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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

Generation,bonding and reactivity of transient zinc-substituted silylenes

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Science China Chemistry 2024年第4期67卷 1256-1262页

作者： Cheng Xu Thayalan Rajeshkumar Laurent Maron Xuebing Leng yaofeng Chen State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Spin-X Institute School of Chemistry and Chemical EngineeringState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou 510641China LPCNO CNRS&INSAUniversitéPaul SabatierToulous 31077France

The metal-substituted silylenes are of high interest,as the theoretical studies indicated that the silylenes with electropositive substituents have a small ΔE_(S-T)(singlet-triplet energy gap)or even the ground-state ***,such compounds are highly unstable,and only two transient alkali metal-substituted silylenes M(^(t)Bu_(3)Si)Si:(M=Li,K)were generated by photoextrusion of the alkali metal-substituted silacyclopropenes and merely studied by spectroscopic method(EPR)at low temperature(14 to 50 K).Herein,we report the generation of transient zinc-substituted silylenes from zinc silacyclopropanyl complexes under very mild and convenient *** generated transient zinc-substituted silylenes are highly reactive and undergo intermolecular cycloaddition with alkenes for the synthesis of zinc-substituted Si-heterocyclic *** there is no substrate,the zinc-substituted silylenes attack the C-C bonds of the β-diketiminato ligands and break the C-C *** studies further highlight the silylene nature of the zinc-substituted silylene and a very small ΔE_(S-T)(4.4 kcal/mol).

关键词： zinc complex silylene C-C bond cleavage cycloaddition DFT calculations

Construct a 3D microsphere of HMX/B/Al/PTFE to obtain the high energy and combustion reactivity

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Defence Technology（防务技术） 2024年第2期32卷 45-54页

作者： Jian Wang Jie Chen yaofeng Mao Yongjun Deng Wei Cao Fude Nie Jun Wang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999PR China Shock and Vibration of Engineering Materials and Structures Key Lab of Sichuan Province Mianyang 621010PR China

Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy ***,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical ***,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion *** reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb *** to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 2..95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of *** reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2.O_(3) and B_(2.O_(3))and the initiation effect of Al to *** work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.

关键词： HMX/B/Al/PTFE 3D microspheres Surface etching Reaction mechanism

Electrochemical Dearomative Spirocyclization of N-Acyl Sulfonamides in a Continuous-Flow Cell

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Chinese Journal of Chemistry 2024年第9期42卷 980-984页

作者： Ting Liu Zhaojiang Shi yaofeng Yuan Yuqi Lin Ke-Yin Ye Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou University FuzhouFujian350108China

The development of efficient and sustainable methods to obtain spirocyclic compounds is of significance as these structures are widely found in pharmaceuticals and ***,we disclose an electrochemical dearomative spirocyclization of N-acyl sulfonamides in a continuous-flow *** reaction is simple and efficient without external catalysts or supporting electrolytes and could be applied in a decagram-scale synthesis.

关键词： Electrochemistry Continuous-flow Dearomatization Spirocyclization Sulfonamides Cyclization Methodology and reactions

Synthesis and Properties of Ferrocene Conjugated Macrocycles with Illusory Topology of the Penrose Stairs

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Chemical Research in Chinese Universities 2024年第5期40卷 881-886页

作者： XU Jindong LAN Bin ZHU Lingyun XU Hui CHEN Xinyu LI Wenjuan YUAN yaofeng YAN Jianfeng LI Yuanming Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108P.R.China Henan Key Laboratory of Biomolecular Recognition and Sensing College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu476000P.R.China

Polyferrocene macrocycles hold immense potential in the fields of molecular electronics and electrochemistry,primarily due to their multiple metal ***,developing highly efficient synthetic strategies for constructing these rings remains a significant *** this study,we successfully synthesized triferrocenyl macrocycles using Pt-mediated coupling strategy and determined their configuration using single-crystal X-ray diffraction analysis,revealing a structure reminiscent of the Penrose *** comprehensively investigated the macrocycle’s structure,photophysical properties,and employed density functional theory(DFT)calculations to gain further ***,this macrocycle exhibits several advantageous features,including a flexible structure,good solubility,and a highly efficient synthetic pathway.

关键词： Conjugated macrocycle Organometallic macrocycle Pt-template method

Influence of axial stress on rockburst in deep tunnels: insight from model experiment

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Journal of Mountain Science 2024年第10期21卷 3536-3551页

作者： YAN yaofeng XIA Yuanyou HUANG Jian LIN Manqing LIU Xiqi YAN Minjia ZHANG Hongwei School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China School of Resources and Safety Engineering Wuhan Institute of TechnologyWuhan 430074China Key Laboratory of Geotechnical and Structural Engineering Safety of Hubei Province School of Civil EngineeringWuhan UniversityWuhan 430000China China Railway 11th Bureau Group Fourth Engineering Co. Ltd.Wuhan 430074China School of Resource and Environment Sciences Wuhan UniversityWuhan 430000China

Frequent rockburst disasters in deep-buried engineering projects severely impact construction. To explore the influence of axial stress on rockburst in deep-buried tunnels, large-scale true triaxial rockburst experiments were conducted under four different axial stress ratio conditions (ηt, axial loading stress/vertical loading stress) using a self-developed true triaxial loading device under the condition of "pre-loading before excavation". The influence of axial stress on the rockburst process and failure characteristics in deep tunnels was studied using a combination of real-time video monitoring, rockburst debris sieving, and acoustic emission monitoring. The results indicate: (1) all four specimens subjected to different axial stress ratio loading conditions exhibited three stages of macroscopic failure: small particle ejection, flake spalling, and large fragment ejection. Ultimately, "V"-shaped notches appeared on both sides of the tunnel. (2. The failure stress, fragment volume, and fragment size distribution of the rockburst specimens exhibited a clear two-stage failure characteristic with increasing axial stress ratio. In the lower axial stress ratio stage (ηt ≤ 0.7), the increase in the axial stress ratio enhances lateral confinement, thereby increasing the crack initiation strength of the surrounding rock, inhibiting crack formation and propagation, and thus suppressing damage to the surrounding rock of the tunnel. In the higher axial stress ratio stage (ηt > 0.7), the increase in axial stress ratio makes the Poisson effect of the surrounding rock more pronounced, promoting the generation and propagation of cracks along the tunnel axis direction, thereby promoting damage to the surrounding rock. (3) Based on the analysis of acoustic emission parameters (fracture properties), it can be concluded that in the lower axial stress ratio stage (ηt ≤ 0.7), an increase in the axial stress ratio leads to a higher proportion of shear fracture in rockburst damage. Co

关键词： Rockburst experiments Axial stress ratio Failure characteristics Fracture properties

人事考试与档案管理融合策略及其预期效益研究

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山西档案 2024年第7期 167-170页

作者：高耀峰忻州市人事考试中心忻州034099

人事考试与档案管理是人力资源管理的重要组成部分。人事考试在人才选拔、促进人力资源优化配置等方面发挥着关键作用,而档案管理则为人事考试及整个人力资源管理提供重要的信息支撑。在梳理人事考试与档案管理理论基础的前提下,分析了... 详细信息

人事考试与档案管理是人力资源管理的重要组成部分。人事考试在人才选拔、促进人力资源优化配置等方面发挥着关键作用,而档案管理则为人事考试及整个人力资源管理提供重要的信息支撑。在梳理人事考试与档案管理理论基础的前提下,分析了两者融合的现实需求,并从信息化建设、管理制度创新、人力资源耦合、建立双轨多元管理体系以及应用大数据技术等多个维度,探讨了人事考试与档案管理的融合策略,同时,还对融合后的预期效益进行了全面分析,旨在为新形势下人事考试与档案管理工作优化提供参考思路,为推动我国人力资源管理工作的科学化、规范化、现代化水平提升作出积极贡献。

关键词：人事考试档案管理融合策略人力资源管理效益分析

何以携手共进:新型农业经营主体带动下农户回应的机制研究

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社会发展研究 2024年第2期11卷 169-187,M0006页

作者：李耀锋广东工业大学法学院

发挥新型农业经营主体带动小农户的作用是我国农村产业扶贫与产业振兴的关键。既有研究和实践重视探讨新型农业经营主体对小农户的带动方式与政策机制,但对农户如何回应关注不够,这不利于产业扶贫向产业振兴的转型升级。农户对新型农业... 详细信息

发挥新型农业经营主体带动小农户的作用是我国农村产业扶贫与产业振兴的关键。既有研究和实践重视探讨新型农业经营主体对小农户的带动方式与政策机制,但对农户如何回应关注不够,这不利于产业扶贫向产业振兴的转型升级。农户对新型农业经营主体的回应,反映了农户在一定的经济与社会结构中,基于自身利益诉求和资源条件与新型农业经营主体之间的认知、应答、认同及博奔的互动实践。基于江西S县产业扶贫实践的研究发现,农户回应有其自身实践逻辑,当农户回应乏力时,新型农业经营主体的产业带动作用会无法充分发挥。因此,乡村振兴背景下需充分尊重小农户的主体性,立足农户需求,提升产业带动的协同性与实效性,精准助推农村产业振兴与共同富裕。

关键词：新型农业经营主体小农户农户回应协同发展产业振兴

基于连续双脉冲测试的GaN HEMT动态导通电阻变化及测量方法

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半导体技术 2024年第10期49卷 920-925页

作者：陈耀峰国家电投集团河北电力有限公司石家庄050000

实际应用中,GaN HEMT的动态导通电阻会随着工作电压、工作温度等因素的变化而改变,相同温度下的实际值常与静态测量结果有所差异。由于实验条件及测量方法不同,同一型号的器件往往会出现不一致的测试结果,对应用工况的设计与监测带来了... 详细信息

实际应用中,GaN HEMT的动态导通电阻会随着工作电压、工作温度等因素的变化而改变,相同温度下的实际值常与静态测量结果有所差异。由于实验条件及测量方法不同,同一型号的器件往往会出现不一致的测试结果,对应用工况的设计与监测带来了困难。针对这一问题,提出了基于连续双脉冲的测试方法,并提出了一种基于差分计算的动态导通电阻提取方法,以更准确地提取器件的动态导通电阻。进一步讨论了母线电压和温度对器件动态导通电阻的影响,当母线电压增大时,GaN HEMT的动态导通电阻表现出先增大后减小的非单调的变化特性,动态导通电阻的标准值基本不随温度变化而改变。最后,探究了GaN HEMT动态导通电阻变化的机理,进一步加深了对器件动态导通电阻变化的理解。

关键词： GaN HEMT 动态导通电阻连续双脉冲测试差分计算机理分析

Side-Chain Type Ferrocene Macrocycles

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Precision Chemistry 2024年第4期2卷 143-150页

作者： Bin Lan Jindong Xu Lingyun Zhu Xinyu Chen Hideya Kono Peihan Wang Xin Zuo Jianfeng Yan Akiko Yagi Yongshen Zheng Songhua Chen yaofeng Yuan Kenichiro Itami Yuanming Li Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou 350108China Institute of Transformative Bio-Molecules(WPI-ITbM) Nagoya UniversityNagoya 464-8602Japan School of Materials Science and Engineering National Institute for Advanced MaterialsNankai UniversityTianjin 300350China Institute of Transformative Bio-Molecules(WPIITbM) Nagoya UniversityNagoya 464-8602Japan College of Chemistry and Material Science Longyan UniversityLongyan 364012China

A class of side-chain type ferrocene macrocycles with a radially conjugated system is introduced in this *** stereo configurations of these ferrocene rings were determined through single-crystal X-ray diffraction ***,in the solid state,the ferrocene rings exhibit a distinctive herringbone stacking pattern imposed by a ferrocene-to-ring host−guest *** UV−vis absorption spectroscopy,electrochemical measurements,and theoretical calculations,valuable insights into the electronic properties of these rings were *** addition,the single crystal of macrocycle A_(2.B demonstrates a second-order nonlinear optical *** a class of organometallic nanorings,this work holds great potential for further exploration in the fields of organometallic chemistry,molecular electronics,and host−guest chemistry.

关键词： Ferrocene Conjugated Macrocycles Organometallic Macrocycles Second-Order Nonlinear Optical Nanoring