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51.
青海大通县出土汉代玻璃的研究 总被引:1,自引:0,他引:1
本文共对12件玻璃样品进行化学组成分析.其中,部分样品还进行了密度测定,X 射线衍射分析和显微镜观察.此外,还对一颗黄色玻璃珠的表面层进行 SEM-EDX 分析.结果表明,该玻璃珠表面有金箔涂层.根据分析结果,青海大通县出土玻璃的基础成分可归为三类,即铅钡玻璃(Na_2O-PbO-BaO-SiO_2系统玻璃),钠钙玻璃和钾硅玻璃(K_2O-SiO_2系统)。此外,还对玻璃的来源进行了探讨. 相似文献
52.
随着高等教育规模的不断扩大和高校管理体制的改革的进一步深入,高校学生管理体制、方法和手段出现了弱化和改革滞后的现象,大学生违纪现象呈逐渐上升趋势。本文从当前高校大学生违纪的现象与特点入手,对其原因进行探究,并对如何减少违纪现象的出现、杜绝违法案件的发生提出了一些预防对策。 相似文献
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G.R. Shi Fang Zongjie N.W. Archbold 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):81-101
The present paper describes and illustrates an Early Permian brachiopod fauna collected from two localities from the upper part of the type Dingjiazhai Formation near Youwang, 30 km south of Baoshan in the Baoshan block, western Yunnan, China. The brachiopod fauna is dominated by Stenoscisma sp. and Elivina yunnanensis sp. nov. and exhibits strong generic and some specific links with faunas from the Bisnain assemblage of Timor and the Callytharra Formation of Western Australia and, to a lesser extent, faunas from the Jilong Formation of southern Tibet, the Tashkazyk Formation of southeastern Pamir, the lower Toinlungkongba Formation of northwestern Tibet, the upper Pondo Group of central Tibet, and the Jimba Jimba Calcarenite of the Carnarvon Basin, Western Australia. Based on these correlations, a Late Sakmarian (Sterlitamakian) age is preferred for the Dingjiazhai brachiopod fauna. Two new species are proposed: Globiella youwangensis sp. nov. and Elivina yunnanensis sp. nov. 相似文献
55.
Hui Zhang Meifeng Shi Wei Shen Zhiguo Li Bingjian Zhang Renzhi Liu Runping Zhang 《Journal of archaeological science》2013,40(2):935-942
Black crusts, such as dust deposit and smoked smudge, are the main pollutants in Yungang Grottoes, the world famous Buddhist heritage site. It is always considered that the black crust should be removed during the conservation process of stones. In this paper, the investigation of the role of smoked crust on the Yungang sandstones was performed to verify if the smoked layer on the stone surface would be harmful or protective. The results of SO2 corrosion experiments with and without water both show that the samples covered with smoked layer can play a protective role on the sandstones, which means that the smoked layer on the stones can prevent the attack of SO2 and water, the major deterioration agents in Yungang area. The multi-factor deterioration cycle experiments, including salt crystallization, freeze–thaw damage, wet–dry cycle and acid corrosion, also indicate that the smoked samples are less deteriorated and salt crystallization is the most severe damage to the sandstones. 相似文献
56.
正ISBN:978-1-934536-68-1,pp.136,31 color,9 b/w illus,$59.95.Since"The Belt and Road Initiative"reviving the ancient trade land and maritime trade routes was proposed by the Chinese state at the end of 2013,the routes linking East and West by land and sea,whereby silk,spice,and glass were transported by ship or camel,are frequently mentioned.From East Asia to Europe,it garners increasing attention from institutes,think-tanks,and forums 相似文献
57.
Chao-Fan Shi Yong-Jie Wang Qiang Yang 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):309-318
SHI, C.F., WANG, Y.J., YANG, Q. & REN, D., September 2012. Chorilingia (Neuroptera: Grammolingiidae): a new genus of lacewings with four species from the Middle Jurassic of Inner Mongolia, China. Alcheringa 36, 311–320. ISSN 0311-5518. A new grammolingiid genus, Chorilingia containing four new species (C. euryptera, C. parvica, C. translucida and C. peregrina) is described and illustrated from the Jiulongshan Formation at Daohugou, Inner Mongolia, China. The new genus is differentiated mainly on the first branch of vein Rs (Rs1) separating distal to the forks of both CuA and CuP. A key to species of the genus is provided. 相似文献
58.
文章从明代两浙盐政变革的制度背景出发,考察永嘉盐场成弘时期的盐课改折、嘉靖前期的盐课转嫁、嘉靖后期的私盐倭乱、隆庆年间的赋役改革等历史事件,探讨该过程中州县官府与盐场地方势力之间的复杂利益博弈。对永嘉盐场的个案研究,或许有助于增进我们对明代盐场赋役制度运作和东南沿海社会变迁的理解。 相似文献
59.
<正>目次一《保训》释文二竹书之"埶"与测阴阳三舜求地中的故事四微变地中的故事五地中变迁的考古学与文献学证据六周人居中而治思想的传承七地中变迁与夏商都邑的关系八结论清华大学所藏战国竹书《保训》是一篇颇具价值的先秦古遗书,自刊布以来,学者研释不绝,对通晓文意,揭示其思想有很大帮助。然因竹书某些关键字词的释读多有争议,致学者就竹书内容的理解仍颇存分歧。笔者以为,竹书宗旨乃在阐明居中而治的传统政治观,其中尤为重要者,则在于保留了久已失载的有关古人对于地中的求测及早晚地中变迁的史实。今就相关问题阐释考述。 相似文献
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