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11.
M.N. Armenise C. Canali M. De Sario A. Carnera P. Mazzoldi G. Celotti 《Journal of Non》1982,47(2):255-257
The Ti oxidation and the formation of a surface Ti-Nb-O compound occurring during Ti diffusion process in LiNbO3 for fabricating optical waveguides have been analysed using backscattering spectrometry and glancing-angle X-ray diffraction. Results show that Ti oxidation partially occurs owing to Ti reaction with oxygen atoms of the substrate and that the Ti-Nb-O compound grows epitaxially and behaves as a real source for Ti diffusion. 相似文献
12.
W. Wittek M. Aderholz P. Allport N. Armenise J. P. Baton M. Berggren F. W. Bullock M. Calicchio E. F. Clayton T. Coghen A. M. Cooper-Sarkar O. Erriquez P. Fitch N. Giannakopoulos J. Guy E. Hoffmann P. O. Hulth G. T. Jones P. Kasper U. F. Katz J. Kern H. Klein P. Marage E. Matsinos D. R. O. Morrison M. Neveu M. A. Parker N. Schmitz E. Simopoulou K. Varvell A. Vayaki W. Venus H. Wachsmuth BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,40(2):231-251
The average multiplicities of charged hadrons and of π+, π? and π0 mesons, produced in \(\bar v\) Ne and νNe charged current interactions in the forward and backward hemispheres of theW ±-nucleon center of mass system, are studied with data from BEBC. The dependence of the multiplicities on the hadronic mass (W) and on the laboratory rapidity (y Lab) and the energy fraction (z) of the pion is also investigated. Special care is taken to determine the π0 multiplicity accurately. The ratio of average π multiplicities \(\frac{{2\left\langle {n_{\pi ^O } } \right\rangle }}{{[\left\langle {n_{\pi ^ + } } \right\rangle + \left\langle {n_{\pi ^ - } } \right\rangle ]}}\) is consistent with 1. In the backward hemisphere \(\left\langle {n_{\pi ^O } } \right\rangle \) is positively correlated with the charged multiplicity. This correlation, as well as differences in multiplicities between \(\mathop v\limits^{( - )} \) and \(\mathop v\limits^{( - )} \) , \(\mathop v\limits^{( - )} \) scattering, is attributed to reinteractions inside the neon nucleus of the hadrons produced in the initial \(\mathop v\limits^{( - )} \) interaction. 相似文献
13.
K. Varvell A. M. Cooper-Sarkar M. A. Parker R. A. Sansum M. Aderholz N. Armenise J. P. Baton F. W. Bullock M. Berggren D. Bertrand V. Brisson W. Burkot M. Calcchio E. F. Claytoh T. Coghen O. Erriquez P. J. Fitch G. Gerbier J. Guy P. O. Hulth G. Iaselli G. T. Jones P. Kasper H. Klein C. Kochowski P. Marage M. Mermikides R. P. Middleton D. R. O. Morrison M. M. Mobayyen S. Natali M. Neveu S. Nuzzo S. W. O'Neale P. Petiau A. Petrides F. Ruggieri J. Sacton E. Simopoulou C. Vallee A. Vayaki W. A. Venus H. Wachsmuth J. Wells W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,36(1):1-13
The isoscalar nucleon structure functionsF 2(x, Q 2) andxF 3(x, Q 2) are measured in the range 0<Q 2<64 GeV2, 1.7<W 2<250 GeV2,x<0.7 using ν and \(\bar v\) interactions on neon in BEBC. The data are used to evaluate possible higher twist contributions and to determine their impact on the evaluation of the QCD parameter Λ. In contrast to previous analyses reaching to such lowW 2 values, it is found that a low \(\Lambda _{\overline {MS} } \) value in the neighbourhood of 100 MeV describes the data adequately and that the contribution of dynamical higher twist effects is small and negative. 相似文献
14.
15.
Fabrizio Esposito Iole Armenise Giulia Capitta Mario Capitelli 《Chemical physics》2008,351(1-3):91-98
A complete set of V–T (vibration–translation) relaxation rates and of dissociation coefficients for the system O–O2 have been obtained by using quasiclassical trajectories on the Varandas and Pais potential energy surface. The results, averaged on a Boltzmann rotational distribution, cover the whole range of the vibrational ladder and are reproduced in closed form ready to be implemented in state-to-state kinetic models. The accuracy of the results has been tested by comparing them with available experimental and theoretical values (ASI-CAST project is acknowledged). 相似文献
16.
We studied neural interactions between brain areas involved in exogenous (stimulus-driven) control of visuospatial attention. With event-related functional magnetic resonance imaging (fMRI), we investigated changes of connectivity during shifts of spatial attention from an attended location to a previously unattended target location. Using a 3-T scanner, fMRI data were acquired from three healthy volunteers. According to a central visual cue, participants directed endogenous spatial attention to the left or the right visual hemifield for blocks of 56 s. Peripheral visual targets were presented unpredictably in either the attended hemifield (valid trials, 80%) or in the unattended hemifield (invalid trials, 20%) and participants performed a two-alternative forced-choice discrimination task with the target, irrespective of cue validity. In accordance with previous results, we found that the temporal–parietal junction (TPJ) mediates the shift of spatial attention toward stimuli presented at the unattended side (i.e., invalid trials). We critically studied the interaction between occipital areas responding to the visual stimuli and other brain regions in order to find regions functionally coupled with the occipital cortex during invalid trials. We found that the coupling between occipital areas processing visual stimuli and the TPJ selectively increased during invalid trials. Our results highlight how changes of connectivity between brain areas can describe attentional processes such as stimulus-driven shifts of spatial attention. 相似文献
17.
Massimo Bovenzi Francesca Rui Flavia D’Agostin Sandra Bianchi GianLuca Festa Iole Pinto Nicola Stacchini 《Journal of sound and vibration》2006,298(3):514-539
The prevalence of low back pain (LBP) was investigated in 598 Italian professional drivers exposed to whole-body vibration (WBV) and ergonomic risk factors (drivers of earth moving machines, fork-lift truck drivers, truck drivers, bus drivers). The control group consisted of a small sample of 30 fire inspectors not exposed to WBV. Personal, occupational and health histories were collected by means of a structured questionnaire. Vibration measurements were performed on representative samples of the machines and vehicles used by the driver groups. From the vibration magnitudes and exposure durations, alternative measures of vibration dose were estimated for each subject. Daily vibration exposure, expressed in terms of 8-h energy-equivalent frequency-weighted acceleration, A(8), averaged 0.28-0.61 (range 0.10-1.18) m s−2 rms in the driver groups. Duration of exposure to WBV ranged between 1 and 41 years. The 7-day and 12-month prevalence of LBP was greater in the driver groups than in the controls. In the professional drivers, the occurrence of 12-month LBP, high intensity of LBP (Von Korff pain scale score ?5), and LBP disability (Roland & Morris disability scale score ?12) significantly increased with increasing cumulative vibration exposure. Even though several alternative measures of vibration exposure were associated with LBP outcomes, nevertheless a more regular trend of association with LBP was found for vibration dose expressed as ∑aviti (m s−2 h), in which the frequency-weighted acceleration, av, and lifetime exposure duration, t, were given equal weight. In multivariate data analysis, individual characteristics (e.g. age, body mass index) and a physical load index (derived from combining manual materials handling and awkward postures) were significantly associated with LBP outcomes, while psychosocial work factors (e.g. job decision, job support) showed a marginal relation to LBP. This study tends to confirm that professional driving in industry is associated with an increased risk of work-related LBP. Exposure to WBV and physical loading factors at work are important components of the multifactorial origin of LBP in professional drivers. 相似文献
18.
N. Armenise M. Calicchio O. Erriquez M.T. Fogli-Muciaccia S. Natali S. Nuzzo F. Romano R. Belusevic D.C. Colley G.T. Jones S. ONeale S.J. Sewell M.F. Votruba D. Bertrand J. Moreels J. Sacton C. Vander Velde-Wilquet M.A. Parker 《Physics letters. [Part B]》1981,102(5):374-380
Charged-current neutrino interactions have been analysed in a sample of pictures from BEBC equipped with a TST. Using a method independent of both the neutrino flux and nuclear interaction corrections, the ratio R= σn/σp has been measured. The result is R=1.98±0.19 for the ratio of total cross sections. Bjorken x distributions for proton and neutron targets and for u and d quarks are compared. 相似文献
19.
N. Armenise M.T. Fogli-Muciaccia F. Romano M. Haguenauer C. Matteuzzi J.P. Vialle M. Willutzky S. Bonetti D. Cavalli A. Pullia S. Ragazzi M. Rollier G. Carnesecchi P. Heusse C. Pascaud 《Physics letters. [Part B]》1981,100(2):182-184
The ν events collected in “Gargamelle” exposed at the CERN SPS wide band beam are reanalyzed to search for possible νμ → νe oscillations. No effect is found and an upper limit of 1.2 eV at 68% c.l. is determined for the mass parameters in the case of maximum neutrino mixing. A limit on the νμ → ντ transition probability is also quoted, but the sensitivity is smaller. 相似文献
20.
N. Armenise M.T. Fogli-Muciaccia S. Nuzzo J.P. Albanese A. Bouchakour P. Musset Ph. Busson B. Degrange U. Nguyen-Khac S. Bonetti D. Cavalli A. Pullia G. Carnesecchi Ph. Heusse J. Sleeman 《Physics letters. [Part B]》1981,104(5):409-415
Evidence for charmed baryon “elastic” production is found in a sample of 55 000 charged-current neutrino interactions in the bubble chamber Gargamelle exposed to the SPS wide-band neutrino beam. The product of the average cross section times the branching ratio into modes including a Λ0 or a 0p system is found to be α·B=(14.3 ± 7.4) × 10?40 cm2 for ν+n reactions and α · B<3.3×10?40 cm2 (90% CL) for ν+p reactions. 相似文献