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地球学报 2024年第2期45卷 266-266页

作者：陈伟刘青枰

西藏鑫龙金矿钻探现场及矿石特征。创新应用斑岩-浅成低温热液成矿理论,集成遥感高光谱、化探和物探技等术方法手段,首次在西藏陆相火山区发现了高硫化浅成低温热液型金矿-鑫龙金矿,且成矿潜力大(主矿体视厚度达55 m,真厚度约10.5m,平...

西藏鑫龙金矿钻探现场及矿石特征。创新应用斑岩-浅成低温热液成矿理论,集成遥感高光谱、化探和物探技等术方法手段,首次在西藏陆相火山区发现了高硫化浅成低温热液型金矿-鑫龙金矿,且成矿潜力大(主矿体视厚度达55 m,真厚度约10.5m,平均品位17.97 g/t)。鑫龙金矿的发现为西藏乃至全国陆相火山岩区浅成低温热液型金矿找矿开启了新的篇章。这项由中国地质科学院矿产资源研究所唐菊兴院士团队完成的研究成果,

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Fatigue Crack Growth in Cold-Rolled and Annealed Polycrystalline Superelastic NiTi Alloys

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Acta Mechanica Solida Sinica 2018年第5期31卷 599-607页

作者： Junyu chen Hao Yin Guozheng Kang qingping Sun School of Civil Engineering Wuhan University Wuhan 430072 China State Key Laboratory-of Traction Powerl Southwest Jiaotong University Chengdu 610031 China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Kowloon Hong Kong China

The fatigue crack growth in cold-rolled （CR） and annealed （AN） polycrystalline superelastic NiTi shape memory alloys under cyclic stressing are investigated. The fatigue crack growth morphologies of compact tension specimens are recorded. Experimental results show that the main cracks of the AN specimens grow along the original crack plane, while the crack paths of the CR specimens orient at 18° angle to the original horizontal crack plane. The latter is due to the strong anisotropy of elastic modulus and hardness after the cold rolling. Besides, the fatigue crack growth rates of the AN specimens in the regime of △K = 4 MPa√m-9 MPa√m are lower than those of the CR ones. The AN specimens have higher fatigue crack growth resistance than the CR specimens due to the stronger shielding mechanism caused by plastic deformation and reduced anisotropy by annealing.

关键词： Fatigue crack growth NiTi Anisotropy Shielding mechanism

Bioinspired Multi-Metal Structures Produced via Direct Ink Writing

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Journal of Bionic Engineering 2022年第6期19卷 1578-1588页

作者： Chao Xu Xiang chen Wenzheng Wu qingping Liu Luquan Ren Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130000China Weihai Institute of Bionics Jilin UniversityWeihai264400China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130000China

Bioinspired Multi-Metal Structures(MMSs)combine distinct properties of multiple materials,benefiting from improved properties and providing superior *** Manufacturing(AM)exhibits enormous advantages in applying different materials and geometries according to the desired functions at specific locations of the structure,having great potential in fabricating multi-materials ***,current AM techniques have difficulty manufacturing 3D MMSs without material cross-contamination flexibly and *** study demonstrates a reliable,fast,and flexible direct ink writing method to fabricate 3D *** in-situ material-switching system enables the deposition of multiple metallic materials across different layers and within the same layer.3D Fe-Cu MMSs with complex geometries and fine details are fabricated as proof of *** microstructures,chemical and phase compositions,and tensile fracture surfaces of the Fe-Cu interfaces indicate a well-bonded interface without cracks,delamination,or material *** envision this novel method making other metallic combinations and even metal-ceramic *** paves the way for manufacturing 3D MMSs using AM and establishes the possibilities of numerous MMSs applications in engineering fields.

关键词： Bioinspired Bionic Multi-metal structure(MMS) Direct ink writing(DIW)Additive manufacturing(AM)

An improved model for predicting hydrate phase equilibrium in marine sediment environment

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Journal of Natural Gas Chemistry 2010年第3期19卷 241-245页

作者： Yongchen Song Mingjun Yang Yongjun chen qingping Li Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of Technology Dalian 116024 Liaoning China CNOOC Research Center Beijing 100027 China

Based on the models of hydrate phase equilibrium in bulk water and porous media,an improved model was proposed to predict the methane hydrate equilibrium in marine sediment *** the suggested model,mechanical equilibrium of force between the interfaces in hydrate-liquid-vapor system was *** electrolyte was present in pore water,interfacial energy between hydrate and liquid was corrected by an equation that is expressed as the function of temperature and electrolyte *** activity of water is calculated based on the Pitzer model and the interfacial energy between liquid and gas is solved using the Li *** prediction results show good agreement with the experimental *** comparison with other models,it is proved that this model can improve the accuracy for predicting hydrate phase equilibrium in marine sediment environment.

关键词： hydrate equilibrium interfacial energy marine sediment

Performance analysis of multi-group three-tuple cross-eye jamming

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Journal of Systems Engineering and Electronics 2022年第1期33卷 80-90页

作者： chen Jiabei SHI Qingzhan HUANG Zhaoyu WANG qingping YUAN Naichang State Key Laboratory of Complex Electromagnetic Environmental Effects of Electronics and Information System National University of Defense TechnologyChangsha 410000China

Monopulse radar is widely used in *** monopulse radar has always been a research hotspot in electronic warfare(EW).Cross-eye jamming has always been considered as the most effective measures to jam with monopulse *** this paper, we propose a multi-group three-tuple crosseye jamming structure where each group contains three antenna elements with a definite phase and an amplitude ***, based on the principle of monopulse angle measurement, the error angle is deduced *** show that such a multi-group three-tuple cross-eye jamming structure performs better than the multi-element cross-eye jamming structure previously proposed, and the analysis of the centroid shows that the centroid of the structure proposed in this paper is more widely distributed in space.

关键词： electronic warfare(EW) angular deception jamming cross-eye jamming three-tuple antenna array near field

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2013年龙岩市碘盐监测结果分析

中国卫生标准管理 2014年第23期5卷 66-68页

作者：周志鹏陈建森池雪萍陈庆平陈建安龙岩市疾病预防控制中心福建龙岩364000

为了解2012年新的食品安全国家标准《食用盐碘含量》(GB 26878-2011)实施后,龙岩市居民食用碘盐的质量情况,2013年在龙岩市开展了碘盐抽样监测工作。结论 :龙岩市碘盐供应合格,居民碘盐食用合理。

关键词：碘盐类结果分析

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信息内外网边界安全监测系统的设计与实施

电力与能源 2019年第1期40卷 59-62页

作者：叶水勇吴斌陈清萍蔡翔方圆陈明刘琦国网黄山供电公司安徽黄山245000 国网安徽省电力有限公司合肥230022 国网安徽信通公司合肥230061

随着信息化建设的全面推广,信息安全领域面临来自于企业外部的层出不穷的入侵和攻击,也有来自内部的违规和泄漏。针对存在的诸多信息安全问题,通过对信息内外网边界安全监测系统的技术方案及关键技术进行了全面阐述,提出通过采集信息网... 详细信息

随着信息化建设的全面推广,信息安全领域面临来自于企业外部的层出不穷的入侵和攻击,也有来自内部的违规和泄漏。针对存在的诸多信息安全问题,通过对信息内外网边界安全监测系统的技术方案及关键技术进行了全面阐述,提出通过采集信息网路各个边界、各种系统、各类设备的安全事件与安全日志,基于大数据分析技术进行交叉分析与关联分析,不仅实现了对各边界安全态势的集中评估和告警,还能够实现全网安全态势的综合评估以及安全事件的分析,从而提高了信息安全的管控水平。

关键词：安全监测网络隔离数据采集数据分析架构体系

Testing and Modeling of the Dynamic Response Characteristics of Pulsating Heat Pipes during the Start-up Process

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Journal of Thermal Science 2019年第1期28卷 72-81页

作者： XU Rongji chen Hao WU qingping XU Shuhui WANG Ruixiang Beijing Engineering Research Center of Sustainable Energy and Buildings Beijing University of Civil Engineering and Architecture School of Energy and Power Engineering Xi'an Jiaotong University

Pulsating heat pipes(PHPs) are two-phase heat transfer heat pipes with high heat transfer capability and simple structure. Heating power is an important factor that affects the start-up response characteristics of PHPs. The operational characteristics during the start-up and stable operating stages were studied through experiments, and the corresponding dynamic response model under a specified heating power was established based on experimental data and flow pattern in the tube. The starting time, starting temperature, and dynamic response characteristic parameters at a certain heating power were calculated by the dynamic response model. The response characteristics of working fluid during the stable operation of PHPs were deduced based on the dynamic response curve of PHPs during the non-operational and stable operation stages. The response characteristics of PHPs for the step effect(given heating power) were quantitatively described by amplification factor K and time constant τ, thereby presenting the basis for the study on heat and mass transfer mechanisms of PHPs from non-operational to steady operation stage. Results showed that the minimum thermal resistance and the minimum time constant of the PHP are approximately 0.28 °C/W and 75, respectively, obtained at a heating power of 160 W. Moreover, these results indicated that the dynamic response of PHPs demonstrates a favourable performance and rapidly reaches another stable working state when their heat transfer performance is stable. However, the dynamic response time constant of pure fluids decreases when the quantity of the liquid working fluid in the PHP decreases with the increase in heating power.

关键词： pulsating heat pipe heating power dynamic response characteristic time constant amplification factor

Effects of grain size on phase transition behavior of nanocrystalline shape memory alloys

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Science China(Technological Sciences) 2014年第4期57卷 671-679页

作者： SUN qingping ASLAN Ahadi LI MingPeng chen MingXiang Department of Engineering Mechanics Wuhan University Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology

We report recent advances in the experimental and theoretical study of grain size(GS)effects on the thermal and mechanical properties of nanostructured NiTi polycrystalline shape memory alloy(SMA).It is shown that when GS<60 nm,the superelastic stress-strain hysteresis loop area(H)of the polycrystal decreases rapidly with GS and tends to vanish as GS approaches 10 *** the same time,the temperature dependence of the transition stress also decreases with GS and eventually approaches zero,leading to a wide superelastic temperature window and breakdown of the Clausius-Claperyon *** dependence of the stress-strain responses is significantly reduced and the cyclic stability of the material is improved by the *** is proposed that the emergence of such significant changes in the behavior of the material with GS reduction originate from the large increase in the area-to-volume ratios of the nanometer-thick interfaces(grain boundary and Austenite-Martensite(A-M)interface)in the *** particular,with GS reduction,interfacial energy terms will gradually become dominant over the bulk energy of the crystallite,eventually bring fundamental changes in the phase transition responses of the *** strategy leading to the establishment of quantitative relationships among GS,grain boundary,A-M interfaces and the macroscopic responses of the material are outlined.

关键词： grain size effects phase transition behavior grain boundary and austenite-martensite (A-M) interface nanocrystalline NiTi shape memory alloys