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Distributing Characteristics of the Charge on the Bomb Body with Capacitance Fuze
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作者 邓甲昊 詹毅 施聚生 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期291-295,共5页
For establishing the equation of the capacitive target detection accurately, the distributing characteristics of the charges on the bomb body with capacitance fuze were explored. Continuous charges were analyzed disp... For establishing the equation of the capacitive target detection accurately, the distributing characteristics of the charges on the bomb body with capacitance fuze were explored. Continuous charges were analyzed dispersively. Based on the Coulomb's law, the dynamic equilibrium equations of the inducing charges on the bomb body were set up. For the four cases of d 0/L (the ratio between the electrode distance and the bomb length), the curves of the charge's distribution were given. It was concluded that: ① the charge density decreases steadily from the end near the frontal electrode to the bomb tail; ② the declining rate of the density is governed by d 0/L , the larger the value of d 0/L ,the higher the declining rate, and vice versa. 展开更多
关键词 proximity fuze capacitance fuze target detection distribution characteristic of charge
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Establishment and implementation of a spoke-like service network for collecting and distributing blood
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《中国输血杂志》 CAS CSCD 2001年第S1期356-,共1页
关键词 Establishment and implementation of a spoke-like service network for collecting and distributing blood
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Measurement and study of the distributing law of in-situ stresses in rock mass at great depth 被引量:4
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作者 Zhuoying Tan Meifeng Cai 《Journal of University of Science and Technology Beijing》 CSCD 2006年第3期207-212,共6页
To solve the technical cruxes of the conventional system in deep rock mass, an automatic testing system for hydraulic fracturing that includes a single tube for hydraulic loop, a pressure-relief valve, central-tubeles... To solve the technical cruxes of the conventional system in deep rock mass, an automatic testing system for hydraulic fracturing that includes a single tube for hydraulic loop, a pressure-relief valve, central-tubeless packers, and a multichannel real-time data acquisition system was used for in-situ stresses measurement at great depths (over 1000 m) in a coalfield in Juye of Northern China. The values and orientations of horizontal principal stresses were determined by the new system. The virgin stress field and its distributing law were decided by the linear regression from the logged 37 points in seven boreholes. Besides, the typical boreholes arranged in both the adjacent zone and far away zone of the faults were analyzed, respectively. The results show that a stress concentration phenomenon and a deflection in the orientation of the maximal horizontal stress exist in the adjacent zone of the faults, which further provides theoretical basis for design and optimization of mining. 展开更多
关键词 rock mass at great depth earth stress hydraulic fracturing in-situ stress distribution
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A DNA-Programmed Cargo Distributing System in Living Cells
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作者 Yuhan Wei Yueyue Feng +7 位作者 Xiaoliang Chen Wenhe Ma Kaizhe Wang Qian Li Jiang Li Lihua Wang Chunhai Fan Ying Zhu 《CCS Chemistry》 2025年第2期452-459,共8页
The functionalization of living cells,both internally and externally,transforming them into microma-chines with specified functions,holds significant po-tential in fields such as biosensing,biocomputing,and intelligen... The functionalization of living cells,both internally and externally,transforming them into microma-chines with specified functions,holds significant po-tential in fields such as biosensing,biocomputing,and intelligent theranostics.However,due to the complexity and dynamic nature of living cells,it remains challenging to allocate exogenous function-al materials to specific locations within the cell or on its surface and maintain their positions stable for a reasonable period.Here,we devise a DNA-pro-grammed cargo distributing system(DCD),capable of distributing functional modules to the cell mem-brane or within the cell as needed.This system includes an amphiphilic DNA structure for determin-ing the destination of the cargo and a DNA connector carried on it for recognizing the DNA-encoded cargo.We test three different morphologies of amphiphilic DNA structures and find that their efficiencies in cell surface retention and cell internalization significantly varied,enabling the distribution of nanoparticle cargos on the cell membrane and within the cell in distinct proportions.Their positions can remain sta-ble for at least 6 h.Moreover,this allocation method shows specificity,which minimizes the deployment of mismatched cargo.This method provides new tools for the modular construction of cellular micro-machines. 展开更多
关键词 living cells MICROMACHINE DNA nano-technology amphiphilic DNA structures cargo distribution
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基于深度学习算法的湿法冶金资源回收效率提升方法设计及研究
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作者 宋玉安 赵伟 《湿法冶金》 北大核心 2025年第1期125-131,共7页
为进一步提高湿法冶金资源回收率,解决资源回收流程控制的智能化、自动化控制程度不高的问题,提出了一种采用Transformer模型进行金属浸出率预测,再采用Distributional Q-function改进DQN模型进行湿法冶金金浸出率最大化的湿法冶金流程... 为进一步提高湿法冶金资源回收率,解决资源回收流程控制的智能化、自动化控制程度不高的问题,提出了一种采用Transformer模型进行金属浸出率预测,再采用Distributional Q-function改进DQN模型进行湿法冶金金浸出率最大化的湿法冶金流程控制方法。结果表明:该系统控制方法能有效提升湿法冶金过程中金属浸出率的预测准确率;基于Distributional Q-function改进DQN模型能有效降低资源回收率最大化模型的迭代计算时间。该法能有效提高某工厂湿法冶金资源回收率。 展开更多
关键词 Transformer模型 最优化 Distributional Q-function DQN模型 资源回收
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Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles 被引量:1
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作者 Yanting Liu Wei Huang +8 位作者 Jiayi Wen Xin Xiong Ting Xu Qi Wang Xiusheng Chen Xianxian Zhao Shihua Li Xiaojiang Li Weili Yang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1124-1134,共11页
The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin a... The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin are expressed in mammalian brains.This has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small animals.Understanding this issue is critical for elucidating the in vivo roles of PINK1 and Parkin.Recently,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate brain.In the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate brain.We found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey brains.PINK1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable distribution.Immunofluorescent double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial stress.These findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage. 展开更多
关键词 NEURODEGENERATION PARKIN Parkinson’s disease PINK1 subcellular distribution
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Coordinated Control Strategy of New Energy Power Generation System with Hybrid Energy Storage Unit 被引量:1
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作者 Yun Zhang Zifen Han +2 位作者 Biao Tian Ning Chen Yi Fan 《Energy Engineering》 EI 2025年第1期167-184,共18页
The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,... The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,photovoltaic power generation is unstable and random,resulting in a low utilization rate and directly affecting the stability of the power grid.To solve this problem,this paper proposes a coordinated control strategy for a newenergy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage unit.Firstly,the variational mode decomposition algorithm is used to separate the high and low frequencies of the power signal,which is conducive to the rapid and accurate suppression of the power fluctuation of the energy storage system.Secondly,the fuzzy control algorithm is introduced to balance the power between energy storage.In this paper,the actual data is used for simulation,and the simulation results show that the strategy realizes the effective suppression of the bus voltage fluctuation and the accurate control of the internal state of the energy storage unit,effectively avoiding problems such as overshoot and over-discharge,and can significantly improve the stability of the photovoltaic power generation systemand the stability of the Direct Current bus.It is of great significance to promote the development of collaborative control technology for photovoltaic hybrid energy storage units. 展开更多
关键词 Photovoltaic power suppression hybrid energy storage unit variationalmodal decomposition fuzzy control power distribution control
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Coupling and Spatial Disparities of Regional Economy and Ecosystem in High-Quality Town Development 被引量:2
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作者 Xinyi Ren Xiaowen Tan +2 位作者 Dan Luo Rongxin Lu Chien-Chi Chu 《Research in Ecology》 2025年第1期15-29,共15页
This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expan... This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expansion with environmental protection,a comprehensive evaluation index system is constructed,encompassing two key dimensions:regional economy and ecological environment.Using panel data from 2013 to 2022,the coupling coordination degree model is employed to quantify the interactions and synergy between these dimensions.Additionally,spatial econometric methods are applied to calculate both global and local Moran’s Index,revealing spatial clustering patterns,regional disparities,and heterogeneity.The relative development model further identifies critical factors influencing regional coordination,with a focus on the lagging development of basic infrastructure and public services.The findings demonstrate a positive temporal trend toward improved regional coordination and reduced development gaps,with a spatial pattern characterized by higher coupling degrees in eastern and central regions compared to western areas.Based on these results,this study proposes actionable strategies to enhance coordinated development,emphasizing ecological conservation,the establishment of green production and consumption systems,ecological restoration,and strengthened municipal collaboration.This revised abstract emphasizes the study’s purpose,methods,and key findings more clearly while maintaining a professional and concise tone.Finally,based on the above analysis results,the corresponding coordinated development suggestions of regional economy and ecological environment are given from the aspects of ecological environment protection measures,green production and consumption system construction,ecological environment restoration and municipal coordination. 展开更多
关键词 Regional Economies Ecological Environment Coupling Coordination Degree Spatiotemporal Distribution Characteristics Relative Development Model
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Properties and structure investigation of the friction stir welding seam of the AA6061-T6 plates 被引量:2
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作者 M.Soukieh W.Harara +2 位作者 H.Koudaimi M.Halak M.Kassem 《China Welding》 2025年第2期132-138,共7页
Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW sea... Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW seams of AA6061-T6 plates were made us-ing different FSW parameters.The structure of the FSW seams was investigated using X-ray diffraction(XRD),scanning electron mi-croscope(SEM)and non destructive testing(NDT)techniques and their hardness was also measured.The dominated phase in the AA6061-T6 alloy and the FSW seams was theα-Al.The FSW seam had lower content of the secondary phases than the AA6061-T6 al-loy.The hardness of the FSW seams was decreased by about 30%compared to the AA6061-T6 alloy.The temperature distributions in the weld seams were also studied experimentally and numerically modeled and the results were in a good agreement. 展开更多
关键词 AA6061-T6 Friction stir welding welding parameters temperature distribution numerical modeling FSW weld seam
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Data driven prediction of fragment velocity distribution under explosive loading conditions 被引量:2
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作者 Donghwan Noh Piemaan Fazily +4 位作者 Songwon Seo Jaekun Lee Seungjae Seo Hoon Huh Jeong Whan Yoon 《Defence Technology(防务技术)》 2025年第1期109-119,共11页
This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key de... This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key design parameters including casing dimensions and detonation positions.The paper details the finite element analysis for fragmentation,the characterizations of the dynamic hardening and fracture models,the generation of comprehensive datasets,and the training of the ANN model.The results show the influence of casing dimensions on fragment velocity distributions,with the tendencies indicating increased resultant velocity with reduced thickness,increased length and diameter.The model's predictive capability is demonstrated through the accurate predictions for both training and testing datasets,showing its potential for the real-time prediction of fragmentation performance. 展开更多
关键词 Data driven prediction Dynamic fracture model Dynamic hardening model FRAGMENTATION Fragment velocity distribution High strain rate Machine learning
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Development of a coupled model to simulate and assess arsenic contamination and impact factors in the Jinsha River Basin,China 被引量:1
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作者 Yidian Sun Xu Zhang +5 位作者 Hong Peng Wenting Zhou Anna Jiang Feng Zhou Hao Wang Wanshun Zhang 《Journal of Environmental Sciences》 2025年第1期50-61,共12页
With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the pr... With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the precise control strategies.Taking the industrialintensive Jinsha River Basin as typical area,a two-dimensional hydrodynamic water quality model coupled with Soil andWater Assessment Tool(SWAT)model was developed to accurately simulate the watershed-scale distribution and transport of As in the terrestrial and aquatic environment at high spatial and temporal resolution.The effects of hydro-climate change,hydropower station construction and non-point source emissions on Aswere quantified based on the coupled model.The result indicated that higher As concentration areas mainly centralized in urban districts and concentration slowly decreased from upstream to downstream.Due to the enhanced rainfall,the As concentration was significantly higher during the rainy season than the dry season.Hydro-climate change and the construction of hydropower station not only affected the dissolved As concentration,but also affected the adsorption and desorption of As in sediment.Furthermore,As concentration increased with the input of non-point source pollution,with the maximum increase about 30%,resulting that non-point sources contributed important pollutant impacts to waterways.The coupled model used in pollutant behavior analysis is generalwith high potential application to predict and mitigate water pollution. 展开更多
关键词 Watershed system ARSENIC Modeling DISTRIBUTION Hydro-climate change Non-point source pollution
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A Trusted Distributed Oracle Scheme Based on Share Recovery Threshold Signature 被引量:1
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作者 Shihao Wang Xuehui Du +4 位作者 Xiangyu Wu Qiantao Yang Wenjuan Wang Yu Cao Aodi Liu 《Computers, Materials & Continua》 2025年第2期3355-3379,共25页
With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become ... With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become a research hotspot, and the security of the oracle responsible for providing reliable data has attracted much attention. The most widely used centralized oracles in blockchain, such as Provable and Town Crier, all rely on a single oracle to obtain data, which suffers from a single point of failure and limits the large-scale development of blockchain. To this end, the distributed oracle scheme is put forward, but the existing distributed oracle schemes such as Chainlink and Augur generally have low execution efficiency and high communication overhead, which leads to their poor applicability. To solve the above problems, this paper proposes a trusted distributed oracle scheme based on a share recovery threshold signature. First, a data verification method of distributed oracles is designed based on threshold signature. By aggregating the signatures of oracles, data from different data sources can be mutually verified, leading to a more efficient data verification and aggregation process. Then, a credibility-based cluster head election algorithm is designed, which reduces the communication overhead by clarifying the function distribution and building a hierarchical structure. Considering the good performance of the BLS threshold signature in large-scale applications, this paper combines it with distributed oracle technology and proposes a BLS threshold signature algorithm that supports share recovery in distributed oracles. The share recovery mechanism enables the proposed scheme to solve the key loss issue, and the setting of the threshold value enables the proposed scheme to complete signature aggregation with only a threshold number of oracles, making the scheme more robust. Finally, experimental results indicate that, by using the threshold signature technology and the cluster head election algorithm, our scheme effectively improves the execution efficiency of oracles and solves the problem of a single point of failure, leading to higher scalability and robustness. 展开更多
关键词 Blockchain threshold signature distributed oracle data submission share recovery
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Effects of micro-sprinkler irrigation and topsoil compaction on winter wheat grain yield and water use efficiency in the Huaibei Plain, China 被引量:1
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作者 Jinpeng Li Siqi Wang +6 位作者 Zhongwei Li Kaiyi Xing Xuefeng Tao Zhimin Wang Yinghua Zhang Chunsheng Yao Jincai Li 《Journal of Integrative Agriculture》 2025年第8期2974-2988,共15页
Increasing the grain yield(GY) and water use efficiency(WUE) of winter wheat in the Huaibei Plain(HP), China are essential. However, the effects of micro-sprinkler irrigation and topsoil compaction after wheat seed so... Increasing the grain yield(GY) and water use efficiency(WUE) of winter wheat in the Huaibei Plain(HP), China are essential. However, the effects of micro-sprinkler irrigation and topsoil compaction after wheat seed sowing on the GY and WUE are unclear. Therefore, a two-year field experiment was conducted during the 2021–2023 winter wheat growing seasons with a total six treatments: rain-fed(RF), conventional irrigation(CI) and micro-sprinkler irrigation(MI), as well as topsoil compaction after seed sowing under these three irrigation methods(RFC, CIC, and MIC). The results in the two years indicated that MI significantly increased GY compared to CI and RF, by averages of 17.9 and 42.1%, respectively. The increase in GY of MI was due to its significant increases in the number of spikes, kernels per spike, and grain weight. The chlorophyll concentration in flag leaves of MI after the anthesis stage maintained higher levels than with CI and RF, and was the lowest in RF. This was due to the dramatically enhanced catalase and peroxidase activities and lower malondialdehyde content under MI. Compared with RF and CI, MI significantly promoted dry matter remobilization and production after anthesis, as well as its contribution to GY. In addition, MI significantly boosted root growth, and root activity during the grain-filling stage was remarkably enhanced compared to CI and RF. In 2021–2022, there was no significant difference in WUE between MI and RF, but the WUE of RF was significantly lower than that of MI in 2022–2023. However, the WUE in MI was significantly improved compared to CI, and it increased by averages of 15.1 and 17.6% for the two years. Topsoil compaction significantly increased GY and WUE under rain-fed conditions due to improved spike numbers and dry matter production. Overall, topsoil compaction is advisable for enhancing GY and WUE in rain-fed conditions, whereas micro-sprinkler irrigation can be adopted to simultaneously achieve high GY and WUE in the HP. 展开更多
关键词 winter wheat MICRO-SPRINKLER grain yield root distribution water utilization
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Cement-mortar lining failure and metal release caused by electrochemical corrosion of ductile iron pipes in drinking water distribution systems 被引量:1
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作者 Hao Guo Rui Wang +5 位作者 Menghan Jiang Yimei Tian Yapeng Jin Weigao Zhao Chenwan Wang Jianhua Yin 《Journal of Environmental Sciences》 2025年第6期488-502,共15页
The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality d... The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality deterioration and posing a risk to public health.An in-situ scanning vibrating electrode technique(SVET)with micron-scale resolution,microscopic scale detection and water quality analysis were used to investigate the corrosion behavior and metal release from DPs throughout the whole CML failure process.Metal pollutants release occurred at three different stages of CML failure process,and there are potential risks of water quality deterioration exceeding the maximum allowable levels set by national standards in the partial failure stage and lining peeling stage.Furthermore,the effects of water chemistry(Cl^(−),SO_(4)^(2−),NO_(3)−,and Ca^(2+))on corrosion scale growth and iron release activity,were investigated during the CML partial failure stage.Results showed that the CML failure process in DPs was accelerated by the autocatalysis of localized corrosion.Cl^(−)was found to damage the uncorroded metal surface,while SO_(4)^(2−)mainly dissolved the corrosion scale surface,increasing iron release.Both the oxidation of NO_(3)−and selective sedimentation of Ca2+were found to enhance the stability of corrosion scales and inhibit iron release. 展开更多
关键词 Water distribution system Cement mortar lining Corrosion Metal release SVET
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Long-term spatiotemporal variations of ammonia in the Yangtze River Delta region of China and its driving factors 被引量:1
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作者 Jingkai Xue Chengzhi Xing +6 位作者 Qihua Li Shanshan Wang Qihou Hu Yizhi Zhu Ting Liu Chengxin Zhang Cheng Liu 《Journal of Environmental Sciences》 2025年第4期202-217,共16页
This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to 2020.Utilizing data fr... This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to 2020.Utilizing data from the Infrared Atmospheric Sounding Interfer-ometer(IASI),Generalized Additive Models(GAM),and the GEOS-Chem chemical transport model,we observed a significant increase of NH_(3)VCDs in the YRD between 2014 and 2020.The spatial distribution analysis revealed higher NH_(3)concentrations in the northern part of the YRD region,primarily due to lower precipitation,alkaline soil,and intensive agricul-tural activities.NH_(3)VCDs in the YRD region increased significantly(65.18%)from 2008 to 2020.The highest growth rate occurs in the summer,with an annual average growth rate of 7.2%during the period from 2014 to 2020.Agricultural emissions dominated NH_(3)VCDs during spring and summer,with high concentrations primarily located in the agricultural areas adjacent to densely populated urban zones.Regions within several large urban areas have been discovered to exhibit relatively stable variations in NH_(3)VCDs.The rise in NH_(3)VCDs within the YRD region was primarily driven by the reduction of acidic gases like SO_(2),as emphasized by GAM modeling and sensitivity tests using the GEOS-Chem model.The concentration changes of acidic gases contribute to over 80%of the interannual variations in NH_(3)VCDs.This emphasizes the crucial role of environmental policies targeting the reduction of these acidic gases.Effective emission control is urgent tomitigate environmental hazards and secondary particulate matter,especially in the northern YRD. 展开更多
关键词 Yangtze River Delta AMMONIA Spatiotemporal distribution Driving factors
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Study on cook-off characteristics and thermal safety venting area of RBOE charge 被引量:1
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作者 Kebin Zhang Wenbin Li +3 位作者 Changfang Zhao Zhifang Wei Shuxia Zhang Jin Li 《Defence Technology(防务技术)》 2025年第1期271-287,共17页
RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the warhead.Based on the thermal decomp... RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the warhead.Based on the thermal decomposition reaction characteristics and combustion characteristics of each component of RBOE explosive,the cook-off calculation models of RBOE warhead before and after ignition were established.In addition,closed and vented warheads were designed,as well as fast and slow cook-off test devices.The cook-off characteristics and thermal safety venting area of RBOE warhead were extensively studied.The results showed that the closed RBOE warhead underwent deflagration reaction under both slow and fast cook-off conditions.The calculation result of the shell wall temperature before slow cookoff ignition response of the warhead was 454.06 K,with an error of+1.75%compared to the test result of462.15 K,and the temperature rise rate calculated was in good agreement with the test.The calculated ignition time of RBOE warhead under fast cook-off was 161 s,with an error of+8.8%compared to the test result of 148 s,which verified the accuracy of cook-off model of RBOE warhead before ignition.According to the cook-off calculation model of the warhead after ignition and cook-off test of the vented warhead,it was determined that the thermal safety venting area was 1124.61 mm^(2)for fast cook-off and 530.66 mm~2 for slow cook-off,effectively preventing the reaction of warhead above combustion.Therefore,this study provides a scientific basis for the thermal safety design and evaluation of insensitive warheads. 展开更多
关键词 RBOE explosive Cook-off model Temperature distribution Pressure growth Venting area
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Revealing the intrinsic connection between residual strain distribution and dissolution mode in Mg-Sc-Y-Ag anode for Mg-air battery 被引量:1
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作者 Wei-li Cheng Xu-bang Hao +4 位作者 Jin-hui Wang Hui Yu Li-fei Wang Ze-qin Cui Cheng Chang 《Journal of Magnesium and Alloys》 2025年第3期1020-1033,共14页
The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconci... The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconcile this contradiction,two Mg-0.1Sc-0.1Y-0.1Ag anodes with different residual strain distribution through extrusion with/without annealing are fabricated.The results indicate that annealing can significantly lessen the“pseudo-anode”regions,thereby changing the dissolution mode of the matrix and achieving an effective dissolution during discharge.Additionally,p-type semiconductor characteristic of discharge productfilm could suppress the self-corrosion reaction without reducing the polarization of anode.The magnesium-air battery utilizing annealed Mg-0.1Sc-0.1Y-0.1Ag as anode achieves a synergistic improvement in specific capacity(1388.89 mA h g^(-1))and energy density(1960.42 mW h g^(-1)).This anode modification method accelerates the advancement of high efficiency and long lifespan magnesium-air batteries,offering renewable and cost-effective energy solutions for electronics and emergency equipment. 展开更多
关键词 Mg-air batteries ANODE Residual strain distribution Dissolution mode Discharge mechanism
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Spatial-temporal distribution and emission of urban scale air pollutants in Hefei based on Mobile-DOAS 被引量:1
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作者 Zhidong Zhang Pinhua Xie +8 位作者 Ang Li Min Qin Jin Xu Zhaokun Hu Xin Tian Feng Hu Yinsheng Lv Jiangyi Zheng Youtao Li 《Journal of Environmental Sciences》 2025年第5期238-251,共14页
As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limite... As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limited research in recent years on the spatial-temporal distribution and emission of its atmospheric pollutants.To address this,this study conducted mobile observations of urban roads using the Mobile-DOAS instrument from June 2021 to May 2022.The monitoring results exhibit a favourable consistent with TROPOMI satellite data and ground monitoring station data.Temporally,there were pronounced seasonal variations in air pollutants.Spatially,high concentration of HCHO and NO_(2)were closely associated with traffic congestion on roadways,while heightened SO_(2)levels were attributed to winter heating and industrial emissions.The study also revealed that with the implementation of road policies,the average vehicle speed increased by 95.4%,while the NO concentration decreased by 54.4%.In the estimation of urban NO_(x)emission flux,it was observed that in temporal terms,compared with inventory data,the emissions calculated viamobile measurements exhibitedmore distinct seasonal patterns,with the highest emission rate of 349 g/sec in winter and the lowest of 142 g/sec in summer.In spatial terms,the significant difference in emissions between the inner and outer ring roads also suggests the presence of the city’s primary NO_(x)emission sources in the area between these two rings.This study offers data support for formulating the next phase of air pollution control measures in urban areas. 展开更多
关键词 Mobile-DOAS HCHO NO_(2) SO_(2) Spatial-temporal distribution NOx emission
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Impact of coking plant to heavy metal characteristics in groundwater of surrounding areas:Spatial distribution,source apportionment and risk assessments 被引量:1
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作者 Congqing Wang Wanjun Wang +5 位作者 ChaoWang Shixing Ren Yingjun Wu Meicheng Wen Guiying Li Taicheng An 《Journal of Environmental Sciences》 2025年第3期688-698,共11页
Coking industry is a potential source of heavy metals(HMs)pollution.However,its impacts to the groundwater of surrounding residential areas have not been well understood.This study investigated the pollution character... Coking industry is a potential source of heavy metals(HMs)pollution.However,its impacts to the groundwater of surrounding residential areas have not been well understood.This study investigated the pollution characteristics and health risks of HMs in groundwater nearby a typical coking plant.Nine HMs including Fe,Zn,Mo,As,Cu,Ni,Cr,Pb and Cd were analyzed.The average concentration of total HMswas higher in the nearby area(244.27μg/L)than that of remote area away the coking plant(89.15μg/L).The spatial distribution of pollution indices including heavy metal pollution index(HPI),Nemerow index(NI)and contamination degree(CD),all demonstrated higher values at the nearby residential areas,suggesting coking activity could significantly impact the HMs distribution characteristics.Four sources of HMs were identified by Positive Matrix Factorization(PMF)model,which indicated coal washing and coking emission were the dominant sources,accounted for 40.4%,and 31.0%,respectively.Oral ingestionwas found to be the dominant exposure pathway with higher exposure dose to children than adults.Hazard quotient(HQ)values were below 1.0,suggesting negligible non-carcinogenic health risks,while potential carcinogenic risks were from Pb and Ni with cancer risk(CR)values>10−6.Monte Carlo simulation matched well with the calculated results with HMs concentrations to be the most sensitive parameters.This study provides insights into understanding how the industrial coking activities can impact the HMs pollution characteristics in groundwater,thus facilitating the implement of HMs regulation in coking industries. 展开更多
关键词 Coking industry Heavy metal GROUNDWATER Spatial distribution Source apportionment Monte Carlo simulation
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