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31.
S. A. Koldobskiy O. Adriani G. A. Bazilevskaya G. C. Barbarino R. Bellotti E. A. Bogomolov M. Boezio V. Bonvicini M. Bongi S. Bottai A. Bruno A. Vacchi E. Vannuccini G. I. Vasilyev S. A. Voronov A. M. Galper C. De Santis V. Di Felice G. Zampa N. Zampa M. Casolino D. Campana A. V. Karelin P. Carlson G. Castellini F. Cafagna A. A. Kvashnin A. N. Kvashnin S. V. Koldashov S. Y. Krutkov A. A. Leonov A. G. Mayorov V. V. Malakhov M. Martucci L. Marcelli W. Menn M. Merge V. V. Mikhailov E. Mocchiutti A. Monaco N. Mori R. Munini G. Osteria B. Panico P. Papini P. Picozza M. Pearce M. Ricci S. B. Ricciarini M. F. Runtso M. Simon R. Sparvoli P. Spillantini Y. I. Stozhkov Y. T. Yurkin 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(2):151-153
The preliminary results from measurements of deuteron fluxes in galactic cosmic rays (GCR) in the vicinity of the Earth in 2006–2009 are presented. The results are obtained by analyzing data from the PAMELA experiment aboard the Resurs DK-1 satellite. High-precision detection instruments provided an opportunity to identify GCR deuterons and measure their spectrum in the energy interval of 90–650MeV/nucleon. Spectra averaged over six-month intervals from the summer of 2006 to the summer of 2009 (the solar activity minimum) are presented. The influence of solar modulation on the observed spectrum is clearly seen in the results. 相似文献
32.
Summary A plane semidiscrete model of the Boltzmann equation for a binary gas mixture with molecular collisions ruled by the hard-spheres interaction potential is described. After establishing a model, a theorem demostrating the global existence of mild solutions of the initial-value problem is given and the propagation of unidimensional shock waves examined.
Sommario Si propone un modello semidiscreto piano dell'equazione di Boltzmann per una miscela binaria con collisioni molecolari soggette al potenziale di interazione delle sfere rigide. Costruito il modello, si dà un teorema di esistenza globale di soluzioni generalizzate per il problema di Cauchy, e si analizza la propagazione di onde d'urto unidimensionali.相似文献
33.
Laura Zanetti-Polzi Paolo Marracino Massimiliano Aschi Isabella Daidone Antonella Fontana Francesca Apollonio Micaela Liberti Guglielmo D’Inzeo Andrea Amadei 《Theoretical chemistry accounts》2013,132(11):1-10
A benchmark biochemical reaction is here theoretically investigated by means of a perturbative approach in order to model each reaction step. The reaction is the flavin-indole electron transfer, involving also a spin-state relaxation of the ionic complex. The whole reaction path is modeled and the kinetics of the process is studied. The dipolar interaction between the two radicals is explicitly considered during the dynamic evolution of the system in order to investigate the proper conditions for the triplet-to-singlet transition to occur. 相似文献
34.
Guglielmo Monaco 《Journal of mathematical chemistry》2011,49(8):1544-1557
A novel exact derivation for the kinetic constant of a bimolecular reaction according to three well-known models of collision
theory is reported. The use of probability density functions, with the introduction of a novel geometry to study the collision
process, allows simplifying the derivation to such an extent, that, for a proper statistical background, it is is possible
to recover the line-of-centers and the angular dependent line-of-centers models in no more than a couple of lectures. Although
the derivation is introduced to recover the temperature-dependent kinetic constant, it is shown that the energy-dependent
reactive cross section can be recovered as well. A possible confusion in the interpretation of the pre-exponential factor
is commented. 相似文献
35.
36.
Guglielmo Lunardon 《Journal of Combinatorial Theory, Series A》2006,113(6):1172-1188
We find a relationship between semifield spreads of PG(3,q), small Rédei minimal blocking sets of PG(2,q2), disjoint from a Baer subline of a Rédei line, and translation ovoids of the hermitian surface H(3,q2). 相似文献
37.
Dr. Alessandra Alberti Dr. Ioannis Deretzis Dr. Giovanna Pellegrino Dr. Corrado Bongiorno Dr. Emanuele Smecca Dr. Giovanni Mannino Dr. Filippo Giannazzo Prof. Guglielmo Guido Condorelli Dr. Nobuya Sakai Prof. Tsutomu Miyasaka Dr. Corrado Spinella Dr. Antonino La Magna 《Chemphyschem》2015,16(14):3064-3071
We investigate the degradation path of MAPbI3 (MA=methylammonium) films over flat TiO2 substrates at room temperature by means of X‐ray diffraction, spectroscopic ellipsometry, X‐ray photoelectron spectroscopy, and high‐resolution transmission electron microscopy. The degradation dynamics is found to be similar in air and under vacuum conditions, which leads to the conclusion that the occurrence of intrinsic thermodynamic mechanisms is not necessarily linked to humidity. The process has an early stage, which drives the starting tetragonal lattice in the direction of a cubic atomic arrangement. This early stage is followed by a phase change towards PbI2. We describe how this degradation product is structurally coupled with the original MAPbI3 lattice through the orientation of its constituent PbI6 octahedra. Our results suggest a slight octahedral rearrangement after volatilization of HI+CH3NH2 or MAI, with a relatively low energy cost. Our experiments also clarify why reducing the interfaces and internal defects in the perovskite lattice enhances the stability of the material. 相似文献
38.
Paolo Della Porta Riccardo Zanasi Guglielmo Monaco 《Journal of computational chemistry》2015,36(10):707-716
Current density plots of closed‐shell intermolecular H? H interactions characterized by a bond critical point (BCP) show two vortices separated by a saddle, a pattern which allows for a clear definition of a pair current strength. This H? H current strength turns out to be roughly related to the potential energy density at the BCP and then to the dissociation energy. The same pattern is also recognizable, at least for an azimuthal orientation of a field perpendicular to the H? H line, for the intramolecular interactions previously investigated to propose the H? H bonding. In the case of the H atoms of the bay region of polycyclic aromatic hydrocarbons, the current of the H? H delocalized diatropic vortex gives a quantitative indication of stabilization; however, on rotation of the field and the subsequent onset of a bay‐delocalized paratropic vortex (a typical signature of antiaromaticity), the diatropic vortex can be reshaped or it can even disappear, consistently with its smallness, and thus showing the effect of other more relevant interactions. © 2015 Wiley Periodicals, Inc. 相似文献
39.
Bruna P Baldi G Pineda E Serrano J Suck JB Crespo D Monaco G 《The Journal of chemical physics》2011,135(10):101101
Using high resolution inelastic x-ray scattering we studied the collective dynamics of the Pd(77)Si(16.5)Cu(6.5) metallic glass, focusing on the energy-momentum region where the boson peak appears. The dispersion relation and the width of the acoustic excitations are determined showing how the longitudinal acoustic modes maintain their dispersive character for frequencies well above the boson peak frequencies. Moreover, we prove that close to these frequencies there is a softening of the apparent sound speed indicating a failure of the Debye continuum approximation at the boson peak frequencies and challenging previous results on other metallic glasses. 相似文献
40.
Olson IA Bacon WA Baez Sosa YY Delaney KM Forte SA Guglielmo MA Hill AN Kiesow KH Langenbacher RE Xun Y Young RO Bowyer WJ 《The journal of physical chemistry. A》2011,115(40):11001-11007
We describe three new strategies for determining heterogeneous reaction rates using photomicroscopy to measure the rate of retreat of metal surfaces: (i) spheres in a stirred solution, (ii) microscopic powder in an unstirred solution, and (iii) spheres on a rotating shaft. The strategies are applied to indium-mediated allylation (IMA), which is a powerful tool for synthetic chemists because of its stereoselectivity, broad applicability, and high yields. The rate-limiting step of IMA, reaction of allyl halides at indium metal surfaces, is shown to be fast, with a minimum value of the heterogeneous rate constant of 1 × 10(-2) cm/s, an order of magnitude faster than the previously determined minimum value. The strategies described here can be applied to any reaction in which the surface is retreating or advancing, thereby broadening the applicability of photomicroscopy to measuring heterogeneous reaction kinetics. 相似文献