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Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science China earth sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2.& WU Baoxiang1 1 Key Laboratory of Petroleum Resources Research, institute of Geology and Geophysics, Chinese {3. of {2., Lanzhou 73.000, China 2.Department of Geology, Northwest University, xi’an 710069, China 1. Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in China. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -2.4‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142. ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13. and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13. values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

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Megaripples from the Mesoproterozoic of the Kimberley region,northwestern Australia and its geological implications

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Journal of Palaeogeography 2012年第1期1卷 15-25页

作者： Lan Zhongwu 1,2.3.,Zhong-Qiang Chen 2.4,1.State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,Chinese {3. of {2.,Beijing 10002.,China 2.School of {3. and environment,The University of Western Australia,Australia 3.Key Lab of Petroleum Resources Research,institute of Geology and Geophysics,Chinese {3. of {2.,Beijing 10002.,China 4.State Key Laboratory of Biogeology and environmental Geology,China University of Geo{2. (Wuhan),Wuhan 43.074,China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of earth and environment The University of Western Australia Key Lab of Petroleum Resources Research Institute of Geology and Geoph

Large ripples are described from the Mesoproterozoic Hilfordy Formation in the Kimberley region,northwestern *** ripple index (RI) and ripple symmetry index (RSI) suggest the Kimberley ripples were likely generated by storm *** wave height is up to 15 2. cm and wave length is up to 70 90 *** features,incorporated with other morphological characteristics such as symmetry,steepness,ripple spacing,and compositions,agree well with the megaripples previously reported from the intertidal-nearshore settings of modern seas and the geological *** Mesoproterozoic ripples were likely generated by the storm-induced *** survey of the global record of megaripples reveals that such structures have occurred through the geological past from the Archean to present *** were particularly common in the Neoproterozoic and had the largest ripple length and ripple height among the modern and geological *** is probably because extreme storms prevailed at that *** frequent occurrence in present day beach is probably due to the prevalence of extreme storms caused by the monsoon or tsunami/earthquake influenced climatic regimes.

关键词： megaripples palaeohydrodynamics extreme storms Mesoproterozoic Hilfordy Formation Kimberley northwestern Australia

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CARBONATITES FROM THE EASTERN HIMALAYAN SYNTAxiS: PETROLOGY AND TECTONIC IMPLICATIONS

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地学前缘 2000年第S1期7卷 10-11页

作者： Liu Yan 1, Zhong Dalai 2. Ji Jianqing 3.1 institute of Geology, Chinese academy of Geological {2., Beijing 10003., China 2.institute of Geology & Geophysics, Chinese academy of {2., Beijing 10002., China 3.Department of Geology, Pek

Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been discovered to occur in the orogenic belts in recent years, most of these rocks are related to post\|orogenic magmatism, that is, the rocks occur in the specially extensional setting. Therefore it is unusual that such magmatic rocks occur in the typical convergent environment. Here we report carbonatites and associated ultramafic and mafic rocks in the core of the eastern Himalayan syntaxis. The eastern Himalayan syntaxis consists of three tectonic units: the Gangdise, the Yarlung Zangbo, and the Himalayan units, each of which is bounded by faults (Liu & Zhong, 1997). The Himalayan unit, the northernmost exposed part of the Indian plate, is divided into two complexes, the amphibolite facies complex in the south and the granulite facies complex in the north. The granulite facies complex in the Himalayan unit have been argued to experience high\|pressure metamorphism and represent materials buried to upper\|mantle depths (Liu & Zhong, 1997). The carbonatites and associated ultramafic and mafic rocks only occur in the granulite facies rocks and are divided into two belts: northern and southern *** northern belt extends at least 3.km, and is about {3.km in width. The southern belt extends several kilometers, and is 3.m or so in width. Each belt consists mainly of differently compositional dykes, extending parallel to gneissosity of granulite facies gneiss. Carbonatitic agglomerates are observed in the northern belt. From the center of carbonatite dykes to country rocks, five types of rock are observed: the center parts of carbonatites, the rim parts of carbonatites, ultramafic and mafic rocks, altered rocks and country rocks. The gneissosity of country rock was deformed by intrusion of dykes.

关键词： Eastern Himalayan Syntaxis carbonatites ultramafic rocks carbonatitie magmatism convergent environment

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Helium isotope investigation on magnetic reversal boundaries of loess-paleosol sequence at Luochuan, central Chinese Loess Plateau

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Chinese Science Bulletin 2007年第17期52卷 2407-2412页

作者： DU XueQing1,6, WANG YongHong2. REN JianGuo3. YE xianRen4 & LU HuaYu5,1 1 State Key Laboratory of Loess and Quaternary Geology, institute of {3. {2., Chinese {3. of sciences, xi’an 710075, China 2.College of Marine Geosciences, Ocean University of China, Qingdao 2.6003. China 3.National Natural Science Foundation of China, Beijing 100085, China 4 Lanzhou Research Center for Petroleum and Natural Gas Resources, institute of Geology and Geophysics, Chinese {3. of sciences, Lanzhou 73.000, China 5 Key Laboratory of Coast and Island Development, School of Geographic and Oceanographic sciences, Nanjing University, Nanjing 2.0093. China 6 Graduate University of Chinese {3. of sciences, Beijing 100049, China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China

Extraterrestrial particles have higher 3.e/4He ratios than those of terrestrial sediments ( > 100 Ra versus < 0.03.Ra, where Ra is the 3.e/4He ratio normalized to the atmospheric value of 1.4×10?6). The inter- planet... 详细信息

Extraterrestrial particles have higher 3.e/4He ratios than those of terrestrial sediments ( > 100 Ra versus 3.Ra, where Ra is the 3.e/4He ratio normalized to the atmospheric value of 1.4×10?6). The inter- planetary dust particles (IDPs), which are very rich in 3.e, continuously bombard the earth and can accumulate in deposits. IDPs sedimentation rate changes can significantly influence 3.e concentration in the earth surface sediments. Since IDPs are not easy to detect in terrestrial deposits, measuring helium isotopes is a helpful approach to examine changes in IDPs. Helium concentration and helium isotopic composition magnetic substances and the quartz particles were examined for helium concen- tration and helium isotopic ratio. Results show that the 3.e/4He ratio and the 3.e concentrations of the magnetic substances are clearly higher than those of the bulk samples and the quartz particles, and, the 3.e/4He ratio of the extracted magnetic substances is also higher than that of the average level of the earth’s crust. The higher helium content in the magnetic fractions can be explained by an influx of IDPs.

关键词：中国黄土高原古土壤氦同位素行星际尘埃颗粒反方向磁化

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Effect of Cobalt-Doped Framework on Formation of Todorokite from Layered Manganese Oxides with Mg^(2.)/Co^(2.) Ions as Template

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Pedosphere 2011年第6期21卷 730-737页

作者： CUI Hao-Jie LIU Fan TAN Wen-Feng FENG xiong-Han institute of Urban environment Chinese Academy of Sciences Xiamen 361021 （China） Key Laboratory of Subtropical Agricultural Resources and environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 （China）

Cobalt （Co） exists in significant quantities in naturally occurring manganese （Mn） oxides and alters the growth of Mn oxide crystals. Four-layered Mn oxides, Na-buserite （Na-bus） and three Co-doped Na-buserite samples prepared from oxidation of Mn（OH）2.with 5%, 10%, and 2.% Co/（Mn ＋ Co） molar ratios （5Co-Na-bus, 10Co-Na-bus, and 2.Co-Na-bus）, were used to prepare todorokite, a common Mn oxide on the earth＇s surface, using Mg2./Co2. ions as a template. The results showed that todorokites could be obtained by reflux treatment of Mg2.-exchanged non-doped Na-buserite and three Co-doped Na-buserites at atmospheric pressure. However, the formation of todorokites was prohibited by reflux treatment of Co2.-exchanged Na-bus, 5Co-Na-bus, and 10Co-Na-bus samples. Instead, todorokite was obtained by the reflux treatment of Co2.-exchanged 2.Co-Na-bus samples under atmospheric pressure. X-ray photoelectron spectroscopy analysis showed that doped Co existed as Co3. in the MnOs layers of doped Na-buserites. The amount of substituted Co3. in the MnO6 layers may play a key role in the conversion of buserite to todorokite using Co2. ions as a template.

关键词： Mn oxide Na-buserite reflux treatment transformation tunnel structure

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Solar energetic particles intensity variations associated with a tilted-dipole 3. corotating interaction region

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earth and Planetary Physics 2024年第5期8卷 797-810页

作者： YuJi Zhu Fang Shen xi Luo Yang Wang BoFeng Tang State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Shandong institute of Advanced Technology (SDIAT) College of earth and Planetary sciences University of Chinese Academy of Sciences School of Science Harbin Institute of Technology

The effect of a tilted-dipole three-dimensional corotating interaction region(CIR) on the transport and acceleration of solar energetic particles(SEPs) is *** this work,we discussed how the particle intensity longitudinal and radial dependence might be influenced by the background ***,we investigate how the spectral index distribution is modulated by the CIR structure We use the focused transport equation(FTE) to describe the propagation and acceleration of SEPs in a tilt-dipole 3. CIR,generated by the high-resolution 3. magnetohydrodynamic(MHD) *** forward stochastic differential method is used to solve the *** protons with theE～(-4.4)spectrum from 0.5 to 15 MeV are injected uniformly at the heliographic equator of 0.15 *** quantities are extracted along each interplanetary magnetic field(IMF) line to show the *** the tilted-dipole CIR background,if injected from the solar equator at the inner boundary,particles in the slow flow are transported to higher latitudes due to the extension of the IMF lines to higher *** longitudinal patterns of the particles are dominated by the density of IMF *** focusing effect modulates the longitudinal variation of the particle intensity and gives rise to new longitudinal intensity *** adiabatic effect largely increases the intensity fluctuation along the *** structure of the solar wind can also lead to the difference of the index α in the empirical functionI＿(max)=kR～(-α),describing the radial variation of peak intensity according to our *** the influence of the CIR structure,the index α varies from 1.9 to 3.4 at 0.3.1.0 *** variation of the solar wind speed should be considered when estimating the radial dependence of the SEP peak *** spectra indices rise near the CIR boundaries and drop near the stream interface(SI).The adiabatic effect makes the spatial variability of the spectral index *** spectral index could be sim

关键词： solar energetic particle (SEP) corotating interaction regions (CIR) magnetohydrodynamic (MHD)

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The application of hyperspectral remote sensing to coast environment investigation

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Acta Oceanologica Sinica 2009年第2期28卷 1-13页

作者： ZHANG Liang ZHANG Bin CHEN Zhengchao ZHENG Lanfen TONG Qingxi State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Science Beijing 100101 China Naval institute of Hydrographic Surveying and Charting Tianjin 300061 China Center for earth Observation and Digital earth Chinese Academy of Science Beijing 100190 China

Requirements for monitoring the coastal zone environment are first summarized. Then the appli- cation of hyperspectral remote sensing to coast environment investigation is introduced, such as the classification of coast beaches and bottom matter, target recognition, mine detection, oil spill identification and ocean color remote sensing. Finally, what is needed to follow on in application of hyperspectral remote sensing to coast environment is recommended.

关键词： hyperspectral remote sensing coastal zone ocean color remote sensing

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Suppressed Internal Intrinsic Stress Engineering in High-Performance Ni-Rich Cathode Via Multi layered In Situ Coating Structure

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Energy & environmental Materials 2024年第2期7卷 58-66页

作者： Jiachao Yang Yunjiao Li xiaoming xi Junchao Zheng Jian Yu Zhenjiang He School of Metallurgy and environment Central South UniversityChangsha 410083China Engineering Research Center of the Ministry of Education for Advanced Battery Materials Central South UniversityChangsha 410083China Changsha Research institute of Mining and Metallurgy Changsha 410083China Ningbo Ronbay New Energy Technol Co Ltd Tanjialing East Rd 39Ningbo 315400China

LiNi_(x)Co_(y)Al_(z)O_(2.(NCA)cathode materials are drawing widespread attention,but the huge gap between the ideal and present cyclic stability still hinders their further commercial application,especially for the Ni-rich LiNi_(x)Co_(y)Al_(z)O_(2.(x>0.8,x+y+z=1)cathode material,which is owing to the structural degradation and particles'intrinsic *** tackle the problems,Li_(0.5)La_(2.Al_(0.5)O_(4)in situ coated and Mn compensating doped multilayer LiNi_(0.82.Co_(0.14)Al_(0.04)O_(2.was *** refinement indicates that La-Mn co-modifying could realize appropriate Li/Ni disorder *** results and in situ XRD patterns reveal that the LLAO coating layer could effectively restrain crack in secondary particles benefited from the suppressed internal *** further improves as NCA-LM2.has superior mechanical *** SEM,TEM,XPS tests indicate that the cycled cathode with LLAO-Mn modification displays a more complete morphology and less side reaction with *** was used to further investigate cathode-electrolyte interface which was reflected by gas ***-LM2.releases less CO_(2.than NCA-P indexing on a more stable *** modified material presents outstanding capacity retention of 96.2.after 100 cycles in the voltage range of 3.0-4.4 V at 1C,13.higher than that of the pristine and 80.8%at 1 C after 3.0 *** excellent electrochemical performance could be attributed to the fact that the high chemically stable coating layer of Li_(0.5)La_(2.Al_(0.5)O_(4)(LLAO)could enhance the interface and the Mn doping layer could suppress the influence of the lattice mismatch and *** believe that it can be a useful strategy for the modification of Ni-rich cathode material and other advanced functional material.

关键词： compensating doped in situ coating multilayer material Ni-rich cathode materials suppressed internal strain

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Geochemical Characteristics and Development Significances of Constant and Trace Elements from Coalbed Methane Co-Produced Water:A Case Study of the Shizhuangnan Block,the Southern Qinshui Basin

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Journal of earth Science 2024年第1期35卷 51-61页

作者： Yang Li Shuheng Tang Jian Chen Songhang Zhang Zhaodong xi Key Laboratory of Universities in Anhui Province for Prevention of Mine Geological Disasters Anhui University of Science and TechnologyHuainan 232001China School of earth and environment Anhui University of Science and TechnologyHuainan 232001China National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing 102249China School of Energy Resource China University of GeosciencesBeijing 100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas Ministry of Land and ResourcesBeijing 100083China

As an unconventional natural gas resource,coalbed methane(CBM)development releases a large amount of CBM wells co-produced *** characteristics of the co-produced water provide an essential foundation for the production dynamics of CBM reservoirs if the impacts of fracturing fluids and other aquifers can be *** the Shizhuangnan Block of the southern Qinshui Basin,constant and trace elements in CBM co-produced water from the wellheads were collected and determined,which is applied to assess water source,fracturing fluid effect,and CBM *** on principle component analysis and hierarchical clustering analysis,the water samples are divided into four *** suggests that different characteristics affected by water-rock interaction,reservoir environment,aquifer recharge,and hydraulic fracturing result in the various ratios of Na^(+)/Cl^(-),alkalinity(HCO_(3.^(-)+CO_(3.^(2.))/Cl^(-)and other specific ***,Cl^(-)is selected as a dividing line for complete fracturing fluid flow back,associated with organic-bound chlorine complexes in the original coal seam *** to constant elements,there is a significant correlation between Li and Sr concentrations and CBM productivity,so templates regarding trace elements can be used to distinguish various sources of the co-produced water.

关键词： coalbad methane CBM co-produced water hydraulic fracturing Qinshui Basin

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Effect of Incoming Vortex on Secondary Flows in Turbine Cascades with Planar and Non-Axisymmetric Endwall

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Journal of Thermal Science 2024年第1期33卷 138-157页

作者： CAO Zhiyuan WANG Chuxuan SONG Zhigao GAO xi ZHAO Wei LIU Bo School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China National Key Laboratory of Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi'an 710072China institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100080China

Non-Axisymmetric Endwall Profiling(NAEP) is commonly utilized in turbines to eliminate secondary ***,most of the NAEP methods consider a single-blade row environment without incorporating the effect of the stage *** paper aims to investigate the influence mechanism of the incoming vortex on the endwall secondary flow structures of NAEP in a highly loaded turbine *** model the incoming vortex in a stage environment,this study considers a half-delta wing as the vortex generator at the upstream of the turbine *** NAEP is then carried out for a highly loaded turbine cascade with an in-house numerical optimization design platform subject to no incoming *** simulation is also carried out under the influence of the incoming vortex for the turbine cascades with both planar and non-axisymmetric *** paper furthers investigated the pitchwise effect of the incoming vortex on the near endwall secondary *** results indicate that the NAEP effectively improves the endwall secondary flow of the turbine cascade,where the total pressure loss coefficient and the secondary kinetic energy(SKE) are reduced by 7.3.,and 45.7%,*** is further seen that with the incoming vortex,the NAEP achieves a considerable control effect on the endwall secondary flow of the turbine *** incoming vortex,the NAEP can still achieve considerable control effect on the endwall secondary flow of the turbine cascade;the averaged reductions of loss coefficient and SKE are 7.8% and 14.2.,*** some pitchwise locations,incoming vortex can suppress the convection of cross-passage flow toward the suction corner greatly and reduce the loss coefficient of the baseline *** incoming vortex at 4/7 pitch impinged right at the blade leading edge,leading to the generation of low-momentum fluid,which increased the size and the strength of the horseshoe *** all the pitchwise locations,NAEP can suppress the seco

关键词： non-axisymmetric endwall secondary flow incoming vortex passage vortex stage environment

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