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991.
R. Bimbot D. Gardès H. Geissel K. H. Schmidt 《Zeitschrift für Physik A Hadrons and Nuclei》1978,286(3):327-328
The kinetic energy of86Kr ions accelerated by UNILAC (GSI-Darmstadt) was measured using the recoil proton technique. A good agreement was found with the energy values obtained by the time-of-flight technique currently used at UNILAC. 相似文献
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993.
The 42Ca(α, 3He)43Ca reaction has been studied at 36 MeV incident energy. Angular distributions have been measured from 4° to 42° using a split-pole spectrometer and position sensitive Si detectors, for about 40 levels located up to 6 MeV excitation energy. A local zero-range DWBA analysis has been carried out; l = 3 and 4 assignments are tentatively proposed for levels located above 4 MeV excitation energy, indicating a strong fragmentation of the strength between 4 and 6 MeV and the location of the main component of the strength above 6 MeV. A number of weakly excited levels cannot be reproduced by DWBA analysis. Their angular distributions have been compared with the results of coupled-reaction-channel calculations assuming two-step excitation of weak coupling states with a [42Ca1 ? structure. A reasonable agreement has been obtained, confirming that the two-step process cannot be neglected in the analysis of the (α, 3he) reaction. 相似文献
994.
M. Della Negra D. Drijard H.G. Fischer G. Fontaine H. Frehse P. Frenkiel G. Ghesquière R. Gokieli P. Hanke P.G. Innocenti W. Isenbeck E.E. Kluge V. Korbel S. Krzywdzinski D. Linglin A. Minten D.R.O. Morrison A. Putzer D. Wegener 《Physics letters. [Part B]》1975,59(4):401-404
Events with a positive particle of large transverse momentum emitted at medium angles have been studied using the split field magnet spectrometer at the CERN-ISR at a c.m. energy of √s = 52.5 GeV. Positive particles with large longitudinal momentum, |x| > 0.5, i.e., leading particles, associated to large pT events, are analysed. 相似文献
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The rotational strength of the longest-wavelength electronic transition in some simple γ-lactams and some related isoelectronic molecules is calculated using the CNDO-CI method. Qualitative agreement with experimental values is obtained. In all investigated systems the long-wavelength transition corresponds to the nπ* transition. A quadrant rule seems to hold for this transition. 相似文献
999.
“In-situ” monitoring activation and reaction on very absorbing catalytic solid by DRIFT spectrometer
Christophe Depecker Pierre Legrand Abdoulaye Sene Geneviève Wrobel 《Mikrochimica acta》1988,95(1-6):119-122
The FTIR's well-known advantages are strongly shown by the use of new infrared techniques. Both advantages of FTIR and diffuse reflectance make this coupling particularly important in the development of infrared studies.Sensitivity and rapidity of the FTIR spectrometer, added to the extremely simple preparation of the sample, allowed by diffuse reflectance attachment, give a high performing tool particularly in catalysis in the view of understanding the catalytic reactions mechanisms. We have chosen thein-situ study of two catalytic systems active in selective hydrogénation of dienes: a copper-chromium oxide and Cu/Al2O3
. 相似文献
1000.