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Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1.2.*) Zhang Hongfu~2.Liu xiaoming~3.Li Zhitong~4 (1.School of {2. and Space {1.,Peking University,Beijing 1.0871.{2. 2.{3. of Geology and Geophysics and Key Laboratory of Mineral Resources,chinese academy of {1.,Beijing 1.002.,{2. 3.Key Laboratory of Continental Dynamics,Northwestern University,xi'an 71.069,{2. 4.{3. of Geology and Mineral Resources of Shenyang,Shenyang 1.003.1}{2.) [a]School of earth and Space {1. Peking University Beijing China [b]Laboratory of Mineral Resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]institute of Geology and Mineral Resources of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 1.6 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

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Early agricultural development and environmental effects in the Neolithic Longdong basin(eastern Gansu)

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chinese Science Bulletin 2011年第8期56卷 762-771页

作者： ZHOU xinYing LI xiaoqiang ZHAO KeLiang DODSON John SUN Nan YANG Qing State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Laboratory of Human Evolution and Archeological Science Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Graduate University of chinese academy of sciences Beifing 100049 China institute for {1.al Research the Australian Nuclear Science and Technology Organization Sydney NSW 1001 Australia

Neolithic agricultural development and environmental effects in the Longdong area were reconstructed using a synthetic approach,investigating pollen,charcoal,and seed remains for two cultural layer sections and five flotation *** show that Neolithic agriculture in the Longdong area had a simple organization and was dominated by the production of common millet,especially in the early and middle Yangshao *** the late Yangshao age,Neolithic agriculture developed into a more complex structure,dominated by both common and foxtail millet and the cultivation of rice and *** production of foxtail millet gradually increased through the Neolithic period,reaching its highest point during the Qijia *** were first cultivated during the late Yangshao culture,approximately 5000 cal a *** production began no later than 4800 cal a BP,and continued to exist in the Qijia culture,approximately 4000 cal a *** production in Neolithic Longdong,specifically in the "Yuan" area of the loess plateau,developed as a shrub and grass dominated *** in the river valleys was partly covered with Picea,Tusga,and Quercus coniferous and broadleaf mixed *** activity during the Neolithic period caused an increase in farmland on the loess tableland and a decrease in the abundance of shrub and grassland in the Longdong *** farmlands were abandoned,vegetation recovered with Hippophae-,Rosaceae-,Ephedra-,and Leguminosae-dominated shrublands and Artemisia-dominated grasslands.

关键词：新石器时代农业发展陇东地区环境影响甘肃东部早期新石器时期盆地

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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 {1. {2. 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,{1., Lanzhou 73.000,{2. 2.Department of Geology, Northwest University, xi’an 71.069,{2. 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{1.. 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 -1.4‰) are lighter than those in woody plant leaf ( from -1.5‰ to -1.2. ), 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 δ1.C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ1.C 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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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science china {1. {2. 2011年第4期54卷 493-508页

作者： xiAO Liang 1.2.3.4,SUN BaiNian 1.2.,LI xiangChuan 1.REN Wenxiu 1.&JIA Hui 1.1.Key Laboratory of Western china's {1.al Systems of the Ministry of Education and College of {2. and {1. Science,Lanzhou University,Lanzhou 73.000,china 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,{12. academy of sciences,Nanjing 2.0}008,china 3.College of Arts and sciences,Bryant University,Smithfield RI 02.1.,U.S.A. 4 Key Laboratory of Western china's Mineral Resources and Geological Engineering of Ministry of Education,Chang’an University,xi’an 71.054,china 1. Key Laboratory of Western china’s {1.al Systems of the Ministry of Education and College of {3. and {1. Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 1. leaf remains of *** from the Miocene xiannanshan Formation,Zhejiang Province(eastern china) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to {1.al *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to {1.al *** leaves can then be a better indicator of paleo{1.al ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleo{1.s using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleo{1.s based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene xiananshan Formation sun and shade leaves

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On three-dimensional geological modeling and visualization

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Science china {1. {2. 2004年第8期47卷 739-748页

作者： WU qiang1.& XU Hua2.1. Department of Resource Exploitation Engineering,{1. University of Mining and Technology, Beijing 1.0083.{1. 2. Beijing {3. of Petrochemical Technology, Beijing 1.2.1.,{1. 1. Department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. Beijing institute of Petrochemical Technology 102617 Beijing China

The technology of 3. geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3. geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3. geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3. dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3. geological modeling,geometrical model,system architecture,visualization

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Discovery of Early Triassic conodonts in western Gangdisê and the establishment of the Tangnale Formation

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Science china {1. {2. 2007年第12期50卷 1767-1772页

作者： ZHENG YouYe1. XU RongKe1.2. WANG ChengYuan3. MA GuoTao1. LAI XuLong1. YE DeJin2. CAO Liang1.& LIANG JiWei4 1.Faculty of earth Resourse,{1. University of Geoscience, Wuhan 43.074,{1. 2.Research {3. of Geological Survey of Gansu Province, Lanzhou 73.050,{1. 3.Nanjing {3. of Geology and Palaeontology,{12., Nanjing 2.0}008,{1. 4 Department of Geology, Northwest University, xi’an 71.069,{1. 1. Faculty of earth Resourse China University of Geoscience Wuhan 430074 China 2. Research institute of Geological Survey of Gansu Province Lanzhou 730050 China 3. Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 4. Department of Geology Northwest University Xi’an 710069 China

Most geologists believe that there are no Early and Middle Triassic strata in the W. Gandisê stratigraphic subregion, but the present authors have found Early Triassic conodonts for the first time in the Shiquanhe area, including five conodonts genera (Form genera): Pachycladina, Neohindeodella, Cornudina, Hadrodontina and Hibbardella sp. etc. Then we affirm that Early Triassic deposits exist in the Gandisê stratigraphic subregion, and establish the Tangnale Formation. The conclusion is new important complementary basal data for Triassic stratigraphy division of Gangdisê, reconstructing palaogeography and studying Gangdisê from Paleozoic to Mesozoic island-arc evolution and transi-tion.

关键词： Conodonts, Early Triassic, western Gangdisê

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Synthetically adaptive robust filtering for satellite orbit determination

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Science china {1. {2. 2004年第7期47卷 585-592页

作者： YANG Yuanxi1.& WEN Yuanlan2.1. xi’an Research {2. of Surveying and Mapping, xi抋’an 71.054,{1. 2. College of Aerospace and Material Engineering, National University of Defense Technology, Changsha 41.073.{1. 1. xi’an Research institute of Surveying and Mapping 710054 Xi’an China 2. College of Aerospace and Material Engineering National University of Defense Technology 410073 Changsha China

The quality of the satellite orbit determination is rested on the knowledge of per-turbing forces acting on the satellite and stochastic properties of the observations, and the ability of controlling various kinds of errors. After a brief discussion on the dynamic and geometric orbit determinations, Sage adaptive filtering and robust filtering are reviewed. A new synthetically adaptive robust filtering based on a combination of robust filtering and Sage filtering is *** is shown, by derivations and calculations, that the synthetically adaptive robust filtering for orbit determination is not only robust but also simple in calculation. It controls the effects of the outliers of tracking observations and the satellite dynamical disturbance on the parameter esti-mates of the satellite orbit.

关键词： satellite orbit, Sage filtering, adaptive orbit determination, robust estimation.

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Effects of different energy levels in low-protein diet on liver lipid metabolism in the late-phase laying hens through the gut-liver axis

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Journal of Animal Science and Biotechnology 2024年第5期15卷 2122-2136页

作者： Hong Hu Ying Huang Anjian Li Qianhui Mi Kunping Wang Liang Chen Zelong Zhao qiang Zhang xi Bai Hongbin Pan Yunnan Provincial Key Laboratory of Animal Nutrition and Feed Science Faculty of Animal Science and TechnologyYunnan Agricultural UniversityKunming 650201China College of Animal Science Anhui Science and Technology UniversityBengbu 233000China State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agriculture SciencesBeijing 100193China Shanghai BIOZERON Biotechnology Co. LtdShanghai 201800China WOD Poultry Research institute Beijing 100193China

Background The energy/protein imbalance in a low-protein diet induces lipid metabolism disorders in late-phase laying *** energy levels in the low-protein diet to adjust the energy-to-protein ratio may improve fat deposition,but this also decreases the laying performance of *** study investigated the mechanism by which different energy levels in the low-protein diet influences liver lipid metabolism in late-phase laying hens through the enterohepatic axis to guide feed optimization and nutrition strategies.A total of 2.8 laying hens were randomly allocated to the normal-energy and normal-protein diet group(positive control:CK)or 1.of 3.groups:lowenergy and low-protein diet(LL),normal-energy and low-protein diet(NL),and high-energy and low-protein diet(HL)*** energy-to-protein ratios of the CK,LL,NL,and HL diets were 0.67,0.74,0.77,and 0.80,*** Compared with the CK group,egg quality deteriorated with increasing energy intake in late-phase laying hens fed low-protein *** fed LL,NL,and HL diets had significantly higher triglyceride,total cholesterol,acetylCo A carboxylase,and fatty acid synthase levels,but significantly lower hepatic lipase levels compared with the CK *** transcriptome sequencing revealed that genes involved in fatty acid beta-oxidation(ACOX1.HADHA,EHHADH,and ACAA1.were downregulated,whereas genes related to fatty acid synthesis(SCD,FASN,and ACACA)were upregulated in LL group compared with the CK *** of the cecal microbiome showed that in hens fed an LL diet,Lactobacillus and Desulfovibrio were enriched,whereas riboflavin metabolism was *** metabolites that were most significantly affected by the LL diet included several vitamins,such as riboflavin(vitamin B2.,pantethine(vitamin B5 derivative),pyridoxine(vitamin B6),and 4-pyridoxic *** A lipid metabolism disorder due to deficiencies of vitamin B2.and pantethine originating from the metabolism of the cecal microb

关键词： Cecal microbiome Energy/protein imbalance Late-phase laying hens laying hens Liver lipid metabolism Low-protein diet Multi-omics

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Pb isotope geochemistry of lead, zinc, gold and silver deposit clustered region, Liaodong rift zone,northeastern china

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Science china {1. {2. 2005年第4期48卷 467-476页

作者： CHEN Jiangfeng1. YU Gang1. XUE Chunji2. QIAN Hui1. HE Jianfeng1. xiNG Zhi1.& ZHANG Xun1.1. School of earth and Space {1., University of Science and Technology of{2., Hefei 2.002.,{2. 2. Department of Geology, Chang’an University, xi’an 71.054,{2. 1. School of earth and Space {1. University of Science and Technology of China 230026 Hefei China 2. Department of Geology Chang’an University 710054 Xi’an China

Pb isotopic analyses were reported for sulfide and hydrothermal carbonate minerals and marble of the xiquegou lead-zinc, the Zhenzigou zinc-lead and the Gaojiapuzi silver deposits from the Qingchengzi ore field and the Beiwagou zinc-lead deposit in the west, Proterozoic Liaodong rift zone. Pb isotopic ratios of the marble from the Qingchengzi ore field range from 1..2. to 3..63.for 2.6 Pb/2.4Pb, 1..59 to 1..05 for2.7Pb/2.4Pb and 3..43.to 3..63.for 2.8Pb/2.4Pb. The marble gives a Pb-Pb isochron age of 1.2.±92.Ma, which is interpreted as the age of the metamorphism of the marble. Ore Pb, including Pb of sulfide and hydrothermal car- bonate minerals, from the Qingchengzi ore field shows limited variation with 2.6 Pb/2.4Pb=1..66- 1..96, 2.7 Pb/2.4Pb=1..60-1..74 and 2.8Pb/2.4Pb=3..94-3..60. In contrast, ore Pb from the Beiwagou deposit gives different Pb isotopic ratios with 2.6Pb/2.4Pb=1..68-1..81. 2.7 Pb/2.4Pb= 1..3.-1..45 and 2.8Pb/2.4Pb=3..3.-3..68. Pb of all deposits from the Liaodong rift zone is derived from the upper crust. Ore Pb of the Qingchengzi deposits is derived from a young upper crust. The model Th/U ratios of 4.40 to 4.74 for ore Pb are significantly different from that of 1.7 to 4.4 given by the marble of the Qingchengzi ore field, suggesting that marble is not the source of the ore Pb. Ore Pb of the Beiwagou deposit is extracted from its source and the deposit is formed at the Paleoproterozoic era. Different Pb isotopic ratios of the Qingchengzi ore field and the Beiwagou deposit are due to different ages of the deposits and suggest that the two types of deposits are derived from different sources and are possibly formed by different ore-forming processes.

关键词： Pb isotopes, source(s) of the ore-forming materials, origin of ore deposits, Liaodong rift zone.

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Sand control mechanism of radial well filled with phase change material in hydrate reservoir

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Petroleum Science 2024年第4期21卷 2571-2582页

作者： xiao-qiang Liu Zhong-xi Han Zhi-Lin Luo Hai-Long Lu Ying Sun Qing You Tian-Kui Guo Zhan-Qing Qu School of Energy Resources China University of Geosciences (Beijing) Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences (Beijing) china Research {1. of Petroleum Exploration and Development Engineering Technology Research institute of Southwest Oil & Gas Field Company PetroChina Beijing International Center for Gas Hydrate School of Earth and Space Sciences Peking University School of Advanced Material Peking University Shenzhen Graduate School School of Petroleum Engineering China University of Petroleum (East China)

Radial well filled with phase change material has been proposed as a novel sand control method for hydrate exploitation. In order to reveal the sand control mechanism, CFD-DEM coupling method is applied to simulate the migration, settlement, and blockage processes of sand particles in the radial *** obtained results indicate that three scenarios have been recognized for sand particles passing through sand control medium, based on the diameter ratio of sand control medium to sand particle（Dd）:fully passing（Dd= 8.75-2..5）, partially passing and partially blocked（Dd= 3.1.-5.63., and completely blocked（Dd= 2.1.-3.2.0}. After being captured by the sand control medium, sand particles can block pores, which increases fluid flow resistance and causes a certain pressure difference in the radial *** pressure in the radial well should be lower than the hydrate phase equilibrium pressure during sand control design, for the purpose of promoting hydrate decomposition, and sand capture. The length of the radial well should be optimized based on the reservoir pore pressure, production pressure difference,bottom hole pressure, and the pressure gradient in the radial well. It should be noticed that the sand control medium leads to a decrease in permeability after sand particles captured. Even the permeability is reduced to several hundred millidarcy, it is still sufficient to ensure the effective flow of gas and water after hydrate decomposition. Increasing fluid velocity reduces the blocking capacity of the sand control medium, mainly because of deterioration in bridging between sand particles.

关键词： Hydrate reservoir Sand control Radial well CFD-DEM

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