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journal of Materials Science & Technology 2012年第11期28卷 1046-1052页

作者： R.L.Lju y.j.qiao M.F.yan y.D.Fu College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Low temperature plasma nitrocarburizing of 17-4PH martensitic stainless steel was conducted at 430 ℃ with and without rare earth （RE） addition. The microstructure, kinetics, microhardness, wear behavior as well as corrosion resistance of the modified layer were studied by optical microscopy, X-ray diffraction, Vickers microhardness tester, pin-on-disc tribometer and potentiodynamic polarization tests. The results show that the thickness of plasma RE nitrocarburized layer is much thicker than that formed by nitrocarburizing without RE addition. The incorporation of RE does not change the kind of the phases and the nitrocarburized layer consists mainly of nitrogen and carbon expanded martensite （aN）, γ-Fe4N and a-Fe with a trace of CrN phases. The surface microhardness of plasma nitrocarburized layer can be increased by 100 HV after RE addition. Wear resistance of the specimen can be apparently improved by low temperature plasma nitrocarburizing with and without RE addition and without sacrificing its corrosion resistance. Wear reduction effect of low temperature plasma nitrocarburizing with RE addition is better than that of the conventional one.

关键词： Stainless steel Low temperature Plasma nitrocarburizing Rare earth (RE) Wear and friction

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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journal of Energy Chemistry 2025年第1期100卷 710-720页

作者： Wenxuan Chen Xiu-Qing qiao Guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian Wu Tao Wu Dong-Sheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory College of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo2C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-CdS （c-CdS） and hexagonal-CdS （h-CdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge ***,the photothermal effect of Mo2C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Cadmium sulfide

联邦权与州权的平衡:约翰·马歇尔对州治安权的阐释及其运用

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史学集刊 2025年第1期 121-132页

作者：郭巧华福建师范大学社会历史学院福建福州350007

约翰·马歇尔是美国第四任首席大法官。在早期美国州权主义强势、政党纷争不已的背景下,他带领最高法院的同仁,通过对宪法文本的阐释,极大地加强了联邦权,削弱了州权,引发了州权主义者的猛烈批评。不过,马歇尔并非积极的国家主义者,他... 详细信息

约翰·马歇尔是美国第四任首席大法官。在早期美国州权主义强势、政党纷争不已的背景下,他带领最高法院的同仁,通过对宪法文本的阐释,极大地加强了联邦权,削弱了州权,引发了州权主义者的猛烈批评。不过,马歇尔并非积极的国家主义者,他在相关案件中对州治安权的阐释及其案例判决表明,马歇尔及这一时期最高法院的大法官们都清楚地意识到,各州在其治安权的管辖范围内,依然行使着州内治理等大量政府功能,应该予以肯定和支持。实际上,联邦保有宪法列举的必要且至上的权力,而各州保留剩余的权力,联邦权与州权平衡互动,这不仅是制宪精英们的意图,也是现实的需求。

关键词：美国最高法院约翰·马歇尔州治安权联邦权

Main α relaxation and slow β relaxation processes in a La30Ce30Al15Co25 metallic glass

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journal of Materials Science & Technology 2019年第6期35卷 982-986页

作者： j.C. qiao y.H. Chen R. Casalini j.M. Pelletier y. yao School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710072 China Chemistry Division Naval Research Laboratory Code 6120 Washington DC 20375-5342 United States Universite de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurbanne cedex France

Dynamic relaxation processes are fundamental to understand the mechanical and physical properties of metallic glasses. In the current work, mechanical relaxations in a La30Ce30Al15Co25 bulk metallic glass were probed by dynamic mechanical analysis. In contrast to many metallic glasses, La30Ce30Al15Co25 metallic glass shows a pronounced slow β relaxation peak. Physical aging below the glass transition temperature Tgleads to an increase of the apparent activation energy and a decrease of the slow β relaxation magnitude. The correlation between the slow β relaxation and the main α relaxation is discussed.

关键词： Mechanical relaxation Dynamic mechanical relaxation α Relaxation β relaxation Physical aging

Training β relaxation to rejuvenate metallic glasses

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journal of Materials Science & Technology 2023年第27期158卷 53-62页

作者： L.T.Zhang yun-jiang Wang y.yang j.C.qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Department of Mechanical Engineering College of EngineeringCity University of Hong KongTat Chee AvenueKowloon TongKowloonHong Kong SARChina Department of Materials Science and Engineering College of EngineeringCity University of Hong KongTat Chee AvenueKowloon TongKowloonHong Kong SARChina Innovation Center NPU-ChongqingChongqing 401135China

In the current work,we demonstrated that the rejuvenation of metallic glasses can be achieved through training theβrelaxation *** the increase in the training frequency,a transition from structural relaxation to rejuvenation can be *** rejuvenation treatment is unexpected due to it occurs at a relatively small cyclic strain of 0.2%.Rejuvenation is beneficial to increase the relaxation enthalpy and promotes the decoupling of theβrelaxation process andαrelaxation process.A cluster ofβrelaxation time curves are formulated to describe any energetic state between ultrastable and ultimately rejuvenated metallic *** addition,rejuvenation expands the distribution ofβrelaxation process,anelastic and viscoplastic components during the deformation process.

关键词： Metallic glass βrelaxation Rejuvenation Structural heterogeneity

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党内法规视域下纪律建设的历史轨迹

学习论坛 2025年第1期 44-55页

作者：乔贵平王泽人天津师范大学政治与行政学院天津300387

严明的纪律是中国共产党在长期奋斗实践中铸造的组织品格。从党的建设历程来看,纪律建设从建党伊始就是明确的组织意识,也是党加强自身治理的重要内容。在百余年发展过程中,中国共产党从完善纪律法规、加强纪律教育、优化纪检机构、严... 详细信息

严明的纪律是中国共产党在长期奋斗实践中铸造的组织品格。从党的建设历程来看,纪律建设从建党伊始就是明确的组织意识,也是党加强自身治理的重要内容。在百余年发展过程中,中国共产党从完善纪律法规、加强纪律教育、优化纪检机构、严格纪律执行等方面不断延展与深化纪律建设,在遵循党章、依规治党、纪律治党中推进党的纪律建设。在新民主主义革命时期,中国共产党将纪律严明作为组织严密的坚强保障,奠定了革命胜利的基础;在社会主义革命和建设时期,为适应执政党的角色和国家治理的需要,党的纪律建设内容内核愈发清晰,“纪律与党的中心任务”“纪律与团结统一”的关系进一步凸显,彰显了纪律在维护党的团结统一和推进中心任务中的重要作用;在改革开放和社会主义现代化建设新时期,从严治党、严肃党纪成为党内治理的基本要求,党在反腐倡廉制度体系中突出纪律,纪律建设逐步制度化;中国特色社会主义进入新时代,党的纪律不仅成为维护党内秩序、规范党员行为的治本之策,也在全社会形成强大的纪律震慑力,推动党内法规与国家法律的有机衔接,确保党的纪律规矩严明,推动全面从严治党向纵深发展。

关键词：纪律建设党内法规从严治党纪律治党

Mechanical Relaxation of a Ti36.2Zr30.3Cu8.3Fe4Be21.2 Bulk Metallic Glass: Experiments and Theoretical Analysis

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Acta Metallurgica Sinica(English Letters) 2019年第6期32卷 726-732页

作者： j.C.qiao y.H.Chen G.j.Lyu K.K.Song j.M.Pelletier y.yao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China School of Mechanical Electrical and Information EngineeringShandong University(Weihai)Weihai 264209China MATEIS UMR CNRS5510Bat.B.PascalINSA-LyonUniversite de Lyon69621 Villeurbanne CedexFrance

The dynamic mechanical relaxation behavior of Ti36.2Zr30.3Cu8.3Fe4Be21.2 bulk metallic glass with good glass-forming ability was investigated by mechanical *** mechanical relaxation behavior was analyzed in the framework of quasi-point defects *** experimental results demonstrate that the atomic mobility of the metallic glass is closely associated with the correlation factorχ.The physical aging below the glass transition temperature T g shows a non-Debye relaxation behavior,which could be well described by stretched Kohlrausch exponential *** Kohlrausch exponentβaging reflects the dynamic heterogeneities of the metallic *** concentration of"defects"and atomic mobility decrease caused by the in situ successive heating during the mechanical spectroscopy experiments.

关键词： Metallic glasses Mechanical relaxation Physical aging Quasi-point defects

Effect of rolling ratios on the microstructural evolution and corrosion performance of an as-rolled Mg-8wt.%Li alloy

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journal of Magnesium and Alloys 2021年第2期9卷 560-568页

作者： B.j.Wang D.K.Xu X.Cai y.X.qiao L.y.Sheng School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiangChina Peking University Shenzhen InstituteShenzhen Key Lab Human Tissue Regenerate&RepairShenzhen 518057China

In this work,the influence of rolling ratios on microstructural changes and corrosion behavior of an as-rolled Mg-8 wt.%Li alloy in0.1 mol/L Na Cl solution has been *** revealed that with the rolling ratio being increased from 3 to 10,theα-Mg phases were elongated and fragmented,whilst the area fraction of exposedβ-Li phases ***,the corrosion performance of the alloy decreased with the increased rolling *** all the samples,their corrosion processes were quite similar and can have two *** the initial stage with the samples being immersed for less than 6 h,the corrosion mainly occurred inβ-Li *** the samples were immersed for longer than 6 h,the corrosion attack transferred toα-Mg phases and the hydrogen evolution rate was accelerated.

关键词： Mg-li alloys Wrought Microstructure Corrosion performance

Molecular Dynamics Simulation of Porous Layer-enhanced Dislocation Emission and Crack Propagation in Iron Crystal

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journal of Materials Science & Technology 2011年第11期27卷 1025-1028页

作者： D. Li F.y. Meng X.Q. Ma L.j. qiao W.y. Chu Department of Physics University of Science and Technology Beijing Beijing 100083 China Corrosion and Protection Center Key Lab of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The internal stress induced by a porous layer or passive layer can assist the applied stress to promote dislocation emission and crack propagation, e.9. when the pipeline steel is buried in the soil containing water, resulting in stress corrosion cracking （SCC）. Molecular dynamics （MD） simulation is performed to study the process of dislocation emission and crack propagation in a slab of Fe crystal with and without a porous layer on the surface of the crack. The results show that when there is a porous layer on the surface of the crack, the tensile stress induced by the porous layer can superimpose on the external applied stress and then assist the applied stress to initiate crack tip dislocation emission under lowered stress intensity KI, or stress. To respond to the corrosion accelerated dislocation emission and motion, the crack begins to propagate under lowered stress intensity KI, resulting in SCC.

关键词： Molecular dynamics simulation Dislocation emission Crack propagation Porouslayer Stress intensity

Dynamic Mechanical Relaxation in Bulk Metallic Glasses:A Review

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journal of Materials Science & Technology 2014年第6期30卷 523-545页

作者： j.C.qiao j.M.Pelletier Université de Lyon CNRS France INSA-Lyon MATEIS UMR5510 F-69621 Villeurbanne France

Metallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the mechanical, thermal properties and application of the metallic glasses. In addition, we focus on the dynamic mechanical relaxation behaviors, i.e. main （α） and secondary （β） relaxations, in metallic glasses. The mechanical relaxation behaviors are connected to the mechanical properties and physical properties in glassy materials. The main relaxation in glassy materials is related to the glass transition phenomenon and viscous flow. On the other hand, the β relaxation is linked to many fundamental issues in metallic glasses. In these materials relaxation processes are directly related to the plastic deformation mechanism. The mechanical relaxations, particularly, the β relaxation provides an excellent opportunity to design metallic glasses with desired physical and mechanical properties. We demonstrate the universal characteristics of main relaxation in metallic glasses. The phenomenological models and the physical theories are introduced to describe the main relaxation in metallic glasses. In parallel, we show the dependence of the α. and β relaxations on the thermal treatments in metallic glasses. Finally, we analyze the correlation between the atomic mobility and the thermo-mechanical treatments in metallic glasses. On the one hand, the atomic mobility in metallic glasses is reduced by physical aging or crystallization. On the other hand, the atomic mobility in metallic glass is enhanced by deformation （i.e. compression and cold rolling）. Importantly, to analyze the atomic mobility in amorphous materials, a physical theory is introduced. This model invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy materials.

关键词： Metallic glasses Mechanical properties Main relaxation Secondary relaxation Physical analysis