The material flow and microstructural evolution in the friction stir welds of a 6061-Al alloy to itself and of a 6061-Al alloy to 2024-Al alloy plates of 12.7 mm in thickness were studied under different welding conditions. The results showed that plastic deformation, flow, and mechanical mixing of the material exhibit distinct asymmetry characteristics at both sides of the same and dissimilar ...

−A packed bed external loop airlift bioreactor (PBELAB) was proposed as an alternative treatment system for wastewater containing ammonia and nitrate compounds. The 60L PBELAB consisted of aeration and non-aeration zones, both of which were packed with plastic bioballs to enhance the surface area for the attachment of bacteria. The system was able to achieve complete removal of all nitrogen com...

The effect of different root zone temperatures on the concentration and content of B and Al in potato plants was examined using four different treatments of plastic mulches: T1: transparent polyethylene; T2: white polyethylene; T3: coextruded black and white polyethylene; T4: black polyethylene. An open-air treatment (T0) was used as control. The results showed significantly positive effects of...

CRACKS in ductile single crystals are analyzed here for geometries and orientations such that twodimensional states of anti-plane shear constitute possible deformation fields. The crystals are modelled as ideally plastic and yield according to critical resolved shear stresses on their slip systems. Restrictions on the asymptotic forms of stress and deformation fields at crack tips are establish...

An empirical method of non-destructive testing of a material was developed using pulse transmission by acoustic emission transducers to determine plastic deformation of 304 stainless steel specimens. This was done by means of comparison of pulse signals detected in an undeformed section with the pulse signals detected after passing through the deformation zone in the specimens. The pulse signal...

[1] We extend an elastodynamic finite element method to incorporate off-fault plastic yielding into a dynamic earthquake rupture model. We simulate rupture for models of faults with a kink (a sharp change in fault strike), examining how off-fault plastic yielding affects rupture propagation, seismic radiation, and near-fault strain distribution. We find that high-frequency radiation from a kink...

the objective of this study was to develop a numerical model for the prediction of temperature distribution, effective plastic strain distribution, and especially material flow in friction stir welding of copper plates. the deform-3d software was used by incorporating a lagrangian incremental formulation. threedimensional results of the material flow pattern which were extracted using the point...

Global plastic production has exceeded 300 million tons per year (Plastics Europe, 2015). In the marine and freshwater environments, larger plastics abrade and photo-degrade resulting in persistent environmental microplastics that are not effectively removed by existing wastewater treatment plants (WWTPs). The ecological effects of microplastics on the marine environment are poorly understood, ...