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781.
A. Paul Krapcho Cynthia E. Gallagher Abdelhakim Hammach Miles P. Hacker Ernesto Menta Ambrogio Oliva Roberto Di Domenico Giovanni Da Re Andrea Lotto Silvano Spinelli 《Journal of heterocyclic chemistry》1998,35(4):895-906
Synthetic routes have been developed which lead to ring-hydroxylated aza-analogues of antitumor anthrapyrazoles, namely, 2,5-bis[(aminoalkyI)amino] substituted 10-hydroxymdazolo[3,4-fg]isoquinolin-6(2H)-ones 1 and 7-hydroxyindazolo[4,3-gh]isoquinolin-6(2H)-ones 2 . The regiospecific synthesis of 6,9-dihalo-4-hydroxybenz[g]isoquinolines 3 and 4 has been accomplished. Intermediate 3 was constructed in a multistep process involving Diels-Alder chemistry of benzoylacrylates whereas 4 was assembled using Ni(II) mediated coupling of methyl 3-chloro-5-methoxyisonicotinate ( 15b ) with the organic zinc reagent 18 derived from 2-fluoro-5-chlorobenzyl bromide ( 17 ). After protection of the hydroxy group with a p-methoxybenzyl moiety, the different nucleofugacities of the leaving groups present in 10 and 20 allowed sequential displacements by substituted hydrazines and amines, respectively, to lead to the desired p-methoxybenzyl protected analogues 12 and 22 . Deprotection led to the side arm modified compounds 1 and 2 . The displacements of 21a and 21b with N,N-dimethylethylenediamine also led to the tri[(aminoalkyl)amino]substituted analogues 23a and 23b , respectively, which arose from further SNAr substitutions of the p-methoxybenzyloxy group. 相似文献
782.
In this paper we characterize a class of finite planar spaces whose planes have two sizes.Dedicato alla memoria dell'amico e Maestro Giuseppe TalliniWork supported by G.N.S.A.G.A. of C.N.R. and the projects M.U.R.S.T. 40 % 相似文献
783.
Summary We prove that graphs of continuous maps with finite area can be approximated weakly as currents and in area by graphs of smooth maps.This article was processed by the author using the style filepljour1m from Springer-Verlag. 相似文献
784.
Pier Domenico Lamberti 《Applied Mathematics and Optimization》2009,59(3):319-327
We study the dependence of the eigenvalues of a N-dimensional vibrating membrane upon variation of the mass density. We prove that the elementary symmetric functions of the
eigenvalues depend real-analytically on the mass density and that such functions have no critical points with constant mass
constraint. In particular, the elementary symmetric functions of the eigenvalues, hence all simple eigenvalues, have no local
maxima or minima on the set of those mass densities with a prescribed total mass. 相似文献
785.
Domenico Fusco Natale Manganaro 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2008,46(8):63-75
A reduction approach is developed in order to construct generalized simple wave solutions to quasilinear nonhomogenous hyperbolic
systems of first order PDEs. The solutions sought must possess a special ansatz which permits time-evolution of the profile
of a simple wave due to a source-like term. These solutions involve a free function which can be used to fit classes of initial
or boundary value problems. By means of the proposed approach two governing models of interest in a variety of applications
are investigated. Model constitutive laws consistent with the full reduction process are obtained and the occurence of singularities
at a finite time for the resulting solutions is analysed. Furthermore a comparison is made between the results obtained within
the present theoretical framework and the standard simple wave solutions of the corresponding homogeneous (source free) governing
models. 相似文献
786.
Ohne Zusammenfassung 相似文献
787.
In this paper a characterization of PG(r, q), r ≥ 4, in terms of planar spaces is given.
Domenico Olanda: This research was carried out within the activity of INdAM-GNSAGA and supported by the Italian Ministry M.I.U.R. 相似文献
788.
789.
We show that, for pertinent values of the fabrication and control parameters, an attractive finite coupling fixed point emerges in the phase diagram of a Y-junction of superconducting Josephson chains. The new fixed point arises only when the dimensionless flux f piercing the central loop of the network equals π and, thus, does not break time-reversal invariance; for f≠π, only the strongly coupled fixed point survives as a stable attractive fixed point. Phase slips (instantons) have a crucial role in establishing this transition: we show indeed that, at f=π, a new set of instantons—the W-instantons—comes into play to destabilize the strongly coupled fixed point. Finally, we provide a detailed account of the Josephson current–phase relationship along the arms of the network, near each one of the allowed fixed points. Our results evidence remarkable similarities between the phase diagram accessible to a Y-junction of superconducting Josephson chains and the one found in the analysis of quantum Brownian motion on frustrated planar lattices. 相似文献
790.
A large sample study of spin relaxation and magnetometric sensitivity of paraffin-coated Cs vapor cells 总被引:1,自引:0,他引:1
N. Castagna G. Bison G. Di Domenico A. Hofer P. Knowles C. Macchione H. Saudan A. Weis 《Applied physics. B, Lasers and optics》2009,96(4):763-772
We have manufactured more than 250 nominally identical paraffin-coated Cs vapor cells (28 mm inner diameter bulbs) for multi-channel
atomic magnetometer applications. We describe our dedicated cell characterization apparatus. For each cell we have determined
the intrinsic longitudinal, Γ
01, and transverse, Γ
02, relaxation rates. Our best cell shows Γ
01/2π≈0.5 Hz, and Γ
02/2π≈2 Hz. We find a strong correlation of both relaxation rates which we explain in terms of reservoir and spin exchange relaxation.
For each cell we have determined the optimal combination of rf and laser powers which yield the highest sensitivity to magnetic
field changes. Out of all produced cells, 90% are found to have magnetometric sensitivities in the range of 9 to 30 fT
. Noise analysis shows that the magnetometers operated with such cells have a sensitivity close to the fundamental photon
shot noise limit. 相似文献