We propose to form nanoelectrode arrays by deposition of the electrocatalyst through lyotropic liquid crystalline templates onto inert electrode support. Whereas Prussian Blue is known to be a superior electrocatalyst in hydrogen peroxide reduction, carbon materials used as electrode support demonstrate only a minor activity. We report on the possibility for nanostructuring of Prussian Blue by its electrochemical deposition through lyotropic liquid crystalline templates, which is noticed from atomic force microscopy images of the resulting surfaces. The resulting Prussian Blue based nanoelectrode arrays in flow injection analysis mode demonstrate a sub-part-per-billion detection limit (1 x 10(-)(8) M) and a linear calibration range starting exactly from the detection limit and extending over 6 orders of magnitude of H(2)O(2) concentrations (1 x 10(-)(8) to 1 x 10(-)(2) M), which are the most advantageous analytical performances in hydrogen peroxide electroanalysis.

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Waikato samples were pre-treated following standard AMS protocols (UCI KCCAMS, 2011a, b). Following pre-treatment, charcoal (∼2 mm fragments) samples were converted to CO2 in sealed quartz tubes by oxidation at 800°C, using pre-baked CuO in the presence of silver wire to absorb any SOx and NOx produced. Shell (< 3 mm fragments, 35-45 mg) were etched in 0.1M HCl at 80°C to remove ∼45% of the surface. Cleaned shells were then tested for recrystallization by Feigl staining (Friedman, 1959) to ensure either aragonite, or a natural aragonite/calcite distribution was present in the shell (e.g. Nerita sp.). CO2 was collected from shells by reaction with 85% H3PO4. Cryogenically separated CO2 was then reduced to graphite with H2 at 550°C using an iron catalyst. δ 13 C was measured either on a LGR Isotope analyser CCIA-46EP or a Thermos Scientific MAT252 IRMS. Pressed graphite was analysed at the Keck Radiocarbon Dating Laboratory, University of California on a NEC 0.5MV 1.5SDH-2 AMS system (Southon et al., 2004). At ANSTO, after visual inspection for the presence of any powdery, potentially extraneous, calcite deposition shell surfaces were physically cleaned by abrasion of 10-25% of thickness with a Dremel ® tool followed by chemical etching of another 10% with 0.5M HCl for 1-5 minutes under sonication at room temperature (Hua et al., 2001). Feigl

Elucidating the material culture of early people in arid Australia and the nature of their environmental interactions is essential for understanding the adaptability of populations and the potential causes of megafaunal extinctions 50-40 thousand years ago (ka). Humans colonized the continent by 50 ka, but an apparent lack of cultural innovations compared to people in Europe and Africa has been deemed a barrier to early settlement in the extensive arid zone. Here we present evidence from Warratyi rock shelter in the southern interior that shows that humans occupied arid Australia by around 49 ka, 10 thousand years (kyr) earlier than previously reported. The site preserves the only reliably dated, stratified evidence of extinct Australian megafauna, including the giant marsupial Diprotodon optatum, alongside artefacts more than 46 kyr old. We also report on the earliest-known use of ochre in Australia and Southeast Asia (at or before 49-46 ka), gypsum pigment (40-33 ka), bone tools (40-38 ka), hafted tools (38-35 ka), and backed artefacts (30-24 ka), each up to 10 kyr older than any other known occurrence. Thus, our evidence shows that people not only settled in the arid interior within a few millennia of entering the continent, but also developed key technologies much earlier than previously recorded for Australia and Southeast Asia.

A summary of 14C data from atmospheric sampling and measurements on wood from annual tree rings for the period 1945-1997 AD is presented and evaluated. Atmospheric records are characterized by different distributions of bomb-test 14C between the Northem and Southem Hemispheres, latitude dependence, and seasonal fluctuations. Radiocarbon data from tree rings are summarised and plotted against atmospheric records from similar latitudes. In some cases, discrepancies are found. Possible reasons for this include: 1) the use of stored carbohydrate from the previous year, 2) different 14C levels in the air around subcanopy trees due to respiration of CO2, 3) regional and local effects of anthropogenic CO2 and 14C sources, 4) sampling of wood material too close to ring boundaries, and 5) insufficient pretreatment of tree ring sampies for dating. But in cases where trees were carefully selected and the sampies adequately pretreated, radiocarbon data from tree rings show excellent agreement with direct atmospheric sampling records.

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We report results of a study examining controls on the degradation of chars produced at 300, 400 21 and 500˚C from radiocarbon-free wood, deployed for three years in a humid tropical rainforest soil 22 in north Queensland, Australia. The chars were subjected to four treatments (i) no litter (

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