Kollineationen und Schliessungssätze für Ebene Faserungen

Every affine central collineation of a translation plane induces a special collineation of the projective space spanned by the spreadF belonging to . Here the relations between these special collineations of and certain incidence propositions inF are investigated; so new proofs are given for some characterisations of (A,B)-regular spreads included in [7].     

Ergänzung zu “Über rationale Darstellungen von Kettengeometrien als projektive Varietäten”

Ohne ZusammenfassungAlle Bezeichnungen und Literatur wie dort.     

Über Kreisebenen mit Potenzlinie

Ohne Zusammenfassung     

Affine Kettengeometrien über Jordanalgebren

It is shown that an affine chain geometry over a Jordan algebra can be constructed in a nearly classical manner. Conversely, such chain geometries are characterized as systems of rational normal curves having a group of automorphisms with certain properties.

Herrn Prof. Dr. Heinz Lüneburg zu seinem 60. Geburtstag     

Über die Gruppe der Projektivitäten einer Geraden auf sich in einigen endlichen Fastkörperebenen

Ohne Zusammenfassung     

Büschelsätze zur Charakterisierung projektiv darstellbarer Zykelebenen

Ohne Zusammenfassung     

Eine Beziehung zwischen Regularitätsbedingungen für Faserungen

This is the proof of a theorem which states a relation between some regularity conditions for spreads.     

Magnetic microstructure of nanocrystalline FeCuNbSiB soft magnets

The soft magnetic properties and the domain patterns of optimized nanocrystalline FeCuNbSiB-alloys are typically comparable to those of highly permeable Co-based amorphous alloys. Yet the nanocrystalline alloys show some specific peculiarities absent in the amorphous case. The most prominent example is patchy magnetization patterns which reflect the residual contribution of the averaged random magneto-crystalline anisotropy to the magnetization process. The article surveys the typical characteristics and the consequences for the magnetization process.     

The influence of Cu and Nb on the crystallization products of annealed FeCuNbSiB

Depending on different Nb and Cu concentration, we studied the formation of nano- and microcrystalline phases in differently annealed samples of FeCuNbSiB. First, the kinetics of crystallization was explored by measuring the temperature-dependent electrical resistivity and magnetization. After this, we collected Mössbauer spectra and did an X-ray diffraction analysis of annealed samples at chosen temperatures to discover the different crystalline phases. It was found how the onset of crystallization had been shifted towards other temperatures. The analysis of Mössbauer spectra shows that building up the well-known DO₃ structure of Fe₃Si is disturbed in the alloy without Cu. At higher Nb content, we resolve two different crystallization steps in the formation of Fe₃Si and a new crystalline phase, probably being a structure like Fe₂₃B₆.