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Journal of Oceanology and limnology 2024年第3期42卷 709-714页

作者： Xudong ZHANG xiaofeng li Key Laboratory of Ocean Observation and Forecasting Key Laboratory of Ocean Circulation and WavesInstitute of OceanologyChinese Academy of SciencesQingdao 266071China

Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global *** remote sensing images have played an essential role in studying ISWs,they mainly exploit two-dimensional image ***,with the launch of the surface water ocean topography(SWOT)satellite on December 16,2022,a unique opportunity has emerged to capture wide-swath three-dimensional ISW-induced sea surface *** this study,we examine ISWs in the Andaman Sea using data from the Ka-band Radar Interferometer(KaRIN),a crucial sensor onboard *** not only provides backscattering satellite images but also employs synthetic aperture interferometry techniques to retrieve wide-swath two-dimensional sea surface height *** observations in the Andaman Sea revealed the presence of ISWs characterized by dark-bright strips and surface elevation *** surface soliton has an amplitude of 0.32 m,resulting in an estimation of ISW amplitude of approximately 60 *** contrast to traditional two-dimensional satellite images or nadir-looking altimetry data,the SWOT mission’s capability to capture threedimensional sea surface information represents a significant *** breakthrough holds substantial promise for ISW studies,particularly in the context of ISW amplitude inversion.

关键词： internal solitary wave(ISW) surface water ocean topography(SWOT) altimeter

Force-position collaborative optimization of rope-driven snake manipulator for capturing non-cooperative space targets

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 369-384页

作者： li, xiaofeng Tian, Jian Wei, Cheng Cao, Xibin Harbin Inst Technol Sch Astronaut Harbin 150001 Peoples R China China Acad Space Technol Beijing Inst Spacecraft Syst Engn Beijing 100094 Peoples R China

With the rapid development of space activities, non-cooperative space targets increase swiftly, such as failed satellites and upper stages, threating normal spacecrafts seriously. As there are some problems in the capture process, such as excessive collision and fast tumbling of targets, manipulator with redundant Degrees of Freedom (DOFs) can be used to improve the compliance and therefore solve these problems. The Rope-Driven Snake Manipulator (RDSM) is a combination of hyper-redundant DOFs and better compliance, and therefore it is suitable for capturing mission. In this paper, a snake manipulator mechanism is designed, and the complete kinematic model and system dynamic model considering RDSM, target and contact is established. Then, to obtain the configuration of joint with hyper-redundant DOFs, an improved motion dexterity index is proposed as the joint motion optimization target. Besides, the force-position collaborative optimization index is designed to adjust active stiffness, and the impedance control method based on the modified index is used to capture the space target. Finally, the proposed force-position collaborative optimization method is verified by virtual prototype co-simulation. The results demonstrate that based on the proposed method, the collision force is reduced by about 25% compared to normal impedance control, showing higher safety. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Capturing non-cooperative space targets Rope-driven snake manipu- lator Force-position collaborative optimization Redundant degrees of free- dom Active stiffness adjustment DUAL-ARM SPACE IMPEDANCE CONTROL ROBOT DEXTERITY INDEX

Effect of Direct Aging on Corrosion Behavior of AlSi10Mg Alloy Fabricated by Laser Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 266-282页

作者： Zhen Zhang Zhanyong Zhao xiaofeng li Beibei Wang Peikang Bai Shanxi Key Laboratory of Controlled Metal Solidification and Precision Manufacturing School of Materials Science and EngineeringNorth University of ChinaTaiyuan030051China Technical Center Taiyuan Iron and Steel(Group)Co.LtdTaiyuan030003China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Effect of direct aging of 170℃on corrosion behavior of laser powder bed fused AlSi10Mg(LPBF-AlSi10Mg)was studied by microstructure analysis,electrochemical analysis and X-ray photoelectron *** results show that direct aging of 170℃has little effect on melt pool and Si cellular structure,but promotes the precipitation of nano-Si particles and releases the residual *** increasing aging time from 0 to 4 h to 24 h,the corrosion property of the LPBF-AlSi10Mg is deteriorated,which is evidenced by increased corrosion current density and decreased pitting potential and polarization *** increasing the aging time,the thickness of the oxide film formed on surface of the LPBF-AlSi10Mg *** Si content of the oxide film of the sample aging for 4 h is the lowest,9.42 at.%,and it is the highest,18.62 at.%,for the sample aging for 24 *** electrochemical noise analysis reveals that the middle-frequency contribution of the Hilbert spectrum is responsible for the deteriorated corrosion performance,which corresponds to metastable pitting initiated by nano-Si particles.

关键词： Laser powder bed fusion AlSi10Mg Direct aging Corrosion

Alterations in expression and localization of POMGNT1 in the APP/PS1 mouse model of Alzheimer’s disease

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Genes & Diseases 2024年第5期11卷 55-58页

作者： Hanxiao Jiang Yuxue Feng Xia Hao Guiqiong He xiaofeng li Department of Neurology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 401336China Chongqing Key Laboratory of Neurobiology Chongqing Medical UniversityChongqing 400016China Department of Anatomy Chongqing Medical UniversityChongqing 400016China Department of Neurology The Fifth People’s Hospital of ChongqingChongqing 400062China

Alzheimer’s disease(AD)is a complex and progressive neurodegenerative disorder that causes dementia in the aging *** of the characteristic pathologic hallmarks of AD is the senile plaques,composed of the accumulation of *** b-amyloid results from the cleavage of transmembrane b-amyloid precursor protein(APP)by b-secretases and g-secretases,sequentially.O-mannosylation was found essential for the normal function of APP in Saccharomyces cerevisiae.1 Protein Olinked mannose b1,2-N-acetyl-glucosaminyltransferase 1(POMGNT1)is a glycosyltransferase crucial for the elongation of O-mannosyl glycans and catalyzes the transfer of Nacetylglucosamine from uridine 50-diphosphate-N-acetylglucosamine to O-mannose of glycoproteins.

关键词： APP/PS1 Alzheimer amyloid

FPSblo:A Blockchain Network Transmission Model Utilizing Farthest Point Sampling

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Computers, Materials & Continua 2024年第2期78卷 2491-2509页

作者： Longle Cheng Xiru li Shiyu Fang Wansu Pan He Zhao Haibo Tan xiaofeng li Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230026China

Peer-to-peer(P2P)overlay networks provide message transmission capabilities for blockchain *** data transmission efficiency in P2P networks can greatly enhance the performance of blockchain ***,traditional blockchain P2P networks face a common challenge where there is often a mismatch between the upper-layer traffic requirements and the underlying physical network *** mismatch results in redundant data transmission and inefficient routing,severely constraining the scalability of blockchain *** address these pressing issues,we propose FPSblo,an efficient transmission method for blockchain *** inspiration for FPSblo stems from the Farthest Point Sampling(FPS)algorithm,a well-established technique widely utilized in point cloud image *** this work,we analogize blockchain nodes to points in a point cloud image and select a representative set of nodes to prioritize message forwarding so that messages reach the network edge quickly and are evenly ***,we compare our model with the Kadcast transmission model,which is a classic improvement model for blockchain P2P transmission networks,the experimental findings show that the FPSblo model reduces 34.8%of transmission redundancy and reduces the overload rate by 37.6%.By conducting experimental analysis,the FPS-BT model enhances the transmission capabilities of the P2P network in blockchain.

关键词： Blockchain P2P networks scalability farthest point sampling

Spatiotemporal Changes of Snow Depth in Western Jilin,China from 1987 to 2018

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Chinese Geographical Science 2024年第2期34卷 357-368页

作者： WEI Yanlin li xiaofeng GU lingjia ZHENG Zhaojun ZHENG Xingming JIANG Tao Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchun 130102China College of Electronic Science and Engineering Jilin UniversityChangchun 130012 National Meteorological Satellite Meteorological Center Beijing 100081China

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming ***,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse ***,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD *** results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/*** snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air *** correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and *** March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo ***,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.

关键词： snow cover snow depth(SD) climate changes passive microwave(PMW) western Jilin,China

Low Loss and Low EMI Noise Trench IGBT with Shallow Emitter Trench Controlled P-Type Dummy Region

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Chinese Journal of Electronics 2024年第2期33卷 326-335页

作者： Jinping ZHANG xiaofeng li Rongrong ZHU Kang WANG Bo ZHANG State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China (UESTC) Institute of Electronic and Information Engineering of UESTC in Guangdong

A novel trench insulated gate bipolar transistor（TIGBT） with a shallow emitter trench controlled P-type dummy region（STCP-TIGBT） is *** with the conventional TIGBT with floating P-type dummy region（CFP-TIGBT） and TIGBT with floating P-type dummy region and normally on hole path（HFPTIGBT）,the proposed STCP structure not only speeds up the extraction of excessive holes in the turn-off process but also reduces the Miller plateau charge(Qgc).Therefore,both the power loss and electromagnetic interference（EMI） noise are significantly *** results show that the Qgcof the proposed device is only 501 nC/cm2,which is reduced by 58.5% and 26.4% when compared to the CFP-TIGBT and HFP-TIGBT,*** same on-state voltage drop(Vceon) of 1.02 V,the turn-off loss(Eoff) of the proposed device is 13.49 mJ/cm2,which is 64.6%and 67.6% less than those of the CFP-TIGBT and HFP-TIGBT,***,the reverse recovery dVak/dt of the freewheeling diode at same turn-on loss(Eon) of 31.8 mJ/cm2for the proposed STCP-TIGBT is only 2.15 kV/μs,which is reduced by 91.3% and 57.2% when compared to 24.69 kV/μs and 5.02 kV/μs for the CFP-TIGBT and HFPTIGBT,*** reduced dV/dt significantly suppresses the electromagnetic interference noise generated by the proposed device.

关键词： Insulated gate bipolar transistors Electrodes Annealing Simulation Electromagnetic interference Noise Voltage

A Multi-Constraint Path Optimization Scheme Based on Information Fusion in Software Defined Network

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Computers, Materials & Continua 2024年第4期79卷 1399-1418页

作者： Jinlin Xu Wansu Pan Longle Cheng Haibo Tan Munan Yuan xiaofeng li Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230026China

The existingmultipath routing in Software Defined Network (SDN) is relatively blind and inefficient, and there is alack of cooperation between the terminal and network sides, making it difficult to achieve dynamic adaptationof service requirements and network resources. To address these issues, we propose a multi-constraint pathoptimization scheme based on information fusion in SDN. The proposed scheme collects network topology andnetwork state information on the network side and computes disjoint paths between end hosts. It uses the FuzzyAnalytic Hierarchy Process (FAHP) to calculate the weight coefficients of multiple constrained parameters andconstructs a composite quality evaluation function for the paths to determine the priority of the disjoint paths. TheSDN controller extracts the service attributes by analyzing the packet header and selects the optimal path for flowrule forwarding. Furthermore, the service attributes are fed back to the path composite quality evaluation function,and the path priority is dynamically adjusted to achieve dynamic adaptation between service requirements andnetwork status. By continuously monitoring and analyzing the service attributes, the scheme can ensure optimalrouting decisions in response to varying network conditions and evolving service demands. The experimentalresults demonstrated that the proposed scheme can effectively improve average throughput and link utilizationwhile meeting the Quality of Service (QoS) requirements of various applications.

关键词： SDN multi-constraint path information fusion FAHP

The Geology, Fluid Inclusions, and O-S Isotopes of the Mibei Gold Deposit, Hunan Province, Southern China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 992-1006页

作者： XUE Wenhao liANG Yayun li xiaofeng li Mingyi XIE Wenbo PENG Xue XIA Rui HE Hongsheng XIAO Jincheng School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Geophysical and Geochemical Survey Institute of Hunan Changsha 410116China New Geological Energy Exploration and Development Engineering Technology Research Center of Hunan Changsha 410116China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China Comprehensive Survey Command Center for Natural Resources China Geological SurveyBeijing 100055China

The Mibei gold deposit,located in the southwestern part of the Xuefengshan uplift zone,the middle section of the Jiangnan orogenic belt in southern China,has estimated gold resources of approximately seven *** deposit is primarily a quartz vein-type gold deposit,with ore bodies occurring mainly within Neoproterozoic *** main metallic minerals in the ore are pyrite,chalcopyrite,and *** this study,the petrography and microthermometry of ore-forming fluid inclusions,oxygen isotopes of gold-bearing quartz,and sulfur isotopes of goldbearing sulfides and arsenopyrite were *** types of fluid inclusions were identified:type Ⅰa three-phase inclusions comprising vapor and two phases of liquids(V_(CO_(2))+L_(CO_(2))+L_(H2O)),type Ⅰb two-phase liquids(L_(CO_(2))+L_(H2O)),typeⅡ two-phase vapor-rich inclusions(V/V+L> 50%),and type Ⅲ pure liquid *** Ⅰ inclusions were heated uniformly to the liquid phase,type Ⅱ inclusions were heated uniformly to the gas phase,and type Ⅲ inclusions were heated without *** general,the temperature range of homogenization to liquid phase of fluid inclusions in the Mibei gold deposit is 204-227℃.The salinity of the inclusion ranges from 4.6 to 12.2 wt% NaCl *** δ~(18)O_(SMOW) of gold-bearing quartz varies from 16.9‰ to 17.5‰.The δ~(18)O_(H2O) of gold-bearing quartz are varied from 6.5‰ to 7.5‰.The δ~(34)S values of gold-bearing pyrite range from 1.7‰ to 6.8‰.The δ~(34)S values of gold-bearing arsenopy rite range from 5.6%o to 5.9‰.Theδ~(34)S values of pyrite from wall rocks slate range from 6.4‰ to 11.6‰.This evidence implies that the ore-forming fluids of the Mibei gold deposit originated from magmatic-hydrothermal processes,mixing with minor S from the surrounding *** with the evolution of the Jiangnan orogenic belt,due to the magmatic and tectonic activities of the Xuefengshan uplift during the Caledonian period,the fault seal mechanism controlled the ore-forming p

关键词： ore-forming fluid ore genesis Mibei gold deposit Xuefengshan uplift zone Jiangnan orogenic belt

Hydrothermal synthesis of polyimide-linked covalent organic frameworks towards ultrafast and stable cathodic sodium storage

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Science China Chemistry 2024年第4期67卷 1300-1310页

作者： Xiya Yang Lei Gong Zhixin liu Qianjun Zhi Baoqiu Yu Xin Chen Kang Wang xiaofeng li Dongdong Qi Jianzhuang Jiang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Redox-active organic materials are capturing growing attention as cathode materials for sustainable alkaline metal ion ***,the storage of Na+in most organic materials-based cathodes is plagued by low capacity and unsatisfying rate performance due to their low active site densities and limited exposed active ***,two polyimide-linked covalent organic frameworks(COFs),namely HATN-PD-COF and HATN-TAB-COF,were fabricated from hydrothermal synthesis with redoxactive triphenylene-2,3,6,7,10,11-hexacarboxylic acid and aromatic amines as starting *** X-ray diffraction and electron microscopy analysis indicate the high crystalline nature of these COFs with AA stacking configuration and orderly mesoporous tunnel.N_(2) sorption measurement discloses the permanent porosity of these two COFs with a Brunauer-EmmettTeller surface area of 1,065-1,200 m^(2)g^(-1)and a large pore size of 2.0-3.1 *** intermittent titration technique and density functional theory calculations reveal the facile Na+ion diffusion along the mesoporous tunnel of these COFs with a small energy barrier of 0.13-0.40 e *** particular,the as-prepared COFs based-cathodes show ultrafast and stable Na+storage associated with their conjugated electronic structure,highly ordered mesoporous tunnel,robust structure,and redox-active C=N/C=O-rich framework as exemplified by the high reversible capacity of 210 m A h g^(-1)at 200 m A g^(-1),record-high rate performance(195 m A h g^(-1)at a high current density of 10,000 m A g^(-1))among organic electrodes and the capacity retention of nearly 91%at 10,000 m A g^(-1)after 7,000 cycles for HATN-PD-COF.

关键词： covalent organic framework sodium ion battery cathode high rate organic electrode