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HIGH RESOLUTION SCB SCHEME FOR HYPERBOLIC SYSTEMS OF 2-D CONSERVATION LAWS

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Journal of Computational Mathematics 1998年第2期16卷 179-192页

作者： Ning Zhao (department of Aerodynamics, nanjing university of Aeronautics and Astronautics, nanjing 210016, china) nanjing Univ Aeronaut & Astronaut Dept Aerodynam Nanjing 210016 Peoples R China

In this paper, a new class of high resolution schemes satisfying the 'condition A' (SCA) and the 'condition B' (SCB) for hyperbolic systems of conservation laws in one and two dimensions are constructed. Moreover, the results of the numerical experiments by using these schemes are given for the system of Euler equations in one and two dimensions.

关键词： SCB scheme hyperbolic system conservation law

Classification and Source Materials of Continental Crust Transformation Series Granitoids in South china

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 287-298页

作者： Liu Changshi Zhu Jinchu Shen Weizhou Xu Shijin department of earth sciences, nanjing university, nanjing, Jiangsu Jiang Minxi department of earth sciences Nanjing University Nanjing Jiangsu

The granitoids of the continental crust transformation series in South china may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollision type. Based on the results of Sr and Nd isotopic determinations, the source material compositionof the three types of granitoids is calculated with crust-mantle binary mixing simulation. The calculations indi-cate that the granitoids of the first type consist of 78.6-89.7% upper crust endmember materials and15.0-10.3% depleted mantle endmember materials, the granitoids of the second type are composed of 63.7%upper crust endmember materials and 36.3% depleted mantle endmember materials, and those of the third type100% upper crust endmember materials. Hence. the source material composition of the granitoids of all thethree types is dominated by upper crust endmembers.

关键词： Classification and Source Materials of Continental Crust Transformation Series Granitoids in South china Source

More on Bounding Introspection in Modal Nonmonotonic Logics

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Acta Mathematica Sinica,English Series 2000年第4期16卷 555-564页

作者： Xishun Zhao Decheng Ding department of Mathematics. nanjing university. nanjing 210093, P. R. china department of Mathematics Nanjing University Nanjing 210093 P. R. China

By L. we denote the set of all propositional fornmlas. Let C be the set of all clauses. Define C_n=C(Lη:η∈C}.In Sec. 2 of this paper. we prove that for normal modal logics S, the notions of (S. C_)-expansions and S-expansions coincide. In Sec. 3. we prove that if I consists of default clauses then the notions of S-expansions for I and (S.C)-expansions for I coincide. To this end. we first show. in Sec *** the notion of S-expansions for I is the same as that of (S.L)-expansions for I.

关键词： Modal nonmonotonic logic Expansion Bounding Introspection Default clause

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. department of Geography, nanjing university, nanjing 210093, china 3. School of earth sciences and Resources, china university of Geosciences, Beijing 100083, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China department of Geography Nanjing University Nanjing 210093 China School of earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

MEASUREMENT OF NUMBER AVERAGE MOLECULAR WEIGHT OF STYRENE OLIGOMER BY ^(13)C-NMR METHOD

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Chinese Journal of Polymer Science 1999年第2期17卷 135-140页

作者： Song Wang Xiao-hu Yan Rong-shi Cheng department of Polymer Science and Engineering, nanjing university, nanjing 210093, china department of Polymer Science and Engineering Nanjing University Nanjing 210093 China

^(13)C-NMR ~1H-decoupled spectra of styrene polymers were assigned by comparison with modelcompounds, then used in measurements of number average molecular weights. The higher limit of an exactdetermination of the end group signal is less than a molecular weight of 10~4. For polymer samples withM_n3, the results obtained from ^(13)C-NMR spectra of saturated carbon region are in excellent agreementwith the values determined by ~1H-NMR, SEC, and VPO methods, while the results from ^(13)C-NMR spectra ofphenyl C-1 carbon region are somewhat higher than the values determined by other methods.

关键词： Molecular weight measurement Styrene oligomer ^(13)C-NMR spectra

Maschke-type theorem and Morita context over weak Hopf algebras

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Science china Mathematics 2006年第5期49卷 587-598页

作者： ZHANG Liangyun College of Science, nanjing Agricultural university, nanjing 210095, china department of Mathematics, nanjing university, nanjing 210008, china 1. College of Science Nanjing Agricultural University Nanjing 210095 China 2. department of Mathematics Nanjing University Nanjing 210008 China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

Polymer-assisted nanoparticulate contrast-enhancing materials

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Science china Chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2,WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic Chemistry and department of Polymer Science and Engineering,College of Chemistry & Chemical Engineering,nanjing university,nanjing 210093,china 2National Laboratory of Solid State Microstructure,department of Material Science and Engineering,nanjing university,nanjing 210093,china 3Key Laboratory of Analytical Chemistry for Life Science,Ministry of Education,School of Chemistry and Chemical Engineering,nanjing university,nanjing 210093,china 1. Laboratory of Mesoscopic Chemistry and department of Polymer Science and Engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing 210093 China3. Key Laboratory of Analytical Chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing 210093 China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

Global dimension and left derived functors of Hom

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Science china Mathematics 2007年第6期50卷 887-898页

作者： Li-xin MAO & Nan-qing DING Institute of Mathematics, nanjing Institute of Technology, nanjing 211167, china department of Mathematics, nanjing university, nanjing 210093, china 1. Institute of Mathematics Nanjing Institute of Technology Nanjing 211167 China 2. department of Mathematics Nanjing University Nanjing 210093 China

It is well known that the right global dimension of a ring R is usually computed by the right derived functors of Hom and the left projective resolutions of right R-modules. In this paper, for a left coherent and right perfect ring R, we characterize the right global dimension of R, from another point of view, using the left derived functors of Hom and the right projective resolutions of right R-modules. It is shown that rD(R) ? n (n ? 2) if and only if the gl right Proj-dim M R ? n?2 if and only if Ext n?1(N,M) = 0 for all right R-modules N and M if and only if every (n?2)th Projcosyzygy of a right R-module has a projective envelope with the unique mapping property. It is also proved that rD(R) ? n (n ? 1) if and only if every (n?1)th Proj-cosyzygy of a right R-module has an epic projective envelope if and only if every nth Proj-cosyzygy of a right R-module is projective. As corollaries, the right hereditary rings and the rings R with rD(R) ? 2 are characterized.

关键词： global dimension projective resolution envelope 16E10 16E30 16E05

Lipschitz classes on local fields

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Science china Mathematics 2007年第7期50卷 1005-1014页

作者： Wei-yi SU~(1+) Guo-xiang CHEN~2 1 department of Mathematics,nanjing university,nanjing 210093,china 2 department of Mathematics,nanjing Audit university,nanjing 211815,china 1. department of Mathematics Nanjing University Nanjing 210093 China 2. department of Mathematics Nanjing Audit University Nanjing 211815 China

The Lipschitz class Lipαon a local field K is defined in this note,and the equivalent relationship between the Lipschitz class Lipαand the Holder type space C~α(K)is ***,those important characteristics on the Euclidean space R^n and the local field K are compared,so that one may interpret the essential differences between the analyses on R^n and ***,the Cantor type fractal functionθ(x)is showed in the Lipschitz class Lip(m,K),m＜(ln 2/ln 3).

关键词： local field Holder type space Lipschitz class Cantor type fractal function 11F85 46F05 43A25 28A80 28A78