IR-Spektralanalyse von Gl?sern des Systems TeO2?V2O5

Studies of glasses and their crystalline products in the TeO₂–V₂O₅ system were made in the 1400–400 cm^–1 range. A continuous shift of the V=O-band from 1020 cm^–1 to 940 cm^–1 was found in the glasses with decreasing concentration of V₂O₅, as well as a sharp decrease in the intensity at 830 cm^–1. On the basis of the results obtained, it is concluded that with increasing TeO₂ content, the structure of the glasses is changed, caused by the breaking of the V–O–V bonds and the formation of Te–O–Te bridges.The IR-spectrum of the 2TeO₂·V₂O₅ compound in both crystalline and vitreous states was studied for the first time. The behaviour of the absorption bands is related to the structure of the glasses studied.     

Die Algebra des Isotopen Spins (3/2, 1/2)

Zusammenfassung Alle irreduziblen Systeme von n hermitischen Matrizen _j, die den zyklischen Vertauschungsrelationen dritten Grades (s. Gl. (14)) genügen, werden explizite aufgefunden. Es zeigt sich insbesondere, dass bei n=3nur zwei solche nichttriviale Lösungen existieren, eine sechsreihige und eine vierreihige. Die erste ist mit dem von Votruba und Lokajíek zwecks Beschreibung des Verhaltens des isotopen Spins des Nukleons eingeführten Matrixsystem äquivalent. Die zweite Lösung erfüllt zugleich auch die Kemmerschen Relationen. Für jedes n>3gibt es nur je eine nichttriviale Lösung, nämlich die Kemmersche von der Ordnung N=n+1.     

Regional cooperation in proficiency testing: strategy planning and practical experiences in Western Balkan countries

The article describes the project of regional cooperation in proficiency testing within CARDS 2006 (assistance programme to the Western Balkans), which was coordinated by European Committee for Standardization, European Commission and European Free Trade Association and conducted by the University of Ljubljana, Faculty of Electrical Engineering, Laboratory of Metrology and Quality. The later is the holder of the national standard for thermodynamic temperature as well as an accredited proficiency testing provider and also accredited as a calibration, testing and inspection laboratory. It is also responsible for graduate study programme Quality Engineering. Proficiency testing was considered as a core activity of the entire project, but additionally as a very appropriate platform for knowledge transfer of EU technical legislation in selected sectors, metrology, testing and quality assurance in general. The project had a high added value for participating laboratories in countries of Western Balkans, because it required an active role of all participating laboratories, assured participation of staff from national metrology institutions, all national accreditation bodies, and was supported by national quality infrastructures, such as standardization, governmental institutions etc. in the entire Western Balkans region. The activities stimulated progress in the area of conformity assessment, added knowledge to the implementation of technical directives and development of the technical part of national legislation and therefore facilitated the process toward the accession to the European Union. The main objective was therefore to organize proficiency testing in those sectors (construction, consumer protection and environment) that were vital in the pre-accession process of countries seeking full implementation of EU technical legislation.     

Minimal non-quaternion-free finite 2-groups

We classify minimal non-quaternion-free finite 2-groups which possess a nonmodular proper subgroup.     

Still more on proton decay in supersymmetric theories

It is shown, contrary to the recent claim in literature, that gluino exchange in supersymmetric proton decay does not vanish in general. In N=1 supergravity theory it could be an important or even dominant contribution, which would imply the often-mentioned model independent main mode . We also summarize the situation in the case of charged W-ino exchange incorporating the new measurement of B meson lifetimes.