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排序方式: 共有515条查询结果,搜索用时 15 毫秒
91.
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   
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建立低碳城市发展模式和都市空间结构是当前城市规划的重要实践内容之一。结合对南京市江宁区典型居住区的调研数据,文章初步分析了城市居住区周边土地混合度对通勤交通碳排放的影响。结果表明:①城市中心区土地混合度与通勤交通碳排放呈高度负相关;②在通勤交通碳排放中,私家车通勤碳排放占主导地位;③不同小区居民通勤交通碳排放呈现明显差别,城市中心区居民低碳排通勤交通方式特征显著,而城郊居民通勤方式呈现高碳排特征;④城市中心区土地混合度与低碳出行比例呈高度正相关。未来,应适当提高各城市功能区土地混合度,改善居民的通勤结构,进而减少通勤交通产生的碳排放,构建低碳城市。  相似文献   
94.
This article conducts a comparative biographical analysis to explain why the Chinese Communist Party's (CCP) revolutionaries used non‐nationalist Marxism to boost a nationalist movement. It argues that these people, based on their own observations of the precommunist Chinese nationalism, thought that China lacked structural conditions for making a solid nationalist movement such as cultural homogeneity, mass literacy, and a shared pride in modern history. They thus turned to seek a non‐national ideology that could still fulfil the functions of integrating leading elites, mobilizing the masses, and motivating the patriots themselves. Then, to explain why the CCP leaders particularly adopted Marxism, this article draws comparison with the Kuomintang (non‐communist nationalists) elites who advocated for more patience and insistence to develop regular nationalism. The comparison shows that the CCP's impatient jump stemmed from their disadvantaged backgrounds that had limited their ideological horizon: lower‐class origins, narrow overseas experiences, poor education, and weak attachment to traditional culture. To pre‐existing literature, this article makes three contributions: (1) provides a more detailed interpretation of the CCP's diagnosis of Chinese nationalism; (2) explains why the same structural dilemmas produced nationalist and non‐nationalist responses alike; and (3) draws a biographical database of the CCP and the Kuomintang.  相似文献   
95.
96.
Recent work at the Qijia Culture type-site of Qijiaping in the Tao River valley of Gansu Province, China, has shed light on the complex nature of this early Bronze Age site. Situated at the intersection between the mixed pastoralists of eastern central Asia and the agriculturalists of China’s northern Central Plain, Qijia peoples absorbed, evolved, and transmitted products and technologies that shaped cultural developments in both directions. The Tao River Archaeological Project (TRAP) used a combination of surface survey, geophysics, digital mapping, and targeted excavation to expand our understanding of the multicomponent nature of Qijiaping. This included identifying potential habitation, mortuary, and production locales; examining site-wide ceramic use; mapping anomalies through geophysics; and further exploring these through targeted excavations. The results have expanded our knowledge of the site structure of Qijiaping and its place in the wider Qijia interaction sphere, while also confirming the usefulness of this methodology.  相似文献   
97.
Zheng, D., Zhang, Q., Nel, A., Jarzembowski, E.A., Zhou, Z., Chang, S.-C. &; Wang, B., May 2016. New damselflies (Odonata: Zygoptera: Hemiphlebiidae, Dysagrionidae) from mid-Cretaceous Burmese amber. Alcheringa XX, xxx–xxx. ISSN 0311-5518

Two damselflies, Burmahemiphlebia zhangi gen. et sp. nov. and Palaeodysagrion cretacicus gen. et sp. nov., are described from the mid-Cretaceous Burmese amber. Burmahemiphlebia zhangi is the first record of Hemiphlebiidae from this amber, although the family was cosmopolitan during the Mesozoic. It can be readily distinguished from all other members of Hemiphlebiidae in having very short MP and CuA veins, and in its rectangular discoidal cell. The new fossils support the view that hemiphlebiid damselflies were one of the dominant groups of Zygoptera during the Mesozoic. Palaeodysagrion cretacicus is the first dysagrionid damselfly from Burmese amber and the second Mesozoic representative of this predominantly Paleogene group. It differs from other members of Dysagrionidae in having a unique elongate discoidal cell. These new finds increase the diversity of damselflies in mid-Cretaceous Burmese amber.

Daran Zheng* [], Su-Chin Chang [], Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China; Qingqing Zhang [], Edmund A. Jarzembowski? [], Bo Wang? [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China; André Nel [], Institut de Systématique, Évolution, Biodiversité, ISYEB-UMR 7205-CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP 50, Entomologie, F-75005, Paris, France; Zhicheng Zhou [], The PLA Information Engineering University, 62 Kexue Ave, Gaoxin District, Zhengzhou 450002, Henan, PR China. *Also affiliated with State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, 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 Sciences, Beijing 100101, PR China.  相似文献   
98.
Y. Guan  Z. Y. Zhou  Y. Huan  X. Gao 《Archaeometry》2015,57(6):949-965
The application of heat‐treatment technology on lithic raw materials is an important feature of early modern human behaviour. The evidence of heat‐treated stone artefacts discovered at Localities 2 and 12 of the Shuidonggou Late Palaeolithic site, North‐West China, provides an important example for studying this technology among ancient humans in Asia during the Late Palaeolithic. The mechanism and effects of heat treatment on raw materials and the role of this technology in producing stone tools were studied by means of a simulation experiment and related analytical methods. These facilitated an in‐depth analysis of the heat‐treatment activities of the Shuidonggou occupants and their implications for cognitive ability and survival strategies of human populations at that time.  相似文献   
99.
唐宋时期在太湖湖流的作用下,太湖南岸形成一条地势较高的滨湖沉积带,吴越时在太湖湖滨开挖溇港,创建湖堤。入宋以后,在太湖南部碟型洼地的平原地形中,产生了横塘纵溇的水利结构?崽劣胱轀鞠嗯浜现饕?是为成功地向太湖排出平原洪涝水,两宋时对横塘纵溇结构的完善主要体现为溇港的设闸与横塘的加筑扑问逼诘?水利建设奠定了后期太湖南岸地区农田水利开发的基本格局。  相似文献   
100.
秦南海郡辖南海县说商榷   总被引:1,自引:0,他引:1  
本文通过对传世古官印"南海司空"之性质和新出土南越国木简所见"南海"地名之性质的重新研究,对秦南海郡辖有南海县说进行了商榷,认为所谓传世秦官印"南海司空"估计是南越国官印的误断,南越国木简所见"南海"地名指的当是南越国的南海郡,也不能排除是指南海郡治(即南越国都番禺城)的可能性,但没有任何证据可以证明指的是南海县,有学者推测秦代与南越国时期一样也设有南海县,显然缺乏立论的根基。  相似文献   
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