https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24427 Tue 30 Aug 2022 15:15:18 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31393 Tue 28 Jan 2020 16:23:14 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40851 Tue 19 Jul 2022 11:43:17 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39233 3A) is the most reactive component of the Portland cement and its hydration has an important impact on the workability and early strength of concrete. Recently, nanomaterials such as nano-silica (nano-SiO₂) have attracted much attention in cement-based materials because of its pozzolanic reactivity and the pore-filling effect. However, its influence on the hydration of C₃A needs to be well understood. In this study, the hydration kinetics of C₃A mixed with different percentages of nano-SiO₂ were studied and compared with pure C₃A. The hydration products were examined by different characterization techniques including XRD, XPS, and NMR spectroscopy and isothermal calorimetry analyses. The XRD results showed that the addition of nano-SiO₂ promoted the conversion of the intermediate product C₄AH₁₃. The isothermal calorimetry results showed that the addition of nano-SiO₂ significantly reduced the hydration exotherm rate of C₃A from 0.34 to less than 0.1 mW/g. With the presence of nano-SiO₂, the peaks for Q¹ were observed in ²⁹Si MAS-NMR measurements, and the content of Q¹ increased from 6.74% to 30.6% when the nano-SiO₂ content increased from 2 wt.% to 8 wt.%, whereas the proportion of Q⁴ gradually decreased from 89.1% to 63.6%. These results indicated a pozzolanic reaction provoked by the nano-SiO₂ combined with aluminate structures generating C-A-S-H gel.]]> Thu 28 Jul 2022 09:20:43 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42080 Thu 18 Aug 2022 11:12:17 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38815 Thu 06 Jul 2023 15:37:26 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:25538 Sat 24 Mar 2018 07:26:03 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45428 29Si NMR measurements. The SEM and MIP results demonstrated that CNTs acted as nano-filler in the composite and reduced the porosity of the matrix up to 14.16%. Based on these findings, it can be suggested that CNTs reinforced the AAS composite primarily by means of their physical effects.]]> Fri 28 Oct 2022 11:48:29 AEDT ]]>