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Drainage of paddy terraces impacts structures and soil properties in the globally important agricultural heritage of Hani Paddy Terraces,China

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International Soil and Water Conservation Research 2024年第1期12卷 64-76页

作者： ming Wang li Rong Yanbo li Jiangcheng Huang Yuanmei Jiao Xiaoyan Wei Institute of International Rivers and Eco-Security Kunming650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security Kunming650500China Power China Kunming Engineering Corporation limited Kunming650051China Department of Geography Yunnan Normal UniversityKunming650500China Yunnan Provincial Archives of Surveying and Mapping(Yunnan Provincial Geomatics Centre) Kunming650032China

Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still *** Paddy Terraces,included in Globally Important Agriculture Heritage Systems,are threatened by paddy fields ***,changes in terrace structure,the productivity of topsoil(0-20 cm),and soil water holding capacity at 0-70 cm depth were determined in a case study of Hani Paddy Terraces in Amengkong River Basin in Yuanyang County in Southwestern China,which had been converted into dryland terraces for 2-14 *** results showed that:(1)The degree of terrace structures degradation exhibited a U-shaped curve with increasing time since draining,with those drained for 5-9 years having the best structure;(2)Soil productivity index decreased first and then increased with time after conversion;(3)Maximum water holding capacity at 0-70 cm soil depth dramatically decreased after conversion and such trend became increasingly obvious with increasing time since *** study revealed that drainage of paddy terraces along with associated changes in crop and field management led to an increase in soil productivity,but degradation of terrace structures and a decrease in water holding capacity will inhibit restoration to paddy *** findings enhance the understanding of the biophysical changes due to marginalization in paddy terraces.

关键词： Hani paddy terraces Terraces marginalization Terrace structure degradation Soil productivity Water holding capacity

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Autonomous multi-drone racing method based on deep reinforcement learning

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Science China(Information Sciences) 2024年第8期67卷 35-48页

作者： Yu KANG Jian DI ming li Yunbo ZHAO Yuhui WANG Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Racing drones have attracted increasing attention due to their remarkable high speed and excellent maneuverability. However, autonomous multi-drone racing is quite difficult since it requires quick and agile flight in intricate surroundings and rich drone interaction. To address these issues, we propose a novel autonomous multi-drone racing method based on deep reinforcement learning. A new set of reward functions is proposed to make racing drones learn the racing skills of human experts. Unlike previous methods that required global information about tracks and track boundary constraints, the proposed method requires only limited localized track information within the range of its own onboard sensors. Further, the dynamic response characteristics of racing drones are incorporated into the training environment, so that the proposed method is more in line with the requirements of real drone racing scenarios. In addition, our method has a low computational cost and can meet the requirements of real-time racing. Finally, the effectiveness and superiority of the proposed method are verified by extensive comparison with the state-of-the-art methods in a series of simulations and real-world experiments.

关键词： racing drone autonomous multi-drone racing sim-to-real deep reinforcement learning Markov game

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Cooling History of Mesozoic Magmatism and Implications for Large-Scale Gold Mineralization in the Jiaodong Peninsula, East China: Constraints from T-t Paths Determined by U-Pb Thermochronology of Zircon and Apatite

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Journal of Earth Science 2024年第3期35卷 878-889页

作者： Guangyan Zhou mingchun song Long li Yan Luo DGraham Pearson Jianbo Zhou Zhengjiang Ding Xuefeng Yu Yingxin song Jie li Shiyong li Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Department of Earth&Atmospheric Sciences University of AlbertaEdmontonAlberta T6G 2E3Canada Hebei Key Laboratory of Strategic Critical Mineral Resources Hebei GEO UniversityShijiazhuang 050031China Shandong Provincial No.6 Exploration Institute of Geology and Mineral Resources Weihai 264209China College of Earth Sciences Jilin UniversityChangchun 130061China Ministry of Natural Resources Key Laboratory of Gold Mineralization Processes and Resources Utilization Key Laboratory of Metallogenic-Geologic Processes and Comprehensive Utilization of Minerals Resources in Shandong ProvinceShandong Institute of Geological SciencesJinan 250013China Shandong Nuclear Industry Geological Group 273 Yantai 264006China

The Mesozoic intrusions of the Jiaodong Peninsula,eastern China,host giant gold *** the genesis of these deposits requires the determination of the source of the parental auriferous fluid and the timing of gold mineralization,which are strongly influenced by the cooling/uplift histories of the hosting *** performed an integrated U-Pb geochronology study on both zircon and apatite from four major magmatic episodes of the Jiaodong *** zircon and apatite U-Pb ages are 156.9±1.2 and 137.2±2.4 Ma for the linglong intrusion,129.9±1.0 and 125.0±3.8 Ma for the Qujia intrusion,119.5±0.7 and 117.2±1.8 Ma for the liulinzhuang intrusion,118.6±1.0 and 111.6±1.6 Ma for the Nansu intrusion,*** coupled zircon and apatite data of these granitoids indicate a slow cooling rate(11.9°C/Ma)in the Late Jurassic,and rapid uplift and cooling(35.8-29.2°C/Ma)in the Early *** dramatically increased uplift and cooling period in the Early Cretaceous are contemporaneous with large-scale gold mineralization in the Jiaodong *** implies that thermal upwelling of asthenosphere and related tectonic extension played an important role in gold remobilization and precipitation.

关键词： magmatism geochronology zircon apatite gold deposits Jiaodong Peninsula

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Genetic relationship between formation,accumulation and migration and dispersion of peat materials in Paleogene——Take the Qiongdongnan Basin as an example

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Acta Oceanologica Sinica 2024年第4期43卷 80-91页

作者： Xiaojing li Zengxue li Dongdong Wang Guangzeng song Pingli Wang Haiyan liu Key Laboratory of Sedimentary Mineralization and Sedimentary Minerals in Shandong Province Qingdao 266590China Shandong University of Science and Technology Qingdao 266590China School of Water Conservancy and Environment University of JinanJinan 250022China

Coal-type source rocks include both coal and terrigenous marine source *** studying the distribution of secondary depressions,uplifts,as well as the characteristics of peat formation and accumulation in the northern marginal sea basin of the South China Sea,and combining them with coal formation characteristics observed in other basins,five genetic theories on the relationship between peat accumulation and dispersed organic matter accumulation are *** northern marginal sea basin of the South China Sea is characterized by“disadvantageous coals formation and favorable terrigenous marine source rocks formation.”This paper provides a distribution map of coal seams and terrigenous marine source rocks in the Qiongdongnan Basin and determines their distribution *** shows that the migration of sedimentary facies in the basins and inner depressions led to the formation and migration of the peat accumulation *** addition,the vertical migration of the peat accumulation centers led to planar migration,which is actually a type of coupling *** research results have revealed that the formation of coal-type source rock is *** marginal sea basin is composed of several fault-depression basins,with each basin developing a second order of depression and *** is no unified basin center or depositional center to be *** a result,the concentration centers of coal-forming materials also vary *** on the distribution characteristics of coal-type source rocks in different basins within the marginal sea basins of the South China Sea,the research results have practical significance and provide guidance for exploring coal-type oil and gas reservoirs in this area.

关键词： Coal-type source rock marginal sea basins migration of peat aggregation centers terrigenous marine source rock Qiongdongnan Basin

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Reduced Macrophage Uptake of Nanoparticles through Surface Modification of Polypeptides with Valine Residues

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Chinese Journal of Chemistry 2024年第11期42卷 1209-1216页

作者： Ning li Shanshan Xiao Xiaoxiong Jin Ziyuan song Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhouJiangsu215123 China

The structural and surface properties of nanomedicines play an important role in determining their biological fate. Surface chemistry of nanomedicines is one of the key parameters, where researchers used various strategies such as PEGylation to avoid the undesired clearance of nanoparticles (NPs) for enhanced targeting effect. Nevertheless, the fine-tuning of surface chemistry through polymer functionalization remains largely unexplored. In this concise report, we find that the incorporation of only 10 mol% valine residues into the surface-anchored poly(L-glutamic acid) significantly lowered the macrophage uptake of NPs. The introduction of other hydrophobic amino acid residues, however, increased the NPs internalization instead. The chirality and the side-chain structure of valine played an important role in the unexpected uptake behavior. We believe this work highlights the impact of slight changes of the surface-anchored polymer structure on the behavior of NPs, drawing people's attention to the careful design of surface chemistry to optimize the nanomedicine design.

关键词： Nanoparticles Copolymers Structure-activity relationships Surface chemistry Polypeptide Macrophage uptake

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Energy release characteristics of PTFE/Al/TiH2 reactive jet with different TiH2 content

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DEFENCE TECHNOLOGY 2024年第9期39卷 168-176页

作者： Jiang, Chunlan Zhang, Jingbo Hu, Rong Mao, liang li, ming Beijing Inst Technol State Key Lab Explos Sci & Technol Beijing 100081 Peoples R China

Titanium hydride (TiH2), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH2 reactive liners with different TiH2 content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH2 reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time, pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH2 jet initially increase and then decrease with increasing TiH2 content. When the TiH2 content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH2 content increased from 0% to 30%. Finally, combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH2 on energy release of the reactive jet is expounded. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： PTFE/Al/TiH2 Reactive materials Shaped charge Impact energy release characteristics TITANIUM

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HCRVD: A Vulnerability Detection System Based on CST-PDG Hierarchical Code Representation Learning

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Computers, Materials & Continua 2024年第6期79卷 4573-4601页

作者： Zhihui song Jinchen Xu Kewei li Zheng Shan School of Cyberspace Security Information Engineering UniversityZhengzhou450001China

Prior studies have demonstrated that deep learning-based approaches can enhance the performance of source code vulnerability detection by training neural networks to learn vulnerability patterns in code ***,due to limitations in code representation and neural network design,the validity and practicality of the model still need to be ***,due to differences in programming languages,most methods lack cross-language detection *** address these issues,in this paper,we analyze the shortcomings of previous code representations and neural *** propose a novel hierarchical code representation that combines Concrete Syntax Trees(CST)with Program Dependence Graphs(PDG).Furthermore,we introduce a Tree-Graph-Gated-Attention(TGGA)network based on gated recurrent units and attention mechanisms to build a Hierarchical Code Representation learning-based Vulnerability Detection(HCRVD)*** system enables cross-language vulnerability detection at the *** experiments show that HCRVD surpasses many competitors in vulnerability detection *** benefits from the hierarchical code representation learning method,and outperforms baseline in cross-language vulnerability detection by 9.772%and 11.819%in the C/C++and Java datasets,***,HCRVD has certain ability to detect vulnerabilities in unknown programming languages and is useful in real open-source *** shows good validity,generality and practicality.

关键词： Vulnerability detection deep learning CST-PDG code representation tree-graph-gated-attention network cross-language

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Design of new chemicals for advanced electrolytes

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Science China Chemistry 2024年第5期67卷 1378-1380页

作者： Haoran Cheng Zheng Ma Qian li Jun ming State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei 230026China

This highlight is inspired by a recent article in Nature Energy in which liu and co-workers [1] from Tsinghua University designed a new asymmetric lithium salt (i.e., lithium 1,1,1-trifluoro-N-[2-[2-(2-methoxy ethoxy)ethoxy]ethyl] methanesulfonamide (li FEA)) and applied it as a new lithium-salt additive in the conventional carbonate-based electrolyte,overcoming the incompatibility issue of carbonate electrolytes with lithium metal in lithium metal batteries (LMBs),even achieving a fast-charging feature.

关键词： lithium carbonate electrolyte

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Effi cacy of partial and complete resuscitative endovascular balloon occlusion of the aorta in the hemorrhagic shock model of liver injury

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World Journal of Emergency Medicine 2024年第1期15卷 10-15页

作者： Yi Shan Yang Zhao Chengcheng li Jianxin Gao Guogeng song Tanshi li Department of Emergency Medicine Chinese PLA Medical SchoolBeijing 100853China Department of Emergency Medicine the Sixth Medical Center of PLA General HospitalBeijing 100048China Department of Emergency Medicine School of MedicineSouth China University of TechnologyGuangzhou 510006China Department of Emergency Medicine the First Medical Center of PLA General HospitalBeijing 100853China

BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic ***,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains ***,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic ***:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)*** the cREBOA and C-pREBOA groups,the balloon was inflated for 60 *** hemodynamic and laboratory values were compared at various observation time *** samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin ***:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all Pliver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent *** tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.

关键词： Non-compressible torso hemorrhage liver injury Ischemia-reperfusion injury Resuscitative endovascular balloon occlusion of the aorta

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The First Ground-based White light Lunar Polarization Imaging:A New Kind of FeO Observation on the Near Side of the Moon

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Research in Astronomy and Astrophysics 2024年第6期24卷 1-6页

作者： Wei-Nan Wang Jin-song Ping ming-Yuan Wang Wen-Zhao Zhang Han-lin Ye Xing-Wei Han song-Feng Kou Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Astronomy Department Beijing Normal UniversityBeijing 100875China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Nanjing Institute of Astronomical Optics and Technology Chinese Academy of SciencesNanjing 210042China

Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes *** study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the *** obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the *** findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria *** the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the *** study may serve as a new diagnostic tool for the Moon.

关键词： techniques:photometric polarization methods:observational Moon

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