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1.
《Reaction Kinetics and Catalysis Letters》1978,8(1):29-34
23° - , (–1)/(2+1) 1/, ET . , (–1)/(2+1), — ET .
The correlation between the rate of gamma-initiated isosafrole oxidation and the rate of radiation-chemical initiation has been studied together with the dependence of the oxidation rate on (–1)/(2+1) and 1/ as well as on ET of the solvent at 23°C. It has been shown that the logarithm of the rate of free-radical oxidation is a linear function of (–1)/(2+1) and that of the ionic process depends linearly on ET of the solvent.相似文献
2.
Catalytic behaviour of Mo-based catalysts in liquid phase epoxidation of propylene by hydroperoxides
The activity of different Mo-based catalysts in propylene epoxidation by t-BuO2H was investigated. MoO2(C13H10O2N)2 and MoO2 (oxine)2 gave quantitative yields in propylene oxide; other compounds were inactive and MoO2 (acac)2 was less active and selective.The different catalytic behaviour of these catalysts is attributed to the different strength of Mo-ligand bonds.
t-BuO2H. MoO2 (C13H10O2N)2 MoO2 ()2 ; , MoO2 (acac)2 . Mo-.相似文献
3.
Generation of gradientless conditions by the pulsation method with variable reciprocating gas flow method through the isothermal catalyst bed is suggested as one of the trends in the further development of external circulation flow systems. The conditions ensuring continuous stirring have been established. Flowcirculation and pulsation methods have been tested under similar conditions.
- - . , , - .相似文献
4.
S. V. Bogdanov A. P. Shepelin V. I. Kovalchuk E. M. Moroz P. A. Zhdan Yu. A. Ryndin B. N. Kuznetsov Yu. I. Yermakov 《Reaction Kinetics and Catalysis Letters》1980,14(2):233-238
The V–Ti–O system as a product of thermal decomposition of vanadyl and titanyl oxalates at 873 and 1173 K in argon atmosphere was studied by X-ray diffraction and infrared spectroscopy. The results obtained, the analysis and surface measurement data suggest that a V3+–V4+–Ti4+–O solid solution is formed. Spectroscopic measurements reveal the presence of a V=O bond in the system obtained at 873 K.
V–Ti–O, 873 1173 - . , , V+3–V+4–O . V=O , 873 .相似文献
5.
I. M. Tsvetkov G. B. Maravin S. V. Lymar V. N. Parmon 《Reaction Kinetics and Catalysis Letters》1984,25(1-2):95-99
A peculiarity of the photocatalytic action of porphyrin molecules with different localization inside lipid bilayers of lecithin vesicles has been studied. The influence of an electrostatic field in the lipid membrane on the efficiency of electron photocatalytic transfer across the membrane is discussed.
, - . . .相似文献
6.
G. V. Ratovskii T. V. Dmitrieva L. O. Nindakova F. K. Shmidt 《Reaction Kinetics and Catalysis Letters》1979,11(2):121-124
The Al(acac)3/Et2Al(acac) ratio depends on the Al/Co and the solvent. The solvent contains Et2Al(acac) as a dimer, which is stabilized in the presence of Co(O) and arenes. The role of Et2Al(acac) dimer in the formation of active Co(O) complexes is discussed.
, Al(acac)3/Et2 Al(acac) Al/Co . (Et2Al(acac) Co(O) . Et2Al(acac) Co(O).相似文献
7.
J. V. Sinisterra F. Garcia-Blanco M. Iglesias J. M. Marinas 《Reaction Kinetics and Catalysis Letters》1985,27(2):263-267
In order to determine the nature of active sites that act in the Michael addition of ethyl malonate to chalcone in EtOH, catalyzed by activated barium hydroxide, selective poisoning experiments have been carried out. It has been found that the catalytic activity of the C-200 catalyst is related to the strong basic sites titrated by TBMPHE.
, - . , C-200 - , TBMPHE.相似文献
8.
J. Tóth 《Reaction Kinetics and Catalysis Letters》1979,11(4):377-381
In the X-ray diffraction and thermal investigations of a V/Ni=1 catalyst, obtained by calcination of V2O5 and Ni(NO3)2·6H2O, it has been shown that at 600–700 °C a phase characterized by a rather poor crystalline state is formed, in which Ni2V2O7 with smaller amounts of Ni(VO3)2 and Ni3(VO4)2 have been identified.
- V/Ni=1, V2O5 Ni(NO3)2·6H2O, , 600–700°C , , Ni2V2O7 Ni(VO3)2 Ni3(VO4)2.相似文献
9.
J. Simon 《Journal of Thermal Analysis and Calorimetry》1976,10(3):451-460
The development of the multiple thermal methods and the results obtained with them during the past three years are discussed.
The author wishes to express her thanks to Miss Beata Androsits for her valuable help in assembling the material. 相似文献
Zusammenfassung Es wird ein Überblick der vielseitigen thermischen Methoden gegeben und die wesentlichsten in den letzten drei Jahren erzielten Ergebnisse vorgestellt.
Résumé Mise au point sur le développement des méthodes thermiques associées au cours des trois dernières années et discussion des résultats obtenus.
, .
The author wishes to express her thanks to Miss Beata Androsits for her valuable help in assembling the material. 相似文献
10.
Effect of the secondary structure of poly-L-lysine on the adsorption at the water/dodecane interface
The adsorption of poly-L-lysine of different conformation (-helix, -sheet and random coil) at the water/dodecane interface has been studied by interfacial tension measurements using the drop volume method. The experimental adsorption isotherms provide information about a critical aggregation concentration, the maximum interfacial tension depressionmax and the minimum area A occupied by adsorbed molecules at the interface. Differences inmax exist between -helix and -sheet and, moreover, in the area values between random-coil on the one side and -helix and -sheet on the other hand. 相似文献
11.
Summary A high performance liquid chromatographic system has been developed for the resolution of ten anti-inflammatory drugs. Isocratic separation was achieved using a Spherisorb 5m ODS column with an eluent consisting of water-orthophosphoric acid to pH 3.2: acetonitrile: methanol (523513). A comparison was made between chloroform/acetonitrile (32) and hexane/ether (11) as solvents for the extraction of these drugs from serum. 相似文献
12.
M. J. Hernández M. A. Ulibarri J. Cornejo 《Journal of Thermal Analysis and Calorimetry》1986,31(3):633-641
The kinetics of thermal dehydration of [Ni2Al(OH)6]2SO4.nH2O has been studied through the analysis of isothermal weight loss data. The results obtained seem to indicate that the process is governed by a diffusion mechanism up to an value which is dependent on the temperature. An explanation is provided for this behaviour on the basis of the structural properties of the compound and the nature of the water loss.
Zusammenfassung Die Kinetik der thermischen Dehydratisierung von [Ni2Al(OH)6]2SO4.nH2O wurde mittels isothermer TG untersucht. Die Ergebnisse scheinen darauf hinzudeuten, daß der Prozeß bis zu einem von der Temperatur abhängigen -Wert von einem Diffusionsmechanismus bestimmt wird. Für dieses Verhalten wird basierend auf den strukturellen Eigenschaften der Verbindung und der Natur der Wasserabgabe eine Erklärung gegeben.
, [Ni2Al(OH)6]2SO4.nH2O. , , . , .相似文献
13.
The thermal stress around the sodium level of the LMFBR reactor vessel, caused by the axial temperature distribution during heat-up and cool-down transient conditions, is one of the most important problems for a reactor vessel designer, especially in a conceptual design stage. Key parameters relating to plant operating transient conditions and reactor vessel main configuration should be settled carefully, thermal stresses not being allowed to exceed design stress limits. In order to examine the sodium level thermal stress easily and economically, a simple computer program for parameter survey has been developed. This program uses a one-dimensional Fourier series solution in transient temperature distribution analysis, and an analytical stress solution based on shell theory in stress value estimation. This paper presents a simplified and economical calculation method for the axial temperature distribution and stress value in the LMFBR operating transient conditions, and analysis examples obtained with this computer program.
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal) 1986. 相似文献
Zusammenfassung Der durch die axiale Temperaturverteilung während der Übergangsphase von Aufheizen und Abkühlen verursachte thermische Streß rund um den Natriumfüllstand des LMFBR-Reaktorkessels ist für den Reaktorkesselkonstrukteur, besonders im Entwurfstadiuni eines der wichtigsten Probleme. Die mit den transienten Operationsbedingungen der Anlage und der Gestaltung des Reaktorkessels in Beziehung stehenden Grundparameter müssen sorgfältig ermittelt werden, um zu verhindern, daß der thermische Streß die geplanten Streßgrenzen nicht überschreitet. Um den thermischen Streß um den Natriumfüllstand, leicht und ökonomisch zu bestimmen, wurde ein Komputerprogramm für die Parameterübersicht aufgestellt. In diesem Programm wird von einer eindimensionalen Fourrierreihe zur Analyse der transienten Temperaturverteilung und einer auf der Schalentheorie von Streßwertbestimmungen basierende analytische Lösung Gebrauch gemacht. Im vorliegenden Artikel werden eine vereinfachte und wirtschaftliche Berechnungsmethode für die axiale Temperaturverteilung und Streßwerte bei transienten Arbeitsbedingungen mitgeteilt und mit diesem Komputerprogramm ausgeführte Analysenbeispiele angegeben.
, - () , , , . , , , . , , - , . , , .
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal) 1986. 相似文献
14.
O. P. Dmitrieva V. E. Agabekov N. I. Mitskevich 《Reaction Kinetics and Catalysis Letters》1982,19(1-2):139-143
Studies of the initial step of liquid-phase oxidation of 8-pentadecanone catalyzed by chromium stearate (CrSt3) indicate that the catalyst takes part in the formation of free radicals in the interaction of ketone with dissolved oxygen. In chain propagation and termination reactions CrSt3 does not participate.
(CrSt3) 8-. , . CrSt3 .相似文献
15.
R. Vîlcu F. Irinei J. Ionescu-Bujor M. Olteanu I. Demetrescu 《Journal of Thermal Analysis and Calorimetry》1985,30(2):495-502
The thermal behaviour of acrylamide-maleic anhydride copolymers was studied by thermogravimetric (TG and DTG) analysis. The obtained data permitted the calculation of activation energies and reaction orders of the decomposition steps by the Coats-Redfern and Freeman-Carroll methods.Thermal analysis shows four distinct peaks in the case of polyacrylamide and AAMA (71) copolymer and only three for AAMA (11) copolymer.In AA:MA (11) copolymers intermolecular imidization occurs only and thermal degradation is influenced more by the anhydride groups which are equal in number with the amide ones.
Zusammenfassung Das thermische Verhalten von Acrylamid-Maleinsäureanhydrid-Kopolymeren wurde durch thermogravimetrische Analyse (TG und DTG) untersucht. Aus den erhaltenen Daten wurden die Aktivierungsenergien und Reaktionsordnungen der Zersetzungsschritte nach den Methoden von Coats-Redfern und Freeman-Carroll berechnet. Durch thermische Analyse können im Falle von Polyacrylamid und AAMA (71 (-Kopolymeren 4 Peaks und bei AA:MA (11) -Kopolymeren nur 3 Peaks unterschieden werden. Bei AAMA (1 1)-Kopolymeren verläuft nur eine intermolekulare Imidisierung und der thermische Abbau wird mehr durch die in gleicher Zahl wie die Amidgruppen vorliegenden Anhydridgruppen beeinflußt.
T () — (). , - -, . : ( 71) , : 11 — . : 11 , , .相似文献
16.
Interaction of both satured and unsaturated hydrocarbons with tetrahedral Co2+ ion complexes lodged in the zeolite skeleton is reported on the basis of diffuse reflectance spectra. While saturated hydrocarbons do not affect the coordination sphere of the Co-complex, the unsaturated hydrocarbons change considerably the distortion of the tetrahedral Co-complex.
- Co2+ - . - Co-, - - Co-.相似文献
17.
Z. R. Ismagilov N. M. Dobrynkin V. V. Popovskii 《Reaction Kinetics and Catalysis Letters》1979,10(1):55-59
The oxidation of ethanol on CuO, CuO/Al2O3 and Pt/Al2O3 catalysts has been studied at various concentrations of alcohol, oxygen and water vapor in the reaction mixture. The reaction order and activation energies have been determined for both complete and partial oxidation processes. A consecutive oxidation scheme is suggested.
CuO, CuO/Al2O3 Pt/Al2O3 , . . .相似文献
18.
A. I. Yunusov N. D. Abdullaev Sh. Z. Kasymov G. P. Sidyakin M. R. Yagudaev 《Chemistry of Natural Compounds》1976,11(2):153-156
Summary From the leaves ofAtraphaxis pyrifolia Bge. we have isolated a new flavonoid glycoside. By chemical and spectroscopic investigations its structure has been established as 3,4,5,8-tetrahydroxy-7-methoxy-flavonol 3-O--L-rhamnopyranoside.S. M. Kirov Kazakh State University. Translated from Khimiya Prirodnykh Soedenenii, No. 2, pp. 136–140, March–April, 1975. 相似文献
19.
《Reaction Kinetics and Catalysis Letters》1982,20(1-2):99-105
, 1.2·1018/2 3.6·1018/2, . , .
The endothermic stage of desctruction of Al2O3 crystal lattice begins with the adsorption of a monolayer of chloride and hydrogen ions (1.2×1018 m–2 and 3.6×1018 m–2, respectively). The abrupt change in the Al content of the solution is attributed to the release of low-coordinate aluminium ions from the environment of the cationic vacancies of the oxide lattice.相似文献
20.
It has been found that when the reaction is carried out at pressures of the reaction mixture ranging from 1 to 400 Pa, small surface coverages by adsorbed oxygen, carbonate groups and irreversibly adsorbed carbon-containing particles are obtained. Rate relaxations are due to the concentration variations of adsorbed oxygen and CO3ads groups.
, 1–400 , , . CO3.相似文献