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Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

Science china(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2,GONG JianYa3.& WANG YingYing4 1 Institute of Geophysics and Geomatics,china university of geosciences,{3. 43.074,china 2 Department of Geography,Hong Kong Baptist university,Hong Kong 3.State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,{3. university,{3. 43.074,china 4 Hubei Provincial Bureau of Meteorology,{3. 43.074,china 1. Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China2. Department of Geography Hong Kong Baptist University Hong Kong China3. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430074 China4. Hubei Provincial Bureau of Meteorology Wuhan 430074 China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

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On the Symmetry Classes of Functions

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wuhan university Journal of Natural Sciences 2005年第5期10卷 813-816页

作者： ZHU Ping~1,2, FAN Yun~3.1. School of Mathematics and Statistics, wuhan university, wuhan 43.072, Hubei,{3. 2. School of Science, Beijing university of Posts and Telecommunications, Beijing 100876,{3. 3. School of Mathematics and Statistics, Huazhong Normal university, wuhan 43.079, Hubei,{3. wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Beijing university of Posts and Telecommunications School of Science Beijing China (GRID:grid.31880.32) Huazhong Normal university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.411407.7) (ISNI:***)

Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes.

关键词： symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent

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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab Center, china university of geosciences (Beijing), Beijing 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, Peking university, Beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

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Science china Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3.& CHENG Hai4 1. Faculty of Earth Science,china university of geosciences,{3. 43.074,china 2. School of Environmental Studies,china university of geosciences,{3. 43.074,china 3. SKLLQG,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china 4. Department of Geology and Geophysics,university of Minnesota,MN55455,USA 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. School of Environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

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The Upper Devonian orbital cyclostratigraphy and numerical dating conodont zones from Guangxi,South china

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Science china Earth Sciences 2005年第1期48卷 32-41页

作者： GONG Yiming, XU Ran, TANG Zhongdao & LI Baohua Faculty of Earth Science, china university of geosciences,{3., china Laboratory of Marine Geology, Tongji university, Shanghai 200092, china 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. Laboratory of Marine Geology Tongji University 200092 Shanghai China

The hierarchically organized laminae, bundles, bundlesets and superbundlesets which correspond to a sub-Milankovitch, obliquity or precession, eccentricity and long eccentricity cyclothems, respectively, have been distinguished from the Upper Devonian Fras-nian-Famennian (F-F) transitional carbonate successions deposited in the carbonate-basin and slope facies of Guangxi, South china. The durations of cyclothems are 8000-10000a, 16667a or 3.3.3., 100000a and 400000a, respectively. The ratio of eccentricity to precession, eccentricity to obliquity, and long eccentricity to eccentricity is 1 : 6, 1 : 3.and 1 : 4 in the Devonian, respectively. Orbital cyclostratigraphical studies show that the durations of the conodont falsio-valis Zone, transitans Zone, punctate Zone, Lower hassi Zone, Upper hassi Zone, jamieae Zone, Lower rhenana Zone, Upper rhenana Zone, linguiformis Zone, Lower triangularis Zone, Middle triangularis Zone and Upper triangularis Zone are 0.4, 0.4, 0.4, 0.3. 0.4, 0.2, 0.8, 0.6, 0.8, 0.3. 0.3.and 0.3.Ma from bottom to top, respectively, and the duration of the Frasnian is 4.3.Ma. The conodont is the normal marine organism of the latest mass extinction (the latest linguiformis Zone) and the first recovery (including the whole Lower triangularis and Middle triangularis Zone) in the F-F transition. The conodont mass extinction and recovery lasted 200000-100000a and 0.6 Ma, respectively. We consider that average durations of the fossil zones calculated by reported numerical ages divided by fossil zone numbers within a stage or series or system cannot discovery complications and non-uniformity of evolutionary organisms and environments.

关键词： orbital cyclostratigraphy, conodont zone, numerical dating, mass extinction, Devonian, Guangxi, South china.

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Fault System,Deformation Style and Development Mechanism of the Bachu Uplift,Tarim Basin

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Journal of Earth Science 2012年第4期23卷 529-541页

作者：佟殿君张俊霞阳怀忠胡德胜任建业 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences School of Economics and Management China University of Geosciences Beijing Research Institute CNOOC Zhanjiang Branch CNOOC Structral Research Center of Oil&Gas Bearing Basin Ministry of EducationChina University of Geosciences

The Bachu （巴楚） uplift is one of the most active tectonic regions nowadays in the Tarim basin, which is also a faulted block uplift that was intensively active during the Cenozoic. This study was based primarily on the geological structure interpretation of seismic profiles, applying the theories and methods of basin dynamics, structural analysis and tectono-stratigraphic analysis, the geometry and kinematics features of the fault systems in the Bachn uplift were analyzed in detail. Our study shows that each fault belt is mainly characterized by compression and overthrusting, most of the faults initiated and activated during the Mid-Late Himalayan period, and that the general structural styles of the Bachu uplift were basement-involved pop-up thrust faulted block uplift, of which the southern margin was covered by the large-scale decollement fault system. The basement-involved structures widely developed in the higher position of the basement uplift, while decollement fault system developed mainly at the position with gypsum mudstone. The evolution process of Bachu uplift included back-bulge slope of the peripheral foreland basin in Mid-Late Caledonian, forebulge in HercynianYanshanian and the latest compressional faulted block uplift in Mid-Late Himalayan. Meanwhile,the study also suggests that the formation, reconstruction and stabilization of the uplift were controlled by the development and evolution of fault systems clearly. In the early forebulge stage, it was mainly presented as flexural deformation without the developing of thrust faults in the Bachu area; to the late stage, under the influence of violent lateral compression deformation, the faulted block uplift formed finally.

关键词： fault system structural style structural evolution Bachu uplift Tarim basin.

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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences,{3., china 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 454003. china 3. Department of Computer Science, South-Central university for Nationalities,{3., china 4. Laboratory of Marine Geology, Tongji university, Shanghai 200092, china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china university of geosciences {3. china Institute of Resources & Environments Henan Polytechnic university Jiaozuo china Department of Computer Science South-Central university for Nationalities wuhan china Laboratory of Marine Geology Tongji university Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

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Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3. ZHOU Su3. LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3.1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 10003., china 2. Development and Research Center, china Geological Survey, Beijing 10003., china {3., Beijing 100083. china 4. china university of geosciences, wuhan 43.074, china 5. Information Center of Ministry of Land and Resources, Beijing 100812, china 6. Institute of Geology, State Seismological Bureau, Beijing 100029, china 1. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china university of geosciences 100083 Beijing China 4. china university of geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. Institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

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Flame-retardant Mechanism of Magnesium Oxychloride in Epoxy Resin

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Journal of wuhan university of Technology(Materials Science) 2009年第1期24卷 127-131页

作者：秦麟卿 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Center for Material Research and Analysis Wuhan University of Technology

Flame-retardant mechanism of magnesium oxychloride （M OC） in EP was in-vestigated by limiting oxygen index （LOI）, XRD, SEM, TG-DTG and DSC. The results show that MOC performed well as an inorganic flame-retardant in EP. When the content of MOC is 50%, the LOI of EP reaches 29.6% and mass of residual char reaches 9.6%. The flame retarde mechanism of MOC is due to the synergies of diluting, cooling, catalyzing char forming and obstructing effects.

关键词： magnesium oxychloride epoxy resin flame-retardant properties flame retardedmechanism

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Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of wuhan university of Technology(Materials Science) 2006年第4期21卷 146-149页

作者：霍凯成 Hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

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