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Suprathermal particle events observed by WIND spacecraft in interplanetary space during 1995―1999 and their classification

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Science china(Technological sciences) 2008年第9期51卷 1542-1553页

作者： SUN LingPeng1,2. WU DeJin1 & WANG DeYu1 1 Purple Mountain Observatory, Chinese academy of sciences, Nanjing 2.0008,{2. 2.{3. school of Chinese academy of sciences, Beijing 100049,{2. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China graduate school of Chinese {2. of {3. Beijing 100049 China

Fifty-five suprathermal particle events were selected from WIND observations between 1995 and 1999. Based on systematic analysis on the observational characteristics of these events a two-parameter (the rising time and the flux ratio of electrons to protons in each event) classification method was proposed to classify these events. The three clas-sified classes are (1) impulsive electron events with the flux ratio of electrons to protons being bigger than 1 and rising time being shorter than 2.0 min, (2. impulsive proton events with the flux ratio being smaller than 1 and rising time being shorter than 2.0 min, and (3. gradual proton events with the flux ratio being smaller than 1 and the rising time being longer than 2.0 min. In the past, "impulsive solar electron events" were under in-tense research. However, because the selection standards of their velocity dispersions or pitch-angle distributions were inadequate, statistical surveys of selected events were dif-ferent from each other and even some conclusions were not consistent with the theory, for example, the relation of type-III solar radio bursts to the "impulsive solar electron events". The first class of impulsive electron events are associated with type-III radio bursts and with clear velocity dispersions; therefore they ought to originate from the Sun. The second class of the events, which have short continuance time and usually are not associated with type-III radio bursts and without velocity dispersion, are still far away from inter-planetary shocks and most of them do not one-to-one correspond to corrotating interact-ing regions (CIRs); such events are possible results of local interplanetary magnetic field reconnection or electromagnetic disturbances. Finally, about 2.3.gradual proton events of the third class occur with interplanetary shocks, the delay times of which are almost equal to the rising time. Some of these events can be understood as particle accelerations by shocks.

关键词： suprathermal particles solar wind plasma solar eruptive activity interplanetary active regions

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Prediction of Debris-flow Danger Area by Combining Hydrological and Inundation Simulation Methods

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Journal of Mountain Science 2011年第1期8卷 1-9页

作者： CUI Peng Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China graduate school of Chinese {2. of {3. Beijing 100049 China

Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2.o8. Debris flow mitigation and risk assessment is a key issue for reconstruction. The existing methods of inundation simulation are based on historical disasters and have no power of prediction. The rain- flood method can not yield detailed flow hydrograph and does not meet the need of inundation simulation. In this paper, the process of water flow was studied by using the Arc-SCS model combined with hydraulic method, and then the debris flow runoff process was calculated using the empirical formula combining the result from Arc-SCS. The peak discharge and runoff duration served as input of inundation simulation. Then, the dangerous area is predicted using kinematic wave method and Manning equation. Taking the debris flow in Huashiban gully in Beichuan County, Sichuan Province, china on 2. Sep. 2.o8 as example, the peak discharge of water flow and debris flow were calculated as 3..52.m3.s-1 and 2.5.66 m3.s-, with error of 4.15% compared to the measured values. The simulated area of debris-flow deposition was 161,500 m2. vs. the measured area of 144,097 m2. in error of 81.75%. The simulated maximum depth was 12.3.m, consistent with the real maximum depth between lO and 15 m according to the field survey. The minor error is mainly due to the flow impact on buildings and variations in cross-section configuration. The present methodology can be applied to predict debrisflow magnitude and evaluate its risk in other watersheds inthe earthquake area.

关键词： Debris flow Arc-SCS model Inundation simulation Risk analysis Wenchuan earthquake

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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3.,HUANG Zhiqin 2. 3. 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan,{2. 2. Institute of Mountain Hazards and Environment, Chinese academy of sciences, Chengdu 610041, Sichuan,{2. 3. graduate University of the Chinese academy of sciences, Beijing 100049,{2. 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan,{2. The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate University of the Chinese academy of {2. 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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Discovery of submicron diamonds within kimberlite in Liaoning Province, china and its significance

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Chinese Science Bulletin 1997年第11期42卷 939-941页

作者： BAO Yanan, T. V. Dubuchick and T. D. Liabchekov1. graduate school in Beijing, Chinese Mining University, Beijing 10008{2. china 2. Moscow Resources Institute of Mineral Materials, Russia {2. Resources Institute of Deposit Geology, Russian {{2. of sciences, Russia graduate school in Beijing Chinese Mining University Beijing China Moscow Resources Institute of Mineral Materials Russia Resources Institute of Deposit Geology Russian Academy of Sciences Russia

ALTHOUGH a lot of research work on diamond mineralogy has already been done,the formationand development of diamond leave much to be *** have done some researches onthe diamond samples with obvious crystal-growing cha... 详细信息

关键词： submicron diamond lath-shape aggregative parent material.

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Characteristics of chlorine isotope distribution and analysis on sylvinite deposit formation based on ancient salt rock in the western Tarim Basin

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Science china Earth sciences 2005年第11期48卷 1913-1920页

作者： TAN Hongbing1,2. MA Haizhou1, XIAO Yingkai1, WEI Haizhen1,2. ZHANG Xiying1 & MA Wandong1 1. Institute of Salt Lakes, Chinese academy of sciences, Xining 810008,{2. 2. {3. school of the Chinese academy of sciences, Beijing 10003.,{2. 1. Institute of Salt Lakes Chinese Academy of Sciences 810008 Xining China 2. graduate school of the Chinese {2. of {3. 100039 Beijing China

During formation of the Tarim Basin, there repetitively happened seawater invasion for it was ever connected with wide Paleo-mediterranean Sea. At the same time, for the applica-tion of tectonic and paleoenvironmental condition, the basin deposits many sequences of thick strata of evaporites, especially in its two largest subbasins of Kuqa in the north and Shaqa in the southwest. Therefore, the western Tarim Basin has been considered to be a favorable location to prospect ancient sylvinite deposit. But it is unfortunate that the Br×103.Cl ratio, as a common geochemical index to uncover clues of sylvinite deposit, is almost invalid to indicate the stage of ancient brine condensation for very low content of bromine in salt rock samples (less than 10?6 commonly) in the western Tarim Basin evaporites. Fortunately, we noticed recently that the val-ues of chlorine isotope (δ 3.Cl value) for salt rock samples follow some clear laws from place to place, which in the Shaqa subbasin, all δ 3.Cl values of salt rock samples behaved negatively and on the contrary, they all surprisingly showed positive values in the Kuqa subbasin. Based on conclusions of previous research and referring to the ratios of Br×103.Cl for salt rock or brine samples, we proved that the chlorine isotope (δ 3.Cl) could be used as an effective index to find ancient sylvinite deposit in those evaporites rock basin with low content of Br element back-ground, such as the Tarim Basin. Thus according to the new index of chlorine isotope, we con-clude that the concentration of ancient brines formed ancient salt rocks is much more concen-trated in the Shaqa subbasin than that in the Kuqa subbasin. Particularly, the δ 3.Cl value of salt rock in Kashi depression of the western Shaqa subbasin is greatly negative (

关键词： the Tarim Basin, chlorine isotope, ancient salt rock, ancient sylvinite deposit, deposit stage

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Synthetic aperture radar tomography sampling criteria and three-dimensional range migration algorithm with elevation digital spotlighting

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Science in china(Series F) 2009年第1期52卷 100-114页

作者： TAN WeiXian1,2.3., HONG Wen1,2. WANG YanPing1,2. LIN Yun1,2.3.& WU YiRong1,2.1 State Key Laboratory of Microwave Imaging Technology, Beijing 100190,{2. 2.Institute of Electronics, Chinese academy of sciences, Beijing 100190,{2. 3.graduate school, Chinese academy of sciences, Beijing 100190,{2. State Key Laboratory of Microwave Imaging Technology Beijing 100190 China Institute of Electronics Chinese Academy of Sciences Beijing 100190 China graduate school Chinese Academy of Sciences Beijing 100190 China

Based on the general geometric model of multi-baseline Synthetic Aperture Radar Tomography （TomoSAR）, the three-dimensional （3.D） sampling criteria, the analytic expression of the 3.D Point Spread Function （PSF） and the 3.D resolution are derived in the 3.D wavenumber domain in this paper. Considering the relationship between the observation geometry and the size of illuminated scenario, a 3.D Range Migration Algorithm with Elevation Digital Spotlighting （RMA-EDS） is proposed. With this algorithm 3.D images of the area of interest can be directly and accurately reconstructed in the 3.D space avoiding the complex operations of 3.D geometric correction. Finally, theoretical analyses and simulation results are presented to demonstrate the shift-varying property of the 3.D PSF and the spatialvarying property of the 3.D resolution and to demonstrate the validity of the 3.D RMA-EDS.

关键词： synthetic aperture radar tomography (TomoSAR) three-dimensional (3.D) SAR imaging 3.D sampling criteria 3.D resolution,3.D range migration algorithm with elevation digital spotlighting (RMA-EDS)

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Birthrates and delay times of Type Ia supernovae

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 586-590页

作者： WANG Bo1,2.3. LIU ZhengWei1,2.3. HAN YunKun1,2.3. LEI ZhenXin1,2.3. LUO YangPing1,2.3.& HAN ZhanWen1,2.1National Astronomical Observatories/Yunnan Observatory, Chinese academy of sciences, Kunming 650011, china 2.ey Laboratory for the Structure and Evolution of Celestial Objects, Chinese academy of sciences, Kunming 650011, china 3.6} University of Chinese academy of sciences, Beijing 100049, china 1. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China2. Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Type Ia supernovae (SNe Ia) play an important role in diverse areas of astrophysics, from the chemical evolution of galaxies to observational cosmology. However, the nature of the progenitors of SNe Ia is still unclear. In this paper, according to a detailed binary population synthesis study, we obtained SN Ia birthrates and delay times from different progenitor models, and compared them with observations. We find that the Galactic SN Ia birthrate from the double-degenerate (DD) model is close to those inferred from observations, while the birthrate from the single-degenerate (SD) model accounts for only about 1/2.2.3.of the observations. If a single starburst is assumed, the distribution of the delay times of SNe Ia from the SD model is a weak bimodality, where the WD + He channel contributes to the SNe Ia with delay times shorter than 100 Myr, and the WD + MS and WD + RG channels to those with age longer than 1 Gyr.

关键词： binaries: close stars: evolution supernovae: general white dwarfs

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Progress in the detection of human genome structural variations

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Science china(Life sciences) 2009年第6期52卷 560-567页

作者： WU XueMei1,3.& XIAO HuaSheng1,2.1 Center of Functional Genomics,Key Laboratory of System Biology,Shanghai Institutes for Biological sciences,Chinese {2. of sciences,Shanghai 2.003.,{3. 2.National Engineering Center for Biochip at Shanghai,Shanghai 2.12.3.{3. 3.graduate school of the Chinese {2. of sciences,Shanghai 2.003.,{3. 1. Center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China 3. graduate {2. of the Chinese academy of {3. Shanghai 200031 China 2. National Engineering Center for Biochip at Shanghai Shanghai 201203 China

The emerging of high-throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3.Mb in the human *** variants include copy number variations(CNVs),inversions,insertions,deletions and other complex rearrangements of DNA *** paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential ***,we highlight the array-based,PCR-based and sequencing-based assays,including array-based comparative genomic hybridization(aCGH),representational oligonucleotide microarray analysis(ROMA),multiplex amplifiable probe hybridization(MAPH),multiplex ligation-dependent probe amplification(MLPA),paired-end mapping(PEM),and next-generation DNA sequencing ***,we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable.

关键词： structural variation cytogenetic microarray PCR paired end mapping(PEM) next-generation sequencing

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Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan University Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3.1. Institute of Geographic sciences and Natural Resources Research, Chinese {2. of sciences, Beijing 100101,{3. 2. graduate University of Chinese {2. of sciences, Beijing 100049,{3. 3. College of Resources Science and Technology, Beijing Normal University, Beijing 100875,{3. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate University of Chinese academy of {2. Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2.08. There were 12.63..54 hm2.cropland de-creased between 1993.and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

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An efficient chiral synthesis of (R)-N-[3.acetyl-4-(2.hydroxy-3.isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3.1 Technical Institute of Physics and Chemistry,Chinese academy of {2.,Beijing 100080,china 2.College of Chemistry and Chemical Engineering,{3. University of Chinese academy of {2.,Beijing 100049,china 3.school of Chemical Engineering and Environment,Beijing Institute of Technology,Beijing 100081,china 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. school of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3.acetyl-4-(2.hydroxy-3.isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13. NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

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