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chinese Science Bulletin 1999年第13期44卷 1224-1228页

作者： XU Jiongxininstitute of Geography, chinese {2. of Sciences , beijing 100101, china institute of Geography Chinese Academy of Sciences Beijing China

Based on data from more than 100 alluvial rivers, a systematic comparison of flow shear stress and energy expenditure has been made between sand- and gravel-bed rivers, by plotting the relationships between channel shape (i.e. channel width-depth ratio) and hydraulic indices in a two-dimensional plane. These relationships show clearly that the four channel patterns, i.e. sand-bed meandering, sand-bed braided, gravel-bed meandering and gravel-bed braided, are located in 4 different areas that can be divided by 2.straight lines.

关键词： sand-bed river gravel-bed river channel pattern channel pattern discrimination.

Mid-Holocene climate change in North china, and the effect on cultural development

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chinese Science Bulletin 2002年第5期47卷 408-413页

作者： JIN Guiyun & LIU Dongsheng (LIU Tungsheng)institute of Cultural Relics and Archaeology of Shandong Province, Jinan 2.0012. china {2., chinese academy of Sciences, beijing 10002., china institute of Cultural Relics and Archaeology of Shandong Province Jinan China institute of geology and geophysics Chinese Academy of Sciences Beijing China

In this study, to reconstruct the paleoclimatic history, pollen and oxygen isotope were analyzed on the 160 samples of a 2.7 m peat core from Taishizhuang, Huailai County, Hebei Province. Combining our data with other information of climate history and archaeology from this area, we found that there is a close linkage between cultural development and the mid-Holocene (6000-3000 cal. aBP) environment changes. The main results and conclusions are presented as the following: The climate during 5678-5400 cal. aBP was unstable and in general colder and drier than today. From 5400 to 4800 cal. aBP the climate was much warmer and wetter than before. The climate during 4800-4300 cal. aBP was persistently cold, with an exceptional cold event occurring at 4600-4300 cal. aBP. This cold event was recorded at several other localities in Northern china even the Northern Hemisphere and played an important role in the cultural development. After the cold event, there was a return to warmer conditions between 42.0 and

关键词： North china peat mid-Holocene cold event cultural development.

Some Recognitions on the Sedimentary-Tectonic Development of the Meso-Cenozoic Basins in Eastern china

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 365-379页

作者： Liu Xun institute of geology, {2. academy of Geological Sciences, beijing chinese ACAD GEOL SCI INST GEOLBEIJINGPEOPLES R CHINA

Since Jurassic. intense and repeated tectonic movements have taken place in eastern china, of which theYanshanian movement is the most important. Thereby the development of the basins between the Jurassic andEogene in the studied areas may by divided into two different stages, i.e. the Yanshanian subcycle （J-K;） andthe North china subcycle （K;-E）. The basement and tectonic stress field of the basins played an obvious role in controlling thesedimentary-tectonic development of the basins. and down-faulted basins might form under different stressstates. Besides. the shearing stress also played an important part while the basins were forming in the notedareas.

关键词： Some Recognitions on the Sedimentary-Tectonic Development of the Meso-Cenozoic Basins in Eastern china

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china Agricultural University, beijing 100083, china 2. institute of Physics, chinese academy of Sciences, beijing 100080, china 1. College of Science China Agricultural University Beijing 100083 China 2. institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2.1. institute of Geographical Sciences and Natural Resources Research, chinese {2. of Sciences, beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 1. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952.2.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952.1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.3t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

Bio-regeneration of p-complexation desulfurization adsorbents

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Science china Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2. XING Jianmin1, XIONG Xiaochao1,2. SHAN Guobin1,2.& LIU Huizhou1 1. Laboratory of Separation Science and Engineering, institute of Process Engineering, chinese {2. of Sciences, beijing 100080, china 2. Graduate School of the chinese {2. of Sciences,beijing 100039, china 1. Laboratory of Separation Science and Engineering Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese academy of Sciences 100039 Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2. and then by auto-reduction in helium at 450℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2.HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2.HBP within 6 h and almost 100% within 2. h, when the volume ratio of oil-to-water was 1/5 mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2.HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 2. h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.

Genesis of ^(2.0)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science china Earth Sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1,2.& ZENG ZhiGang1 1 Key Laboratory of Marine geology and Environment,institute of Oceanology,{2. academy of Sciences,Qingdao 2.6071,china 2.Graduate University of {2. academy of Sciences,beijing 100049,china 1. Key Laboratory of Marine geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on 2.0Th-2.8U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 2.0Th excess.(2.0Th/2.8U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2. contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 2.0Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(2.0Th/2.8U) in OIBs actually corresponds to a lower melting *** suggests that the 2.0Th excess in MORBs is controlled by mantle melting conditions,while the 2.0Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 2.0Th are between 1.0 and 2.5 GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2.3.5 GPa(around the spinel-garnet transition zone),with their low excess 2.6Ra compared to MORBs also suggesting a deeper mantle ***,excess 2.0Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2./TiO2.with(2.0Th/2.8U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 2.0Th does not tap the spinel-garnet transition *** and MORBs in both(2.0Th/2.8U) vs.K2./TiO2.and(2.0Th/2.8U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 2.0Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 2.0Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural Sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2.1. institute of Mountain Hazards and Environment, chinese {2. of Sciences, Chengdu 610041, Sichuan, china 2. Graduated School of the chinese {2. of Sciences, beijing 100039, china chinese academy of Sciences Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) Graduated School of the chinese academy of Sciences Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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Science china Earth Sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. ZHOU Jie1, SHEN Ji3, CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. State Key Lab of Loess and Quaternary geology, institute of Earth Environment, {2. academy of Sciences, Xi’an 710075, china 2. Graduate University of {2. academy of Sciences, beijing 100039, china 3. Nanjing institute of Geography and Limnology, {2. academy of Sciences, Nanjing 2.0008, china 1. State Key Lab of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate University of chinese academy of Sciences Beijing 100039 China 3. Nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

Background contents of heavy metals in sediments of the Yangtze River system and their calculation methods

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Journal of Environmental Sciences 1995年第4期7卷 422-429页

作者： Zhang Chaosheng, Zhang Shen, Zhang Licheng, Wang Lijun(institute of Geography , chinese {2. of Sciences , beijing 100101 , china) Inst of Geography Chinese Academy of Sci Beijing China China

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关键词： Yangtze River sediments heavy metalsi robust statistics data transformation.