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Zhiguo Rao Haichun Guo Jiantao Cao Fuxi Shi Guodong Jia Yunxia Li Fahu Chen 《第四纪科学杂志》2020,35(8):1036-1045
Recent results indicate contrasting Holocene moisture histories at different elevations in arid central Asia (ACA). However, relatively little is known about Holocene temperature changes at different elevations. Here we report an independently dated peat brGDGTs-based MBT'5ME record from the Narenxia peatland (NRX) in the southern Altai Mountains. The record suggests a long-term warming trend since ~7.7 cal. kyr bp , with a warmer stage during ~7–5.5 cal. kyr bp , a cold stage during ~5.5–4 cal. kyr bp , and a warming trend over the last ~4 kyr. The long-term warming trend indicated by the NRX MBT'5ME record is largely consistent with Holocene temperature records from nearby sites covering an altitudinal range of ~1700–4100 m above sea level. This consistent long-term warming trend at different elevations differs from the long-term Holocene drying/wetting trends at high/low elevations of the Altai Mountains. We propose that the warming trend and consequent permafrost thawing at high elevations could have resulted in increased meltwater runoff, which would have contributed to the long-term wetting trend at low elevations. Our findings potentially provide an improved understanding of regional climate change and associated water resource availability, with implications for their possible future status. 相似文献
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Jianshangou Bed of the Yixian Formation in West Liaoning,China 总被引:4,自引:0,他引:4
CHEN Peiji WANG Qifei ZHANG Haichun CAO Meizhen LI Wenben WU Shunqing & SHEN Yanbin . Nanjing Institute of Geology Palaeontolgoy Chinese Academy of Sciences Nanjing China . State Key Laboratory of Palaeobiology Stratigraphy Nanjing China 《中国科学D辑(英文版)》2005,48(3):298-312
The Jianshangou fossil locality was first found byChang Zhenglu and his colleagures in 1962, now thearea of Jianshangou, Sihetun and Huangbanjigou be-comes famous all over the world for its yielding feath-ered dinosaurs, Confuciusornis and Archaefructus. Thename of Jianshangou Bed was proposed by the firstauthor of present paper as an informal suggesting unitduring the research on Jehol fossils of western Liaon-ing in 1963 and 1964. The unit was named then asJianshan Bed[1], indicating th… 相似文献
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采用惰性气体保护下的高温熔融反应及氮淬冷技术,制备了xLI2S·(1—X)B2O23玻璃。利用DSC量热法研究了玻璃的非等温晶化动力学,计算得到晶化活化能E,Avrami指数n及晶化热—△H等动力学参数。实验发现,xLi2S·(1—X)B2O3硫氧化物能在X≤0.45的区域形成玻璃,x=0.25玻璃组份具有最强的抗晶化能力,而x=0.45玻璃组份最易晶化。玻璃的晶化为一热激活过程,且主要由表面成核机理控制。玻璃晶化活化能在180—100μm颗粒范围有最大值,晶化热—△H与峰值温度Tp满足线性关系。 相似文献
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Qi Zhang Alexandr P. Rasnitsyn Bo Wang Haichun Zhang 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(6):736-747
The Burmese amber assemblage of Hymenoptera with its 47 constituent families is now the richest in Cretaceous. A collection of Burmite (Burmese amber) from the Hukawng Valley, Myanmar at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences was examined, revealing that Burmite inclusions contain a very highly diverse hymenopteran fauna with as many as ten families found new for the Burmese fossil assemblage. The mid-Cretaceous hymenopteran fauna of Burmese amber is revised at the family level. A high level of the first family occurrences and endemism is demonstrated suggestive of an insular syndrome affected the mid-Cretaceous Burmese biome, as well as somewhat contradictory features in composition of the hymenopteran families there. 相似文献
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