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991.
992.
F. Frontera D. Dal Fiume T. Franceschini G. Landini E. Morelli M. Pamini A. Rubini S. Silvestri G. Spada E. Costa D. Cardini A. Emanuele 《Il Nuovo Cimento C》1984,7(6):656-672
Summary We describe a balloon experiment, currently in the marking, devoted to the observation of celestial X-ray sources. The main
features of the X-ray telescope are summarized as follows. It operates in the energy band from 20 to 300 keV. Its energy resolution
is about 17% at 60 keV. Under the hypothesis of 104 s of observing time, 3 mbar of residual atmospheric pressure and 3σ of statistical significance, the expected sensitivity
of the instrument is 2·10−6 photons/cm2 s keV in the (20÷200) keV energy band, corresponding to about 1 milliCrab. Its high sensitivity allows us to detect both
time variability in the flux and cyclotron lines in the spectra of X-ray sources. It has a field of view of 3° FWHM and has
the possibility of resolving complex fields by using multipitch modulation collimators. With such a configuration its angular
resolution is about 10′.
Paper presented at the 2° Convegno Nazionale di Fisica Cosmica, held at L'Aquila, 29 May–2 June 1984. 相似文献
993.
994.
995.
This problem (proposed for the 4th International Symposium on Applied Stochastic Models and Data Analysis) concerns an exploratory study related to the presently accepted hypothesis that temporal curves of the forced pulse luminescence of specialized blood cells, granulocytes, may indicate the level of effectiveness of the immunological system. This paper presents a new set of empirical data and an analysis of its structure. 相似文献
996.
997.
Barbara Glass 《The Journal of Mathematical Behavior》2004,23(4):429-442
Problem solving and justification of a diversified group of two-year college students was compared with approaches of younger elementary and secondary school students working on the same tasks. The students in this study were engaged in thoughtful mathematics. Both groups found patterns, justified that their patterns were reasonable and, utilized similar strategies for their solutions and methods of justification. They were also able to make connections and build isomorphisms among the various problems. 相似文献
998.
This paper describes thermal and/or palladium promoted pericyclic rearrangements of a pentaene ester. These transformations involve selective double bond isomerizations followed by electrocyclizations, affording a cyclohexadiene and a bicyclic[4.2.0] core resulting from a cyclic triene. 相似文献
999.
1000.
C. Dal Cappello J. Langlois M. C. Dal Cappello B. Joulakian A. Lahmam-Bennani A. Duguet R. Tweed 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,23(4):389-396
Electron-impact double ionization of noble gases is investigated theoretically for the case of high incident energies (5 keV). An ab initio calculation is made including partial correlation in the initial state as well as in the final state. The results of the calculations are compared with those of other theories and with the first available (e, 3e) experimental data on krypton 4p 6. 相似文献