University of South Australia

About: University of South Australia is a education organization based out in Adelaide, South Australia, Australia. It is known for research contribution in the topics: Population & Context (language use). The organization has 10086 authors who have published 32587 publications receiving 913683 citations. The organization is also known as: The University of South Australia & UniSA.

Covalently bonded interfaces for polymer/graphene composites

Abstract: The interface is well known for taking a critical role in the determination of the functional and mechanical properties of polymer composites. Previous interface research has focused on utilising reduced graphene oxide that is limited by a low structural integrity, which means a high fraction is needed to produce electrically conductive composites. By using 4,4′-diaminophenylsulfone, we in this study chemically modified high-structural integrity graphene platelets (GnPs) of 2–4 nm in thickness, covalently bonded GnPs with an epoxy matrix, and investigated the morphology and functional and mechanical performance of these composites. This covalently bonded interface prevented GnPs stacking in the matrix. In comparison with unmodified composites showing no reduction in electrical volume resistivity, the interface-modified composite at 0.489 vol% GnPs demonstrates an eight-order reduction in the resistivity, a 47.7% further improvement in modulus and 84.6% in fracture energy release rate. Comparison of GnPs with clay and multi-walled carbon nanotubes shows that our GnPs are more advantageous in terms of performance and cost. This study provides a novel method for developing interface-tuned polymer/graphene composites.

US teachers' and school counsellors' strategies for handling school bullying incidents

Abstract: A sample of 735 US teachers and school counsellors completed an online survey asking how likely they would be to use various strategies to respond to a hypothetical bullying incident. Analyses examined their use of five strategies: Ignoring the incident, Working with the bully, Working with the victim, Enlisting other adults, and Disciplining the bully. Differences in mean scores based on these strategies were found by gender of participant, the presence or absence of school anti‐bullying policies and programmes, and previous anti‐bullying training. Teachers and school counsellors differed on four of the five scale scores. Qualitative comment data add to the findings. Implications of the findings are discussed.

Kinetics and thermodynamics of sorption of nitroaromatic compounds to as-grown and oxidized multiwalled carbon nanotubes

Abstract: The sorption kinetics and thermodynamics of 1,3-dinitrobenzene (DNB), m-nitrotoluene (mNT), p-nitrophenol (pNP), and nitrobenzene (NB) on as-grown and nitric acid-oxidized multiwalled carbon nanotubes (MWCNTs) were investigated. The sorption kinetics was well described by a pseudo-second-order rate model, while both Langmuir and Freundlich models described the sorption isotherms well and the sorption thermodynamic parameters of equilibrium constant (K(0)), standard free energy (DeltaG), standard enthalpy (DeltaH), and standard entropy changes (DeltaS) were measured. The values of DeltaH and DeltaG suggested that the sorption of nitroaromatics (NACs) onto MWCNTs was exothermic and spontaneous. The structure, number, and position of nitro groups of NACs were the main factors affecting the sorption rate and capacity. Treatment of the MWCNTs with nitric acid increased both the surface area and the pore volume and introduced oxygen-containing functional groups to the MWCNTs, which depressed the sorption of NACs onto MWCNTs.