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Special issue:Catenary optics and catenary electromagnetics

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Opto-Electronic Advances 2024年第5期7卷 1-4页

作者： Qian sun Minghui hong Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKkeM) Xiamen 361005China

As a natural mathematical form,a catenary is the curve that a hanging chain or cable adopts under its own weight when supported at its ends in a homogeneous gravitational *** unique shape arises from the balance of forces acting on each segment of the chain,resulting in a curve described by hyperbolic cosine *** functions play pivotal roles in describing the electromagnetic field,intensity distribution,and dispersion of structured light on the sub-wavelength scale^(1).

关键词： functions. field. optics

New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

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Chinese Journal of Natural Medicines 2024年第2期22卷 161-170页

作者： sun Zeshi LIN Shan WU Zhi-Li DONG hong-Yuan XU Xi-ke LI Hui-Liang WANG Jinxin School of Pharmacy Second Military Medical UniversityShanghai 200433China State key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China

Our continued works on the chemical constituents of Ginkgo biloba(***)leaves has led to the isolation of two novel phenylbutenoids(1,2),along with five previously unidentified terpene glycosides(3−7).Among them,compounds 1 and 2 represent unique(Z)-phenylbutenoids,3−6 are megastigmane glycosides,and 7 is identified as a rare bilobanone glycoside(Fig.1).This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from *** chemical structures of these compounds were elucidated through extensive spectroscopic analysis,including HR-ESI-MS and various 1D and 2D NMR ***,the absolute configurations of these molecules were determined using Mosher’s method,ECD experiments,and Cu-KαX-ray crystallographic analyses.

关键词： Ginkgo biloba Phenylbutenoid Megastigmane glycoside Bilobanone glycoside

Deep Reinforcement Learning-Based Task Offloading and Service Migrating Policies in Service Caching-Assisted Mobile Edge Computing

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China Communications 2024年第4期21卷 88-103页

作者： ke hongchang Wang Hui sun hongbin Halvin Yang School of Computer Technology and Engineering Changchun Institute of TechnologyChangchun 130012China College of Computer Science and Engineering Changchun University of TechnologyChangchun 130012China Department of Electronic and Electrical Engineering University College LondonLondonUK

Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and *** to the homogeneity of request tasks from one MWE during a longterm time period,it is vital to predeploy the particular service cachings required by the request tasks at the MEC *** this paper,we model a service caching-assisted MEC framework that takes into account the constraint on the number of service cachings hosted by each edge server and the migration of request tasks from the current edge server to another edge server with service caching required by ***,we propose a multiagent deep reinforcement learning-based computation offloading and task migrating decision-making scheme(MBOMS)to minimize the long-term average weighted *** proposed MBOMS can learn the near-optimal offloading and migrating decision-making policy by centralized training and decentralized *** and comprehensive simulation results reveal that our proposed MBOMS can converge well after training and outperforms the other five baseline algorithms.

关键词： deep reinforcement learning mobile edge computing service caching service migrating

Pylorus-preserving gastrectomy for early gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 653-658页

作者： ke-Kang sun Yong-You Wu Department of Gastrointestinal Surgery The Affiliated Kunshan Hospital to Jiangsu UniversitySuzhou 215300Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Second Affiliated Hospital of Soochow UniversitySuzhou 215008Jiangsu ProvinceChina

Pylorus-preserving gastrectomy(PPG)has been widely accepted as a function-preserving gastrectomy for middle-third early gastric cancer(EGC)with a distal tumor border at least 4 cm proximal to the *** procedure essentially preserves the function of the pyloric sphincter,which requires to preserve the upper third of the stomach and a pyloric cuff at least 2.5 *** suprapyloric and infrapyloric vessels are usually preserved,as are the hepatic and pyloric branches of the vagus *** with distal gastrectomy,PPG has significant advantages in preventing dumping syndrome,body weight loss and bile reflux *** postoperative complications after PPG have reached an acceptable *** can be considered a safe,effective,and superior choice in EGC,and is expected to be extensively performed in the future.

关键词： Gastric cancer Pylorus-preserving gastrectomy Oncological safety Gastric stasis

Research on ECMS Based on Segmented Path Braking Energy Recovery in a Fuel Cell Vehicle

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Energy Engineering 2024年第1期121卷 95-110页

作者： Wen sun Meijing Li Guoxiang Li ke sun Shuzhan Bai School of Energy and Power Engineering Shandong UniversityJinan250061China Automotive Research Institute China National Heavy Duty Truck Group Co.Ltd.Jinan250061China

Proton exchange membrane fuel cells are widely regarded as having the potential to replace internal combustion engines in *** fuel cells cannot recover energy and have a slow dynamic response,they need to be used with different power *** efficient energy management strategies to achieve excellent fuel economy is the goal of *** paper proposes an adaptive equivalent fuel minimum consumption strategy(AECMS)to solve the problem of the poor economy of the whole vehicle caused by the wrong selection of equivalent factors(EF)in traditional *** this method,the kinematics interval is used to update the equivalent factor by considering the penalty term of energy recovery on SOC ***,the optimized equivalent factor is substituted into the optimization objective function to achieve efficient energy *** results under the New European Driving Cycle show that compared with the traditional ECMS based on fixed SOC benchmarks,the proposed method improves fuel economy by 1.7%while ensuring vehicle power and increases SOC by 30%.

关键词： Fuel cell PEMFC electric vehicle equivalent consumption minimization strategy

Sustainable management of campus fallen leaves through low-temperature pyrolysis and application in Pb immobilization

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Journal of Environmental Sciences 2024年第5期139卷 281-292页

作者： Rongli Tan ke Li Yue sun Xiaoliang Fan Zhengtao Shen Lingyi Tang School of Environment Nanjing UniversityNanjing 210023China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China School of Earth and Engineering Sciences Nanjing UniversityNanjing 210023China Department of Earth and Atmospheric Sciences University of AlbertaEdmonton T6G 2E3Canada

Realizing campus sustainability requires the environmental-friendly and economical treatment of tremendous fallen *** fallen leaf biochar at a low temperature is a candidate *** this study,six common types of fallen leaves on the campus were pyrolyzed at 300℃.The obtained biochars were characterized and the adsorption mechanisms of lead(Pb)by the fallen leaf biochars were *** adsorption capacity of leaf biochar for Pb was relatively high,up to 209 mg/g(Yulania denudata leaf biochar).Adsorption of Pb onto active sites was the rate-limiting step for most leaf *** for Platanus leaf biochar,intraparticle diffusion of Pb^(2+)dominated owing to the lowest adsorption ***,the highest exchangeable Pb fraction(27%)indicated its potential for removing aqueous Pb^(2+).Ginkgo and Prunus cerasifera leaf biochar immobilized Pb by surface complexation and precipitation as lead ***,they were suitable for soil heavy metal *** study shed the light on the sustainable utilization of campus fallen leaves and the application of fallen leaf biochars in heavy metal remediation.

关键词： Fallen leaves Waste management Biochar Lead removal Sorption Circular campus

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

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Communications in Theoretical Physics 2024年第5期76卷 77-85页

作者： Duo Zhang ke Wang Kunpeng Zhao Mei Wang Zhaoyu sun School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property

Laser manufacturing of spatial resolution approaching quantum limit

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Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang hong-Hua Fang Zhen-Ze Li Dan Wang hong-Bo sun State key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size of<5 nm is *** underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident *** show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to *** a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

Rapid Energy Exchange between In Situ Formed Bromine Vacancies and CO_(2)Molecules Enhances CO_(2)Photoreduction

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Research 2024年第2期2023卷 763-771页

作者： Qin Ren Ye He hong Wang Yanjuan sun Fan Dong Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China

Photocatalytic reduction of CO_(2)into fuels provides a prospective tactic for regulating the global carbon balance utilizing renewable solar ***,CO_(2)molecules are difficult to activate and reduce due to the thermodynamic stability and chemical *** this work,we develop a novel strategy to promote the adsorption and activation of CO_(2)molecules via the rapid energy exchange between the photoinduced Br vacancies and CO_(2)*** in situ continuous wave-electron paramagnetic resonance(cw-EPR)and pulsed EPR technologies,we observe that the spin-spin relaxation time(T_(2))of BiOBr is decreased by 198 ns during the CO_(2)photoreduction reaction,which is further confirmed by the broadened EPR *** result reveals that there is an energy exchange interaction between in situ formed Br vacancies and CO_(2)molecules,which promotes the formation of high-energy CO_(2)molecules to facilitate the subsequent reduction *** addition,theoretical calculations indicate that the bended CO_(2)adsorption configuration on the surface of BiOBr with Br vacancies caused the decrease of the lowest unoccupied molecular orbital of the CO_(2)molecule,which makes it easier for CO_(2)molecules to acquire electrons and get *** situ diffuse reflectance infrared Fourier transform spectroscopy further shows that the activated CO_(2)molecules are favorably converted to key intermediates of COOH*,resulting in a CO generation rate of 9.1μmol g^(-1)h^(-1)and a selectivity of 100%.This study elucidates the underlying mechanism of CO_(2)activation at active sites and deepens the understanding of CO_(2)photoreduction reaction.

关键词： reaction. adsorption activation