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Amelioration of habitat since the early Holocene contributed to the origin of agriculture in the farming-pastoral zone of northern China

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Science China Earth Sciences 2024年第8期67卷 2535-2546页

作者： Xin JIA Zhiping ZHANG Yonggang SUN Runqi JIANG Shuangwen YI Wei CHEN Jue SUN Guoqiang LI Shuzhi WANG Enrui LI Xiaonong HU Qingchun BAO Harry F.LEE Huayu LU Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Schlool of History and Culture Chifeng UniversityChifeng 024000China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Institute of Archaeology Chinese Academy of Social SciencesBeijing 100710China Ulanqab Museum Ulanqab 012000China The Institute of Cultural Relics and Archaeology Hohhot 010011China Department of Geography and Resource Management The Chinese University of Hong KongHong Kong 999077China Key Laboratory of Virtual Geographic Environment(Ministry of Education of prc) Nanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Institute of Environmental Archaeology Nanjing Normal UniversityNanjing 210023China

The origin of agriculture in the farming-pastoral zone of northern China remains in *** central region of the Inner Mongolia Plateau is located in the core area of the farming-pastoral zone;thus,it is a critical region for exploring the origin of the dryland farming system in northern *** study selected the Yumin Site and Banan Site,which belong to the Yumin Culture-the beginning of Neolithic culture in Inner Mongolia-as the research *** on the quartz optically stimulated luminescence(OSL)dating on the sedimentary sections from the Yumin site(YM)and Banan site(BN1 and BN2),the Holocene chronology framework of each section was *** that,by identifying carbonized grains in the Yumin site and the multi-proxy analysis of each section,we investigated the relationship between the origin of agriculture and climate change in this *** results revealed that the timing of the origin of agriculture recorded in the Yumin site lagged behind the timing of a significant increase of precipitation during the early Holocene but coincided with the timing of a significant increase of vegetation around 8.4 *** phenomenon was further confirmed by the published high-resolution paleoenvironmental records from the surrounding area of the Yumin *** propose that with the gradual amelioration of hydrothermal conditions since the beginning of the Holocene,the regional ecosystem had been improved,resulting in the gradual conversion of the land surface from infertile sand to organic-rich soil,providing an appropriate environmental foundation for the origin of dryland farming in northern China around 8.4 *** study highlighted that the“accumulative environmental effects”during the early Holocene played a vital role in the origin of agriculture in northern China and provided a reference for agricultural management in the context of future climate change.

关键词： Origin of agriculture Accumulative environmental effects Yumin Culture Northern China Holocene

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Engineering of geometrical configurations in dual-atom catalysts for electrocatalytic applications

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Journal of Energy Chemistry 2024年第7期94卷 273-287页

作者： Tao Zhang Yifan Liu Liang Xue Jingwen Sun Pan Xiong Junwu Zhu Key Laboratory for Soft Chemistry and Functional Materials of Ministry Education School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094JiangsuChina

Geometrical configurations play a crucial role in dual-atom catalysts(DACs)for electrocatalytic *** progress has been made to design DACs electrocatalysts with various geometri-cal configurations,but in-depth understanding the relationship between geometrical configurations and metal-metal interaction mechanisms for designing targeted DACs is still *** this review,the recent progress in engineering of geometrical configurations of DACs is systematically *** on the polarity of geometrical configuration,DACs can be classified into two different types that are homonuclear and heteronuclear ***,with regard to the geometrical configurations of the active sites,homonuclear DACs are identified into adjacent and bridged configurations,and heteronuclear DACs can be classified into adjacent,bridged,and separated ***,metal-metal interactions in DACs with different geometrical configurations are ***,the applications of DACs in different electrocatalytic reactions are discussed,including the oxygen reduction reaction(ORR),oxygen evolution reaction(OER),hydrogen evolution reaction(HER),and other ***,the future challenges and perspectives for advancements in DACs are *** review aims to provide inspiration for the design of highly effcient DACs towards energy relatedapplications.

关键词： Dual-atom catalysts Geometrical configurations Homonuclear Heteronuclear Electrocatalysis

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Fluid-structure interaction simulation of dynamic response and wake of floating offshore wind turbine considering tower shadow effect

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Acta Mechanica Sinica 2024年第8期40卷 67-84页

作者： Songyang Liu Zhiqiang Xin Lei Wang Zhiming Cai College of Mechanics and Engineering Science HoHai UniversityNanjing211100China

The comprehensive numerical simulation of the tower shadow effect on floating offshore wind turbines(FOWTs),an area less explored compared to fixed-bottom wind turbines,is presented in this *** atmospheric boundary layer inflow and the joint north sea wave project random wave are used as the operating conditions for *** combination of computational fluid dynamics(CFD)software simulator for wind farm applications and turbine simulation tool OpenFAST is used to implement fluid-structure interaction *** output power,platform motion,wake velocity deficit and vortex structures are analyzed to reveal the influence of the tower shadow effect on the *** results indicate that due to the fluctuation caused by the turbulent wind and the floating platform motion,the tower shadow effect of FOWT is less significant for its periodic power decay than that of fixed-bottom wind *** according to the velocity deficit analysis,the influence area of the tower shadow effect on the wake is mainly in the near wake region.

关键词： Floating offshore wind turbine Tower shadow effect Atmospheric boundary layer inflow JONSWAP wave Wind turbine wake

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Cosmic Dust in Suzhou A-Type Granite

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Science China Chemistry 1994年第9期37卷 1119-1129页

作者：王尔康万玉秋朱政胡中为林承毅周剑雄倪邦发 Department of Earth Sciences Nanjing University Nanjing 210008 PRC Department of Astronomy Nanjing University Nanjing 210008 PRC Centre for Modern Analysis Nanjing University Nanjing 210008 PRC Geological Academy of China Beijing 100037 PRC Institute of Atomic Energy of China Beijing 102413 PRC

A large number of microspherules have been extracted from Suzhou A-type granite bymeans of heavy *** natural surfaces and part sections of 539 microspherules have been observed bySEM.457 microspherules have been determined by EDX,with some of them by EPMA,XRD and *** results suggest these spherules are of ablated cosmic *** them silicate glassy microspheruleshave been highly enriched in REE and other lithophile refractory trace elements,and REE abundance patternfavors a meteoritic origin as a roughly flat *** has been first found in these glassy *** composition of these iron spherules is similar to those of the ablated cosmic dust from deepsea and polar *** Fe-Ni spherules and spherules composed of troilite have also been *** isprobably the first report on various types of cosmic dust extracted from granite.

关键词： cosmic dust microspherule granite Suzhou

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Study of Nano-crystalline Silicon Films

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Science China Mathematics 1993年第2期36卷 248-256页

作者：何宇亮刘湘娜王志超程光煦王路春于是东 Department of Physics Nanjing University Nanjing 210008 PRC Laboratory of Solid State Microstructures Nanjing University Nanjing 210008 PRC

By using strong hydrogen dilution of silane in PECVD system and controlling the deposition parameters strictly, we have prepared a-Si:H and nc-Si:H as well as μc-Si:H films respectively. The structural characters of nc-Si: H films detected by means of HREM, Raman and X-ray diffraction spectra are identified as coinciding with the known definition of nanometer solids. The unique electrical and optical properties of nc-Si:H films are considered as the consequence of its novel structures.

关键词： nano-crystalline silicon deposition mierostructure.

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Sm-Nd Isotopic Signatures and Significance of the Precambrian-Cambrian Seawater in China

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Science China Chemistry 1994年第10期37卷 1242-1251页

作者：杨杰东孙卫国王银喜王宗哲 Center of Modern Analysis Nanjing UniversityNanjing 210008PRC nanjing Institute of Geology and Palaeontology Academia SinicaNanjing 210008PRC

Sm-Nd isotopic determination on small shelly fossils and collophanites collected from 3 Precambrian-Cambrian boundary sections,namely Meishucun of Jinning in Yunnan,Maidiping of Emei in Sichuan and Wushi of Kalpin in Xinjiang,shows that the seawater masses of these three remotely separated areas were co-oceanic in the Precambrian-Cambrian transitional period,with a common seawater ε_(Nd)(T) val- ue of -6.6±*** ε_(Nd)(T) value of the China's seawater ranges from -5.7 to-6.6 during the period from 610 Ma *** 500 Ma *** research suggests that there could be an 'Asiaustralian Ocean' be- sides the Panthalassa Ocean and the Iapetus Ocean at that time,and the China's seawater possibly belonged to the Asiaustralian *** Sm-Nd model age of the determined samples is about 1.8 Ga,which reflects the mean age of the continental source areas around the China's seawater.

关键词： Precambrian-Cambrian boundary paleo-ocean fossil isotope

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Relatively Flat Envelopes

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Science China Mathematics 1994年第12期37卷 1418-1427页

作者：丁南庆 Department of Mathematics Nanjing University Nanjing 210008 PRC

The aim of this paper is to investigate relatively flat envelopes. A necessary and sufficient condition is given for a relatively-finitely presented module to have a (mono-morphic or epic) relatively flat envelope. Then those rings are characterized whose every relatively-finitely presented module has a relatively flat envelope which coincides with its in-jective envelope. Some known results are obtained as corollaries.

关键词： relatively flat module relatively coherent ring envelope self-injective ring.

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Domain Structures in Minerals

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Science China Chemistry 1993年第8期36卷 1019-1024,1026页

作者：徐惠芳徐洪武罗谷风 Department of Earth Sciences Nanjing University Nanjing 210008 PRC Department of Silicate Engineering Nanjing Institute of Chemical Technology Nanjing 210009 PRC

Domain structures in mineral crystals could be categorized into three groups and several subgroups within each group, based on characteristics of domain structures and mechanisms causing domain structures: (ⅰ) domain structures constituted by domains with the same (or identical) crystal structure and chemical composition, including anti-phase domain structures, twinning domain structures, inversion domain structures, and translationtwinning domain structures; (ⅱ) domain structures constituted by two or more than two kinds of domains with the same chemical composition but different crystal structures; and (ⅲ) domain structures constituted by two kinds of compositional and structural different domains, including exsolution-induced and polysomatic reaction-induced domain structures. Different types of domain structures may display different phenomena in their TEM images and SAED patterns, due to different crystallographic characteristics of different domain structures. The domain structures in minerals may affect physical properties, chemical composition, and thermodynamic properties of minerals, and can also indicate the evolution history of minerals.

关键词： mineral domain structure transmission electron microscopic image electron diffraction pattern.

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Study on Mechanical Parameters of Rocks and Regional Layer-Slip Systems in Hunan-Jiangxi Areas

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Science China Chemistry 1993年第8期36卷 962-975页

作者：孙岩施泽进勾佛仪 Department of Earth Sciences Nanjing University Nanjing 210008 PRC Department of Engineering and Mechanics Hehai University Nanjing 210024 PRC

In order to quantitatively study layerslip-dipslip, nappe-glide structure systems in the Hunan-Jiangxiareas, samples with divided layers of these classical cross sections in the studied area were selected, and various physicomechanical parameters were systematically determined. Furthermore, five regional layer-slip systems of the basement and the cover strata were scientifically divided in the Middle Yangzi area, and they have been synthetically compared with the determined parameters in the Lower Yangzi area. Overall, the parameter value of a sliplayer presenting relative plasticity, ductility and viscosity is higher than a non-slip layer presenting relative elasticity, brittleness and rigidity, except the value of the Poission's ratio of the rock and the determined temperature of the inclusion, other parameters (such as the uniaxial pressure strength of the rock, the elastic module, the density and the elastic wave velocity) are all lower. On the basis of the study, the authors still further explain a pneumatic cushion effect of the slip-layer and the research significance.

关键词： rock mechanics layer-slip system Hunan-Jiangxi areas pneumatic cushion effect.

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Solution and Diffusion Behavior of Pure Gases and Gas Mixtures in Glassy Polymer Membranes

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Science China Chemistry 1994年第5期37卷 522-530页

作者：庄震万卫伟时钧 nanjing Institute of Chemical Technology Nanjing 210009 PRC

A general model for the solution and diffusion behavior in pure gas-polymer membrane systems and gas mixture-polymer membrane systems has been developed. Proved by experiments on different glassy and rubbery polymer membranes at various temperatures and pressures, this model can achieve the prediction of permeation behavior of pure gases and gas mixtures in polymer membranes only using the model parameters obtained from experiments on pure gases. The calculated results are in good agreement with experimental.

关键词： gas permeation polymer membrane solution and diffusion transport mechanism.

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