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Wuhan University Journal of Natural sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2. 3., LIU Qing 1 1. Chengdu Institute of Biology, chinese academy of {2., Chengdu 61004., Sichuan,China 2. Graduate University of chinese academy of {2., beijing 10004., China 3. academy of Land Reconnaissance and Layout of Sichuan Province , Chengdu 61003., Sichuan, China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan China Graduate University of chinese academy of {2. Beijing China academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of China, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2.01. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2.01, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Modeling of elastic wave propagation on a curved free surface using an improved finite-difference algorithm

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 633-648页

作者： WANG Xiuming1,3.& ZHANG Hailan2.1. CSIRO Petroleum, ARRC, PO BOX 113., Technology Park, Bentley, WA 6102. Australia 2. Institute of Acoustics, {3. academy of {2., beijing 100080, China 3. Present address: Institute of Acoustics, {3. academy of {2., beijing 100080, China 1. CSIRO Petroleum ARRC Technology Park PO BOX 1130 6102 Bentley WA Australia 2. Institute of Acoustics Chinese Academy of Sciences 100080 Beijing China

Based on existing direct and imaging methods of a staggered finite-difference scheme, an improved algorithm for staggered finite-difference is proposed to implement rugged topographic free boundary conditions. This method assumes that the free surface can be implemented with horizontal and vertical free surface segments and their corners; the free surface passes through the grid points of shear stress components, instead of the normal stress components. Imaging is carried out for stress components in both horizontal and vertical directions, thus increasing the accuracy. To update particle- velocities, imaging and updating are first performed in the horizontal direction, and then in the vertical direction. The numerical results for elastic flat horizontal free surface with the imaging method and those for flat free surfaces of various slope angles with the proposed method are compared, and are shown to be in good agreement. The advantage of the proposed method is that only the stresses are dealt with in implementing the free surface into the staggered algorithm, which improves computation efficiency.

关键词： elastic wave simulation, curved free surface, staggered finite-difference, algorithm stability.

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, {3. {4. of {2., beijing 100080, China 2. Graduate {4. of the {3. {4. of {2.,beijing 10003., 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 {2. of {4. 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 4.0℃ 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.

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2. JIAN Zhimin3.& HE Jinhai4.1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of {2., beijing 10002., China 2. Institute of Climate and Environment, chinese academy of Meteoro- logical {2., beijing 100081, China 3. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. China 4. Department of Atmospheric {2., Nanjing Institute of Meteorol- ogy, Nanjing 2.004., China 5. Graduate school of the chinese academy of {2., beijing 10003., China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate school of the chinese {2. of {3. Beijing 100039 China Institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine Geology Tongji University Shanghai 200092 China Department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14.MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14.MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14.MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 4.°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese academy of {2.,{3. 100012.China 2.Graduate {4. of chinese academy of {2.,{3. 10004.,China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate school of chinese {2. of {3. Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 113. nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12.⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 3.%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. Institute of Engineering Thermophysics, chinese academy of {2., {4. 100080, China 2. Graduate {4., chinese academy of {2., {4. 100080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. Graduate school Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

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Science China(Technological sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2. GAO Yanhua1,3. CHENG Yu1,3. WEI Zheng1,3. XIAO Qing1,4. LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, {4. academy of {2., beijing 100101, China 2. Geography and Environment College, Jiangxi Normal University, Nanchang 3.002., China 3. Graduate University of {4. academy of {2., beijing 10003., China 4. beijing Research Institute of Uranium Geology, beijing 100875, China 5. Institute of Geographic {2. and Natural Resources Research, {4. academy of {2., beijing 100101, China 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China 2. Geography and Environment College Jiangxi Normal University 330027 Nanchang China 3. Graduate University of chinese academy of {2. 100039 Beijing China 4. beijing Research Institute of Uranium Geology 100875 Beijing China 5. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

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 3.raduate school of the chinese academy of {2., beijing 10003., China Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate school of the chinese {2. of {3.{4. 10003. 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 3.9 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 4.7 and 4.9 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 4.6 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.

Response synchronization: New progress in brain-visual information processing

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chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , Institute of Atmospheric Physics , chinese academy of {2. , {3. 10002., China 2. Commission of the National Natural Science Foundation of China , {3. 100083. China 3. The Center of Information Science , Peking University, {3. 100871, China 4. Open Laboratory of Visual Information Processing , Institute of Biophysics , chinese academy of {2. , {3. 100101, China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of China Beijing China The Center of Information Science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Improvement of the SLP simulation in the coupled AGCM-ocean surface wave model

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chinese Science Bulletin 2005年第20期50卷 2397-2400页

作者： YU Weidong1, 2. 3. LI Zhaoxin4.& YUAN Yeli3.1. Institute of Oceanology, chinese {4. of {2., Qingdao 2.6071, China 2. Graduate school of chinese {4. of {2., beijing 10004., China 3. Laboratory of Marine Science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061, China 4. LMD/CNRS, Univ. Paris 6, Paris, France Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate school of chinese {2. of {3. Beijing 100049 China Laboratory of Marine Science and Numerical Modeling First Institute of Oceanography State Oceanic Administration Qingdao 266061 China LMD/CNRS Univ. Paris 6 Paris France

The coupled atmosphere-ocean general circulation models (CGCM) are nowbecoming the indispensable tools for the climate study. However, most models still suffer fromunrealistic simulations. One problem is the troublesome climate drift. It may come from someunresolved aspects. One possibility is the poor air-sea surface flux description now adopted inCGCM. The commonly used solution for this problem is the so-called flux correction. To deal with it,Hasslemann proposed an alternative solution of prospect. That is to incorporate the ocean surfacewave model into this coupled GCM system so as to establish a coupled atmosphere-wave-ocean *** necessity is clearly seen from the recent field experiment that air-sea momentum flux dependsstrongly on the sea state. So the explicit calculation of the air-sea flux with the aid of the oceansurface wave model is highly desired. Theoretical progress has provided feasibility to such ideaand experiments have been conducted. Recent work also reveals that coupling ocean surface wave modelwith oceanic general circulation model can result in much better reproduction of the upper oceanthermal structure. This further strengthens our belief in the final realization of the coupledatmosphere-wave-ocean modeling system.

关键词：大气海洋循环模式气象学 SLP模拟