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Petroleum Science 2024年第2期21卷 1415-1428页

作者： Miao wang Chao feng School of Business Zhengzhou UniversityZhengzhou450001HenanChina School of Economics and Business Administration Chongqing UniversityChongqing400030China

This paper attempts to explore the decoupling relationship and its drivers between industrial economic increase and energy-related CO_(2) emissions(iCE). Firstly, the decoupling relationship was evaluated by Tapio index. Then, based on the DEA meta-frontier theory framework which taking into account the regional and industrial heterogeneity and index decomposition method, the driving factors of decoupling process were explored mainly from the view of technology and efficiency. The results show that during2000-2019, weak decoupling was the primary state. investment scale expansion was the largest reason hindering decoupling process of industrial increase from iCE. Both energy saving and production technology achieved significant progress, which facilitated the decoupling process. Simultaneously, the energy technology gap and production technology gap among regions have been narrowed, and played a role in promoting decoupling process. On the contrary, both scale economy efficiency and pure tech.ical efficiency have inhibiting effects on decoupling process. The former indicates that the scale economy of China's industry was not conducive to improve energy efficiency and production efficiency, while the latter indicates that resource misallocation problem may exist in both energy market and product market.

关键词： China's industrial sector Decoupling process Meta-frontier DEA index decomposition method Driving factors

A novel method for AFRPs burrs removal:Principle of mechanochemo-induced fiber fracture

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Chinese Journal of Aeronautics 2024年第7期37卷 522-538页

作者： Jie XU Bo Li Pingfa feng Qiang wang feng feng Division of Advanced Manufacturing Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Changhe Aircraft industry(Group)Co.Ltd Jingdezhen 333000China

Burrs generated during the machining of Aramid-Fiber-Reinforced Composites(AFRPs)pose a challenge for the production efficiency of aircraft and helicopter housing *** studies have generally attempted to suppress burrs by referring to delamination suppression *** contrast to stratification,burrs are remediable machining *** such,a mechanochemical method with burrs trimming technological strategy are implemented to effectively combat ***,we clarify the mechanism by which aramid fibers cannot be cut off using analytical and numerical *** addition,the mechanism of fiber fracture with Modified Polyurethane Reactive Polymer(M-PUR),and development of anti-burr devices(thermostatic adhesive sealed generator)are ***,the experimental results show that the reduction rate in burr length.is 87%-91%through the mechanochemical *** method not only opens a new avenue to solve the burr problem of aramid fibers but also builds an interdisciplinary bridge between polymer science and composite machining.

关键词： Mechanochemical method Burrs Orthogonal cutting Aramid fiber-reinforced composites Milling

Derivation of Expanded isospectral-Nonisospectral integrable hierarchies via the Column-vector Loop Algebra

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 778-800页

作者： h.i-feng wang Yu-feng ZhANG School of Science Jimei UniversityXiamen 361021China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

A scheme for generating nonisospectral integrable hierarchies is *** on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral *** follows that the corresponding expanded isospectral and nonisospectral integrable hierarchies are deduced based on a 6 dimensional complex linear space ■.By reducing these integrable hierarchies,we obtain the expanded isospectral and nonisospectral derivative nonlinear Schr?dinger *** using the trace identity,the bihamiltonian structure of these two hierarchies are also ***,some symmetries and conserved quantities of the resulting hierarchy are discussed.

关键词： expanded isospectral-nonisospectral integrable hierarchies column-vector loop algebra bi-hamiltonian structure symmetry

Efficient Monolithic Perovskite/Silicon Tandem Photovoltaics

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Energy & Environmental Materials 2024年第3期7卷 272-285页

作者： Yong wang Yu wang feng Gao Deren Yang State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang University ZJU-hangzhou Global Scientific and Technological innovation Center Zhejiang University Department of Physics Chemistry and Biology (IFM) Linkping University

Tunable bandgaps make halide perovskites promising candidates for developing tandem solar cells (TSCs),a strategy to break the radiative limit of 33.7%for single-junction solar *** perovskites with marketdominant crystalline silicon (c-Si) is particularly attractive; simple estimates based on the bandgap matching indicate that the efficiency limit in such tandem device is as high as 46%.however,state-of-the-art perovskite/c-Si TSCs only achieve an efficiency of～32.5%,implying significant challenges and also rich *** this review,we start with the operating mechanism and efficiency limit of TSCs,followed by systematical discussions on wide-bandgap perovskite front cells,interface selective contacts,and electrical interconnection layer,as well as photon management for highly efficient perovskite/c-Si *** high.ight the challenges in this field and provide our understanding of future research directions toward highly efficient and stable large-scale wide-bandgap perovskite front cells for the commercialization of perovskite/c-Si TSCs.

关键词： 2-terminal electrical interconnection perovskite/silicon tandem photovoltaics photon management wide-bandgap perovskites

Mathematics of multi-agent learning systems at the interface of game theory and artificial intelligence

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Science China(information Sciences) 2024年第6期67卷 445-447页

作者： Long wang feng FU Xingru ChEN Center for Systems and Control College of EngineeringPeking University Center for Multi-Agent Research Institute for Artificial IntelligencePeking University Department of Mathematics Dartmouth College Department of Biomedical Data Science Geisel School of Medicine at Dartmouth School of Science Beijing University of Posts and Telecommunications

Evolutionary game theory (EGT) and artificial intelligence(Ai) are two fields that,at first glance,might seem distinct,but they have notable connections and *** former focuses on the evolution of behaviors (or strategies)in a population,where individuals interact with others and update th.ir strategies based on imitation (or social learning).

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Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

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Acta Mechanica Solida Sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang Shi-Wen Chen Si-he wang Zhen-Yuan Gong Jun feng Gang-feng wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously sh.inks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. however, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with.increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

Ag-doped CNT/hAP nanohybrids in a PLLA bone scaffold show significant antibacterial activity

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Bio-Design and Manufacturing 2024年第2期7卷 105-120页

作者： Cijun Shuai Xiaoxin Shi Kai wang Yulong Gu feng Yang Pei feng State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China College of Mechanical Engineering Xinjiang UniversityUrumqi 830017China

Bacterial infection is a major problem following bone implant ***,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/hAP)bone scaffolds possess enhanced mechanical properties and show good ***,wesynthesizedsilver(Ag)-dopedCNT/hAP(CNT/Ag-hAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the hAP lattice with silver ions(Ag+)using an ion doping tech.ique under hydrothermal ***ﬁcally,the doping process was induced using the special lattice structure of hAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the hAP lattice by doped Ag+as well as the in situ synthesis of Ag-hAP nanoparticles on CNT in a hydrothermal *** result-ing CNT/Ag-hAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-hAP scaffolds that showed sustained antibacterial *** then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-hAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of *** addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,***,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).

关键词： Ag-doped Carbon nanotube/hydroxyapatite(CNT/hAP) Antibacterial properties Bone scaffold

Beam Training and Tracking in mmWave Communication:A Survey

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China Communications 2024年第6期21卷 1-22页

作者： wang Yi Wei Zhiqing feng Zhiyong Yangtze Delta Region institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324003China School of information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Communicating on millimeter wave(mmWave)bands is ushering in a new epoch of mobile communication which provides the availability of 10 Gbps high data rate ***,mmWave links are easily prone to short transmission range communication because of the serious free space path loss and the blockage by *** overcome these challenges,highly directional beams are exploited to achieve robust links by hybrid *** aligning the transmitter and receiver beams,*** training,is vitally important to high data rate ***,it may cause huge overhead which has negative effects on initial access,handover,and ***,the mobility patterns of users are complicated and dynamic,which may cause tracking error and large tracking *** efficient beam tracking method has a positive effect on sustaining robust *** article provides an overview of the beam training and tracking technologies on mmWave bands and reveals the insights for future research.in the 6th Generation(6G)mobile ***,some open research problems are proposed to realize fast,accurate,and robust beam training and *** hope that this survey provides guidelines for the researchers in the area of mmWave communications.

关键词： 6G beam tracking beam training beamforming mmWave

Cloud Microphysical Characteristics of Typhoon Meranti(2016)during its Rapid intensification:Model Validation and SST Sensitivity Experiments

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Journal of Meteorological Research 2024年第3期38卷 542-557页

作者： Rui wang Yihong DUAN Jianing feng Department of Atmospheric and Oceanic Sciences&institute of Atmospheric Sciences Fudan UniversityShanghai200438China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China

Cloud microphysics plays an important role in determining the intensity and precipitation of tropical cyclones(TCs).in this study,a high-resolution numerical simulation by WRF(version 4.2)of Typhoon Meranti(2016)during its rapid intensification(Ri)period was conducted and validated by multi-source observations including Cloud-Sat and Global Precipitation Mission satellite *** snow and ice particles content were found to increase most rapidly compared with other hydrometeors during the Ri *** all hydrometeors continued to *** graupel content only increased in the initial Ri stage,and then decreased afterwards due to precipitation during the Ri *** addition,sea surface temperature(SST)sensitivity experiments showed that,although the intensity of the TC increased with a higher SST,not all hydrometeors *** graupel content continued to increase with the increase in SST,mainly due to the accumulation of more lower-temperature supercooled water vapor at the corresponding *** content of snow decreased with the increase in SST because stronger vertical motion at the corresponding h.ight affected the aggregation of ice crystals.

关键词： tropical cyclone rapid intensification cloud microphysical characteristics sea surface temperature(SST)

Advancing mid-infrared microdisk laser emission with Tm:YAG

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 91-96页

作者： Zhaocong wang h.iqi Li Lei wang Yang Tan feng Chen School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China

Mid-infrared microcavity lasers have important applications in biosensing,mid-infrared spectroscopy,and environmental ***,the low output power of existing mid-infrared microcavity lasers hinders th.ir practical *** drawback is attributed to the insufficient laser gain medium,which limits the development of mid-infrared whispering-gallerymode(WGM)*** address this issue,we have employed ion implantation-enhanced etching to fabricate Tm:YAG thin films as effective gain media for mid-infrared WGM *** Tm:YAG thin film,with a thickness of 2μm,exhibits excellent fluorescence ***,the Tm:YAG thin film is processed using focused ion beam to form microdisks with a diameter of 30μ*** 785 nm laser pumping,the maximum output power of the Tm:YAG microdisk at 2023.1 nm is229μW,with a slope efficiency of 2.9%.This work demonstrates the outstanding potential of Tm:YAG as a mid-infrared laser gain medium,providing a new option for the development of mid-infrared lasers.

关键词： microdisk microlaser ultrathin film