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chinese Journal of Population,resources and Environment 2005年第2期3卷 35-41页

作者： Duan Juan 1,2. Lu Qi 1 & Wen Yuyuan 3. institute of geographic {2. and {3. resources research, chinese academy of sciences,beijing 100101, china2.Graduate School of chinese academy of sciences, beijing 10003.,{12.3.institute of Regional Economics and Urban Management {2., Renmin Univercity of china,beijing 100872. china institute of geographic {2. and {3. resources research Chinese Academy of Sciences Beijing 100101 China Graduate School of chinese academy of sciences Beijing 100039 China institute of Regional Economics and Urban Management sciences Beijing 100872 China

Urban-rural interaction and conjunctionaldevelopment is the effective way of harmonizingurban-rural relationship and promoting urban-ruraldevelopment. However, there are differences in thelevel of urban-rural interaction and conjunctionaldevelopment of china. How to measure and reflectthe difference properly is a decision-makingfoundation for optimizing urban-rural developmentof different regions. The paper employs multiplemethods to evaluate and order the urban-ruralinteraction and conjunctional development of 3.provinces (municipalities) in china. Kendall’s Wconsistency coefficient is employed to give a consistenttest for the evaluation result series, and the resultsof multiple methods are aggregated as the finalevaluation value. The results reflect the level ofregional urban-rural interaction and conjunctionaldevelopment in china.

关键词： Urban-rural interaction urban-ruralconjunctional development comprehensive evaluation consistency test.

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science china(Technological sciences) 2004年第z1期47卷 60-71页

作者： wang Zhonggen1, ZHENG Hongxing1, liu Changming1, , WU Xianfeng2.2.& ZHAO Weimin3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, {2. of {2. Science and {3. resources research, chinese academy of sciences, beijing 100101, china 2. {2. of Environmental Science, beijing Normal University, beijing 100875, china 3. Water resources Conservation Committee of Yellow River, Zhengzhou 450003. china chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Wet-chemical synthesis and characteristics of Au nanoshell

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Science china Chemistry 2005年第5期48卷 431-435页

作者： liu Zhongxin1,2. SONG Hongwei1, YU Lixin1,2. YANG Linmei1,2.& PAN Guohui1,2.1. Key Laboratory of Excited State Physics, Changchun institute of Optics, Fine Mechanics and Physics,{2., Changchun 13.03.,{2. 2. Graduate School of the{2., beijing 10003.,{2. 1. Key Laboratory of Excited State Physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 2. nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 3.℃ (5 W/cm2. irradiation area was 2.cm2.. This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.

Comparative analysis of temperature and CO2.fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, wang Tianduo, SUN Xiaomin and ZHANG Renhua ( chinese {2. of Meteorological Science, {3. 100081, china institute of geographic sciences and natural resources research, chinese academy of sciences,{12., china Mathematics Department, Ocean University of china, Qingdao 2.6071, china Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 2.003.2} china) [a]chinese academy of Meteorological Science Beijing China [b]chinese academy of {2. Institute of Geographic sciences and Natural Resources Research Beijing China [c]Mathematics Department Ocean University of China Qingdao China [d]chinese academy of {2. Shanghai Institute of Plant Physiology and Ecology Shanghai China

Comparative study of spectral properties of temperature and CO2.fluxes measured by eddy covariance method at Yucheng (3.°57'N, 116°3.'E, 2. m a.s.l., in the North china Plain) and at Lhasa (2.°41'N, 91°2.'E, 3.88 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2.fluxes (F) measured at Yucheng ( T1 and F1) and Lhasa ( T2.and F2. . (2. Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3. Comparison of temperature and CO2.fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1, F1, T2.and F2.are 0.05 Hz, 0.03.Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

Growth characteristics and response to climate change of Larix Miller tree-ring in china

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Science china Earth sciences 2010年第6期53卷 871-879页

作者： SUN Yu1,4, wang LiLi1,2.3. CHEN Jin5, DUAN JianPing1,4, SHAO XueMei1,2.& CHEN KeLong6 1 {3. of {2. {3. and natural resources research, chinese academy of sciences, beijing 100101, china 2.{3. of Tibetan Plateau research, chinese academy of sciences, beijing 100085, china 3.{3. of Desert and Meteorology, china Meteorological Administration, Urumqi 83.002. china 4 Graduate University of chinese academy of sciences, beijing 100049, china 5 {3. of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044, china 6 School of Life and Geography {3., Qinghai Normal University, Xining 810008, china 1. institute of geographic {2. and {3. resources research Chinese Academy of Sciences Beijing 100101 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Desert and Meteorology China Meteorological Administration Urumqi 830002 China5. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China6. School of Life and Geography Sciences Qinghai Normal University Xining 810008 China

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

Properties and applications of cold supersonic gas jet

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1,2.MA Xinwen1,2.liu Huiping2.LI Bin1,2.& ZHU Xiaolong1,2.1. institute of Modern Physics,{2. {2. of {3.,Lanzhou 73.000,china 2. Graduate University of chinese academy of sciences,{13. 100049,china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.

Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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Science china Earth sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1, PENG Suping1, ZHANG Zhongjie2.& liu Zhenkuan3.1. china University of Mining & Technology, {2. 100083. china 2. {3. of Geophysics, chinese academy of sciences, beijing 100101, china 3. Exploration and Development research {3. of Daqing Oilfield, Daqing 163.12. china 1. china University of Mining & Technology Beijing 100083 China 2. institute of Geophysics Chinese Academy of Sciences Beijing 100101 China 3. Exploration and Development research institute of Daqing Oilfield Daqing 163712 China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： liu Feng1,2. HU Fei2.& ZHU Jiang2.1. College of Environmental sciences, Peking University, {2. 100871,{2. 2. LAPC, {3. of Atmospheric Physics, chinese academy of sciences, {2. 10002.,{2. 1. College of Environmental sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science china Earth sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3. GUO Zhengtang2.1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & liu Tungsheng1 1. institute of Geology and Geophysics,{2., {2. 10002.,{3. 2. institute of Earth Environment,{2., Xi’an 710075,{3. 3. institute of Geomechanics, chinese {13. of Geological sciences, {2. 100081,{3. 1. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 2.3.1.m sequence varies from 6 to 13.μm and the > 63.μm fraction representsonly 5.3. in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

A study on environmental aridity over northern and southern to Qinling Mountains under climate warming

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Journal of geographical sciences 2001年第2期11卷 193-201页

作者： YAN Jun-ping~1, liu Yan-sui~2.(1. College of Tourism and Environment, Shaanxi Normal University, Xi’an 710062.{3. 2. {2. of {2. {3. and natural resources research, CAS, beijing 100101,{3.) College of Tourism and Environment Shaanxi Normal University institute of geographic {2. and {3. resources research CAS

Based on the data up to 1999 from hydroclimatological departments, this pape analyzes the climatic divide implications of the Qinling Mountains in regional response to the process of climate warming, due to which the grades of dryness/wetness (GDW) in 100 years show that the northern region has entered a drought period, while the southern is a humid period. In a course of ten years, the D-value of annual average air temperature over southern Shaanxi (the Hanjiang Valley) and the Central Shaanxi Plain (the Guanzhong Plain) has narrowed, i.e., the former with a slight change and the latter with rapid increase in temperature. Both regions were arid with the decrease in precipition D-value, namely the plain became warmer while the south was drier. The Qinling Mountains play a pronounced role in the climatic divide. The runoff coefficient (RC) of the Weihe River decreases synchronously with that of the Hanjiang due to climate warming. The RC of Weihe dropped from 0.2.in the 1950s to less than 0.1 in the 1990s. The Weihe Valley (the Guanzhong Plain) is practically an arid area due to shortage of water. The successive 0.5, 1.0°C temperature anomaly over china marks, perhaps, the improtant transition period in which the environment becomes more vulnerable than before. The study shows the obvious trend of environmental aridity, which is of help to the understanding of regional response to global climate change.

关键词： climate change aridity Qinling Mountains