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51.
We discuss local solvability of operators of the form
where theV
j
are left-invariant vector fields on the Heisenberg group such that [V
j
,V
j+n
]=U for 1≤j≤n andA=(a
jk
)=A
1+iA
2 is a complex symmetric matrix satisfying the “cone condition” |A
2|≤CA
1.
The authors acknowledge the support for this work by the European Commission through the European HCM-program “Fourier Analysis”
and the TMR network “Harmonic Analysis”. 相似文献
52.
Given a real polynomial in one variable such that , we consider the maximal operator in ,
We prove that is bounded on for 1$"> with bounds that only depend on the degree of .
0\,,\,i,j\in \mathbb{Z}}\frac{1... ...t f\big (x_{1}-2^{i}p(t),x_{2}-2^{j}p(t)\big )\big \vert\,dt . \end{displaymath}">
We prove that is bounded on for 1$"> with bounds that only depend on the degree of .
53.
A nonlinear model associated to the motion of a membrane is considered as limit of a sequence of approximate models, for which a global existence and uniqueness theorem can be proved. The paper investigates the relationship between the solutions of the real and approximate models. 相似文献
54.
A symbolic algorithm based on the generalized Lucas polynomials of first kind is used in order to compute the Newton sum rules for the zeros of polynomial eigenfunctions of linear differential operators with polynomial coefficients. 相似文献
55.
Fulvio Ricci Giancarlo Travaglini 《Proceedings of the American Mathematical Society》2001,129(6):1739-1744
Let be a convex curve in the plane and let be the arc-length measure of Let us rotate by an angle and let be the corresponding measure. Let . Then This is optimal for an arbitrary . Depending on the curvature of , this estimate can be improved by introducing mixed-norm estimates of the form where and are conjugate exponents. 相似文献
56.
57.
G. Viesti B. Fornal F. Gramegna G. Prete R. A. Ricci G. D'Erasmo L. Fiore G. Guarino A. Pantaleo I. Iori A. Moroni P. Blasi F. Lucarelli 《Zeitschrift für Physik A Hadrons and Nuclei》1986,324(2):161-171
The reactions induced by 143 MeV32S on58Ni have been studied detecting discrete γ-rays in coincidence with projectile-like fragments (PLF). Information on PLF excitation probability and sequential decay of target-like fragments (TLF) has been obtained. For the28Si+62Zn outgoing channel at small energy loss (¦Q¦<20 MeV), both PLF and TLF data indicate that thermal equilibrium is not attained. The hypothesis of an equal excitation energy partition between the two reaction fragments does not describe properly experimental TLF data. A dependence of PLF excitation probability on the outgoing channel is found for the two final channels32S+58Ni and28Si+62Zn. The values of the spin alignment parameterP zz, derived for PLF and TLF from measurements ofγ-rays anisotropy, are in disagreement with the expectations of the transport theory for dissipative collisions. 相似文献
58.
C. Rossi C. Bonechi S. Martini M. Ricci G. Corbini P. Corti A. Donati 《Magnetic resonance in chemistry : MRC》2001,39(8):457-462
Proton NMR selective and non-selective spin–lattice relaxation rate measurements were used to monitor the strength of the overall complexation behaviour of a ligand (carbamazepine) toward a macromolecular receptor (albumin). The ‘affinity index,’ a quantitative parameter related to the strength of the ligand–macromolecule interaction, was determined from the experimental contribution of the bound ligand molar fraction to the observed selective spin–lattice relaxation rate. The effect of a second ligand (lamotrigine) on the carbamazepine–albumin interaction was also investigated and was found to have a modulation effect on the carbamazepine–albumin interaction. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
59.
60.
Sparzak Barbara Krauze-Baranowska Mirosława Pobłocka-Olech Loretta 《平面色谱法杂志一现代薄层色谱法》2008,21(2):103-106
JPC – Journal of Planar Chromatography – Modern TLC - Densitometric HPTLC has been used for determination of catechins in shoot and callus cultures of two species from the genus... 相似文献