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Statistical analysis and model of spread F occurrence in china

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Science china(Technological Sciences) 2010年第6期53卷 1725-1731页

作者： XU Tong1,WU ZhenSen2,HU YanLi1,WU Jian1,SUO YuCheng1 & FENG Jian1 1 national key laboratory of electromagnetic environment,china Research Institute of Radiowave Propagation,qingdao 266107,china 2 School of Science,Xidian University,Xi’an 710071,china 1. national key laboratory of electromagnetic environment China Research Institute of Radiowave Propagation Qingdao 266107 China2. School of Science Xidian University Xi’an 710071 China

The spread F data obtained over Lanzhou (36.1°N,103.9°E),Chongqing (29.5°N,106.4°E) and Haikou (20.0°N,110.3°E) of china during the period from 1978 to 1997 are used to analyze the occurrence *** statistical results show that the post midnight spread F occurrence is maximum during the summer solstice months of the lower solar activity period,while post sunset spread F is dominant in equinoxes of higher solar activity period over Haikou *** Chongqing and Lanzhou stations,spread F mostly occurs at post midnight and relates negatively with solar *** regression method and Fourier expansion,the preliminary single-station model of spread F occurrence is established and the accuracy of the model is evaluated.

关键词： spread F solar cycle variation seasonal variation empirical model

Genesis of ^(230)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science china Earth Sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1,2 & ZENG ZhiGang1 1 key laboratory of Marine Geology and environment,Institute of Oceanology,Chinese Academy of Sciences,qingdao 266071,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 1. key laboratory of Marine Geology and environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on 230Th-238U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 230Th excess.(230Th/238U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 230Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(230Th/238U) in OIBs actually corresponds to a lower melting *** suggests that the 230Th excess in MORBs is controlled by mantle melting conditions,while the 230Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 230Th are between 1.0 and 2.5 GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2-3.5 GPa(around the spinel-garnet transition zone),with their low excess 226Ra compared to MORBs also suggesting a deeper mantle ***,excess 230Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2O/TiO2 with(230Th/238U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 230Th does not tap the spinel-garnet transition *** and MORBs in both(230Th/238U) vs.K2O/TiO2 and(230Th/238U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 230Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 230Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island

Sediment transport capacity of hyperconcentrated flow

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 961-975页

作者： SHU AnPing1,2 & FEI XiangJun2 1 School of environment & key laboratory of Water and Sediment Sciences,Ministry of Education,Beijing Normal University,Beijing 100875,china 2 State key laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,china School of environment & key laboratory of Water and Sediment Sciences Ministry of Education Beijing Normal University Beijing 100875 China State key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

关键词： hyperconcentrated flow turbulent energy equilibrium efficiency coefficient sediment transport capacity

Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

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Science china Earth Sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2,LIN XueHui1,2,YAO De3,4 & GUO WeiDong5 1 key laboratory of Marine Oil and Gas Resources and Marine environment,Ministry of Land and Resources,qingdao 266071,china 2 qingdao Institute of Marine Geology,china Geological Survey,qingdao 266071,china 3 Institute of Resources and environment,Shandong University of Technology,Zibo 255049,china 4 Institute of Oceanology,Chinese Academy of Sciences,qingdao 266071,china 5 Department of Oceanography,Xiamen University,Xiamen 361005,china 1. key laboratory of Marine Oil and Gas Resources and Marine environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

Analysis of the contribution of acid phosphatase to P efficiency in Brassica napus under low phosphorus conditions

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Science china(Life Sciences) 2010年第6期53卷 709-717页

作者： ZHANG HaiWei1,2,HUANG Yu2,YE XiangSheng2 & XU FangSen1,2 1 national key laboratory of Crop Genetic Improvement,Huazhong Agricultural University,Wuhan 430070,china 2 key laboratory of Subtropical Agriculture and environment,Ministry of Agriculture,Huazhong Agricultural University,Wuhan 430070,china 1. national key laboratory of Crop Genetic Improvement Huazhong Agricultural University Wuhan 430070 China2. Key Laboratory of Subtropical Agriculture and Environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 China

To understand whether genotypic variation in acid phosphatase (APase) activity in rapeseed (Brassica napus L.) induced by phosphorus (P) deficiency has impact on P efficiency,soil APase activity in the rhizosphere for rapeseed P-efficient genotype 102 and P-inefficient genotype 105 was measured against organic and inorganic P sources in the pot experiment,and the activities of root-secreted APase and leaf intracellular APase were investigated in different P-starvation periods in the nutrient *** activity of root-secreted APase in *** was induced under low P ***,P nutrition and P uptake efficiency of the plants supplied with organic P were not directly related to the activity of root-secreted APase due to several confounding factors affecting APase *** higher activity of leaf APase improved P remobilization in plants and played important roles in enhancing P use efficiency,shown by the significant correlation between leaf APase activity and P use efficiency in a rapeseed recombinant inbred population of 135 lines.

关键词： Brassica napus APase activity P remobilization P efficiency low-P stress

Endolithic fungi:A possible killer for the mass extinction of Cretaceous dinosaurs

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Science china Earth Sciences 2008年第6期51卷 801-807页

作者： GONG YiMing1,2, XU Ran1 & HU Bi2 1 key laboratory of Biogeology and environmental Geology of Ministry of Education, State key laboratory of Geological Processes and Mineral Resources, china University of Geosciences, Wuhan 430074, china 2 Institute of Resources and environment key laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province, Henan Polytechnic University, Jiaozuo 454003, china 1. key laboratory of Biogeology and environmental Geology of Ministry of Education State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. Institute of Resources and environment key laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province Henan Polytechnic University Jiaozuo 454003 China

Mycelium-like structures found under ESEM within radial sections of fragmental dinosaur eggshells would be the endolithic fungi coexistent with dinosaur eggs in the upper part of the Late Cretaceous Hugang Formation from the Wenjiaping section of Wenxian, Danjiangkou, northwestern Hubei, Central china. The endolithic fungi selectively occurred in the bad biomineral zone within the columnar layer of the eggshells, where the crowded endolithic fungi penetrated the columnar layer at near-vertical or near-horizontal angles. The endolithic fungi are needle-like, ribbon-like and silk-like, and 5–18 μm long, 0.3–0.5 μm wide at their base, with pointed tip, and are unbranched. The hyphae are mainly composed of oxygen, carbon and calcium, and are with minor sodium, potassium, chlorine and sulfur. The endolithic fungi and host have the same characters in lithification, fracture and main chemical composition. We suggested that the episode endolithic fungi invading dinosaur eggs may have taken place in the interval between after formation of dinosaur eggshells and before their petrification and that dinosaur eggs invaded by endolithic fungi would not be normally incubated or would only be incubated into venerable and pathologic baby dinosaurs to be easily to aborted and contributed to the mass extinction of the dinosaurs at the end of Cretaceous.

关键词： endolithic fungi dinosaur eggs mass extinction Cretaceous

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2, TAN Zhi-xiang1, 2, DENG Ka-zhong1, 2 1. key laboratory for Land environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china University of Mining and Technology, Xuzhou 221116, china 2. Jiangsu key laboratory of Resources and environmental Information Engineering, china University of Mining and Technology, Xuzhou 221116, china [a] key laboratory for Land environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu key laboratory of Resources and environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2π] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

ULTRASONIC SEPARATION OF MICRO-SIZED INCLUSIONS IN MOLTEN METAL

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Acta Metallurgica Sinica(English Letters) 2001年第5期14卷 375-379页

作者： X.Q. Bai and J.C. He key laboratory of national Education Ministry for electromagnetic Processing of Materials, Northeastern University, Shenyang 110004, china key laboratory of national Education Ministry for electromagnetic Processing of Materials Northeastern University

The coagulation time and position of micro-sized non-metallic inclusions in molten metal during ultrasonic separation process were investigated, and the motion course of micro-sized non-metallic inclusions in an ultrasonic standing wave field was numerically simulated. The results of theoretical analysis and numerical simulation show that the movement of inclusions depends on the balance between the acoustic radiation force, effective buoyancy force and viscous drag force. It is presented that micro-sized inclusions, agglomerated at antinode-planes may be removed further with horizon tal ultrasound.``

关键词： ultrasound molten metal micro-sized non-metallic inclusion numerical simulation process parameter

A new method for mining deformation monitoring with GPS-RTK

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中国有色金属学会会刊：英文版 2011年第S3期21卷 659-664页

作者： GAO Jing-xiang1, 2, LIU Chao2, WANG Jian1, 2, LI Zeng-ke2, MENG Xiang-chao2 1. key laboratory for Land environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china University of Mining and Technology, Xuzhou 221116, china 2. School of environment and Spatial Informatics, china University of Mining and Technology, Xuzhou 221116, china [a] key laboratory for Land environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] School of environment and Spatial Informatics China University of Mining and Technology Xuzhou 221116 China

Based on ranging intersection theory, a new method which is simple and easy to operate was proposed for data collection in the mine surface deformation monitoring with GPS-RTK centering rod measurements. It can fully eliminate the inevitable shaking error and the vertical deflection, and to some extent weaken the multipath effect on the estimates of coordinates in a relatively short period of time, using high-frequency observations. The results show that three-dimensional coordinates with a height accuracy better than 1 cm, horizontal accuracy better than 2-4 cm can be achieved through only 15-30 s continuous observation by 20 Hz high-frequency and effectively improve the measurement accuracy and efficiency of RTK, fully satisfying the high-speed and high-precision data acquisition in mine surface subsidence deformation monitoring.

关键词： GPS rover pole multipath delay deformation monitoring