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Shape Memory Effect,Thermal Expansion and Damping Property of Friction Stir Processed NiTip/Al Composite

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Journal of materials Science & Technology 2016年第2期32卷 162-166页

作者： D.r.Ni J.J.Wang Z.Y.ma Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang I10016China College of material Science and Engineering ShenyangAerospace University Shenyang 110136China

NiTi particles reinforced aluminum （NiTip/Al） composite was prepared via friction stir processing, elimi- nating interfacial reaction and/or elemental diffusion. The NiTip in the composite maintained the intrinsic characteristic of a reversible thermoelastic phase transformation even after heat-treatment. The shape memory characteristic of the NiTip decreased the coefficient of thermal expansion of the Al matrix, and an apparent two-way shape memory effect was observed in the composite. The composite owned a good combination of adjustable damping and thermal physical properties.

关键词： Metal matrix composite Shape memory alloy Interface Differential scanning calorimetry (DSC)Damping

水文模型在生态系统水文服务评估中的应用综述

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水生态学杂志 2025年第1期46卷 166-176页

作者：徐子萱郑华马金锋中国科学院生态环境研究中心城市与区域国家重点实验室北京100085 中国科学院大学北京101408

阐述了生态系统水文服务的内涵和表征要求,并通过分析水文模型的输出指标,梳理其与生态系统水文服务之间的映射关系,明确水文模型可以支撑的生态系统服务类型;系统总结多种水文模型在评估生态系统水文服务(供给服务、调节服务、文化服... 详细信息

阐述了生态系统水文服务的内涵和表征要求,并通过分析水文模型的输出指标,梳理其与生态系统水文服务之间的映射关系,明确水文模型可以支撑的生态系统服务类型;系统总结多种水文模型在评估生态系统水文服务(供给服务、调节服务、文化服务和支持服务)中的应用进展,指出不同水文模型在原理、输出指标、时空尺度及可评估的生态系统服务类型上的差异;强调了水文模型在预测生态系统水文服务变化、探究服务形成机理及流域管理服务等方面的应用;最后从变革模型的计算模式、变革参数率定模式、整合受益者模块以及加强模型间耦合4个角度指出了从生态系统服务视角促进水文模型深入应用的发展方向。

关键词：水文模型水文服务生态系统评估指标

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Achieving strength-ductility synergy in novel paramagnetic Fe-based medium-entropy alloys through deep cryogenic deformation

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rare Metals 2024年第9期43卷 4493-4507页

作者： Hu-Wen ma Yan-Chun Zhao Li Feng Tian-Zeng Liu Zhi-Qi Yu Bo Jin Wang-Chun Duan Peter k.Liaw Dong ma State key Laboratory of Advanced Processing and recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou 730050China Wenzhou Pump and Valve Engineering research Institute Lanzhou University of TechnologyWenzhou 325105China Iron and Steel research Institute Jiuquan Iron and Steel CorporationJiayuguan 735100China Lanzhou resources and Environment Voc-Tech University Lanzhou 730123China Department of materials Science and Engineering The University of TennesseeKnoxvilleTN 37996-2200USA Neutron Science Center Songshan Lake Materials LaboratoryDongguan 523808China

Cryogenic pre-deformation treatment has been widely used to effectively improve the comprehensive mechanical properties of steels and novel ***,the dislocation evolution and phase transformation induced by different degrees of deep cryogenic deformation are not yet fully *** this study,the effects of multiple cryogenic pre-treatments on the mechanical properties and deformation mechanisms of a paramagnetic Fe_(63.3)Mn_(14-)Si_(9.1)Cr_(9.8)C_(3.8)medium-entropy alloy(MEA)were investigated,leading to the discovery of a pretreated MEA that exhibits exceptional mechanical properties,including a fracture strength of 3.0 GPa,plastic strain of 26.1%and work-hardening index of *** addition,X-ray diffraction(XrD)and transmission electron microscopy(TEM)analyses revealed that multiple cryogenic pre-deformation treatments significantly increased the dislocation density of the MEA(from 9×10^(15)to 4×10^(16)m^(-2)after three pretreatments),along with a transition in the dislocation type from predominantly edge dislocations to mixed dislocations(including screw-and edge-type dislocations).Notably,this pretreated MEA retained its paramagnetic properties(μ_(r)r *** calculations showed that cryogenic pretreatment can significantly reduce the stacking fault energy of the MEA by a factor of approximately four(i.e.,from 9.7 to2.6 m J·m^(-2)),thereby activating the synergistic effects of transformation-induced plasticity,twinning-induced plasticity and dislocation strengthening *** synergistic effects lead to simultaneous strength and ductility enhancement of the MEA.

关键词： Deep cryogenic transformation Iron-based medium-entropy alloys Dislocation evolution Phase transformation Stacking fault energy

Cavefish as biological models in the laboratory and in the wild

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Zoological research 2023年第4期44卷 834-836页

作者： William r.Jeffery Li ma Ya-hui Zhao Department of Biology University of MarylandCollege ParkMD20742 USA Cave Fish Development and Evolution research Group Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan650223China Institute of Zoology Chinese Academy of SciencesBeijing100101China

Cavefish have advanced to the forefront as excellent models for laboratory studies in developmental and evolutionary *** iconic Mexican characid,Astyanax mexicanus,which consists of a surface-dwelling morph and about 30 interfertile cave-dwelling morphs,has become a major contributor to behavior,sensory biology,trait evolution,and biomedicine(Jeffery,2020).There are about 200 scientifically-described cavefish species distributed in karst areas on most continents(Proudlove,2015).Similar to ***,a small subset of other cavefish taxa coupled with related surface-dwelling species are now serving as additional laboratory models to address a variety of important biological problems.A prime example is the cyprinid genus Sinocycloceilus,which contains 75 closely related surface and cave species endemic to the karst massifs of southwestern China(Jiang et al.,2019,2023;ma et al.,2019).Comparative studies of Chinese and Mexican cavefish can be used to address a host of questions concerning the convergence and divergence of cave related *** the future,other Chinese cavefish species,such as the cave loach,as well as the more recently discovered European cavefishes,are likely to join the current group of excellent laboratory *** special issue of Zoological research presents the results of current research on these diverse cavefish *** addition to recent research using cavefish models in laboratory studies,this issue also covers new research on cavefish in the wild.

关键词： species fish traits

鄱阳湖全天候水位-面积逐日数据集(2014-2023年)

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湖泊科学 2025年第2期37卷 689-704页

作者：李昕悦谢涛马荣华南京信息工程大学遥感与测绘工程学院南京210044 中国科学院南京地理与湖泊研究所湖泊与流域水安全重点实验室南京211135 中国科学院大学南京学院南京211135

在气候变化与人类活动的影响下,鄱阳湖洪涝灾害和干旱频发,严重影响鄱阳湖流域的生态环境。本研究旨在通过雷达遥感技术,准确监测鄱阳湖水域面积全天候的时空动态变化,为鄱阳湖水资源评估和旱涝灾害预警提供科学依据。基于2014-2023年Se... 详细信息

在气候变化与人类活动的影响下,鄱阳湖洪涝灾害和干旱频发,严重影响鄱阳湖流域的生态环境。本研究旨在通过雷达遥感技术,准确监测鄱阳湖水域面积全天候的时空动态变化,为鄱阳湖水资源评估和旱涝灾害预警提供科学依据。基于2014-2023年Sentinel-1影像,分别利用单波段阈值法、双极化水体指数以及谱间关系法,结合最大类间方差法自适应确定阈值提取水体,通过精度评价,选定最优提取方法,应用于全天候鄱阳湖水域面积提取。结合星子站、湖口站水位数据,揭示水位变化与湖泊水域面积关系,得到鄱阳湖全天候水位-面积逐日数据集,该数据集包括2014-2023年共424期鄱阳湖水域栅格数据、水域面积汇总数据以及星子站、湖口站水位数据,数据集存储为.tif、.xlsx格式。同时,利用湖泊水域面积时间序列曲线的扰动事件识别方法,识别2020年和2022年面积突变的主要因素。结果表明:谱间关系法结合最大类间方差法的阈值分割法的提取精度最优(总体精度>95%);2016-2023年间,鄱阳湖的水域面积呈现显著的年内变化,主要集中在河道以及湖中部。水位与面积变化总体趋于一致,水位≥14 m时,水位变化与湖泊水域面积变化呈现显著正相关。从湖泊时间序列扰动结果分类可以看出,2020年湖泊水域面积扩张的主要原因是自然因素,2022年湖泊水域面积骤减的主要原因是人为因素。

关键词：水域面积鄱阳湖 Sentinel-1 Google Earth Engine 时序变化

robust stability analysis for a cruise missile

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Journal of Systems Engineering and Electronics 2008年第4期19卷 785-790页

作者： Shi Yingjing ma Guangfu ma Hongzhong School of Astronautics Harbin Inst. of Technology Harbin 150001 P. R. China Third research Academy of China Aerospace Science and Industry Corporation Beijing 100074 P. R. China

A global controller design methodology for a flight stage of the cruise missile is proposed. This methodology is based on the method of least squares, To prove robust stability in the full airspace with parameter disturbances, the concepts of convex polytopic models and quadratic stability are introduced, The effect of aerodynamic parameters on system performance is analyzed. The designed controller is applied to track the overloading signal of the cruise segment of the cruise missile, avoiding system disturbance owing to controller switching, Simulation results demonstrate the validity of the proposed method.

关键词： aircraft control robust control least square quadratic stabilization

Local spatial properties based image interpolation scheme using SVMs

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Journal of Systems Engineering and Electronics 2008年第3期19卷 618-623页

作者： ma Liyong Shen Yi ma Jiachen School of Information Science and Engineering Harbin Inst. of Technology Weihai 264209 P. R. China

Image interpolation plays an important role in image process applications. A novel support vector machines （SVMs） based interpolation scheme is proposed with increasing the local spatial properties in the source image as SVMs input patterns. After the proper neighbor pixels region is selected, trained support vectors are obtained by training SVMs with local spatial properties that include the average of the neighbor pixels gray values and the gray value variations between neighbor pixels in the selected region. The support vector regression machines are employed to estimate the gray values of unknown pixels with the neighbor pixels and local spatial properties information. Some interpolation experiments show that the proposed scheme is superior to the linear, cubic, neural network and other SVMs based interpolation approaches.

关键词： image processing interpolation support vector machines local spatial properties support vectorregression.

kinetics of Al Evaporation from Liquid U-Al Alloys in Vacuum Induction Melting

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Journal of materials Science & Technology 2015年第4期31卷 423-426页

作者： Y.J.Duan B.Chen Y.C.ma k.Liu materials for Special Environment Division Institute of Metal ResearchChinese Academy of Sciences

A research on kinetics of Al evaporation from liquid U—Al alloys was made in a vacuum induction melting（VIM） furnace at 1673—1843 *** evaporation rate of Al was found to be first order with respect to Al content in the *** overall mass transfer coefficient of Al was determined and it was found that the evaporation rate of Al increased with increasing *** apparent activation energy of Al evaporation at 1673-1843 k was 171.5 kJ *** value of mass transfer coefficient of Al in the liquid phase was estimated to be 3.77 × 10-6,7.41×10-6,and 9.40 × 10-6m s-1at 1673,1753,and 1843 k,***,rate determining steps were discussed and it was concluded that the evaporation rate of Al is mainly controlled by liquid phase mass transfer.

关键词： Al evaporation kinetics Liquid U-Al alloys mass tr

Experimental demonstration of D-band signals wireless transmission over 30 km

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Science China(Technological Sciences) 2025年第2期68卷 318-320页

作者： Yi WEI Xiongwei YANG Jianjun YU Xianming ZHAO Mingxu WANG Jingwen TAN Weiping LI Feng ZHAO Chengzhen BIAN Hansong ma Qinyi ZHANG Qiutong ZHANG Bing Zhang Wen ZHOU kaihui WANG Sicong XU Jianguo YU State key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves(MoE)and School of Information Science and TechnologyFudan UniversityShanghai 200433China Harbin Institute of Technology Harbin 150001China School of Automation Xi’an University of Posts and TelecommunicationsXi’an 710121China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Due to the rise of innovative technologies like artificial intelligence(AI),the Internet of Things(IoT),and telemedicine,the demand for internet traffic is rapidly *** order to achieve ultra-high-speed wireless communication,many researchers are directing their efforts towards the *** D-band,spanning the frequency band 110-170 GHz,has abundant spectrum resources and license-free characteristics[1,2].

关键词： IoT wireless band

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