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51.
A convenient route to new 3-quinolinonyl-pyrazoles and isoxazoles is described through cyclization of 3-[(E)-3-(dimethylamino)-2-propenoyl]-4-hydroxy-1-methyl-2(1H)-quinolinone. The phototoxicity as well as the cytotoxic activities of the title compounds are evaluated against leukemia- and adenocarcinoma-derived cell lines in comparison to the normal human keratinocytes. 相似文献
52.
Giovannelli Tommaso Liuzzi Giampaolo Lucidi Stefano Rinaldi Francesco 《Computational Optimization and Applications》2022,82(2):293-327
Computational Optimization and Applications - In this paper, mixed-integer nonsmooth constrained optimization problems are considered, where objective/constraint functions are available only as the... 相似文献
53.
Mirko Degli Esposti Sandro Graffi Stefano Isola 《Communications in Mathematical Physics》1995,167(3):471-507
The canonical quantization of any hyperbolic symplectomorphismA of the 2-torus yields a periodic unitary operator on aN-dimenional Hilbert space,N=1/h. We prove that this quantum system becomes ergodic and mixing at the classical limit (N,N prime) which can be interchanged with the time-average limit. The recovery of the stochastic behaviour out of a periodic one is based on the same mechanism under which the uniform distribution of the classical periodic orbits reproduces the Lebesgue measure: the Wigner functions of the eigenstates, supported on the classical periodic orbits, are indeed proved to become uniformly speread in phase space. 相似文献
54.
Behzad, Chartrand and Wall proposed the conjecture that any regular digraph of degreer and girthg has ordern r(g – 1) + 1. The conjecture was proved in [3] for vertex transitive graphs. For Loop Networks the conjecture is equivalent to a theorem of Shepherdson in additive number theory. We show that, except for graphs of a particular structure, Loop Networks, and in general Abelian Cayley graphs, verify the stronger inequalityn (r + 1)(g – 1) – 1. This bound is best possible.Supported by the Spanish Research Council (CICYT) under project TIC 90-0712 and Acción Integrada Hispanofrancesa, TIC 79B. 相似文献
55.
It is studied the convergence of solutions of Dirichlet problems for sequences of monotone operators of the type — div (ah (x, D·)), where the functions ah verify the following degenerate coerciveness assumption
相似文献
56.
57.
Stefano Capparelli 《Transactions of the American Mathematical Society》1996,348(2):481-501
We obtain a vertex operator construction of level 3 standard representations for the affine Lie algebra . As a corollary, we also get new conbinatorial identities.
58.
Stefano Serra 《BIT Numerical Mathematics》1996,36(1):135-142
In this paper we are concerned with the asymptotic behavior of the smallest eigenvalue
1
(n)
of symmetric (Hermitian)n ×n Toeplitz matricesT
n
(f) generated by an integrable functionf defined in [–, ]. In [7, 8, 11] it is shown that
1
(n)
tends to essinff =m
f
in the following way:
1
(n)
–m
f
1/n
2k
. These authors use three assumptions:A1)f –m
f
has a zero inx =x
0 of order 2k.A2)f is continuous and at leastC
2k
in a neighborhood ofx
0.A3)x =x
0 is the unique global minimum off in [–, ]. In [10] we have proved that the hypothesis of smoothnessA2 is not necessary and that the same result holds under the weaker assumption thatf L
1[–, ]. In this paper we further extend this theory to the case of a functionf L
1[–, ] having several global minima by suppressing the hypothesisA3 and by showing that the maximal order 2k of the zeros off –m
f
is the only parameter which characterizes the rate of convergence of
1
(n)
tom
f
. 相似文献
59.
Some results on configurations realizing minimum blocking sets of a finite projective plane are obtained by introducing a suitable attraction property.Dedicated to Professor M. Scafati Tallini on the occasion of her 65th birthday 相似文献
60.
The complex formation between pyrophosphate (P(2)O(7)(4-)) and protonated methylamine, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine and pentaethylenehexamine, has been studied potentiometrically, in aqueous solution, at 25 degrees C. It was found that the species ALH(q)(A = amine, L = P(2)O(7)(4-)) are formed with q = 1 ... n(n = 3, 5, 6, 7, 7 and 8 for the above amines respectively). Mono- and di-amines form species A(p)LH(q) too. The stability of these species is quite high [e.g. H(4)A(4+) + HL(3-)ALH(5)(+): log K = 8.1 (A = pentaethylenehexamine)] and depends strictly on the charges involved in the formation reaction. Charges of reactants being equal, the stability trend is penten > tetren > trien > dien > en > meta and cationic mixed species are more stable than anionic ones. These results are discussed in relation to speciation problems in natural and biological fluids. 相似文献
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