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61.
Gradient bounds for minimizers of free discontinuity problems related to cohesive zone models in fracture mechanics 总被引:2,自引:0,他引:2
Gianni Dal Maso Adriana Garroni 《Calculus of Variations and Partial Differential Equations》2008,31(2):137-145
In this note we consider a free discontinuity problem for a scalar function, whose energy depends also on the size of the
jump. We prove that the gradient of every smooth local minimizer never exceeds a constant, determined only by the data of
the problem. 相似文献
62.
63.
64.
G. Dattoli B. Germano M.R. Martinelli P.E. Ricci 《Mathematical and Computer Modelling》2009,50(9-10):1332-1337
We show that the combination of the formalism underlying the principle of monomiality and of methods of an algebraic nature allows the solution of different families of partial differential equations. Here we use different realizations of the Heisenberg–Weyl algebra and show that a Sheffer type realization leads to the extension of the method to finite difference and integro-differential equations. 相似文献
65.
We use the Laguerre-type exponentials, i.e., eigenfunctions of the Laguerre-type derivatives, in order to construct new models for population growth. Relevant modifications of the classical exponential, logistic, and Volterra-Lotka models are investigated. 相似文献
66.
67.
We show that a standard hollow-core fiber (HCF) compressor device can be used to efficiently compress multi-mJ energy laser
pulses down to few-cycle duration, when seeded with linearly chirped, circularly polarized pulses. With this approach, we
routinely generate carrier-envelope phase (CEP)-locked, 1.6 mJ, 4.8 fs pulses using only 3 mJ, 25 fs pulses as the seed. 相似文献
68.
The dominant noises which limit the present sensitivity of the gravitational wave detectors are the thermal noise of the suspended
mirrors and the shot noise. For the third generation of gravitational wave detectors as the Einstein Telescope (ET), the reduction
of the shot noise implies to increase the power stored in the detector at 1 MW level and, at the same time, to compensate
the huge optic distortion due to induced thermal lensing. At low temperature it is possible to reduce both these effects.
However, lowering the temperature of the test masses without injecting vibration noise from the cooling system is a technological
challenge. We review here the thermal noise impact on the ultimate ET sensitivity limit and we discuss possible cryogenic
configurations to cool the mirror. 相似文献
69.
G. Ciasca M. Chiarpotto G. Campi B. Bocca M. Rodio A. Pino A. Ricci N. Poccia C. Rossi A. Alimonti H. Amenitsch P. De Sole A. Bianconi 《Journal of nanoparticle research》2011,13(11):6149-6155
This study investigates the uptake of iron and aluminium by apoferritin. In particular, we provide the first evidence that apoferritin is able to bind in vitro the physiological form of aluminium, Al(OH)4 ?, to reach an Al/Fe atomic ratio of about 0.15. Mass spectrometry analysis shows that the Al content increases linearly as a function of Al concentration in solution. These findings provide a better understanding of the Al uptake in vivo, confirming that the metal content of ferritin depends on the metal bio-availability. 相似文献
70.
Monica Dal Maso Isabel A. Perillo Celia B. Schapira Susana Gorzalczany María C. Acevedo Susana M. Sicardi 《Journal of heterocyclic chemistry》1999,36(3):803-811
A series of 4-hydroxy-2H-1,2-benzothiazme-3-carboxamide 1,1-dioxides substituted on the sulfonamide nitrogen with ethoxycarbonylalkyl, cyanoalkyl and dialkylaminoalkyl groups was synthesized. Spectroscopic properties of the obtained products were analyzed. Findings from the pharmacological study of some of the compounds as antiinflammatory and analgesic agents are reported. 相似文献