Publications by authors named "J A Zasadzinski"

Article Synopsis
  • Extrusion welding of AlMgSi(Cu) alloys using porthole dies creates hollow shapes with seam welds, but improper alloy composition or conditions can weaken the weld's strength compared to the base material.
  • Predictive modeling of welding conditions based on alloy composition, temperature, and pressures streamlines porthole die design, reducing necessary testing and production costs.
  • Laboratory tests on two AlMgSi(Cu) alloy compositions showed that optimal welding at 550°C and 350 MPa resulted in significant weld strength, with the highest relative weld strength recorded at 87% for one alloy.
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Before artificial ageing, extruded aluminium profiles are subjected to stretching with a small cold deformation in the range of 0.5-2%. This deformation improves the geometrical stability of the extruded product and causes changes in the microstructure of the profile, which leads to the strain hardening of the material after artificial ageing.

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Hypothesis: Lysopalmitoylphosphatidylcholine (LysoPC) is a soluble single-chain surfactant product of the innate immune system degradation of double-chain phospholipids. LysoPC adsorption to the air-water interface in lung alveoli can be modeled using alveolar-sized bubbles of constant surface area in a capillary pressure microtensiometer to show that adsorption is diffusion limited both below and above the critical micelle concentration (CMC). Above the CMC, a local equilibrium model is proposed in which depletion of the local monomer concentration drives dissociation of micelles in a region near the bubble surface.

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Improving the qubit's lifetime (T) is crucial for fault-tolerant quantum computing. Recent advancements have shown that replacing niobium (Nb) with tantalum (Ta) as the base metal significantly increases T, likely due to a less lossy native surface oxide. However, understanding the formation mechanism and nature of both surface oxides is still limited.

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