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A comparative analysis on two solar proton events

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chinese Science Bulletin 2007年第1期52卷 47-51页

作者： LE GuiMing1,2.3,4, HAN YanBen2.& ZHANG YiJun3 1 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, china Meteorological Administration, beijing 100081, china 2.national Astronomical Observatories, chinese academy of Sciences, beijing 100012. china 3 chinese academy of Meteorological Sciences, china Meteorological Administration, beijing 100081, china 4 national center for Space Weather, china Meteorological Administration, beijing 100081, china Key Laboratory of Radiometric Calibration and Validation for EnvironmentalSatellites China Meteorological Administration Beijing 100081 China

This paper presents a comparative analysis on the two Solar Proton Events (SPE), which occurred on 14 July 2.00 (Bastille Day) and 2. October 2.03 (2.OCT03) respectively. It is found that although the peak flux of the latter seemed to be greater than that of the former based on geostationary observations, the maximum intensities of the energetic protons (>10 MeV and 30 MeV) during the Bastille Day event were all higher than those of the 2.OCT03 event according to the interplanetary observations. Further analysis indicated that the quantity of the seed particles, which could be accelerated to the energies exceeding 10 and 30 MeV by the Coronal Mass Ejection (CME)-driven shock on 14 July 2.00, was far larger than that of the 2.OCT03 event. In the Bastille Day case, when the CME approached to the height around 14 R⊙, the CME-driven shock would reach its maximum capacity in accelerating the solar en- ergetic protons (>100 MeV). In contrast, on 2. October 2.03, when CME approached to the height about 58R⊙, the CME-driven shock reached its highest potential in accelerating the solar energetic protons of the same category. At this moment, the peak flux (>100 MeV) was about 155 pfu, which was much lower than 355 pfu measured on 14 July 2.00. This demonstrated that in the Bastille Day event, the quantity of the seed particles, which could be accelerated to the energy beyond 100 MeV, was significantly larger than its counterpart in the 2.OCT03 case. Therefore, the peak flux of an SPE event depends not only on the interplanetary intensity of the solar energetic particles, but also on the velocity of the associated CME-driven shock, and the quantity of the seed particles as well as on the interplanetary magnetic en- vironment. This paper also reveals that the magnetic sheath associated with ICME on 2. October 2.03 captured a large number of solar energetic protons, including those having energy greater than 100 MeV.

关键词：太阳质子 CME 太阳耀斑太阳系

Preliminary discussion of low-salinity hydrothermal fluid mineralization

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chinese Science Bulletin 1999年第S2期44卷 141-143页

作者： ZHENG Mianping R & D center of Saline Lake and Epithermal Deposits, chinese {2. of geological Sciences, beijing 100037, china R and D center of Saline Lake and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China

REVIEWING the history of the geology of mineral deposits, we may find that in the first fifty years of thetwentieth century the magmatic-hydrothermal theory of ore deposition was the most prevalent, whichgave impetus to the development of the geology of mineral deposits. In the 1960s, the drilling of theSalton Sea geothermal field, California, the United States, and discovery and study of the Red Sea seafloor hot brines and large amounts of metal sulfides removed therefrom led to the rise of the brine theory ofmineral deposition, thus elucidating the origin of massive metal sulfides and promoted the discoveryand exploration of metal deposits. After the 1970s and the 1980s, through a study of the hydrothermal ore fluids of modern hotsprings. geologists came to realize that there exist low-salinity hydrothermal ore fluids other than

关键词： low-salinity hydrothermal fluid mineralization.

A preliminary study on vegetation-erosion dynamics and its applications

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Science china Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2., WANG Guangqian 1 , LI Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic Engineering, Tsinghua University, beijing 100084, china 2. Inter{2. Research and Training center on Erosion and Sedimentation, beijing 100084, china 1. Department of Hydraulic Engineering Tsinghua University 100084 Beijing China 2. International Research and Training center on Erosion and Sedimentation 100084 Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

A preliminary study on seismic design criteria of offshore platforms in Bohai Sea of china

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 223-231页

作者： Peng Yanju1,Lu Yuejun1,Yan Jiaquan2.Tang Rongyu1,Wang Junqin3 and Li Jiagang3 1. Institute of Crustal Dynamics,china Earthquake Administration,beijing 100085,china 2. Institute of Geophysics,china Earthquake Administration,beijing 100081,china 3. beijing Research center of china national Offshore Oil Corp.,beijing 10002.,china Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

This paper analyzes the seismicity in Bohai Sea,introducing a shape factor K to characterize the seismic risk distribution in sub-regions of the sea. Based on the seismic design ground motions for 46 platforms located in the Bohai Sea,a statistical analysis was performed for different peak ground acceleration (PGA) ratios at two different probability levels. In accordance with the two-stage design method,a scheme of two seismic design levels is proposed,and two seismic design objectives are established respectively for the strength level earthquake and the ductility level earthquake. By analogy with and comparison to the chinese seismic design code for buildings,it is proposed that the probability level for the strength level earthquake and ductility level earthquake have a return period of 2.0 and 1000 - 2.00 years,respectively. The validity of these proposed values is discussed. Finally,the PGAs corresponding to these two probability levels are calculated for different sub-regions of the Bohai Sea.

关键词： fixed offshore platform seismic design level seismic design objective return period Bohai Sea

Factors governing formation of todorokite at atmospheric pressure

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Science china Earth Sciences 2005年第10期48卷 1678-1689页

作者： CUI Haojie1, FENG Xionghan1, LIU Fan1, TAN Wenfeng1 & HE Jizheng2.1. College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, china 2. Research center for Eco-environmental Sciences, {2. academy of Sciences, beijing 100085, china College of Resources and Environment Huazhong Agricultural University Wuhan china Research center for Eco-environmental Sciences chinese {2. of Sciences beijing china

Todorokite commonly occurs in Earth surface environments. The factors governing formation of todorokite, such as reaction temperature, metal ions, dissolved O2.and pH, were investigated in this paper. Results showed that the forming rate of todorokite and its crystallinity decreased with falling reaction temperature, and the effect of temperature was more significant than that of other parameters. Nature of metal ions in the interlayer of buserite precursor and the structure of the buserite precursor obviously affected buserite transformation into todorokite. Weak bonding between the metal ions and MnO6 layer of buserite was favorable to todorokite formation. The rate of todorokite formation was promoted at a lower temperature with appropriate bubbling of O2. The pH in the system slightly influenced the todorokite formation, and todorokite could also be formed in a weak alkali medium or in a slightly acidic medium. Aged buserite pre-cursor more easily form todorokite than the unaged one.

关键词： todorokite, buserite, manganese oxide mineral, atmospheric pressure, transformation.

New Institutional Mechanism in china Facilitating the Global Sustainability——Environment to Be Counted in Officials' Performance Rating

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chinese Journal of Population,Resources and Environment 2004年第4期2卷 49-52页

作者： Ren Jingming Wang Rusong Research center for Eco-Environmental Science, chinese {2. of Science, beijing 100085, china Development Research center of chinese geological Survey, beijing 100037, china Research center for Eco-Environmental Science Chinese Academy of Science Beijing 100085 China Development Research center of chinese {2. Survey Beijing 100037 China

Having argued the importance of china's sustainable development in global sustainability, the authors review the achievements of china in sustainable development, especially its institutional construction. Environment to be counted in official's political performance rating system is thought of as a new institutional mechanism in china facilitating its sustainable development and then global sustainability. Then its significance is narrated and visions in future are envisioned. In the end, certain concrete suggestions for the rating system are given in a practical way.

关键词： official’s performance rating System institutional mechanism china’s sustainable development global sustainability

Characterization of GLUT4-containing vesicles in 3T3-L1 adipocytes by total internal reflection fluorescence microscopy

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Science china(Life Sciences) 2009年第7期52卷 665-671页

作者： WANG Yan1,2.ZHANG JinZhong1,2.CHEN Yu1,2.JIANG Li1,2.JI Wei1,2.& XU Tao1 1 national Laboratory of Biomacromolecules,Institute of Biophysics,chinese {2. of Sciences,beijing 100101,china 2.Graduate University of chinese {2. of Sciences,beijing 100049,china 1. national Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of chinese academy of Sciences Beijing 100049 China

Insulin-responsive GLUT4(glucose transporter 4) translocation plays a major role in regulating glucose uptake in adipose tissue and *** or not there is a specialized secretory GSV(GLUT4 storage vesicle) pool,and more importantly how GSVs are translocated to the PM(plasma membrane) under insulin stimulation is still under *** the present study,we systematically analyzed the dynamics of a large number of single GLUT4-containing vesicles in 3T3-L1 adipocytes by TIRFM(total internal reflection fluorescence microscopy).We found that GLUT4-containing vesicles can be classified into three groups according to their mobility,namely vertical,stable,and lateral GLUT4-containing *** these groups,vertical GLUT4-containing vesicles exclude transferrin receptors and move towards the PM specifically in response to insulin stimulation,while stable and lateral GLUT4-containing vesicles contain transferrin receptors and show no insulin *** data demonstrate that vertical GLUT4-containing vesicles correspond to specialized secretory GSVs,which approach the PM directly and bypass the constitutive recycling pathway.

关键词： GLUT4 IRAP-pHluorin GSV transferring TIRFM

An analysis of the wide area differential method of geostationary orbit satellites

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 310-314页

作者： CAI ChengLin1,2.3?, LI XiaoHui1 & WU HaiTao1 1 national Time Service center, {2. academy of Sciences, Lintong 710600, china 2.Hunan Institute of Humanities, Science and Technology, Loudi 417000, china 3 Graduate University of {2. academy of Sciences, beijing 100049, china 1. national Time Service center Chinese Academy of Sciences Lintong 710600 China 2. Hunan Institute of Humanities Science and Technology Loudi 417000 China 3. Graduate University of chinese academy of Sciences Beijing 100049 China

This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation.

关键词： geostationary orbitsatellite dilution of precision satellite ephemeris errors satellite clock errors wide area differential method

Solvation effects on brain uptakes of isomers of ^(99m)Tc brain imaging agents

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chinese Science Bulletin 2002年第21期47卷 1786-1791页

作者： JIA Hongmei, MA Xiaohui, WANG Cunxin & LIU Boli1. Department of Chemistry, beijing Normal University, beijing 100875,{2. 2. center for Biomedical Engineering, beijing Polytechnic University, beijing 10002.,{2. 1. Department of Chemistry Beijing Normal University Beijing 100875 China 2. center for Biomedical Engineering Beijing Polytechnic University Beijing 100022 China

Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists between the logarithm of the brain uptake and the electrostatic hydration free energy for the isomers of 99mTc-brain radiopharmaceu-ticals, but also a linear relationship exists between the logarithm of the ratio of the brain uptake of the syn isomer to that of the anti one and the difference between the electrostatic hydration free energy of the syn-isomer and that of the anti one. Furthermore, the investigation on the important factors influencing the brain uptakes of 99mTc-radiophar-maceuticals and the reasons of the different biodistribution of the isomers of the 99mTc-complexes is explored at the molecular level. The results may provide a reference for the rational drug design of brain imaging agents.

关键词： 99mTc-brain imaging agent isomer brain uptake electro-static hydration free energy.