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31.
A simple model for the numerical determination of separation effects in seeded atomic gas flows is presented. The model is based on the known possibility to provide a statistically convergent estimate of the exact solution for a linear transport equation using the test particle Monte Carlo method. Accordingly, the flow field of the main gas is preliminary calculated and as a second step the linear transport equations obtained by fixing the target distribution in the collision term of the Boltzmann equation for both main and minority components are solved. Both solutions are based on appropriately devised test particle Monte Carlo methods. The second step, the critical one in evaluating the separation effects, is exact and thereby completely free of numerical diffusion. The model is described in details and illustrated by 2D test cases of atomic separation in shock fronts. 相似文献
32.
33.
Edoardo Longo Ksenia Morozova Sine Yener Emanuele Boselli Franco Biasioli Matteo Scampicchio 《Journal of mass spectrometry : JMS》2019,54(5):412-421
This work proposes a novel method for the direct flow injection profiling of acylglycerols in edible oils and fats without preliminary extraction and consequent reconstitution in the injection solvent. The work exploits the outstanding performance of high‐resolution mass spectrometry to target unique elemental compositions even in the most complex matrices. The performance of isopropanol as the unique solvent for both the solubilization and analysis of acylglycerols was investigated in comparison with other classical methods involving preliminary extractions, sample recovery, and analysis. The calibrations of two triglyceride standards (triolein and trilinolenin) were successfully performed in presence and absence of oil matrix. As final application, the effects on the acylglycerol fraction of a heat treatment on three different fat samples (extra virgin olive oil, lard oil, and fat from dry cured ham—speck) were monitored. The proposed method is therefore suitable for a rapid evaluation of acylglycerol fractions in food lipid samples. 相似文献
34.
We build up local, time translation covariant Boundary Quantum Field Theory nets of von Neumann algebras ${\mathcal A_V}$ on the Minkowski half-plane M + starting with a local conformal net ${\mathcal A}$ of von Neumann algebras on ${\mathbb R}$ and an element V of a unitary semigroup ${\mathcal E(\mathcal A)}$ associated with ${\mathcal A}$ . The case V?=?1 reduces to the net ${\mathcal A_+}$ considered by Rehren and one of the authors; if the vacuum character of ${\mathcal A}$ is summable, ${\mathcal A_V}$ is locally isomorphic to ${\mathcal A_+}$ . We discuss the structure of the semigroup ${\mathcal E(\mathcal A)}$ . By using a one-particle version of Borchers theorem and standard subspace analysis, we provide an abstract analog of the Beurling-Lax theorem that allows us to describe, in particular, all unitaries on the one-particle Hilbert space whose second quantization promotion belongs to ${\mathcal E(\mathcal A^{(0)})}$ with ${\mathcal A^{(0)}}$ the U(1)-current net. Each such unitary is attached to a scattering function or, more generally, to a symmetric inner function. We then obtain families of models via any Buchholz-Mack-Todorov extension of ${\mathcal A^{(0)}}$ . A further family of models comes from the Ising model. 相似文献
35.
M. Convery W. L. Davis K. DelSignore T. L. Jenkins E. Kangas M. Knepley K. L. Kowalski C. C. Taylor C. H. Wang S. H. Oh W. D. Walker P. L. Colestock B. Hanna M. A. Martens J. M. Streets R. C. Ball H. R. Gustafson L. W. Jones M. J. Longo J. D. Bjorken N. Morgan C. Pruneau 《Il Nuovo Cimento C》1996,19(6):1045-1049
Summary A small experiment, ?MiniMax?, has been set up in the C0 intersection region of the Fermilab Tevatron to seek evidence for
disoriented chiral condensates and to study other forward physics phenomena. The experiment consists of a proportional wire
chamber telescope accompanied by scintillation (trigger) counters, a lead converter, and followed by an electromagnetic calorimeter.
The solid angle accepted is a cone centered at pseudorapidity (η) of 4.1 and of radius (in η-ϕ space) of about 0.6. Over 2.5
million events thus far have demonstrated the successful operation of the apparatus, however to date the analysis has not
progressed sufficiently to permit any conclusions concerning disoriented chiral condensates.
presented byL. W. Jones
Paper presented at the Special Session on very high-energy cosmic-ray interactions (superfamilies) of the XXIV International
Cosmic-Ray Conference, Rome, August 28–September 8, 1995. 相似文献
36.
Carmelo Longo 《Annali di Matematica Pura ed Applicata》1962,60(1):249-264
Sunto Per gli E2 di un piano e di dato centro e per gli E3 di un piano per un dato E1 è data una rappresentazione analitica mediante parametri omogenei la quale permette un'interpretazione dei punti di chiusura
della varietà rappresentativa degli elementi regolari mediante elementi non regolari diversa da quelle finora considerate.
A Enrico Bompiani in occasione del suo giubileo scientifico 相似文献
37.
Michael J. Longo 《Nuclear Physics B》1978,134(1):70-82
It is shown that all aspects of the data on inclusive single-particle production from nuclei can be understood in terms of a model in which the interaction with the nucleus occurs through one or more elastic q-q scatterings. Successive scatters areassumeed to be mostly incoherent. No cascading occurs because “dressing” of the scattered quarks does not take place until after the quarks leave the nucleus. 相似文献
38.
M. I. B. Bernardi E. R. Leite E. Longo M. M. Conceiçăo A. G. Souza 《Journal of Thermal Analysis and Calorimetry》2004,75(2):481-486
The color efficiency of ceramic glaze blue pigments obtained by the Pechini method was presented in this work. The fired pigments
and enameled samples were characterized by thermogravimetry (TG) and differential thermal analysis (DTA), XRD, UV-VIS-NIR
spectroscopy and CIE-L*a*b* color-measurements. The pigments obtained by the Pechini method present a better solubility in
the molten glazes than the pigments obtained by the mechanical mixture of the precursor oxides.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
39.
Luk KB Diehl HT Duryea J Guglielmo G Heller K Ho PM James C Johns K Longo MJ Rameika R Teige S Thomson GB Zou Y 《Physical review letters》2000,85(23):4860-4863
A search for direct CP violation in the nonleptonic decays of hyperons has been performed. In comparing the product of the decay parameters, alpha(Xi)alpha(Lambda), in terms of an asymmetry parameter, A(XiLambda), between hyperons and antihyperons in the charged Xi-->Lambdapi and Lambda-->ppi decay sequence, we found no evidence of direct CP violation. The parameter A(XiLambda) was measured to be 0.012+/-0.014. 相似文献
40.
Carmen Bocchino Mariagrazia Napoli Chiara Costabile Pasquale Longo 《Journal of polymer science. Part A, Polymer chemistry》2011,49(4):862-870
The synthesis and characterization of a zirconium complex, having two alkoxide functionalized N‐heterocyclic carbene ligands, and its behavior as catalyst in the polymerization of ethylene and propylene, have been reported. NMR analysis showed that more than one species was obtained during synthesis. These data were confirmed by ethylene polymerization that gave rise to a linear polyethylene having a high Molecular weight and a polydispersity index (MDI) > 2 and often bimodal. The same catalytic system was able to produce highly isotactic polypropylene together with an atactic fraction. DFT studies on the complex stereoisomer stability gave indications on the species possibly involved in the polymerizations. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献