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191.
B. V. Pomorišac 《International Journal of Theoretical Physics》1984,23(6):575-583
We speculate on a generalized dynamics described by an integral over action functionals that is a generalization of the standard functional integral. In a simple Gaussian case we obtain a certain differential equation for the measure of Feynman integral. We prove that the equation is satisfied for the spin zero field in one space-time dimension. 相似文献
192.
Djordje Vlaović Gordana Ćetković Ivan Juranić Jelica Balaž Stevan Lajšić Dejan Djoković 《Monatshefte für Chemie / Chemical Monthly》1990,121(11):931-939
Summary The syntheses andin vitro antibacterial and antifungal evaluation of certain (5-nitro-2-furyl)azomethines with different heterocyclic nuclei are described.
Die Anwendung von Lävulinsäure und 5-Nitro-2-furylmethylendiacetat in der Totalsynthese einiger neuer biologisch aktiver (5-Nitro-2-furyl)azomethine
Zusammenfassung Es wird die Synthese und diein-vitro-antibakterielle und antifungale Wirksamkeit für bestimmte (5-Nitro-2-furyl)azomethine mit verschiedenen heterocyclischen Kernen beschrieben.相似文献
193.
Ulf Berg Marcia Berglund Nina Bladh Anette Svensson Magnus Stödeman 《Journal of inclusion phenomena and macrocyclic chemistry》1996,25(1-3):73-76
The properties of inclusion complexes of 1,4-di-R-bicyclo[2.2.2]octaves (R = H (1), Me (2), Cl (3), Br (4), and OH (5)) with cyclodextrins have been studied by NMR, microcalorimetry, and force-field computations. The compounds2 and3 (but not the other compounds) give dynamically stable 1:2 guest-host complexes with -cyclodextrin. Microcalorimetry of5 in water indicates a moderately strong 1:1 complex with - but weak complexes with - or -cyclodextrin. The behaviour depends on the subtle interplay size, polarity, hydrophobicity and type of solvent. 相似文献
194.
Štefan Marchalín Dušan Ilavský Milan Bruncko 《Monatshefte für Chemie / Chemical Monthly》1989,120(12):1101-1105
Summary Good yields of substituted 5-(5R-2-furyl)-4H-pyrano[2,3-d]pyrimidines4 were obtained in the reaction of 2-ethoxymethyleneamino-3-cyano-4H-pyranes2 with ammonia. Compounds2 were prepared by the condensation of the starting 2-amino-5-acetyl-3-cyano-6-methyl-4H-pyranes1 with ethyl orthoformate. Spectral properties of the bicyclic system4 in relation to compounds3 are discussed. 相似文献
195.
Summary The formation of V2O5 fibrous microcrystals in the V2O5-NH3-H2O system has been investigated by electron microscopy. The morphology of these microcrystals is dependent on the concentration of the particular components in the colloidal system and on the time of aging. In some colloid systems the orientation of V2O5 fibrous crystals with their long axes parallel to one another is also possible. The microcrystal growth in these systems can be attributed to very effective conditions for the recrystallization of vanadium pentoxide crystals in equilibrium with ammonium vanadate in solution.With 3 figures 相似文献
196.
Maleš Željan Plazibat Miško Vundać Vjera Bilušić Žuntar Irena Pilepić Kroata Hazier 《平面色谱法杂志一现代薄层色谱法》2004,17(4):280-285
JPC – Journal of Planar Chromatography – Modern TLC - The flowering tops of Hypericum hirsutum, H. montanum, H. perforatum subsp. angustifolium, H. perforatum subsp. perforatum, and H.... 相似文献
197.
The method is based on the oxidation of ethanol in the presence of alcohol oxidase, followed by oxidation of 2,2'-azino-di(3-ethylbenzthiazoline-6-sulfonate) in the presence of peroxidase. 相似文献
198.
199.
The present paper deals with the application of direct injection enthalpimetry (DIE) in the study of the kinetics of azo coupling reactions. On the example of the coupling of diazotized aniline-4-sulphonic acid with 1,8-dihydroxynaphthalene-3,6-disulphonic acid, it was verified that the rate constants determined using DIE are comparable with those determined using spectrophotometry. Advantages result from the application of DIE in the study of the kinetics of azo coupling reactions. 相似文献
200.
Then-component magnet with exchange anisotropy on a compressible lattice, with isotropic elastic properties, is studied. The renormalization group method is applied ind =4 — dimensions. The fixed points and the stability regions are explored to the order
2, and the analysis is concentrated upon the casen<4—2 +O(
2). Investigation of the fixed points reveals various crossover phenomena which are not present in the corresponding rigid model. Renormalization of the anisotropy crossover exponent is demonstrated. It is shown that macroscopic instabilities, leading to the first order phase transition, may appear. 相似文献