Structure and topology of a brittle-ductile fault swarm at Crawford Knob, Franz Josef, New Zealand

Franz Josef Kallmann (1897?1965)

Franz Josef Kallmann studied the biological and genetic factors of psychological disorders in Germany and the United States in the twentieth century. His studies at the New York State Psychiatric Institute in New York City, New York, focused on the genetic factors that cause psychiatric disorders. Kallmann was one of the first to use twins to study how a mental disorder is passed on by comparin...

Declining soil fertility does not increase leaf lifespan within species: evidence from the Franz Josef chronosequence, New Zealand

Leaf lifespan varies widely among plant species, from a few weeks to >40 years. This variation is associated with differences in plant form and function, and the distribution of species along resource gradients. Longer leaf lifespans increase the residence time of nutrients and are one mechanism by which plants conserve nutrients; consequently, leaf lifespan should increase within species with ...

Ductile or Partial Ductile Mode Machining of Brittle Materials

This paper reports ductile or partial ductile mode machining of silicon, glass and some advanced ceramics. Results are presented using scanning electron micrographs of the machined surfaces. Grinding and lapping operations using inexpensive machine tools could produce ductile streaks on surfaces of these brittle materials under good conditions. Manufacture of spherical glass lenses by the fract...

Franz - Josef Obermair , Aileen Schröter and Michaela Thallmair

Numerical Modeling of the Ductile-Brittle Transition

Numerical studies of the ductile-brittle transition are described that are based on incorporating physically based models of the competing fracture mechanisms into the material's constitutive relation. An elastic-viscoplastic constitutive relation for a porous plastic solid is used to model ductile fracture by the nucleation and subsequent growth of voids to coalescence. Cleavage is modeled in ...