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81.
QUANTITATIVE ANALYSIS OF COPPER-TIN BRONZES BY MEANS OF GLOW DISCHARGE OPTICAL EMISSION SPECTROMETRY
Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed. 相似文献
82.
Jean-Marc Drouin Patrick Gautier Dalché Fabien Chareix Charles Lenay Monique Cottret Bernard Vandewalle François Laplanche Françoise Waquet Agnès Spiquel Ariane Poulantzas Olivier Martin Sophie Roux Ilana Löwy Françoise Waquet Isabelle Brian Michel Cassan Jean-Marc Rohrbasser Jean-Michel Vienne Marc Renneville Bernard Lahire Mikhaäl Xifaras Bertrand Binoche Stéphane Haber Jean-François Pradeau Noël Bonneuil Marie Jaisson 《Revue de synthèse / Centre international de synthèse》1997,118(4):551-613
83.
David L. Wykes 《The Journal of religious history》1997,21(2):178-192
The 1689 Toleration Act allowed Protestant dissenters freedom to worship in public, but it was only a limited toleration and dissenters continued to suffer discrimination. This article examines the experience of Quakers in one important area, the Anglican monopoly in teaching. Although the prosecution of unlicensed teachers was patchy, localised, and dependent upon the hostility and zeal of particular individuals, few dissenters escaped harassment. Moreover, Friends appear to have suffered more severely because of the particular dislike that they still provoked and their unwillingness to compromise which often led to imprisonment. The growth in High Church feeling during Anne's reign led to a more rigorous enforcement of the existing statutes and the passing of the Schism Act (1714). The consequences of an Anglican educational monopoly have not been properly considered by historians largely from the assumption that the Schism Act was fatally compromised by the death of Queen Anne, and because little attention has been paid to the continued harassment of dissenters after toleration who attempted to teach. The Schism Act was repealed in 1719, but freedom for Quakers and other dissenters to teach had already been achieved largely through the courts. 相似文献
84.
The transformation of the Indus Civilization 总被引:1,自引:0,他引:1
Gregory L. Possehl 《Journal of World Prehistory》1997,11(4):425-472
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ABSTRACT. Real variable analysis has een used to great benefit in a variety of classical problems in location theory. In this paper we explore basic complex variable techniques in one formulation of the obnoxious location problem. A general definition of center points is first given and used to formulate several alternate versions of the obnoxious location problem. A logarithmic transformation is then used to demonstrate some equivalences between these families of distinct location problems (defined via center points). A prototype logarithmic potential function which results from this formulation is then investigated, and it is demonstrated that the extremal solutions with this objective reside on the boundary of its domain of definition. An application using zero- and one-dimensional centers is discussed, and a generalization to the spatial obnoxious problem is also briefly examined. We define a zero-dimensional center as a critical point of the logarithmic potential function, and it is shown that these centers are equivalent to the solutions of the Complex Moment Problem. 相似文献
87.
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89.
Candice L. Goucher 《African Archaeological Review》1993,11(1):197-215
This paper examines the history of African metallurgy in the era of Atlantic trade. It reports on excavations at the John Reeder foundry site in St Thomas, Jamaica. The transfer of African technologies to the Caribbean reveals the plantation economy's dependence on African technical expertise, not merely slave labour. The comprehensive focus on the Atlantic world also informs archaeological investigations of African-European interaction in West Central Africa. The complexity of Atlantic technological history is characterized by a diverse range of dynamic interactions, rather than the inevitable decline of Africanderived systems. Only by identifying processes as well as products of African technological interaction will it be possible fully to reconstruct the forging of the African past.
Résumé Cet article examine l'histoire de la métallurgie africaine à l'ère du commerce atlantique. Il rend compte des excavations au site de la fonderie John Reeder, à St Thomas, en Jamaïque. Le transfert des technologies africaines aux Antilles révèle à quel point l'économie de plantation dépendait de l'expertise technique africaine, et pas seulement de l'esclavage. L'accent placé sur le monde atlantique inspire aussi les recherches archéologiques sur l'interaction afro-européenne à l'ouest de l'Afrique centrale. La complexité de l'histoire technologique atlantique est caractérisée par une gamme diverse d'interactions dynamiques, plutôt que par l'inévitable déclin des systèmes africains dérivés. Ce n'est qu'en identifiant les processus aussi bien que les produits de l'interaction technologique africaine qu'il sera possible de reconstruire complètement l'élaboration du passé africain.相似文献
90.
Kevin D. Ingram Kenneth E. Daugherty James L. Marshall 《Journal of archaeological science》1993,20(6)
Several samples of pyramids from Giza were obtained. The samples were analysed by scanning electron microscopy, electron diffraction by X-rays, powder X-ray diffraction, inductively coupled plasmography, Fourier-transform infrared spectroscopy and other techniques. Some scientists who have recently studied the pyramids have suggested that the pyramids were poured into place, stone by stone. The prevailing theory among Egyptologists is, of course, that the pyramids were built from blocks of natural stone. All of the results obtained during this study directly support the concept that the pyramids are made of limestone and are not cementitious in nature. 相似文献