https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36405 Wed 24 May 2023 09:45:52 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:23079 Wed 11 Apr 2018 09:21:28 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:49071 Wed 03 May 2023 16:08:05 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:54534 Tue 27 Feb 2024 20:42:12 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:50414 2CO₃: 43.5%, Na₂CO₃: 31.5%, K₂CO₃: 25%) during slow temperature ramping rates (5 °C/min) under N₂ at temperatures above 750 °C. Initial findings suggest that approximately 50 wt% of graphite experiences interlayer expansion. The conventional d spacing of 0.34 nm is modified to a range of intervals between 0.41 nm and 1.22 nm. As a consequence of high operational temperature (800 °C), cations (Li⁺, Na⁺ and K⁺) as well as potentially the anion (CO₃²–) intercalate between graphitic layers and overcome Van der Waal force between layers. Employing a pressurized N₂ environment of 5 bar and 10 bar successfully controls carbonate vaporization and decomposition, as well as inducing ordered layer manipulation to exfoliate more graphite planes from the edges towards deeper levels of the particles. Exploring parameters of both carbonate loading and treatment time in addition to pressure demonstrate that this work opens up a rich selection of parameters that can be used to produce carbons with tuned properties from graphite.]]> Tue 25 Jul 2023 17:58:35 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:52767 Tue 14 Nov 2023 15:12:48 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:20725 Sat 24 Mar 2018 08:00:20 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:24734 3+ intermediate is a key feature of this electrodeposition mechanism, the formation of which is dependent on the substrate, which in this case is either platinum, MnO₂ or MnOOH. On the platinum surface, for all electrolytes, soluble Mn³⁺ is produced initially. The stability of this soluble Mn³⁺ species determines the initial morphology, and rate of change of mechanism for the process. In a neutral electrolyte, nucleation and growth of MnO₂ occurs primarily through the precipitation of a 2D film of MnOOH on the platinum, which rapidly covers the surface. Nucleation in an acidic H₂SO₄ system occurs primarily via a disproportionation route which forms 3D MnO₂ hemispheroids that cover the substrate slowly. Subsequent growth of MnO₂ in both electrolytes then proceeds via formation of a MnOOH film, which is subsequently oxidized in the solid state to form MnO₂. MnOOH oxidation to MnO₂ appears kinetically limited, which is overall a limiting factor in the electrodeposition process.]]> Sat 24 Mar 2018 07:10:58 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:45721 Mon 29 Jan 2024 18:37:58 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:45397 Mon 29 Jan 2024 18:34:23 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40921 Mon 29 Jan 2024 17:48:04 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:44056 2CO₃: 43.5%, Na₂CO₃: 31.5%, K₂CO₃: 25% mol), subjected to two different higher heating temperatures (350 °C and 600 °C). It is shown here that the addition of a carbonate eutectic affects char-making reactions through: tar generation modification, changes in the emitted volatile molecules, alteration of surface oxygenate bonds as well as transformation in the morphology of the remnant char. Initial results using Differential Thermal Gravimetric Analysis (DTG) show that, in carbonate treated samples, char yield is increased at both temperatures investigated. In treated cellulose, a reduced temperature onset of mass loss is observed, expected to be from modified depolymerisation and inhibition of levoglucosan formation for samples heated to both 350 °C and 600 °C. Gas analysis by micro-GC proves that carbonate is involved in the cracking of condensable volatiles, which generates a highly porous char structure and increases the emission of non-condensable volatiles. In addition, SEM results for carbonate treated cellulose demonstrate extensive pore generation including both surface and internally generated pores and interconnected tunnel-like structures at higher temperature (600 °C). This was not reflected however in BET results due to the melted salt blocking the available internal porous structure. Improvement in BET results for chars produced at 600 °C was regardless seen on carbonate addition in both biomass (improving from 371 m² g⁻¹ to 516 m² g⁻¹) and lignin (improving from 11 m² g⁻¹ to 209 m² g⁻¹).]]> Mon 29 Jan 2024 17:46:29 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:54847 Fri 15 Mar 2024 17:00:44 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46145 Eucalyptus pilularis biomass and ternary molten carbonate eutectic [Li₂CO₃, 43.5%; Na₂CO₃, 31.5%; and K₂CO₃, 25% (mole percentage)] in thermogravimetric analysis at three different temperatures, 600, 750, and 900 °C, was studied. These salts affect the slow pyrolysis process, including changes in the volatile release mechanism and the morphology of remnant char material. The initial results show that, in the presence of molten carbonate, biomass particles make bubble-shaped larger particles, which result in less volatile emissions and more char residue. It is suggested that the ternary eutectic has a chemical diluent and catalytic role, particularly in the case of higher salt doping. Results from scanning electron microscopy images give strong evidence that molten carbonates capture volatiles inside swelling carbon particles, which causes the generation of various sizes of pores as well as char-making reactions, and at a higher temperature, the bubble-shaped particles will rupture. Swelling of this nature has previously only been observed clearly in coal precursors; however, this is the first observation in a biomass-based system. Also, at a temperature above 750 °C, decomposition of molten carbonate generates CO₂ and carbon/carbonate gasification produces CO as well as a more “activated” biochar.]]> Fri 11 Nov 2022 18:31:02 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:54173 Fri 09 Feb 2024 14:23:24 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40340 Fri 08 Jul 2022 10:26:31 AEST ]]>