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Journal of Environmental Sciences 2025年第3期149卷 585-597页

作者： Ke Yu Yifan Song Jin Lin Shen Qu School of Management and Economics Beijing Institute of TechnologyBeijing 100081China Center for Energy&Environmental Policy research Beijing Institute of TechnologyBeijing 100081China

Urban areas’performance in water,energy,infrastructure,and socio-economic sectors is intertwined and measurable through Sustainable Development Goals(SDGs)6–*** synergy among these is critical for *** study constructs an indicator framework that reflects progress towards these urban SDGs in *** indicate underperformance in SDGs 8–11,suggesting the need for transformative *** network analysis,the research reveals complementarities among these ***,the SDG space divides into socio-economic and ecological clusters,with SDG 6(Clean Water and Sanitation)central to ***,SDG 8(Decent Work and Economic Growth)and SDG 9(Industry,Innovation,and Infrastructure)act as bridges,while greater synergies exist between SDG 12(Responsible Consumption and Production)and SDG 13(Climate Action).An in-depth view at the indicator-level shows a core-periphery structure,emphasizing indicators like SDG 6.2(Wastewater Treatment Rate)and SDG 6.6(Recycled Water Production Capacity per capita)as *** study confirms the urban SDG space’s stability and predictiveness,underscoring its value in steering well-aligned policy decisions for sustainable growth.

关键词： Sustainable development goals Synergy Urban development Policy decisions

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni_(2)P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin Peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced research institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： B-doped atoms P vacancies Nickel phosphide Bidirectional sulfur conversion Lithium-sulfur batteries

Status analysis on sputtering and erosion evaluation methods of ion optic systems

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Chinese Journal of Aeronautics 2025年第1期38卷 254-270页

作者： Long MIAO Tongxun YANG Zhengxi ZHU Chang LU Zhiwen WU Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Advanced Aerospace Power and Energy research Center Beijing Institute of TechnologyZhuhai 519088China

In the past few decades,ion engines have been widely used in deep-space propulsion and satellite *** aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion *** one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming *** this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid *** advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are *** different types of experimental methods of grid assembly erosion patterns are *** analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid ***,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime.

关键词： Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation

Smoke and NO_(x)emission characteristics of in-use construction machinery base on substantial field measurement:A case study in beijing,China

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Journal of Environmental Sciences 2025年第3期149卷 386-393页

作者： Huawei Yi Yangyang Cui Lijun Zhu Yan Shen Han Li Guanghan Huang Linzhen Qu Dongdong Guo Lei Nie Yifeng Xue National Engineering research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China beijing Vehicle Emission Management Affairs Centre Beijing 100176China

To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in beijing,we selected 905 construction machines in beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration *** investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the *** results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance *** observed amongmachinery types,with low-power engine forklifts showing higher smoke *** NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively *** rated net power had the most significant impact on NO_(x)***,NO_(x)emissions from construction machinery need further ***,we found a weak negative correlation(pbeijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.

关键词： Fuel-oil construction machinery Smoke NO_(x) Emission level Regulatory suggestion

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu Run Hou Chenghao Wu Ruishan Xie Shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing research institute of beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

High-energy-density lithium manganese iron phosphate for lithium-ion batteries:Progresses,challenges,and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang Yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China research institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Hong Kong 9977China institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMn_(x)Fe_(1-x)PO_(4)has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMn_(x)Fe_(1-x)PO_(4)to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMn_(x)Fe_(1-x)PO_(4),including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMn_(x)Fe_(1-x)PO_(4)materials,to achieve practical energy storage requirements.

关键词： Lithiummanganese iron phosphate High energydensity Lithium-ionbatteries Reactionmechanism Tap density

Detection in Optical Remote Sensing Images of Transmission Tower Based on Oriented Object Detection

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CSEE Journal of Power and Energy Systems 2025年第1期11卷 217-226页

作者： Yuanpeng Tan Fei Jiao Wenhao Mo Haiying Liu Xiaojing Bai Jiaxiu Ma China Electric Power research institute Beijing 100192China China Electric Power research institute and North China Electric Power University Beijing100192China China Electric Power research institute and State Grid Corporation of China Information and Communication Branch Beijing100192China

Transmission towers play a crucial role in overhead transmission line systems and are the key target of transmission line *** the help of remote sensing technology,transmission towers can be effectively detected in wide areas at reasonable costs and in a relatively short time ***,it is difficult to identify the type of transmission towers in optical remote sensing images due to detail degradation caused by long-distance and high-altitude *** paper proposes a transmission tower detection method in optical remote sensing images using an oriented object detector and object and shadow joint *** enrich the information,the transmission towers and their shadows are jointly detected through a CenterNet detector with an orientation prediction *** improve the detection accuracy of difficult objects,attention and deformable convolutional network modules are introduced to the backbone and orientation prediction branches,*** the orientation and the aspect ratio of the objects and shadows,a focal loss function with an aspect ratio is employed to further improve the *** and shadow joint detection are separately realized through the one-box and multi-box detection strategies.A transmission tower dataset RSITT labeled with horizontal and oriented boxes is *** conducted on the RSITT dataset have demonstrated that the detection accuracy and recall rate of the proposed joint detection algorithm reached 73.2%and 95.2%.

关键词： Oriented object detection remote sensing image transmission projection transmission tower detection

Perspectives on additive manufacturing for warhead applications

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Defence Technology(防务技术) 2025年第1期43卷 225-251页

作者： Hao Xue Qiang Zhou Chuan Xiao Guangyan Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Ordnance Science and research Academy of China Beijing 100089China beijing institute of Technology Chongqing Innovation Center Chongqing 401120China

According to different damage modes,warheads are roughly divided into three types:fragmentation warheads,shaped charge warheads,and penetrating *** to limitations in material and structural manufacturing,traditional manufacturing methods make it difficult to fully utilize the damage ability of the *** manufacturing(AM)technology can fabricate complex structures,with classified materials composition and customized components,while achieving low cost,high accuracy,and rapid production of the *** maturity of AM technology has brought about a new round of revolution in the field of *** this paper,we first review the principles,classifications,and characteristics of different AM *** development trends of AM technologies are pointed out,including multi-material AM technology,hybrid AM technology,and smart AM *** our survey,PBF,DED,and EBM technologies are mainly used to manufacture warhead damage *** and DIW technologies are mainly used to manufacture warhead ***,the research on the application of AM technology in three types of warhead and warhead charges was reviewed and the existing problems and progress of AM technologies in each warhead were ***,we summarized the typical applications and look forward to the application prospects of AM technology in the field of warheads.

关键词： Additive manufacturing Fragmentation warhead Shaped charge warhead Penetrating warhead Warhead charge

Origin and Evolution Process of Overpressure in the Shahezi Formation of Xujiaweizi Fault Depression in the Northern Songliao Basin,NE China

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Acta Geologica Sinica(English Edition) 2025年第1期99卷 212-227页

作者： ZHANG Chengju JIANG Zhenxue LU Jiamin SHI Lidong BI Zhongyu SUN Lidong YANG Liang LI Xiaomei LIU Jiajun MIAO Huan National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China Unconventional Petroleum research institute China University of Petroleum(Beijing)Beijing 102249China Exploration and Development research institute of PetroChina Daqing Oilfield Company Limited DaqingHeilongjiang 163712China

It is of great significance for deep oil and gas exploration to understand the origin and evolution behind *** occurs in the deep Shahezi Formation of Xujiaweizi fault ***,due to limited degree of exploration,there are some problems in the study area,such as unclear understanding of the origin of overpressure and the vague investigation of overpressure *** clarify the impact of overpressure on oil and gas migration and accumulation in the study area,this study focuses on the research of the origin and evolution of overpressure in the Shahezi Formation of the study area,utilizing single well logging parameters and combining methods such as microthermometry of fluid inclusions,laser Raman spectrum,and basin *** results show that the overpressure of the Shahezi Formation in Xujiaweizi fault depression is primarily generated by hydrocarbon generation pressurization,and the evolution of overpressure is closely related to hydrocarbon *** development of overpressure can be divided into two evolutionary stages:early hydrocarbon generation pressurization and late uplift release,with slight variations in different *** glutenite gas reservoirs in the Shahezi Formation are characterized by continuous *** overall charging period ranges from the late Denglouku to the early Mingshui(110-67 Ma ago).There is an obvious paleo-overpressure during the gas reservoir formation *** gas generation period of source rocks occurred approximately 125-60 Ma ago,and the main gas generation period(112-67 Ma ago)highly coincides with the period of natural gas *** anomalously high pressure during the accumulation period is considered the significant driving force for natural gas *** addition,the sustained effect of overpressure provides better conditions for the preservation of tight gas reservoirs within the *** results of the study are of guiding significance for the in-depth expl

关键词： fluid inclusion laser Raman spectrum basin simulation overpressure genesis paleo-pressure recovery Shahezi Formation Xujiaweizi fault depression

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi LU institute of Ecological Conservation and Restoration Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China institute of Desertification Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China institute of Great Green Wall Bayan Nur015200China Satellite Application Centre for Ecology and Environment MEEBeijing100094China institute of Microelectronics Chinese Academy of SciencesBeijing100029China Aerospace Information research institute Chinese Academy of SciencesBeijing100094China institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution(VHR)unmanned aerial vehicle(UAV)and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover(FWVC)and fractional herbaceous vegetation cover(FHVC)in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error(RMSE)values for the FWVC and FHVC models were 10.69%and 11.67%,and the R^(2)values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10^(6)*** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy Land a

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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