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21.
青铜文物锈蚀机理及有害锈转化剂研究   总被引:4,自引:0,他引:4  
为保护好出土青铜物,防止“青铜病”蔓延,必须除去有害锈,为此作了青铜器锈蚀机理的模拟性验证实验。依据电化学原理,经6次配方筛选和多次工艺条件试验,研制出能将青铜器中有害锈转化为无害锈的转化剂,它可特有害锈中的CT转化成Cl2、Cu^ 转化为Cu^2 和Cu,从而制止“青铜病”的蔓延。用此方法对青铜物进行保护,在大气中存放7年,至今保护完好,无锈点。  相似文献   
22.
阿勒泰地区位于新疆的最北端,与欧亚草原之间存在丰富的文化交流,而冶金技术的发展与人类文明紧密相关,为探究新疆阿勒泰地区的冶金发展情况,选取9件草原游牧文化的代表性器物——铜鍑和马具,使用金相显微镜、扫描电子显微镜和X射线能谱仪及双通道电感耦合等离子体发射光谱仪,对16个样品进行金相组织分析和成分分析,并探讨其制作技术特征。研究发现阿勒泰地区的早期铁器时代铜器普遍采用范铸工艺,其成分主要为红铜、砷铜、铅砷青铜。该分析结果为研究新疆阿勒泰地区的冶金发展提供了重要参考。  相似文献   
23.
This research aims at delineating the dietary practices in Central Italy during the Bronze Age. The study of food choices is a mean for investigating palaeoenvironmental agricultural and economic activities and social relationships, which have been little explored until now in Italy from this specific perspective. Recent researches have showed that the Middle Bronze Age is a crucial period of dietary changes in Italy. Following these first observations, we studied three Bronze Age sites in Tuscany and Latium: Grotta dello Scoglietto, Grotta Misa and Felcetone. Analyses of stable carbon, nitrogen and sulphur isotopes on 38 human and 22 animal collagen samples were performed. The results show three different dietary patterns. Data from Grotta dello Scoglietto (Early Bronze Age) indicate a high‐protein intake, with a probable consumption of fish. Additionally, sulphur results let us infer the presence of some non‐local people. Individuals from Felcetone (Initial phase of the Middle Bronze Age) show a terrestrial diet dominated by plant proteins, which suggests a low δ15N food intake, namely legumes, as well as C4 plant, such as millet. Finally, values from Grotta Misa (Middle Bronze Age) highlight a mixed terrestrial diet and the consumption of millet. Given the variety of the obtained results, we are able to conclude that the transition from the Early to the Middle Bronze Age represents a moment of change, which is reflected by the presence of different dietary patterns. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
24.
The paper describes and analyses recent finds of the European pond turtle (Emys orbicularis) from the archaeological sites at Obříství (Mělník District, at the confluence of the Elbe and Moldau rivers in the Bohemian Basin, Czech Republic). Turtle remains were found in three sunken features dated to the Late Bronze Age or to the Hallstatt period, and in one feature dated to the Neolithic. The high number of osteological finds, particularly the number of individuals found in one place, is unique within Bohemia and very rare for the Bronze Age to Iron Age in Europe. A large number of shell remains were identified, from at least 12 individuals in feature 1480, and from at least 5 individuals in feature 1483. The high numbers support the hypothesis that the European pond turtle was once a regular feature of the local fauna, even though the Bohemian basin is surrounded by mountains, which will have presented difficulties for the process of postglacial recolonization by semiaquatic thermophilous reptiles. The findings from Obříství show evidence of the exploitation of turtles for food. Signs of culinary procedures and the human consumption of turtles include anthropogenic chop marks, signs of burning and the apparently intentional segmentation of the turtle bodies. The quantity of turtle bones is still negligible, however, compared with those of mammals. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
25.
Stable oxygen isotope ratios in archaeological human dental enamel represent an under‐utilised tool in the examination of changing climatic patterns in the ancient world. In the Oman Peninsula at the end of the third millennium bc , rapid aridification was accompanied by a breakdown in interregional trade relations; however, the human response to these changes is poorly understood. At the Bronze Age necropolis at Shimal in the United Arab Emirates, dental enamel from individuals interred in both Umm an‐Nar (ca 2700–2000 bc ) and Wadi Suq (ca 2000–1300 bc ) tombs underwent oxygen, strontium and carbon isotope analyses to examine how local inhabitants of southeastern Arabia responded to both environmental and socioeconomic change. While individuals from Shimal exhibit a clear shift in mean δ18Oc(VPDB) values from the Umm an‐Nar (−3.5 ± 0.6‰, 1σ) to the Wadi Suq (−2.4 ± 0.9‰, 1σ), corresponding 87Sr/86Sr and δ13Cap signatures display homogeneity indicative of continuity in Bronze Age lifeways. Together, these data highlight the ability of local communities to successfully adapt to their changing environs (in lieu of societal collapse or a shift to a more mobile lifestyle) in an effort to maintain their way of life. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
26.
Within Iran, there is little archaeological evidence for relationships between newly arrived Early Trans-Caucasian (ETC) or Kura-Araxes settlers and earlier inhabitants and contact with neighbouring cultures, or for their apparently abrupt end. Based on the evidence, the Iranian Kura-Araxes was not a simple ‘copy' of the Caucasian Kura-Araxes package. Ceramic traditions show local peculiarities, and all are elements suggesting that the Kura-Araxes traditions went through processes of adaptation, change and re-elaboration according to local tastes and technologies. In this study, an archaeometric approach to ceramics in the Kolyaei Plain of central Zagros contributes to the discussion of contact and exchange between indigenous communities and several cultural spheres of influence on the Early Bronze Age (beginning in the fourth millennium bce ). Morphological data, as well as the mineralogical and chemical composition of ceramics, were applied to determine the major and trace elements of the pottery shards. Based on the trace element profiles, it can be suggested that all the pottery shards are in the same group and they strongly are local products. The ceramic provenance indicates the same patterns of material interactions during the ETC or Kura-Araxes in all the sites within the Kolyaei Plain.  相似文献   
27.
Fourteen glass objects recovered from excavations at the ancient city of Tall Zirā‛a, Jordan, were analysed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to determine the period and origin of manufacture. The composition of glasses manufactured in the Late Bronze Age (LBA) and Iron Age are distinctly different, therefore major element analysis can be used to distinguish between the groups relatively easily. The LA-ICP-MS analysis provided quantitative trace element data which were used to determine the provenance of those glasses identified as LBA. This research discusses the implications of the presence of both Egyptian and Mesopotamian LBA glasses and examines the varying compositions and colour strategies employed in both the LBA and Iron Age objects. Specifically, glass in the LBA was considered to be one of the highest status items attainable, playing an instrumental role in diplomatic gift-giving. When considered with the archaeological information, the significance of these finds at Tall Zirā‛a indicates that this city was a settlement of high status, not primarily a convenient trading stop on the Transjordan route.  相似文献   
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ABSTRACT

Nuclear cooperation has been a consistent feature of the Australia-US alliance. In the 1950s and 1960s, Canberra explored transferring US nuclear weapons to Australian forces operating in Southeast Asia. Since the 1960s, Australian governments have supported hosting joint facilities that contribute to America’s ability to execute global nuclear operations. And Australia has regularly invoked the nuclear umbrella as part of the alliance. We explain the key sources of nuclear cooperation in the alliance by leveraging realist and institutionalist theories of alliance cooperation. While realism explains limits to US nuclear commitments in the 1950s, institutional explanations are more relevant in pinpointing the sources of nuclear cooperation and in explaining why Australia has often achieved its policy preferences as the junior partner.  相似文献   
30.
Oral cleft (OC) is a common congenital anomaly in humans, which occurs in approximately one per 700 live births. However, cleft skulls are found relatively seldom in archaeological specimens, especially for the bc period. Mortality of infants with OC was apparently high because of breastfeeding difficulties and culturally sanctioned rejection of them in the past. This paper presents one of the most ancient cases of OC in Eurasia. The finding comes from the Middle Bronze Age pastoralists' cemetery in Altai, Russia. The skeletal remains have been radiocarbon dated to 1883–1665 cal bc . Cranial and dental measurements, computed tomography and radiography have been used to examine this malformation. The facial sculpting reconstruction has been performed to visualise the ante mortem appearance of the cleft face. Besides, δ13C and δ15N isotope analysis was used for a comparative study of the diet of the cleft individual. It has been established that a young man from Altai was affected by complete bilateral cleft lip and alveolus, which is a very rare form of typical OC. This defect is associated with dental anomalies such as hypodontia, microdontia, and ectopia as well as with dysmorphology of the facial complex outside the cleft area, including mild hypertelorism, hypoplasia of nasal bones and antheroposterior maxillary deficiency. Furthermore, aplasia of the frontal sinuses and the sacral spina bifida occulta have been observed. These findings are consistent with clinical data indicating strong correlation between development of a major defect and multiple minor anomalies. The results of the study also suggest that there was tolerant attitude towards the facial deformities among the ancient Altai pastoralists. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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