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The decomposition of formic acid vapor by 2.783 μm infrared radiation from a pulsed HF laser has been studied at pressures from 1.6 to 44 torr temper 相似文献
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Differential cross sections have been measured for the elastic scattering of 217 MeV 3He particles from 6Li, 9Be, 12C, 28Si, 40Ca, 58Ni, 89Y, 90Zr, 120Sn and 208pb. The data have been analysed with an optical potential. The ambiguities found at lower energies (discrete families of real potential well depths) disappear. An optical potential is also calculated with an effective 3He-N interaction and a matter distribution. The agreement with experiment is good. Some comparisons are made with 166 MeV α-particle elastic scattering data. 相似文献
186.
The region of the giant resonances in 208Pb has been investigated by inelastic scattering of 201 MeV protons. To test the analysis, angular distributions were measured for the low-lying 3?, 5?, 2+ and 4+ collective states. The giant isoscalar quadrupole resonance (ISGQR) is split into two structures, one at 9.0 MeV with a full width at half-maximum Γ = 1.0 MeV, the other one at 10.6 MeV (Γ = 2.0 MeV), with fine structures at 8.9, 9.3, 10.1, 10.6 and 11 MeV. A macroscopic analysis using the distorted-wave Born approximation (DWBA) leads for the low-lying collective levels, as well as for the ISGQR, to transition probabilities too small by a factor of two, compared with those obtained in other reactions. Microscopic analysis using the distorted-wave impulse approximation (DWIA), with three different sets of random phase approximation (RPA) transition densities, is in very good agreement with the data. At forward angles, in the 12 to 16 MeV excitation energy region, a strong resonance at 13.5 MeV (Γ = 3.6 MeV) is accounted for by the Coulomb excitation of the isovector giant dipole resonance (IVGDR); at larger angles the results are compatible with the excitation of the isoscalar monopole resonance (ISGMR) located at 13.9 MeV (Γ = 2.6 MeV).A resonance located at 21.5 MeV (Γ = 5.7 MeV) appears as the superposition of an isovector quadrupole resonance (IVGQR) excited by Coulomb interaction and a resonance of multipolarity L = 1 ΔT = 0 (ISGDR “squeezing mode”). 相似文献
187.
The problem of minimising the overall duration of a project subject to constraints on the availability of resources is considered with particular reference to the use of branch and bound methods. A new resource based bound, new dominance rules and an innovatory network breakdown technique which preserves optimality are reported. Computational experience and comparisons with schedules obtained by decision rule methods are given. 相似文献
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C. Kourkoumelis L.K. Resvanis T.A. Filippas E. Fokitis A.M. Cnops S. Iwata R.B. Palmer D.C. Rahm P. Rehak I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli P. Mouzourakis A. Nappi W.J. Willis M. Goldberg G.C. Moneti 《Nuclear Physics B》1979,158(1):39-56
Correlations of two π0 mesons with transverse momenta up to 10 GeV/c have been measured utilizing apparatus with large azimuthal acceptance. The data are analysed in the context of constituent scattering models, and also compared with a simple “back-ground” hypothesis. 相似文献