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Fossilized resin, or amber, has been examined from 120 worldwide sources by 1D and 2D proton magnetic resonance spectroscopy in solution. These spectra fall into five categories, corresponding to the classes already established by mass spectrometry and carbon‐13 magnetic resonance spectroscopy. The wide availability of this technique provides a straightforward method to classify amber rapidly and inexpensively.  相似文献   
373.
Ancient glass vessel fragments belonging to the seventh to ninth centuries ad , from the Ko Kho Khao, Laem Pho and Khuan Lukpad sites in southern Thailand, were studied. The glass vessel fragment samples are a collection belonging to the Department of Archaeology, the 15th Regional Office of Fine Arts of Thailand. The chemical compositions of the glasses were analysed using a modified portable energy‐dispersive X‐ray fluorescence spectrometer (OURSTEX 100FA‐II) by the introduction of a MOXTEK® AP3.3 polymer window (5 mm2?) to the KETEK silicon drift detector for the measurement of light elements. The non‐destructive analysis was performed at the National Museum, Phuket, in Thailand. It is shown that the glass chemical compositions belong to mineral and plant‐ash based soda–lime–silicate glass. The origins of the glass artefacts are discussed in terms of raw materials and glass decoration, and compared with previously reported similar typological glasses from sites in the port city of Rāya and the Monastery of Wadi al‐Tur in Egypt.  相似文献   
374.
Lead isotope and element composition analyses were performed by thermal ionization mass spectrometry (TIMS) and inductively coupled plasma optical emission spectroscopy (ICP–OES) on bronze helmets from royal tomb No. 1004 at Yin Ruins, the last capital of China's Shang Dynasty (17th to 11th centuries bc ). The data show that the copper‐based alloy helmets can be divided into two categories: tin bronze and leaded tin bronze; and the lead isotope ratios for both categories are in the range of highly radiogenic lead (HRL). This result offers some important clues to answering questions concerning the provenance of raw metal materials, as well as the chronology of this famous royal tomb.  相似文献   
375.
Nitrogen and carbon isotope compositions were measured in the bone collagen from a total of 86 prehispanic samples of the Canary Islands, and hydrogen in 70, all of them with enough amount of bone collagen, and adequate N and C content. These samples belong to prehistoric population of El Hierro (n = 27), Tenerife (n = 18), and Gran Canaria (n = 41). Isotope compositions were also obtained for prehistoric and modern food resources that were likely consumed by these people. Marked differences were observed among the three islands regarding the three isotopes analyzed: the δ15N values were highest among the population of Gran Canaria (10.8‰ ± 0.9‰), who also showed the highest δD values (7 ± 8‰). The population of El Hierro showed the highest δ13C values (−18.6‰ ± 0.7‰). These data suggest a high consumption of marine products by the population from El Hierro, and also an important consumption of terrestrial meat or marine, piscivore fish, by the population from Gran Canaria, together with domesticated C3 plants (barley and/or wheat), fruits of Ficus carica and other wild species, and goat products. Additionally, marked differences were observed between men and women, which suggest that women consumed a more vegetal-based diet, a finding which is in agreement with the higher proportion of teeth with carious lesions among women.  相似文献   
376.
Excavation of a medieval shipwreck at Novy Svet, Crimea, Ukraine, revealed an exceptional quantity of glazed ceramics with sgraffito decoration which, according to chemical analysis, correspond to a single production provisionally named ‘Novy Svet Ware’. Typological and analytical definitions are given. Its diffusion in the Crimea and extending to Turkey and the Levant, points to a main, as yet unlocated, workshop. The Novy Svet shipwreck suggests the persistence of large‐scale diffusion of ceramics in the late‐13th century, and demonstrates connections with the Black Sea, the Byzantine capital and territories, the Mediterranean and possibly the spice roads. © 2009 The Authors  相似文献   
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For several years, the authors have used lead isotope analysis to investigate extensively the provenance of ancient bronze or copper artifacts which had been excavated mainly from Japanese archaeological sites. The results have been published item by item in several relevant Japanese journals. This review is intended to give an account which will review the whole work relating early Japanese bronze culture to Chinese and Korean cultures through lead isotope study.  相似文献   
379.
A general view of the field of librarianship in Kuwait is presented with special emphasis on the impact of the Iraqi aggression on libraries and information centers in the country. First, a review of the damages and future plans of the main library and information sectors is presented (school, public, academic, central libraries), followed by a summary of the effect of the Iraqi occupation on education in library and information science.  相似文献   
380.
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