5 research outputs found

    A Technological and Typological Analysis of Lithic Material from Skovmosen I, Denmark

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     During road construction work, material attributed to the Final Palaeolithic was discovered at Skovmosen I, near Kongens Lyngby on Zealand, eastern Denmark. Although it is regularly mentioned in reviews of the southern Scandinavian Final Palaeolithic, the Skovmosen I assemblage has hitherto remained poorly described. We here review the site’s discovery history and its context. Aided by a three-dimensional digital recording protocol, this article details the assemblage composition and its technology. The assemblage is comprised of tanged points, scrapers and burins, alongside blades and cores as primary reduction products. Although evidently disturbed by the road construction that led to the site’s discovery, the material likely reflects the remains of a small Final Palaeolithic locale, where diverse activities were carried out

    Mesoporous and Graphitic Carbide-Derived Carbons as Selective and Stable Catalysts for the Dehydrogenation Reaction

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    Dehydrogenation of ethylbenzene to styrene is one of the most important catalytic processes in chemical industry. While it was demonstrated that nanocarbons like nanotubes, nanodiamond, or nanographite show high performance, especially selectivity, these powders give rise to handling problems, high pressure drop, hampered heat and mass transfer, and unclear health risks. More common macroscopic carbon materials like activated carbons show unsatisfying selectivity below 80%. In this study, mesoporous, graphitic, and easy to handle carbon powders were synthesized on the basis of the reactive extraction of titanium carbide in a novel temperature regime. This resulted in extraordinary properties like a mean pore diameter of up to 8 nm, pore volumes of up to 0.90 mL g<sup>–1</sup>, and graphite crystallite sizes exceeding 25 nm. Exceptional styrene selectivities of up to 95% were observed for materials synthesized above 1300 °C and pretreated with nitric acid. Furthermore, the long-term stability of these non-nanocarbon catalysts could be demonstrated for the first time during 120 h of time-on-stream
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