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991.
The notion of the “secret cause”, which appears in many classical texts is tied to a particular practice of science and a conception of its methods where the “law” finds itself at the center of the nexus. If certain phenomena appear to escape the law, one is obliged to amend the law through the introduction of a series of “small equations.” If the calculation of probabilities is deployed, this is to precisely reveal causes which are, at their origin, secret, but which will gradually become less so and eventually conform to laws.  相似文献   
992.
Sébastien Breau 《对极》2014,46(1):13-33
The Occupy movement catalyzed public debate on the issue of growing income inequality. This paper examines recent patterns of inequality in Canada, paying particular attention to changes in the characteristics of the top 1% of income earners. At the national level, the gap between the top percentile and the other 99% has widened considerably: in 2006, 11% of the nation's income was concentrated in the hands of top earners (whose mean income of $344,000 is 11 times that of the average Canadian) compared with 7.7% just 15 years earlier. Beneath such national‐level figures lie important geographical differences in the income hierarchy: the thresholds, average incomes and socio‐economic characteristics of the top 1% vary widely across provinces and cities. Among the most important spatial shifts observed is the growing concentration of high‐income groups in energy‐rich Western Canada, where Calgary has become the most unequal city in the country.  相似文献   
993.
Thirteen bronze battleaxes from Middle Bronze Age II graves at Rishon LeZion, Israel were analysed by ED XRF at multiple surface locations in order to determine their metallurgical composition. Six of these were further subjected to neutron diffraction using an ENGIN‐X diffractometer in order to determine bulk phase composition. The results indicate that the previously established geographical and chronological variability in Sn–Cu (with occasional Pb) and As–Cu alloys found using the former method may be an artefact of preservation and conservation. In addition, the varying homogeneity determined by the latter reflects special treatment for improving on the metal cast.  相似文献   
994.
At Santa Filitica, a Roman settlement in north‐western Sardinia occupied until the ninth century ad , archaeological excavations have found the remnants of a furnace consisting of a semi‐circular base made of stony slabs and tiles bound with clay. The furnace is attached to a wall of Roman age. Layers of the sixth century ad , bearing several variously oxidized slags, were found close to the furnace. These findings first testify to an ironworks in Sardinia, within a well‐defined context. XRPD and SEM–EDS mineralogical and textural analyses suggest that the slags derive from a bloomery and smithing work that was the first evidence of this type documented in Sardinia during the Early Middle Ages. Chemical analyses (performed with ICP and INAA) of rare earth elements and trace elements in two slags and in two Sardinian iron deposits allow some conclusions to be drawn on the local provenance of the ore. Our comparison of the Sardinian findings and some slags representative of archaeological smelting sites at the front of Elba island—the largest and longest lived iron‐working sites in the Mediterranean—also improves the methodology with which iron slags derived from different ores are compared.  相似文献   
995.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
996.
Recent findings in the city of Reims have lead to the discovery of manufactured bone objects coloured in green throughout their entire volume. In order to discover the intentional nature of the colouration and to propose a colouration mechanism, modern ox bones have been coloured in the laboratory. Bones with a hue similar to that of the archaeological artefacts have been obtained by boiling in an acidic brine in a copper vessel. A combination of infrared spectroscopy, X‐ray diffraction and transmission electron microscope observations did not reveal the speciation of copper, but allowed us to validate the colouration process and to discuss the intentional origin of the colouration.  相似文献   
997.
998.
The chemical composition and petrographic features of 51 samples of fine pottery selected from the archaeological site of Syracuse have been established by means of optical microscopy and X‐ray fluorescence spectrometry, with the aim of creating a reference group for the ceramics produced in this important Greek colony during the Hellenistic–Roman period. This reference group is constrained by the analysis of six kiln wasters and of raw materials outcropping in the studied area. Among the studied findings, the main part is assignable imputably to local production, while some specimens probably come from Greece and other colonies (Messina and Gela). The Syracuse fine pottery is characterized by inclusions formed mainly by quartz and micaceous and fossiliferous groundmass. The used pastes were more or less purified through the removal of the sandy‐to‐coarse silty granulometric fraction. The multivariate statistical analysis of chemical data permits the identification of production at Syracuse on the basis of comparison with the kiln wasters and the Plio‐Pleistocene clays.  相似文献   
999.
To obtain accurate results in the RHX dating of ceramics, it is essential that the RHX measurements are continued until the rate of mass gain is constant with (time)1/4. In this paper, we discuss how the initial stages of mass gain are affected by the specific surface area (SSA) of the ceramic material. The paper provides guidance on experimental protocols to avoid dating results being distorted by relatively early‐time mass gain data.  相似文献   
1000.
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