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Ray L. Frost

Bio: Ray L. Frost is an academic researcher from Queensland University of Technology. The author has contributed to research in topics: Raman spectroscopy & Infrared spectroscopy. The author has an hindex of 86, co-authored 1356 publications receiving 41053 citations. Previous affiliations of Ray L. Frost include University of Western Sydney & Southwest University of Science and Technology.


Papers
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TL;DR: In this article, the authors synthesize cobalt hydroxide, cobalt oxyhydroxide and cobalt oxide nanomaterials through simple soft chemistry, and characterisation of these cobalt-based materials is fully developed, including X-ray diffraction, transmission electron microscopy combined with selected area electron diffraction.
Abstract: Cobalt hydroxide, cobalt oxyhydroxide, and cobalt oxide nanomaterials were synthesized through simple soft chemistry. The cobalt hydroxide displays hexagonal morphology with clear edges 20 nm long. This morphology and nanosize is retained through to cobalt oxide Co3O4 through a topotactical relationship. Cobalt oxyhydroxide and cobalt oxide nanomaterials were synthesized through oxidation and low-temperature calcination from the as-prepared cobalt hydroxide. Characterization of these cobalt-based nanomaterials was fully developed, including X-ray diffraction, transmission electron microscopy combined with selected area electron diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and thermal gravimetric analysis. Bonding of the divalent cobalt hydroxide from the oxyhydroxide and oxides by studying their high-resolution XPS spectra for Co 2p3/2 and O 1s. Raman spectroscopy of the as-prepared Co(OH)2, CoO(OH), and Co3O4 nanomaterials characterized each material. T...

1,249 citations

Journal ArticleDOI
TL;DR: In this paper, the synthesis and absorbing properties of a wide variety of porous sorbent materials have been studied for application in the removal of organics, particularly in the area of oil spill cleanup.
Abstract: This paper reviews the synthesis and the absorbing properties of the wide variety of porous sorbent materials that have been studied for application in the removal of organics, particularly in the area of oil spill cleanup. The discussion is especially focused on hydrophobic silica aerogels, zeolites, organoclays and natural sorbents many of which have been demonstrated to exhibit (or show potential to exhibit) excellent oil absorption properties. The areas for further development of some of these materials are identified.

987 citations

Journal ArticleDOI
TL;DR: In this article, the difference in the local environment of CO32−, NO3−, SO42−, and ClO4− in Mg/Al-hydrotalcite compared to the free anions was studied by infrared and Raman spectroscopy.
Abstract: The difference in the local environment of CO32−, NO3−, SO42−, and ClO4− in Mg/Al-hydrotalcite compared to the free anions was studied by infrared and Raman spectroscopy. In comparison to free CO32− a shift toward lower wavenumbers was observed. A band around 3000–3200 cm−1 has been attributed to the bridging mode H2O-CO32−. The IR spectrum of CO3− hydrotalcite clearly shows the split ν3 band around 1365 and 1400 cm−1 together with weak ν2 and ν4 modes around 870 and 667 cm−1. The ν1 mode is activated and observed as a weak band around 1012 cm−1. The Raman spectrum shows a strong ν1 band at 1053 cm−1 plus weak ν3 and ν4 modes around 1403 and 695 cm−1. The symmetry of the carbonate anions is lowered from D 3 h to C 2 s resulting in activation of the IR inactive ν1 mode around 1050–1060 cm−1. In addition, the ν3 shows a splitting of 30–60 cm−1. Although NO3-hydrotalcite has incorporated some CO32− the IR shows a strong ν3 mode at 1360 cm−1 with a weak band at 827 cm−1, and the ν4 band is observed at 667 cm−1, although it is largely obscured by the hydrotalcite lattice modes. The Raman spectrum shows a strong ν1 mode at 1044 cm−1 with a weaker ν4 band at 712 cm−1. The ν3 mode at 1355 cm−1 is obscured by a broad band due to the presence of CO32−. The symmetry of NO3− did not change when incorporated in hydrotalcite. The IR spectrum of SO4-hydrotalcite shows a strong ν3 at 1126, ν4 at 614 and a weak ν1 mode at 981 cm−1. The Raman spectrum is characterized by a strong ν1 mode at 982 cm−1 plus medium ν2 and ν4 bands at 453 and 611 cm−1; ν3 cannot be identified as a separate band, although a broad band can be seen around 1134 cm−1. The site symmetry of SO42− is lowered from T d to C 2 v . The distortion of ClO4− in the interlayer of hydrotalcite is reflected in the IR spectrum with both ν3 and ν4 bands split around 1096 and 1145 cm−1 and 626 and 635 cm−1, respectively. A weak ν1 band is observed at 935 cm−1. The Raman spectrum shows a strong ν1 mode at 936 cm−1 plus ν2 and ν4 bands at 461 and 626 cm−1, respectively. A ν3 mode cannot be clearly recognized, but a broad band is visible around 1110 cm−1. These data indicative a lowering of symmetry from T d to C s .

457 citations

Journal ArticleDOI
15 Apr 2006
TL;DR: The chemical compositions based on the XPS survey scans were in good agreement with the expected composition and a distinction could be made between boehmite and pseudoboehmitebased on the slightly lower ratio of oxygen to hydroxyl groups and water in pseudobOEhmite.
Abstract: Synthetic corundum (Al2O3), gibbsite (Al(OH)3), bayerite (Al(OH)3), boehmite (AlO(OH)) and pseudoboehmite (AlO(OH)) have been studied by high resolution XPS. The chemical compositions based on the XPS survey scans were in good agreement with the expected composition. High resolution Al2p scans showed no significant changes in binding energy, with all values between 73.9 and 74.4 eV. Only bayerite showed two transitions, associated with the presence of amorphous material in the sample. More information about the chemical and crystallographic environment was obtained from the O1s high resolution spectra. Here a clear distinction could be made between oxygen in the crystal structure, hydroxyl groups and adsorbed water. Oxygen in the crystal structure was characterised by a binding energy of about 530.6 eV in all minerals. Hydroxyl groups, present either in the crystal structure or on the surface, exhibited binding energies around 531.9 eV, while water on the surface showed binding energies around 533.0 eV. A distinction could be made between boehmite and pseudoboehmite based on the slightly lower ratio of oxygen to hydroxyl groups and water in pseudoboehmite.

386 citations

Journal ArticleDOI
TL;DR: In this article, the FT-IR and FT-Raman spectroscopy were used to characterize synthetic Mg-, Ni- and Co-hydrotalcite, and they showed that the composition changes brought about by changing the divalent metal result in small but significant changes in band positions of the modes related to the hydroxyl groups.

333 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations

Journal ArticleDOI
TL;DR: Biesinger et al. as mentioned in this paper proposed a more consistent and effective approach to curve fitting based on a combination of standard spectra from quality reference samples, a survey of appropriate literature databases and/or a compilation of literature references and specific literature references where fitting procedures are available.

7,498 citations

Journal ArticleDOI
TL;DR: In this article, a detailed analysis of the thermal expansion mechanism of graphite oxide to produce functionalized graphene sheets is provided, where it is shown that the decomposition rate of the epoxy and hydroxyl sites exceeds the diffusion rate of evolved gases, yielding pressures that exceed the van der Waals forces holding the graphene sheets together.
Abstract: A detailed analysis of the thermal expansion mechanism of graphite oxide to produce functionalized graphene sheets is provided. Exfoliation takes place when the decomposition rate of the epoxy and hydroxyl sites of graphite oxide exceeds the diffusion rate of the evolved gases, thus yielding pressures that exceed the van der Waals forces holding the graphene sheets together. A comparison of the Arrhenius dependence of the reaction rate against the calculated diffusion coefficient based on Knudsen diffusion suggests a critical temperature of 550 °C which must be exceeded for exfoliation to occur. As a result of their wrinkled nature, the functionalized and defective graphene sheets do not collapse back to graphite oxide but are highly agglomerated. After dispersion by ultrasonication in appropriate solvents, statistical analysis by atomic force microscopy shows that 80% of the observed flakes are single sheets.

3,340 citations

Journal ArticleDOI
TL;DR: From a comprehensive literature review, it was found that some LCAs, in addition to having wide availability, have fast kinetics and appreciable adsorption capacities too.

3,163 citations