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Criteria for defining and recognizing the various orders of sequences in outcrop sequence stratigraphy

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Science china earth sciences 2004年第7期47卷 618-629页

作者： WANG Xunlian Faculty of earth sciences and Mineral Resources, china university of Geosciences, Beijing 100083, china State Key Laboratory of Palaeobiology and Stratigraphy, nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, nanjing 210008, china 1. Faculty of earth sciences and Mineral Resources China University of Geosciences 100083 Beijing China 2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

The regional distribution in different depositional facies belts is here regarded as an important criterion for defining and recognizing the various orders of sequences. The third-order sequence is possibly global in nature, which may be discerned in different depositional facies belts in one continental margin and can be correlated over long distances, sometimes even worldwide. Commonly, correlation of subsequence (fourth-order sequence with time interval of 0.51.5 Ma) is difficult in different facies belts, although some of them may also be worldwide in distribution. A subsequence should be able to discern and correlate within at least one facies belt. The higher-order sequences, including microsequence (fifth-order sequence) and minisequence (sixth-order sequence), are regional or local in distribution. They may reflect the longer and shorter Milankovitch cycles respectively. Sequence and subsequence are usually recognizable in different facies belts, while microsequence and minisequence may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits. A brief discussion is made on the essential conditions for correct identification of sequences, useful methods of study, and problems meriting special attention in outcrop sequence stratigraphy.

关键词： outcrop sequence stratigraphy, facies belt, sequence, subsequence, microsequence, minisequence, meter-scale cyclothem, Milankovitch cycle.

CHALLENGES AND PROBLEMS: china'S URBAN GOVERNANCE

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Chinese Geographical Science 2002年第2期12卷 152-156页

作者： WANG Hong, GU Chao lin(department of Urban and Resources sciences, nanjing university, nanjing 2.0093, P.R.china) department of Urban and Resources sciences Nanjing University Nanjing 210093 P. R. China

china′s urban reforms have brought social progress and development, but a comprehensive national system of social welfare (for example, unemployment insurance, pensions, medical care and public housing) for new migrants from rural areas is lacking. One of the most remarkable changes in Chinese cities in the last decade was a change in social "equality", with the rise of new poverty both in individual communities and some social groups in urban society. However, there is little social assistance and public infrastructure for the migrants. Governments or communities or individual should pay attention to the control of new urban poverty and new slums. This paper consider that it is necessary to launch a successful policy, which include mainly: 1) accommodating urban growth through low cost investment projects; 2) urban economy depends heavily on successful macroeconomic policy; 3) to broaden the three channels linking adjustment to the incidence of urban poverty; 4) to restructure urban economic based on the high or new technology; 5) to coordinate relationship between urban economic growth and environment management for sustainable development of Beijing′s metropolitan fringe.

关键词： urban challenges and problems urban governance urban policies

Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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Science china(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2 1 department of Materials Science and Engineering,nanjing university of Science and Technology,nanjing 210094,china 2 College of Materials Science and Engineering,Southeast university,nanjing 211189,china 1. department of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

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 2.0093, 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

Completely regular paracompact reflection of locales

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Science china Mathematics 2006年第6期49卷 820-826页

作者： HE Wei & LUO Maokang department of Mathematics, nanjing Normal university, nanjing 210097, china department of Mathematics, Sichuan university, Chengdu 610064, china department of Mathematics Nanjing Normal University Nanjing 210097 China department of Mathematics Sichuan University Chengdu 610064 China

We give an explicit construction of the completely regular paracompact reflection pL of a completely regular locale L described as a sublocale of the Stone-tech compactification βL of L.

关键词： completely regular paracompact locale, nucleus.

Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

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Progress in Natural Science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,Lu Yao b,Hong Yang b a department of earth sciences,nanjing university,nanjing 2.0093,china b College of Resource and Environmental Engineering,Guizhou university(Caijiaguan Campus),Guiyang 550003,china c nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,nanjing 210008,china [a]department of earth sciences Nanjing University Nanjing 210093 China [b]College of Resource and Environmental Engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China [c]Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12th and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation

The Lanshantou Kyanite-bearing Eclogite with Coesite Inclusions in the Sulu Ultrahigh-Pressure Metamorphic Belt and Its PTt Path

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 409-420页

作者： HU Shouxi, SUN Jinggui, LING Hongfei, YE Ying, Fang Changquan and ZHAO Yiying department of earth sciences, nanjing university, nanjing 210008, Jiangsu department of earth sciences, Zhejiang university, Hangzhou 310027, Zhejiang department of earth sciences Zhejiang University Hangzhou 310027 Zhejiang [?]3Hu Shouxi Born in 1929 graduated from Zhejiang university in 1952 now professor of geoscience at nanjing university. His main research interests are mineral deposits and petrology. E-mail: hushouxi@***.

Coesite inclusions are found in kyanite from the Lanshantou eclogite in the Sulu ultrahigh-pressure (UHP) metamorphic belt. This discovery extends the stable region of kyanite to over 2.4 GPa. As an important UHP metamorphic belt in china, the Sulu eclogite belt is the product of A-subduction induced by strong compression of the Yellow Sea terrane to the Jiaodong-northereastern Jiangsu terrane during the interaction of the Eurasian plate and Palaeo-Pacific plate in the Indosinian. It stretches about 350 km and contains over 1000 eclogite bodies. Most eclogites in this belt belong to Groups B and C in the classification of Coleman et al., and commonly contain kyanite, while the Lanshantou eclogite belongs to Group A and contains coesite. The MgO, CaO and FeO contents in garnet and pyroxene show regular variation from the core to the rim, which reveals the PTt paths of progressive metamorphism during the Early Mesozoic (240-200 Ma) and retrogressive metamorphism during the Late Mesozoic and Cenozoic exhumation.

关键词： coesite-bearing kyanite eclogite ultrahigh-pressure (UHP) metamorphic belt PTt path of subduction and exhumation

Diophantine vectors in analytic submanifolds of Euclidean spaces

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Science china Mathematics 2007年第9期50卷 1334-1338页

作者： Rong-mei CAO~(1+) Jian-gong YOU~2 1 College of Science,nanjing university of Aeronautics and Astronautics,nanjing 210016,china 2.department of Mathematics,nanjing university,nanjing 2.0093,china 1. College of Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 China 2. department of Mathematics Nanjing University Nanjing 210093 China

Let $\mathcal{M}$ be an m-dimensional analytic manifold in ? n . In this paper, we prove that almost all vectors in $\mathcal{M}$ (in the sense of Lebesgue measure) are Diophantine if there exists one Diophantine vect... 详细信息

关键词： diophantine vector analytic submanifold 32C05

Exploration of Water Resource and Multiple Model for Water Resource Development in Karst Areas with the Preferred Plane Theory

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 129-135页

作者： LUO Guoyu, YAN Changhong, LI Xiaozhao, JIANG Jianping and MA Ji department of earth sciences, nanjing university, nanjing, Jiangsu 2.0093 department of earth sciences Nanjing University Nanjing Jiangsu 210093

According to the theory of preferred plane, preferred planes (faults) alwayscontrol the distribution of bedrock fissure water and hold abundant groundwater. Thus, theexploration of fissure or karst water can be converted into searching for the watery preferred plane(WPP). In the paper, the characteristic of watery preferred planes is analyzed and a series ofsuperior indices has been set up. It is introduced that WPPs are determined by the methods ofgeological analysis, superior index and complex geophysical analysis. Meanwhile, new multiple modelfor water resource development in the water-scarce areas of karst mountainous regions are advanced.

关键词： theory of preferred plane karst water multiple model for water resourcedevelopment