Publications by authors named "Caroline A Kirk"

The formation of different nickel and cobalt layered hydroxide phases by a variety of solution and solid-state synthesis methods has been investigated. Initially, preparative methods were refined to generate single-phase products from metal(II) nitrate hexahydrate starting materials which were then characterised by powder X-ray diffraction, vibrational spectroscopy and thermogravimetric analysis. As well as the brucite type β-M(OH) and the hydrotalcite-like [M(OH)(HO)] alpha-phases (where M = Ni, Co), two different hydroxynitrate phases were isolated with the generic formula M(OH)(NO) with = 0.

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Pollution by hexavalent chromium is a growing, global problem. Its presence in public water systems is often the result of industrial activities, both past and present. In this study, tricalcium aluminate (C3A, CaAlO) is added to solutions of varying concentrations of potassium chromate (KCrO) and samples of both the solid and liquid are taken at various time intervals to monitor the removal of chromium from the solutions.

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Metatorbernite [Cu(UO)(PO)·8HO] is a promising remediation material for environmental uranium contamination. Previous X-ray diffraction studies have been unable to definitively locate hydrogen positions within metatorbernite, which are key to determining the hydrogen-bond network that helps to stabilize the structure. Here, hydrogen positions have been determined using a combination of neutron powder diffraction and the computational modelling technique random structure searching (AIRSS).

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Aerosol-assisted chemical vapor deposition (AACVD) was used for the first time in the preparation of thin-film electrochromic nickel(II) oxide (NiO). The as-deposited films were cubic NiO, with an octahedral-like grain structure, and an optical band gap that decreased from 3.61 to 3.

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Two mechanisms of doping Li(3)NbO(4), which has an ordered, rock salt superstructure, have been established. In the "stoichiometric mechanism", the overall cation-to-anion ratio is maintained at 1:1 by means of the substitution 3Li(+) + Nb(5+) --> 4Ni(2+). In the "vacancy mechanism", Li(+) ion vacancies are created by means of the substitution 2Li(+) --> Ni(2+).

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