We obtain, using the Birman-Schwinger method, a series of necessary conditions for the existence of at least one bound state applicable to arbitrary central potentials in the context of nonrelativistic quantum mechanics. These conditions yield a monotonic series of lower limits on the “critical” value of the strength of the potential (for which a first bound state appears) which converges to th...

Friction stir processing (FSP) 2519-T87 aluminum plate results in enhanced ductility, 25% strain at fracture. However, the yield strength in the FSP zone drops to 175 MPa from �400 MPa. Actively cooling the plate during FSP increases the yield strength to 185 MPa and decreases ductility to 20% strain at fracture. Thick bending of a plate of the alloy was demonstrated after the surface was subje...

In this study, bulk ultrafine-grained and micro-crystalline cobalt was prepared using a combination of high-energy ball milling and subsequent spark plasma sintering. The average grain sizes of the ultrafine-grained and micro-crystalline materials were 200 nm and 1 μm, respectively. Mechanical properties such as the compressive yield strength, the ultimate compressive strength, the maximum comp...

the objective of the present work is to analyse the potential of using non-classical additions in concrete and mortar compositions such as coal bottom ash (ba) and biomass ash (bio), as partial replacing binder of ordinary portland cement. it is intended to deal with production of these type of wastes and its accumulation and contribute to the minimisation of carbon and embodied energy in const...

The correlation between the strength at the macroscale and the elastic deformation as well as shear cracking behavior at the microscale of bulk metallic glasses (BMGs) is investigated. The temperatures of 298 K and 77 K as well as the strain rate ranging from 10(-6) s(-1) to 10(-2) s(-1) are applied to the BMGs, in which the mechanical responses of the BMGs are profiled through the compression ...