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中南祁连西段余石山铌钽矿成矿过程元素地球化学指标研究及意义

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大地构造与成矿学 2024年第3期48卷 637-653页

作者：吴义布余君鹏褚广博司豪佳司东泽曹晓峰甘肃省地质调查院甘肃兰州730000 兰州大学地质科学与矿产资源学院甘肃兰州730000 中国地质大学(武汉)资源学院湖北武汉430074

中南祁连西段余石山铌钽矿是近年在国内发现的变粒岩型铌钽矿床,规模已达大型,是一种新的铌钽矿床类型,但对变粒岩中铌钽富集成矿过程中元素地球化学变化尚未开展系统研究。本文通过详细的野外调查和室内综合分析,系统研究了余石山矿区... 详细信息

中南祁连西段余石山铌钽矿是近年在国内发现的变粒岩型铌钽矿床,规模已达大型,是一种新的铌钽矿床类型,但对变粒岩中铌钽富集成矿过程中元素地球化学变化尚未开展系统研究。本文通过详细的野外调查和室内综合分析,系统研究了余石山矿区无铌钽矿化变粒岩、含铌钽变粒岩、铌钽矿化体、低品位铌钽矿石、铌钽工业矿石等5类铌钽矿化程度不同变粒岩的元素地球化学特征,结果显示变粒岩型铌钽矿Nb富集成矿过程中Si、Al、Zr、Hf、REE等元素存在规律性变化,总结了成矿过程中有效元素地球化学指标,发现变粒岩中Nb含量与原岩岩石类型关系密切,揭示该矿床经历了新元古代岩浆成矿作用和加里东期热液变质成矿作用,共两期三阶段成矿过程,该研究为中南祁连西段铌钽矿找矿和成矿研究提供了依据。

关键词：余石山铌钽矿元素地球化学指标成矿作用成矿过程

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均匀化制度对6014铝合金显微组织的影响

金属热处理 2024年第1期49卷 215-222页

作者：迟蕊李延成孟双徐志远于俊芃张德镇郭丰佳孙宁山东南山铝业股份有限公司国家铝合金压力加工工程技术研究中心山东烟台265700 山东南山铝业股份有限公司有色金属产业研究院山东烟台265700

借助光学显微镜的明暗场像、差示扫描量热法、扫描电镜及透射电镜等手段,研究了不同均匀化制度对6014铝合金的组织、富铁相转变、元素分布和弥散相均匀性的影响。结果表明,6014铝合金铸锭中存在枝晶偏析现象和非平衡共晶组织,合金元素... 详细信息

借助光学显微镜的明暗场像、差示扫描量热法、扫描电镜及透射电镜等手段,研究了不同均匀化制度对6014铝合金的组织、富铁相转变、元素分布和弥散相均匀性的影响。结果表明,6014铝合金铸锭中存在枝晶偏析现象和非平衡共晶组织,合金元素含量波动较大,晶粒为等轴晶。铸锭中的第二相含量明显高于单级和双级均匀化态,由于第二相形态和分布不同,可分为α-AlFeMnSi、β-AlFeSi、Mg_(2)Si和Q-AlCuMgSi相。采用560℃×4 h+540℃×6 h双级均匀化处理制度时,网状枝晶并未全部断裂,延长560℃一级均匀化保温时间至12 h时,较多的β-AlFeSi相转变为α-AlFeMnSi相。采用560℃×19 h单级均匀化处理时,枝晶基本由网状形态转变为链状形态。采用580℃×4 h+540℃×6 h双级均匀化制度时,弥散相α-AlFeMnSi分布较为均匀,延长580℃一级均匀化保温时间至12 h时,组织发生过烧,弥散相尺寸增大且在晶界周围富集。

关键词： 6014铝合金均匀化制度组织弥散相均匀性

甘肃西秦岭地区重要金矿预测模型的建立及资源潜力预测

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西北地质 2024年第5期57卷 88-105页

作者：张家瑞高永伟张忠平谢建强杨彦余超余君鹏李通国贾志磊王晓伟甘肃省地质调查院甘肃兰州730030 甘肃省自然资源厅甘肃兰州730030 甘肃省矿产资源储量评审中心甘肃兰州730030 甘肃省地质矿产勘查开发局甘肃兰州730030

为满足当前形势下甘肃西秦岭地区金矿勘查开发与战略部署的要求,在甘肃省金矿资源潜力动态评价成果的基础上,总结了甘肃西秦岭地区金矿资源特征、预测模型及资源潜力,初步提出西秦岭地区金矿勘查工作部署建议。西秦岭岩金矿产地有223处... 详细信息

为满足当前形势下甘肃西秦岭地区金矿勘查开发与战略部署的要求,在甘肃省金矿资源潜力动态评价成果的基础上,总结了甘肃西秦岭地区金矿资源特征、预测模型及资源潜力,初步提出西秦岭地区金矿勘查工作部署建议。西秦岭岩金矿产地有223处,燕山期为主要成矿期。分布于甘肃南部的陇南、天水、甘南地区,矿床类型以岩浆热液型、浅成中-低温热液型矿床为主,在此基础上,修正了李坝、大桥、阳山典型矿床预测模型,建立了早子沟、加甘滩、寨上、小东沟等4个典型矿床预测模型。采用矿床模型综合地质信息预测方法,应用MRAS软件,圈定预测区179处,运用体积法,估算金矿预测量3512.107 t。相较甘肃省矿产资源潜力评价成果(2013年),预测区增加了18处,预测量增加了461.03 t,新增主要分布于以地南、小东沟-天子坪一带等重点找矿地段,预测成果将为甘肃西秦岭地区金矿勘查工作部署提供科学依据。

关键词：金矿资源特征预测要素预测模型资源潜力甘肃西秦岭

A New Type of Rare Metal Deposit:The yushishan Leptynite-Type Nb-Ta Deposit in Eastern Altun,Gansu Province,NW China

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Acta Geologica Sinica(English Edition) 2022年第5期96卷 1471-1483页

作者： JIANG SHAOYONG LIU TAO ZHANG HAOXIANG CAO SHUyuN ZHENG RUOHONG LI TONGGUO yu junpeng WU YIBU State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral ResourcesSchool of Earth ResourceChina University of GeosciencesWuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China Geological Survey of Gansu Province Lanzhou 730020China

The yusishan deposit is a newly found leptynite-type niobium and tantalum(Nb-Ta)deposit,which is located in the Eastern Altun of Gansu *** leptynite of the Neoproterozoic Aoyougou Formation occurs more than 10 km long and 3 km *** this paper,we carried out a detailed study of the leptynite and related *** U-Pb dating of zircon reveals ages of 831±5 Ma and 790±5 Ma for the unmineralized leptynite and 491±4 Ma and 455±4 Ma for the mineralized *** petrographic and geochemical evidence identified the protolith of the leptynite as alkalin e volcanic rocks that erupted during Neoproterozoic at ca.830 *** ca.490 Ma,the tectono-magmatic and metamorphic event triggered remobilization and enrichment of Nb-Ta as well as other critical metals(REE,Zr,Hf etc)with the formation of industry orebodies in the leptynite *** yushishan deposit presents many similarities with the alkaline volcanic rocks related rare metal deposits in the south Qinling of China and the Brochman,Toogni and Southern Peak Range deposits in *** therefore propose that the yushishan deposit is a new type(sub-type)of Nb-Ta deposit and termed as leptynite type that represents the metamorphic counterpart of the alkaline volcanic rocks related rare metal deposits.

关键词： Nb-Ta deposit Leptynite alkaline volcanic rock metamorphism yushishan

A Practical Reinforcement Learning Framework for Automatic Radar Detection

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中兴通讯技术:英文版 2023年第3期21卷 22-28页

作者： yu junpeng CHEN Yiyu Nanjing Research Institute of Electronics Technology Nanjing 210039China Nanjing University Nanjing 210023China

At present,the parameters of radar detection rely heavily on manual adjustment and empirical knowledge,resulting in low *** manual adjustment methods cannot meet the requirements of modern radars for high efficiency,high precision,and high ***,it is necessary to explore a new intelligent radar control learning framework and technology to improve the capability and automation of radar *** learning is popular in decision task learning,but the shortage of samples in radar control tasks makes it difficult to meet the requirements of reinforcement *** address the above issues,we propose a practical radar operation reinforcement learning framework,and integrate offline reinforcement learning and meta-reinforcement learning methods to alleviate the sample requirements of reinforcement *** results show that our method can automatically perform as humans in radar detection with real-world settings,thereby promoting the practical application of reinforcement learning in radar operation.

关键词： meta-reinforcement learning radar detection reinforcement learning offline reinforcement learning

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西秦岭洛大式菱铁矿矿床的基本成矿要素

地质论评 2024年第S1期70卷 115-117页

作者：何进忠刘涛何甘地余君鹏何海军牛鹏飞朱永新吴义布吴保祥甘肃省地质调查院兰州730000 兰州大学地质科学与矿产资源学院兰州730000 中国科学院西北生态环境资源研究院兰州730000

洛大式菱铁矿分布于甘肃南秦岭成矿带,由翠古山铁矿、绿坝铁矿、洛大铁矿、查居铁矿和柴马山铁矿等小型矿床组成;主要矿石矿物为菱铁矿,其次为黄铁矿和赤铁矿;矿床成因类型一直被认为是沉积型或沉积改造型(1)。考虑大型矿床的发现往往... 详细信息

洛大式菱铁矿分布于甘肃南秦岭成矿带,由翠古山铁矿、绿坝铁矿、洛大铁矿、查居铁矿和柴马山铁矿等小型矿床组成;主要矿石矿物为菱铁矿,其次为黄铁矿和赤铁矿;矿床成因类型一直被认为是沉积型或沉积改造型(1)。考虑大型矿床的发现往往源于对中小型矿床的研究(Richards,2013).

关键词：菱铁矿成矿过程含矿建造浅成中—低温热液型矿床西秦岭

Adapitive waveform design for distributed OFDM MIMO radar system in multi-target scenario

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Chinese Journal of Aeronautics 2018年第3期31卷 567-574页

作者： Haitao WANG junpeng yu Wenzhen yu De BEN Nanjing Research Institute of Electronics Teehnology Nanjing 210039 China

In order to improve detection and estimation performance of distributed OrthogonalFrequency-Division Multiplexing（OFDM） Multiple-Input Multiple-Output（MIMO） radar system in multi-target scene, we propose a novel approach of Adaptive Waveform Design（AWD） based on a constrained Multi-Objective Optimization（MOO）. The sparse measurement model of this radar system is derived, and the method based on decomposed Dantzig selectors is applied for the sparse recovery according to the block structures of the sparse vector and the system matrix. An AWD approach is proposed, which optimizes two objective functions, namely minimizing the upper bound of the recovery error and maximizing the weakest-target return, by adjusting the complex weights of the emitting waveform amplitudes. Several numerical simulations are provided and their results show that the detection and estimation performance of the radar system is improved significantly when this MOO-based AWD approach is applied to the distributed OFDM MIMO radar system. Especially, we verify the effectiveness of our AWD approach when the available samples are reduced severally and the technique of compressed sensing is introduced.

关键词： Adaptive waveform design Compressed sensing Distributed radar Multi-objective optimization Multiple-input multipleoutput Orthogonal-frequencydivision multiplexing

热轧工艺对6014铝合金显微组织和织构的影响

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上海金属 2024年第5期46卷 41-46页

作者：李延成迟蕊李涛于俊芃徐志远杨立民刘洋山东南山铝业股份有限公司国家铝合金压力加工工程技术研究中心山东烟台265700

采用金相显微镜、电子背散射衍射仪、扫描电子显微镜、透射电子显微镜等,研究了热轧工艺对6014铝合金显微组织和织构的影响。结果表明:4卷热轧6014铝合金板表层均发生了再结晶。D20卷板中心存在2 cm厚的再结晶层,再结晶体积分数为55.41%... 详细信息

采用金相显微镜、电子背散射衍射仪、扫描电子显微镜、透射电子显微镜等,研究了热轧工艺对6014铝合金显微组织和织构的影响。结果表明:4卷热轧6014铝合金板表层均发生了再结晶。D20卷板中心存在2 cm厚的再结晶层,再结晶体积分数为55.41%,这与其粗轧道次多、压下量大、中间坯待温时间长以及卷取温度较高有关。D40卷板的热轧Cube织构体积分数最高,冷轧加工率相对较低,制耳平衡性较差,容易导致板材翻边不合格。D10、D20和D30卷板中Q相分布在晶界,呈长条状,与晶界约呈45°角。D40卷板晶界分布着Si相。

关键词： 6014铝合金热轧织构第二相翻边

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M-FCN based sea-surface weak target detection

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1111-1118页

作者： PAN Meiyan SUN Jun YANG yuhao LI Dasheng yu junpeng The 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210039China Key Laboratory of IntelliSense Technology China Electronics Technology Group CorporationNanjing 210039China

This paper focuses on the sea-surface weak target detection based on memory-fully convolutional network(M-FCN)in strong sea ***,the constant false alarm rate(CFAR)detection method utilizes a low threshold with high probability of false alarm to detect sea-surface weak targets after non-coherent *** the detection threshold can generate a large number of false alarms while increasing the detection rate,and how to suppress a large number of false alarms is the key to improve the performance of weak target ***,the detection result of the low threshold is operated to construct the target matrix suitable for the size of fully convolutional networks and the convolution operator ***,the M-FCN architecture is designed to learn the different accumulation characteristics of the target and the sea clutter between different *** improving the detection performance,the historical multi-frame information is memorized by the network,and the end-to-end structure is established to detect sea-surface weak target *** results on measured data demonstrate that the M-FCN method outperforms the traditional track before detection(TBD)method and reduces false alarm tracks by 35.1%,which greatly improves the track quality.

关键词： sea-surface weak target detection memory-fully convolutional network(M-FCN) multi-frame information end-to-end