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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 430079,{2. 2. Key Laboratory of geospace environment and geodesy, ministry of education, wuhan University, wuhan 430079,{2. School of Electronic Information Wuhan University Wuhan 430079 China Key Laboratory of geospace environment and {2. Ministry of Education Wuhan University Wuhan 430079 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

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 430079,{2. 2.Key Laboratory of geospace environment and geodesy, ministry of education of PRC, wuhan 430079,{2. 3 School of Earth and Space Sciences, Peking University, Beijing 100871,{2. 1. School of Electronic Information Wuhan University Wuhan 430079 China 2. Key Laboratory of geospace environment and {2. Ministry of Education of PRC Wuhan 430079 China 3. School of Earth and Space Sciences Peking University Beijing 100871 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

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 2.5.49, china 2. Key Laboratory of geospace {2. and geodesy, ministry of education, wuhan University, wuhan 430079, 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

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 (ministry of education), wuhan University,{2., china 4 State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing,{2., china 1. Department of Geophysics School of Geodesy and Geomatics Wuhan University Wuhan 430079 China 2. Key Laboratory of Geodynamic geodesy of Chinese Academy Wuhan 430077 China 3. Key Laboratory of geospace environment and {2. (ministry of education) Wuhan University Wuhan 430079 China 4. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan 430079 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 environment and geodesy,{2., wuhan University, wuhan 430079,{5.) The Key Laboratory of Geo-Space environment and geodesy 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 ministry of education China University of GeosciencesWuhan Institute of Geology and Geophysics Chinese Academy of Sciences School of geodesy and Geomatics Wuhan University Key Laboratory of geospace environment & {2. 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.

Radiosonde observations of high-latitude planetary waves in the lower atmosphere

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Science china Earth Sciences 2010年第6期53卷 919-932页

作者： WANG Rui1,2.3, ZHANG ShaoDong1,2.3 & YI Fan1,2.3 1 School of Electronic Information, wuhan University, wuhan 430079,{2. 2.Key Laboratory of geospace environment and geodesy, ministry of education, wuhan 430079,{2. 3 State Observatory for Atmospheric Remote Sensing, wuhan 430079,{2. 1. School of Electronic Information Wuhan University Wuhan 430079 China2. Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan 430079 China3. State Observatory for Atmospheric Remote Sensing Wuhan 430079 China

The characteristics of high-latitude planetary waves (PWs) in the troposphere and lower stratosphere (TLS) are studied by using the data from radiosonde observations during 1998 to 2.06 at three Alaskan stations in USA (Nome, 64.5.°N, 165.43°W; McGrath, 62.97°N, 15..62.W; Fairbanks, 64.82.N, 147.87°W). It is found that strong PWs exist in two regions. One is around tropopause, and the other is in the polar night jet (PNJ) in winter. The PW activities are rather intermittent, and their lifetimes are no longer than two months. Among three perturbation components in zonal and meridional winds and temperature, the temperature disturbance amplitude is the smallest, and the amplitude for the meridional wind component the largest. Around the tropopause, quasi 5., 10-, and 16-day PW activities can be observed simultaneously. Among these PW components, the quasi 5.day and 10-day PW are the weakest and strongest, respectively. Moreover, PWs around the tropopause are complex and no obvious season variability can be observed. However, in the PNJ, the higher region, only obvious quasi 10-day and 16-day PWs remain, with smaller amplitudes than those around the tropopause. And significant PWs in the PNJ occur only in winter. By calculating the refractive index for PWs, it is found that there is a persistent reflection layer around 11 km, which is thick in summer and becomes thin or even disappears in winter, revealing that PWs in the stratosphere can only occur in winter. PWs in the 2.03/2.04 winter at the three stations are analyzed in detail. It is found that for the focused observation duration, the quasi 10-day and quasi 16-day waves exist mainly in the troposphere and stratosphere, respectively. The quasi 10-day wave is a standing wave in the vertical direction, with vertical wavelength about 12.km in the temperature component and larger than 2. km in the meridional component. Moreover, the tropospheric quasi 10-day wave propagates westward with the zonal numbers between 2.an

关键词： planetary waves troposphere and lower stratosphere radiosonde

Propagation of gravity wave packet near critical level

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Science china Technological Sciences 2005年第5期 60-77页

作者： YUE Xianchang & YI Fan Electronic Information School of wuhan University, Key Laboratory of geospace {2. and geodesy, ministry of education,{5., china

A couple of two-dimensional linear and fully nonlinear numerical models for compressible atmosphere are used to numerically study the propagation of the gravity wave packet into a mean wind shear. For a linear propagation wave packet, the critical level interactions are in good agreement with the linear critical level theory. The dynamically and convectively unstable regions are formed due to the critical level interaction of a finite-amplitude wave packet, but they would not break. The free exchange of potential energy with kinetic energy in the background atmosphere at rest ceases after entering the mean wind shear. However, it still goes on in the nonlinear propagation. It is shown that the nonlinear effects modify the mean flow markedly, reduce the momentum and energy propagation velocity and drop the elevation of the critical level. The gravity wave packet becomes unstable and breaks down into smaller scales in some regions. It expends much more kinetic energy than potential energy in the early phase of the breakdown. This means that the wave breakdown sets up due to the action of the shear instability rather than a convective one.

关键词： gravity wave nonlinear effect critical level instability numerical simulation.

Study on Laccase-Catalyzed Oxidation of Disubstituted Ferrocene and π-arene-π- cyclopentadienyliron Derivatives

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wuhan University Journal of Natural Sciences 2000年第3期5卷 351-356页

作者： Ji Li-cai1, Hu Pei-zhi2. Jin Chang-hua3 , Ding Zi-rong2.1. College of Adult education, wuhan University, wuhan 430072. china 2. Col lege of Chemistry and environment Science, wuhan University, wuhan 430072. C hina 3,Yiping Plant of Chemistry and Industry at Zhong Qing City, Zhong Qing 63132., china wuhan University College of Adult Education Wuhan China (GRID:grid.49470.3e) (ISNI:***) wuhan University College of Chemistry and Environment Science Wuhan China (GRID:grid.49470.3e) (ISNI:***) Yiping Plant of Chemistry and Industry at Zhong Qing City Zhong Qing China (GRID:grid.49470.3e)

It is studied that Rhus vernicifera laccase catalyzed oxidation of 2. disubstituted ferrocene and its metal complexes, π-arene-π-cyclopentadienyliron derivatives and metal meso-(tetra-4-sulfanatophenyl)porphyrin in the diethylene glycol monobutyl ether (DGBE)/phosphate buffer (V/V, 1/5.. It is found that 1,1′-bishydroxylmethyl ferrocene etc 16 compounds are new substrates of laccase. The relation of structure and function of substrates is discussed. The affective factors of laccase-catalyzed oxidation of 1,1′-bishydroxyl-methyl ferrocene—pH, temperature, substrate concentration, laccase quantity and surfactant were investigated further.

关键词： Key words Rhus vernicifera laccase disubstituted ferrocene catalytic oxidation π arene π cyclopentadienyliron

Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ5.Cr values ranging from-1.7‰to 7.3‰and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ5.Cr value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术