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991.
H. -G. Clerc W. Lang H. Wohlfarth K. -H. Schmidt H. Schrader K. E. Pferdekämper R. Jungmann 《Zeitschrift für Physik A Hadrons and Nuclei》1975,274(3):203-213
The mass separated fission product beam provided by the mass separator “Lohengrin” has been used to determine the nuclear charge distribution for the thermal-neutron-induced fission of235U for all light fission products in the region 80≦A≦107. The measurements were performed at the most probable kinetic energy of the fission products. By using the known fission product mass yields, the independent yields for a total number of 100 nuclides were obtained under the condition of the most probable kinetic energy. The proton pairing effect modulates the average nuclear charge of the fission fragments and the isobaric charge distribution widths in a regular fashion. The probabilities of breaking a pair and of forming fragments with an energetically unfavourable neutron-to-proton ratio are found to compete with each other. Both probabilities depend on the mass split and reach their maximum values in the region of the most probable masses. The odd-even-proton effect is found to vary smoothly between 16% for the most abundant mass splits and 40% for the rare mass splits. The odd-even-neutron effect exhibits maxima nearN=50 andN=60, where it reaches 16%. These maxima and the extremely low Tcyield (0.13±0.05%) are discussed with regard to fragment shell effects. 相似文献
992.
993.
Göran Fäldt 《Annals of Physics》1983,148(2):327-345
Various symmetries of inelastic proton-nucleus scattering within the Glauber model are discussed. They are obtained from symmetries of the corresponding proton-nucleon amplitude. In particular, it is shown that the polarization and analyzing power are in general not equal. 相似文献
994.
We report on the observation of Kαα X-rays of Si, produced in collisions of 15–28 MeV Si projectiles with various target atoms in the range Z = 6 to 29. Energy shifts of X-rays were measured and are compared with theoretical predictions. Cross section ratios for emission of Kαα and Kα radiation are given. 相似文献
995.
996.
Z- as well as E-isomers of 1,2-diarylbutadienes undergo Diels-Alder reactions with nitrosobenzenes regiospecifically, but the adducts have different structures (3 or 4, respectively) in both cases. From kinetic results it is concluded that the somewhat anomalous cycloaddition of the E-isomers is facilitated and directed by the intermediate formation of a CT-complex. 相似文献
997.
The angular resolved energy distribution of true secondary electrons emitted normal to a clean W(100) surface has been measured with a 180° Spherical Deflector Analyzer. While significant discrepancies are found with earlier secondary emission data, good agreement exists with angular resolved photoemission spectra. Comparison to recent band structure calculations (density of states effects) is made. The fine structure of the secondary emission spectrum is fully explained by numerical results obtained by means of a quantitative theory of angular resolved secondary emission. Further, the fine structure corresponds closely to reflection coefficient data. 相似文献
998.
W. Wölfli Ch. Stoller G. Bonani M. Stöckli M. Suter W. Däppen 《Zeitschrift für Physik A Hadrons and Nuclei》1978,286(3):249-252
Anisotropy spectra of the MOK X-ray transitions have been measured in F-Al, Al-Al and Cl-Al collisions as a function of the projectile energy. The measurements at higher energies indicate a new molecular effect due to transitions from quasicontinuum states to the MO 1s σ-orbitals. 相似文献
999.
1000.
The paper deals with the influence of a magnetic field on the function of a thermionic energy converter. It derives a relation for the effect of the magnetic field on the converter current in a diffusion regime and gives measurements for a quasi-vacuum and diffusion regime of the converter. 相似文献