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Xiao Qiao 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):469-475
QIAO, X., SHIH, C.K. & REN, D., December 2012. Two new Middle Jurassic species of orthophlebiids (Insecta: Mecoptera) from Inner Mongolia, China. Alcheringa 36, 467–472. ISSN 0311-5518. Two new species of the extinct family Orthophlebiidae, Orthophlebia nervulosa sp. nov. and Orthophlebia stigmosa sp. nov., are described and illustrated. These well-preserved specimens were collected from the Middle Jurassic Jiulongshan Formation near Daohugou Village, Inner Mongolia, China. Morphological characters shown in these well-preserved specimens highlight the diversity of orthophlebiids during the Middle Jurassic and provide data for future phylogenetic studies of orthophlebiids. 相似文献
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Testing the standardized growth curve (SGC) to OSL dating coastal sediments from the south Bohai Sea, China 总被引:2,自引:0,他引:2
Guang-Quan Chen Liang Yi Xing-Yong Xu Hong-Jun Yu Jian-Rong Cao Qiao Su Lin-Hai Yang Yong-Hang Xu Jun-Yi Ge Zhong-Ping Lai 《Geochronometria》2013,40(2):101-112
It has been suggested that the standardized growth curve (SGC) method can be used to accurately determinate equivalent dose (De) and reduce measurement time. However, different opinions regarding the applicability of the SGC method exist. In this paper, we evaluated quartz OSL SGCs of marine and coastal sediments of different grain sizes and different cores in the south Bohai Sea in China, and tested their applicability to the determination of De values. Our results suggested as follows: (1) The SGC method is applicable to both multiple- and single-aliquot regenerative-dose (MAR and SAR) protocols of OSL dating and efficiently provides reliable estimates of De. (2) Finesand quartz of different palaeodoses showed highly similar dose-response curves and an SGC was developed, but old samples using the SGC method have large uncertainties. (3) For coarse-silt quartz, two different types of dose-response curves were recorded: low-dose (≤60Gy) and high-dose (≥100Gy). The growth curves of low-dose quartz were similar to each other, facilitating the use of SGC in De estimations, but errors tended to be larger than those obtained in the SAR method. For high-dose (100–300Gy) quartz, the SGC was also found to be reliable, but there was large uncertainty in De (>300Gy) estimation. We suggest that SGC could be employed for the dating of marine and coastal sediments dating using either MAR or SAR OSL protocol and either fine-silt, coarse-silt or fine-sand quartz. 相似文献
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学术界对“A型曲柄短剑”的认识尚且模糊,以至于对其命名、功能及使用方式的看法存在一定的差异。作者通过对其进行细致的形制观察和出土状态分析。以及与西南夷系统和中原系统青铜短剑的比较研究,初步认为“A型曲柄短剑”是作为剑的复合型器物,即具有剑、戈、刀等多种功能和使用方式。 相似文献
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20世纪五六十年代的新方志编纂应认真总结经验、教训.就当时修志的背景、规模、进程,尤其是从成书的数量和质量看,不宜称为"第一轮修志",可以称之为一个序幕或者一次兴起. 相似文献
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新中国土地改革后新富农产生的规模与分布研究 总被引:1,自引:0,他引:1
从土地改革结束到农业集体化高潮前夕,新富农的出现从全国范围来看是稀少而缓慢的。在各省之间,农民的富裕程度与新富农比重大小关系不明显,但在同一地区内来看,两者呈现正相关关系。同时,在农业合作化程度较高亦即是较早对新富农采取限制政策的地区,新富农的比重并不一定低于甚至高于其他地区。这说明多种因素对新富农的产生、发展发生作用,单因素的分析不能解释清楚新富农这个复杂的社会经济问题。 相似文献
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中共建党与近代上海社会 总被引:1,自引:0,他引:1
1921年7月,中共一大在上海召开。作为工业化、现代化和国际化都市的上海,为中共成立提供了最适宜的地理环境。以上海工人为主体的中国工人阶级的壮大和阶级觉悟的提高,为共产党的创建奠定阶级基础。上海发达的媒介网络为马克思主义的早期传播提供便利条件。伴随新文化运动的勃兴,上海成为先进知识分子的集聚与活动中心。以陈独秀为核心的《新青年》编辑部和马克思主义研究会则为中共上海发起组提供基本成员,上海发起组实际担当了组建中共的临时中央。中共在上海的成立是上海近代化的结果。共产党的成立及其初期的活动,构成上海近代史的华章。 相似文献
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Enrique Suárez-Iñiguez 《Perspectives on Political Science》2013,42(1):31-35
Abstract Through a critical consideration of recent proposals urging the use of “citizen forums” or “mini-publics” on issues involving science, this article reflects on the challenge posed to democracy and democratic decision making by the intellectual authority of modern science. Though the danger of a descent into technocracy is real and pressing, arguably the most serious challenge to democracy today, these novel “deliberative democratic” institutions are unpromising as a corrective beyond the local level, and may actually exacerbate the problem. The article concludes with a consideration of alternatives. 相似文献
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