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Journal of Environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1.2,3 , Dieter Scharffe 2, Manfred Domroes 3, QI Yu chun 1. ZHANG Shen 1.(1. institute of Geographic {1. and Natural resources Research, chinese academy of {1., beijing 1.01.1. China E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2O emissions from intensively agricultural soils of the North China Plain during the periods of 1.95—1.96 and 1.97—1.98, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2O emissions by a factor of 24.1.28.1. the calculated annual chemical N fertilizer\|transformed N\-2O\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2O emissions, which combined with the use of chemical N increased about 20% in a year. It was calculated that there were about 0.1.% N of organic manure transformed as N 2O N. Annual mean N 2O emission from our study area of fertilized soils was estimated to be 57.1.μgN 2O/(m 2·h). A weak correlation was also found between N 2O emissions and soil available nitrogen content NH + 4.

关键词： N_2O emissions the North China Plain agricultural soils chemical nitrogen organic manure

The characteristics of chert from micro-disseminated gold deposits and their origin significance in southwestern Guizhou, China

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chinese Science Bulletin 1999年第S2期44卷 20-21页

作者： LIU Jiajun~1. LIU Congqiang~1. LIU Jianming~2 and GU Tuan~1.1. institute of Geochemistry, {1. academy of sciences, Guiyang 550002, China 2. The Reseatrch Center of mineral resources Exploration, {1. academy of sciences, beijing 1.01.1. China institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Research Center of mineral {1.s Exploration Chinese Academy of Sciences Beijing 100101 China

THE southwestern Guizhou Province has been acknowledged as one of the most important and potentialgold producing areas in the People’ s Republic of China and has attracted world-wide attention since thediscovery of a series of sediment-hosted micro-disseminated gold deposits in the last twenty years. Chertwidely occurs in the gold deposits. Study on geology and geochemistry of the chert may be important for abetter understanding of the forming condition and process of gold. 1.Characteristics of chert THE cherts are characterized by bedded, massived, pseudobrecciated and nodular structures, occurring insynsedimentary fault. The thickness of a chert bed generally varies from several meters to less than 20meters, with the maximum up to about 70 meters. Host elements are simple and concentrated in thecherts. The SiO2 concentration of the cherts varies from 86.4 % to 95.64 %, 91.95% on average

关键词： chert micro-disseminated gold deposits Guizhou.

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 sciences, beijing 100080, China 2Center of Mass Spectrometry, institute of Chemistry, chinese academy of sciences, beijing 100080, China 3Graduate School of the chinese academy of sciences, beijing 1.003., China institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the chinese {1. of sciencesbeijing 1.003. 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 41. 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.

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1.2 and Li Jianping2(1. College of Atmospheric sciences, Lanzhou University, Lanzhou 730000, China 2. LASG, {1. of Atmospheric Physics, chinese academy of sciences, beijing 1.0029, China) College of Atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1.48—2005. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1.76. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science China Earth sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1.2, YAO Tandong2,1. PU Jianchen1. ZHANG Yongliang1.& SUN Weizhen1.1. Key Laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering Research institute, {1. academy of sciences, Lanzhou 730000, China 2. institute of Tibetan Plateau Research, {1. academy of sciences, beijing 1.0085, China 1. Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 1.29A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 1.O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 20th-century warming was within the range of natural climate variability, and the warmest century was the 1.th century while the warmest decade was the 1.1.s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 1.th century. Comparing the variations of δ 1.O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 1.1.1.2 years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.

SHRIMP Dating and Recrystallization of Metamorphic Zircons from a Granitic Gneiss in the Sulu UHP Terrane

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Acta Geologica Sinica(English Edition) 2004年第1期78卷 146-154页

作者： LI Hongyaninstitute of {1. resources, chinese academy of geological sciences, beijing 1.003. Geosciences Rennes, Universite de Rennes 1. 35042 Rennes Cedex, France institute of {1. resources Chinese Academy of Geological Sciences Beijing 100037 Géosciences Rennes Université de Rennes 1 35042 Rennes Cedex France *Correspondence: LI Hongyan *Correspondence: E-mail: hyli@***

An unusual zircon SHRIMP dating result of a granitic gneiss from the Qinglongshan eclogite-gneiss roadcut section is presented in this paper. The very peculiar and complicated internal structures, as well as the very low Th/U ratios (0.01.0.08) of the zircons indicate that they were formed by metamorphic recrystallization. Strongly in contrast with previously published zircon U-Pb ages of the Dabie-Sulu UHP metamorphic rocks where protolith ages of 600-800 Ma are commonly recorded, only metamorphic age of 21.±5 Ma, defined by 1. analytical spots either in rim or in core of zircons, are recorded in this granitic gneiss. This age represents the time of the complete metamorphic recrystallization overprint on primary magmatic zircons. The recrystallization was derived by the UHP metamorphism, and was strengthened by the early stage of retrograde metamorphic fluid activity.

关键词： recrystallization of zkcon metamorphic fluid SHRIMP dating granitic gneiss Qinglongshan Sulu China

Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1.2 & JIANG Zonglin2 1. Key Laboratory of High Temperature Gas Dynamics, institute of Mechanics, {1. academy of Sci- ences, beijing 1.0080, China 2. Graduate University of {1. academy of sciences, beijing 1.003., China 1. Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. Graduate University of chinese {1. of sciences 100039 Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,China

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Science China Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1. LUO GuangQiang1.2 & YUAN GuoFu1.1.institute of Geographic {1. and Natural resources Research, chinese academy of {1., beijing 1.01.1. China 2 Graduate University of chinese academy of {1., beijing 1.0049, China 1. institute of Geographic {1. and Natural resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, China. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51.(aboveground plants were excluded), and 2.00 mg m?2 d?1.(all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

Origin, Evolution and Mechanism of the Jehol Fauna

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 203-215页

作者： Wang Si’en institute of Geology,{1., beijing Liu Linqun institute of Geology Chinese Academy of Geological Sciences Beijing

This paper deals with the geographic distribution and geological setting of the Jehol (northeastHebei-southwest Liaoning-southeast Inner Mongolia) fauna, and discusses the origination and the evolution ofits major biological groups. It is demonstrated that the Yan-Liao (northern Hebei-western Liaoning) area is theprovenance for the fauna. Why the fauna originated and developed in the area was intimately related to suchfactors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnet-ic polarity at that time, in addition to the internal factors of the organisms themselves.

关键词： Origin Evolution and Mechanism of the Jehol Fauna

An Experimental Study on Three Quaternary Phases in the Fe-Sn-Sb-S System: Pb-Free Franckeite, Pb-Free Cylindrite and (Fe, Sb)-Ottemannite s.s.

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 393-405页

作者： Li Jiuling Huang Jiashan Zhou Kezi Zhang Guilan institute of {1. Deposits, chinese academy of geological sciences, beijing institute of {1. Deposits Chinese Academy of Geological Sciences Beijing

Experimental studies on the two solid solutions franckeite s.s. and cylindrite s.s. yielded among others thePb-free endmembers of franckeite and cylindrite respectively. In these endmembers the lead content of the twomineral phases are completely substituted by bivalent tin. A third phase, ottemannite s.s. with （Fe. Sb）-bearingcompositions, was further identified in the Pb-free 4-component system Fe-Sn-Sb-S. Pb-free franckeite andcylindrite could only be synthesized as homogeneous phases at high temperatures. The ottemannite s.s. was ob-tained at 600℃ but an extensive existing range was also confirmed at temperatures below 500℃. The phase relations were discussed in the pseudoternary subsystem SnS-SnS2-FeSb2S4. The following se-quence of Pb-free phases and phase assemblages were observed under increasing Sn4+content at 600℃:herzenhergite （SnS）+franckeite, franckeite, franckeite+cylindrite, cylindrite, cylindrite+（Fe, Sb）-ottemannite.（Fe, Sb）-ottemannite. （Fe. Sb）-ottemannite+berndtite （SnS2）. The assemblage cylindrite+berndtite was identi-fied in synthetic systems involving Pb. The phase Fe. Sb-ottemannite s.s. appears to be stable only under Pb-de-ficient and high sulfur fugacity conditions.

关键词： Pb-Free Franckeite An Experimental Study on Three Quaternary Phases in the Fe-Sn-Sb-S System Ottemannite s.s Fe Sb Sn