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Population information extraction in Chaohu watershed based on RS and GIS

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chinese Science Bulletin 2003年第2期48卷 181-183页

作者： LIU Jianjun1,2 & LI Chunlai3.1. institute of Geochemistry, chinese academy of sciences, Guiyang 550002, China 2. Graduate School, chinese academy of sciences, Beijing 10003., China 3. National Astronomical Observatories, chinese academy of sciences, Beijing 100012, China Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ ***) institute of Geochemistry Chinese Academy of Sciences Guiyang China Graduate School Chinese Academy of Sciences Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价

Enzymatic cyclization of linear peptide to plant cyclopeptide heterophyllin B

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Science China Chemistry 2006年第1期49卷 63-66页

作者： JIA Aiqun1, LI Xiang2, TAN Ninghua1, LIU Xiaozhu3. SHEN Yuemao1 & ZHOU Jun1 1. State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming institute of botany, Graduate Univer-sity of chinese academy of sciences, chinese academy of sciences, Kunming 650204, China 2. chinese Peptide Co., Ltd, Hangzhou 3.0018, China 3. southwest Forestry College, Kunming 650204, China 1. State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Kunming 650204 China 2. chinese Peptide Co. Ltd Hangzhou 310018 China 3. southwest Forestry College 650204 Kunming China

The crude enzyme (PH-1) isolated from Pseudostellaria heterophylla by ourgroup has catalyzed enzymatic cyclization of linear peptideNH_2-Gly^1-Gly^2-Leu-Pro-Pro-Pro-lle-Phe-COOH (4) into cyclopeptide heterophyllin B (HB) from plantfor the first time. To ensure this reaction, some analytical methods including TLC, HPLC, MS, NMR,and ^(13.C labeling were used to prove that the reaction of substrate 4 sharing residue ofNH-Phe-Gly-CO was successful.

关键词： Pseudostellaria heterophylla, cyclopeptides, HB, enzymatic cyclization, isotope labeled.

A trust region algorithm for bilevel programing problems

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chinese Science Bulletin 1998年第10期43卷 820-824页

作者： LIU Guoshan 1, HAN Jiye 2 and WANG Shouyang 3.1. Department of Mathematics, Beijing Normal University, Beijing 100875, China 2. institute of Applied Mathematics, chinese academy of sciences, Beijing 100080, China 3. institute of Systems Science, Chi Department of Mathematics Beijing Normal University Beijing China institute of Applied Mathematics Chinese Academy of Sciences Beijing China institute of Systems Science Chinese Academy of Sciences Beijing China

A trust region algorithm is proposed for solving bilevel programming problems where the lower level programming problem is a strongly convex programming problem with linear constraints. This algorithm is based on a tr... 详细信息

关键词： bilevel programming problem trust region algorithm global convergence.

Zonal propagation of kinetic energy and convection in the south China Sea and Indian monsoon regions in boreal summer

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Science China Earth sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2 ,HE Jinhai 2 ,TAO Shiyan 3.& JIN Zuhui 3.1.chinese academy of Meteorological sciences,Beijing 100081,China 2.Nanjing {3. of Meteorology,Nanjing 210044,China 3.{3. of Atmospheric Physics,chinese academy of sciences,Beijing 100029,China 1. chinese academy of Meteorological sciences 100081 Beijing China 2. Nanjing institute of Meteorology 210044 Nanjing China 3. chinese academy of sciences Institute of Atmospheric Physics 100029 Beijing China

Zonal propagation of kinetic energy (KE) and convection in the south China Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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Science China Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3. MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075 China 2. Qinghai institute of Salt Lakes, chinese academy of sciences. Xining 810008, China 3. institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, China 4. Department of Geography, Qinghai Normal University, Xining 810008, China chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (103. samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3. T2, T1 were formed at 14, 11.3. 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3. 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 43. m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2*)Shui-Cai WANG~2 Jun-Fang HE~2 Hui CHEN~3. 1 institute of Photonics and Photo-Technology,Northwest University,Xi'an 710069,China 2 State Key Laboratory of Transient Optics and Photonics,Xi 'an institute of Optics and Precision Mechanics,chinese {3. of sciences,Xi'an 710068.China 3.Laboratoty of Photosynthesis Basic Research,institute of botany,chinese {3. of sciences,Beijing 100093.China institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb628,Chlb646,Chlb652654,657,Chla664666,Chla674677.680and Chla682683.ere discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 628 nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652654,657,Chla664666,Chla674677.680and Chla682683.ere determined to be 1.44ns,1.43.ns,63. ps and 713.ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

Modern microbialites and their environmental signifi-cance,Meiji reef atoll,Nansha (Spratly) Islands,south China Sea

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Science China Earth sciences 2008年第4期51卷 608-617页

作者： SHEN JianWei1 & WANG Yue1,2 1 Department of Marine Geology, south China Sea institute of Oceanology Key Laboratory of Marginal Sea Geology, south China Sea institute of Oceanology and guangzhou institute of Geochemistry, chinese academy of sciences, guangzhou 5103.1, China 2 Graduate University of the chinese academy of sciences, Beijing 100049, China Department of Marine Geology South China Sea Institute of Oceanology Guangzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou

Meiji (Mischief) coral atoll, in Nansha (Spratly) Islands, south China Sea, consists of an annular reef rim surrounding a central lagoon. On the atoll rim there are either protuberant 'motu' (small coral patch reefs on the rim of atoll) islets or lower sandy cays that contain modern microbialite deposits on the corals in pinnacles and surrounding bottoms of the atoll. Microbialites, including villiform, hairy, and thin spine growth forms, as well as gelatinous masses, mats and encrustation, developed on coral colonies and atoll rim sediments between 0 and 15 m deep-water settings. The microbialites were produced by natural populations of filamentous cyanobacteria and grew on (1) bulbous corals together with Acropora sp., (2) on massive colonies of Galaxea fascicularis, (3. on dead Montipora digitata, and (4) on dead Acropora teres, some hairy microbialite growing around broken coral branches. This study demonstrates that microbial carbonates are developed in coral reefs of south China Sea and indicates that microbial processes may be important in the construction of modern reef systems. The results have significance in the determination of nature and composition in microorganisms implied in the formation ancient microbialites, and permit evaluation of the importance of microbial deposits in mo-dern coral reefs and of 'microbialites' in biogeochemical cycles of modern coral reef systems. The re-sults also provide evidence of modern analogues for ancient microbialites in shallow-water settings, and combine with sedimentological studies of ancient microbialites to understand their controls.

关键词： Microbialite Meiji reef Nansha Island south China Sea

Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure

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Science China(Life sciences) 2006年第2期49卷 97-104页

作者： SHEN Sile1,3. WANG Zhenwei3. SHAN Xiaohui2, WANG Hua3. LI Ling3. LIN Xuyun2, LONG Likun2, WENG Kenan4, LIU Bao2 & ZOU Guangtian1 1. National Laboratory of Superhard Materials, Jilin University, Changchun 13.012, China 2. institute of Genetics and Cytology, Northeast Normal University, Changchun 13.024, China 3. College of Life Science, Jilin University, Changchun 13.012, China 4. guangzhou institute of Geochemistry,{3., guangzhou 510640, China 1. National Laboratory of Superhard Materials Jilin University Changchun 130012 China 3. College of Life Science Jilin University Changchun 130012 China 2. institute of Genetics and Cytology Northeast Normal University Changchun 130024 China 4. guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

By using high-pressure treatment, two mutant lines were obtained from agenetically stable japonica rice cultivar Bijing3.. Genomic DNA of the mutant lines, together withthe original line (Bijing3.), was either undigested or digested by Hpa ⅡIMspⅠ, and then subjectedto molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCRamplification profiles of both markers are apparent in the two mutant lines compared with theoriginal rice cultivar, suggesting that there had been both sequence changes and DNA methylationmodifications in the mutant lines. southern blot analysis using diverse sequences, including twocellular genes (S2 and S3., a set of retrotransposons (Osr7, Osr3., Tos19 and more), and a MITEtransposon family (mPing and Pong), confirmed the results, and indicated that changes in DNAmethylation pattern, genomic structure, and possible activation of some transposons indeed occurredin the mutant lines. Moreover, these changes are stably maintained through selfed generations and indifferent organs. Thus, our results indicate that it is possible to obtain stable mutants in riceby high pressure treatments, and the molecular basis of the mutants may include both genetic andepigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plantmutagenesis.

关键词： DNA methylation, genomic changes, high pressure, mutagenesis, rice.

Superlarge ore deposits and development of China's mineral resources

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chinese Science Bulletin 1999年第15期44卷 1436-1440页

作者： ZHAO Zhenhuaguangzhou institute of Geochemistry , chinese academy of sciences , guangzhou 510640, China Guangzhau institute of Geochemistry Chinese Academy of Sciences Guangzhou China

The ever increasing demand of mineral resources in China was assessed and it is suggested that the development of superlarge ore deposits was the best way to meet such demand. Research and exploitation of superlarge ore deposits can bring great economic and social benefits to the society. It is also the best way to a better integration of resource industry development and environmental protection and therefore provides a basis of sustainable development of China. China has made important advancements in the research of superlarge ore deposits and especially in classification, selectivity and confinement of deposit types and temporal and spatial distributions. It is suggested that the metallodynamics and the interaction between the crust and the mantle and the core should be studied. At the same time, a new concept of resources should be established in order to build a new integrated system for research, and resource development and environmental proiection.

关键词： superlarge ore deposit metallodynamics resource-environmental integration.