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1.
贵州贡院建于明嘉靖十六年首开乡闱时,其发展历程正是贵州科举史的缩影。其结构及功能与他省贡院相似,规模居于全国中下等,号舍最少时不足千间,最多时超过四千间。其明末毁于战火,清代重建后亦频繁维修,经费则以公款为主,辅以民间捐助。  相似文献   
2.
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   
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While research has tackled the hub-and-spoke network design problem, that research has overlooked the air-truck modal integration issue which is a common feature of real express delivery systems. This paper devises integer linear programs to represent the mode and route assignment aspects of the operational problem. The model is solved under four different levels of delivery schedule, and the results show that as the promised delivery schedule is relaxed, not only does the use of truck routes become more desirable, but also interesting adjustments in mode and hub assignment occur. Consider the case of hubs in Los Angeles and Dayton. As the time constraints are relaxed, cities such as Minneapolis and New Orleans originally linked by air to Los Angeles, switch to Dayton because cheaper truck routes become feasible.  相似文献   
5.
本文通过 X 射线衍射(XRD)、差热分析(DTA)、发射光谱分析(ESA)、扫描电镜(SEM)和能量色散 X 射线分析(EDAX)的方法,对古耀州青瓷所用原料及其矿物组成,古瓷器的烧成温度和显微结构进行了分析研究。得出耀瓷乃是使用当地高岭石和伊利石粘土矿物为原料烧制而成,烧成温度在1200℃以上的结论.  相似文献   
6.
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   
7.
张勇 《安徽史学》2021,(1):135-142
北宋时期,朝廷在淮南地区运河沿岸州军设置转般仓,这些州军具有了转般粮食物资进京的功能;又先后置发运司于真州和泗州,使其开始具有总管东南漕运事务的职能;盐利也集中于此,同时亦掌控着地方物资的上供经费.其他物资转输区域则经常出现改变转运方式的情形,中转区域改变了起始区域输出物资的运输方式,减轻了部分运输成本.起始区域在加重中转区域负担的同时,亦对中转区域的经济繁荣有促进作用.  相似文献   
8.
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   
9.
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   
10.
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   
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