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Chinese Journal of Aeronautics 2025年第1期38卷 271-285页

作者： Tao zhang Xuhui zhang Luoyu RAO Chongguang SHI Chengxiang ZHU Yancheng YOU School of Aerospace Engineering Xiamen UniversityXiamen 361005China China Academy of Aerospace Science and Innovation Beijing 100176China

The primary Mach Reflection(MR)and pressure/heating loads on V-shaped Blunt Leading Edges(VBLEs)with variable elliptic cross-sections and conic crotches are theoretically investigated in this *** simplified continuity method is used to forecast the shock *** theoretical predictions and the numerical simulations for the Mach stem and the triple point as well as the curved shock accord *** on the theoretical model,an analysis of the impact of the axial ratio a/b of the cross-sectional shape and the eccentricity e of the crotch sweep path on shock structures is carried *** shock configurations obtained from the theoretical model enable the derivation of the transition boundaries between the primary MR and the same family Regular Reflection(sRR).It is found that the increase of a/b and e can both facilitate the primary MR to sRR *** resulting transition and the corresponding generation of the wall pressure and heat flux are then *** results indicate that higher values of the ratio a/b can significantly reduce the wall pressure and heating loads by inducing the primary MR to sRR ***,the increase in the eccentricity e results in increased loads,despite causing the same transition.

关键词： Aerodynamics Hypersonic flow Shock waves Heat flux V-shaped blunt leading edges

Co_(0.5)Zn_(0.5)Fe_(2)O_(4)modified residual carbon as an excellent microwave absorber

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 534-545页

作者： Yuanchun zhang Dacheng Ma Xingzhao zhang Chuanlei Zhu Shengtao Gao School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China

Microwave absorbers have great potential for military and civil ***,Co_(0.5Z)n_(0.5)Fe_(2)O_(4)/residual carbon(CZFO/RC)composites have been successfully prepared using a hydrothermal *** was derived from coal gasification fine slag(CGFS)via pickling,which removes inorganic *** test means have been used to study the chemical composition,crys-tal structure,and micromorphology of the CZFO/RC composites,as well as their electromagnetic parameters and microwave absorption(MA)*** CZFO/RC composites exhibit excellent MA performance owing to their dielectric and magnetic *** the thickness of CZFO/RC-2(FeCl_(3)·6H_(2)O of 0.007 mol,ZnCl_(2)of 0.00175 mol,and CoCl_(2)·6H_(2)O of 0.00175 mol)is 1.20 mm,the minimum reflection loss(RL_(min))is-56.24 dB,whereas at a thickness of 3.00 mm and 6.34 GHz,RL_(min) is-45.96 dB and the maximum effective ab-sorption bandwidth is 1.83 GHz(5.53-7.36 GHz).Dielectric loss includes interface and dipole polarizations,while magnetic loss includes current and remnant magnetic ***/RC-2 exhibits high impedance matching,allowing microwave to enter the *** com-puter simulation technology confirms that CZFO/RC-2 considerably decreases the radar *** study can be used to promote the use of CGFS as electromagnetic wave(EMW)-absorbing materials.

关键词： cobalt-zinc ferrite residual carbon microwave absorption coal gasification fine slag coal-based solid waste

The rise and potential of large language model based agents:a survey

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Science China(Information Sciences) 2025年第2期68卷 15-58页

作者： Zhiheng XI Wenxiang CHEN Xin GUO Wei HE Yiwen DING Boyang HONG Ming zhang Junzhe WANG Senjie JIN Enyu ZHOU Rui ZHENG Xiaoran FAN Xiao WANG Limao XIONG Yuhao ZHOU Weiran WANG Changhao JIANG Yicheng ZOU Xiangyang LIU zhangyue YIN Shihan DOU Rongxiang WENG Wenjuan QIN Yongyan ZHENG Xipeng QIU Xuanjing HUANG Qi zhang Tao gui School of Computer Science Fudan University College of Foreign Languages and Literature Fudan University Meituan Institute of Modern Languages and Linguistics Fudan University

For a long time, researchers have sought artificial intelligence(AI) that matches or exceeds human *** agents, which are artificial entities capable of sensing the environment, making decisions, and taking actions, are seen as a means to achieve this goal. Extensive efforts have been made to develop AI agents, with a primary focus on refining algorithms or training strategies to enhance specific skills or particular task performance. The field, however, lacks a sufficiently general and powerful model to serve as a foundation for building general agents adaptable to diverse scenarios. With their versatile capabilities, large language models(LLMs) pave a promising path for the development of general AI agents, and substantial progress has been made in the realm of LLM-based agents. In this article, we conduct a comprehensive survey on LLM-based agents, covering their construction frameworks, application scenarios, and the exploration of societies built upon LLM-based agents. We also conclude some potential future directions and open problems in this flourishing field.

关键词： natural language processing large language models LLM-based agents AI agents agent society

Enantioselective copper-catalyzed dearomative borylative cyclization of indoles and mechanistic insights

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Science China Chemistry 2025年第2期68卷 670-678页

作者： Yanfei Li Xuetao Li Zheng zhang Yiliang zhang Xiuping Yuan Jianjun Yin Simin Wang Wei Guan Qian zhang Tao Xiong Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Functional Material Chemistry Department of ChemistryNortheast Normal UniversityChangchun 130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025China

Alicyclic nitrogen heterocycles,such as enantioenriched polycyclic fused[1,2-a]indoline derivatives,are widespread in natural products,agrochemicals and pharmaceutical *** methods predominantly rely on the recent emerging Heck-type catalytic asymmetric dearomatization(CADA)protocol,wherein noble palladium catalysts commonly necessitate the form arylPd species-triggered these *** contrast,a more sustainable base metal catalysis paradigm through alkyl metal species disrupting the aromaticity,that is,the utilization of challenging asymmetric Csp3–Csp3 bond formation entry to such important chiral densely functionalized polycyclic molecular scaffolds,remains an elusive ***,we report the first copper-catalyzed dearomative borylative cyclization of indoles under mild reaction conditions,affording an array of valuable Bpin-containing pyrrolo-fused[1,2-a]indolines bearing four consecutive stereogenic centers with excellent enantioand *** synthetic potential was documented via an array of useful *** functional theory(DFT)calculation studies elucidated the origin of the chemo-,regio-,enantio-and diastereoselectivities of this conversion.

关键词： copper catalysis dearomatization borylative cyclization indoles DFT calculations

Control of Corner Separation for a Linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： zhang Peng LI Yonghong CHENG Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of ChinaTianjin 300300China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： corner separation compressor cascade slanting riblets additional losses vortex generator

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China(Life Sciences) 2025年第1期68卷 272-283页

作者： Yuwei Hua Yizhi zhang Zhenming Guo Shan Bian Yong zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level,limiting their applications in biological ***,we introduce ImSpiRE,an image feature-aided spatial resolution enhancement method for in situ capturing spatial *** the information stored in histological images,ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution,together with extending the gene expression profiles into unmeasured *** to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains,signaling communication patterns,and spatiotemporal characterization.

关键词： spatial transcriptome histological images spatial resolution enhancement

New results on finite-time stability and instability theorems for stochastic nonlinear time-varying systems

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Science China(Information Sciences) 2025年第2期68卷 186-199页

作者： Weihai zhang Liqiang YAO College of Electrical Engineering and Automation Shandong University of Science and Technology School of Mathematics and Information Science Yantai University

This paper studies finite-time stability and instability theorems in the probability sense for stochastic nonlinear timevarying systems. Firstly, a new sufficient condition is proposed to guarantee that the considered system has a global ***, we propose new finite-time stability and instability criteria that relax the constraints on LV(the infinitesimal operator of Lyapunov function V) by the uniformly asymptotically stable function. On the one hand, these obtained results make up for the shortcomings of the existing results. On the other hand, the new finite-time stability theorems can be viewed as natural extensions of the existing results and also allow LV to be indefinite(negative or positive) rather than just only allow LV < ***, some simulation examples verify the validity of the theoretical results.

关键词： stochastic nonlinear systems finite-time stability finite-timeinstability uniformly asymptotically stable function

Bilevel Optimal Scheduling of Island Integrated Energy System Considering Multifactor Pricing

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Energy Engineering 2025年第1期122卷 349-378页

作者： Xin zhang Mingming Yao Daiwen He Jihong zhang Peihong Yang Xiaoming zhang School of Automation and Electrical Engineering Inner Mongolia University of Science and TechnologyBaotou014010China

In this paper,a bilevel optimization model of an integrated energy operator(IEO)–load aggregator(LA)is constructed to address the coordinate optimization challenge of multiple stakeholder island integrated energy system(IIES).The upper level represents the integrated energy operator,and the lower level is the electricity-heatgas load *** to the benefit conflict between the upper and lower levels of the IIES,a dynamic pricing mechanism for coordinating the interests of the upper and lower levels is proposed,combined with factors such as the carbon emissions of the IIES,as well as the lower load interruption *** price of selling energy can be dynamically adjusted to the lower LA in the mechanism,according to the information on carbon emissions and load interruption *** benefits and win-win situations are achieved between the upper and lower ***,CPLEX is used to iteratively solve the bilevel optimization *** optimal solution is selected according to the joint optimal discrimination *** results indicate that the sourceload coordinate operation can reduce the upper and lower operation *** the proposed pricingmechanism,the carbon emissions and load interruption power of IEO-LA are reduced by 9.78%and 70.19%,respectively,and the capture power of the carbon capture equipment is improved by 36.24%.The validity of the proposed model and method is verified.

关键词： Bilevel optimal scheduling load aggregator integrated energy operator carbon emission dynamic pricing mechanism

Adaptive VDI Session Placement via User Logoff Prediction

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Machine Intelligence Research 2025年第1期22卷 189-200页

作者： Wenping Fan Puhui Meng Yu Tian Min-Ling zhang Yao zhang School of Computer Science and Engineering Southeast UniversityNanjing210096China VMware Information Technology(China)Limited Beijing100190China Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of EducationNanjing210096China

After the global pandemic,DaaS(desktop as a service)has become the first choice of many companies’remote working *** the desktops are usually deployed in the public cloud when using DaaS,customers are more cost-sensitive which boosts the requirement of proactive power *** researches in this area focus on virtual desktop infrastructure(VDI)session logon behavior modeling,but for the remote desktop service host(RDSH)-shared desktop pools,logoff optimization is also *** systems place sessions by round-robin or in a pre-defined order without considering their logoff ***,these approaches usually suffer from the situation that few left sessions prevent RDSH servers from being powered-off which introduces cost *** this paper,we propose session placement via adaptive user logoff prediction(SODA),an innovative compound model towards proactive RDSH session ***,an ensemble machine learning model that can predict session logoff time is combined with a statistical session placement bucket model to place RDSH sessions with similar logoff time in a more centralized manner on RDSH ***,the infrastructure cost-saving can be improved by reducing the resource waste introduced by those RDSH hosts with very few hanging sessions left for a long *** on real RDSH pool data demonstrate the effectiveness of the proposed proactive session placement approach against existing static placement techniques.

关键词： Virtual desktop infrastructure(VDI)resource management remote desktop service logoff prediction adaptive modeling session placement

Chemical characteristics and sources apportionment of volatile organic compounds in the primary urban area of Shijiazhuang,North China Plain

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Journal of Environmental Sciences 2025年第3期149卷 465-475页

作者： Xiao zhang Junfeng Wang Jiangwei Zhao Junliang He Yali Lei Kai Meng RuiWei Xue zhang Miaomiao zhang Shuangying Ni Eleonora Aruffo College of geographical sciences and Environment Shijiazhuang UniversityShijiazhuang 050035China 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 and TechnologyNanjing 210044China Hebei Province Ecology Environmental Monitoring Center Shijiazhuang 050037China Key Lab of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Hebei Provincial Institute of Meteorological Sciences Shijiazhuang 050021China Key Laboratory of Meteorology and Ecological Environment of Hebei Province Shijiazhuang 050021China Hebei Provincial Academy of Ecological Environmental Science Shijiazhuang 050037China Department of Advanced Technologies in Medicine&Dentistry University“G.d’Annunzio”of Chieti-PescaraChieti 66100Italy Center for Advanced Studies and Technology-CAST Chieti 66100Italy

VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric *** to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and ***,the PMF(positive matrix factorization)method was utilized to identify the VOCs *** indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive *** sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,***,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels.

关键词： Volatile organic compounds Pollution characteristics Ozone formation potential OH radical loss rate Source apportionment