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Decoding the inconsistency of six cropland maps in china

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The Crop Journal 2024年第1期12卷 281-294页

作者： Yifeng Cui Ronggao liu Zhichao li Chao Zhang xiao-Peng Song jilin Yang Le Yu Mengxi Chen Jinwei Dong Institute of Geographic sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China university of Chinese Academy of sciences Beijing 100049China Department of Geographical sciences University of MarylandCollege ParkMD 20740USA college of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Beijing 100084China Tsinghua university(Department of earth System Science)-Xi’an Institute of Surveying and Mapping Joint Research Center for Next-Generation Smart Mapping Beijing 100084China Institute of Remote Sensing and Geographic Information System Peking UniversityBeijing 100871China Department of Forest and Conservation sciences University of British ColumbiaVancouverBCV6T 1Z4Canada

Accurate cropland information is critical for agricultural planning and production,especially in foodstressed countries like *** widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades,considerable discrepancies exist among these products both in total area and in spatial distribution of croplands,impeding further applications of these *** factors influencing their inconsistency are also *** this study,we evaluated the consistency and accuracy of six cropland maps widely used in china in circa 2020,including three state-of-the-art 10-m products(i.e.,Google Dynamic World,ESRI Land Cover,and ESA WorldCover)and three 30-m ones(i.e.,GLC_FCS30,GlobeLand 30,and CLCD).We also investigated the effects of landscape fragmentation,climate,and agricultural *** using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy(92.3%).These maps collectively overestimated Chinese cropland area by up to 56%.Up to 37%of the land showed spatial inconsistency among the maps,concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps,cropland fragmentation and management practices such as *** work shed light on the promotion of future cropland mapping efforts,especially in highly inconsistent regions.

关键词： Consistency and accuracy 10-and 30 m Cropland mapping Agricultural management china

Along-track Calibration of the Zhurong Rover Magnetometer

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Science china earth sciences 2024年第2期67卷 552-565页

作者： Hao LUO Aimin DU Yasong GE Ying ZHANG Haiying li lin TIAN Kuixiang ZHANG Shuquan sun lin ZHAO Zhi li xiao feng CAS Engineering Laboratory for Deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China college of earth Science University of Chinese Academy of SciencesBeijing100049China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China

As part of the Chinese Tianwen-1 mission,the Zhurong Rover began its scientific investigation in the southern Utopia Planitia after its successful landing in 15 May,*** Zhurong Rover magnetometer(RoMAG),one of the six payloads onboard the rover,includes two identical high-sensitivity triaxial fluxgate magnetometers and can implement mobile magnetic measurements on the surface of *** a rover magnetic compensation procedure was conducted to remove the magnetic interferences pre-launch,due to the different state of the payloads and electric power system such as the solar panel,an along-track calibration of the magnetometer is necessary to obtain a more accurate Martian magnetic *** methods,mast yaw rotations and Rover yaw rotations were utilized separately to determine the Martian horizontal magnetic *** show that the Martian horizontal magnetic components determined by the two methods are in good agreement,with the root mean square deviation less than 2.0 *** vertical component was also constrained through the pitch movements of the mast by assuming the interferences field distributes like a dipole field.A linear correlation between magnetic field measurements and the solar array currents was derived to calibrate the body field during the regular *** conclude that more accurate measurements could be made when applying the calibration results in the magnetic survey on the surface of Mars.

关键词： The Zhurong Rover Magnetometer Along-track calibration Remnant magnetization

New material of Coniopteris simplex from the Middle Jurassic of the Ordos Basin,Inner Mongolia,china and implications on its spatio-temporal distribution and paleogeography

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Journal of Palaeogeography 2024年第2期13卷 199-211页

作者： Yun-feng li Chang-Lu Zhang Fei liang xiao Tan Fan-Hao Gong Chun-lin sun Tao li Yu-ling Na Research Center of Paleontology and Stratigraphy Jilin UniversityChangchun 130026Jilin ProvinceChina college of earth sciences Jilin UniversityChangchun 130061Jilin ProvinceChina college of Paleontology Shenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Key Lab of Evolution of Past life in NE Asia Ministry of Natural ResourcesShenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Shenyang Center of Geological Survey China Geological SurveyShenyang 110034Liaoning ProvinceChina

Coniopteris simplex is a common component in many Jurassic ***,due to morphological variations in sterile fronds and incomplete preservation of reproductive organs,its classification has been controversial for a long ***,we present new material collected from the Middle Jurassic Yan’an Formation in the Ordos Basin,Inner *** new material reveals important morphological characters,including hemi-dimorphic fronds,two forms of sterile pinnae,short-stalked sori and sporangia on fertile fronds,annulus of sporangium composed of about 30 cells,in situ rounded triangular spores with protruded suture,and the lips of trilete laesura encircled by one or two rows of small *** on these observations,we emended the diagnosis of this common *** spatio-temporal distribution of Coniopteris simplex shows that the iconic species was restricted to the paleolatitudes ranging from 19.5°N to 48.9°N in the Northern Hemisphere during the Early—Late Jurassic,mainly distributed in the tropical to paratropical zones,and the paleolongitude ranging from 9.6°E to 129.3°E,which may be limited by the opening of the Viking Corridor and the splitting of the Central Atlantic Ocean.

关键词： Coniopteris simplex Yan'an Formation Middle Jurassic Inner Mongolia Paleogeography

A Novel Gymnosperm Wood from the Lopingian(Late Permian)in Zhangzi,Shanxi,North china and Its Paleoecological and Paleogeographic Implications

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Journal of earth Science 2024年第1期35卷 167-176页

作者： xiao Shi Jianxin Yu yuewu sun Zhen Xu Hui li college of earth sciences Jilin UniversityChangchun 130061China International Center of Future Science Dinosaur Evolution Research CenterJilin UniversityChangchun 130012China State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China Research Center of Palaeontology and Stratigraphy Jilin UniversityChangchun 130026China Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China

The Permian-Triassic transition saw extreme climatic changes that severely impacted the terrestrial *** plants,particularly fossil woods,are sensitive to climatic changes,and they,therefore,are unique materials revealing extreme environmental and climatic changes on land at that *** conifer woods were discovered in the Lopingian(Late Permian)strata of the sunjiagou Formation in Shanxi Province,North *** newly finding permineralized woods record the unique landscape of Lopingian North *** represent a new conifer genus and species:Shanxiopitys zhangziensis *** *** of growth pattern and anatomical characteristics of the fossil woods indicate these trees grew under optimal growing conditions,and without seasonal growth ***,climate signals from leaf fossils,vertebrate fossils and sedimentary evidences indicate a strongly seasonal climate in North china during the ***,it is speculated that these trees likely lived in the gallery forests,which were distributed along the paleo-rivers within a seasonal landscape in the central North china block during the Lopingian.

关键词： Shanxiopitys zhangziensis gen.et sp.nov. wood ecology geography gallery forest Lopingian North china

Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction

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Journal of Energy Chemistry 2024年第4期91卷 475-483页

作者： xiao-Chen sun Xing-Chi li Ze-Wei Xie Chen-yue Yuan De-Jiu Wang Qian Zhang xiao-Yu Guo Hao Dong Hai-Chao liu Ya-Wen Zhang Beijing National Laboratory for Molecular sciences(BNLMS) State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Beijing National Laboratory for Molecular sciences(BNLMS) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Beijing National Laboratory for Molecular sciences(BNLMS) State Key Laboratory for Structural Chemistry of Stable and Unstable SpeciesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported ***,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)*** obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1).s^(-1)at 300℃and high stability of about 120 *** on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction *** Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,*** collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported *** study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions.

关键词： Cu-based catalyst MOF derivative Water-gas shift reaction Metal-support interaction

Laser manufacturing of spatial resolution approaching quantum limit

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light(Science & Applications) 2024年第3期13卷 421-428页

作者： xiao-Jie Wang Hong-Hua Fang Zhen-Ze li Dan Wang Hong-Bo sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size oflications.

关键词： quantum limit resolution

Metallurgy and Solidification Microstructure Control of Fusion-Based Additive Manufacturing Fabricated Metallic Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 29-53页

作者： Qiang li Xing-Ran li Bai-Xin Dong xiao-Long Zhang Shi-li Shu feng Qiu Lai-Chang Zhang Zhi-Hui Zhang Key Laboratory of Bionic Engineering(Ministry of Education) and College of Bionic Science and EngineeringJilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130025China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

The metal-based additive manufacturing(AM),also referred to as metal 3D printing,has drawn particular interest because it enables direct creation,aided by computationally-directed path design,of intricate components with site-specific compositions and geometrical requirements as well as low buy-to-fly *** the last two decades,the objective of this revolutionary technology has been shifting from only“rapid prototyping”to advanced manufacturing of special high-end products or devices,which,in many aspects,outperform conventional manufacturing *** fusion-based AM,significant progress has been achieved in understanding the processing window of macroscopic scales,non-equilibrium metallurgy of mesoscale scales,and grain evolution of microscopic *** the versatile capacity of AM facilitates new avenues for discovering advanced materials and structures,their potential has still not been fully *** the unique non-equilibrium solidification during the AM process,coarse columnar grains with strong textures are usually developed along the build direction,which downgrades the mechanical *** push the limits of this digital manufacturing,this review attempts to provide in-depth and comprehensive overviews of the recent progress in understanding the evolution and control of the as-built microstructure that has been made recently and the challenges encountered during the AM process.

关键词： Additive manufacturing Temperature field Microstructure control Nanoparticles Functionally graded materials

Discovery of eclogite and its geological significance in Qiangtang area, central Tibet

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Science Bulletin 2006年第9期51卷 1095-1100页

作者： li Cai1, ZHAI Qingguo2, DONG Yongsheng1 & HUANG xiaopeng11. college of earth sciences, jilin university, changchun 130061, china 2. Institute of Geology, Chinese Academy of Geological sciences, Bei- jing 100037, china college of earth sciences Jilin University Changchun 130061 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Eclogite is first discovered from Qiang- tang area, central Tibet, which occurs as a lens in the high-pressure metamorphic belt comprising glauco- phane-muscovite schist and garnet-muscovite schist, along the south margin of Lungmu Co-Shuanghu Paleo-Tethys suture. A glaucophane 40Ar/39Ar age of 220 Ma and a phengite 40Ar/39Ar age of 221.9 Ma have been obtained from blueschists associated with eclogite. The rock consists of garnet, omphacite, amphibole, phengite, and rutile, etc, and the jadeite content in omphacite ranges from 32.7% to 38.95%. It is estimated that the temperature of the eclogite is <500℃ and pressure varies in the range of 1.56― 2.35 GPa. The discovery of Qiangtang ecologite fur- ther supports that there is a suture zone of Indo- Chinese epoch in central Qiangtang area, and is very important for discssing the evolution of the pa- leo-ocean and paleo-plate tectonics in this area.

关键词： Qianghai-Tibet Plateau Qiangtang eclogite tectonics.

SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science china earth sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, li Cai2 & SU li3 1 Institute of Geology, Chinese Academy of Geological sciences, Beijing 100037, china 2 college of earth sciences, jilin university, changchun 130061, china 3 The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources, china university of Geo- sciences, Beijing 100083, china Institute of Geology Chinese Academy of Geological Sciences Beijing China college of earth sciences Jilin University Changchun China The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.282615 to 0.282657, with εHf(t) values of 5.02±0.28, indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope