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Research on Jiuquan-Jiayuguan-Yumen Region's Dynamic Changing of Urbanization Based on Self-Organizing Model

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chinese Journal of Population,Resources and Environment 2005年第3期3卷 22-28页

作者： Li Ming 1,2 & Fang Chuanglin 2 1 graduate school of the chinese Academy of sciences, beijing 100039,china 2 Institute of Geographical sciences and Natural Resources Research, CAS, beijing 100101, china graduate school of the chinese Academy of sciences Beijing 100039 China Institute of Geographical sciences and Natural Resources Research CAS Beijing 100101 China

Based on the self-organizing modeling principle in the dissipative structure theory, the paper regards the migration coupling between the regions as the influence factor to create the model of regional urbanization simulation and prediction, which is more practical to simulate the space-time and dynamic evolvement characteristics of regional urbanization level. According to the historical data about the population and urbanization of Jiuquan, Jiayuguan andYumen cities, the past 50 years' dynamic evolvement trend is simulated and the following 50 years' dynamic evolvement trend is predicted with the urbanization dynamic evolvement model based on the self-organizing model. The analysis of effective factors such as economic increase, resources exploitation, ecosystem construction, traffic location, national policies, population migration are given, then the reasons of the dynamic evolvement differences of the three cities' urbanization are drawn. The study suggests that the self-organizing model is fit for the simulation of Jiuquan-Jiayuguan-Yumen regional urbanization level in the past 50 years, and the departure between the stimulant and the actual data is under 5%, so it can be used to predict the urbanization future of the three cities. The predicted results show that the regional population will reach 1.074 million and the regional urbanization level will be 72.56%.

关键词： self-organizing urbanization dynamic evolvement Jiuquan-Jiayuguan-Yumen region

A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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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 sciences, beijing 100029, china 2. graduate school of the chinese Academy of sciences, beijing 100039, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate school of the chinese Academy of sciences Beijing 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： subsurface runoff parameterization, Boussinesq-storage equation, water storage and recharge.

Contributions of phosphatase and microbial activity to internal phosphorus loading and their relation to lake eutrophication

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Science china Earth sciences 2006年第Z1期49卷 102-113页

作者： SONG Chunlei, CAO Xiuyun, LI Jianqiu, LI Qingman, CHEN Guoyuan & ZHOU Yiyong Institute of Hydrobiology, chinese Academy of sciences, Wuhan 430072, china graduate school of the chinese Academy of sciences, beijing 100039, china Institute of Hydrobiology Chinese Academy of Sciences Wuhan China graduate school of the chinese Academy of sciences Beijing China

Phosphatase may accelerate the process of lake eutrophication through improving phosphorus bioavailability. This mechanism was studied in three chinese eutrophic shallow lakes (Lake Taihu, Lake Longyang and Lake Lianhua). Phosphatase activity was related to the concentration of soluble reactive phosphorus (SRP) and chlorophyll a. Stability of dissolved phosphatase in reverse micelles may be attributed to molecular size, conformation and active residues of the *** the site with Microcystis bloomed in Lake Taihu, dissolved phosphatase activity was higher and more stable in micelles, SRP concentrations were lower in interstitial water, the contents of different forms of phosphorus and the amounts of aerobic bacteria were lower while respiration efficiency was higher in sediments. Phosphobacteria, both inorganic and organic and other microorganisms were abundant in surface water but rare in sediments. Therefore, internal phosphorus may substantially flux into water column by enzymatic hydrolysis and anaerobic release, together with mobility of bacteria,thereby initiating the bloom. In short, biological mechanism may act in concert with physical and chemical factors to drive the internal phosphorus release and accelerate lake eutrophication.

关键词： dissolved phosphatase, reverse micelle, internal loading, phosphorus form of sediment, microbiology, eutrophication, Microcystis bloom.

Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science china Earth sciences 2004年第8期47卷 710-719页

作者： FAN Chengxin1, ZHANG Lu1,2, QIN Boqiang1, WANG Sumin1, HU Weiping1 & ZHANG Chen1 1. Taihu Lake Laboratory for Ecosystem Research, Nanjing Institute of Geography & Limnology, chinese Academy of sciences, Nanjing 210008, china 2. graduate school of chinese Academy of sciences, beijing 100039, china Taihu Lake Lab. for Ecosystem Res. Nanjing Inst. of Geography/Limnology Chinese Academy of Sciences Nanjing 210008 China Grad. Sch. of chinese Acad. of Sci. Beijing 100039 China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.44 t·a-1 loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 425.8 t·a-1, which is equal to 15.0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.

Stochastic dynamic model of SARS spreading

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chinese Science Bulletin 2003年第13期48卷 1287-1292页

作者： SHI Yaolin Computational Geodynamics Laboratory of graduate school of chinese Academy of sciences, beijing 100039, china (e-mail: shiyl@***) Computational Geodynamics Laboratory of graduate school of chinese Academy of sciences 100039 Beijing China.

Based upon the simulation of the stochastic process of infection, onset and spreading of each SARS patient, a system dynamic model of SRAS spreading is constructed. Data from Vietnam is taken as an example for Monte Carlo test. The preliminary results indicate that the time-dependent infection rate is the most important control factor for SARS spreading. The model can be applied to prediction of the course with fluctuations of the epidemics, if the previous history of the epidemics and the future infection rate under control measures are known.

关键词： SARS 非典型肺炎随机过程传染病模型疫情控制

Overexpression of a tobacco small G protein gene NtRop1 causes salt sensitivity and hydrogen peroxide production in transgenic plants

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Science china(Life sciences) 2008年第5期51卷 383-390页

作者： CAO YangRong1,2, LI ZhiGang1,2, CHEN Tao1,2, ZHANG ZhiGang1, ZHANG JinSong1 & CHEN ShouYi1 1 National Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, chinese Academy of sciences, beijing 100101, china 2 graduate school of chinese Academy of sciences, beijing 100039, china National Key Lab of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China graduate school of chinese Academy of sciences Beijing China

The small GTPases of Rop/Rho family is central regulators of important cellular processes in plants. Tobacco small G protein gene NtRop1 has been isolated; however, its roles in stress responses were unknown. In the present study, the genomic sequence of NtRop1 was cloned, which has seven exons and six introns, similar to the Rop gene structure from Arabidopsis. The NtRop1 gene was constitutively expressed in the different organs whereas the other six Rop genes from tobacco had differential expression patterns. The expression of the NtRop1 gene was moderately induced by methyl viologen, NaCl, and ACC treatments, but slightly inhibited by ABA treatment, with no significant induction by NAA treatment. The transgenic Arabidopsis plants overexpressing the NtRop1 showed increased salt sensitivity as can be seen from the reduced root growth and elevated relative electrolyte leakage. The hydrogen peroxide production was also promoted in the NtRop1-trangenic plants in comparison with wild type plants. These results imply that the NtRop1 may confer salt sensitivity through activation of H2O2 production during plant response to salt stress.

关键词： small G protein NtRop1 salt sensitive hydrogen peroxide

Transformations and non-degenerate maps

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Science china Mathematics 2005年第Z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, Academy of Mathematics and System sciences, chinese Academy of sciences, beijing 100080, china graduate school, chinese Academy of sciences, beijing 100080, china Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

A NOTE ON THE CONSISTENCY OF LS ESTIMATES IN LINEAR MODELS

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chinese Annals of Mathematics,Series B 2001年第4期22卷 471-474页

作者： CHEN XIRU The graduate school at beijing, University of Science and Technology of china, beijing 100039, china. The graduate school at beijing University of Science and Technology of China Beijing 100039 China

It is well known that when the random errors are iid. with finite variance, the week and the strong consiStency of LS estimate of multiple regression coefficients are equivalent. This note, by constructing a counter-example, shows that this equivalence no longer holds true in case that the random errors possess only the r-th moment with 1≤5 T ＜ 2.

关键词：相容性线性回归模型最小二乘估计有限方差

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese Academy of sciences, beijing 100049 2 graduate school of chinese Academy of sciences, beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school of chinese Academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general