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Reconstructing forest and grassland cover changes in China over the past millennium

Science China Earth Sciences 2025年第1期68卷 94-110页

作者： fanneng he fan yang Yafei WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of Sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

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On-chip stackable dielectric laser accelerator

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Nuclear Science and Techniques 2023年第2期34卷 79-87页

作者： Bin Sun yang‑fan he Ruo‑Yun Luo Tai‑yang Zhang Qiang Zhou Shao‑Yi Wang Jian Zheng Zong‑Qing Zhao CAS Key Laboratory of Geospace Environment Department of Plasma Physics and Fusion EngineeringUniversity of Science and Technology of ChinaHefei 230026China Laser Fusion Research Center CAEPP.O.Box 919986Mianyang 621900China The Sciences and Technology on Plasma Physics Laboratory CAEPMianyang 621900China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Nuclear Plasmaand Radiological EngineeringUniversity of Illinois at Urbana-Champaign104 South Wright StreetUrbanaIL 61801USA CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China

In this paper,we propose a novel stacked laser dielectric acceleration *** structure is based on the inverse Cherenkov effect and represented by a parametric design *** to existing dielectric laser accelerators relying on the inverse Smith–Purcell effect,the proposed structure provides an extended-duration synchronous acceleration field without requiring the pulse front tilting *** advantage significantly reduces the required pulse *** addition,the easy to integrate layered structure facilitates cascade acceleration,and simulations have shown that low-energy electron beams can be cascaded through high gradients over extended *** practical advantages demonstrate the potential of this new structure for future chip accelerators.

关键词： Dielectric laser accelerator Inverse Cherenkov effect Laser-driven particle acceleration

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Topology optimization of on-chip integrated laser-driven particle accelerator

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Nuclear Science and Techniques 2022年第9期33卷 126-136页

作者： yang-fan he Bin Sun Ming-Jiang Ma Wei Li Qiang-You he Zhi-Hao Cui Shao-Yi Wang Zong-Qing Zhao Laser Fusion Research Center CAEPP.O.Box 919986Mianyang 621900China The Sciences and Technology on Plasma Physics Laboratory CAEPMianyang 621900China Department of Plasma Physics and Fusion Engineering CAS Key Laboratory of Geospace EnvironmentUniversity of Science and Technology of ChinaHefei 230026China The Institute of Optics University of RochesterRochesterNY 14627USA

Particle accelerators are indispensable tools in both science and ***,the size and cost of conventional RF accelerators limits the utility and scope of this *** research has shown that a dielectric laser accelerator(DLA)made of dielectric structures and driven at optical frequencies can generate particle beams with energies ranging from MeV to GeV at the tabletop *** design DLA structures with a high acceleration gradient,we demonstrate topology optimization,which is a method used to optimize the material distribution in a specific area based on given load conditions,constraints,and performance *** demonstrate the effectiveness of this approach,we propose two schemes and design several acceleration structures based on *** optimization results demonstrate that the proposed method can be applied to structure optimization for on-chip integrated laser accelerators,producing manufacturable structures with significantly improved performance compared with previous size or shape optimization *** results provide new physical approaches to explore ultrafast dynamics in matter,with important implications for future laser particle accelerators based on photonic chips.

关键词： Laser-driven particle acceleration Dielectric grating accelerator Inverse Smith-Purcell effect Topology optimization

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Study on γ-ray source from the resonant reaction ^19F(p,αγ)^16O at Ep=340 keV

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Chinese Physics B 2020年第7期29卷 269-274页

作者： Fu-Long Liu Wan-Sha yang Ji-Hong Wei Di Wu yang-fan he Yu-Chen Li Tian-Li Ma yang-Ping Shen Qi-Wen fan Chuang-Ye he Bing Guo Nai-Yan Wang Key Laboratory of Radiation Beam Technology and Materials Modification of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China China Institute of Atomic Energy Beijing 102413China Beijing Radiation Center Beijing 100875China

High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine *** of the methods to generate high-energyγ-ray is nuclear resonant *** 19F(p,αγ)16O reaction was used to generate 6.13-MeVγ-ray in this *** angular distribution of 6.13-MeVγ-ray was measured by six LaBr3 *** thick-target yield curve of 6.13-MeVγ-ray had been *** maximum yield was determined to be(1.85±0.01)×10^-8γ/proton,which was measured by HPGe detector and LaBr3 *** absolute efficiency of all the detectors was calibrated using 60Co and 27Al(p,γ)^28Si reaction at Ep=992 *** cross section and total resonant width of the reaction were determined to be 95.1±1.0 mb(1 b=10^-24 cm^2)andΓCM=2.21±0.22 keV,respectively.

关键词： high-energyγ-ray source thick-target yield resonant reaction cross section

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Calibration of CR-39 solid-state track detectors for study of laser-driven nuclear reactions

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Nuclear Science and Techniques 2020年第4期31卷 118-122页

作者： yang-fan he Xiao-Feng Xi Shi-Lun Guo Bing Guo Chuang-Ye he Fu-Long Liu Di Wu Ji-Hong Wei Wan-Sha yang Luo-Huan Wang Dong-Hai Zhang Meng-Lin Qiu Guang-Fu Wang Chao-yang Li Xiao-Fei Lan School of Physics and Space Sciences China West Normal UniversityNanchong 637002China China Institute of Atomic Energy Beijing 102413China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China School of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004China

It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical *** have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser *** this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction *** measure the dependence of the track diameter on the proton *** is found that the track diameters of protons with different energies are likely to be *** propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these *** present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.

关键词： Big bang nucleosynthesis Laser-driven nuclear reactions CR-39 detectors Gray levels

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Joint Estimation of SOH and RUL for Lithium-Ion Batteries Based on Improved Twin Support Vector Machineh

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Energy Engineering 2025年第1期122卷 243-264页

作者： Liyao yang HongyanMa Yingda Zhang Wei he School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China Institute of Distributed Energy Storage Safety Big Data Beijing100044China Beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing100044China

Accurately estimating the State of health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management ***,due to the complex internal chemical systems of LIBs and the nonlinear degradation of their performance,direct measurement of SOH and RUL is *** address these issues,the Twin Support Vector Machine(TWSVM)method is proposed to predict SOH and ***,the constant current charging time of the lithium battery is extracted as a health indicator(HI),decomposed using Variational Modal Decomposition(VMD),and feature correlations are computed using Importance of Random Forest Features(RF)to maximize the extraction of critical factors influencing battery performance ***,to enhance the global search capability of the Convolution Optimization Algorithm(COA),improvements are made using Good Point Set theory and the Differential Evolution *** Improved Convolution Optimization Algorithm(ICOA)is employed to optimize TWSVM parameters for constructing SOH and RUL prediction ***,the proposed models are validated using NASA and CALCE lithium-ion battery *** results demonstrate that the proposed models achieve an RMSE not exceeding 0.007 and an MAPE not exceeding 0.0082 for SOH and RUL prediction,with a relative error in RUL prediction within the range of[-1.8%,2%].Compared to other models,the proposed model not only exhibits superior fitting capability but also demonstrates robust performance.

关键词： State of health remaining useful life variational modal decomposition random forest twin support vector machine convolutional optimization algorithm

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Structure and material study of dielectric laser accelerators based on the inverse Cherenkov effect

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Chinese Physics B 2023年第9期32卷 250-254页

作者：孙斌何阳帆罗若云章太阳周强王少义王度赵宗清 Department of Plasma Physics and Fusion Engineering Key Laboratory of Geospace EnvironmentUniversity of Science and Technology of ChinaHefei 230026China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China The Sciences and Technology on Plasma Physics Laboratory CAEPMianyang 621900China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Nuclear Plasmaand Radiological EngineeringUniversity of Illinois at Urbana-Champaign104 South Wright StreetUrbanaIL 61801USA CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Dielectric laser accelerators(DLAs)are considered promising candidates for on-chip particle accelerators that can achieve high acceleration *** study explores various combinations of dielectric materials and accelerated structures based on the inverse Cherenkov *** designs utilize conventional processing methods and laser parameters currently in *** optimize the structural model to enhance the gradient of acceleration and the electron energy *** achieve higher acceleration gradients and energy gains,the selection of materials and structures should be based on the initial electron ***,we observed that the variation of the acceleration gradient of the material is different at different initial electron *** findings suggest that on-chip accelerators are feasible with the help of these structures and materials.

关键词： dielectric laser accelerator high gradient accelerator inverse Cherenkov effect accelerated structure and material

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Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China Life Sciences 2025年第1期68卷 300-302页

作者： Ze-Min Lin Mai Xiang Wen-Hui Wei Shu-Hui fan Li Chen Jie Wang Xiao-Qian yang Chun-Hao yang Shi-Jun he Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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Defect Engineering:Can it Mitigate Strong Coulomb Effect of Mg^(2+)in Cathode Materials for Rechargeable Magnesium Batteries?

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Nano-Micro Letters 2025年第1期17卷 135-159页

作者： Zhengqing fan Ruimin Li Xin Zhang Wanyu Zhao Zhenghui Pan Xiaowei yang School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China School of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024People’s Republic of China School of Materials Science and Engineering Tongji UniversityShanghai 201804People’s Republic of China

Rechargeable magnesium batteries(RMBs)have been considered a promising“post lithium-ion battery”system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage ***,the sluggish diffusion kinetics of bivalent Mg^(2+)in the host material,related to the strong Coulomb effect between Mg^(2+)and host anion lattices,hinders their further development toward practical *** engineering,regarded as an effective strategy to break through the slow migration puzzle,has been validated in various cathode materials for *** this review,we first thoroughly understand the intrinsic mechanism of Mg^(2+)diffusion in cathode materials,from which the key factors affecting ion diffusion are further ***,the positive effects of purposely introduced defects,including vacancy and doping,and the corresponding strategies for introducing various defects are *** applications of defect engineering in cathode materials for RMBs with advanced electrochemical properties are also ***,the existing challenges and future perspectives of defect engineering in cathode materials for the overall high-performance RMBs are described.

关键词： Rechargeable magnesium battery Sluggish diffusion kinetic Defect engineering Cathode materials Ion migration

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Effect of Progressive Substitution of Cement and Lime by Powdered Shells Used as a Curing Agent for Dredged Soil in a Port Area

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 88-102页

作者： SUN yang WANG Faxin SU Yaying LI Yiwei he Feng College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Huai'an Research Institute Hohai UniversityHuai'an 223025China Jiangsu fangyang Industrial Investment Corp.Ltd. Lianyungang 210098China

This study aimed to address the challenges of solid waste utilization,cost reduction,and carbon reduction in the treatment of deep-dredged soil at Xuwei Port in Lianyungang city of *** research in this area was ***,a curing agent made from powdered shells was used to solidify the dredged soil in *** employed laboratory orthogonal tests to investigate the physical and mechanical properties of the powdered shell-based curing *** was collected by conducting experiments to assess the role of powdered shells in the curing process and to determine the optimal ratios of powdered shells to solidified soil for different *** development of strength in solidified soil was studied in both seawater and pure water *** study revealed that the strength of the solidified soil was influenced by the substitution rate of powdered shells and their interaction with *** cement content had a positive effect on *** high-strength solidified soil,the recommended ratio of wet soil:cement:lime:powdered shells were 100:16:4:4,while for low-strength solidified soil,the recommended ratio was 100:5.4:2.4:***,under appropriate conditions,improved short-term strength by promoting the formation of expansive ettringite minerals that contributed to cementation and *** findings suggest that the combination of cement and powdered shells is synergistic,positively affecting the strength of solidified *** recommended ratios provide practical guidance for achieving desired strength levels while considering factors such as cost and carbon *** role of seawater in enhancing short-term strength through crystal formation is noteworthy and can be advantageous for certain *** conclusion,this research demonstrates the potential of using a powdered shell-based curing agent for solidifying dredged soil in an environmentally friendly and cost-effective *** recommended ratios for different str

关键词： carbon reduction and solidification dredged soil abandoned shells orthogonal test chemical additives(lime and cement) unconfined compressive strength(UCS)

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