Some Properties of -open Sets
A coating for improved resistance welding of galvanized steel parts or sheets comprises a binder, and a metal phosphide pigment, preferably a ferrophosphorus pigment, having a particle size of from about 0.1 to about 30 microns. The pigment can also include up to about 40% by weight of an additional metal such as tin, aluminum or lead, which can be combined with the metal phosphide in pigment form or deposited onto the surface of the particles. The coating can be applied to either the faying or non-faying surfaces of the galvanized steel, or to the resistance welding electrode, and may be removed, if desired, after the welding operation. The advantages of the present invention include a significant reduction in welding current and an increase in the weldability lobe width, a restoration of the dynamic resistance beta peak, and an increase in electrode life.
δ-closure, θ-closure and generalized closed sets
We study some new classes of generalized closed sets (in the sense of N. Levine) in a topological space via the associated δ-closure and θ-closure. The relationships among these new classes and existing classes of generalized closed sets are investigated. In the last section we provide an extensive and more or less complete survey on separation axioms characterized via singletons.
SR topography of plastically deformed Fe-Si bicrystals - observation in situ and post mortem
SR reflection topography was applied to study the interaction of slip dislocations with the grain boundaries in Fe-4at%Si bicrystals deformed by compression. Three experimental settings with either a white or monochromatic beam were used and the corresponding orientation contrast analysed. Dislocation transmission through the grain boundary was observed in bicrystals with favourable geometry of the slip systems.