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21.
A. L. S. Angelis J. Antos M. Beaulieu H. Beker G. Briskin J. Bystricky M. -G. Catanesi P. Cerello S. Dagan G. Dellacasa M. Diehl S. Di Liberto B. Dolgoshein M. Esten C. W. Fabjan A. Gaidot M. Gallio P. Giubellino U. Goerlach C. Guerra L. -A. Hamel S. Konovalov I. Kralik G. London F. Martelli J. -P. Martin M. Masera M. -A. Mazzoni F. Meddi M. -T. Muciaccia S. Muraviev A. Nomerotsky Y. Oren J. -P. Pansart G. Poulard L. Ramello L. Riccati G. Rosa L. Sandor M. Sarris E. Scomparin A. Shmeleva S. Simone S. Smirnov P. Taras J. Urban E. Vercellin 《The European Physical Journal C - Particles and Fields》1998,5(1):63-75
Results are presented on and production in p–W and S–W interactions at 200 GeV/c/nucleon measured via the dimuon decay in a large kinematic region. The data are normalized to
the charged particle multiplicity in the same rapidity interval. They have been collected using the HELIOS/3 muon spectrometer
at the CERN SPS. The ratio , where is the relevant resonance branching fraction, increases between proton and sulphur projectiles, and is somewhat enhanced going from peripheral to central
S–W interactions. This results from an increase in the number of produced 's per charged particle. The ratio is measured in different intervals of p and rapidity. It is not clearly dependent on p, but is larger at higher rapidities. production, likewise normalized to charged multiplicity, is significantly lower in S–W compared to p–W interactions.
Received: 27 October 1997 / Revised version: 5 March 1998 / Published online: 13 July 1998 相似文献
22.
O. Häusser H.R. Andrews D. Ward N. Rud P. Taras R. Nicole J. Keinonen P. Skensved C.V. Stager 《Nuclear Physics A》1983,406(2):339-368
We have determined the transient magnetic field for Coulomb-excited rare-earth nuclei recoiling with velocities in the range between 0.7ν0 and 6ν0 into ferromagnetic gadolinium cooled to a temperature T = 80 K. Measured and calculated g-factors in 169Tm have been used as calibration standards. The transient field is found at first to increase with increasing recoil velocity, and then to level off, approaching a nearly constant value of 5.5 kT at ν = 6ν0. At the higher velocities (3ν0 < ν < 6ν0) the transient fields for 169Tm recoils in gadolinium are a factor of 1.42 ± 0.12 larger than those in iron, whereas the densities of polarized electrons are the same in both ferromagnets. This result demonstrates that an explanation of the transient field must take into account the atomic structure of the host (and probably also that of the recoil). The transient field is too large to be described only in a statistical picture in which inner-shell (ns) vancancies are filled by capture of polarized (4f) electrons. Possible mechanisms may involve either polarization transfer from the outer shells by spin-flip interactions, or direct vacancy polarization by diabatic molecular orbitals.The transient field calibration has been corroborated making use of known g-factors of low-spin states in 156, 158, 160Gd populated by Coulomb excitation of thick Gd single crystals. For the high-spin states in these nuclei, the g-factors are found to decrease slightly, with the ratio ) reduced to 0.89±0.12, 0.83±0.11, and 0.93±0.13, respectively. Similar decreases have been observed previously for other N = 90?96 nuclei. 相似文献
23.
Stasyk T Morandell S Bakry R Feuerstein I Huck CW Stecher G Bonn GK Huber LA 《Electrophoresis》2005,26(14):2850-2854
Here we combine a standard two-dimensional difference gel electrophoresis (DIGE) protocol with subsequent post-staining of gels with phosphospecific fluorescent Pro-Q Diamond dye. The combination of these two methods for fluorescence detection of proteins allows quantitative detection of phosphoproteins in 2-DE-gels. We established this protocol within a functional proteomics experiment. Mammary epithelial cells (EpH4) were stimulated in culture by epidermal growth factor (EGF), endosomal fractions prepared after subcellular fractionation and phosphorylated proteins successfully detected on endosomes. For instance, Endo A cytokeratin, known as phosphoprotein and differentiation marker inducible by MAPK signaling, was identified by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). With this protocol, all steps of combined proteome and phosphoproteome profiling experiments are significantly simplified and accelerated, taking full advantage of both methods in terms of specificity, sensitivity and accuracy of quantification. 相似文献
24.
The energy, multipolarity and multiplicity spectra of the continuum gamma radiation feeding high-spin isomers in 148, 149, 151, 152Dy and 147Gd have been measured at several bombarding energies. The final nuclei were selected via a delayed coincidence technique while the use of a NaI(Tl) Compton shielded crystal allowed the primary gamma-ray spectra to be generated reliably from the observed spectra.It was found that: (i) the energy of both the gamma-ray statistical cascade and the neutron cascade increases with increasing excitation energy, the latter much more rapidly than expected; (ii) the multiplicity of gamma-ray cascades, in which a statistical transition was detected, is generally lower than that of the average cascade; (iii) stretched E2 spin-correlated transitions occur above and above , indicating the onset of collectivity at these spins — in addition, a region of predominantly dipole emitting states is located below ; (iv) effective moments of inertia derived from the bump edge are 50–100% larger than those deduced from the density of stretched E2 transitions in the bump; (v) in 149,151Dy the bump edge is very sharp but no multiplicity features are observed; (vi) although the four Dy isotopes were populated at approximately the same excitation energy, they display considerable differences in their continuum properties.Probable interpretations of these observations are discussed, in particular we have suggested that several of the observed effects are consistent with the possible presence of high-K collective bands above the yrast line. 相似文献
25.
We report on the observation of the excitation/emission spectrum of a dendrimer-encapsulated gold nanocluster; the synthesis of Au-PAMAM was based on reduction of HAuCl4 x 3 H2O co-dissolved in methanol together with fourth-generation OH-terminated PAMAM. 相似文献
26.
S. N. Avvakumov Yu. N. Kiselev M. V. Orlov A. M. Taras’ev 《Computational Mathematics and Modeling》2010,21(3):336-378
Production functions are used to model the production activity of enterprises. In this article, we formulate the necessary
and sufficient conditions of strict concavity for Cobb–Douglas and constant elasticity of substitution (CES) production functions.
These conditions constitute the theoretical foundation for analyzing the profit maximization problem. An optimal solution
is constructed in analytical form and some of its properties are described. Three approaches to solving the profit maximization
problem are considered and their equivalence is established. For a Cobb–Douglas production function we investigate the dependence
of the maximum profit on elasticity coefficients. A similar analysis is carried out also for the CES production function.
The article presents a systematic and detailed discussion of the relevant topics. The topic is related to the investigation
of innovation activity of enterprises. The theoretical results and the explicit analytical relationships provide a theoretical
and algorithmic base for the “Planer” optimization software—a useful product for the analysis of the production activity of
enterprises modeled by production function tools. 相似文献
27.
The class of metrizable spaces M with the following approximation property is introduced and investigated: M∈AP(n,0) if for every ε>0 and a map g:In→M there exists a 0-dimensional map g′:In→M which is ε-homotopic to g. It is shown that this class has very nice properties. For example, if Mi∈AP(ni,0), i=1,2, then M1×M2∈AP(n1+n2,0). Moreover, M∈AP(n,0) if and only if each point of M has a local base of neighborhoods U with U∈AP(n,0). Using the properties of AP(n,0)-spaces, we generalize some results of Levin and Kato-Matsuhashi concerning the existence of residual sets of n-dimensional Lelek maps. 相似文献
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Instability of the finite‐difference split‐step method applied to the nonlinear Schrödinger equation. II. moving soliton
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Taras I. Lakoba 《Numerical Methods for Partial Differential Equations》2016,32(3):1024-1040
We analyze a mechanism and features of a numerical instability (NI) that can be observed in simulations of moving solitons of the nonlinear Schrödinger equation (NLS). This NI is completely different than the one for the standing soliton. We explain how this seeming violation of the Galilean invariance of the NLS is caused by the finite‐difference approximation of the spatial derivative. Our theory extends beyond the von Neumann analysis of numerical methods; in fact, it critically relies on the coefficients in the equation for the numerical error being spatially localized. © 2015 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 1024–1040, 2016 相似文献