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Multifractal Analysis of Element Distribution in Skarn-type Deposits in the Shizishan Orefield, Tongling Area, Anhui Province, China 总被引:3,自引:1,他引:2
Wang Qingfei Deng Jun Wan Li Zhao Jie Gong Qingjie Yang Liqiang Zhou Lei Zhang Zhijun 《《地质学报》英文版》2008,82(4):896-905
A series of element concentrations sampled from four drill cores with a length about 1000 m into different skarn-type deposits were selected from the Shizishan orefield, central Tongling, southeastern part of Anhui Province. Using the multifractal method, the distribution and migration characteristics of the major and trace elements are analyzed. The multifractal spectrum of the major elements is left-skewed, whereas the spectrum of the trace elements is right-skewed, which shows that in the process of skarn formation, the trace elements were enriched only locally, and major elements transported within a much larger range. The correlation coefficients of the multifractal parameters Aa (width of the multifractal spectrum) of the four drill cores are relatively low, but the correlation coefficients of the multifractal parameters R (spectrum symmetry parameter) and Af are relatively higher, indicating that although the non-homogeneous intensity of the distribution of elements is inconsistent, their spatial accumulation patterns are almost the same during the ore-forming process. The statistics of the mnltifractal parameters of various elements in the different locations show that the ore-forming processes and element migration pattern in the Shizishan orefield are consistent, and that the migrations of trace elements and major elements exhibit some differences. 相似文献
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维生素D(VD)是一类具有抗佝偻病作用的类固醇激素,其中维生素D3(VD3)是VD在动物体内的主要存在形式.作为生命活动必不可少的一类物质,VD发挥着广泛且重要的生理学作用.VD在动物体内的代谢过程及相关的代谢酶具有较高的进化保守性,同时也受到多种因素的调控影响.由于鱼类在生活环境方面与陆生脊椎动物存在显著差异,VD在... 相似文献
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Based on the CINRAD Doppler radar data in Guangzhou and the lightning data in 2004 by power suppliers of Guangdong, statistical study is done by overlaying lightning’s position on radar’s echo. The result shows the followings. The concentrated period in which more negative lightning occurred at the middle levels (2 – 14 km), where radar echo was moderate (12 – 45 dBz), rather than at the low levels with the weakest echoes or at high levels with the strongest echoes. At levels 3 – 11 km, where the radar echo was between 10 dBz and 35 dBz, the area of negative lightning was much larger in central Guangdong than in the rest of the province. At levels 0.5 – 7 km where the radar echoes were between 44 dBz and 51 dBz, the probability for a point to have negative lightning varies from 0.4 to 0.7. 相似文献
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Lijing CHENG John ABRAHAM Kevin ETRENBERTH John FASULLO Tim BOYER Ricardo LOCARNINI Bin ZHANG Fujiang YU Liying WAN Xingrong CHEN Xiangzhou SONG Yulong LIU Michael EMANN Franco RESEGHETTI Simona SIMONCELLI Viktor GOURETSKI Gengxin CHEN Alexey MISHONOV Jim REAGAN Jiang ZHU 《大气科学进展》2021,38(4):523-530
The long-term warming of the ocean is a critical indicator of both the past and present state of the climate system. It also provides insights about the changes to come, owing to the persistence of both decadal variations and secular trends,which the ocean records extremely well(Hansen et al., 2011;IPCC, 2013;Rhein et al., 2013;Trenberth et al., 2016;Abram et al., 2019). 相似文献
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Western North Pacific Tropical Cyclone Database Created by the China Meteorological Administration 总被引:19,自引:0,他引:19
Xiaoqin LU Hui YU Ming YING Bingke ZHAO Shuai ZHANG Limin LIN Lina BAI Rijin WAN 《大气科学进展》2021,38(4):690-699
This paper describes the access to, and the content, characteristics, and potential applications of the tropical cyclone(TC) database that is maintained and actively developed by the China Meteorological Administration, with the aim of facilitating its use in scientific research and operational services. This database records data relating to all TCs that have passed through the western North Pacific(WNP) and South China Sea(SCS) since 1949. TC data collection has expanded over recent decades via continuous TC monitoring using remote sensing and specialized field detection techniques,allowing collation of a multi-source TC database for the WNP and SCS that covers a long period, with wide coverage and many observational elements. This database now comprises a wide variety of information related to TCs, such as historical or real-time locations(i.e., best track and landfall), intensity, dynamic and thermal structures, wind strengths, precipitation amounts, and frequency. This database will support ongoing research into the processes and patterns associated with TC climatic activity and TC forecasting. 相似文献