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Acta Mechanica Sinica 2010年第4期26卷 509-520页

作者： yan-lai zhang mao sun Ministry-of-Education Key Laboratory of Fluid Mechanics Institute of Fluid Mechanics Beihang University 100191 Beijing China

In the present paper, the longitudinal dynamic flight stability properties of two model insects are predicted by an approximate theory and computed by numerical sim- ulation. The theory is based on the averaged model （which assumes that the frequency of wingbeat is sufficiently higher than that of the body motion, so that the flapping wings＇ degrees of freedom relative to the body can be dropped and the wings can be replaced by wingbeat-cycle-average forces and moments）; the simulation solves the complete equations of motion coupled with the Navier-Stokes equations. Comparison between the theory and the simulation provides a test to the validity of the assumptions in the theory. One of the insects is a model dronefly which has relatively high wingbeat frequency （164 Hz） and the other is a model hawkmoth which has relatively low wingbeat frequency （26 Hz）. The results show that the averaged model is valid for the hawkmoth as well as for the dronefly. Since the wingbeat frequency of the hawkmoth is relatively low （the characteristic times of the natural modes of motion of the body divided by wingbeat period are relatively large） compared with many other insects, that the theory based on the averaged model is valid for the hawkmoth means that it could be valid for many insects.

关键词： Insect Hovering Dynamic flight stability Averaged model Equations-of-motion Navier-Stokes simulation

Stabilization control of a hovering model insect:lateral motion

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Acta Mechanica Sinica 2011年第5期27卷 823-832页

作者： yan-lai zhang mao sun Ministry-of-Education Key Laboratory of Fluid Mechanics Beihang University 100191 Beijing China

Our previous study shows that the lateral disturbance motion of a model drone fly does not have inherent stability （passive stability）,because of the existence of an unstable divergence *** drone flies are observed to fly *** active control must be applied to stabilize the *** this study,we investigate the lateral stabilization control of the model drone *** method of computational fluid dynamics is used to compute the lateral control derivatives and the techniques of eigenvalue and eigenvector analysis and modal decomposition are used for solving the equations of *** analysis shows that although inherently unstable,the lateral disturbance motion is *** feeding back the state variables （*** translation velocity,yaw rate,roll rate and roll angle,which can be measured by the sensory system of the insect） to produce anti-symmetrical changes in stroke amplitude and/or in angle of attack between the left and right wings,the motion can be stabilized,explaining why the drone flies can fly stably even if the flight is passively unstable.

关键词： Hovering drone fly Lateral motion Flight stability Stabilization control Modal analysis

Potassium ions and cyano group modified g-C_(3)N_(4) for effective generation of H_(2)O_(2) through two-electron oxygen reduction

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Science China Chemistry 2025年第1期68卷 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen Ke Lei Yujie Duan Linjiao mao Xuhui Zeng Xi Luo Yuntao zhang Yuqin Dong Jin Zhong zhang yan sun School of Mechanical Engineering Chengdu UniversityChengdu 610106China Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCA 95064USA

Potassium ions(K^(+))doped graphitic carbon nitride(g-C_(3)N_(4))was prepared by a thermal etching method using potassium hydroxide(KOH)as an ion *** transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results showed that the generation of the cyano group was detected while introducing K^(+).Under simulated sunlight irradiation,the sample with a K^(+)doping amount of 10%showed the highest hydrogen peroxide(H_(2)O_(2))generation rate of2,140.2μmol h^(-1)g^(-1).The apparent quantum yield(AQY)at 400 nm and the solar-to-chemical conversion(SCC)are 4.35%and1.23%,respectively.K^(+)acted as a bridge between g-C_(3)N_(4)layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons(H^(+))and promoted the yield of H_(2)O_(2).The catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals(·O_(2)^(-))were the most important active species in the reaction *** production of H_(2)O_(2)was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H_(2)O_(2)generation.

关键词： photocatalysis hydrogen peroxide oxygen reduction reaction potassium doping cyano group

Characterization of petrophysical and seismic properties for CO2 storage with sensitivity analysis

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Petroleum Science 2025年第1期22卷 193-209页

作者： yan-Jiao Dong Yi Shen Kai Guo Xiao-Qin Wu Qiang mao Wen-Yue sun Zhi-Qiang Wang State Key Laboratory of Offshore Oil and Gas Exploitation Geosciences Department China University of Petroleum (East China) CNOOC Research Institute Ltd. School of Petroleum Engineering China University of Petroleum (East China)

Saline aquifers are considered as highly favored reservoirs for CO2sequestration due to their favorable properties. Understanding the impact of saline aquifer properties on the migration and distribution of CO2plume is crucial. This study focuses on four key parameters—permeability, porosity, formation pressure, and temperature—to characterize the reservoir and analyse the petrophysical and elastic response of CO2. First, we performed reservoir simulations to simulate CO2saturation, using multiple sets of these four parameters to examine their significance on CO2saturation and the plume migration ***, the effect of these parameters on the elastic properties is tested using rock physics *** established a relationship of compressional wave velocity（Vp） and quality factor（Qp） with the four key parameters, and conducted a sensitivity analysis to test their sensitivity to Vpand Qp. Finally, we utilized visco-acoustic wave equation simulated time-lapse seismic data based on the computed Vpand Qpmodels, and analysed the impact of CO2saturation changes on seismic data. As for the above numerical simulations and analysis, we conducted sensitivity analysis using both homogeneous and heterogeneous models. Consistent results are found between homogeneous and heterogeneous models. The permeability is the most sensitive parameter to the CO2saturation, while porosity emerges as the primary factor affecting both Qpand Vp. Both Qpand Vpincrease with the porosity, which contradicts the observations in gas reservoirs. The seismic simulations highlight significant variations in the seismic response to different parameters. We provided analysis for these observations, which serves as a valuable reference for comprehensive CO2integrity analysis, time-lapse monitoring, injection planning and site selection.

关键词： CO2 storage Time-lapse seismic CO2 plume Sensitivity analysis Rock physics Reservoir simulation Saline aquifer

Recent Advances in Wide-Range Temperature Metal-CO_(2)Batteries:A Mini Review

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Nano-Micro Letters 2025年第4期17卷 435-453页

作者： Xuejing zhang Ning Zhao Hanqi zhang Yiming Fan Feng Jin Chunsheng Li yan sun Jiaqi Wang Ming Chen Xiaofei Hu School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003People’s Republic of China Engineering Research Center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi’an Jiaotong UniversityXi’an 710049People’s Republic of China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China School of Chemistry and Life SciencesSuzhou University of Science and TechnologySuzhou 215009People’s Republic of China Department of Chemistry and Biochemistry Northern Illinois UniversityDeKalbIL 60115USA School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002People’s Republic of China

The metal-carbon dioxide batteries,emerging as high-energy-density energy storage devices,enable direct CO_(2)utilization,offering promising prospects for CO_(2)capture and utilization,energy conversion,and ***,the electrochemical performance of M-CO_(2)batteries faces significant challenges,particularly at extreme *** such as high overpotential,poor charge reversibility,and cycling capacity decay arise from complex reaction interfaces,sluggish oxidation kinetics,inefficient catalysts,dendrite growth,and unstable *** significant advancements at room temperature,limited research has focused on the performance of M-CO_(2)batteries across a wide-temperature *** review examines the effects of low and high temperatures on M-CO_(2)battery components and their reaction mechanism,as well as the advancements made in extending operational ranges from room temperature to extremely low and high *** discusses strategies to enhance electrochemical performance at extreme temperatures and outlines opportunities,challenges,and future directions for the development of M-CO_(2)batteries.

关键词： M-CO_(2)batteries Wide-range temperature Electrolytes Interfaces Electrode reactions

Rab1 and Syntaxin 17 regulate hematopoietic homeostasis through β-integrin trafficking in Drosophila

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Journal of Genetics and Genomics 2025年第1期52卷 51-65页

作者： Fangzhou Luo Luwei Sui Ying sun Zhixian lai Chengcheng zhang Gaoqun zhang Bing Bi Shichao Yu Li Hua Jin College of Life Sciences Northeast Forestry UniversityHarbinHeilongjiang 150040China Department of Developmental Immunology Max Planck Institute of Immunobiology and EpigeneticsFreiburgGermany

Hematopoiesis is crucial for organismal health,and Drosophila serves as an effective genetic model due to conserved regulatory mechanisms with *** larvae,hematopoiesis primarily occurs in the lymph gland,which contains distinct zones,including the cortical zone,intermediate zone,medullary zone,and posterior signaling center(PSC).Rab1 is vital for membrane trafficking and maintaining the localization of cell adhesion molecules,yet its role in hematopoietic homeostasis is not fully *** study investigates the effects of Rab1 dysfunction on β-integrin trafficking within circulating hemocytes and lymph gland ***1 impairment disrupts the endosomal trafficking of β-integrin,leading to its abnormal localization on cell membranes,which promotes lamellocyte differentiation and alters progenitor dynamics in circulating hemocytes and lymph glands,*** also show that the mislocalization of β-integrin is dependent on the adhesion protein *** reduction of β-integrin at cell boundaries in PSC cells leads to fewer PSC cells and lamellocyte ***,Rab1 regulates the trafficking of β-integrin via the Q-SNARE protein Syntaxin 17(Syx17).Our findings indicate that Rab1 and Syx17 regulate distinct trafficking pathways for β-integrin in different hematopoietic compartments and maintain hematopoietic homeostasis of Drosophila.

关键词： Hematopoiesis Lymphgland Rab1 Syntaxin 17 β-integrin Drosophila

Semiparametric Additive Hazards Model with Doubly Truncated Data

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Acta Mathematica Sinica,English Series 2025年第2期41卷 619-639页

作者： Yijin zhang Liuquan sun Institute of Applied Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Doubly truncated data arise when the survival times of interest are observed only if they fall within certain random *** this paper,we consider a semiparametric additive hazards model with doubly truncated data,and propose a weighted estimating equation approach to estimate the regression coefficients,where the weights are estimated both parametrically and *** asymptotic properties of the resulting estimators are *** studies demonstrate that the proposed estimators perform well in a finite *** application to Parkinson's disease data is provided.

关键词： Additive hazards model double truncation estimating equations inverse weighting survival analysis

Protonated carbon nitride for rapid photocatalytic sterilization via synergistic oxidative damage and physical destruction

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Journal of Environmental Sciences 2025年第3期149卷 188-199页

作者： Xiaobiao Zhu Chunhong Xu Jie mao Yizhen zhang Yaohui Bai Department of Environmental Science and Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic *** strategies have been devised to facilitate the generation of reactive oxygen species(ROS)within photocatalysts,ultimately leading to the eradication of ***,the significance of the physical morphology of photocatalysts in the context of sterilization is frequently obscured,and the progress in the development of physical-chemical synergistic sterilization photocatalysts has been relatively ***,graphitic carbon nitride(g-C_(3)N_(4))is chemically protonated to expose more sharp *** fluorescence and EIS results indicate that the protonation can accelerate photogenerated carrier separation and enhance ROS ***,the sharp edges on the protonated g-C_(3)N_(4)facilitate the physical disruption of cell walls for further promoting oxidative *** C_(3)N_(4)demonstrated superior bactericidal performance than that of pristine g-C_(3)N_(4),effectively eliminating Escherichia coli within 40 minutes under *** work highlights the significance of incorporating physical and chemical synergies in photocatalyst design to enhance the disinfection efficiency of photocatalysis.

关键词： Protonated Photocatalytic Sterilization Synergistic Oxidative Damage Physical Destruction

Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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Nano-Micro Letters 2025年第3期17卷 340-354页

作者： Li An Jianyi Li Yuanmiao sun Jiamin Zhu Justin Zhu Yeow Seow Hong zhang Nan zhang Pinxian Xi Zhichuan J.Xu Chun‑Hua yan State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceFrontiers Science Center for Rare IsotopesCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000People’s Republic of China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Faculty of Materials Science and Energy Engineering Institute of Technology for Carbon NeutralityShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Key Laboratory of Electromagnetic Materials and Devices National Center for International Research On Photoelectric and Energy MaterialsSchool of Materials and EnergyElectron Microscopy CenterYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030People’s Republic of China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU‑HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871People’s Republic of China

Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution *** surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity ***,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is *** substituting Fe content influences both current change tendency and surface reconstruction ***_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)*** reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based ***,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term ***,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction *** effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface *** finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

A Verifiable Trust-Based CP-ABE Access Control Scheme for Cloud-Assisted Renewable Energy Systems

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Computers, Materials & Continua 2025年第1期82卷 1211-1232页

作者： Jiyu zhang Kehe Wu Ruomeng yan Zheng Tian Yizhen sun Yuxi Wu Yaogong Guo Department of Control and Computer Engineering North China Electric Power UniversityBeijing102206China State Grid Information&Communication Company of Hunan Electric Power Corporation Changsha410118China State Grid Hunan Electric Power Corporation Chenzhou Power Supply Branch Chenzhou423000China

Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research ***,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for *** address these security concerns,a trust-based ciphertext-policy attribute-based encryption(CP-ABE)device access control scheme is proposed for RES(TB-CP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key *** introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive ***,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s *** validate the security of the proposed TB-CP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)***,comparative analysis with other schemes demonstrates that the TB-CP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service *** proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions.

关键词： Access control renewable energy systems(RES) ciphertext-policy attribute-based encryption(CP-ABE) security