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71.
Jean Dolbeault Maria J. Esteban Javier Duoandikoetxea Luis Vega 《Annales Scientifiques de l'école Normale Supérieure》2007,40(6):885-900
We prove some Hardy type inequalities related to the Dirac operator by elementary methods, for a large class of potentials, which even includes measure valued potentials. Optimality is achieved by the Coulomb potential. When potentials are smooth enough, our estimates provide some spectral information on the operator. 相似文献
72.
Maria J Esteban 《Journal of Differential Equations》1985,57(1):112-137
In this paper lower bounds for the number of solutions of semilinear elliptic problems in a ball of N are given. Its hypotheses are only related to the behavior of the nonlinearities at ±∞ and at 0. Global assumptions are never made. For example, oddness is never required for the proof of multiplicity results. 相似文献
73.
Javier Gamboa Félix Javier Jiménez-Jiménez Alberto Nieto Ignacio Cobeta Alberto Vegas Miguel Ortí-Pareja Teresa Gasalla José Antonio Molina Esteban García-Albea 《Journal of voice》1998,12(4):444-452
To quantify several acoustic features of the voice in patients with essentialtremor (ET), 28 patients and 28 age- and sex-matched controls were studied. ET severity was assessed with the rating scale for tremor of Fahn, Tolosa, and Marín. The Computerized Speech Lab 4300 program (Kay Elemetrics) was used. Two-second samples of a sustained /a/ and a sentence were captured with a microphone and laryngograph equipment. Measures included fundamental frequency (F0), frequency perturbation (fitter, Koike algorithm), intensity perturbation (shimmer, Horii algorithm), and harmonic-to-noise ratio (H/N, Yumoto algorithm) of the vowel /a/, and the frequency and intensity variability of the sentence, phonational range, and dynamic range at the natural frequency, maximum phonational time, and s/z ratio. All subjects underwent indirect laryngoscopy and/or laryngeal fibroscopy. When compared with controls, ET patients showed higher jitter, lower H/N ratio (the last one only with laryngographic signal), of the vowel /a/, lower frequency variability in the microphonc signal, lower intensity variability in the laryngographic signal of the sentence, and significantly lower dynamic range at natural frequency of phonation. ET patients reported higher frequency of the presence of high voice intensity, tremor, and struggle. Several acoustic parameters were influenced by the severity of the disease, including shimmer, jitter, H/N ratio, frequency variability of the sentence, and s/z ratio, although neither of the acoustic analysis values or the phonetometric measurements were affected by the presence of voice tremor or by a successful pharmacological treatment of ET. 相似文献
74.
75.
The synthesis and properties of rhodium(I) complexes of formulae [“RhCl(diolefin)”2(L)] (or [Rh(Cl(diolefin)(L)]), and [Rh(diolefin)(L)]n(ClO4)n are reported. These complexes react with carbon monoxide to yield the related carbonyl derivatives. Ligands used were pyridazine, 4,6-dimethyl-pyrimidine, 4,6-bis(3,5-dimethylpyrazol-1-yl)pyrimidine, 3,6-bis(3,5-dimethylpyrazol-1-yl)pyridazine and 3-(3,5-dimethyl-pyrazol-1-yl)-6-chloropyridazine. Related iridium(I) and gold(I) compounds are also reported. 相似文献
76.
77.
S. Agosteo G.A.P. Cirrone P. Colautti G. Cuttone G. D’Angelo A. Fazzi M.V. Introini D. Moro A. Pola V. Varoli 《Radiation measurements》2010,45(10):1284-1289
A monolithic silicon device consisting of a matrix of micrometric cylindrical diodes (about 2 μm in thickness and 9 μm in diameter) coupled to a residual energy measurement stage E (about 500 μm in thickness) was proposed and studied for assessing the quality of a therapeutic proton beam. The device was placed at different depths inside a polymethyl-methacrylate phantom and irradiated with a modulated 62 MeV proton beam at the Centro di AdroTerapia e Applicazioni Nucleari Avanzate (CATANA) of the Laboratori Nazionali del Sud (LNS, Catania, Italy) of the Istituto Nazionale di Fisica Nucleare (INFN).At each phantom depth, the energy imparted in the two detector stages was measured event-by-event in coincidence mode. The distributions of the energy imparted to the cylindrical diodes were corrected for tissue-equivalence by applying an optimized procedure. In order to perform a comparison with literature data measured with a cylindrical TEPC, the distributions derived with the silicon detector were corrected for shape-equivalence. The agreement with the microdosimetric spectra measured with the TEPC was satisfactory above the detection limit imposed by the electronic noise of the silicon-based system. 相似文献
78.
V. Conte L. De Nardo P. Colautti A. Ferretti B. Grosswendt M. Lombardi M. Poggi S. Canella D. Moro G. Tornielli 《Radiation measurements》2010,45(10):1213-1216
The STARTRACK experimental set-up, mounted on the +50° beam line of the Tandem-Alpi particle accelerator of Legnaro National Laboratories, has been conceived to give an experimental basis to nanodosimetric calculations. STARTRACK is based on a detection system able to measure ionization cluster distributions in a 20 nm propane site with a resolution of one ionization. The experimental layout has been designed to minimize pile-up distortions. The background noise is filtered by off-line dedicated software. Electron cluster distribution of 20 MeV protons has been measured. Monte Carlo data and experimental data are pretty well consistent. 相似文献
79.
E. Vardaci A. Di Nitto A. Brondi G. La Rana R. Moro P. N. Nadotchy M. Trotta A. Ordine A. Boiano M. Cinausero E. Fioretto G. Prete V. Rizzi D. Shetty M. Barbui D. Fabris M. Lunardon G. Montagnoli S. Moretto G. Viesti N. Gelli F. Lucarelli G. N. Knyazheva E. M. Kozulin 《The European Physical Journal A - Hadrons and Nuclei》2010,43(2):127-130
80.
Petru Jebelean Gheorghe Moro?anu 《Journal of Mathematical Analysis and Applications》2006,313(2):738-753
This paper is concerned with the existence of solutions for the boundary value problem