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Chinese Science Bulletin 2005年第17期50卷 1940-1948页

作者： HUANG Chunming1,2. ZHANG Shaodong1,2.& YI Fan1,2.1. School of Electronic Information, wuhan Universiy, wuhan 43.079, China {2., ministry of education, wuhan university, wuhan 43.079, China School of Electronic Information Wuhan Universiy Wuhan China key laboratory of {2. {2. and geodesy Ministry of Education Wuhan University Wuhan China

By using a three-dimensional fully nonlinear numerical model in spherical coordinates and taking the linear steady solutions of the migrating diurnal and semidi-urnal tides in January from the Global-Scale Wave Model (GSWM) as the initial values, we simulate the linear and nonlinear propagations of the migrating diurnal and semidi-urnal tides in the atmosphere from the ground to the lower thermosphere. A comparison of our simulations with the results of GSWM is also presented. The simulation results show that affected by the nonlinearity, the migrating diurnal and semidiurnal tides propagating in the middle and upper atmosphere exhibit evident short-term variability. The nonlinear interactions between the migrating tides and the background atmosphere can obviously alter the background wind and temperature fields, which suggests that the nonlin-ear propagations of the migrating diurnal and semidiurnal tides impact significantly on the transient dynamical and thermal structures of the background middle and upper at-mosphere and the nonlinear effect is an important cause of the difference between the results of GSWM and observa-tions.

关键词：大气非线性传播数学模型可变性温度场

Estimation on principal component of multi-collinearity Gauss-Markov model based on minimum description length

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中国有色金属学会会刊：英文版 2005年第S1期15卷 153-155页

作者： SHI Yu-feng~(1, 2. (1. Shandong university of Technology, Zibo 2.5049, China 2. key laboratory of geospace environment and geodesy,{2., wuhan university, wuhan 43.079, China) Shandong Univ Technol Zibo 255049 Peoples R China wuhan Univ Minist Educ Key Lab Geospace Environm & Geodesy Wuhan 430079 Peoples R China

Gauss-Markov model is frequently used in data analysis; the analysis and estimation of its parameters is always a hot issue. Based on the information theory and from the viewpoint of optimal information on description—minimum description length, this paper discusses a case: where there is multi-collinearity in the coefficient matrix, principal component estimation is used to estimate and select the original parameters, so as to reduce its multi-collinearity and improve its credibility. From the viewpoint of minimum description length, this paper discusses the approach of selecting principal components and uses this approach to solve a practical problem.

关键词： minimum description length Gauss-Markov model multi-collinearity principal component estimation

Numerical study of the auroral particle transport in the polar upper atmosphere

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Science China(Technological Sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2. MA ShuYing1,2.& PU ZuYin3 1 School of Electronic Information, wuhan university, wuhan 43.079, China 2.{2. {2. of geospace environment and geodesy, ministry of education of PRC, wuhan 43.079, China 3 School of Earth and Space Sciences, Peking university, Beijing 100871, China School of Electronic Information Wuhan University Wuhan China key laboratory of {2. {2. and geodesy Ministry of Education of PRC Wuhan China School of Earth and Space Sciences Peking University Beijing China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2., to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2.ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

GRACE detection of the medium-to far-field coseismic gravity changes caused by the 2.04 Mw9.3 Sumatra-Andaman earthquake

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Earthquake Science 2012年第3期25卷 235-240页

作者： Jin Li1,2.3 and Wenbin Shen1,3,4, 1 Department of Geophysics, School of geodesy and Geomatics, wuhan university,{2., China 2.key laboratory of Geodynamic geodesy of Chinese Academy, wuhan 430077, China 3 key laboratory of geospace environment and geodesy ({12. of education), wuhan university,{2., China 4 State key laboratory of Information Engineering in Surveying, Mapping and Remote Sensing,{2., China Department of Geophysics School of Geodesy and Geomatics Wuhan University Wuhan China key laboratory of Geodynamic {2. of Chinese Academy Wuhan China key laboratory of {2. {2. and geodesy (ministry of education) Wuhan University Wuhan China State key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan China

Large earthquakes cause observable changes in the Earth’s gravity field, which have been detected by the Gravity Recovery and Climate Experiment (GRACE). Since most previous studies focus on the detection of near-field gravity effects, this study provides the results from the medium- to far-field gravity changes caused by the 2.04 Sumatra-Andaman earthquake that are recorded within GRACE monthly solutions. Utilizing a spherical-earth dislocation model we documented that large-scale signals predominate in the global field of the coseismic gravity changes caused by the earthquake. After removing the near-field effects, the coseismic gravity changes show a negative anomaly feature with an average magnitude of -0.18×10-8 m·s-2.in the region ranging ～40° from the epicenter, which is considered as the 'medium ffield' in this study. From the GRACE data released by Center for Space Research from August 2.02.to December 2.08, we retrieved the large-scale gravity changes smoothed with 3 000 km Gaussian ffilter. The results show that the coseismic gravity changes detected by GRACE in the medium field have an average of (-0.2.±0.06)×10-8 m·s-2. which agrees with the model prediction. The detection confirms that GRACE is sensitive to large-scale medium-field coseismic gravitational effects of mega earthquakes, and also validates the spherical-earth dislocation model in the medium field from the perspective of satellite gravimetry.

关键词： GRACE medium-to far-field coseismic gravity change 2.04 Sumatra-Andaman earthquake spherical-Earth dislocation model

SATELLITE GRAVITY SURVEYING TECHNOLOGY AND RESEARCH OF EARTH’S GRAVITY FIELD

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大地测量与地球动力学 2003年第B12期23卷 1-7页

作者： Ning Jinsheng (The key laboratory of Geo Space {2. and {2., ministry of education, wuhan university, wuhan 43.079, China) The key laboratory of Geo-Space {2. and {2. Ministry of EducationWuhan University Wuhan 430079 China

This is a summarized paper. Two topics are discussed: Firstly, the concept, development and application of four kinds of satellite gravity surveying technology are introduced; Secondly, some problems of theory and method, which must be considered in the study of the \{Earth’s\} gravity field based on satellite gravity data, are expounded.

关键词：卫星重力测量技术地球重力场卫星轨道技术概念技术进展技术应用空中重力测量

Ce Anomalies of the Yangtze Region,South China,through the Ordovician and Silurian Transition

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Journal of Earth Science 2009年第6期20卷 941-948页

作者：严德天张丽琴李双建 key laboratory of Tectonics and Petroleum Resources of{2. China University of GeosciencesWuhan Institute of Geology and Geophysics Chinese Academy of Sciences School of geodesy and Geomatics Wuhan University key laboratory of {2. {2. & geodesy of ministry of education Wuhan University Petroleum Exploration and Production Institute of SINOPEC

Systematic Ce anomalies for whole-rock have been obtained from the shale-dominated, continuous, and pelagic sedimentary sequences spanning the Ordovician/Silurian （O/S） boundary at the Tieshui （铁水） of Xiushan （秀山）, Chongqing （重庆）, South China. Ce anomalies across the O/S boundary are recognized in three intervals, Wufeng （五峰）, Guanyinqiao （观音桥） and Longmaxi （龙马溪）. The calculated Ce/Ce＊ values of Wufeng Formation range from 0.84 to 0.96 （avg. 0.90）. In the Guanyinqiao Formation, the values of calculated Ce/Ce＊ range from 0.73 to 0.85 （avg. 0.79）. The Ce/Ce＊ values of uppermost Longmaxi Formation range from 0.87 to 0.96 （avg. 0.91）. All along the section, the magnitude of the Ce anomaly is always negative, but is more significant in the Guanyinqiao Formation. The relatively higher Ce/Ce＊ values in the Wufeng and Longmaxi shales are likely to be due to the sediments deposited under rather reducing conditions. The Ce anomaly apparently does play some regular roles in the anoxic events that accompany prominent mass extinctions, and this work provides new data of critical importance for constraining models on the end-Ordovician anoxic events and mass extinctions.

关键词： Ce anomaly redox mass extinction Ordovician/Silurian boundary Yangtze platform.

Sedimentary geochemistry of the Cambrian-Ordovician cherts: Implication on archipelagic ocean of North Qilian orogenic belt

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Science China Earth Sciences 2007年第11期50卷 1628-1644页

作者： DU YuanSheng1,2. ZHU Jie1, GU SongZhu1, 2. XU YaJun1 & YANG JiangHai1 1 Faculty of Earth Sciences, China university of Geosciences, wuhan 430074, China 2.{2. {2. of Biogeology and environment Geology of education ministry, wuhan 430074, China Faculty of Earth Sciences China University of Geosciences Wuhan China key laboratory of Biogeology and {2. Geology of {2. ministry Wuhan China

The Caledonian North Qilian orogenic belt lies between the North China plate and the Qaidam mi-croplates, and resulted from the collision among the Qaidam microplate, mid-Qilian block and the North China plate. The orogen initiated from the rifting of the Late Proterozoic Rodinia, and then it experi-enced stages of Cambrian rift basin and Ordovician archipelagic oceanic basin, and foreland basin during Silurian to Early-Middle Devonian. The average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn and Lan/Cen from cherts of Cambrian Heicigou Formation are 0.797, 0.62., 1.114, 0.994 and 1.034 re-spectively. In the NAS standardized REE distribution pattern, the cherts from Xiangqianshan is slightly HREE enriched, and the cherts from Ganluci and Shiqingdong are plane. All of these features indicated that Cambrian cherts of the Heicigou Formation originated from a continental margin rift background. On the contrary, the average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn, Lan/Cen of the Ordovician chert from Dakecha, Cuijiadun, Shihuigou, Laohushan, Heicigou, Maomaoshan, Bianmagou, Da-chadaban, Baiquanmen, Jiugequan and Angzanggou, are respectively 0.72. 0.58, 0.99, 1.09 and 0.96 respectively. Their NAS standardized REE distribution patterns of most Ordovician cherts are plane mode or slightly HREE enriched. The REE distribution pattern of few samples of cherts are slightly LREE enriched. Characteristics of sedimentary geochemistry and tectonic evolution demonstrated that the Cambrian-Ordovician cherts, associated with rift, oceanic, island arc and back-arc volcanic rocks, was not formed in a typical abyssal oceanic basin or mid-oceanic ridge. On the contrary, they formed in a deepwater basin of continental margin or a archipelagic ocean tectonic setting. Several Early Paleo-zoic ophiolite belts in North Qilian and adjacent periphery Qaidam microplate imply that an archipelagic ocean during Ordovician existed in the east of Pro-Tethys.

关键词： North Qilian orogenic belt,Cambrian-Ordovician,cherts sedimentary geochemistry,archipelagic ocean

Atmospheric correction of HJ-1A/B CCD images over Chinese coastal waters using MODIS-Terra aerosol data

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Science China(Technological Sciences) 2010年第S1期53卷 191-195页

作者： TIAN LiQiao 1,LU JianZhong 1,CHEN XiaoLing 1,2.3,YU ZhiFeng 1,XIAO JingJing 1,QIU Feng 1 & ZHAO Xi 1 1 State key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,{2. {2.,{2. 43.079,China 2.0} laboratory of Poyang Lake Wetland and Watershed Research,ministry of education,Jiangxi Normal {2.,Nanchang 33002.,China 3 The key laboratory of Poyang Lake environment and Resource Utilization,ministry of education,Nanchang {2.,Nanchang 330031,China State key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China key laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education Jiangxi Normal University Nanchang China The key laboratory of Poyang Lake {2. and Resource Utilization Ministry of Education Nanchang University Nanchang China

This paper demonstrates an atmospheric correction method to process HJ-1A/B CCD images over Chinese coastal waters with the aid of MODIS-Terra aerosol *** on the assumption of zero water-leaving radiance at the two near-infrared (NIR)bands or the shortwave infrared(SWIR)bands,the atmospheric aerosol optical depth(AOD)is firstly retrieved from MODIS-Terra with a simple extension of the NIR-SWIR combined atmospheric correction approach embedded in SeaDAS (SeaWiFS data analysis system).Then the"turbid"and"non-turbid"waters are separated by the turbid water *** probability of AOD at 551 nm band is derived based on the NIR information over"non-turbid"waters and FLAASH model is selected to do the atmospheric correction of the HJ-1A/B CCD imagery using the AOD values of highest probabilities as ***,according to the histogram of the AOD distribution at 551 nm band,the studied turbid water area is divided into several blocks and HJ-1A/B CCD imagery is corrected with the corresponding AOD values displayed with the highest frequency in each *** method has been applied to several HJ-1A/B images over Chinese coastal waters and validated by synchronous in-situ *** results have shown that this method is effective in the atmospheric correction process of HJ-1A/B CCD images for ocean color remote sensing study and application in the coastal waters.

关键词： ocean color remote sensing atmospheric correction turbid coastal waters HJ-1A/B MODIS

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 {2. of Water and Sediment Sciences,{2. of education,Beijing Normal university,Beijing 100875,China 2.State key {2. of Hydroscience and Engineering,Tsinghua university,Beijing 100084,China School of environment & key {2. of Water and Sediment Sciences Ministry of Education Beijing Normal University Beijing China State key laboratory of Hydroscience and Engineering Tsinghua University Beijing 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

Effects of Cu^(2.) on characteristic of SV currents

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Science China Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1,2.& YANG Pin1 1. key laboratory of Chemical Biology and Molecular Engineering of{2., Institute of Molecular Science, Shanxi {2., Taiyuan 030006, China 2. Institute of environment Science, Taiyuan {2. of Science and Technology, Taiyuan 03002., China key laboratory of Chemical Biology and Molecular Engineering of{2. Institute of Molecular Science Shanxi University Taiyuan China Institute of environment Science Taiyuan University of Science and Technology Taiyuan China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2. on Slow Vacuolar (SV) current’s characteristic. Our results show that Cu2. in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2. significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2.. These results show that there may be some Cu2. binding sites on SV channels and binding to which can change SV current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2., SV channel.