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A restudy of Oryctocephalus indicus (Reed,1910)

Progress in Natural science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4. and GUO Qingjun~5(1. College of Resource and Environment of Guizhou university, Guiyang 550003, China 2. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 210008, China 3. state Key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 210008, China 4. department of geological science,{4., columbus, oh 432.0, USA 5. Institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, China) College of Resource and Environment of Guizhou university Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China state Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China department of geological science Ohio State University Columbus OH 43210 United States Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1934. are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

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On shifted convolution of half-integral weight cusp forms

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science China Mathematics 2010年第9期53卷 2411-2416页

作者： LUO WenZhi department of Mathematics,The ohio state university,231 West 18th Avenue,columbus,oh 432.0,USA 1. department of Mathematics The Ohio State University 231 West 18th Avenue Columbus OH 43210 USA

In this note,we present a simple approach for bounding the shifted convolution sum involving the Fourier coefficients of half-integral weight holomorphic cusp forms and Maass cusp forms.

关键词： shifted convolution half-integral weight cusp forms Poincar’e series Poisson-Voronoi summation formulas

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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 2. Institute of Resources & Environments, 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 200092, China Faculty of Earth science and state Key Laboratory of geological Processes and Mineral Resources China university of Geosciences Wuhan 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 13Ccarb and δ 13Ckerogen) from +0.4. (‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.38 (‰ V-PDB) to ?24.14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3 X 15%)) values from 0.015 to 0.14., TOC values from 0.02% to 0.21%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.20 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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Sorption behavior of U(VI), ^(234.U(VI) and ^(238)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

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science China Earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3, WANG Ju4. JIN Yuanxin4.& WANG Rucheng1 1. department of Earth sciences, state Key Laboratory of Mineral Deposit Research, Nanjing university, Nanjing 210093, China 2. Center of Materials Analysis, Nanjing university, Nanjing 210093, China 3. department of Environmental science and Engineering, Nanjing university, Nanjing 210093, China 4. Beijing Geology Institute, Nuclear Industry, Beijing 100029, China department of Earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis Nanjing university Nanjing China department of Environmental science and Engineering Nanjing university Nanjing China Beijing Geology Institute Nuclear Industry Beijing China

The first results of sorption experiments of U(VI), 234.(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234. onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

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Partial Collapsing Degeneration of Floer Trajectories and Adiabatic Gluing

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Acta Mathematica Sinica,English Series 2024年第1期40卷 161-249页

作者： Yong-Geun oh Ke ZHU Center for Geometry and Physics Institute for Basic Science(IBS)79 Jigok-ro 127beon-gilNam-guPohang-siGyeongsangbuk-doKorea 37673&POSTECHGyeongsangbuk doKorea department of Mathematics and Statistics Minnesota State UniversityMankatoMN 56001USA

In the present paper,we study partial collapsing degeneration of Hamiltonian-perturbed Floer trajectories for an adiabatic ε-family and its reversal adiabatic gluing,as the prototype of the partial collapsing degeneration of 2-dimensional(perturbed)J-holomorphic maps to 1-dimensional gradient *** consider the case when the Floer equations are S^(1)-invariant on parts of their domains whose adiabatic limit has positive length as ε→0,which we call thimble-flow-thimble *** main gluing theorem we prove also applies to the case with Lagrangian boundaries such as in the problem of recovering holomorphic disks out of pearly *** particular,our gluing theorem gives rise to a new direct proof of the chain isomorphism property between the Morse-Bott version of Lagrangian intersection Floer complex of L by Fukaya-oh-ohta-Ono and the pearly complex of L Lalonde and *** also provides another proof of the present authors’earlier proof of the isomorphism property of the PSS map without involving the target rescaling and the scale-dependent gluing.

关键词： Floer trajectory equation partial collapsing degeneration thimble-flow-thimble moduli space adiabatic gluing exponential decay estimates three-interval method

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A Feedback-Based Web Search Engine

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Wuhan university Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3 , XU Bao-wen 2,3,4., ZHOU Xiao-yu 2,3,4.1. department of Computer science and Engineering, Nanjing university of Posts and Telecommunications, Nanjing 210003, Jiangsu, China 2. department of Computer science and Engineering, Southeast university, Nanjing 210096, Jiangsu, China 3. Jiangsu Institute of Software Quality, Nanjing 210096 Jiangsu, China 4. The state Key Laboratory of Software Engineering, Wuhan university, Wuhan 4.0072, Hubei, China department of Computer science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4.Foundation item: Supported by the National Natural science Fundation of China (60373066). National Grand Fundamental Research 973 Program of China (2002CB31200). Opening Foundation of state Key Laboratory of Software Engineering in Wuhan university, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow universityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

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Ocean-Atmosphere Interaction in the Lifecycle of ENSO:The Coupled Wave Oscillator

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Chinese Annals of Mathematics,Series B 2009年第6期30卷 715-728页

作者： Jialin LIN Dedicated to Professor Andrew Majda on the Occasion of his 60th Birthday

To explain the oscillatory nature of E1 Nino/Southern Oscillation （ENSO）, many ENSO theories emphasize the free oceanic equatorial waves propagating/reflecting within the Pacific Ocean, or the discharge/recharge of Pacific-basin-averaged ocean heat content. ENSO signals in the Indian and Atlantic oceans are often considered as remote response to the Pacific SST anomaly through atmospheric teleconnections. This study investigates the ENSO life cycle near the equator using long-term observational datasets. Space-time spectral analysis is used to identify and isolate the dominant interannual oceanic and atmospheric wave modes associated with ENSO. Nino3 SST anomaly is utilized as the ENSO index, and lag-correlation/regression are used to construct the composite ENSO life cycle. The propagation, structure and feedback mechanisms of the dominant wave modes are studied in detail. The results show that the dominant oceanic equatorial wave modes associated with ENSO are not free waves, but are two ocean-atmosphere coupled waves including a coupled Kelvin wave and waves are not confined only to the Pacific a coupled equatorial Rossby （ER） wave. These Ocean, but are of planetary scale with zonal wavenumbers 1-2, and propagate all the way around the equator in more than three years, leading to the longer than 3-year period of ENSO. When passing the continents, they become uncoupled atmospheric waves. The coupled Kelvin wave has larger variance than the coupled ER wave, making the total signals dominated by eastward propagation. Surface zonal wind stress （x） acts to slow down the waves. The two coupled waves interact with each other through boundary reflection and superposition, and they also interact with an off-equatorial Rossby wave in north Pacific along 15N through boundary reflection and wind stress forcing. The precipitation anomalies of the two coupled waves meet in the eastern Pacific shortly after the SST maximum of ENSO and excite a dry atmospheric Kelvin wave which

关键词： ENSO Ocean-atmosphere interaction Equatorial waves

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Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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science China(Technological sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4.& CHEN Jiayi4.1. state Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101, China 2. Research Center for Remote Sensing and GIS, department of Geography, Beijing Normal {4., Beijing 100875, China 3. Graduate {4. of Chinese Academy of sciences, Beijing 100039, China 4. department of Atmospheric Physics, Peking {4., Beijing 100871, China 1. state Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, China in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South China

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science China Earth sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3, QIU Haiou4.& ZHAO Laishi3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 210008, China 2. Henan Institute of geological Survey, Zhengzhou 4.0007, China 3. state Key Laboratory of geological Processes and Mineral Resources at China {4. of Geosciences, Wuhan 4.0074. China 4. Faculty of Material sciences and Chemical Engineering, China {4. of Geosciences, Wuhan 4.0074. China 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan Institute of geological Survey Zhengzhou 450007 China 3. state Key Laboratory of geological Processes and Mineral Resources at China university of Geosciences Wuhan 430074 China 4. Faculty of Material sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South China, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13C background values are intensively controlled by palaeogeographic environment. In general, δ 13C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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science China Earth sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2, LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4.1. state Key Laboratory of Continental Dynamics, department of Geology, Northwest university, Xi`an 710069, China 2. state Key Laboratory of {4. Processes and Mineral Resources, China university of Geosciences, Wuhan 4.0074. China 3. Shenyang Institute of Geology and Mineral Resources, Shenyang 110032, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 51064., China 1. state Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. state Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 3. Shenyang Institute of Geology and Mineral Resources Shenyang 110032 China 4. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.31 wt%, Al_2O_3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12-20 μg/g) and high Sr (620-1323 μg/g) and Sr/Y(32-88), withhigh La_N/Yb_N ratio (10-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(14.)Nd/^(14.)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North China craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 120 to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North China Craton, delamination.

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