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391.
铜同位素分析法在考古研究中的应用探讨   总被引:1,自引:0,他引:1       下载免费PDF全文
最新地球化学研究发现,自然界不同地质条件和成矿环境中的铜同位素组成存在显著差异。根据铜矿中铜同位素变化规律,考古学家已将铜同位素作为一种新的示踪剂应用于考古探源研究之中。文章介绍了铜同位素地球化学的最新发展、考古应用原理、实验方法及相关的考古应用实例。认为尽管自然界铜同位素的变化较为复杂且铜同位素地球化学还处于形成发展阶段,但铜同位素分析法在含铜器物的产地研究中已显示出了较好的应用前景。随着铜同位素地球化学研究的深入及分析技术的进一步提高,铜同位素分析法将会在考古研究中发挥更大的作用。  相似文献   
392.
There are more than thirty iron hammerheads known from the pre-Roman Iron Age in Britain, the majority of which are assigned to the first centuries BC and AD. They include specialised tools, such as set hammers and a swage sledge-hammer which are blacksmiths' tools. The hand-hammers are more numerous and many of these are probably also metalworkers' tools. Fourteen have been examined by metallography showing that at least ten are quench hardened at one or both faces and some may have been tempered.  相似文献   
393.
试论清政府镇压太平天国后的让步政策   总被引:1,自引:0,他引:1  
"让步政策"的讨论已有半个多世纪的历史,"文革"后,"让步政策"论为大多数史学工作者所接受,而认为近代没有"让步政策"却似乎已成定论.作者通过清政府在镇压太平天国后实行的减浮、减赋、减差、招垦、劝农桑、兴水利等减轻农民负担,稳定社会秩序,恢复和发展农业生产的措施,认定近代确有"让步政策",而清政府的"让步政策",确实让农民得到了经济实惠,促进了经济的发展.  相似文献   
394.
395.
用溴氰除虫菊酯对飞天藏上的木雕人像进行杀虫。使用1:1CWT5-1型SCC填充剂(丙烯酸酯乳液:水=1:1)。进行加固处理。处理后,纵波速度按木材质地的不同,分别从处理前的417m/s(松)、643m/s(柏)、678m/s(楠),提高到843m/s(松)、1146m/s(柏)、1184m/s(楠),且外观无明显的变化。  相似文献   
396.
郑锦  刘辉雄 《福建史志》2020,(2):18-21,25
年鉴常规性条目普遍存在,而互联网时代的碎片化阅读、浅阅读习惯以及年鉴检索功能的强化,使得一些常规性条目被"隐身"。年鉴的常规性条目由来已久、客观存在,年鉴学派的"长时段"理论,也说明常规性条目是年鉴的必然存在。传承历史需要常规性条目,从发展角度看也需要常规性条目。编好常规性条目,应从技术、学术、艺术等方面增强常规性条目的索引功能,使之"重生",实现条目设置的健康化、立体化,担当起"编志为用"的时代使命。  相似文献   
397.
本文通过对西周至春秋时期见于史载的楚国的封地和采邑的梳理,认为在西周至春秋中前期,楚国的采邑制发展一直较为缓慢,而在春秋中后期,由于不同楚王所施行政策的差异,造成了楚国地方政治体制的剧烈变动,采邑数量因此显著增多,并表现出新的发展趋势和特点.  相似文献   
398.
Zheng, D., Nel, A., Jarzembowski, E.A., Chang, S.-C., Zhang, H. & Wang, B., May 2018. Exceptionally well-preserved dragonflies (Insecta: Odonata) in Mexican amber. Alcheringa xxx, xxx–xxx.

Dragonflies (odonatans) are comparatively rare as amber inclusions, and most are not well preserved on account of their size. Here, we report a single piece of Mexican amber with one complete dragonfly and two damselflies. The dragonfly is attributed to the extant gomphid Erpetogomphus Selys Longchamps, and the damselflies belong to the extant coenagrionid Argia Rambur. Both genera are nowadays distributed widely in Mexico. The new discovery dates the origins of these two genera to the Miocene at least.

Daran Zheng [], Edmund A. Jarzembowski* [] Haichun Zhang [] and 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; Daran Zheng, Su-Chin Chang [] Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, 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. Received 23.1.2018; revised 6.3.2018; accepted 20.3.2018.  相似文献   

399.
Zheng, D. &; Wang, B., November, 2018. The second hemiphlebiid damselfly (Odonata: Zygoptera) from mid-Cretaceous Burmese amber. Alcheringa 43, 257–260. ISSN 0311-5518.

Burmahemiphlebia zhangi Zheng et al., 2017 Zheng, D., Zhang, Q., Nel, A., Jarzembowski, E.A., Zhou, Z., Chang, S.-C. &; Wang, B., 2017. New damselflies (Odonata: Zygoptera: Hemiphlebiidae, Dysagrionidae) from mid-Cretaceous Burmese amber. Alcheringa 41, 1221.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar] is the dominant damselfly found in Burmese amber. Here, a new hemiphlebiid damselfly, Burmahemiphlebia hui sp. nov., is described representing the second Burmahemiphlebia species discovered in Burmese amber. Burmahemiphlebia hui sp. nov. differs from Burmahemiphlebia zhangi in having more postnodal cross-veins, CuP and the separating point of AA from AP basal of A?×?1, Arc aligned with A?×?2, RP2 base closer to N than to Pt, and IR1 five cells distal of RP2 base. The new damselfly is extremely rare and the only one known from Burmese amber, unlike Burmahemiphlebia zhangi.

Daran Zheng* [], Bo Wang? [] State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China. *Also affiliated with: Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China. ?Also affiliated with: Shandong Provincial Key Laboratory of Depositional Mineralization &; Sedimentary Minerals, Shandong University of Science and Technology, Qingdao, Shandong 266590, PR China and Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.  相似文献   
400.
Zheng, Y., Chen, J., Zhang, J. & Zhang, H., 6 August 2019. New fossil sawflies (Hymenoptera, Xyelidae) from the Middle Jurassic of northeastern China. Alcheringa 44, 115–120. ISSN 0311-5518.

Magnaxyela rara gen. et sp. nov. and Abrotoxyela curva sp. nov. (Xyelidae, Macroxyelinae, Gigantoxyelini) are described from the Middle Jurassic Jiulongshan Formation at Daohugou Village, Inner Mongolia, China. The two new species are confidently assigned to tribe Gigantoxyelini of subfamily Marcroxyelinae based on their wing venation and various other morphological characters. Magnaxyela rara is established based on the following forewing characters: pterostigma sclerotized completely, Sc two-branched and meeting R before origin of Rs, 1-Rs as long as 1-M, but shorter than Rs?+?M, R curved bewteen 1r-rs and 2r-rs and cell 2r longer than 1r. Abrotoxyela curva is differentiated from congeneric forms by the two-branched vein Sc of the forewing, Sc2 short and inclined towards the base of the wing, 1-Rs, 1-M and Rs?+?M nearly equal in length, crossvein 1m-cu longer than 1cu-a. The fossils described herein increase the diversity of the Mesozoic Xyelidae.

Yan Zheng* [], Jun Chen* [], and Junqiang Zhang [], Institute of Geology and Paleontology, Linyi University, Shuangling Road, Linyi 276000, PR China; Haichun Zhang [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, East Beijing Road, Nanjing 210008, PR China. *Also affiliated with: State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, East Beijing Road, Nanjing 210008, PR China.  相似文献   
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