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11.
古铜矿遗址围岩表层有害生物的防治 总被引:3,自引:0,他引:3
铜绿山古铜矿遗址地处长江中游地区、空气湿度大、围岩表层有害生物成片生长蔓延,对遗址的长期保护造成极大威胁。对此采取了改变遗址的环境条件、喷涂消杀药品的方法,消除了围岩表层有害生物的危害。经过一年半的观察表明该方法是可行的。 相似文献
12.
试论人类身高的地域差异规律及其成因 总被引:1,自引:0,他引:1
人类身高高纬高于低纬,牧区高于农区、沿海高于内地、低海拔高于高海拔、城市高于农村、发达国家高于发展中国家。其主要原因是气温的高低、光照的多少和营养的差异。 相似文献
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本文论述了图们江地区国际性城市体系建设的必要性,提出了城市体系等级结构、职能结构和空间结构的构建设想及管理原则,并初步估算了城市体系发展各项基础设施建设及投资规模。 相似文献
14.
Investigating Human Migration and Horse‐Trading in Yelang (夜郎) Through Strontium Isotope Analysis of Skeletons from Zhougshui Sites,South‐West China (1300 bc – ad 25)
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Yelang (夜郎), a mysterious state located in the south‐western area of early China and dating from the Bronze Age to the Early Iron Age (1300 bc – ad 25), is a cultural interactive junction between the Yunnan–Guizhou Plateau and the Yangtze River Basin. The Zhongshui Basin in Weining County, Guizhou Province, was one of the important distribution areas of the Yelang civilization. This area, which includes sites at Jigongshan (鸡公山; 1300 – 800 bc ), Hongyingpan (红营盘; 700 – 400 bc ) and Yinzitan (银子坛; 400 bc – ad 25), has provided a very integrated chronology, spanning from the Bronze Age to the Early Iron Age in the eastern Yunnan – western Guizhou area. To investigate human migration and horse‐trading at these Yelang sites, we conducted a strontium isotopic analysis on the teeth enamel of humans and horses unearthed from these three sites. The results indicated the following: (1) people at the earlier sites (Jigongshan and Hongyingpan) were all indigenous, whereas in the Yinzitan cemetery, there was a more immigrant population, and all the people who were buried in an upper limb flexed supine position were non‐local; and (2) most of the horses found at the Jigongshan and Yinzitan sites show different provenances, probably related to the famous Dian (滇) and Zuo (筰) horses recorded in historical documents, providing more clues for further study on horse‐trading in South‐West China during the Bronze Age and the Early Iron Age. 相似文献
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复色釉陶是汉代低温铅釉陶中的一个特殊品种,其施釉烧制工艺系在普通单色釉陶的基础上,于一件器物上施加两种及以上釉料,以低温一次入窑烧制而成,呈现出绚丽的艺术效果,达到了汉代釉陶的高峰。此类釉陶主要分布于宝鸡、济源和延安及其周边地区;最早出现于西汉中晚期,流行于西汉晚期至东汉初期。就施釉工艺而言,其多色施釉技术与北魏时期的二色釉陶一脉相承,并在北齐时期与新出现的"瓷胎铅釉陶"二次烧制技术相结合,形成了北齐特有的多色瓷胎铅釉陶器,为后来唐三彩的出现奠定了技术基础。 相似文献
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滕州前掌大墓地中随葬兵器的墓葬较多,特别是女性墓葬中随葬兵器的现象较之于其他地区更为多见亦罕见于海岱地区。产生这种现象的原因可能与商末周初时女性社会地位较高和前掌大地处战事频繁的东夷重地有关,也许正因如此,前掌大墓地的女性生前可能参与作战。 相似文献
18.
Xinzheng Lu Yuan Tian Song Cen Hong Guan Linlin Xie Lisha Wang 《Journal of Earthquake Engineering》2018,22(9):1662-1682
Shear walls are important lateral force-resistant components of tall buildings. Hence, a reliable numerical model that can accurately represent the mechanical characteristics and large deformations of shear walls is critical for realistic collapse simulation of tall buildings. Based on the theory of generalized conforming element, a high-performance quadrilateral flat shell element, NLDKGQ, accounting for the large deformation using the updated Lagrangian formulation, is proposed herein and implemented in OpenSees. The reliability of NLDKGQ is validated using classical benchmark problems and reinforced concrete specimens. In addition, its capability in simulating the collapse of a tall building is also demonstrated. 相似文献
19.
Tao Wang 《Eurasian Geography and Economics》2018,59(2):224-245
AbstractA huge flow of internal migrants in China is an indicator of the significant changes in the geographical and cultural patterns brought by China’s recent economic growth. The Hui (10.6 million), as one of the largest ethnic minority groups in China, and the Dongxiang, with almost 100% of them holding the Islamic belief, are migrating from rural areas to urban centers in Northwest China. Analyzing the qualitative data from narrative stories, thematic photos, group discussions, semi-structured interviews, and field observations, this study interprets the cultural experience of rural Muslim migrant students in Chinese public schools and examines their complex and fluid rural–urban identities. This study further discusses the possibilities of including and integrating rural migrant students in cities. 相似文献
20.
Edmund A. Jarzembowski Bo Wang Daran Zheng 《Alcheringa: An Australasian Journal of Paleontology》2018,42(1):110-114
Jarzembowski, Edmund A., Wang, B. &; Zheng, D., October 2017. A slender new archaic beetle in Burmese amber (Coleoptera: Archostemata). Alcheringa 42, 110–114. ISSN 0311-5518.A new archostematan beetle, Clessidromma palmeri gen. et sp. nov. (Insecta: Coleoptera) is described from mid-Cretaceous Burmese amber from northern Myanmar. It has a uniquely specialized body form for which a new stem tribe, Clessidromatini trib. nov., is proposed in the subfamily Ommatinae of the family Cupedidae sensu lato.Edmund Jarzembowski* [jarzembowski2@live. co. uk] Bo Wang? [bowang@nigpas. ac. cn] and Daran Zheng? [darzheng@connect. hku. hk] State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Rd, Nanjing 210008, PR China. *Also affiliated with: Department of Earth Sciences, The Natural History Museum, London SW7 5BD, UK. ?Also affiliated with: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Science, Beijing 100101, PR China. ?Also affiliated with: Daran Zheng, Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China. 相似文献