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101.
We drove from Beijing to Tianjin,guided by GPS.We got lost several times in the crowded city and had to continually send messages to Mr.Liu Dong to get directions by mobile phone.Finally in the thick of the city buildings,we found a Tibetan-style flat-roofed building that was colored red and white  相似文献   
102.
Using a set of modern/young (0 to about 200 years old) dust samples collected from the Chinese Loess Plateau the bleachability of IRSL measured at 50°C (IR50) and post-IR50 elevated temperature IRSL (measured at 225°C and at 290°C) is investigated by measuring the apparent (residual) doses recorded by these signals. Doses recorded by quartz OSL are used as a reference. Allowing for differences in dose rates it seems that both IRSL and post-IR IRSL signals yield residual doses that are significantly larger than the doses measured in quartz. These residual doses can be largely explained by thermal transfer caused by preheating. Nevertheless, we advise against the use of a low temperature preheat (<200°C) with IR50 to date loess samples because, as has been reported before, the signal appears to be thermally unstable. In general, we conclude that it may not be advisable to apply post-IR IRSL dating to Chinese loess samples where residuals of up to ∼20 Gy are a significant fraction of the total dose. However, these residuals quickly become unimportant when dating older samples, and this is the age range in which post-IR IRSL dating is likely to be most useful.  相似文献   
103.
本文通过梳理方志等历史文献,认为花木兰故里黄陂说的证据来源早并且多样化,较具可靠性;同时通过对河南虞城说关键证据的辩驳,认为虞城不可能是木兰故里。  相似文献   
104.
技术学习与创新:经济地理学的视角   总被引:4,自引:0,他引:4  
苗长虹  魏也华 《人文地理》2007,22(5):《人文地理》-1-9,18
技术学习与创新是20世纪90年代以来经济地理学研究的核心领域之一,它与"异端经济学"之间的互动,既促进了经济地理学的繁荣和学科地位的提升,也为"异端经济学"对技术学习与创新的研究提供了独特的地理视角。本文试图全面梳理经济地理学技术学习与创新研究兴起与深化的过程,从地理接近与面对面交流,关系接近与实践社区,制度接近、嵌入、路径依赖与创新场三个既相互争论又高度互补的方面,来系统阐述技术学习与创新的经济地理机制,并针对当前研究的局限性提出了建构高层次综合的技术学习创新与区域发展理论的设想。  相似文献   
105.
20世纪90年代以来,跨国公司地方嵌入研究相对聚焦于资本密集型或技术密集型企业,而需要大量非熟练工人的劳动密集型跨国企业并未引起足够关注,建立在产业联系、技术外溢、社会网络等核心概念基础上的跨国公司地方嵌入分析框架很显然不能很好地解释劳动密集型跨国公司地方嵌入的理论与实践问题。在劳工地理学、新经济地理学等学科背景下,基于全球生产网络、关系嵌入、空间修复等核心概念,研究分别从劳工能动性的空间尺度、跨国公司地方嵌入的劳工要素、劳工管控对跨国公司的地方嵌入、区域劳工景观的空间修复等视角出发,系统梳理相关研究进展并提出未来主要研究议题,包括如何识别劳工供需因素对跨国公司地方嵌入的影响机制,如何剖析特殊劳工管控体制下劳工空间实践与能动性的关系,如何刻画跨国公司地方嵌入对区域劳工经济地理景观的影响,如何总结跨国公司地方嵌入与区域发展的战略耦合模式等。  相似文献   
106.
苏巴什佛寺曾是古代丝绸之路上连接中外的重要节点,对其出土遗物的研究为分析丝绸之路上中外文化的交流与融合、贸易的流通与繁荣提供重要借鉴。本工作采用X光照相、X射线荧光、超景深三维视频显微观察、X射线衍射、扫描电镜等科技分析手段,并结合相关文献,对苏巴什佛寺发现的两枚金属制品的功能进行了深入探讨,初步确定一枚样品为西突厥打戳铜币,一枚样品为仿银金属制品,表面使用了自然铝。文章的分析结果对于研究隋唐时期丝绸之路上西域诸国间的经济文化交流,以及中原与西方诸国的经济文化交流提供了重要的参考。  相似文献   
107.
Though present before the Last Glacial Maximum, microblade technology is uncommon in the lithic assemblages of north-central China until the onset of the Younger Dryas (12,900–11,600 calBP). While it is clear that microblades here and elsewhere were connected with mobile adaptations organized around hunting, the attendant assumption that they served primarily in hunting weaponry is not. The archaeological record of north-central China, including excavations at Pigeon Mountain (QG3) and Shuidonggou Locality 12 (SDG 12) in Ningxia Autonomous Region, and Dadiwan in Gansu Providence, and a handful of bone/antler tools slotted for microblade inserts, indicate a more direct linkage to mobility. These data suggest the rise of microblade technology in Younger Dryas north-central China was mainly the result of microblades used as insets in composite knives needed for production of sophisticated cold weather clothing needed for a winter mobile hunting adaptation akin to the residentially mobile pattern Binford termed “serial specialist.” Limited time and opportunities compressed this production into a very narrow seasonal window, putting a premium on highly streamlined routines to which microblade technology was especially well-suited.  相似文献   
108.
全球化和区域竞争引发了广泛的城市合作实践。城市合作是特定地域空间中城市共生演化的动态过程,城市合作的形成与发展,是多种行为主体在多种环境因素和历史因素作用下互动博弈的结果。以新近兴起的演化经济学和演化经济地理学为基础,建构了一个城市合作研究的演化分析框架,探讨了城市合作的本质和内容,分析了我国城市合作模式的类别、演化过程和不同模式的有效性。城市合作的本质在于追求包括分享、匹配和学习三大效应的更高层级的集聚经济,演化理论可以为研究城市群的演化过程,探索适合我国国情和区域发展实际的城市合作模式。  相似文献   
109.
This paper investigates the industrialization of biomedical materials at the New England Enzyme Center (NEEC) from its establishment as a federally supported biochemical resource center in 1964 through its demise and refashioning into several commercial biotech companies in the late 1970s. It sets this history within the long‐standing debate on the proper relation between science and American economic and political traditions. The NEEC sought to embody two aims that stood in tension: academic independence in knowledge production and the market‐driven interests of the biomedical industry. A clash of values ensued, but built on a particular notion of independence: scientists pragmatically accepted the primacy of the market in the age of the ‘federal research economy.’ The question became how to carve out a space for science and scientific values in the market – an intellectual position that some legal and economic scholars have referred to as a scientific commons. Even so, industry executives came to see the idea of a scientific commons and public knowledge as obstructive to industrial innovation. This paper argues that, as seen through the case of the NEEC, the ascendancy of market values and attitudes in the 1970s played a critical role in reconfiguring the science‐industry relationship and in ‘industrializing’ the life sciences. As illustration of this change, I look at a commercial firm – Genzyme – born out of NEEC’s dissolution.  相似文献   
110.
论文依据对青田县方山、船寮等地华侨村官以及所管辖的村民进行田野调查的结果,分析了华侨村官群体出现的原因、作用和特点,剖析了华侨村官工作中存在的阻碍和不足,以及工作中“水土不服”现象和阻碍的因素,旨在为地方政府研究制订华侨参政长效机制提供参考,并以期社会对华侨参政这一新现象给予更多的关注和思考。  相似文献   
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