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Journal of Materials Science & Technology 2024年第5期172卷 1-14页

作者： Yaofeng Luo Yan Wang Li Wang Bin liu yong liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl ***,the underlying DRX mechanism remains poorly *** this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction *** addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first *** re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic *** origin of the twin intersection and TDRX for the composite was *** stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin *** high stored strain energy at the regions of twins and twin intersections provided the driving force for *** accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)*** present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.

关键词： TiAl matrix composite Al_(2)O_(3)fiber Twin intersection Dynamic recrystallization

Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8Mo stainless steel

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Journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang liu Chang-jun Wang Chang liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23C precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property

液相隔膜辉光放电发射光谱法检测水中钾和钠离子

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光谱学与光谱分析 2013年第9期33卷 2570-2573页

作者：刘永军王蕾大连海事大学环境科学与工程学院辽宁大连116026 厦门理工学院水资源环境研究所福建厦门361024

研究了液相隔膜辉光放电发射光谱法对水中钾离子和钠离子的检测性能,考察了外加电压和有机添加剂甲醇对检测灵敏度和检出限的影响。结果表明提高外加电压和添加甲醇能提高检测灵敏度和降低检出限。在电压850V,添加0.6%～0.8%甲醇时钾和... 详细信息

研究了液相隔膜辉光放电发射光谱法对水中钾离子和钠离子的检测性能,考察了外加电压和有机添加剂甲醇对检测灵敏度和检出限的影响。结果表明提高外加电压和添加甲醇能提高检测灵敏度和降低检出限。在电压850V,添加0.6%～0.8%甲醇时钾和钠的检出限分别为0.007和0.001mg·L-1。液相隔膜辉光放电发射光谱法检测水中金属离子具有背景光谱干扰小和灵敏度高的特点。

关键词：液相隔膜辉光放电发射光谱检测

Anomalous thermal expansion and enhanced magnetocaloric effect in<001>-textured Mn_(x)Fe_(5-x)Si_(3) alloys

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Rare Metals 2024年第5期43卷 2263-2274页

作者： yong Gong Xue-Fei Miao Tapas Samanta Chris Taake jun liu Feng-Jiao Qian Yan-Yan Shao Yu-Jing Zhang Qing-yong Ren Luana Caron Feng Xu MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing210094China Department of Physics Bielefeld University33501BielefeldGermany College of Physics Nanjing University of Aeronautics and AstronauticsNanjing210016China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center Dongguan523803China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan523803China Department of Physics Bielefeld University33501BielefeldGermany Helmholtz-Zentrum Berlin für Materialien und Energie12489BerlinGermany

The development of zero and negative therma expansion(i.e.,ZTE and NTE)materials is of crucial importance to the control of undesirable thermal expansion for high-precision *** the present work,ZTE and NTE were obtained in directionally-solidified Mn_(x)Fe_(5-x)Si_(3)alloys with a strongtexture,in striking contrast to positive thermal expansion in their isotropic counterparts Magnetometry and in-situ X-ray diffraction(XRD)measurements were performed to uncover the origin of the anomalous thermal *** measurements indicate a strong easy-plane magnetocrystalline anisotropy in the textured samples,where the magnetic moments are aligned within the ab plane of the hexagonal structure Temperature-dependent XRD on the x=1 sample reveals a ZTE character in the ab plane that is coupled to a ferromagnetic *** a result,the macroscopic ZTE(~0.22×10^(-6)K^(-1))in the x=1 sample can be attributed to the microscopic magneto volume effect within the ab plane,which is realized by the introduction of the-textured ***,the competition between antiferromagnetic and ferromagnetic exchange coupling leads to NTE in textured x=1.5 and 2 ***,textured x=1 sample displays enhanced magnetocaloric properties as compared to the conventional counterparts with randomly-oriented *** this work demonstrates a new strategy toward the exploration of anomalous thermal expansion properties as well as the enhancement of magnetocaloric properties for materials with a strong magnetocrystalline anisotropy.

关键词： MnFeySis Magnetocaloric effect Magnetic phase transition Negative thermal expansion

Highly efficient and wearable thermoelectric composites based on carbon nanotube film/polyaniline

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Journal of Materiomics 2024年第1期10卷 173-178页

作者： Jing Huang Xiaohua liu yong Du School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai201418China

Polyaniline(PANI)was prepared by in-situ polymerization and compounded on the two-dimensional network structural multi-walled carbon nanotube film(CNTF).Compared with the CNT/PANI composites fabricated by using CNT powders or dispersions,the compact and continuous network structure of CNTF/PANI is beneficial to both the thermoelectric and mechanical properties of the *** resultant CNTF/PANI composites with PANI polymerization time of 5 h obtain an electrical conductivity of 1338.4 S/cm and Seebeck coefficient of 63.3μV/K at 360 K,which are 168.7%and 5.7%higher than those of the CNTF(498.1 S/cm and 59.9μV/K at 360 K).Consequently,a maximum power factor of 536.8μW·m^(−1)·K^(−2) at 360 K is acquired,which is about 2 times higher than that of CNTF(181.7μW·m^(−1)·K^(−2) at 360 K).The electrical conductivity of the composites could maintain 93.3%after being bent for 500 times,indicating the excellent *** tensile strength,Young's Modulus and toughness of CNTF/PANI composites(232.3 MPa,3.6 GPa and 20.1 MJ/m^(3),respectively)are 3.5,2.6 and 2.1 times of those of the *** flexible,free-standing,lightweight and high-strength CNTF/PANI composites reveal the excellent thermoelectric performance,which are promising in the applications in wearable thermoelectric devices.

关键词： Carbon nanotube film Polyaniline Thermoelectric performance Mechanical properties

Cross-scale mechanical softening of Marcellus shale induced by CO_(2)-water-rock interactions using nanoindentation and accurate grain-based modeling

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Underground Space 2024年第6期19卷 26-46页

作者： Yiwei liu Quansheng liu Zhijun Wu Shimin liu yong Kang Xuhai Tang School of Civil Engineering Wuhan UniversityWuhan 430072China Department of Energy and Mineral Engineering G3 Center and EMS Energy InstituteThe Pennsylvania State UniversityUniversity ParkPA 16802USA School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

Mechanical softening behaviors of shale in CO_(2)-water–rock interaction are critical for shale gas exploitation and CO_(2)*** work investigated the cross-scale mechanical softening of shale triggered by CO_(2)-water–rock ***,the mechanical softening of shale following 30 d of exposure to CO_(2)and water was assessed at the rock-forming mineral scale using *** mechanical alterations of rock-forming minerals,including quartz,muscovite,chlorite,and kaolinite,were analyzed and ***,an accurate grain-based modeling(AGBM)was proposed to upscale the nanoindentation *** models were generated based on the real microstructure of shale derived from TESCAN integrated minerals analyzer(TIMA)digital *** parameters of shale minerals determined by nanoindentation served as input material properties for ***,numerical simulations of uniaxial compression tests were conducted to investigate the impact of mineral softening on the macroscopic Young’s modulus and uniaxial compressive strength(UCS)of *** results present direct evidence of shale mineral softening during CO_(2)-water–rock interaction and explore its influence on the upscale mechanical properties of *** paper offers a microscopic perspective for comprehending CO_(2)-water-shale interactions and contributes to the development of a cross-scale mechanical model for shale.

关键词： Shale Cross-scale modeling Nanoindentation CO_(2)-water-rock interaction Mechanical softening

A progressive framework for rotary motion deblurring

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Defence Technology（防务技术） 2024年第2期32卷 159-172页

作者： Jinhui Qin yong Ma jun Huang Fan Fan You Du School of Electronic Information Wuhan UniversityWuhan430072China

The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating *** rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur *** solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement *** the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details *** a novel deconvolution model is proposed based on BE *** the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling *** establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur *** results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur *** code and dataset are available at https://***/JinhuiQin/RotaryDeblurring.

关键词： Rotary motion deblurring Progressive framework Blur extents factor TDM-CNN

Machine learning-based predictions of current and future susceptibility to retrogressive thaw slumps across the Northern Hemisphere

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Advances in Climate Change Research 2024年第2期15卷 253-264页

作者： Jing LUO Guo-An YIN Fu-jun NIU Tian-Chun DONG Ze-yong GAO Ming-Hao liu Fan YU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. LtdXining 810000China University of Chinese Academy of Sciences Beijing 100049China

Retrogressive thaw slumps(RTSs)caused by the thawing of ground ice on permafrost slopes have dramatically increased and become a common permafrost hazard across the Northern Hemisphere during previous ***,a gap remains in our comprehensive understanding of the spatial controlling factors,including the climate and terrain,that are conducive to these RTSs at a global *** machine learning methodologies,we mapped the current and future RTSs susceptibility distributions by incorporating a range of environmental factors and RTSs *** identified freezing-degree days and maximum summer rainfall as the primary environmental factors affecting RTSs *** final ensemble susceptibility map suggests that regions with high to very high susceptibility could constitute(11.6±0.78)%of the Northern Hemisphere's permafrost *** juxtaposed with the current(2000-2020)RTSs susceptibility map,the total area with high to very high susceptibility could witness an increase ranging from(31.7±0.65)%(SSP585)to(51.9±0.73)%(SSP126)by the *** insights gleaned from this study not only offer valuable implications for engineering applications across the Northern Hemisphere,but also provide a long-term insight into the potential change of RTSs in permafrost regions in response to climate change.

关键词： Retrogressive thaw slump Machine learning Susceptibility map Permafrost Northern Hemisphere

Highly Thermally Conductive Polydimethylsiloxane Composites with Controllable 3D GO@f-CNTs Networks via Self-sacrificing Template Method

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Chinese Journal of Polymer Science 2024年第7期42卷 897-906,I0005页

作者： Shuang-Shuang Wang Dian-Ying Feng Zhi-Ming Zhang Xia liu Kun-Peng Ruan yong-Qiang Guo jun-Wei Gu Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an710072China Shandong Institute of Nonmetallic Materials Jinan250031China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an710072China

Constructing controllable thermal conduction networks is the key to efficiently improve thermal conductivities of polymer *** this work,graphite oxide(GO)and functionalized carbon nanotubes(f-CNTs)are combined to prepare“Line-Plane”-like hetero-structured thermally conductive GO@f-CNTs fillers,which are then performed to construct controllable 3D GO@f-CNTs thermal conduction networks via selfsacrificing template method based on oxalic ***,thermally conductive GO@f-CNTs/polydimethylsiloxane(PDMS)composites are fabricated via casting *** the size of oxalic acid is 0.24 mm and the volume fraction of GO@f-CNTs is 60 vol%,GO@f-CNTs/PDMS composites present the optimal thermal conductivity coefficient(λ,4.00 W·m^(-1)·K^(-1)),about 20 times that of theλof neat PDMS(0.20 W·m^(-1)·K^(-1)),also much higher than theλ(2.44 W·m^(-1)·K^(-1))of GO/f-CNTs/PDMS composites with the same amount of randomly dispersed ***,the obtained GO@f-CNTs/PDMS composites have excellent thermal stability,whoseλdeviation is only about 3%after 500 thermal cycles(20-200℃).

关键词： Polydimethylsiloxane Hetero-structured thermally conductive fillers Self-sacrificing template Thermal conduction networks

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钐试剂在有机合成中应用的若干新进展

化学学报 2005年第5期63卷 341-351页

作者：刘永军张永敏浙江大学化学系杭州310028

综述了本课题组最近几年关于钐试剂在有机合成中应用的研究进展.主要包括以下几部分内容(1)二碘化钐促进的有机反应研究;(2)金属钐直接应用于有机合成的研究;(3)其它钐试剂(三碘化钐,烯丙基溴化钐)促进的有机反应研究.

关键词：钐试剂有机合成工艺二碘化钐金属钐烯丙基溴化钐偶联反应