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Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1 CCD data in Mu Us Sandland

Science china Earth sciences 2010年第S1期53卷 26-33页

作者： CHEN Wei1,2.CAO ChunXiang1,HE QiSheng1,2.GUO HuaDong3,ZHANG Hao1,2.LI RenQiang4,ZHENG Sheng1,2.XU Min1,2.GAO MengXu1,2.ZHAO Jian1,2.LI Sha1,NI XiLiang1,2.JIA HuiCong1,JI Wei1,TIAN Rong1,2.LIU Cheng1,2.ZHAO YuXing5 & LI JingLu6 1 State key laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of {2. and beijing Normal University,beijing 100101,china 2.Graduate University of {2.,beijing 100049,china 3 Center for Earth Observation and Digital Earth,{2.,beijing 100190,china 4 china key laboratory of Ecological Network Observation and Modeling,Institute of Geographical sciences and Natural Resources Research,{2.,beijing 100101,china 5 Ordos Forestry Sand Control Science Institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 017300,china 1. 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 100101 China 2. Graduate University of chinese academy of sciences Beijing 100049 China 3. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China 4. china key {2. of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 5. Ordos Forestry Sand Control Science Institute Dongsheng 017000 China 6. Inner Mongolia Biomass Thermoelectricity Limited Company Wushen 017300 China

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1 CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of china(1:1000000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1 CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,18 sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R2.of 0.817 and a root-mean-squared error of 0.173.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

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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 sciences,Peking University,beijing 100871,{2. 2.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 100101,{2. 1. School of Earth and Space sciences Peking University Beijing 100871 China2. 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 100101 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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Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern china in warm seasons

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Science china Earth sciences 2008年第5期51卷 730-739页

作者： SHI XiaoHui1, XU XiangDe1, XIE LiAn2.1 State key laboratory of Severe {2., chinese academy of Meteorological sciences, beijing 100081, china 2.Department of Marine, Earth and Atmospheric sciences, North Carolina State University, Raleigh NC2.695-82.8, USA State key laboratory of Severe {2. Chinese Academy of Meteorological Sciences Beijing 100081 China Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC 27695-8208 USA

Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 2. a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South china region during warm periods. Based on this finding, the region is referred to as a "significant impact zone" (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the "SI zone" over eastern china during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 2. a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the "SI zone". Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern china during a warm season.

关键词： warm season significant impact zone of aerosols climate change

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Next-generation sequencing technology:A technology review and future perspective

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Science china(Life sciences) 2010年第1期53卷 44-57页

作者： ZHOU XiaoGuang1,REN LuFeng1,LI YunTao2.ZHANG Meng1,YU YuDe2.& YU Jun1 1 key laboratory of Genome {2. and Information,beijing Institute of Genomics,chinese academy of sciences,beijing 10002.,china 2.Institute of Semiconductors,chinese academy of sciences,beijing 100083,china key laboratory of Genome {2. and Information Beijing Institute of Genomics Chinese Academy of Sciences Beijing China Institute of Semiconductor Chinese Academy of Sciences Beijing China

As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three *** this technical review,we look into technical characteristics of the next-generation sequencers and provide insights into their future development and *** envisage that some of the emerging platforms are capable of supporting the USD1000 genome and USD100 genome goals if given a few years for technical *** also suggest that scientists from china should play an active role in this campaign that will have a profound impact on both scientific research and societal healthcare systems.

关键词： genomics DNA sequencing next generation sequencing technologies sequencer

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Characterization of a sodium-regulated glutaminase from cyanobacterium Synechocystis sp. PCC 6803

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Science china(Life sciences) 2008年第12期51卷 1066-1075页

作者： ZHOU Jie1, ZHOU JunXia1,2. YANG HaoMeng1, YAN ChengShi1 & HUANG Fang1 1 key laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, {2., beijing 100093, china 2.Graduate School of {2., beijing 100039, china 1. key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. Graduate School of chinese academy of sciences Beijing 100039 China

Glutaminase is widely distributed among microorganisms and mammals with important functions. Lit-tle is known regarding the biochemical properties and functions of the deamidating enzyme glutami-nase in cyanobacteria. In this study a putative glutaminase encoded by gene slr2.79 in Synechocystis sp. PCC 6803 was investigated. The slr2.79 was expressed as histidine-tagged fusion protein in Es-cherichia coli. The purified protein possessed glutaminase activity, validating the functional assign-ment of the genomic annotation. The apparent Km value of the recombinant protein for glutamine was 2..6 ± 0.9 mmol/L, which was comparable to that for some of other microbial glutaminases. Analysis of the purified protein revealed a two-fold increase in catalytic activity in the presence of 1 mol/L Na+. Moreover, the Km value was decreased to 12.2.± 1.9 mmol/L in the presence of Na+. These data demon-strate that the recombinant protein Slr2.79 is a glutaminase which is regulated by Na+ through in-creasing its affinity for substrate glutamine. The slr2.79 gene was successfully disrupted in Synecho-cystis by targeted mutagenesis and the △slr2.79 mutant strain was analyzed. No differences in cell growth and oxygen evolution rate were observed between △slr2.79 and the wild type under standard growth conditions, demonstrating slr2.79 is not essential in Synechocystis. Under high salt stress condition, however, △slr2.79 cells grew 1.2.-fold faster than wild-type cells. Moreover, the photosyn-thetic oxygen evolution rate of △slr2.79 cells was higher than that of the wild-type. To further charac-terize this phenotype, a number of salt stress-related genes were analyzed by semi-quantitative RT-PCR. Expression of gdhB and prc was enhanced and expression of desD and guaA was repressed in △slr2.79 compared to the wild type. In addition, expression of two key enzymes of ammonium assimi-lation in cyanobacteria, glutamine synthetase (GS) and glutamate synthase (GOGAT) was examined by semi-quant

关键词： cyanobacteria Synechocystis putative glutaminase enzyme activity mutagenesis salt tolerance

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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 {2.llites, 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 Environmental{2.llites 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

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Interface delamination of the thermal barrier coating subjected to local heating

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Science china(Technological sciences) 2010年第12期53卷 3168-3174页

作者： WU ChenWu, HUANG ChenGuang & CHEN GuangNan Institute of Mechanics, chinese academy of sciences, beijing 100190, {2. 1. Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

To investigate the possible failure modes of the thermal barrier coating (TBC) used to protect the scramjet combustion chamber, the local heating via laser beam irradiation was utilized to simulate the service condition of high thermal flux and high temperature gradient. Firstly, the experimental method and process were described and the typical fracture morphology of the TBC under test were provided. Then, the theoretical and finite element modeling were carried out to study the temperature, deformation and stresses of the specimen when the top ceramic coat was subjected to local heating, and to demonstrate the mechanism on the failure of the TBC. It is revealed that the interface delamination shall appear and ultimately lead to the failure of the TBC under such thermal loading of local quick heating. According to the outcome of this study, the driving force of the interface delamination is influenced greatly by the key structural parameters and performance matching. Moreover, by utilizing the rules of the effects of these parameters on the fracture driving force, there is some possibility for the designer to optimize the performances of the TBC.

关键词： TBC local heating interface delamination FE modeling

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Simulation study of phase retrieval for hard X-ray in-line phase contrast imaging

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 450-458页

作者： YU Bin1,2. PENG Xiang1,2. TIAN Jindong1, NIU Hanben1, DIAO Luhong3 & LI Hua3 1. key laboratory of Optoelectronic Devices and Systems of Ministry of Education, Institute of Optoelec- tronics, Shenzhen University, Shenzhen 518060, {2. 2. State key laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072.{2. 3. key laboratory of Intelligent Information Processing, Institute of Computing Technology, chinese academy of sciences, beijing 100080,{2. 1. key laboratory of Optoelectronic Devices and Systems of Ministry of Education Institute of Optoelectronics Shenzhen University 518060 Shenzhen China 2. State key laboratory of Precision Measuring Technology and Instruments Tianjin University 300072 Tianjin China 3. key laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences 100080 Beijing China

Two algorithms for the phase retrieval of hard X-ray in-line phase contrast imaging are presented. One is referred to as Iterative Angular Spectrum Algorithm (IASA) and the other is a hybrid algorithm that combines IASA with TIE (transport of intensity equation). The calculations of the algorithms are based on free space propagation of the angular spectrum. The new approaches are demonstrated with numerical simulations. Comparisons with other phase retrieval algorithms are also performed. It is shown that the phase retrieval method combining the IASA and TIE is a promising technique for the application of hard X-ray phase contrast imaging.

关键词： X-ray optics, phase contrast imaging, phase retrieval, angular spectrum, hard X-ray.

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Development of solar-blind AlGaN 12.x12. Ultraviolet Focal Plane Arrays

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Science china(Technological sciences) 2008年第6期51卷 820-826页

作者： YUAN YongGang1, ZHANG Yan1, CHU KaiHui1, LI XiangYang1, ZHAO DeGang2.& YANG Hui2.1 State key Laboratories of Transducer Technology, Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 2.0083, {2. 2.Institute of Semiconductors, chinese academy of sciences, beijing 100083, {2. State key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper reports the development of solar-blind aluminum gallium nitride (AlGaN) 12.×12. UV Focal Plane Arrays (FPAs). The back-illuminated hybrid FPA archi- tecture consists of an 12.x12. back-illuminated AlGaN PIN detector array that is bump-mounted to a matching 12.x12. silicon CMOS readout integrated circuit (ROIC) chip. The 12.×12. p-i-n photodiode arrays with cuton and cutoff wave-lengths of 2.3 and 2.8 nm, with a sharp reduction in response to UVB (2.0―32. nm) light. Several examples of solar-blind images are provided. This solar-blind band FPA has much better application prospect.

关键词： AlGaN photodiode ultraviolet FPA solar-blind

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Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming31. South china Sea Institute of Oceanology, chinese academy of sciences. Guangzhou 510301, china 2. State key laboratory of Loess and Quaternary Geology, Earth Environmental Institute, chinese academy of sciences, Xi’an 710075, china 3. Institute of Geology and Geophysics, chinese academy of sciences, beijing 10002., china South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China State key laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

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