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Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI Shasha LI hao XU Jie YU jun MA Huijun LIU Jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-jun Chen Ze He Hong-hao Ma Lu-Qing Wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

Development review and the prospect of oil shale in-situ catalysis conversion technology

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Petroleum Science 2024年第2期21卷 1385-1395页

作者： Li Wang Chen-hao Gao Rui-Ying Xiong Xiao-jun Zhang Ji-Xiang Guo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing102200China

As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.

关键词： Oil shale In-situ catalytic technology Pyrolysis catalyst Kerogen pyrolysis mechanism

Quorum Sensing:An Emerging Role for Vibrio Infection and Host Defense

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Infectious Microbes & Diseases 2024年第2期6卷 47-55页

作者： hao-Nan Lin Xian-Hui Huang Xin-jun Miao wei-Lin Hu Yong-Liang Lou Dan-Li Xie The School of Laboratory Medicine&Life Sciences Wenzhou Medical UniversityWenzhouChina Key Laboratory of Laboratory Medicine Ministry of Education of ChinaWenzhouChina Wenzhou Key Laboratory of Sanitary Microbiology WenzhouChina Department of Emergency Wenzhou Central HospitalWenzhouZhejiangChina Department of Microbiology School of MedicineZhejiang UniversityHangzhouChina Zhuji Institute of Biomedical Research School of PharmacyWenzhou Medical UniversityZhujiChina

Quorum sensing(QS)is a mechanism that allows bacteria to regulate various physiological and biochemical functions by secreting,sensing and responding to signaling molecules called autoinducers(AIs).In Vibrio species,QS plays a crucial role in modulating different biological *** can influence the formation of biofilms,which are communities of bacteria encased in a protective *** also controls flagella formation and motility,ensuring that Vibrio *** move efficiently in response to environmental ***ally,QS in Vibrio *** the production of different virulence factors based on cell *** enables the bacteria to adjust their virulence strategies accordingly,enhancing *** also influences the interaction between Vibrio *** their ***ing infection by Vibrio spp.,QS can affect the host immune response and colonization *** the role of QS in these interactions is crucial for unraveling the complex dynamics between Vibrio *** the *** summary,research on QS in Vibrio *** revealed its significance in regulating various biological phenotypes,controlling virulence factor production and affecting host de*** provides valuable insights into the intricate mechanisms underlying microbial behavior,host adaptation and Vibrio ***.

关键词： quorum sensing Vibrio species biological phenotype bacterial virulence host defense

Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19

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Advances in Atmospheric Sciences 2024年第1期41卷 84-96页

作者： Zhiding ZHANG Xu YUE hao ZHOU jun ZHU Yadong LEI Chenguang TIAN Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&Technology(NUIST)Nanjing 210044China Climate Change Research Center Institute of Atmospheric Physics(IAP)Chinese Academy of Sciences(CAS)Beijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China

The pan-Arctic is confronted with air pollution transported from lower *** have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less ***,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during *** show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,*** all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic *** aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the *** contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle *** trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols *** affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming.

关键词： diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity

Effects of soil metal(loid)s pollution on microbial activities and environmental risks in an abandoned chemical smelting site

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Journal of Environmental Sciences 2024年第9期143卷 60-70页

作者： hao Li jun Yao Jianli Liu Ning Min Geoffrey Sunahara Dongyang Men Robert Duran School of Water Resources and Environment Research Center of Environmental Science and EngineeringChina University of Geosciences(Beijing)Beijing 100083China Department of Natural Resource Sciences McGill University21111Lakeshore DriveSte-Anne-de-BellevueQuebecH9X 3V9Canada Equipe Environnement et Microbiologie MELODY groupUniversitéde Pau et des Pays de l’AdourE2S-UPPAIPREM UMR CNRS 5254BP 115564013 Pau CedexFrance

Abandoned chemical smelting sites containing toxic substances can seriously threaten and pose a risk to the surrounding ecological *** samples were collected from different depths(0 to 13 m)and analyzed for metal(loid)s content and fractionation,as well as microbial *** potential ecological risk indices for the different soil depths(ordered from high to low)were:1 m(D-1)>surface(S-0)>5 m(D-5)>13 m(D-13)>9 m(D-9),ranging between 1840.65-13,089.62,and representing extremely high environmental risks,of which Cd(and probably not arsenic)contributed to the highest environmental risk.A modified combined pollution risk index(MCR)combining total content and mobile proportion of metal(loid)s,and relative toxicities,was used to evaluate the degree of contamination and potential environmental *** the near-surface samples(S-0 and D-1 layers),the MCR considered that As,Cd,Pb,Sb,and Zn achieved high and alarming degrees of contamination,whereas Fe,Mn,and Ti were negligible or low to moderate pollution *** microcalorimetry and enzymatic activity measurements of contaminated soil samples were used to assess the microbial metabolic activity *** analysis elucidated the relationship between metal(loid)s exchangeable fraction or content and microbial activity characteristics(p<0.05).The microbial metabolic activity in the D-1 layer was low presumably due to heavy metal *** activity indicators and microcalorimetric growth rate(k)measurements were considered sensitive indicators to reflect the soil microbial activities in abandoned chemical smelting sites.

关键词： Abandoned chemical smelting sites Microbial activities Modified combined pollution risk Microcalorimetry Enzymatic activities

Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： Wen-Dong Liu Xiao Tang jun-An Feng Chao-Yue Zhang hao Liu Chuan Shi Xiao-Xian Zhao Jian-jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application ***,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of *** response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of ***,vacancy engineering has gained the attention of researchers due to its unique electronic *** review aims to analyze the application of vacancy engineering in ***,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been ***,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,*** latest applications of vacancy engineering in LSBs are also summarized in this ***,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

A 27 GHz,simple 2-bit 1×8 phased array

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Journal of Electronic Science and Technology 2024年第3期22卷 26-34页

作者： jun-Xian Liu Yun-Ying Man hao Yang Peng Yang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This study demonstrates a simple 2-bit phased array operating at 27 GHz that supports one-dimensional beam scanning with left-handed circular polarization(LHCP).The antenna is constructed using a compact four-layer printed circuit board(PCB)structure,consisting of a 90°phase shifter layer with microstrip structures,a ground(GND)layer,a direct current(DC)control layer,and a circularly polarized annular radiation patch layer with 1-bit phase *** on the proposed unit structure,a 1×8 array with half-wavelength inter-element spacing was designed and *** results show that the array achieves a peak gain of 10.23 dBi and is capable of beam scanning within±50°.

关键词： 27 GHz 2-bit P-i-n diodes Phased array Reconfigurable antennas

Genome-wide analysis of Panonychus citrimicro RNAs witha focus on potential insecticidal activity of 4 micro RNAs toeggs and nymphs

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Insect Science 2024年第2期31卷 354-370页

作者： Chuan-Zhen Li Yu-Hang Liu Deng Pan Meng-hao Xia Qiang Zhang Yu-Chuang Li Guo-Rui Yuan Jin-jun Wang wei Dou Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionAcademy of Agricultural SciencesSouthwestUniversityChongqingChina Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River(Ministry of Education) Academy of Agricultural SciencesSouthwest UniversityChongqingChina

Panonychus citriMcGregor(Acari:Tetranychidae),a destructive citrus pest,causes considerable annual economic losses due to its short lifespan and rapid ***(miRNA)-induced RNA interference is a promising approachfor pest control because of endogenous regulation of pest growth and *** for miRNAs with potential insecticidal activity ***,genome-wide analysis ofmiRNAs at different developmental stages was conducted,resulting in the identificationof 136 miRNAs,including 73 known and 63 novel miRNAs.A total of 17 isomiRNAsand 12 duplicated miRNAs were ***-1 and miR-252-5p were identified asreference miRNAs *** *** on differential expressionanalysis,treatments with miR-let-7a and miR-315 mimics and the miR-let-7a antagomirsignificantly reduced the egg hatch rate and resulted in abnormal egg ***-expression or downregulation of miR-34-5p and miR-305-5p through feeding significantlydecreased the adult eclosion rate and caused molting *** 4 miRNAs,miR-let-7a,miR-315,miR-34-5p,and miR-305-5p,had important regulatory functions and insectici-dal properties in egg hatching and adult *** general,these data advance our un-derstanding of miRNAs in mite biology,which can assist future studies on insect-specificmiRNA-based green pest control technology.

关键词： growth and development microRNAs Panonychus citri referencemiRNAs regulation small RNA libraries