Mo3O12 is a selective oxidation catalyst of propylene into acrolein. Surface potential measurements proved the presence of an equilibrium between gaseous oxygen and the O2– species adsorbed on the surface of the catalyst, under oxygen atmosphere, in the range 538K–673K. This is in accordance with the fact that O2– is a selective oxidation species. An oxygen adsorption mechanism is also discussed.
Bi2Mo3O12 . O–2, , 538–613 . , O–2 . .相似文献
16.
m-Xylene conversion was studied over dealuminated Y type zeolites in hydrogen forms, SiO2 to Al2O3 ratios were varied from 4.86 to 12.95.
- . SiO2/Al2O3 4,86 12,95.相似文献
17.
J. J. Tondeur G. Vandendunghen J. P. Lecroart 《Reaction Kinetics and Catalysis Letters》1980,15(1):31-40
Condensation of triphenylsilane with isopropanol in presence of isopropoxide has been studied in anhydrous medium and the activation parameters have been measured. Dehydration of the medium has been obtained by means of a pre-reaction of triphenylsilane with the residual water in the solvent. In this medium the reaction is extremely slow, moreover, it is inhibited by silanol whose effect would lower the actual catalyst concentration.
. . , .相似文献
18.
T. Bérces 《Reaction Kinetics and Catalysis Letters》1977,7(4):379-385
The equation
is suggested for predicting triplet repulsion energies. X=R–Ro, while Ro and1Vo are the equilibrium bond length and the spectroscopic dissociation energy, respectively. Parameters and may be estimated from known bond properties.
( X=R–Ro, a Ro 1Vo , . , .相似文献
19.
Zusammenfassung Unter Anwendung der thermochemische Methode werden die Bestimmungen von SiO2, Al2O3, Na2O, SO3 und Feuchte in feindispersen Kieselsäuren und Silikaten beschrieben. Besonders eingegangen wird auf die aufeinanderfolgende Bestimmung von SiO2 und Al2O3 sowie der hierbei beobachteten Vorteile und Störungen. Über die Möglichkeit der Verwendung der kinetisch-katalytischen Analyse mit thermometrischer Indikation zur Bestimmung von Cu und Mn werden Ausführungen gemacht. Der zweite Teil des Vortrages befaßt sich mit der Benetzungs- und Immersionswärme von feindispersen Kieselsäuren und Angaben zur Bestimmung dieser auch unter betriebsanalytischen Bedingungen. Für verschiedene Kieselsäuretypen werden unterschiedliche Benetzungswärmen gefunden. Auf die Notwendigkeit der Weiterführung solcher Messungen wird verwiesen.
Überarbeitete Fassung einer Vorlesung zum 3. Seminar über thermometrische Analyse, Marienbad, CSSR, 1983. 相似文献
The authors describe the determination of the SiO2, Al2O3, Na2O, SO3 and moisture contents of finely dispersed silicic acids and silicates by means of thermochemical methods. Special interest is paid to the determination of SiO2 and Al2O3 as well as to the advantages of the method and to disturbing factors. The possibility of using kinetic-catalytic analysis with thermometric end-point detection for Cu and Mn determination is discussed. In the second part of the paper the authors deal with the heat of wetting and heat of immersion of finely dispersed silicic acid, and give data for their determination under circumstances of industrial analysis too. Differences in the heats of wetting were found for the different types of silicic acid. These studies require further measurements to be made.
, , , . , . . . . .
Überarbeitete Fassung einer Vorlesung zum 3. Seminar über thermometrische Analyse, Marienbad, CSSR, 1983. 相似文献
20.
J. Zsakó J. Sztatisz Á. Czégeni G. Liptay Cs. Várhelyi 《Journal of Thermal Analysis and Calorimetry》1987,32(2):463-470
Ten metal and ammonium salts of the acid H2[ReCl6] were obtained by double decomposition reactions, and their pyrolyses in air atmosphere were studied by means of DSC measurements. The kinetic parameters of these reactions were derived and are discussed.
Zusammenfassung 10 Metall- und Ammoniumsalze der Säure H2[ReCl6] wurden durch Doppelzersetzungsreaktionen erhalten. Die Pyrolyse dieser Salze in Luft wurde mittels DSC untersucht. Die kinetischen Parameter dieser Reaktionen wurden ermittelt und diskutiert.
H2[ReCl6]. . .相似文献