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Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 461-478页

作者： Haitao LI Tianyu ZHENg Weiyang QIN Ruilan TIAN Hu DINg J.c.ji Liqun cHEN Department of Engineering Mechanics North University of ChinaTaiyuan 030051China Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and *** the combined energy of vibration and wind with a single energy harvesting structure is *** this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy *** results of the analytical prediction are verified with the Monte-carlo method(McM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base ***,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed *** experiments are conducted to investigate the validity of the theoretical prediction and numerical *** experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind ***,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

coordination for a closed-loop Supply chain with Recycling Platform considering Dynamic Setting

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 425-451页

作者： Zehua Xiang Ting ji Lingfeng Dong School of Management Zhejiang UniversityHangzhou310058China School of Business Hangzhou City UniversityHangzhou310015China Alibaba Business college Hangzhou Normal UniversityHangzhou311121China

This paper presents a dynamic closed-loop supply chain(cLSc)model,incorporating a manufacturer,a retailer,and an internet recycling platform(IRP),utilizing differential game theory while considering the forgetting effect of *** model encompasses factors such as the quality level of used products and Big Data marketing(BDM),comparing optimal equilibriums under decentralized and cooperative decision *** effectively coordinate the dynamic cLSc at each time point,we propose a revenue-sharing and cost-sharing(RScS)combined *** addition to ensuring reasonable sharing of revenues and costs,this contract allows the manufacturer to flexibly adjust wholesale prices for final products and transfer prices for used products in order to distribute profits appropriately and achieve Pareto optimality within the cLSc ***,our results indicate that there exists a threshold for Big Data marketing efficiency;high-efficiency BDM not only facilitates increased recycling on Internet platforms but also reduces unit recycling costs for ***,when implementing the combined contract,Big Data marketing efficiency does not impact the transfer price paid by manufacturers to Internet recycling platforms.

关键词： Big Data marketing differential game closed-loop supply chain coordination internet recycling platform

Effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens

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Eye and Vision 2024年第3期10卷 31-40页

作者： Lingling Niu Zhe Zhang Huamao Miao jing Zhao Xiaoying Wang ji c.He Xingtao Zhou Department of Ophthalmology and Optometry Eye&ENT HospitalFudan UniversityShanghaiChina NHc Key Laboratory of Myopia(Fudan University) ShanghaiChina Key Laboratory of Myopia Chinese Academy of Medical SciencesShanghaiChina Shanghai Research center of Ophthalmology and Optometry ShanghaiChina New England college of Optometry MABostonUSA

Background To investigate the effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens(IcL V4c).Methods This observational study recruited 62 eyes of 31 myopia patients underwent IcL V4c *** segment optical coherence tomography(AS-OcT)assessed the anterior chamber depth(AcD),AcD-IcL(distance from the corneal endothelium to anterior surface of the IcL V4c),vault(distance between the posterior IcL V4c surface and anterior crystalline lens surface),and crystalline lens tilt under various lighting conditions and accommodation relative to the corneal topographic axis at one year after IcL V4c *** was defined as the scotopic condition,which was also the non-accommodative stimulus *** IcL V4c tilt was analyzed using *** significance level was set at PcD-IcL values were similar under various lighting conditions(P=0.978)but decreased during accommodation(Pgnificantly smaller under mesopic and photopic conditions than the baseline(P=0.044 and Pctively)but remained unchanged during accommodation(P=0.058).The inferotemporal proportion of IcL V4c(88.7%,55 eyes)and crystalline lens(74.2%,46 eyes)tilts were not significantly different(P=0.063).crystalline lens under various lighting conditions and accommodation exhibited similar *** vertical tilt of IcL V4c was significantly larger under photopic conditions than the baseline(P=0.038).The horizontal and total tilts were significantly decreased during accommodation(P=0.043 and 0.013,respectively).conclusions The axial position of IcL V4c in the anterior chamber was stable under various lighting *** conditions and accommodation may influence vertical,horizontal and total tilts of IcL V4c.

关键词： Implantable collamer lens Anterior segment optical coherence tomography Myopia Tilt

Semi-derived Ringel-Hall algebras and Hall algebras of odd-periodic relative derived categories

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Science china Mathematics 2024年第8期67卷 1735-1760页

作者： ji Lin Liangang Peng Department of Mathematics and Statistics Fuyang Normal UniversityFuyang 236037China School of Mathematics Sichuan UniversityChengdu 610064China

Let t be a positive integer and A be a hereditary abelian category satisfying some finiteness *** define the semi-derived Ringel-Hall algebra of A from the category c_(Z/t)(A)of Z/t-graded complexes and obtain a natural basis of the semi-derived Ringel-Hall ***,we describe the semiderived Ringel-Hall algebra by the generators and defining *** particular,if t is an odd integer,we show an embedding of the derived Hall algebra of the odd-periodic relative derived category in the extended semi-derived Ringel-Hall algebra.

关键词： hereditary abelian categories the categories of Z/t-graded complexes semi-derived Ringel-Hall algebras derived Hall algebras

Resonantly enhanced second-and third-harmonic generation in dielectric nonlinear metasurfaces

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Opto-Electronic Advances 2024年第5期7卷 5-19页

作者： ji Tong Wang Pavel Tonkaev Kirill Koshelev Fangxing Lai Sergey Kruk Qinghai Song Yuri Kivshar Nicolae c.Panoiu Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUnited Kingdom Nonlinear Physics center Research School of PhysicsAustralian National UniversityCanberra ACT 2601Australia Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic SystemsHarbin Institute of TechnologyShenzhen 518055China Wuzhen Laboratory EGO Wuzhen Digital Economy Industrial ParkNo.925 Daole RoadTongxiangChina

Nonlinear dielectric metasurfaces provide a promising approach to control and manipulate frequency conversion optical processes at the nanoscale,thus facilitating both advances in fundamental research and the development of new practical applications in photonics,lasing,and ***,we employ symmetry-broken metasurfaces made of centrosymmetric amorphous silicon for resonantly enhanced second-and third-order nonlinear optical *** the rich physics of optical quasi-bound states in the continuum and guided mode resonances,we comprehensively study through rigorous numerical calculations the relative contribution of surface and bulk effects to second-harmonic generation(SHg)and the bulk contribution to third-harmonic generation(THg) from the ***,we experimentally achieve optical resonances with high quality factors,which greatly boosts light-matter interaction,resulting in about 550 times SHg enhancement and nearly 5000-fold increase of THg.A good agreement between theoretical predictions and experimental measurements is *** gain deeper insights into the physics of the investigated nonlinear optical processes,we further numerically study the relation between nonlinear emission and the structural asymmetry of the metasurface and reveal that the generated harmonic signals arising from linear sharp resonances are highly dependent on the asymmetry of the *** work suggests a fruitful strategy to enhance the harmonic generation and effectively control different orders of harmonics in all-dielectric metasurfaces,enabling the development of efficient active photonic nanodevices.

关键词： second-harmonic generation third-harmonic generation bound state in the continuum guided mode resonance all-dielectric metasurfaces nonlinear optics

Endogenous Trypsin Triggers Free Fluoride Release from Antarctic Krill(Euphausia superba)cuticle

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Journal of Ocean University of china 2024年第3期23卷 766-774页

作者： PENg Yuanhuai ji Wei ji Hongwu HAN Zhiping ZHANg Shiqi WEN Yaping college of Food Science and Engineering Lingnan Normal UniversityZhanjiang 524048China college of Biological and Food Engineering Guangdong University of EducationGuangzhou 510303China guangdong Provincial Key Laboratory of Aquatic Products Processing and Safety Guangdong Ocean UniversityZhanjiang 524088China college of Food Science and Technology Guangdong Ocean UniversityZhanjiang 524088China college of continuing Education Lingnan Normal UniversityZhanjiang 524048China

During postmortem storage,fluoride in Antarctic krill can be enriched in the ***,as the most important digestive enzyme in Antarctic krill with a high activity in low temperature,plays a potential role in this *** this study,endogenous trypsin was purified and its properties were *** involvement of trypsin in the generation of free fluoride from Antarctic krill cuticle was *** microstructure before and after hydrolysis was compared with scanning electron microscopy,and the ash samples of the hydrolyzed Antarctic krill cuticle were analyzed with X-ray diffraction,Fourier transform infrared spectroscopy,and electron dispersive spectroscopy,*** spectrometry analysis and inhibition tests confirmed that the purified enzyme was endogenous *** of the present study indicated that trypsin digestion caused the increases of the concentrations of both fluoride ions and free amino N simultaneously,while the protein coated on the cuticle surface was dissolved ***,no compositional change was detected in the cuticle inorganic *** findings suggest that trypsin triggered free fluoride release from Antarctic krill *** addition,the kinetics of free fluoride release could be described by the equation c_(W)=(1-0.97^(-0.006t)-0.03e^(0.0558t))×337.53+*** present study improved the understanding of the role of trypsin in free fluoride release from Antarctic krill cuticle,facilitating future studies aimed at reducing the fluoride content in krill protein during Antarctic krill processing.

关键词： Antarctic krill cuticle fluoride trypsin

Effect of structural characteristics on the transport characteristics of solid particles in the thermal storage and release system of circulating fluidized bed

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Particuology 2024年第6期89卷 22-31页

作者： Zengcai ji guoliang Song Zihua Tang Liwei Sun Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of chinese Academy of Sciences Beijing100049China Dalian National Laboratory for clean Energy Dalian116023China

coal-fired power generation stands as the most economically viable modulating power source in present-day *** holds the potential to offer prospective solutions to the challenges posed by the rapid expansion of intermittent,unpredictable,and unstable renewable energy *** particle thermal storage technology emerges as an effective means to enhance the flexibility of coal-fired circulating fluidized bed power *** attain an optimized structure for the solid particle thermal storage and release system in circulating fluidized bed units,experimental research was conducted on a 0.1 MWth circulating fluidized bed test *** study delved into the impact of ash storage bin geometries and the shapes of their feed-discharge valves on the control properties of solid particle *** experimental outcomes reveal that employing inverted m-shaped valve and dual U-shaped valves for feed control,alongside U-shaped valves and N-shaped valves for discharge control,both enable efficient and rapid storage and release of solid particles within the circulating fluidized *** similar air distribution conditions,the inverted m-shaped valve exhibits lower conveying energy consumption than the dual U-shaped valves,while the N-shaped valve excels in control characteristics over the U-shaped ***,the inverted m-shaped valve and the N-shaped valve demonstrate optimal overflow port heights,and the ash storage bin exhibits an optimum height-to-diameter ratio.

关键词： Solid particle Thermal storage System structure Transport regulation

Role of catalyst surface-active sites in the hydrogenation ofα,β-unsaturated aldehyde

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Frontiers of chemical Science and Engineering 2024年第6期18卷 41-69页

作者： Haixiang Shi Tongming Su Zuzeng Qin Hongbing ji School of chemistry and chemical Engineering Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification TechnologyGuangxi UniversityNanning 530004China Zhejiang green Petrochemical and Light Hydrocarbon Transformation Research Institute Zhejiang University of TechnologyHangzhou 310014China

As an important technology in fine chemical production,the selective hydrogenation ofα,β-unsaturated aldehydes has attracted much attention in recent *** the process ofα,β-unsaturated aldehyde hydrogenation,a conjugated system is formed between>c=cc=O,leading to hydrogenation at both ends of the conjugated system,which competes with each other and results in more complex ***,improving the reaction selectivity is also difficult in industrial ***,many researchers have reported that surface-active sites on catalysts play a crucial role inα,β-unsaturated aldehyde *** review attempts to summarize recent advances in understanding the effects of surface-active sites(SASs)over metal catalysts for enhancing the process of *** construction strategies and roles of SASs for hydrogenation catalysts are *** attention has been given to the adsorption configuration and transformation mechanism ofα,β-unsaturated aldehydes on catalysts,which contributes to understanding the relationship between SASs and hydrogenation *** addition,recent advances in metal-supported catalysts for the selective hydrogenation ofα,β-unsaturated aldehydes to understand the role of SASs in hydrogenation are briefly ***,the opportunities and challenges will be highlighted for the future development of the precise construction of SASs.

关键词： α,β-unsaturatedd aldehydes hydrogenation active site cinnamaldehyde

Forced boiling of nonazeotropic immiscible mixture in a supercapillary microchannel array for ultra-high heat flux removal with chip junction temperature below 85℃

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Science china(Technological Sciences) 2024年第5期67卷 1364-1380页

作者： SUN Bo BAO Yuchen TIAN Tong LI ji School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Laboratory of Advanced Thermal Management Technologies School of Engineering ScienceUniversity of Chinese Academy of SciencesBeijing100049China

In this study,a structure-optimized two-phase microchannel heat sink with sintered submicron nucleation sites was developed and *** copper-based microchannels had a rectangular cross-section with an equivalent hydraulic diameter of 222μ*** subcooled flow boiling characteristics were comprehensively compared between pure HFE-7100 and a non-azeotropic,immiscible binary mixture of HFE-7100 and water,considering heating areas of 1 and 5 cm^(2).The total heating power input to the test section were 100–1500 and 250–3000 W for a 1 and 5 cm^(2)heat source,respectively,with a flow rate ranging from 50 to150 L/*** to pure HFE-7100,the non-azeotropic immiscible binary mixture of HFE-7100/water in the sintered porous microchannels exhibited a much higher overall heat transfer coefficient and lower power *** maintain the junction temperature of a high power electronic chip below 85℃,the proposed supercapillary microchannel heat sink could effectively dissipate the heat flux of 1275 W/cm^(2)over 1 cm^(2)heat source and 500 W/cm^(2)over 5 cm^(2)heat *** addition,the volume ratio of the binary mixture strongly influence the two-phase flow heat transfer *** optimal volume ratio exist in terms of the thermal resistance–pumping power minimization(HFE-7100:water=2:8 is recommended in this study).The findings of this investigation on the flow boiling properties of non-azeotropic immiscible mixtures help fill a gap in the related field.

关键词： microchannel sintered powder coating submicron nucleation cavities nonazeotropic immiscible ultra-high heat flux