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Abstract. An automated Fourier Transform Spectroscopic (FTS) solar observatory was established in Darwin, Australia in August 2005. The laboratory is part of the Total Carbon Column Observing Network, and measures atmospheric column abundances of CO 2 and O 2 and other gases. Measured CO 2 columns were calibrated against integrated aircraft profiles obtained during the TWP-ICE campaign in JanuaryFebruary 2006, and show good agreement with calibrations for a similar instrument in Park Falls, Wisconsin. A clearsky low airmass relative precision of 0.1% is demonstrated in the CO 2 and O 2 retrieved column-averaged volume mixing ratios. The 1% negative bias in the FTS X CO 2 relative to the World Meteorological Organization (WMO) calibrated in situ scale is within the uncertainties of the NIR spectroscopy and analysis.

Structure and morphology play a critical role in determining the performance of organic photovoltaic devices. In this paper, variation of the postannealing cooling rate is used to create a series of “snapshots” of the vertical and interfacial reorganization processes that occur upon annealing. The data show that slower cooling rates result in significantly enhanced device efficiencies primarily driven by increased short circuit current and fill factor. UV−vis spectroscopy, X-ray diffraction (XRD), near-edge X-ray absorption fine structure spectroscopy (NEXAFS), atomic force microscopy (AFM), and contact angle measurements are used to probe the origin of these improvements. Our results show evidence for a distinct and changing vertical stratification and interfacial structure in the device throughout the annealing process, with both composition and crystallinity varying through the active layer. The implications of these changes are discussed in terms of device properties.

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A new method for the prediction of the viscosity of coal ash slags, in the Newtonian region, is presented. The technique is modeled on experimental viscosity data less than 1000 Pa s and hence is most reliable in that region. The capability of the model in predicting the viscosity of slags from coal ash was found to be superior to a number of the most commonly used empirical models found in the literature, which are based on simplified oxide melts or British coal ash slags. The method also provides an indication of the relative fluxing strength of the basic oxides usually found in coal ash slags. It was found that the fluxing strength is related to the inverse of the cation radius.

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A 63-90 µm size fraction of an Australian bituminous coal sample was fed into a drop tube furnace (DTF) and a pressurized drop tube furnace (PDTF) to generate chars. A gas temperature of 1573 K and system pressures of 0.1, 0.5, 1.0, and 1.5 MPa were considered. Particle size analysis, scanning electron microscopy (SEM), and image analysis were employed to analyze the chars produced in order to investigate the effect of system pressure on the resultant char structure and morphology. The char character was found to be influenced significantly by the system pressure. Results obtained indicated that the coal and char fragmentation might have occurred during devolatilization at high pressure. The char size (as characterized by the swelling ratio) was also observed to increase with system pressure. The cross-sectional characterization of the char particles indicated that at high pressure the majority of the char particles are of high porosity with thin walls or network (the group I type) rather than of medium porosity with thicker walls or network (the group II type) and of low porosity (the group III type). Char particles generated at high pressure were also observed to have a higher internal and surface porosity.

A range of pulverized coals were combusted in a laboratory drop-tube furnace at temperatures of 1573, 1723, and 1873 K under oxidizing and reducing conditions to determine the effect of combustion stoichiometry on ash formation mechanisms. As iron mineral transformations were expected to be most affected by combustion stoichiometry, two of the test coals chosen were of high pyrite (FeS2) content and two of high siderite (FeCO3) content. It was found that the ash formation mechanisms of excluded quartz, koalinite, and calcite were not affected by oxidizing or reducing combustion conditions. Excluded pyrite was found to decompose to pyrrhotite, which oxidized to produce an FeO−FeS melt phase which was stable under reducing conditions. Under oxidizing conditions oxidation continued, producing magnetite and hematite. Excluded siderite was found to decompose to wustite, which was stable under reducing conditions, but oxidized to produce magnetite under oxidizing conditions. Included pyrite and siderite were determined to behave as for excluded pyrite and siderite if there was no contact with alumino-silicates. Included pyrite that contacted alumino-silicate minerals was observed to form two-phase FeS/Fe-glass ash particles, with incorporation of iron into the glass proceeding as the FeS phase was oxidized. Included siderite that contacted alumino-silicate minerals was determined to directly form iron alumino-silicate glass ash particles. Iron alumino-silicate glass ash was determined to form with iron in the Fe2+ state, much of which subsequently transformed to the Fe3+ state in oxidizing conditions, but remained primarily as in the Fe2+ state under reducing conditions.