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1.
王亦慧 《丝绸之路》2010,(12):89-90
作为世界美术史上的奇迹,敦煌飞天有着悠久而灿烂的历史,经历了千余年的岁月,展示出不同的时代特色和民族风格。从诞生至今,飞天那飘舞的衣裙一直影响和启迪着一代又一代艺术家,给人以美的享受。  相似文献   
2.
王哲 《历史地理研究》2021,41(2):119-138
近代中国邮政空间主要是以民信局、国营邮政、侨批等多种企业实体构成。清朝邮政成立后即开始蚕食小额民间资本支持下的民信局经营空间,而基于对1936年《中华民国邮政舆图》的数字化工作发现,历经40余年经营,国营邮政基本整合了全国范围内的邮政空间,也基本完成了本领域的“国进民退”。在此过程中,国营邮政审慎模仿民信局的经营方式,使用多种创新经营策略,除了在大中城市内部和城市之间构建了便捷快速的邮政网络空间,更借助邮政代办的方式以极低的成本将营业网络“下沉”到铁路和公路无法覆盖的农村地区,较好地与传统农村“定期市”网络完成耦合,基本达到了通商处必通邮的效果。国营邮政点和邮路集聚所形成的“邮政聚集区”也成为一种显著的近代化外在空间表征,同时成为界定所谓“核心—边缘”结构的系统可信、定量可验证的空间指标。  相似文献   
3.
The selection of a non-shattering phenotype is a pivotal change in the process of rice domestication. However, current research is heavily restricted by the preservation conditions of macro-plant remains in early and middle Neolithic sites, as very limited well-preserved rice spikelet bases could be retrieved. We present a non-destructive method based on micro-computed tomographic (CT) scanning, which could provide detailed visualization of the internal structures of charred spikelet bases and efficiently discriminate the shattering and non-shattering phenotypes of rice spikelet bases according to the abundance of fusiform echinate phytoliths. It could be widely applied in different contexts, especially those poorly preserved specimens and tempers in pottery sherds, greatly improving our knowledge of rice domestication.  相似文献   
4.
In archaeology, strontium isotope analysis is developing into an efficient scientific technique for tracing the movement of prehistoric humans and animals. Determining the local bioavailable 87Sr/86Sr ratio range is the key to distinguishing whether the human or animal is indigenous to the local area. It has been shown that the 87Sr/86Sr ratio in the enamel of pigs can be an excellent sample to determine the range of local strontium isotope ratio at the site. However, pigs may not be all local at the site, and there is no special study on whether pigs’ different ages and tooth types impact the local strontium isotope characteristics. In this paper, the tooth enamel of 19 pigs from the Zaoshugounao site for strontium isotope ratio (87Sr/86Sr) by multicollector–inductively coupled plasma mass spectrometry. There were no significant differences in 87Sr/86Sr ratios of local pigs at different months and different molar types, which did not affect the determination of the local strontium isotope standard. Based on the local strontium isotope ratio range (0.711056–0.711476), we found that five pigs were non-local. The Jing and Wei river basins (in Guanzhong basin) and northern Shaanxi are likely sources of non-pigs.  相似文献   
5.
Geographical distance constitutes friction in searching for research collaborators. Taking advantage of a quasinatural experiment featured by High-Speed Railway (HSR) lines in China, this paper employs the difference-in-differences model to identify the causal impact of a substantial improvement in the intercity transportation infrastructure on collaborative innovation across cities. The data pertain to a universe of patent applications filed by Chinese universities and their citations. We find that HSR contributes to a substantial increase in the innovation quantity and quality of collaborative patenting innovation between universities and corporates. It contributes to industry collaboration by utilizing university academic disciplines in the related technology fields. Lastly, HSR facilitates universities to search for new research partners with better quality beyond the geographical boundary.  相似文献   
6.
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   
7.
8.
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   
9.
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   
10.
Wang, Q., Wang, Y., Qi, Y., Wang, X., Choh, S.J., Lee, D.C. & Lee, D.J., November 2017. Yeongwol and the Carboniferous–Permian boundary in South Korea. Alcheringa 42, 245–258. ISSN 0311-5518

Six conodont and one fusuline zones are recognized on basis of a total of 25 conodont and 13 fusuline species (including seven unidentified species or species given with cf. or aff. in total) from the Bamchi Formation, Yeongwol, Korea. The conodont zones include the Streptognathodus bellus, S. isolatus, S. cristellaris, S. sigmoidalis, S. fusus and S. barskovi zones in ascending order, which can be correlated with the conodont zones spanning the uppermost Gzhelian to Asselian Age of the Permian globally. The fusuline zone is named the Rugosofusulina complicata–Pseudoschwagerina paraborealis zone. The co-occurrence of the conodont Streptognathodus isolatus (the Global Boundary Stratotype Section and Point index for the base of Permian) and Pseudoschwagerina (a Permian inflated fusuline) indicates that the Carboniferous–Permian boundary can be placed in the lower part of the Bamchi Formation in South Korea.

Qiulai Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yue Wang* [] LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yuping Qi* [] Xiangdong Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Suk-Joo Choh [] Department of Earth and Environmental Sciences, Korea University, Seoul 02841, Republic of Korea; Dong-Chan Lee [] Department of Earth Sciences Education, Chungbuk National University, Cheongju 28644, Republic of Korea; Dong-Jin Lee [] Department of Earth and Environmental Sciences, Andong National University, Andong 36729, Republic of Korea. *Also affiliated with: University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, PR China.  相似文献   

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