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781.
Marcelle de Lima Ferreira Bispo Raoni Schroeder Borges Gonçalves Camilo Henrique da Silva Lima Laura Nogueira de Faria Cardoso Maria Cristina Silva Lourenço Marcus Vinícius Nora de Souza 《Journal of heterocyclic chemistry》2012,49(6):1317-1322
Two series of pyrazinamide (PZA) derivatives have been synthesized and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis H37Rv. Some compounds exhibited minimum inhibitory concentration activity of 50–100 μg/mL, greater than the first line antituberculosis drug PZA in Alamar Blue assay (>100 μg/mL). The obtained activities can be considered promising results, which characterizes these compounds as good start points to development of new antitubercular agents. 相似文献
782.
We predict the formation of optically trapped, metal-dielectric nanoparticle clusters above photonic crystal microcavities. We determine the conditions on particle size and position for a gold particle to be trapped above the microcavity. We then show that strong field redistribution and enhancement near the trapped gold nanoparticle results in secondary trapping sites for a pair of dielectric nanoparticles. 相似文献
783.
Gabriel Navarro 《Advances in Mathematics》2010,224(3):1121-1142
A classical theorem of John Thompson on character degrees states that if the degree of any complex irreducible character of a finite group G is 1 or divisible by a prime p, then G has a normal p-complement. In this paper, we consider fields of values of characters and prove some improvements of this result. 相似文献
784.
Let be a random vector, and denote by X1:n,X2:n,…,Xn:n the corresponding order statistics. When X1,X2,…,Xn represent the lifetimes of n components in a system, the order statistic Xn−k+1:n represents the lifetime of a k-out-of-n system (i.e., a system which works when at least k components work). In this paper, we obtain some expressions for the Pearson’s correlation coefficient between Xi:n and Xj:n. We pay special attention to the case n=2, that is, to measure the dependence between the first and second failure in a two-component parallel system. We also obtain the Spearman’s rho and Kendall’s tau coefficients when the variables X1,X2,…,Xn are independent and identically distributed or when they jointly have an exchangeable distribution. 相似文献
785.
786.
A.Camilo P. Alves J.Michael Hollas Hamdan Musa Trevor Ridley 《Journal of Molecular Spectroscopy》1985,109(1):99-122
Single vibronic level fluorescence (SVLF) spectra of tropolone from vibronic levels in the electronic state, in combination with recently reported supersonic jet spectra, have enabled the assigning of many absorption bands in the region of 000 which had previously been impossible. Some of the complexity in these bands has been shown to be due to a large Duschinsky effect involving the two lowest b1 vibrations, ν25 and ν26. It has been shown that these vibrations have wavenumbers of 176 and 110 cm?1, respectively, in the state, and 172 and 39 cm?1 in the state. This last value shows how unresistent the molecule is in the state to out-of-plane bending in the region of the five-membered ring. Other aspects of the vibrational complexity are due to the effect of ν′26 in increasing the barrier to tunnelling of the hydrogen-bonding proton in the state contrasting with very little effect of ν″26 in the state. 相似文献
787.
Sergio R. Canoy Milagros P. Navarro 《Rendiconti del Circolo Matematico di Palermo》1995,44(2):330-336
In this paper, we shall show that theHL ϕ-integral and the Denjoy ϕ-integral, defined in [2] are equivalent. 相似文献
788.
789.
C. B. Navarro R. Quintanilla 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1984,35(2):206-215
Summary Existence and uniqueness of solutions to the evolution equations which govern small thermoelastic deformations superposed on a general non-linear thermomechanical deformation is investigated. The problem is solved by means of the semigroup theory applied to the abstract temporally inhomogeneous equation arising in this case.
Résumé On étudie l'existence et l'unicité des solutions des équations qui gouvernent les petites déformations thermoélastiques superposés à un procés thermomécanique non linéaire général. Le problème est résolu à l'aide de la théorie des semigroupes apliquée à l'équation abstraite non homogène.相似文献
790.