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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, Wuhan 4.0074. china {4., henan polytechnic University, jiaozuo 4.4.03. china 3. Department of Computer Science, South-Central University for Nationalities, Wuhan 4.0074. china 4. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral resources china University of Geosciences Wuhan china institute of resources & {2. henan {4. 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 13Ccarb and δ 13Ckerogen) from +0.4. (‰ V-PDB) to +3.54.(‰ V-PDB) and from ?2..38 (‰ V-PDB) to ?2..14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3 X 15%)) values from 0.015 to 0.14., TOC values from 0.02. to 0.2.%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.2. to 4..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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Calcite Cements in Burrows and Their Influence on Reservoir Property of the Donghe Sandstone, Tarim Basin, china

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Journal of Earth Science 2012年第2期23卷 129-141页

作者：齐永安王敏郑伟李妲 institute of resources and Environment Henan Polytechnic University Key Laboratory of Biogenic Traces and Sedimentary Minerals of henan Province Henan Polytechnic University

Abundant burrows of Skolithos linearis, Palaeophycus tubularis, and Taenidium barretti are preserved in the Upper Devonian Donghe sandstone of Tarim basin, china. They are commonly highlighted in core by the color of the burrow fill in contrast to the surrounding matrix and have dif-ferent textures and fabrics from the matrix. There are three kinds of calcite cements in burrows, microcrystalline-crystalline calcite cement, mosaic calcite cement, and ferroan calcite cement. Microcrystalline-crystalline calcite cement is widely distributed in the lower part of the Donghe sand-stone, but it is rare in burrows filling. It displays a globule structure under burial cementation and sel-dom replaces the quartz grains in shallow burial depth stage. Mosaiccalcite cement is widespread in the Donghe sansdtone reservoir of North Tarim basin. It shows chrysoidine, orange and bright orange lu-minescence, and intensely replaces the quartz grains, forming in early diagenetic and shallow burial depth stage. Ferroan calcite is asymmetrically distributed in the Donghe sandstone reservoir of Central Tarim basin. It fills the remanent pores in the shape of mosaic and replaces the quartz grains, matrix, and early calcite cement, forming in late diagenetic and deep burial depth stage. The burrows filled with white calcite cements have low oil saturation or may be oil-stained. In contrast, there is high oil saturation in the sandstone reservoir where the bioturbation is sparse or not present. With increased bioturbation, the porosity, permeability, and oil saturation decrease; thus, bioturbation intensity and reservoir property appear to be negatively correlated.

关键词： burrow calcite cement Donghe sandstone reservoir property.

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Rational formulation of modern geoid concept

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中国有色金属学会会刊：英文版 2011年第S3期21卷 675-680页

作者： GUO Zeng-zhang, XIAO Jian-hua Geodesy institute, henan {2. University, jiaozuo 4.4.00, {4. Geodesy institute Henan Polytechnic University Jiaozuo 454000 China

Based on modern geometrical field theory, a rational interpretation of modern geodesic surface concept was formulated. The general equations for geodesic surface were given. The height concept and arc length concept were formulated strictly. Their intrinsic benefits and shortages of parameter-center reference and mass-center reference systems were studied in details. The research results show that the geodesic concept depends on the available technology. The technology-dependence feature of geodesy concept was expressed by related mathematic formulations. For the satellite-based observation system, the rationality of china-2.00 Geoid Reference System was explained. Discussions about how to establish regional precision reference system were made based on general equations of arc length and space distance equations. A new correction item should be taken into consideration for arc length gauge calculation.

关键词： geodesic surface parameter-center system mass-center system geodesy deformation geoid

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Endolithic fungi:A possible killer for the mass extinction of Cretaceous dinosaurs

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Science china Earth Sciences 2008年第6期51卷 801-807页

作者： GONG YiMing1,2. XU Ran1 & HU Bi2.1 Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, State Key Laboratory of Geological Processes and Mineral resources, china University of Geosciences, Wuhan 4.0074. china 2.institute of resources and Environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of henan Province, henan polytechnic University, jiaozuo 4.4.03. china 1. Key Laboratory of Biogeology and Environmental Geology of Ministry of Education State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. institute of resources and Environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of henan Province Henan Polytechnic University Jiaozuo 454003 China

Mycelium-like structures found under ESEM within radial sections of fragmental dinosaur eggshells would be the endolithic fungi coexistent with dinosaur eggs in the upper part of the Late Cretaceous Hugang Formation from the Wenjiaping section of Wenxian, Danjiangkou, northwestern Hubei, Central china. The endolithic fungi selectively occurred in the bad biomineral zone within the columnar layer of the eggshells, where the crowded endolithic fungi penetrated the columnar layer at near-vertical or near-horizontal angles. The endolithic fungi are needle-like, ribbon-like and silk-like, and 5–18 μm long, 0.3–0.5 μm wide at their base, with pointed tip, and are unbranched. The hyphae are mainly composed of oxygen, carbon and calcium, and are with minor sodium, potassium, chlorine and sulfur. The endolithic fungi and host have the same characters in lithification, fracture and main chemical composition. We suggested that the episode endolithic fungi invading dinosaur eggs may have taken place in the interval between after formation of dinosaur eggshells and before their petrification and that dinosaur eggs invaded by endolithic fungi would not be normally incubated or would only be incubated into venerable and pathologic baby dinosaurs to be easily to aborted and contributed to the mass extinction of the dinosaurs at the end of Cretaceous.

关键词： endolithic fungi dinosaur eggs mass extinction Cretaceous

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Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2. ZHANG Yin-ling1, 2. WANG Fei 1 ,2. ZHANG Zhen-hui 3, GUO Yu-xiang1, 2.1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, {4. polytechnic University,{2. 2. School of Surveying and land Information Engineering, {4. polytechnic University,{2. 3. Qingdao Branch of Naval Aeronautical Engineering institute, Qingdao 2.604., china henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

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Weak Morrey spaces and strong solutions to the Navier-Stokes equations

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Science china Mathematics 2007年第10期50卷 1401-1417页

作者： Chang-xing MIAO~(1+) Bao-quan YUAN~2.~1 institute of Applied Physics and Computational Mathematics,P.O.Box 8009,Beijing 100088,china ~2.College of Mathematics and Informatics,{2. polytechnic University,jiaozuo 4.4.00,china 1. institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China 2. College of Mathematics and Informatics Henan Polytechnic University Jiaozuo 454000 China

We consider the Cauchy problem of Navier-Stokes equations in weak Morrey *** first define a class of weak Morrey type spaces M_(p,λ)~*(R^n)on the basis of Lorentz space L_(p,∞)=L_p~*(R^n) (in particular,M_(?)~*(R^n)=L_(p,∞),if p>1),and study some fundamental properties of them;Second, we prove that the heat operator U(t)= e^(tΔ)and Calderón-Zygmund singular integral operators are bounded linear operators on weak Morrey spaces,and establish the bilinear estimate in weak Morrey ***,by means of Kato's method and the contraction mapping principle,we prove that the Cauchy problem of Navier-Stokes equations in weak Morrey spaces M_(p,λ)~*(R^n)(1

关键词： Navier-Stokes equations, weak Morrey spaces, Lorentz spaces, Cauchy problem,time-global well-posedness, self-similar solutions

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Structure and Mechanical Properties of Ni-based Porous Superalloy

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 73-77页

作者：米国发 School of Materials Science and Engineering Henan Polytechnic University

The porous superalloy materials with hollow spherical and oriented linear pores were fabricated by means of powder metallurgy using Ni-based superalloy powders. Structure observation revealed that the pores of the porous material exhibited uniform distribution and the pores were of the same size in principle. The sintering necks created between adjacent particles on metal skeleton after sintering. The porosity of the porous material increased with increasing the addition of pore forming agent, and the hollow spherical porous material with a porosity of 81.62. were obtained when the addition of pore forming agent was 4.%. The compression test indicated that this kind of materials possesses excellent energy absorption capability, and the compression resistance decreased with the increasing of porosity and pore size.

关键词： porous superalloy powder metallurgy hollow spherical pores oriented linear pores

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Microstructure of a Spray Deposited Intermetallic Compound Alloy of Ni-Al-Mo System

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Journal of Wuhan University of Technology(Materials Science) 2010年第3期25卷 375-378页

作者：米国发 institute of Material Physics & Metallurgy Henan Polytechnic University

The microstructure of a spray deposited intermetallic compound alloy of Ni-Al-Mo system（Ni3Al-Mo intermetallic compound alloy） prepared by a spray atomization deposition was studied in detail by using optical metallography,XRD,DTA,SEM,TEM,HREM and computer *** preform consists of uniform and equiaxial grains,ranging from 10-4. μm,with some *** the main phases of the matrix alloy γ＇ and γ,Ni2.o and Ni3Mo phases are also found within the γ network.A new Ni enriched phase in the γ phase was identified to have face-centered cubic structure with a lattice constant α=1.09 nm and space group Fm3m.

关键词： spray atomization co-deposition Ni3Al-Mo superalloy microstructure

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The initial and final state of SNe Ia from the single degenerate model

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1732-1738页

作者： MENG XiangCun1,YANG WuMing1 & LI ZhongMu2.3 1School of Physics and Chemistry,henan polytechnic University,{2. 4.4.00,{4. 2.4. for Astronomy and History of Science and Technology,Dali University,Dali 671003,{4. 3National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012.{4. 1. School of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China2. Institute for Astronomy and History of Science and Technology Dali University Dali 671003 China3. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Although type Ia supernovae(SNe Ia) show their importance in many astrophysical fields,the nature of the progenitors of SNe Ia is still *** present,the single degenerate(SD) model is presented to be a very likely progenitor *** the comprehensive SD model developed by Meng & Yang(2.10),we show the initial and final state of the progenitor systems of SNe Ia in an orbital period—the secondary mass(log Pi,M2.) *** results may explain the location of some supersoft X-ray sources and recurrent novae in the(log Pi,M2.) plane,and be helpful to judge whether an SD system is the potential progenitor system of SNe Ia,as well as to simulate the interaction between SN ejecta and its companion.

关键词： binaries:close stars:evolution supernovae:general white dwarfs

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4. LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, institute of Geographic Sciences and Natural resources Re-search, Chinese Academy of Sciences, Beijing 100101, {2. 2. institute of Forestry, Chinese Academy of Forestry Sciences, Beijing 100091, {2. 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, {2. 4. Eco-environmental Research Center, Chinese Academy of Sciences, Beijing 100085, {2. 5. College of resources and Environment, Southwest Agricultural University, Chongqing 4.0716, {2. Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4. less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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