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31.
Enzo Martinelli 《Commentarii Mathematici Helvetici》1945,18(1):30-41
Ad Andreas Speiser nel suo 60o compleanno.
Anmerkung der Redaktion. Die vorliegende Arbeit war für die Festschrift Andreas Speiser, Orell Füssli, 1945, berechnet. Wegen versp?tetem Eintreffen
konnte sie leider nicht mehr in diese aufgenommen werden. 相似文献
32.
The components of Pygeum africanum bark extracts, used for the treatment of benign prostatic hypertrophy, were characterized by high resolution gas chromatography (HRGC) and mass spectrometry (MS). Among various compounds n-docosyl trans-ferulate was identified and quantitated by HRGC as a derivative of n-docosanol, which is considered to be one of the active components of the extract. The origin of different Pygeum a. extracts can be studied by eigenvector projection of HRGC profiles with computer assistance. 相似文献
33.
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
34.
Lees JP Poireau V Tisserand V Garra Tico J Grauges E Martinelli M Milanes DA Palano A Pappagallo M Eigen G Stugu B Brown DN Kerth LT Kolomensky YG Lynch G Koch H Schroeder T Asgeirsson DJ Hearty C Mattison TS McKenna JA So RY Khan A Blinov VE Buzykaev AR Druzhinin VP Golubev VB Kravchenko EA Onuchin AP Serednyakov SI Skovpen YI Solodov EP Todyshev KY Yushkov AN Bondioli M Kirkby D Lankford AJ Mandelkern M Stoker DP Atmacan H Gary JW Liu F Long O Vitug GM Campagnari C Hong TM Kovalskyi D 《Physical review letters》2011,107(22):221803
We search for hadronic decays of a light Higgs boson (A(0)) produced in radiative decays of an Υ(2S) or Υ(3S) meson, Υ→γA(0). The data have been recorded by the BABAR experiment at the Υ(3S) and Υ(2S) center-of-mass energies and include (121.3±1.2)×10(6) Υ(3S) and (98.3±0.9)×10(6) Υ(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions B(Υ(nS)→γA(0))B(A(0)→hadrons) (n=2 or 3) that range from 1×10(-6) for an A(0) mass of 0.3 GeV/c(2) to 8×10(-5) at 7 GeV/c(2). 相似文献
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37.
Corrado Di Natale Roberto Paolesse Eugenio Martinelli Rosamaria Capuano 《Analytica chimica acta》2014
The analysis of volatile compounds is an efficient method to appraise information about the chemical composition of liquids and solids. This principle is applied to several practical applications, such as food analysis where many important features (e.g. freshness) can be directly inferred from the analysis of volatile compounds. 相似文献
38.
39.
Pietro Caputo Fabio Martinelli François Simenhaus Fabio Lucio Toninelli 《纯数学与应用数学通讯》2011,64(6):778-831
We consider the Glauber dynamics for the Ising model with “+” boundary conditions, at zero temperature or at a temperature that goes to zero with the system size (hence the quotation marks in the title). In dimension d = 3 we prove that an initial domain of linear size L of “−” spins disappears within a time τ+, which is at most L2(log L)c and at least L2/(c log L) for some c > 0. The proof of the upper bound proceeds via comparison with an auxiliary dynamics which mimics the motion by mean curvature that is expected to describe, on large time scales, the evolution of the interface between “+” and “−” domains. The analysis of the auxiliary dynamics requires recent results on the fluctuations of the height function associated to dimmer coverings of the infinite honeycomb lattice. Our result, apart from the spurious logarithmic factors, is the first rigorous confirmation of the Lifshitz law τ+ ≃ const × L2, conjectured on heuristic grounds [8, 13]. In dimension d = 2, τ+ can be shown to be of order L2 without logarithmic corrections: the upper bound was proven in [6], and here we provide the lower bound. For d = 2, we also prove that the spectral gap of the generator behaves like for L large, as conjectured in [2]. © 2011 Wiley Periodicals, Inc. 相似文献
40.
D. Brunelli S. T. Levi P. Fragnoli A. Renzulli P. Santi E. Paganelli M. C. Martinelli 《Applied Physics A: Materials Science & Processing》2013,113(4):855-863
An integrated microchemical–petrographic approach is here proposed to discriminate the provenance of archaeological pottery artefacts from distinct production centres. Our study focuses on a statistically significant sampling (n=186) of volcanic temper-bearing potteries representative of the manufacturing and dispersion among the islands of the Aeolian Archipelago during the Bronze Age. The widespread establishment of new settlements and the abundant recovery of Aeolian-made ceramic in southern Italy attest for the increased vitality of the Archipelago during the Capo Graziano culture (Early Bronze Age–Middle Bronze Age 2; 2300–1430 BC). Potteries from three of the main known ancient communities (Lipari, Filicudi and Stromboli) have been studied integrating old collections and newly excavated material. Volcanic tempers have been first investigated through multivariate analyses of relative abundances of mineral and rock clasts along with petrographic characters. In addition, we performed in-situ mineral chemistry microanalyses by Electron Microprobe and Laser Ablation—Inductively Coupled Plasma Mass Spectrometry to assess major and trace element composition of the most common mineral phases. Four Temper Compositional Reference Units have been recognised based on compositional trends. Two units (AI and AX) are unequivocally distinct by their peculiar trace element enrichment and petrographic composition; they mostly contain samples from the sites of Lipari and Stromboli, respectively. Units AIV and AVIII, restricted to the sites of Filicudi and Stromboli, show distinct petrographic characters but overlapped geochemical fingerprints. 相似文献