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The establishment of a data base of trace element analysis results obtained by neutron activation analysis of 183 marble samples, each weighing about 200 mg, from eight different quarrying localities for use in provenance studies is described and a summary of the results presented. The problems of sampling museum artefacts are discussed, and details of tests of the reproducibility of the technique are given together with those obtained from multiple-samples from single museum objects. Replicate analyses of a marble standard are also discussed. Thus these data are a measure of the accuracy and precision of the technique, as well as allowing an assessment of the variation in trace element composition within quarry sources and single blocks of marble, as used for artefacts.  相似文献   
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This paper looks at the relationship between the discourses of racism and sexism and the configuration of school space in an Australian high school. I argue that school space is proliferative of racialised and sexualised divisions. Divisions can be identified between groups of 'Asian' girls, between 'Asian' girls and 'Asian' boys, and between 'Asian' students and 'non-Asian' students. While these divisions are legislated by discourses of racism and sexism, this paper focuses attention on 'Asian' girls response to this situation. I argue that against the experience of social marginality 'Asian' girls tactically reproduce differences. By highlighting the changing dynamics of spatial-social divisions in school, I show how 'Asian' girls contest and rework racialising/sexualising discourses to recompose 'Asian'/femininity.  相似文献   
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Petrography, Eh‐pH calculations and the stable isotope composition of oxygen are used to interpret geochemical processes that occurred during iron oxide mineralization and dolomitization along the Menuha Ridge segment of the Paran Fault, southern Israel, adjacent to the Dead Sea Transform (DST). Iron mineralization is strongly localized in the fault zone as ferruginous lenses, whereas Fe dolomitization spreads laterally into the Cenomanian‐Turonian carbonate host rock as stratabound beds. The average oxygen isotope fractionation between syngenetic quartz and iron oxides in the ferruginous lenses gives a temperature of 50 ± 10°C and δ18O SMOW water = ?3.5‰; consistent with an origin from metalliferous groundwater flow in the sedimentary basin. Ferroan dolomite initially formed under strongly reducing conditions, but this was followed by oxidation and pseudomorphic replacement of the dolomite by a mesh of fine‐grained iron oxides (simple zoned dolomites). This cycle of ferroan dolomite formation and replacement by iron oxides was repeated in complex zoned dolomites. Dolomite oxygen isotope compositions fall into two groups: a high δ18O group corresponding to the simple zoned dolomites and non‐ferroan dolomites and a low δ18O group corresponding to the complex zoned dolomites. Water‐rock calculations suggest that the epignetic dolomites formed under fluid‐buffered conditions: the high δ18O group are indicated to have formed at temperatures of ca. 25°C for waters with δ18O = ?4 to 0‰; the low δ18O complex zoned dolomites at 50–75°C for waters with the same isotopic composition. A kinetic calculation for a complex zoned dolomite‐bearing bed indicates that dolomitization must have occurred at high values of the dolomite saturation index. This requirement for high Mg supersaturation and the indication that epigenetic dolomitization is more protracted in stratigraphically deeper formations located closer to the DST is consistent with models proposing that Mg‐rich solutions originated in the Dead Sea Rift.  相似文献   
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Neutron activation analyses of the body fabric of celadons from the main production sites of the Koryǒ period have shown differences in composition between kilns. Comparison of over 50 celadon objects in the collections of the British Museum with this data base from the production sites has permitted the assignment of over 40 of the pieces to their kiln of origin The majority show the trace element pattern of the Sadangri kilns, a smaller proportion are assigned to Yuchǒnri, while others are assigned to the kilns at Chinsanri (underglaze iron) and Kyǒngsǒ-dong (unglazed). A representative group of Chinese Yue wares arc clearly different from Koryǒ celadons in trace element composition.  相似文献   
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During 1993, the London-Bahrain Archaeological Expedition conducted a fourth season of excavations at the early second millennium settlement of Saar, Bahrain. A lower level of the temple was cleared, and a range of buildings to its north-west discovered. A new street was found opposite the temple entrance, and several of the buildings along the main street were further investigated. Further environmental research included a new programme of micromorphology and the start of research into the fish remains.  相似文献   
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