Effects of UV Stabilizers on Polypropylene Outdoors (open access)

Effects of UV Stabilizers on Polypropylene Outdoors

This article looks at hindered amine light stabilizers (HALSs) and nano ZnO were used to stabilize polypropylene (PP) film-based formulations that were exposed to ultraviolet (UV) light for different lengths of time, simulating the harsh outdoor weather of Dallas, Texas, USA. UV doses applied in our laboratory are 121 times larger than the UV dose provided by the sunlight in Texas. 15 different compositions were studied. The combination of HALSs and nano-ZnO stabilizers makes the PP films harder—which is important for some PP applications, such as toy manufacturing.
Date: April 1, 2020
Creator: Brostow, Witold, 1934-; Lu, Xinyao; Gencel, Osman & Osmanson, Allison T.
System: The UNT Digital Library
Dynamic Shear Deformation of a Precipitation Hardened Al0.7CoCrFeNi Eutectic High-Entropy Alloy Using Hat-Shaped Specimen Geometry (open access)

Dynamic Shear Deformation of a Precipitation Hardened Al0.7CoCrFeNi Eutectic High-Entropy Alloy Using Hat-Shaped Specimen Geometry

The article reports on the shear deformation of a eutectic structured HEA and effect of precipitation on shear deformation, particularly Al₀.₇CoCrFeNi high-entropy alloy (HEA). A split-Hopkinson pressure bar (SHPB) was used to compress the hat-shaped specimens to study the local dynamic shear response of the alloy. The change in the width of shear bands with respect to precipitation and deformation rates was studied. The precipitation of L1₂ phase did not delay the formation of adiabatic shear bands (ASB) or affect the ASB width significantly, however, the deformed region around ASB, consisting of high density of twins in fcc phase, was reduced from 80 µm to 20 µm in the stronger precipitation strengthened condition.
Date: April 10, 2020
Creator: Gwalani, Bharat; Wang, Tianhao; Jagetia, Abhinav; Gangireddy, Sindhura; Muskeri, Saideep; Mukherjee, Sundeep et al.
System: The UNT Digital Library
Triplet photosensitizer-nanotube conjugates: synthesis, characterization and photochemistry of charge stabilizing, palladium porphyrin/carbon nanotube conjugates (open access)

Triplet photosensitizer-nanotube conjugates: synthesis, characterization and photochemistry of charge stabilizing, palladium porphyrin/carbon nanotube conjugates

Author Manuscript version of an article investigating the ability of a triplet photosensitizer to generate long-lived charge separated states, in contrast to traditionally used singlet photosensitizers, in covalently functionalized single-walled carbon nanotube hybrids.
Date: April 21, 2020
Creator: Arellano, Luis M.; Gobeze, Habtom B.; Gómez-Escalonilla, María J.; Fierro, Jose Luis G.; D'Souza, Francis & Langa, Fernando
System: The UNT Digital Library