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101.
J. Hubele P. Kreutz J. C. Adloff M. Begemann-Blaich P. Bouissou G. Imme I. Iori G. J. Kunde S. Leray V. Lindenstruth Z. Liu U. Lynen R. J. Meijer U. Milkau A. Moroni W. F. J. Müller C. Ngô C. A. Ogilvie J. Pochodzalla G. Raciti G. Rudolf H. Sann A. Schüttauf W. Seidel L. Stuttge W. Trautmann A. Tucholski 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(3):263-270
We have studied the fragmentation of Au projectiles interacting with targets of C, Al and Cu at an incident energy ofE/A=600 MeV. The employed inverse kinematics allowed a nearly complete detection of projectile fragments with chargeZ≧2. The recorded fragmentation events were sorted according to three observables, the multiplicityM lp of light charged particles, the largest atomic numberZ max within an event, and a new observable,Z bound, representing the sum of the atomic numbersZ of all fragments withZ≧2. Using these observables, the impact parameter dependence of the fragmentation process was investigated. For all three targets, a maximum mean multiplicity of 3 to 4 intermediate mass fragments (IMFs) is observed. The corresponding impact parameters range from central collisions for theC target to increasingly peripheral collisions for the heavier targets. It is found that the correlation between the IMF multiplicity andZ bound, extending from evaporation type processes (largeZ bound) to the total disassembly of the projectile (smallZ bound), is independent of the target nucleus. This universal behaviour may suggest an — at least partial — equilibration of the projectile fragment prior to its decay. 相似文献
102.
103.
Margarete M. Brudny Wolfgang Rybczynski Wolfhart Seidel Dieter Thiel 《Mikrochimica acta》1990,102(1-3):71-78
The emission of various positive secondary ions has been investigated for polycrystalline targets of Ti, V, Cr, Nb, Ta, Co, Ni, Cu, Pd and Pt, which were bombarded by Ar+ ions under dynamic SIMS (DSIMS) conditions in the presence of the gaseous nitrogen oxides N2O, NO and NO2 at fixed pressure and under residual gas. Besides ions of the Me+ type several fragmentary ions (e.g. N+, O+, NO+, MeN+ and MeO+) and also cluster ions Me
x
O
y
+
(x 2, 0 y 2) were detected. Signals of a more molecular type with respect to the reactant gas, e.g. MeNO+, were only found for Co, Ni, Cu, Pd and Pt. From this, one may infer that for the other targets the nitrogen oxides will exist preferentially in a dissociatively adsorbed state at the metal surface. Several aspects of secondary ion emission can be explained assuming a different degree of oxidation for the metals under the influence of reactant gas.Part of the dissertation 相似文献
104.
105.
106.
107.
Heidrun Seidel 《Probability Theory and Related Fields》1979,47(3):231-240
Ohne Zusammenfassung 相似文献
108.
Ruth K Dinnebier RE Tönnes SW Alig E Sänger I Lerner HW Wagner M 《Chemical communications (Cambridge, England)》2005,(27):3442-3444
Solvent-free [LiCH2SMe]infinity forms a layer structure consisting of four- (Li2C2), five- (Li2CS2), and six-membered (Li2C2S2) rings in the solid state; the compound violently explodes upon heating to T=160+/-5 degrees C under an argon atmosphere. 相似文献
109.
110.