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Science china Earth sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1,2. XIE Zhenghui1, ZHANG Shenglei1 & LIANG Miaoling1 1. LASG, Institute of Atmospheric Physics, chinese academy of {2., beijing 10002., china 2. Graduate School of the chinese academy of {2., beijing 100039, china 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate School of the chinese academy of {2. Beijing 100039 China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. Institute of Remote Sensing & GIS, Peking University, beijing 100871, china 2. Institute of Geographical {2. and Natural Resources Research, chinese academy of {2., beijing 100101, china 1. Institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

Some properties on multivariate filter banks with a matrix factorization

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Progress in Natural Science:Materials International 2005年第2期15卷 20-30页

作者： LIAN Qiaofang1, XIAO Hongying2. and CHEN Qiuhui3(1. Department of Mathematics, beijing Jiaotong University, beijing 100044,{2. 2. Institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080,{2. 3. Department of Scientific Computing and Computer Applications, Zhongshan University, Guangzhou 5102.5,{2.) Department of Mathematics Beijing Jiaotong University Beijing 100044 China. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China. Department of Scientific Computing and Computer Applications Zhongshan University Guangzhou 510275 China

A class of multivariate filter banks with a matrix factorization has been developed by Chen et al. The main purpose of this paper is to discuss some further properties of this kind of filter bank, such as the completeness, accuracy of the corresponding scaling functions and the relationships with Daubechies' wavelets and the multi-wavelets provided by Chui and Lian. Moreover, some examples are given to show that this kind of filter bank has a higher accuracy for the scaling functions.

关键词： filter banks completeness accuracy matrix factorization

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,Graduate University of chinese academy of {2.,beijing 100049,china 3 School of Chemical Engineering and Environment,beijing Institute of Technology,beijing {12.,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,13C 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

Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2.3 & LI Gaicheng1,3 1. Engineering Research Center for Information Security Technology, Institute of Software, chinese academy of {2., beijing 100080, china 2. beijing Zhongke Ansheng Corporation of Information Technology, beijing 100080, china 3. Graduate School of the chinese academy of {2., beijing 100039, china 1. Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. beijing Zhongke Ansheng Corporation of Information Technology Beijing 100080 China 3. Graduate School of the chinese academy of {2. Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3, Shaoxiang XIONG2. Xiulan CHENG1, and Shijun QIAN1* 1Institute of Microbiology, chinese academy of {2., beijing 100080, china 2.enter of Mass Spectrometry, Institute of Chemistry, chinese academy of {2., beijing 100080, china 3Graduate School of the chinese academy of {2., beijing 100039, china Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the chinese academy of {2.beijing 100039 China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

“Double dawn”eclipse and the rotational variation of the earth

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chinese Science Bulletin 2000年第11期45卷 988-991页

作者： ZHANG Peiyu & HAN Yanben1. Purple Mountain Observatory, chinese academy of {2., Nanjing 2.0008, china 2. beijing Astronomical Observatory, chinese academy of {2., beijing 100012. National Astronomical Observatory, chinese academy of {2., beijing 100012. china Purple Mountain Observatory Chinese Academy of Sciences Nanjing China beijing Astronomical Observatory Chinese Academy of Sciences Beijing National Astronomical Observatory Chinese Academy of Sciences Beijing China

A record of 'double dawn' at State Zheng in the first year of the reign of King Yi in Western Zhou Dynasty in the chronicle 'Bamboo Annals' (Zhushu Jinian) is discussed. We think that it may be a record of an annular solar eclipse happening in 899 BC. The record and the AT, which describes the secular variation of the earth’s rotation, are analyzed and discussed.

关键词： solar eclipse earth’s rotation.

Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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Science china Earth sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3,YAN JingHua1 & HU HaiBo2.1 Institute of Tropical and Marine Meteorology,chinese Meteorological administration(CMA),Guangzhou 510080,{2. 2.Institute of Urban Meteorology,CMA,beijing 100089,{2. 3 State Key Laboratory of Severe Weather,chinese academy of Meteorological sciences,beijing 100081,{2. 1. Institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. Institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from Guangzhou mesonet Automatic Weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

Characteristics of vertical ozone distribution in the lower troposphere in the Yangtze River Delta at Lin'an in the spring of 2.01

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Science china Earth sciences 2005年第9期48卷 1519-1528页

作者： ZHENG Xiangdong1, CHAN Chuenyu2. CUI Hong2. QIN Yu3, CHAN Loyan2. ZHENG Yongguang3 & LEE Yusiang2.1. chinese academy of Meteorological {2., beijing 100081, china 2. Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Hong Kong, china 3. Department of Atmospheric {2., Peking University, beijing 100871, china 1. chinese academy of Meteorological {2. 100081 Beijing China 2. Department of Civil and Structural Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China 3. Department of Atmospheric sciences Peking University 100871 Beijing China

We analyzed vertical distributions of ozone (O3) in the lower troposphere (< 5 km above ground) at Lin’an (119.75°E, 30.30°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obta... 详细信息

We analyzed vertical distributions of ozone (O3) in the lower troposphere (30.30°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obtained from February 2. to April 13, 2.01. The results showed that the vertical O3 distributions are controlled by metrological conditions and the char- acteristics of O3 profiles are related to those of wet bulb potential temperature and wind field. O3 below 2.km showed that the strongest variability and enhanced O3 mixing ratios were associated with easterly winds that blow pollutants from the upwind source region of the Yangtze River Delta (YRD) region. Vertical O3 profiles below 5 km can be grouped into 5 categories: (1) peak mixing ratio type, (2. well-mixed type, (3) layered-structure type, (4) episodic pollution type and (5) alti- tudinal increasing type. Vertical distributions of O3 affected by regional transport of polluted air masses were investigated. Transport of polluted air from high latitudes of northern china, ac- companying subsiding motion of air and stagnant atmospheric conditions are important factors that lead to high mixing ratios of O3 at Lin’an. The stagnant atmospheric conditions associated with a continental high pressure system and pollution plume transported from the YRD and cen- tral-eastern china also lead to regional accumulation of O3 and high O3 mixing ratio at Lin’an. Long-range transport of O3 and pollutants from the Pearl River Delta in South china and in-situ O3 formation also resulted in elevated O3 mixing ratios at around 1 km altitudes and layered O3 distribution in the lower troposphere.

关键词： vertical ozone distribution, lower troposphere, Yangtze River Delta, Lin'an.

Forecasting the summer rainfall in North china using the year-to-year increment approach

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Science china Earth sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2.& GAO YuZhong3 1 Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of {2., beijing 10002., china 2.Graduate University of the chinese academy of {2., beijing 100049, china 3 Heilongjiang Meteorological administration, Harbin 150030, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the chinese academy of {2. Beijing 100049 China Heilongjiang Meteorological Administ

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2.00-2.07, with an average relative root mean square error of 2.% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2.06. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill