Zur Bestimmung des Wolframs im Wolframstahl

Ohne Zusammenfassung     

Literatur

Ohne Zusammenfassung     

Zum Nachweis und zur Bestimmung des Titans

Ohne Zusammenfassung     

Magnetic properties of a ferrimagnetic core/shell nanocube Ising model: A Monte Carlo simulation study

Monte Carlo simulation has been used to study the magnetic properties and hysteresis loops of a single nanocube, consisting of a ferromagnetic core of spin- surrounded by a ferromagnetic shell of spin-1 with antiferromagnetic interface coupling. We find a number of characteristic phenomena. In particular, the effects of the shell coupling and the interface coupling on both the compensation temperature and the magnetization profiles are investigated. The effects of the interface coupling on the hysteresis loops are also examined.     

Lateral growth of microparacrystals in kevlar 49 fibers irradiated by Co60

Wide-angle x-ray diffraction experiments on Kevlar 49 fibers, irradiated with γ-rays from a Co⁶⁰ source, indicated that radiation-induced cross-linking in the form of H-bonding occurred within the microparacrystals (mPC) in the lateral direction b of the unit cell and had led to an increase in the mPC size in this direction. On the other hand, the mPC size I₂₀₀ along the axis and normal to the [200] netplanes did not change by radiation. In effect, the mPC size normal to the [110] netplanes increased from 4.23 nm to a maximum value of 6.04 nm at the 600 MRad dose level, after which it decreased. The mPC size in the direction of the fiber axis was 102 nm and did not change significantly by radiation (102–109 nm). Thus, essentially, the mPCs grew solely in the b direction. The paracrystalline distortion parameter (g) in the direction of the fiber axis was 2.8% and was not changed significantly by radiation (g = 2.9 ± 0.2%). The equatorial “crystallinity” maintained a value of 76% until a dose of 50 MRad and then became 73% at 100 MRad and 70% after this dose level The netplane distances were not affected by radiation.