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1.
The conversions of 1-methylnaphthalene on NaY zeolite and its magnesium modifications with different degrees of ion exchange and various Si/Al ratios have been studied at 310 and 350 °C. The investigated catalysts are highly active for positional isomerization. The observed changes in their catalytic activity are explained by the promotion of proton formation and by the absorption properties of magnesium cations as well as by their localization in cations as well as by their localization in the crystal lattice of the zeolite.
1- NaY Si/Al 310 350°C. . , .
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2.
Crystalline Ru3(CO)12 and Fe3(CO)12 carbonyl clusters were deposited on a Cu sample holder and core level binding energies (BE) for O 1s, C 1s Fe 2p 3/2, Fe 2p 1/2, Ru 3d 5/2 and Ru 3d 3/2 were measured before and after decomposition. Part of the carbonyl clusters remained in the original form even at a pressure of 10–5 Pa, indicated by a Fe satellite peak and high BE for C 1s. After decomposition, carbon is partly retained by iron, whereas the twin peak at Ru 3d 5/2 and Ru 3d 3/2 show no carbon left on the ruthenium surface.
Ru3(CO)12 Fe3(CO)12 (BE) O 1S, C 1S, Fe 2p 3/2, Fe 2p 1/2, Ru 3d 5/2 Ru 3d 3/2 . 10–5 Pa, Fe BE 1S. , Ru 3d 5/2 Ru 3d 3/2 , .
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3.
Adsorption capacities of zeolites are rapidly determined by a vapor sorption apparatus which can be used as an ultramicroporosimeter. From the sorption data, it is possible to calculate the zeolite affinities toward various adsorbates in comparison with water. The n-hexane affinity index of the new ZSM zeolites has values always higher than those of X, Y or Zeolon zeolites. This fact is attributed to the unusual framework structure of the silica-rich ZSM zeolites.
, . . - ZSM , X, Y . ZSM , .


Presented in part at the I0 Convegno nazionale di Catalisi-II0 Simposio Italo/Cecoslovacco di Catalisi, held in Bologna (Italy) on June 1979.  相似文献   

4.
The title reaction was studied in aqueous hydrochloric acid at high iodide concentations. The reaction is first order with respect to both oxidant and substrate though diisonicotinoyl hydrazines are the products apart from nitrogen. The reaction is markedly inhibited by H+ and I ions. An I ion independent path is also noticed.
. , , -() , . H+ I. , , I.


Part II: Indian J. Chem. (In press)  相似文献   

5.
Excess molar enthalpies,H E , at atmospheric pressure and 303.15 K are reported for binary mixtures of 1-chlorohexane with diethyl oxalate, diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl pimelate and diethyl sebacate. These experimental results, together with those obtained previously on the excess enthalpies of aliphatic diester+n-hexane mixtures, are interpreted in terms of molecular surface interactions between aliphatic, chlorinated and carboxylate groups. Comparison of the enthalpy interchange parameters reveals a decrease of the intermolecular interactions with decreasing intramolecular COO-COO distance in the diester molecule.
Zusammenfassung Bei Atmosphärendruck und 303,15 K gemessene molare Überschußenthalpien (H E werden für binäre Gemische von 1-Chlorhexan mit Diäthyloxalat, Diäthylmalonat, Diäthylsuccinat, Diäthylglutarat, Diäthyladipat, Diäthylpimelat bzw. Diäthylsebacat angegeben. Diese experimentellen Ergebnisse werden zusammen mit den früher für Gemische von aliphatischen Diestern und n-Hexan erhaltenen Resultaten als molekulare Oberflächenwechselwirkungen zwischen aliphatischen, chlorierten und Carboxylatgruppen interpretiert. Ein Vergleich der Enthalpieaustauschparameter läßt eine Verminderung der intermolekularen Wechselwirkungen mit abnehmendem intramolekularem Abstand zwischen den COO-Gruppen erkennen.

(H E ) 303,15 K 1- , , , , , . , + -, , . COO-COO .
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6.
Polymer compositions based on furyl alcohol and polyamic acid were investigated by using mass-spectrometric thermal analysis. It was established that polyamic acid catalyses both the polycondensation of furyl alcohol and the formation of a three-dimensional network of furan polymer.
Zusammenfassung Mittels massenspektroskopischer Thermoanalyse wurden auf Furylalkohol und Polyamidsäure basierende Polymergemische untersucht. Es wurde festgestellt, daß Polyamidsäure sowohl die Polykondensation von Furylalkohol als auch die Bildung eines dreidimensionalen Furanraumnetzes katalysiert.

- . , , .
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7.
K4Fe(CN)6·3H2O was studied by a derivatograph in the temperature range +20° to +300° and dielectric constant () measured from –80° to +150°. The loss of the three water molecules occurs at 105° and the vs T curve shows a Debye relaxation behavior. By using Mason's theory it was possible to classify K4Fe(CN)6·3H2O in the temperature range –25° to +100° C as a para-electric order-disorder crystal.
Zusammenfassung K4[Fe(CN)6].3 H2O wurde mit dem Derivatograph im Temperaturbereich von+20° bis+300° untersucht und die dielektrische Konstante () im Bereich von –80° und +150° gemessen. Die Abspaltung der drei Wassermoleküle erfolgt bei 105°. Die Kurve von als Funktion vonT zeigt ein Relaxationsverhalten nach Debye. Bei Anwendung der Theorie von Mason gelang es K4[Fe(CN)6].3 H2O im Temperaturbereich von –25° bis 100° als para-elektrischen, geordneten-ungeordneten Kristall einzuordnen.

Résumé Etude de K4Fe(CN)6·3H2O à l'aide d'un «Derivatograph» entre +20 et +300° mesure de la constante diélectrique () entre –80 et+150°. La perte des trois molécules d'eau a lieu à 105° et la courbe en fonction deT montre un comportement de relaxation Debye. D'après la théorie de Mason, il est possible de classer K4Fe(CN)6·3H2O comme cristal paraélectrique ordre-désordre entre –25 et +100°.

K4[Fe(CN)6] · 3H2O +20° +300° –80° +150°. 105°, -T . , , K4[Fe(CN)6] · 3H2O –25° +100° .


Work partially supported by Banco Nacional de Desenvolvimento Econômico and Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul.

P. da R. Andrade deceased on December 16, 1974.  相似文献   

8.
Methane adsorbed on MgO is activated to form CH3 fragments stabilized on cations and OH groups.
, MgO CH3-, OH-.
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9.
Acidic behavior of ZnO is observed in spectroscopic experiments (Zn–H band at 1708 cm–1, XPS O 1s binding energy 530/532 eV, pyridine Lewis band at 1452 cm–1), basic behavior in catalytic reactions of alcohols (98% dehydrogenation). This is ascribed to a high sensitivity to experimental conditions.
ZnO ( Zn–H 1708 –1, XPS O 1s 530/532 .., 1452 –1), (98% ). .
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10.
According to results obtained previously for the linear equations of chemical kinetics, the relation between the steady-state reaction rate and the relaxation time has been studied.
, , .
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11.
An analysis of the correlation suggests that the common stages in photosorption, photooxidation and photodecomposition of some simple molecules on alkali metal halides are connected with catalyst photoexcitation.
, , , .
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12.
Kinetic studies of hydrogen and carbon monoxide adsorption on reduced Re2O7/Al2O3 catalysts have revealed that its activation energy decreases with increasing reduction degree of rhenium oxide. Adsorption of gases is suggested to take place on metallic rhenium atoms.
- . , . , .
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13.
For measuring relative rate coefficients of OH-radical reactions in organic media a competitive method has been used. As reference, 2-propanol was applied. For ethylbenzene and 1-phenylethanol the rate coefficients of H-abstraction relative to that of 2-propanol are 1.4 and 2.9, respectively.
OH. 2-. H 1-, 2-, 1,4 2,9, .
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14.
From the analysis of the detailed reaction mechanism and taking into account vanadium complex formation processes, a steady state kinetic equation has been derived to describe experimental data in a wide range of reaction conditions.
, .
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15.
A considerable amount of adsorbed oxygen species is formed by the reaction of N2O on CaO. It is suggested that these adsorbed species were practically held on 5-coordinated sites.
- N2O CaO. , 5-- .
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16.
Catalysts containing trimethylsilyl complexes of V(IV) and (III) supported on SiO2 and Al2O3, have been synthesized and examined for ethylene polymerization. The state of vanadium in solution and on the support and catalysts interaction with C2H4, CO, H2 and pyridine have been studied using ESR and IR spectroscopy.
, (IV) (III), SiO2 Al2O3. , C2H4, CO, H2 .
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17.
Relative hydrogenation reactivity of the two carbonyl groups of methylcyclohexane-1,4-dione can be estimated beside that of two related compounds, 2- and 3-methyl-cyclohexanones. The reaction is accompanied with hydrogenolysis on Pt and Pd. The less hindered 4-carbonyl group is selectively hydrogenolyzed.
-1,4- , 2- 3-. Pt Pd. 4- .
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18.
The adsorption properties of Pt-black reduced in various solvents (water, sulfuric acid, ethanol, alkali, heptane) have been studied. The nature of solvent is shown to influence the catalyst surface formation, the heat of hydrogen adsorption and the ratio of its forms.
Pt-, : , , , , . , , .
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19.
The presence of hydrogen sulfide and oxygen in mixtures increases the number of sites for dissociative desorption on the surface of MoS2 as compared with the adsorption of individual hydrocarbons. This phenomenon can be explained by a change in the coordination state of the active sites (molybdenum ions) upon the adsorption of the gases mentioned.
, MoS2 . .
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20.
Abstract A series of rare earth transition metal perovskites has been synthesized and the catalytic activity tested for 2-propanol decomposition. The effect of rare earth ions on the catalytic activity can been understood from the correlations obtained between the physico-chemical properties and the catalytic activity of the perovskites.
, , 2-. , - .
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