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201.
Artur Oscar Lopes 《Journal of statistical physics》1988,52(3-4):571-575
The exact complex potential generated by the maximal measure for a family of rational maps is given. The results are of analytical nature because the complex potential does not change nicely if the coordinates of a rational map are changed. There exist applications of this result to the theory of moments. 相似文献
202.
D. Allasia C. Angelini A. Baldini L. Bertanza F. Bianchi A. Bigi F. Bobisut A. Borg P. Capiluppi R. Cirio J. Derkaoui M. L. Faccini-Turluer A. G. Frodesen D. Gamba G. Giacomelli B. Jongejans G. Mandrioli A. Margiotta-Neri A. Marzari-Chiesa R. Pazzi L. Patrizii C. Petri F. Predieri A. Romero A. M. Rossi A. Sconza P. Serra-Lugaresi M. Spurio A. G. Tenner G. W. van Apeldoorn P. H. A. van Dam N. A. M. van Eijndoven D. Vignaud WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,37(4):527-533
Bose-Einstein correlations between pions of equal charge have been observed in Charged Current and Neutral Current (anti)neutrino-deuterium interactions in the BEBC bubble chamber exposed to the SPS wide band beam. The pion emission region is found to be essentially spherical with a mean radius of (0.48±0.07) fm; the chaoticity parameter is 0.36±0.04. 相似文献
203.
Beatriz Veleirinho Manuel F. Rei J. A. Lopes‐DA‐Silva 《Journal of Polymer Science.Polymer Physics》2008,46(5):460-471
This study describes the preparation and characterization of nanofibrous mats obtained by electrospinning poly(ethylene terephthalate) (PET) solutions in trifluoroacetic acid/dichloromethane (TFA/DCM). Special attention was paid to the effect of polymer concentration and solvent properties on the morphology, structure, and mechanical and thermal properties of the electrospun nonwovens. The results show that the spinnable concentration of PET solution in TFA/DCM solvents is above 10 wt %. Mats have nanofibrous morphology with fibers having an average diameter in the range of 200–700 nm (depending on polymer concentration and solvent composition) and an interconnected pore structure. Higher solution concentration favors the formation of uniform fibers without beads and with higher diameter. Morphology and fiber assembly changed with the solvent properties. Solvent mixtures rich in TFA, i.e., those with higher dielectric constant and lower surface tension, originated fibers with small diameter. However, due to the lower volatility, those solvent mixtures also produced more branched and crosslinking fibers, with less morphologic uniformity. Mechanical properties (Young's modulus, ultimate strength, and elongation at break) and thermal properties (glass transition, crystallization, and melting) have been studied for the PET electrospun nanomats and compared with those of the original polymer. Solvent effect on fiber crystallinity was not significant, but a complex effect was observed on the mechanical properties of the electrospun mats, as a consequence of the different structural organization of the fibers within the mat network. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 460–471, 2008 相似文献
204.
Summary In this paper we study a model system of2×2 second order, linear variational inequalities in which the solution is subjected to a unilateral constraint, the obstacle. We obtain existence for some systems which are not strongly elliptic, and we give an example of non- uniqueness in a specific case.Research supported in part by FAPESP Grant 93/3732-7. 相似文献
205.
M. Bonesini E. Bonvin P. S. L. Booth R. Bopp L. J. Carroll A. J. Cass D. Cavalli S. U. Chung G. Costa M. Donnat P. A. Dorsaz E. Durieux M. E. J. Feliks J. R. Fischer L. Fluri F. Gianotti S. Jack J. N. Jackson M. Kelly M. N. Kienzle-Focacci R. Lucock J. G. Lynch L. Mandelli M. Martin L. Mathys A. Maxwell M. Mazzanti P. J. Negus L. Perini D. Perrin G. Polesello R. Poultney W. H. Range L. Rosselet S. W. Snow A. S. Thompson R. M. Turnbull M. Werlen WA -Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,42(4):527-532
The inclusive cross sections for η production by the interactions of 280 GeV/c momentum π?, π+, and proton beams in hydrogen have been measured. The kinematical range covered is ?0.45<x F <0.45, and 4.0<P T <7.0 GeV/c for Feynmanx F and transverse momentum respectively. The η to π0 cross section ratios are given for the three reactions. The ratio of π? p to π+ p cross sections for η production in the above kinematic ranges is 1.22±0.08±0.11. 相似文献
206.
We analyse the proton electromagnetic form factor ratioR(Q 2 ) =QF 2 (Q 2 )/F 1 (Q 2 ) as a function of momentum transferQ 2 within perturbative QCD. We find that the prediction for (R(Q 2 ) at large momentum transferQ depends on the exclusive quark wave functions, which are unknown. For a wide range of wave functions we find thatQF 2 F 1 ~ const. at large momentum transfer, which is in agreement with recent JLAB data. 相似文献
207.
208.
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
209.
Brereton Richard G. Jansen Jeroen Lopes João Marini Federico Pomerantsev Alexey Rodionova Oxana Roger Jean Michel Walczak Beata Tauler Romà 《Analytical and bioanalytical chemistry》2018,410(26):6691-6704
Analytical and Bioanalytical Chemistry - The contribution of chemometrics to important stages throughout the entire analytical process such as experimental design, sampling, and explorative data... 相似文献
210.