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Journal of Computational Mathematics 2000年第5期18卷 487-512页

作者： han-lin chen,si-long peng (Institute of Mathematics, Chinese Academy of Sciences, Beijing 100080, China) 中科院数学所北京 100080

In solving integral equations with logarithmic kernel which arises from the boundary integral equation reformulation of some boundary value problems for the two dimensional Helmholtz equation, we combine the Galerkin method with Beylkin's ([2]) approach, series of dense and nonsymmetric matrices may appear if we use traditional method. By appealing the so-called periodic quasi-wavelet (PQW in abbr.) ([5]), some of theme matrices become diagonal, therefore we can the a algorithm with only O(K(m)2) arithmetic operations where m is the highest level. The Galerkin approximation has a polynomial rate of convergence.

关键词： Periodic Quasi-Wavelet Integral equation Multiscale.

Two-Dimensional Materials for Highly Efficient and Stable Perovskite Solar Cells

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Nano-Micro Letters 2024年第10期16卷 176-212页

作者： Xiangqian Shen Xuesong lin Yong peng Yiqiang Zhang Fei long Qifeng han Yanbo Wang Liyuan han State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People's Republic of China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physical Science and TechnologyXinjiang UniversityUrumqi 830046People's Republic of China Special Division of Environmental and Energy Science College of Arts and SciencesKomaba Organization for Educational ExcellenceUniversity of TokyoTokyo 153-8902Japan State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People's Republic of China College of Chemistry Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001People's Republic of China Guangxi Key Laboratory of Optical and Electronic Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004People's Republic of China

Perovskite solar cells(PSCs)offer low costs and high power conversion ***,the lack of long-term stability,primarily stemming from the interfacial defects and the sus-ceptible metal electrodes,hinders their practical *** the past few years,two-dimensional(2D)materials(e.g.,graphene and its derivatives,transitional metal dichalcogenides,MXenes,and black phosphorus)have been identified as a promising solution to solving these problems because of their dangling bond-free surfaces,layer-dependent electronic band structures,tunable functional groups,and inherent ***,recent progress of 2D material toward efficient and stable PSCs is summarized,including its role as both interface materials and *** discuss their beneficial effects on perovskite growth,energy level alignment,defect passivation,as well as blocking external *** particular,the unique properties of 2D materials to form van der Waals heterojunction at the bottom interface are ***,perspectives on the further development of PSCs using 2D materials are provided,such as designing high-quality van der Waals heterojunction,enhancing the uniformity and coverage of 2D nanosheets,and developing new 2D materials-based electrodes.

关键词： Perovskite solar cells Two-dimensional materials Interface engineering Van der Waals heterojunction Electrodes

Epitaxial quasi-2D/3D hybrid perovskite heterojunctions for photodetector with enhanced detectivity and stability

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Nano Research 2024年第7期17卷 6594-6602页

作者： Yifu chen lin Zhang Xinxin peng Weiran Qin Shiqing Li Yingwei Wang Zhihui chen si Xiao Bin Yang Biao Liu Junliang Yang han Huang Yun lin Jun He Liming Ding Yongbo Yuan Hunan Key Laboratory of Super Microstructure and Ultrafast Process School of PhysicsCentral South UniversityChangsha 410083China Hunan Key Laboratory of Nanophotonics and Devices School of PhysicsCentral South UniversityChangsha 410083China College of Materials Science and Engineering Hunan UniversityChangsha 410082China Department of Photoelectric Information School of PhysicsCentral South UniversityChangsha 410083China Center for Excellence in Nanoscience Key Laboratory of Nanosystem and Hierarchical FabricationNational Center for Nanoscience and TechnologyChinese Academy of ScienceBeijing 100190China

Although numerous metal halide perovskite materials have been investigated in the field of optoelectronic,the development of perovskite heterojunctions with exotic structures is still ***,we report the epitaxial growth of quasi-two-dimensional(Q-2D)perovskites on methylammonium lead iodide(MAPbI_(3))single crystals to form perovskite heterojunctions with interfacial *** MAPbI_(3)adjacent to epitaxial Q-2D perovskite shows blue shifted photoluminescence with shortened lifetime,which becomes significant with the reduced layer number of the Q-2D *** findings suggest the presence of an interfacial strain gradient leading to enhanced photocarrier ***,compared to the MAPbI_(3)single crystal detector,the BA_(2)MAPb_(2)I_(7)/MAPbI_(3)(BA:n-butylamine)heterojunction-based photodetector demonstrates a bandpass detecting property and exhibits 5 times enhanced external quantum efficiency and 83 times enhanced specific detectivity(D*=3.26×10^(11)Jones).Remarkably,the unencapsulated BA_(2)MAPb_(2)I_(7)/MAPbI_(3)heterojunction is stable in ambient condition for>300 *** Q-2D/3D heterojunction shows suppressed ion inter-diffusion due to the presence of Q-2D phase.

关键词： epitaxial growth interfacial strain quasi-two-dimensional/three-dimensional(Q-2D/3D)heterojunctions ion inter-diffusion

Lithium polysulfide solvation and speciation in the aprotic lithium-sulfur batteries

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Particuology 2024年第6期89卷 238-245页

作者： Jinhao Zhang Qingshan Fu peng Li Ruibo linghu Xiaozhong Fan Haibin lin Juncao Bian Songbai han Gengzhi Sun long Kong Frontiers Science Center for Flexible Electronics and Xi’an Institute of Flexible Electronics Northwestern Polytechnical UniversityXi’an710129China China Automotive Innovation Corporation Nanjing211100China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen518055China Institute of Advanced Materials Nanjing Tech UniversityNanjing211816China

Fingerprinting sulfur speciation in aprotic electrolytes is a key to understand fundamental chemistry and design well-performing lithium–sulfur(Li–S)*** polysulfide(LiPS)dissolution and deposition in ether-based electrolytes during redox reactions have been probed and established by spectroscopy and ***,detailed LiPS structure and solvation properties influenced by conventional and newly developed electrolytes remain elusive,which exert fundamental challenges and practical difficulties in decoupling battery performance from electrolyte *** perspective aims to provide timely information to uncover underlying mechanisms that rein in sulfur speciation by considering the charge density of LiPSs and the coordination strength of solvents/*** discussion starts with unlocking the baseline electrolyte formulation to investigate its role in LiPS formation and *** that,the term coordination strength is used instead of donor number and dielectric constant to describe interactions between solvents and LiPSs and to reveal LiPS structure *** work is expected to encourage the discovery of new electrolyte working mechanisms to develop energy-dense and power-intensive Li–S batteries.

关键词： Sulfur speciation Redox kinetics Coordination strength Solvation chemistry Lithium-sulfur batteries

Preparation and interaction mechanism analysis of single‑chain fragment variables against phenylethanolamine A

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Animal Diseases 2024年第2期4卷 127-137页

作者： long Li Ren Hou Huaming Li Shiyun han Jixiang Liang Yu si Dapeng peng State Key Laboratory of Agricultural Microbiology National Reference Laboratory of Veterinary Drug Residues(HZAU)and MOA Key Laboratory for Detection of Veterinary Drug ResiduesHuazhong Agricultural UniversityWuhan 430070PR China Key Laboratory of Preventive Veterinary Medicine in Hubei Province The Cooperative Innovation Center for Sustainable Pig ProductionWuhan 430070China Hubei Topgene Biotechnology Co. Ltd.Wuhan BranchWuhanHubei 430070China Shenzhen Institute of Nutrition and Health Huazhong Agricultural UniversityShenzhenGuangdong 518000China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong 518000China

This is the first report on the screening,expression,and recognition mechanism analysis of single-chain fragment variable(scFv)against phenylethanolamine A(PEAA),a newly emergedβ-adrenergic agonist illegally used as a feed additive for growth *** PEAA-specific scFv scFv,called scFv-32,was screened from hybridoma cell lines by phage display and was found to be optimally expressed in the *** *** ic-ELISA results revealed an IC_(50)value of 10.34μg/L for scFv-32 and no cross-reactivity with otherβ-adrenergic *** modeling and molecular docking revealed the key binding sites VAL178,TYP228,and *** hydrogen bond,two pisigma bonds,and one pi-pi bond maintain the formation of the antibody‒drug *** scanning mutagenesis of the three predicted key binding sites showed that the mutants completely lost their recognition activity,which confirmed the accuracy of the theoretical *** results are valuable for the preparation of scFvs and the analysis of the molecular recognition mechanism of antigen-antibodies.

关键词： Phenylethanolamine A ScFv Recognition mechanism Homology modeling Molecular docking

Jetting of a near-wall cavitation bubble induced by another tandem bubble

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Journal of Hydrodynamics 2024年第3期36卷 444-456页

作者： Hui han Jing-zhu Wang Jian-lin Huang peng-bo Bai Yong-gang chen Yi-wei Wang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Guangdong Aerospace Research Academy Guangzhou511458China School of Future Technology University of Chinese Academy of SciencesBeijing100049China Jianghuai Advance Technology Center Hefei230088China

Double bubbles near a rigid wall surface collapse to produce a significant jet impact,with potential applications in surface cleaning and ultrasonic ***,the dynamic behaviors of near-wall bubbles remain *** this study,we investigate the jetting of a near-wall bubble induced by another tandem *** define two dimensionless standoff distances,γ_(1),γ_(2),to represent the distances from the center of the near-wall bubble to the rigid wall and the center of controlling bubble to the center of the near-wall bubble,*** observations reveal three distinct jetting regimes for the near-wall bubble:transferred jetting,double jetting,and directed *** further investigate the jetting mechanism,numerical simulations are conducted using the compressibleInterFoam solver in the open-source framework of OpenFOAM.A detailed analysis shows that the transferred jet flow is caused by the pinch-off resulting from the axial contraction velocity at the lower end of the near-wall bubble being greater than the vertical contraction velocity,leading to a maximum jet velocity of 682.58 m/*** the case of double jetting,intense stretching between the controlling bubble and the wall leads to a pinch-off and a double jetting with a maximum velocity of 1096.29 m/*** directed jet flow is caused by the downward movement of the high-pressure region generated by the premature collapse of the controlling bubble,with the maximum jet velocity reaching 444.62 m/s.

关键词： Jetting of near-wall bubble controlling bubble impact velocity

Feasibility Study on Recovering Human-Occupied Vehicle with An Offshore Crane

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China Ocean Engineering 2024年第4期38卷 648-662页

作者： han Ming-yue XIE peng XIAN Hao-yi ZHONG Xin-xin chen Sheng-lin SUN Tie-rui SUN Feng-lei School of Ocean Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-sen University) Ministry of EducationZhuhai 519082China Guangzhou Marine Engineering Corporation Guangzhou 510250China

Launching and recovering human-occupied vehicles(HOVs)has always been a challenging *** current recovery process requires staff to manually complete the tethering task,which is inefficient and endangers the lives of *** paper suggests moving the recovery position from the surface to underwater at approximately half the wavelength of the water depth(30−50 m underwater),where the HOV experiences less environmental *** ROV equipped with a ultra-short baseline beacon(USBL)and a manipulator was used to complete the tethering ***,a shackle customized to the shape of the manipulator’s gripper is fitted to the end of the cable to simplify the tethering *** investigate the dynamic response of recovering the HOV using this suggested method,a comprehensive numerical model is developed in this *** effects of wind,surface waves,ocean currents,and nonlinear interaction between the installation vessel and the HOV are quantitatively *** results show that the proposed recovery method can reduce the motion amplitude of the HOV and that the wave has the greatest influence on the dynamic response of the HOV during the recovery *** model provides better insight into the proposed HOV recovery method and confirms the effectiveness of the heave compensation *** proposed approach aims to enhance safety and operational efficiency by reducing direct human involvement in the recovery process and mitigating potential *** finding holds particular significance,especially in environmentally sensitive areas,where reducing the impact on the surrounding ecosystem is crucial.

关键词： human-occupied vehicle recovery dynamic response active heave compensation

Ni-Catalyzed Enantioselective Difunctionalization of Alkynes to Azepine Derivatives Bearing a Quaternary Center and an Unprotected Imine

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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： Jian long Zhiwu Lu Xiao-lin Li peng Xue Wen-Bo Liu Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

Enhancement of deltaful two-pion exchange nuclear forces

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Communications in Theoretical Physics 2024年第9期76卷 48-54页

作者： Haiming chen Rui peng Songlin Lyu Bingwei long College of Physics Sichuan UniversityChengduSichuan 610065China School of Physics Peking UniversityBeijing 100871China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000Guangdong ProvinceChina

The role of the delta isobar degrees of freedom in nucleon–nucleon scattering is *** attempt to understand why the dimensionally regularized two-pion exchanges with the explicit delta isobar is much stronger than the ones with spectral function *** the cutoff value of spectral function regularization is varied,the isoscalar central component exhibits a rather large cut-off *** reveals a surprisingly large numerical factor of the deltaful two-pion exchange *** power counting is adjusted accordingly and we discuss the results and how to improve upon this finding.

关键词： chiral nuclear force delta resonance power counting

Unmanned autonomous air-to-air refueling intelligent docking technology

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Chinese Journal of Aeronautics 2024年第5期37卷 1-5页

作者： peng lin Yakun HE Yuanze chen Chinese Aeronautical Establishment Beijing 100029China

Unmanned autonomous Air-to-Air Refueling(AAR)capability is the key guarantee to support the distant-field,high-intensity and durable operations of the penetration counterair combat *** the future,the long-range unmanned reconnaissance and attack platform can reach the maximum flight range requirement through *** present,large transport aircraft platforms in China are still equipped with probe-and-drogue systems,and the refueling mode is gradually changing from manned to unmanned autonomous *** docking process is the riskiest and most important part,and there are strict safety,precision,and efficiency requirements for refueling operation,especially during close-distance docking and formation maintenance *** this paper,five issues that need to be solved to achieve autonomous AAR docking are *** this basis,five key technology development needs are proposed to solve these engineering ***,some prospects are given.

关键词： Air-to-air refueling Probe-and-drogue Unmanned aerial vehicles Docking Perception Collaborative control