Coulomb distortions in heavy-ion reactions

In heavy-ion scattering the Coulomb potential deviates from the potential of two point charges since vibrations, rotations and giant resonances are excited in both projectile and target nuclei as a result of their mutual electrostatic forces. In this paper this effect is calculated using a classical model. The adiabatic and the dynamical solutions of the problem are compared and discussed.     

Oberfl?chenanalytik an Anlauffarben auf nichtrostenden St?hlen

Zusammenfassung Bei der kurzzeitigen Hochtemperaturbeaufschlagung nichtrostender Stähle (z.B. Durchlaufglühen, Schweißen) in Atmosphären mit verschiedenen O₂-Partialdrucken können oxidische Deckschichten entstehen, die eine solche Dicke erreichen, daß sie optisch wahrgenommen werden. Zusammenhängende Schichten sind häufig farbig. Dies ist überwiegend auf Interferenz, z.T. aber auch auf Absorption des Lichts zurückzuführen. Bei nicht zusammenhängenden inselförmigen Schichten entsteht der Eindruck eines Grauschleiers. Die Zusammensetzung der Schichten ist je nach Werkstoff, Temperatur und Atmosphäre sehr unterschiedlich nd kann im Detail nicht vohergesagt werden. Analytische Untersuchungen erfolgten mit ESCA und Mikro-AES. Wo es auf die Analyse farblich differenzierter Bereiche ankam, die sich im Kontrast im REM-Bild nicht unterschieden, wurde zusätzlich LAMMA eingesetzt. Diese Methode gestattet darüber hinaus den empfindlichen Nachweis auch der leichten Elemente bei hohem räumlichen Auflösungsvermögen.

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Surface analysis on stainless steels exhibiting annealing colours

Summary When stainless steels are exposed for short periods to high temperatures (as in welding and continuous annealing), oxide layers sufficiently thick to be visible may be formed in atmospheres with various O₂ partial pressures. Continuous layers are often coloured. This arises mainly from interference, but to some extent from absorption of the light also. Non-continuous layers consisting of islands give the surface an appearance of grey haze. The composition of the layers differs very much according to the material, temperature, and atmosphere, and cannot be accurately predicted. We investigated the layers analytically by ESCA and micro-AES. Where it was necessary to investigate differently coloured areas that could not be distinguished in the SEM picture, LAMMA was used also. This method additionally enables even the light elements to be detected very sensitively and gives high spatial resolution.

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Herrn Professor Dr. H. Hartmann zum 70. Geburtstag gewidmet     

Interpolation mit Intervallfunktionalen

Ohne Zusammenfassung     

Consideration of measurement error when using commercial indoor radon determinations for selecting radon action levels

An examination of year-long, in-home radon measurement in Colorado from commercial companies applying typical methods indicates that considerable variation in precision exsts. This variation can have a substantial impact on any mitigation decisions, either voluntary or mandated by law, especially regarding property sale or exchange. Both long-term exposure (nuclear track greater than 90 days), and short-term (charcoal adsorption 4–7 days) exposure methods were used. In addition, periods of continuous monitoring with a highly calibrated alpha-scintillometer took place for accuracy calibration. The results of duplicate commercial analysis show that typical results are no better than ±25 percent with occasional outliers (up to 5 percent of all analyses) well beyond that limit. Differential seasonal measurements (winter/summer) by short-term methods provide equivalent information to single long-term measurements. Action levels in the U.S. for possible mitigation decisions should be selected so that they consider the measurement variability; specifically, they should reflect a concentration range similar to that adopted by the European Community.     

Gauge-invariant poisson brackets for chromohydrodynamics

Noncanonical hamiltonian structures are presented both for Yang-Mills Vlasov plasmas, and for ideal fluids interacting with Yang-Mills fields. These hamiltonian structures are given Lie-algebraic interpretations.