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氧诱导条件下自发性视网膜色素变性模型rdf小鼠视网膜新生血管相关生长因子的表达和相互作用
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作者 刘梦园 谷蒙 +1 位作者 赵婧钰 张迁 《眼科新进展》 北大核心 2026年第1期13-17,共5页
目的探讨氧诱导条件下自发性视网膜色素变性模型rdf小鼠视网膜新生血管相关生长因子的表达和相互作用。方法选取7天龄C57BL/6J和rdf两种品系的小鼠各42只。将每种品系的小鼠分别随机分为常氧组与高氧组,分为4组:C57BL/6J常氧组、C57BL/6... 目的探讨氧诱导条件下自发性视网膜色素变性模型rdf小鼠视网膜新生血管相关生长因子的表达和相互作用。方法选取7天龄C57BL/6J和rdf两种品系的小鼠各42只。将每种品系的小鼠分别随机分为常氧组与高氧组,分为4组:C57BL/6J常氧组、C57BL/6J高氧组、rdf常氧组及rdf高氧组,每组18只;两种品系各预留6只(共12只)小鼠用于后续视网膜原代微血管内皮细胞的提取。利用高氧环境诱导建立视网膜病变模型作为高氧组小鼠,常氧组小鼠在正常大气环境中饲养。HE染色观察小鼠视网膜的结构变化,Western blot检测小鼠视网膜血管内皮生长因子(VEGF)、色素上皮衍生因子(PEDF)、缺氧诱导因子-1α及促红细胞生成素蛋白的表达,免疫共沉淀分析小鼠视网膜组织中PEDF与VEGF蛋白互作关系,免疫荧光染色分析不同品系小鼠原代视网膜内皮细胞中VEGF与PEDF的表达情况。结果HE染色结果显示,C57BL/6J常氧组小鼠视网膜各层结构排列整齐,未见新生血管内皮细胞突破内界膜;C57BL/6J高氧组小鼠视网膜结构紊乱,可见较多新生血管内皮细胞突破内界膜。rdf常氧组与高氧组小鼠视网膜各层结构均基本保持整齐,仅高氧组偶见新生血管内皮细胞突破内界膜。Western blot分析结果表明,无论在常氧还是高氧环境中,与C57BL/6J组相比,rdf组小鼠视网膜组织中促血管生成因子(VEGF、促红细胞生成素、缺氧诱导因子-1α)蛋白表达水平均显著降低;而血管抑制因子PEDF蛋白表达水平显著升高,差异均有统计学意义(均为P<0.05)。免疫共沉淀实验结果表明,促血管生成因子VEGF与血管抑制因子PEDF在小鼠视网膜组织中存在相互作用。免疫荧光染色结果显示,PEDF与VEGF在C57BL/6J与rdf小鼠的原代视网膜内皮细胞中均存在共定位。C57BL/6J常氧组原代视网膜内皮细胞VEGF/PEDF光密度比值为4.55±1.35,C57BL/6J高氧组为26.39±7.58,rdf常氧组为0.52±0.38,rdf高氧组为1.76±0.46,各组间比较差异均有统计学意义(均为P<0.05)。结论在视网膜色素变性rdf小鼠视网膜中,VEGF/PEDF平衡向抗血管生成方向显著偏移,小鼠视网膜促血管生成因子低表达与抗血管生成因子高表达共同抑制了氧诱导后病理性新生血管的形成。 展开更多
关键词 视网膜新生血管 氧诱导视网膜病变 血管内皮生长因子 色素上皮衍生因子 rdf小鼠
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Joint Optimization of Routing and Resource Allocation in Decentralized UAV Networks Based on DDQN and GNN
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作者 Nawaf Q.H.Othman YANG Qinghai JIANG Xinpei 《电讯技术》 北大核心 2026年第1期1-10,共10页
Optimizing routing and resource allocation in decentralized unmanned aerial vehicle(UAV)networks remains challenging due to interference and rapidly changing topologies.The authors introduce a novel framework combinin... Optimizing routing and resource allocation in decentralized unmanned aerial vehicle(UAV)networks remains challenging due to interference and rapidly changing topologies.The authors introduce a novel framework combining double deep Q-networks(DDQNs)and graph neural networks(GNNs)for joint routing and resource allocation.The framework uses GNNs to model the network topology and DDQNs to adaptively control routing and resource allocation,addressing interference and improving network performance.Simulation results show that the proposed approach outperforms traditional methods such as Closest-to-Destination(c2Dst),Max-SINR(mSINR),and Multi-Layer Perceptron(MLP)-based models,achieving approximately 23.5% improvement in throughput,50% increase in connection probability,and 17.6% reduction in number of hops,demonstrating its effectiveness in dynamic UAV networks. 展开更多
关键词 decentralized UAV network resource allocation routing algorithm GNN DDQN DRL
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MWaOA:A Bio-Inspired Metaheuristic Algorithm for Resource Allocation in Internet of Things
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作者 Rekha Phadke Abdul Lateef Haroon Phulara Shaik +3 位作者 Dayanidhi Mohapatra Doaa Sami Khafaga Eman Abdullah Aldakheel N.Sathyanarayana 《Computers, Materials & Continua》 2026年第2期1285-1310,共26页
Recently,the Internet of Things(IoT)technology has been utilized in a wide range of services and applications which significantly transforms digital ecosystems through seamless interconnectivity between various smart ... Recently,the Internet of Things(IoT)technology has been utilized in a wide range of services and applications which significantly transforms digital ecosystems through seamless interconnectivity between various smart devices.Furthermore,the IoT plays a key role in multiple domains,including industrial automation,smart homes,and intelligent transportation systems.However,an increasing number of connected devices presents significant challenges related to efficient resource allocation and system responsiveness.To address these issue,this research proposes a Modified Walrus Optimization Algorithm(MWaOA)for effective resource management in smart IoT systems.In the proposed MWaOA,a crowding process is incorporated to maintain diversity and avoid premature convergence thereby enhancing the global search capability.During resource allocation,the MWaOA prevents early convergence,which aids in achieving a better balance between the exploration and exploitation phases during optimization.Empirical evaluations show that the MWaOA reduces energy consumption by approximately 4% to 34%and minimizes the response time by 6% to 33% across different service arrival rates.Compared to traditional optimization algorithms,MWaOA reduces energy consumption by 5% to 30%and minimizes the response time by 4% to 28% across different simulation epochs.The proposed MWaOA provides adaptive and robust resource allocation,thereby minimizing transmission cost while considering network constraints and real-time performance parameters. 展开更多
关键词 Delay GATEWAY internet of things resource allocation resource management walrus optimization algorithm
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Flexible resource allocation for power systems to maximize diversified values in resilience,carbon reduction and renewable energy consumption
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作者 Zhaohong Bie Yiheng Bian Chenxing Yang 《iEnergy》 2026年第1期43-54,共12页
The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource a... The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource allocation model to determine the type,number and location of flexible resources to increase the values of resilience,carbon reduction and renewable energy consumption.To evaluate the values of resilience,a restoration model for transmission systems is established that considers the coordination of fossil-fuel generators,energy storage systems(ESSs)and renewable energy generators in building restoration paths.The collaborative power-carbon-tradable green certificate(TGC)market model is then applied to evaluate the resource values in terms of carbon reduction and renewable energy consumption.Finally,the model is formulated as a mixed-integer linear programming(MILP)with a nonconvex feasible domain,and the normalized normal constraint(NNC)method is applied to obtain approximate Pareto frontiers for decision makers.Case studies validate the effectiveness of the proposed model in improving multi-factor values and analyze the impact of resource regulation capacity on values of restoration and carbon reduction. 展开更多
关键词 Multi-objective planning Power system Carbon reduction RESILIENCE Flexible resource
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Research on the Optimal Allocation of Community Elderly Care Service Resources Based on Big Data Technology
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作者 Shuying Li 《Journal of Clinical and Nursing Research》 2026年第1期241-246,共6页
With the accelerating aging process of China’s population,the demand for community elderly care services has shown diversified and personalized characteristics.However,problems such as insufficient total care service... With the accelerating aging process of China’s population,the demand for community elderly care services has shown diversified and personalized characteristics.However,problems such as insufficient total care service resources,uneven distribution,and prominent supply-demand contradictions have seriously affected service quality.Big data technology,with core advantages including data collection,analysis and mining,and accurate prediction,provides a new solution for the allocation of community elderly care service resources.This paper systematically studies the application value of big data technology in the allocation of community elderly care service resources from three aspects:resource allocation efficiency,service accuracy,and management intelligence.Combined with practical needs,it proposes optimal allocation strategies such as building a big data analysis platform and accurately grasping the elderly’s care needs,striving to provide operable path references for the construction of community elderly care service systems,promoting the early realization of the elderly care service goal of“adequate support and proper care for the elderly”,and boosting the high-quality development of China’s elderly care service industry. 展开更多
关键词 Big data technology COMMUNITY Elderly care Service resources
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Occurrence modes and comprehensive utilization of critical metal resources associated with coal:A review
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作者 Qin Zhang Wei Cheng +6 位作者 Tiebin Zhang Hongbo Liu Jiwei Yuan Aoao Chen Tingshun Wang Qian Liu Jianghe Wang 《International Journal of Mining Science and Technology》 2026年第2期277-293,共17页
Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a syste... Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources. 展开更多
关键词 Coal-associated resources Lithium GALLIUM GERMANIUM Rare carth elements Extraction and separation
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Research on Vehicle Joint Radar Communication Resource Optimization Method Based on GNN-DRL
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作者 Zeyu Chen Jian Sun +1 位作者 Zhengda Huan Ziyi Zhang 《Computers, Materials & Continua》 2026年第2期1430-1446,共17页
To address the issues of poor adaptability in resource allocation and low multi-agent cooperation efficiency in Joint Radar and Communication(JRC)systems under dynamic environments,an intelligent optimization framewor... To address the issues of poor adaptability in resource allocation and low multi-agent cooperation efficiency in Joint Radar and Communication(JRC)systems under dynamic environments,an intelligent optimization framework integrating Deep Reinforcement Learning(DRL)and Graph Neural Network(GNN)is proposed.This framework models resource allocation as a Partially Observable Markov Game(POMG),designs a weighted reward function to balance radar and communication efficiencies,adopts the Multi-Agent Proximal Policy Optimization(MAPPO)framework,and integrates Graph Convolutional Networks(GCN)and Graph Sample and Aggregate(Graph-SAGE)to optimize information interaction.Simulations show that,compared with traditional methods and pure DRL methods,the proposed framework achieves improvements in performance metrics such as communication success rate,Average Age of Information(AoI),and policy convergence speed,effectively enabling resource management in complex environments.Moreover,the proposed GNN-DRL-based intelligent optimization framework obtains significantly better performance for resource management in multi-agent JRC systems than traditional methods and pure DRL methods. 展开更多
关键词 Graph neural network joint radar and communication resource allocation multi-agent collaboration
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Dynamic Resource Allocation for Multi-Priority Requests Based on Deep Reinforcement Learning in Elastic Optical Network
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作者 Zhou Yang Yang Xin +1 位作者 Sun Qiang Yang Zhuojia 《China Communications》 2026年第2期312-327,共16页
As the types of traffic requests increase,the elastic optical network(EON)is considered as a promising architecture to carry multiple types of traffic requests simultaneously,including immediate reservation(IR)and adv... As the types of traffic requests increase,the elastic optical network(EON)is considered as a promising architecture to carry multiple types of traffic requests simultaneously,including immediate reservation(IR)and advance reservation(AR).Various resource allocation schemes for IR/AR requests have been designed in EON to reduce bandwidth blocking probability(BBP).However,these schemes do not consider different transmission requirements of IR requests and cannot maintain a low BBP for high-priority requests.In this paper,multi-priority is considered in the hybrid IR/AR request scenario.We modify the asynchronous advantage actor critic(A3C)model and propose an A3C-assisted priority resource allocation(APRA)algorithm.The APRA integrates priority and transmission quality of IR requests to design the A3C reward function,then dynamically allocates dedicated resources for different IR requests according to the time-varying requirements.By maximizing the reward,the transmission quality of IR requests can be matched with the priority,and lower BBP for high-priority IR requests can be ensured.Simulation results show that the APRA reduces the BBP of high-priority IR requests from 0.0341 to0.0138,and the overall network operation gain is improved by 883 compared to the scheme without considering the priority. 展开更多
关键词 deep reinforcement learning dynamic resource allocation elastic optical network multipriority requests
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Turning Black Waste into a Green Resource
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作者 LIU JING 《China Today》 2026年第1期68-70,共3页
To deal with a polluted by-product of coal production,central China’s Shanxi Province has explored a governance path that addresses both the symptoms and root causes.
关键词 black waste green resource polluted product shanxi province coal production governance path
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Water resources and sustainable management in Tajikistan under global change
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作者 CHEN Yaning FANG Gonghuan +5 位作者 LI Zhi ZHANG Xueqi LI Weihong Nekruz GULAHMADOV Farhod NASRULLOEV Aminjon GULAKHMADOV 《Regional Sustainability》 2026年第1期1-10,共10页
As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-govern... As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-government water resource management,and inefficient water use.Existing research has predominantly focused on individual hydrological processes,such as glacier retreat,snow cover change,or transboundary water issues,but it has yet to fully capture the overall complexity of water system.Tajikistan’s water system functions as an integrated whole from mountain runoff to downstream supply,but a comprehensive study of its water resource has yet to be conducted.To address this research gap,this study systematically examined the status,challenges,and sustainable management strategies of Tajikistan’s water resources based on a literature review,remote sensing data analysis,and case studies.Despite Tajikistan’s relative abundance of water resources,global warming is accelerating glacier melting and altering the hydrological cycles,which have resulted in unstable runoff patterns and heightened risks of extreme events.In Tajikistan,outdated infrastructure and poor management are primary causes of low water-use efficiency in the agricultural sector,which accounts for 85.00%of the total water withdrawals.At the governance level,Tajikistan faces challenges in balancing the water-energy-food nexus and transboundary water resource issues.To address these issues,this study proposes core paths for Tajikistan to achieve sustainable water resource management,such as accelerating technological innovation,promoting water-saving agricultural technologies,improving water resource utilization efficiency,and establishing a community participation-based comprehensive management framework.Additionally,strengthening cross-border cooperation and improving real-time monitoring systems have been identified as critical steps to advance sustainable water resource utilization and evidence-based decision-making in Tajikistan and across Central Asia. 展开更多
关键词 Climate change Glacial retreat Cross-border cooperation Water resource management TAJIKISTAN Central Asia
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AI and ML in groundwater exploration and water resources management:Concepts,methods,applications,and future directions
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作者 Adla Andalu MGopal Naik Sandeep Budde 《Journal of Groundwater Science and Engineering》 2026年第1期100-122,共23页
The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This rev... The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This review explores key AI and ML concepts,methodologies,and their applications in hydrology,focusing on groundwater potential mapping,water quality prediction,and groundwater level forecasting.It discusses various data acquisition techniques,including remote sensing,geospatial analysis,and geophysical surveys,alongside preprocessing methods that are essential for enhancing model accuracy.The study highlights AI-driven solutions in water distribution,allocation optimization,and realtime resource management.Despite their advantages,the application of AI and ML in water sciences faces several challenges,including data scarcity,model reliability,and the integration of these tools with traditional water management systems.Ethical and regulatory concerns also demand careful consideration.The paper also outlines future research directions,emphasizing the need for improved data collection,interpretable models,real-time monitoring capabilities,and interdisciplinary collaboration.By leveraging AI and ML advancements,the water sector can enhance decision-making,optimize resource distribution,and support the development of sustainable water management strategies. 展开更多
关键词 Artificial intelligence Machine learning Groundwater exploration Hydrological modeling Remote sensing applications Water resources management
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Intelligent Resource Allocation for Multiaccess Edge Computing in 5G Ultra-Dense Slicing Network Using Federated Multiagent DDPG Algorithm
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作者 Gong Yu Gong Pengwei +3 位作者 Jiang He Xie Wen Wang Chenxi Xu Peijun 《China Communications》 2026年第1期273-289,共17页
Nowadays,advances in communication technology and cloud computing have spawned a variety of smart mobile devices,which will generate a great amount of computing-intensive businesses,and require corresponding resources... Nowadays,advances in communication technology and cloud computing have spawned a variety of smart mobile devices,which will generate a great amount of computing-intensive businesses,and require corresponding resources of computation and communication.Multiaccess edge computing(MEC)can offload computing-intensive tasks to the nearby edge servers,which alleviates the pressure of devices.Ultra-dense network(UDN)can provide effective spectrum resources by deploying a large number of micro base stations.Furthermore,network slicing can support various applications in different communication scenarios.Therefore,this paper integrates the ultra-dense network slicing and the MEC technology,and introduces a hybrid computing offloading strategy in order to satisfy various quality of service(QoS)of edge devices.In order to dynamically allocate limited resources,the above problem is formulated as multiagent distributed deep reinforcement learning(DRL),which will achieve low overhead computation offloading strategy and real-time resource allocation decisions.In this context,federated learning is added to train DRL agents in a distributed manner,where each agent is dedicated to exploring actions composed of offloading decisions and allocating resources,so as to jointly optimize system delay and energy consumption.Simulation results show that the proposed learning algorithm has better performance compared with other strategies in literature. 展开更多
关键词 federated learning multiaccess edge computing mutiagent deep reinforcement learning resource allocation ultra-dense slicing network
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Optimal competitive resource assignment in two-stage Colonel Blotto game with Lanchester-type attrition
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作者 YUAN Weilin CHEN Shaofei +4 位作者 HU Zhenzhen JI Xiang LU Lina SU Xiaolong CHEN Jing 《Journal of Systems Engineering and Electronics》 2026年第1期242-256,共15页
In strategic decision-making tasks,determining how to assign limited costly resource towards the defender and the attacker is a central problem.However,it is hard for pre-allocated resource assignment to adapt to dyna... In strategic decision-making tasks,determining how to assign limited costly resource towards the defender and the attacker is a central problem.However,it is hard for pre-allocated resource assignment to adapt to dynamic fighting scenarios,and exists situations where the scenario and rule of the Colonel Blotto(CB)game are too restrictive in real world.To address these issues,a support stage is added as supplementary for pre-allocated results,in which a novel two-stage competitive resource assignment problem is formulated based on CB game and stochastic Lanchester equation(SLE).Further,the force attrition in these two stages is formulated as a stochastic progress to consider the complex fighting progress,including the case that the player with fewer resources defeats the player with more resources and wins the battlefield.For solving this two-stage resource assignment problem,nested solving and no-regret learning are proposed to search the optimal resource assignment strategies.Numerical experiments are taken to analyze the effectiveness of the proposed model and study the assignment strategies in various cases. 展开更多
关键词 resource assignment Colonel Blotto(CB)game stochastic Lanchester equation(SLE) regret match
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The pathway to discovering antiviral drugs from marine resources
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作者 Wei Wang 《Infectious Diseases Research》 2026年第1期1-3,共3页
Owing to the emergence of drug resistance and high morbidity,the need for novel antiviral drugs with novel targets is highly sought after.Marine-derived compounds mostly possess potent antiviral activity and serve as ... Owing to the emergence of drug resistance and high morbidity,the need for novel antiviral drugs with novel targets is highly sought after.Marine-derived compounds mostly possess potent antiviral activity and serve as a primary source for developing novel antiviral drugs,making the rapid discovery and evaluation of marine antiviral agents particularly crucial.Thus,future research should place greater emphasis on the identification of novel antiviral targets through the combination of artificial intelligence(AI)and structural pharmacology,as well as expanding the marine resource and target databases. 展开更多
关键词 identification novel antiviral targets discovery evaluation antiviral drugs artificial intelligence ai drug resistance developing novel antiviral drugsmaking marine resources marine antiviral agents
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Mineral resources of Asia continent:Resource endowment,mining industry pattern,and contributions to the world economy
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作者 Xi-feng Chen Gang Wang +2 位作者 Yan-xiong Mei Hai-jie Zhao Yan-yun Ma 《China Geology》 2026年第1期1-24,共24页
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral... Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation. 展开更多
关键词 Mineral resource endowment Minerogenetic series Metallogenic specialization Carbonate-type REE deposits Weathering-type REE deposits Hard rock-type lithium deposits Laterite nickel deposits Crystalline graphite deposits Magmatic nickel deposits Significant metallogenic belt Mining industry development pattern Mineral exploration and exploitation World economy Contribution Asia continent
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Overview of in-situ oxygen production technologies for lunar resources 被引量:2
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作者 Youpeng Xu Sheng Pang +5 位作者 Liangwei Cong Guoyu Qian Dong Wang Laishi Li Yusheng Wu Zhi Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期233-255,共23页
The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extract... The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives. 展开更多
关键词 lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis
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RDF技术在固体废物处理中的应用 被引量:1
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作者 金晶 王清森 +4 位作者 郑伟 王庆 冯旭 朱光鼒 王殿二 《绿色科技》 2025年第6期171-174,213,共5页
为探讨RDF技术在国内外固体废物处理中的应用现状,分析了制约其推广的关键因素,并提出了改进措施,以促进RDF技术的广泛应用,助力实现“双碳”目标。通过文献综述、案例分析等方法,详细阐述了RDF技术在生活垃圾、陈腐垃圾、一般工业固废... 为探讨RDF技术在国内外固体废物处理中的应用现状,分析了制约其推广的关键因素,并提出了改进措施,以促进RDF技术的广泛应用,助力实现“双碳”目标。通过文献综述、案例分析等方法,详细阐述了RDF技术在生活垃圾、陈腐垃圾、一般工业固废和园林废弃物处理中的应用进展,深入剖析了阻碍RDF技术推广的原因,包括标准体系不完善、制备成本高、缺乏投资补贴、环保排放问题以及经济效益不佳等。结果表明:国内RDF技术起步较晚,但近年来在生活垃圾、一般工业固废和园林废弃物处理方面取得了一定进展。 展开更多
关键词 rdf技术 固废处理 改进建议
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基于HINT的时态RDF语义索引和查询研究
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作者 张航 刘宇 《计算机与数字工程》 2025年第12期3477-3483,共7页
鉴于时态信息是知识图谱中的重要属性,研究人员已提出了多种高效存储和查询时态RDF的方案。然而,现有的时态RDF的存储和查询未能充分利用三元组之间的时态语义关系,从而会影响面向时态RDF的语义查询性能。针对上述问题,提出了基于区间索... 鉴于时态信息是知识图谱中的重要属性,研究人员已提出了多种高效存储和查询时态RDF的方案。然而,现有的时态RDF的存储和查询未能充分利用三元组之间的时态语义关系,从而会影响面向时态RDF的语义查询性能。针对上述问题,提出了基于区间索引HINT的时态RDF索引结构,该索引结构融合了HINT的层次索引和RDF的组合位图索引,从而使索引结构能蕴含三元组之间的时态语义关系。在HINT和组合位图索引的基础上,实现了面向SPARQL的时态算子,能够支持十三种Allen时态关系的语义查询。实验结果表明,基于HINT的时态RDF语义索引能够提升时态RDF的查询性能。 展开更多
关键词 知识图谱 时态rdf 两层索引 时态语义 查询优化
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面向双时态RDF星型查询的两阶段索引方法
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作者 王刚 张薇 +1 位作者 陈宏栉 张富 《东北大学学报(自然科学版)》 北大核心 2025年第2期18-27,共10页
为了对时间信息进行表示和处理,随之开展了时态RDF(temporal resource description framework)的扩展研究,而如何对时态RDF数据进行有效的管理也逐渐成为了一个重要问题.构建有效的索引机制是管理时态RDF数据和提高查询效率的重要途径之... 为了对时间信息进行表示和处理,随之开展了时态RDF(temporal resource description framework)的扩展研究,而如何对时态RDF数据进行有效的管理也逐渐成为了一个重要问题.构建有效的索引机制是管理时态RDF数据和提高查询效率的重要途径之一.本文提出了一种针对双时态RDF(bitemporal RDF)星型查询的两阶段索引方法:第一阶段索引提出一种基于双时态RDF节点邻域信息的候选集生成方法,第二阶段索引进一步提出一种基于位图索引的结果集生成方法.通过两阶段索引可以避免星型查询中成本昂贵的连接操作,快速得到查询结果.在查询效率和索引性能方面进行了对比实验,验证了所提方法的有效性. 展开更多
关键词 资源描述框架(rdf) 双时态rdf 星型查询 两阶段索引 位图索引
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Current status and diversity of fish resources in the Pinglu Canal Century Project 被引量:1
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu Canal Project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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