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Chinese Science Bulletin 2001年第S1期46卷 45-51页

作者： WANG Lachun & ZHANG Yongzhandepartment, of urban & Resource {2., nanjing university, nanjing 210093, china Key Laboratory of Coast & Island Development of Ministry of Education of china, nanjing university, nanjing 210093, china 1. department of Urban & Resource Sciences Nanjing University 210093 Nanjing China 2. Key Laboratory of Coast & Island Development of Ministry of Education of china Nanjing University 210093 Nanjing China

Conduit flow is a special geomorphologic and hydrological phenomenon in karst area. Houzhai River drainage basin in Puding, Guizhou Province is a large-scale test field in the main and broad karst area in the southern part of china, where conduit flow is a general reserve and drainage system for groundwater. Based on the great deal of field investigation and indoor research work during the 1970s-1980s, pulse tests were done four times there during 1988-1991 in wet and dry seasons. It shows that water level at each observation site changes from 10 to 1800 mm, with the larger variation in upper stream and at karst windows than in lower reaches and at each exit along subterraneous rivers. The average flow velocity in conduit system is determined within 2.0-800 m/h, with the less change from flood to dry seasons, and it is higher in principal conduits and in upper stream area. Also, the reliable divided discharge ratio among each hydrological conduit of sunken system has been got. Thus, combined with

关键词： conduit flow karst pulse test Houzhai River.

A CASE STUDY ON CONCENTRATION AND DECENTRALIZATION:BEHAVIOR AND DYN AMIC MECHANISM OF SPATIAL EVOLUTION IN METROPOLITAN AREA,nanjing,china

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Chinese Geographical Science 2002年第3期12卷 212-217页

作者： ZHU Xi-gang,ZHANG Jing-xiang,CHEN Hu (department of urban and {2. sciences,nanjing university,Nanjin g 210093,P.R.china,) department of urban and {2. sciences Nanjing University Nanjing P. R. China

In rapid socio-economic developme nt,the process of concentration and dispersal of various elements tends to be more dramatic,tremendously in fluencing the shaping and transform ation of the space in metropolitan *** of spatial concentration and decent ralization has thus become a basic me thod in examining metropolitan spatial *** this research,three elements were selected as the essential indicato rs of the process:demographic density distribu-tion,employment density distribut ion and business office *** of these elements in Nanji ng City was exam-ined *** nanjing City c ould be regarded as a representative of metropolitan areas in china,its s ituation large-ly suggestes the general characteristics in similar areas of *** based on the investigation of Nanji ng City,four general implications were highligh ***,metropolitan areas in{2. are in a violentprocess and shift of spatialconcentra-tion and ***,from now to at least the near future,c oncentration will continue to be the central ***,the landscape of metrop olitan areas basically exhibits a dual structure *** gap in en vironmental and ecological qualities among different districts will continue for a l ong ***,Central Business District(CBD)is playing an important role in helpi ng to convert the traditionally single-centered city structure into a polycentric one.

关键词： concentration decentralization dynamic mechanism nanjing metropolis

SOLVING TRUST REGION PROBLEM IN LARGE SCALEOPTIMIZATION

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Journal of Computational Mathematics 2000年第1期18卷 1-12页

作者： Bing-sheng He(department of Mathematics, nanjing university, Naming {2., china) 南京大学江苏南京 210093

Presents a study which introduced a method for solving trust region problem in scale minimization. Review of the conjugate gradient method (CG) and the projection and contraction (PC) method; Convergence behavior of t... 详细信息

关键词： trust region problem conjugate gradient method projection and contraction method

Binomial coefficients,Catalan numbers and Lucas quotients

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Science china Mathematics 2010年第9期53卷 2473-2488页

作者： SUN ZhiWei department of Mathematics,nanjing {2.,nanjing 210093,china 1. department of Mathematics Nanjing University Nanjing 210093 China

Let p be an odd prime and let a,m ∈ Z with a > 0 and p ︱ *** this paper we determinep ∑k=0 pa-1(2. k=d)/mk mod p2.for d=0,1;for example,where(-) is the Jacobi symbol and {un}n≥0 is the Lucas sequence given by u0 = 0,u1 = 1 and un+1 =(m-2.un-un-1(n = 1,2.3,...).As an application,we determine ∑02.for any integer r,where Ck denotes the Catalan number 2.k /(k + 1).We also pose some related conjectures.

关键词： congruences binomial coefficients Catalan numbers Lucas quotients

On contactomorphism group of contact structure overtwisted at infinity on R^3

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Science china Mathematics 2007年第8期50卷 1087-1092页

作者： Li YU department of Mathematics,nanjing {2.,nanjing 210093,china department of Mathematics Nanjing University Nanjing 210093 China

We compute all the homotopy groups of the compactly supported contactomorphism group of a contact structure on R^3 which is overtwisted at infinity.

关键词： contactomorphism overtwisted contact structure

THE SECOND EXPONENT SET OF PRIMITIVE DIGRAPHS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 233-236页

作者： MIAO ZHENGKE(department of Mathematics, nanjing university,{2., china.)(department of Mathematics, Xuzhou Normal university, Xuzhou 2.1009, china.) ZHANG KEMIN(department of Mathematics, nanjing university,{2., china.) department of Mathematics Nanjing University Nanjing 210093 China department of Mathematics Xuzhou Normal University Xuzhou 221009 China

Let D = (V, E) be a primitive digraph. The exponent of D, denoted byγ(D), is the least integer k such that for any u, v∈ V there is a directed walk of length k from u to v. The local exponent of D at a vertex u∈ V, denoted by exp_D (u), is the least integer k such that there is a directed walk of length k from u to v for each v ε V. Let V = {1,2.….,n}. Following [1], the vertices of V are ordered so that exp_D (1) ≤exp_D (2. ≤…≤exp_D(n) =λ(D). Let E_n(i):= {exp_D (i) ∈D PD_n}, where PD_n is the set of all primitive digraphs of order n. It is known that E_n(n) = {γ(D) D∈PD_n} has been completely settled by [7]. In 1998, E_n(1) was characterized by [5]. In this paper, the authors describe E_n(2. for all n≥2.

关键词： Primitive digraph Local exponent Gap

Effect of quercetin on chronic enhancement of spatial learning and memory of mice

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Science china(Life sciences) 2006年第6期49卷 583-590页

作者： LIU Jiancai1,YU Huqing2.& NING Xinbao1 1. State Key Laboratory of Modern Acoustics,department of Electronics Science and Engineering,Institute of Biological Medical Electronic Engineering,nanjing {2.,nanjing 210093,china 2. department of Biology Science and Technology,nanjing {2.,nanjing 210093,china State Key Laboratory of Modern Acoustics Department of Electronics Science Engineering Institute of Biological Medical Electronic Engineering Nanjing University Nanjing 210093 China department of Biology Science Technology Nanjing University Nanjing 210093 China

In this study we evaluated the effect of quercetin on D-galactose-induced aged mice using the Morris water maze (MWM) test. Based on the free radical theory of aging, experiments were performed to study the possible biochemical mechanisms of glutathione (GSH) level; hydroxyl radical (OH ) in the hippocampus; cerebral cortex; the brain tissue enzyme activity of the mice. The results indicated that quercetin can enhance the exploratory behavior, spatial learning; memory of the mice. The effects relate with enhancing the brain functions; inhibiting oxidative stress by quercetin,; relate with increasing the GSH level; decreasing the OH content. These findings suggest that quercetin can work as a possible natural anti-aging pharmaceutical product.

关键词： quercetin aging learning memory free radical reactive oxygen species (ROS) glutathione (GSH)

Study on the thermal stability and electrical properties of the high-k dielectrics (ZrO_2. _x(SiO_2._(1-x)

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Science china(Technological sciences) 2009年第8期52卷 2222-2226页

作者： Lü ShiCheng1,2. YIN Jiang1,2. XIA YiDong2.3, GAO LiGang2.3 & LIU ZhiGuo2.3 1 department of Physics, nanjing university,{2., china 2.National Laboratory of Solid Sate Microstructures, nanjing university,{2., china 3 department of Materials Science and Engineering, nanjing university,{2., china 1. department of Physics Nanjing University Nanjing 210093 China 2. National Laboratory of Solid Sate Microstructures Nanjing University Nanjing 210093 China 3. department of Materials Science and Engineering Nanjing University Nanjing 210093 China

(ZrO2.x(SiO2.1-x (Zr-Si-O) films with different compositions were deposited on p-Si(100) substrates by using pulsed laser deposition technique. X-ray photoelectron spectra (XPS) showed that these films remained amorphous after annealing at 800℃ with RTA process in N2.for 60 s. The XPS spectra indi- cated that Zr-Si-O films with x=0.5 suffered no obvious phase separation after annealing at 800℃, and no interface layer was formed between Zr-Si-O film and Si substrate. While Zr-Si-O films with x >0.5 suffered phase separation to precipitate ZrO2.after annealing under the same condition, and SiO2.was formed at the interface. To get a good interface between Zr-Si-O films and Si substrate, Zr-Si-O films with bi-layer structure (ZrO2.0.7(SiO2.0.3/(ZrO2.0.5(SiO2.0.5/Si was deposited. The electrical properties showed that the bi-layer Zr-Si-O film is of the lowest equivalent oxide thickness and good interface with Si substrate.

关键词： high-k dielectric film pulsed laser deposition pseudo ternary alloy

Y_CΩ_(2.)are easy terms

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Chinese Science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2.1. department of Mathematics, nanjing university,{2., china 2. Institute of Software, Chinese Academy of sciences, Beijing 100080, china department of Mathematics Nanjing University Nanjing China Institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

Responses of soil nutrient to driving mechanism in Taihu Lake basin in last 2. years

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Journal of Geographical sciences 2001年第1期11卷 92-98页

作者： CHEN Fu, PENG Bu-zhuo, BAO Hao-sheng (department of urban and {2. Science, nanjing university, nanjing 210093, china) nanjing university Department of Urban and Resources Science Nanjing China (GRID:grid.41156.37) (ISNI:***)

The objectives of this study is to understand the changing law of soil nutrient quality in Taihu Lake basin, Yangtze Delta in last 2. years, and reveal the relationship between soil nutrient changes and human driving forces in regional level over long period of time. Experiment on long-term collecting samples was conducted to study changes of soil organic matter, total N, available N, available P and available K in Dongting town, Wuxi city during the last 2. years. The paper analyses the co-relationship of the fluctuation of soil nutrient and state policy, cultivating practice, agricultural input, and per hectare agricultural net income. The results showed that at first the content of soil organic matter increased, then decreased, and increased again. The content of total N and available N steadily increased. The content of available K and available P steadily decreased. The authors found that the influence of state policy and cultivating practice on soil nutrient quality index (SNQI) is obvious, agricultural input and SNQI are positively correlated, and per hectare agricultural net income and SNQI are negatively correlated.

关键词： soil nutrient SNQI human driving mechanism Taihu Lake basin