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Prediction method for October 2.03 solar storm

Science China(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3, WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of sciences, Beijing 100080, China 2. Graduate school, Chinese Academy of sciences, Beijing 100039, China 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, China State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate school Chinese Academy of Sciences Beijing China Institute of Meteorology PLA University of Science and Technology Nanjing China

Aiming at two intense shock events on October 2. and 2., 2.03, this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

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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, China 2.Key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, Wuhan 430079, China 3 school of {2. and Space sciences, Peking University, Beijing 100871, China school of Electronic Information Wuhan University Wuhan China Key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan China school of earth and Space {2. 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

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Response of remotely sensed Normalized Difference Water Deviation Index to the 2.06 Drought of eastern Sichuan Basin

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Science China earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2. GAO ZhiQiang3 & PENG Jian4 1 school of Water Resource and Hydropower, Sichuan University, Chengdu 610065, China 2.national Satellite Meteorological Center, China Meteorological Administration, Beijing 100081, China 3 Institute of Geographic {2. and Natural Resources Research, Chinese Academy of {2., Beijing 100101, China 4 school of environmental {2., Peking University, Beijing 100871, China school of Water Resource and Hydropower Sichuan University Chengdu China national Statellite Meteorological Center China Meteorological Administration Beijing China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China school of environmental {2. Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2.06 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2.01―2.06 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2.06 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

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Effects of MoO_3 Amounts on Sintering and Electrical Properties of Ce_(0.8)Nd_(0.2.O_(1.9)

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Chemical Research in Chinese Universities 2012年第1期28卷 9-13页

作者： ZHOU De-feng1, ZHAO Gui-chun1, YANG Mei1, XIA Yan-jie2.and MENG Jian2.1. school of Chemistry and Life Science, Changchun University of Technology, Changchun 130012. P. R. China 2. State Key Laboratory of Rare earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of {2., Changchun 13002., P. R. China school of Chemistry and Life Science Changchun University of Technology Changchun 130012 Changchun Institute of Applied Chemistry Chinese Academy of Sciences State Key Laboratory of Rare Earth Resources Utilization Changchun 130022

The high purity （Ce0.8Nd0.2.1.9）1-x（MoO3）x（x=0, 0.005, 0.010, 0.02.; Ce0.8Nd0.2.1.9=NDC） solid solutions were prepared by modified sol-gel method. The structures and electric conductivities were characterized by X-ray diffraction（XRD）, field-emission scanning electron microscopy（FESEM） and electrochemical impedance spectros copy（EIS）. The XRD results show that the materials were pure phase with a cubic fluorite structure. Compared to the undoped-NDC samples, MoO3 doped-NDC showed higher sintered density（over 96%） at reduced sintering tempera ture. The electric conductivity（σt） of （Ce0.8Nd0.2.1.9）1-x（MoO3）x at 400 °C was 9.58×10-4 S/cm when x=0.010, which was higher than that of undoped-NDC samples（σt=3.2.×10-4 S/cm）. The obtained optimal amount of the MoO3 was x=0.010 in this system.

关键词： Neodymium-doped ceria Molybdenum oxide Sol-gel method Grain boundary conductivity

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Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science China earth sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2. AN Lizhe1, 3, WU Guangjian2. XU Baiqing2. MA Xiaojun 3, LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, China 2. Institute of Tibetan Plateau Research, Chinese Academy of sciences, Beijing 100085, China 3. College of Life Science, Lanzhou University, Lanzhou 730000, China Chinese Academy of sciences Lanzhou University

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 2..4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

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Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern China

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Science China earth sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1,2. DENG Chenglong1, ZHU Rixiang1 & XIE Fei3 1. Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sci- ences, Beijing 10002., China 2. school of the earth {2. and Resources, China University of Geo{2., Beijing 100083, China 3. Hebei Province Institute of Cultural Relics, Shijiazhuang 050000, China Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China school of the earth {2. and Resources China University of Geosciences Beijing China Hebei Province Institute of Cultural Relics Shijiazhuang China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern China, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3 and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

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Statistical study on the relationship between halo CME and coronal dimming

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Science China(Technological sciences) 2010年第7期53卷 2020-2024页

作者： LIU Kai1, XIA LiDong2. CHEN Yao2.& SONG HongQiang2.1 school of earth and Space {2., University of Science and Technology of China, Hefei 2.002., China 2.Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, school of Space Science and Physics, Shandong University at Weihai, Weihai 2.42.9, China school of earth and Space {2. University of Science and Technology of China Hefei China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Shandong University at Weihai Weihai China

The data from SOHO/EIT and SOHO/LASCO observations are used to determine the relationship between coronal dimming and full halo CME (coronal mass ejection). The events of full halo CME examined in this study were observed by LASCO co-ronagraphs and taken from the CD AW CME catalog from 1996 to 2.08. Dimming events are identified by using difference images taken by EIT at the 195 A passband. We found strong relationship between full halo CMEs and the coronal dimming events, with up to 93.3% of the front-side halo CMEs associated with the EIT 195 A dimming events. Full halo CMEs that show no clear signatures of dimming usually have lower sky plane velocities (<700 km/s) compared to the mean velocity of CMEs associated with dimming.

关键词： Sun coronal mass ejection coronal dimming extreme-ultraviolet

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ECSTM study of adsorption of C_(60),C_(70),C_(86) and Y@C_(82. on Au(111)

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Science China Chemistry 2010年第8期53卷 1705-1710页

作者： SU GuiJin1,JIA ManKe1,GAN LiHua2.& SHI RuiFang1 1State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-environmental {2.,Chinese Academy of {2.,Beijing 100085,China 2.4} of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,China State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-environmental sciences Chinese Academy of Sciences Beijing China school of Chemistry and Chemical Engineering Southwest University Chongqing China

The adsorption of a variety of fullerenes (C60,C70,C86,Y@C82. on Au(111) electrode surfaces was comprehensively investigated in 0.1 M HClO4 by electrochemical scanning tunneling microscopy (ECSTM).In the ordered C60's adlayer,C60 molecules formed either (2.1/3) × 2.3～(1/3))or "in-phase" *** high resolution STM image shows that the C60 cage is not simply round but shows a bifurcated *** adsorption orientation of C60 on Au(111) is tentatively *** the ordered C70's adlayer,the perpendicular fullerene molecules are the main adsorption mode and form (2.3～(1/3) × 2.3～(1/3)) ***,for C86 and Y@C82.the ordered adlayer could not be obtained on Au(111) under the present *** differences may be due to the different molecular shapes and sizes,and the encapsulated metal atom which affects the lattice matches with the *** adsorption of fullerene molecules on Au(111) from disorder to order could be tuned simply by steering the dimensional sizes or shapes of the fullerenes used.

关键词： C60 C70 C86 Y@C82 ECSTM Au(111)

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Development of environmental monitoring satellite systems in China

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Science China earth sciences 2010年第S1期53卷 1-7页

作者： LI GuoPing1 & CAO ChunXiang2.1 school of earth and Space {2.,Peking University,Beijing 100871,China 2.State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of {2. and Beijing Normal University,Beijing 100101,China school of earth and Space {2. Peking University Beijing China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China

With the increase in global environmental problems,the necessity and urgency of remote sensing technology being applied to environmental monitoring has been widely recognized around the *** has launched the environment and disaster monitoring and forecasting small satellite constellation HJ-1A/B and the FY3 atmosphere and environmental satellite,but they still cannot fully satisfy requirements for environmental *** paper summarizes the current status of satellite environmental monitoring in China and the existing problems of inadequate load design and low data utilization efficiency,and discusses the demand for environmental monitoring *** on the development of foreign satellite systems for environmental monitoring,the future development and key tasks of the environmental monitoring satellite system in China is discussed,as are some related initiatives.

关键词： environmental satellite environmental monitoring global climate change specialty load satellite system

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A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science China earth sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3 & TIAN Fuqiang1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China 2. Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, China 3. Department of Civil Engineering, Massachusetts Institute of Technology, USA Department of Hydraulic Engineering Tsinghua University Beijing China Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Department of Civil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

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