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51.
Publication patterns of NBS, USGS and CCRMP reference materials data are traced over the past 35 years by literature source, analytical methods employed, and constituents measured.  相似文献   
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What lay behind the decision to reclassify Pluto as a "dwarf planet" at August's IAU General Assembly in Prague?  相似文献   
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Nine rare earth elements have been determined by inductively coupled plasma spectrometry (ICP) in eight USGS reference samples, MAG-1, SCo-1, SDC-1, BIR-1, DNC-1, W-2, BCR-1 and BHVO-1 and in the ANRT Glauconite, GL-O. Along with these new data, updated compilations are presented for these samples. Good agreement is observed between the present work and the compiled values.  相似文献   
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Using high-resolution, low-scan-rate, all-sky CCD cameras and high-level CCD video cameras, the SPanish Meteor and fireball Network (SPMN) recorded the 2007 κ Cygnid fireball outburst from several observing stations. Here, accurate trajectory, radiant and orbital data obtained for the κ Cygnid meteor are presented. The typical astrometric uncertainty is 1–2 arcmin, while velocity determination errors are of the order of 0.3–0.6 km s−1, though this depends on the distance of each event to the station and its particular viewing geometry. The observed orbital differences among 1993 and 2007 outbursts support the hypothesis that the formation of this meteoroid stream is a consequence of the fragmentation of a comet nucleus. Such disruptive process proceed as a cascade, where the break up of the progenitor body leads to produce small remnants, some fully disintegrate into different clumps of particles and other remaining as dormant objects such as 2008ED69, 2001MG1 and 2004LA12 which are now observed as near-Earth asteroids. In addition to the orbital data, we present a unique spectrum of a bright  κ  Cygnid fireball revealing that the main rocky components have chondritic abundances, and estimations of the tensile strength of those fireballs that exhibited a catastrophic disruption behaviour. All this evidence of the structure and composition of the κ Cygnid meteoroids is consistent with being composed by fine-grained materials typically released from comets.  相似文献   
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This is the seventeenth survey in the series of Geochemical Reference Sample (GRS) Bibliography published in Geostandards Newsletter and is designated as Part XVII in the series. Part XVII contains references extracted from major analytical chemistry and geochemistry journals that have become available to the author between January and December 1996. A few earlier ones which were not available at the time of the previous report (Part XVI), together with those which were inadvertently overlooked, have also been included.  相似文献   
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Two major monzonoritic dykes occur in the Egersund-Ogna anorthositic massif (S.W. Norway): the Lomland dyke, which varies from norite to monzonite, and the Vettaland ferronoritic dyke. They are characterized by high Fe, Ti and P contents, low SiO2, variable K2O (0.5%–4.5%) and high Fe/Mg ratios. Small variations in REE distribution are observed inside the Lomland dyke [La/Yb=12; LREE ca. 150–180 (chondrite-normalized values), neutral to slightly positive Eu anomaly]. Part of the Vettaland dyke is severely depleted in Zr, Rb and REE and shows a positive Eu anomaly. All rocks are depleted in U and Th, and show very low Cr and Ni contents, as well as high Sr contents (400–600 ppm). Variation within the Lomland dyke is satisfactorily ex-plained through subtraction of an apatite-bearing noritic cumulate. The role of apatite is predominant in controlling the REE behaviour. Eutectic partial melting of a Fe-rich noritic cumulate (containing apatite) under low pH2O conditions is suggested for the Vettaland dyke by REE modelling. Sr isotopic initial ratios are different in Lomland (ca. 0.708) and Vettaland (ca. 0.706) dykes. These values preclude direct derivation from the mantle as well as comagmatic relationship with anorthosite. Contamination of a mantle derived magma by deep crustal material or anatexis of the LIL depleted lower crust is compatible with the low U and Th contents, and with the Pb isotopic ratios. The Vettaland partial melting process is extended to all monzonoritic types, the necessary heat being provided by the high temperature anorthositic crystal mush. Chargé de Recherches du F.N.R.S (Belgium)  相似文献   
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