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51.
本文利用扫描电镜、X射线衍射仪与电子探针能谱仪对安徽繁昌窑青白瓷釉的显微结构、物相和化学组成进行了分析,并与同时期的湖北青山窑和江西景德镇窑青白瓷釉进行了对比研究,认为繁昌窑青白瓷釉属于钙系釉中钙釉类型,其瓷釉配方工艺与青山窑与湖田窑相似,应由一种“釉石”加入石灰石及草木灰制成。  相似文献   
52.
营城子汉墓位于辽宁省大连市甘井子区,是我国东北地区一处重要的大型汉墓群。营城子汉墓出土了一批玻璃耳珰,为探讨其成型工艺及来源,采用超景深显微系统进行了表面形貌观察,初步认为是模铸成型,并经过打磨。采用便携式X射线荧光光谱仪(XRF)进行了化学成分分析,结果显示,它们分属铅钡硅酸盐和钾硅酸盐玻璃系统,一件由Cu2+着色,其余主要由Co2+着色。其为我国自制,所用钴料来源相同,钴料的锰钴比特征与国产钴土矿的类似。并对营城子汉墓出土玻璃耳珰造型与化学成分体系间的关系进行了分析,对玻璃耳珰制作模式进行了初步探讨,进一步加深了对我国古代玻璃耳珰制作与传播的认识。  相似文献   
53.
Excavations at Soba, the capital of Alwa, between 2019 and 2022 yielded more than 30 glass fragments in addition to a glass cosmetic bottle. An analysis of 30 glass samples has identified glass belonging to a number of compositional groups. The majority of fragments were made of plant ash-soda glass produced in the Middle East (Iran, Iraq) between the 9th and 10th centuries, and in the Eastern Mediterranean (Levant and Egypt) between the mid-10th and mid-12th centuries. Seven fragments were made of mineral–soda-lime glass produced in 9th-century Egypt and three high-lead glasses find analogies in the 9th- to 11th-century glass. Archeological evidence, as well as textual sources, leave no doubt about Alwa’s intense transcultural connections. This article provides the first insight into the chemistry of glass shards from medieval Nubia, and the results of analysis contribute to evidence for long-distance contacts of Soba, the capital of one of the medieval kingdoms of Sahelian Africa.  相似文献   
54.
The chemical composition of 18 glass beads from Early Sarmatian period burials were determined using electron probe microbeam analysis and energy dispersive X-ray fluorescence. The beads were made from high-magnesia-soda-lime-silica glass, leaded-soda-lime-silica glass, low-magnesia-soda-lime-silica glass and low-magnesia-high-potash glass. Multivariate analysis of the major oxides suggests that there are five distinct glass recipes used to manufacture these beads. These various glass recipes indicate the involvement of the Sarmatians in exchange/trade networks linking the Eastern Mediterranean, the Indian subcontinent, and China.  相似文献   
55.
We examined the hedonic price of neighborhood racial composition across a sample of 180 US housing markets and compared heterogeneity in results. Statistically significant estimated price elasticities calculated at the mean ranged from ?0.61 to 0.2 and ?0.26 to 0.21, for increases in Black and Hispanic neighborhood proportion, respectively. Hedonic price discounts for Black neighborhoods were greater when land supply was more inelastic, when the land value share of the housing cost was greater, and in the southern portion of the United States. Hedonic price discounts associated with Hispanic neighborhoods exhibited no patterns relative to geography or housing supply factors.  相似文献   
56.
This article presents a comprehensive study of the local soils and historic earthen building materials used in Nako temple complex in Western Himalayas. On-site and laboratory investigations followed a holistic approach to characterize materials and identify historic manufacturing formulas. The interdisciplinary and novel methodology used for analysis of the earthen building materials combine geological, chemical, mineralogical, geotechnical, and mechanical approach. The results presented in this article enable a better understanding of material culture and advance the study of damage and decay processes found in the temple buildings. In addition, a suitable conservation and preservation strategy is presented.  相似文献   
57.
为探讨北京昌平沙河镇墓葬出土的三枚蜻蜓眼玻璃珠的质地和来源,利用X射线衍射分析(XRD)、激光拉曼光谱分析(LRS)、便携式能量色散X射线荧光分析(PXRF)三种无损分析方法,对玻璃珠基体和眼珠分别进行了结构和化学组成的无损伤测试。结果表明,这三枚蜻蜓眼珠的基质为玻璃态物质,其化学成分表明该玻璃属于钠钙硅酸盐(Na2OCaOSiO2)系统;Cu和Co是主要的着色元素。考虑到三枚珠子采用的钴料成分为高铁低锰的进口钴料,同时通过与国内外相似珠子的对比,推测这三枚蜻蜓眼玻璃珠是外国进口物的可能性较高。蜻蜓眼玻璃珠所在墓葬群虽为清代,但根据初步的分析研究可推断,墓主通过收藏或其他途径获得并将其作为随葬品。  相似文献   
58.
Abstract

This is an in-depth study of the parish of Hvalsnes, a small fishing community situated on the Reykjanes peninsula in southwestern Iceland, during the period 1750–1850. The study is inspired by the nordic Coastal Region Project carried out in the 1990s, focussing on the relationship between economic factors and household size and structure. With reference to the concept of ecotype, Hvalsnes is compared to a few farming communities in southern and western Iceland as regards a number of economic and demographic factors. Among the features characterizing the Hvalsnes community was the large proportion of crofter and cottar households in relation to those of independent farmer-fishermen; the former constituted a valuable workforce for the commercial cod fisheries on the abundant Reykjanes banks. At the same time, the study reveals that during the winter season the operation of the fishing fleet was highly dependent on seasonal migration from farming areas. In this perspective Hvalsnes appears to be an Icelandic parallel to Lofoten in Norway. A closer view of the techniques and social organization of fishing in the parish discloses significant differences between its three individual sections. It is argued that these differences help to explain why some sections suffered more, in economic and demographic terms, than others from the natural catastrophes and political changes which took place towards the end of the eighteenth century. However, these changes did not alter the general condition of the landless population: cottars by the seaside and living-in servants in the countryside. Among these groups many individuals continued now as before their seasonal migration between the two ecotypes. Tentatively, it is argued that the seasonal exchange of workforce between fishing and farming communities contributed to an efficient use of the labour capacity of their members.  相似文献   
59.
60.
Concern about the quantity and quality of its labour force has been one of the major factors in bringing about a reversal of Singapore's population policy from anti‐natal to pro‐natal. In addition, the new policy has sought to enhance the quality of the workforce by offering incentives to encourage larger families amongst the more educated Singaporeans. After five years, responses have been muted, partly because of a growing sense of resentment amongst the younger adults towards interference in what are regarded as family decisions.  相似文献   
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