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High Voltage 2024年第4期9卷 786-793页

作者： Yin Zhang yan li Jin yan Chao Bian Xuan Chen Xiaoxing Zhang Hubei Engineering Research Center for Safety Monitoring of New Energy and Power Grid Equipment Hubei University of TechnologyWuhanChina State Grid Jiangsu Electric Power Co. Ltd.Ultra High Voltage BranchNanjingChina

In the detection of multi-component gas based on tunable diode laser absorption spectroscopy(TDLAS),the problem of overlapping interference between the absorption lines of each gas is often *** example,when detecting a gas mixture of sulphur dioxide(SO_(2))and thionyl fluoride(SOF_(2)),the characteristic decomposition components of SF6,there is overlapping interference in the absorption lines of the two gases,which makes it difficult to detect the concentration of gases *** view of this problem,a novel method based on support vector regression model used for TDLAS is proposed to detect two gases *** detection results show that the correlation coefficients between the concentration of SO_(2)and SOF_(2)and the average value of the second harmonic peak reached 0.992 and *** addition,through model testing,different concentrations of SO_(2)and SOF_(2)gas mixture are simultaneously detected,and the resulting maximum errors for measuring SO_(2)and SOF_(2)concentrations are less than 7.13×10^(-5)and 0.26×10^(-2).The maximum errors of the measurement results in the verification test are not more than 6.4×10^(-3)and 4.6×10^(-2).Therefore,with assistance of the novel method,the detection of multiple gases by using a single laser is achieved.

关键词： tunable diode absorption

Hard-carbon hybrid li-ion/metal anode enabled by preferred mesoporous uniform lithium growth mechanism

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Journal of Energy Chemistry 2024年第1期88卷 252-259,I0006页

作者： Fang yan yan liu Yuan li yan Wang Zicen Deng Meng li Zhenwei Zhu Aohan Zhou Ting li Jingyi Qiu Gaoping Cao Shaobo Huang Biyan Wang Hao Zhang School of Chemistry and Biological Engineering University of Science and TechnologyBeijing 100083China Research Institute of Chemical Defense Beijing 100191China College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina National Base for International Science&Technology Cooperation School of ChemistryXiangtan UniversityXiangtan 411105HunanChina Materials and Manufacturing Department Beijing University of TechnologyBeijing 100124China

To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising *** particular,because of the anisotropy of graphite,hybrid anode formed by graphite/li metal has low transport kinetics and is easy to causes the growth of lithium dendrites and accumulation of dead li,which seriously affects the cycle life of batteries and even causes safety ***,by comparing graphite with two types of hard carbon,it was found that hybrid anode formed by hard carbon and lithium metal,possessing more disordered mesoporous structure and lithophilic groups,presents better *** indicate that the mesoporous structure provides abundant active site and storage space for dead *** the synergistic effect of this structure and lithophilic functional groups(–COOH),the reversibility of hard carbon/lithium metal hybrid anode is maintained,promoting uniform deposition of lithium metal and alleviating formation of lithium *** hybrid anode maintains a 99.5%Coulombic efficiency(CE)after 260 cycles at a specific capacity of 500 m Ah/*** work provides new insights into the hybrid anodes formed by carbon-based materials and lithium metal with high specific energy and fast charging ability.

关键词： Hard carbon/li metal hybrid anode Mesoporous structure Surface oxygen functional group Fast charging lithium batteries

SCAB1 coordinates sequential Ca^(2+) and ABA signals during osmotic stress induced stomatal closure in Arabidopsis

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Science China(life Sciences) 2024年第1期67卷 1-18页

作者： Tianren Zhang li Bai yan Guo State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China

Hyperosmotic stress caused by drought is a detrimental threat to plant growth and agricultural productivity due to limited water *** are gateways of transpiration and gas exchange,the swift adjustment of stomatal aperture has a strong influence on plant drought *** intensive investigations of stomatal closure during drought stress in past decades,little is known about how sequential signals are integrated during complete ***,we discovered that the rapid Ca^(2+) signaling and subsequent abscisic acid(ABA)signaling contribute to the kinetics of both F-actin reorganizations and stomatal closure in Arabidopsis thaliana,while STOMATAL CLOSURE-RELATED ACTIN BINDING PROTEIN1(SCAB1)is the molecular switch for this entire *** the early stage of osmotic shock responses,swift elevated calcium signaling promotes SCAB1 phosphorylation through calcium sensors CALCIUM DEPENDENT PROTEIN KINASE3(CPK3)and *** phosphorylation restrained the microfilament binding affinity of SCAB1,which bring about the Factin disassembly and stomatal closure *** the osmotic stress signal continued,both the kinase activity of CPK3 and the phosphorylation level of SCAB1 attenuated *** further found that ABA signaling is indispensable for these attenuations,which presumably contributed to the actin filament reassembly process as well as completion of stomatal ***,the dynamic changes of SCAB1 phosphorylation status are crucial for the kinetics of stomatal *** together,our results support a model in which SCAB1 works as a molecular switch,and directs the microfilament rearrangement through integrating the sequentially generated Ca^(2+) and ABA signals during osmotic stress induced stomatal closure.

关键词： calcium signal ABA stomatal movement microfilaments kinase

Enhancing Image Description Generation through Deep Reinforcement Learning:Fusing Multiple Visual Features and Reward Mechanisms

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Computers, Materials & Continua 2024年第2期78卷 2469-2489页

作者： yan li Qiyuan Wang Kaidi Jia School of Cyber Security Gansu University of Political Science and LawLanzhou730070China

Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually *** study presents an innovative approach employing deep reinforcement learning to enhance the accuracy of natural language descriptions of *** method focuses on refining the reward function in deep reinforcement learning,facilitating the generation of precise descriptions by aligning visual and textual features more *** approach comprises three key ***,it utilizes Residual Network 101(ResNet-101)and Faster Region-based Convolutional Neural Network(Faster R-CNN)to extract average and local image features,respectively,followed by the implementation of a dual attention mechanism for intricate feature ***,the Transformer model is engaged to derive contextual semantic features from textual ***,the generation of descriptive text is executed through a two-layer long short-term memory network(LSTM),directed by the value and reward *** with the image description method that relies on deep learning,the score of Bilingual Evaluation Understudy(BLEU-1)is 0.762,which is 1.6%higher,and the score of BLEU-4 is ***-based Image Description Evaluation(CIDEr)scored 0.998,Recall-Oriented Understudy for Gisting Evaluation(ROUGE)scored 0.552,the latter improved by 0.36%.These results not only attest to the viability of our approach but also highlight its superiority in the realm of image *** research can explore the integration of our method with other artificial intelligence(AI)domains,such as emotional AI,to create more nuanced and context-aware systems.

关键词： Image description deep reinforcement learning attention mechanism

Low-temperature graphitization of lignin via Co-assisted electrolysis in molten salt

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Green Energy & Environment 2024年第9期9卷 1449-1458页

作者： Shijie li Wei-li Song Xue Han Qingqing Cui yan-li Zhu Shuqiang Jiao Institute of Advanced Structure Technology Beijing Institute of Technology State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

The ever-growing energy demand and environmental issues have stimulated the development of sustainable energy ***,an efficient and environmentally friendly electrochemical transformation technology was proposed to prepare highly graphitized carbon materials from an abundant natural resource-lignin （LG）.The preparation process mainly includes pyrolytic carbonization of raw LG material and electrochemical conversion of amorphous carbon ***,with the assistance of Co catalyst,the graphitization degree of the products was significantly improved,in which the mechanism was the removal of heteroatoms in LG and the rearrangement of carbon atoms into graphite ***,tunable microstructures （nanoflakes） under catalytic effects could also be observed by controlling the electrolytic *** with the products CN1 （without catalyst） and CN5 （with 10%catalyst）,the specific surface area are 158.957 and202.246 m2g-1,*** used as the electrode material for lithium-ion batteries,CN5 delivered a competitive specific capacity of～350 m Ah g-1（0.5 C） compared with commercial *** strategy proposed in this work provides an effective way to extract value-added graphite materials from lignin and can be extended to the graphitization conversion of any other amorphous carbon precursor materials.

关键词： lignin Graphitic carbon Electrochemical conversion lithium-ion batteries

Dynamic Response Impact of Vehicle Braking on Simply Supported Beam Bridges with Corrugated Steel Webs Based on Vehicle-Bridge Coupled Vibration Analysis

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3467-3493页

作者： yan Wang Siwen li Na Wei School of Civil Engineering Zhengzhou UniversityZhengzhou450001China

A novel approach for analyzing coupled vibrations between vehicles and bridges is presented,taking into account spatiotemporal effects and mechanical phenomena resulting fromvehicle *** modeling and solution of bridge vibrations induced by vehicle deceleration are realized using this *** method’s validity and reliability are substantiated through numerical examples.A simply supported beam bridge with a corrugated steel web is taken as an example and the effects of parameters such as the initial vehicle speed,braking acceleration,braking location,and road surface roughness on the mid-span displacement and impact factor of the bridge are *** results show that vehicle braking significantly amplifies mid-span displacement and impact factor responses in comparison to uniform vehicular motion across the ***,the influence of wheelto-bridge friction forces is of particular significance and cannot be *** the vehicle initiates braking near the middle of the span,both the mid-span displacement and impact factor of the bridge exhibit substantial increases,further escalating with higher braking *** favorable road surface conditions,the midspan displacement and the impact factor during vehicle braking may exceed the design values stipulated by *** is important to note that road surface roughness exerts a more pronounced effect on the impact factor of the bridge in comparison to the effects of vehicle braking.

关键词： Corrugated steel web girder bridges simply supported beam bridges vehicle-bridge coupled vibration braking impact factor

Comprehensive DNA barcode reference library and optimization of genetic divergence threshold facilitate the exploration of species diversity of green lacewings (Neuroptera: Chrysopidae)

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Insect Science 2024年第2期31卷 613-632页

作者： yan Lai Kaiyu li Xingyue liu Deparment of Entomology Cllege of Plant ProtectionChina Agricultural UniversityBejingChina College of Bioogical Sciencs China Agricultural UniversityBeijingChina

Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory ***,the taxonomy of Chrysopidae lacks a comprehensive revision,which impedes the exploration of species diversity as well as the selection and the conservation of green lacewings as biocontrol *** have established a DNA barcode reference library of the Chinese green lacewings based on an approximately complete sampling(95.63%)in 25 of the 34 provincial regions in China,comprising 1119 barcodes of 25 genera and 197 species(representing 85%genera and 43.62%species from China).Combining other 1049 high quality green lacewing DNA barcodes,we first inferred the optimal threshold of interspecific genetic divergence(1.87%)for successful species identification in multiple simulated scenarios based on present *** further inferred the threshold of genetic divergence(7.77%)among genera with biocontrol *** inference and performance of the threshold appears to be mainly associated with the completeness of sampling,the proportion of closely related species,and the analytical *** new combinations,Apertochrysa platypa(yang&yang,1991)***.,Apertochrysa shennongana(yang&Wang,1990)***.,Apertochrysa pictifacialis(yang,1988)***.,Apertochrysa helana(yang,1993)***.,Plesiochrysa rosulata(yang&yang,2002)***.,and Signochrysa hainana(yang&yang,1991),are proposed according to integrative species *** library and optimal threshold will effectively facilitate the exploration of species diversity of green *** study also provides a methodological reference in molecular delimitation of other insects.

关键词： Chrysopidae DNA barcode genetic distance optimal threshold species delimitation

Selective core-shell doping enabling high performance 4.6 V-liCoO2

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Journal of Energy Chemistry 2024年第8期95卷 684-693页

作者： Yueming Xia Jianrui Feng Jinhui li yan li Zhengfeng Zhang Xiaoqi Wang Jianli Shao Manling Sui Pengfei yan Beijing Key Laboratory of Microstructure and Property of Solids College of Materials Science & Engineering Beijing University of Technology Petro China Research Institute of Petroleum Exploration & Development State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Constructing robust surface and bulk structure is the prerequisite for realizing high performance high voltage liCoO2（LCO）.Herein,we manage to synthesize a surface Mg-doping and bulk Al-doping coreshell structured LCO,which demonstrates excellent cycling ***-cell shows 94.2% capacity retention after 100 cycles at 3.0-4.6 V（***/li+） cycling,and no capacity decay after 300 cycles for fullcell test（3.0-4.55 V）.Based on comprehensive microanalysis and theoretical calculations,the degradation mechanisms and doping effects are systematically *** the undoped LCO,high voltage cycling induces severe interfacial and bulk degradations,where cracks,stripe defects,fatigue H2 phase,and spinel phase are identified in grain *** the doped LCO,Mg-doped surface shell can suppress the interfacial degradations,which not only stabilizes the surface structure by forming a thin rock-salt layer but also significantly improves the electronic conductivity,thus enabling superior rate *** Al-doping can suppress the lattice "breathing" effect and the detrimental H3 to H1-3 phase transition,which minimizes the internal strain and defects growth,maintaining the layered structure after prolonged *** theoretical calculations,this work deepens our understanding of the doping effects of Mg and Al,which is valuable in guiding the future material design of high voltage LCO.

关键词： Doping effect Electron microscopy Failure mechanism High-voltage liCoO2 lithium-ion battery

Introducing hydroxyl groups to tailor the d-band center of Ir atom through side anchoring for boosted ORR and HER

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Journal of Energy Chemistry 2024年第3期90卷 144-151,I0005页

作者： Qing Lv Meiping li Xiaodong li Xingru yan Zhufeng Hou Changshui Huang Science Center for Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringInstitute of Frontier and Interdisciplinary ScienceShandong UniversityJinan 250100ShandongChina Institute of Chemistry Chinese Academy of ScienceBeijing 100191China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina

Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic ***,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of hydrogen-substituted graphdiyne(HsGDY),and coordinated with OH as an Ir atomic catalyst(Ir_(1)-N-HsGDY).The electron structures,especially the d-band center of Ir atom,are optimized by these specific coordination ***,the as-synthesized Ir_(1)-N-HsGDY exhibits excellent electrocatalytic performances for oxygen reduction and hydrogen evolution reactions in both acidic and alkaline *** from the unique structure of HsGDY,IrN_(2)(OH)_(3) has been developed and demonstrated to act as the active site in these electrochemical *** those indicate the fresh role of the sp-N in graphdiyne in producing a new anchor way and contributing to promote the electrocatalytic activity,showing a new strategy to design novel electrochemical catalysts.

关键词： Oxygen reduction reaction D-band center Graphdiyne Hydroxyl group Electrocatalysis

Influence of rare earth oxides on microstructure and mechanical properties of nickel-based superalloys fabricated by high energy beam processing:A review

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Journal of Rare Earths 2024年第9期42卷 1629-1645,I0001页

作者： lianjie Bi Hua yan Peilei Zhang Haichuan Shi Zhiyuan li Ruidi li School of Materials Science and Engineering Shanghai University of Engineering ScienceShanghai201620China College of Agricultural Science and Engineering Hohai UniversityNanjing211100China Department of Mechanics and Maritime Science Chalmers University of TechnologyGothenburSE41296Sweden State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China

In this paper,the effects of rare earth oxides on the micro structure and mechanical properties of nickelbased superalloys prepared by high-energy beam processing technology were critically *** focus is on the optimal amount of rare earth oxides that can produce ideal *** attention was paid to their main strengthening mechanisms,including solid solution strengthening mainly in the form of solid solution dissolved in the nickel-based alloy and improving the microstructure of the alloy by grain refinement or fine grain strengthening produced by homogenizing the distribution phase.Y_(2)O_(3),La_(2)O_(3) and CeO_(2) rare earth oxides can also improve the fluidity of the alloy molten pool and reduce the segregation of alloying *** advantages can significantly improve the mechanical properties of the ***,this paper outlines the future research directions of rare earth oxides,aiming to expand their application potential.

关键词： Rare earths High energy beam Nickel-based superalloys Microstructure Mechanical properties