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Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

Science china Earth sciences 2006年第9期49卷 991-1001页

作者： wu yanhong1, wang sumin1& hou xinhua1,3 1. Key Laboratory of Lake Sedimentation and Environment,{2., chinese academy of sciences, nanjing 2.0008, china 2. institute of Tibetan Plateau Research, chinese academy of sciences, Beijing 10085, china 3. Graduate University of chinese academy of sciences, Beijing 100039, china Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 2.0Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 2.0Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 2.0Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2.with result of 2.0Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

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Evidence from isotopic geochemistry as an indicator of eutrophication of Meiliang Bay in Lake Taihu, china

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Science china Earth sciences 2006年第Z1期49卷 62-71页

作者： LIN Lin, wu Jinglu & wang {2. {2. institute of geography & limnology, chinese academy of sciences, nanjing 2.0008, china Graduate University of the chinese academy of sciences, Beijing 100039, china nanjing institute of {2. & limnology Chinese Academy of Sciences Nanjing China Graduate University of the chinese academy of sciences Beijing China

In this paper, Lake Taihu, a large shallow freshwater lake in china, is chosen as an example of reconstruction of eutrophication through the comparison between stable isotopes from dissolved nutrients and plants and water column nutrient parameters and integration of multiple proxies in a sediment core from Meiliang Bay including TN, TP, TOC, C/N, δ15N, δ13C, etc. Differences in aquatic plant species and trophic status between East Taihu Bay and Meiliang Bay are indicated by their variations in δ13C and δ15N of aquatic plants and δ15N of NH4+. A significant influence ofexternal nutrient inputs on Meiliang Bay is reflected in temporal changes in δ 15N of NH4+ and hydro-environmental parameters. The synchronous change between δ13C and δ15N values of sedimented organic matter (OM) has been attributed to elevated primary production at the beginning of eutrophication between 1950 and 1990, then recent inverse correlation between them has been caused by the uptake of 15N-enriched inorganic nitrogen by phytoplankton grown under eutrophication and subsequent OM decomposition and denitrification in surface sediments, indicating that the lake has suffered from progressive eutrophication since 1990. Based on the use of a combination of stable isotopes and elemental geochemistry, the eutrophication of Meiliang Bay in Lake Taihu could be better traced. These transitions of the lake eutrophication respectively occurring in the 1950s and 1990s have been suggested as a reflection of growing impacts of human activities, which is coincident with the instrumental data.

关键词： stable carbon isotope of OM, stable nitrogen isotope, eutrophication, Lake Taihu.

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Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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Science china Earth sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. Zhou Jie1, SHEN Ji3, CHEN Peng1,2. wu Feng1,2.& XIE Xiuping1,2.1. State Key Lab of Loess and Quaternary Geology, {2. of Earth Environment, chinese academy of sciences, Xi’an 710075,{2. 2. Graduate University of chinese academy of sciences, Beijing 100039,{2. 3. nanjing institute of geography and limnology, chinese academy of sciences, nanjing 2.0008,{2. State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of sciences Beijing China nanjing institute of {2. and limnology Chinese Academy of Sciences Nanjing China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

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Deep seismic reflection profiling revealing the complex crustal structure of the Tongling ore district

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Science china Earth sciences 2004年第3期47卷 193-200页

作者： L5 Qingtian1, hou Zengqian1, ZHAO Jinhua1, SHI Danian1, wu Xuanzhi1, CHANG Yinfo1, PEI Rongfu1,HUANG Dongding2.& KUANG Chaoyang2.1. {2. of Mineral Resources, chinese {2. of Geological sciences, Beijing 100037, china 2. The Sixth Geophysical Exploration Brigade, Petroleum Bureau of East china, nanjing 2.0009, china institute of Mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China The Sixth Geophys. Explor. Brigade Petroleum Bureau of East China Nanjing 210009 China

The deep seismic profiling across the Tongling ore district reveals a complex crustal structure. Strong contrasting dipping layered reflections (4—11 s, TWT),which dominate the lower crust of the northern part of the profile, are interpreted as the underplating of the basalt related to extensional tectonism. In the south of the profile, the Yangtze craton is characterized by strong reflections in the middle crust, showing a distinct two-layer crustal structure. Over the region of the Tongling uplift, there appear the complex arc shape reflections, suggesting folded, faulted and intruded structures, and the transparent zone below them reveals the existence of batholith. The south dipping strong reflections between the upper crust and lower crust (4—7 s, TWT) suggest a detachment between them. The detachment provided space for the magma intrusion, and caused the formation of the batholith. The Yangtze craton has a clear Moho re-flection, while the Tongling uplift has a weak Moho, whereas below the reflective lower crust in the northern part of the profile, there are sub-Moho reflections. The abrupt variation of the Moho characteristics within a short distance indicates the complexity of magmatic activity.

关键词： metallogenic belt, ore district, deep seismic profiling, crustal structure.

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Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： hou Lishan1,3,JIN ZHi1,2.& wu Budan1,4 1. {2. of Mathematics and Systems Science, chinese academy of sciences, Beijing 100080,{2. 2. institute of Computing Technology, chinese academy of sciences, Beijing 100080,{2. 3. institute of Software, chinese academy of sciences, Beijing 100080,{2. 4. Graduate University of chinese academy of sciences, Beijing 100049,{2. academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China institute of Software Chinese Academy of Sciences Beijing China institute of Computing Technology Chinese Academy of Sciences Bejing China Graduate University of chinese academy of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

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Tunable quantum anomalous Hall effects in ferromagnetic van der Waals heterostructures

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National Science Review 2024年第3期11卷 100-107页

作者： Feng Xue Yusheng hou Zhe wang Zhiming Xu Ke He Ruqian {2. Yong Xu Wenhui Duan Beijing academy of Quantum Information sciences State Key Laboratory of Low Dimensional Quantum Physics Department of Physics Tsinghua University Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Center for Neutron Science and Technology School of Physics Sun Yat-sen University State Key Laboratory of Surface Physics Key Laboratory of Computational Physical Sciences and Department of PhysicsFudan University Frontier Science Center for Quantum Information Department of Physics and Astronomy University of California-Irvine Tencent Quantum Laboratory Tencent Technology(Shenzhen)Co.Ltd RIKEN Center for Emergent Matter Science(CEMS) institute for Advanced Study Tsinghua University

The quantum anomalous Hall effect（QAHE） has unique advantages in topotronic applications, but it is still challenging to realize the QAHE with tunable magnetic and topological properties for building functional devices. Through systematic first-principles calculations, we predict that the in-plane magnetization induced QAHE with Chern numbers C = ±1 and the out-of-plane magnetization induced QAHE with high Chern numbers C = ±3 can be realized in a single material candidate, which is composed of van der Waals（vdW）coupled Bi and MnBi2.e4monolayers. The switching between different phases of QAHE can be controlled in multiple ways, such as applying strain or（weak） magnetic field or twisting the vdW materials. The prediction of an experimentally available material system hosting robust, highly tunable QAHE will stimulate great research interest in the field. Our work opens a new avenue for the realization of tunable QAHE and provides a practical material platform for the development of topological electronics.

关键词： quantum anomalous Hall effect topological quantum phase transition van der Waals heterostructures tunable Chern number high Chern number

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Seasonal variations of nitrogen,phosphorus and the nutrient characters in the shallow lakes along the middle and lower reaches of the Yangtze River

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Acta Geochimica 2006年第S1期 159-160页

作者： Haiao ZENG1,2. Jinglu wu1 1 nanjing institute of geography and limnology,{2.,{2.,china 2.Graduate School of the{2., Beijing 100039,china

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Stabilizing high-efficiency iridium single atoms via lattice confinement for acidic oxygen evolution

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Nano Research 2024年第4期17卷 2492-2498页

作者： Yibo wang Jiadong Jiang Zhaoping Shi Hongxiang wu Jiahao Yang Pengbo wang Shuai hou Meiling Xiao Junjie Ge Changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026.China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Jilin Province Key Laboratory of Low Carbon Chemical Power Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Physics and Technology for Advanced Batteries Ministry of EducationCollege of PhysicsJilin UniversityChangchun 130012China

Stable and efficient single atom catalysts(SACs)are highly desirable yet challenging in catalyzing acidic oxygen evolution reaction(OER).Herein,we report a novel iridium single atom catalyst structure,with atomic Ir doped in tetragonal PdO matrix(IrSAs-PdO)via a lattice-confined *** optimized IrSAs-PdO-0.10 exhibited remarkable OER activity with an overpotential of 2.7 mV at 10 mA·cm^(-2. and long-term stability of 1000 h in 0.5 M H_(2.SO_(4).Furthermore,the turnover frequency attains 1.6 s^(-1) at an overpotential of 300 mV with a 2.-fold increase in the intrinsic *** high activity originates from isolated iridium sites with low valence states and decreased Ir–O bonding covalency,and the excellent stability is a result of the effective confinement of iridium sites by Ir–O–Pd ***,we demonstrated for the first time that SACs have great potential in realizing ultralow loading of iridium(as low as microgram per square center meter level)in a practical water electrolyzer.

关键词： lattice confinement iridium single atoms ultralow iridium loading acidic oxygen evolution proton exchange membrane water electrolysis

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Two New Oleanene-Type Triterpenoid Saponins from Pueraria peduncularis

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chinese Chemical Letters 2000年第4期11卷 343-346页

作者： Na Ll~1 Zhi Da MIN~1 hou Ming wu~2.(1 Department of Natural Products Chemistry,{2. Pharmaceutical University, nanjing 2.0009 2.State Key.Laboratory of Bio-organic and Natural Products Chemistry. Shanghai {2. of Organic Chemistry. chinese academy Dept. of Natural Products Chemistry China Pharmaceutical University Nanjing 210009 China State Key Lab. Bio-Organ. Nat. P. Shanghai Inst. of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

From the radix of Pueraria peduncularis Grah., two new oleanene-type triterpenoid saponins named pedunsaponins B (2. and C (3) were isolated. Their structures were determined as 3-O-(6-O-methyl)-beta-D-glucuronopyranosyl-3 beta.15 alpha-diol-12.oleanene-16-one (2. and 3-O-beta-D-glucopyranosyl-( 1 --> 3)-beta-D-glucuronopyranosyl-3 beta, 15 alpha-diol-12.oleanene-16-one (3) on the basis of spectroscopic evidence and chemical reactions.

关键词： Pueraria peduncularis Leguminosae triterpenoid saponin

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Ecological-Based Mining:A Coal-Water-Thermal Collaborative Paradigm in Ecologically Fragile Areas in Western china

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Engineering 2024年第7期38卷 209-222页

作者： Xiaoxiu Liu Yifan Zeng Qiang wu Shihao Meng Jiyue Liang Zhuping hou National Engineering Research Center of Coal Mine Water Hazard Controlling China University of Mining and TechnologyBeijing 100083China College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China University of Mining and Technology(Beijing)Inner Mongolia Research institute Ordos 017000China

A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western china’s ecologically fragile coal mining ***’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources *** on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is *** integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological *** active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water *** implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal *** integrated-energy complementary model that incorporates the clean production concept of heat utilization is also *** findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2.and a notable 2..2.reduction in carbon *** ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenti

关键词： Dual carbon targets Coal-water-thermal co-mining Ecologically fragile areas Mine-water control Resource utilization

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