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Strengthening mechanism and forming control of linear friction welded GH4169 alloy joints

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Chinese Journal of Aeronautics 2024年第4期37卷 609-626页

作者： Yu SU Xiawei YANG Tingxi meng Xinyuan HE Dong WU Wenya LI shuo YIN State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Friction Welding Technologies School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Manufacturing and Biomedical EngineeringParsons BuildingTrinity College DublinThe University of DublinDublin 2Ireland

Numerical simulation and experimental research on Linear Friction Welding(LFW) for GH4169 superalloy were carried out. Based on the joint microstructure and mechanical properties,a suitable welding process was determined, which provided an important theoretical basis for the manufacture and repair of aeroengine components such as the superalloy blisk. The results show that the joint strain rate gradually increases with the increase of welding frequency, and the deformation resistance of the thermoplastic metal increases in the welding process, resulting in the interface thermoplastic metal not being extruded in time to form a flash, so the joint shortening amount gradually decreases. The thermoplastic metal in the center of the welding surface is kept at high welding temperature for a long time, resulting in the decrease of the joint strength. The microhardness of the joint shows a “W” distribution perpendicular to the weld, and most of the joints break in the Thermo-Mechanically Affected Zone(TMAZ) with high tensile strength and low *** the welding area is increased without changing the aspect ratio of the welding surface, the interface peak temperature increases gradually, and the joint shortening amount decreases with the increase of the welding interface size.

关键词： Linear Friction Welding(LFW) Microstructure Mechanical properties Numerical simulation Joint shortening amount

A 658-W VCSEL-pumped rod laser module with52.6% optical efficiency

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Chinese Physics B 2022年第8期31卷 149-153页

作者： Xue-Peng Li Jing Yang meng-shuo Zhang Tian-Li Yang Xiao-Jun Wang Qin-Jun Peng Key Laboratory of Solid State Laser Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Functional Crystal and Laser Technology Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Institute of Optical Physics and Engineering Technology Qilu ZhongkeJinan 250000China University of Chinese Academy of Sciences Beijing 100190China

A high-efficiency and high-power vertical-cavity surface-emitting laser(VCSEL) side-pumped rod Nd:YAG laser with temperature adaptability are demonstrated. The VCSEL side-pumped laser module is designed and optimized. Five VCSEL arrays are symmetrically located around the laser rod and a large size diffused reflection chamber is designed to ensure a uniform pump distribution. Furthermore, the absorbed pump power distribution of the rod is simulated to verify the uniformity of the pump absorption. Finally, a proof-of-principle experiment is performed in short linear cavity laser with single laser module. A continuous-wave output power of 658 W at 1064 nm is obtained, the corresponding optical-to-optical efficiency is 52.6%, and the power variations are ±0.7% over 400 s and ±3.1% over the temperature range from 16 ℃ to 26 ℃. To the best of our knowledge, this is the highest output power and the highest optical-to-optical efficiency ever reported for VCSEL pumped solid-state lasers. By inserting a telescopic module into the cavity and optimizing the TEM_(00) mode volume, the average beam quality is measured to be M~2= 1.34 under an output power of 102 W. The experimental results reveal that such a high power rod laser module with temperature stability is appropriate for field applications.

关键词： rod laser VCSEL-pumped high-efficiency temperature adaptability

Effect of linear friction welding process on microstructure evolution,mechanical properties and corrosion behavior of GH4169 superalloy

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Chinese Journal of Aeronautics 2024年第6期37卷 504-520页

作者： Yu SU Xiawei YANG Tingxi meng Dong WU Rui XU Haiyu XU Wenya LI shuo YIN State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Manufacturing&Biomedical EngineeringParsons BuildingTrinity College DublinThe University of DublinDublin 2Ireland

Linear Friction Welding(LFW)technology was used to realize the welding of GH4169 superalloy,and the effect of welding parameters on the microstructure,mechanical properties and corrosion behavior of the joint was *** results show that there is a positive correlation between the weld hardness and the tensile *** the gradual increase of heat input and welding pressure,the joint quality is gradually improved,but the heat affected zone is not significantly *** smaller the grain size of the weld,the higher the strength and plasticity of the *** the increase of the joint shortening amount,the corrosion resistance of the weld first gradually ***,when the shortening reaches a certain level,the corrosion resistance of the joint becomes little *** the increase of solution temperature,the corrosion current density increases and the polarization impedance *** higher the corrosion temperature,the worse the corrosion resistance of the *** is no significant correlation between the joint strength and the corrosion *** corrosion resistance of the joint can be enhanced without changing the joint mechanical properties by reducing the welding frequency and amplitude or increasing the welding pressure.

关键词： Linear Friction Welding(LFW) GH4169 superalloy Microstructure Mechanical properties Corrosion behavior

Illuminating spin-crossover octanuclear metal-organic cages

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Science China Chemistry 2024年第4期67卷 1208-1215页

作者： Zhi-Kun Liu Alyona A.Starikova Yu-Xia Li Ke Sun meng Yu Zi-shuo Yao Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Institute of Physical and Organic Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical *** this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO *** them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity *** also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first *** calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission.

关键词： metal-organic cages spin crossover fluorescence switching materials DFT calculation

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巢湖流域生物多样性评估指标体系构建

湿地科学与管理 2024年第4期20卷 27-31页

作者：傅海峰刘萌硕姚亦鹏武舒阳袁一波安树青南京大学常熟生态研究院南大(常熟)研究院有限公司江苏苏州215501 南京大学生命科学学院江苏南京210046

生物多样性评价是生物多样性保护与管理的基础。本研究基于压力-状态-响应(PSR)模型框架,构建了14个流域尺度指标以及23个生态系统尺度指标的巢湖流域生物多样性评价指标体系。该指标体系可全面反映生物多样性状态、变化、威胁和决策等... 详细信息

生物多样性评价是生物多样性保护与管理的基础。本研究基于压力-状态-响应(PSR)模型框架,构建了14个流域尺度指标以及23个生态系统尺度指标的巢湖流域生物多样性评价指标体系。该指标体系可全面反映生物多样性状态、变化、威胁和决策等综合因素的影响,为评估巢湖流域等长江中下游地区山水林田湖草系统保护修复成效、优化生物多样性保护策略提供指导。评价结果显示:2022年巢湖流域水环境一级保护区内湖泊、湿地生态系统的生物多样性水平均处于较高级别,系统反映了近10年巢湖的综合治理成效。

关键词：生物多样性巢湖流域 PSR模型尺度

Comparison between total laparoscopy and laparoscopy assisted distal gastrectomy for gastric cancer:a meta-analysis

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Comparison between total laparoscopy and laparoscopy assiste...

Preparation and up-conversion luminescence of Ho3+/Yb3+ codoped glass ceramic containing SrF2

第9届全国胃癌学术会议暨第二届阳光长城肿瘤学术会议

作者： shuo-meng Xiao Ling-chao Tang Ping Zhao Zhi Ding Division of Gastrointestinal Surgery Department of Surgical OncologySichuan Cancer Hospital and Institute

Objective:With surgeons experience accumulated and anastomotic equipments improved,total laparoscopy distal gastrectomy was *** performed a meta-analysis to assess the safety and feasibility of total laparoscopy distal ***:The meta-analysis was conducted from April to July 2013 in Si Chuan Cancer Hospital,Chengdu,*** searched PUBMED,EMBASE and CNKI（China Knowledge Resource Inergrated Database）updated to May 10,*** retrospective studies and one prospective study involving 2046 patients were ***:The meta-analysis results showed total laparoscopy distal gastrectomy had less blood loss,more lymph nodes *** was no significant difference between the two groups in operation time,time to first flatus,postoperative hospital stay and postoperative ***:Compared with laparoscopy assisted distal gastrectomy,total laparoscopy distal gastrectomy reduced blood loss and harvested more lymph *** laparoscopy distal gastrectomy is safe,feasible for gastric cancer.

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Preparation and up-conversion luminescence of Ho3+/Yb3+ codo...

Electro-assisted photocatalytic reduction of CO_(2) in ambient air using Ag/TNTAs at the gas-solid interface

中国化学会2019年中西部地区无机化学化工学术研讨会

作者： Zhang Hongbo meng shuo Zou Xiangyu Shao Jing Su Chunhui College of Chemistry and Environmental Engineering Changchun University of Science and Technology Changchun Normal University

Ho-Ybco-doped transparent glass ceramics containing SrF crystals with the weight percentage composition of 25SrCO-11AlO-34SiO-11HBO-2TiO-17NaF-1.1HoO-y YbO were successfully synthesized using high temperature melting quenching *** structure,morphology and luminescent properties of the samples were measured and characterized by X-ray diffraction (XRD),scanning electron microscope (SEM),Ultraviolet-visible-Near Infrared (UV-Vis-NIR) spectra,and fluorescence *** results show that the optimum heat treatment temperature is 630℃,the optimum heat treatment tine is 3 h,and the transparency of the samples is 75%.The effect of Ho-Ybco-doped glass ceramics with different doping concentrations of Ybon the up-conversion luminescence properties was *** optimum doping concentration ratio of Ho-Ybis 1:*** green light (538nm) and weak red light (656 nm) were observed in the luminescence *** energy transfer process between Hoand Ybwas *** mechanism of the green emission and red emission were studied,and the result showed that both are two photon absorption *** mechanism of the green emission and red emission were studied,and the result showed that both are two photon absorption process.

关键词： SrF2 glass ceramics Ho3+-Yb3+ co-doped up-conversion

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Materials Reports(Energy) 2024年第2期4卷 71-82页

作者： Feng Yue Zhaoya Fan Cong Li Yang meng shuo Zhang mengke Shi Minghua Wang Mario Berrettoni Jun Li Hongzhong Zhang Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration Zhengzhou University of Light IndustryZhengzhou450001PR China Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou450052PR China Department of Chemistry University of CamerinoCamerino62032MacerataItaly

The direct conversion of atmospheric CO_(2) into fuel via photocatalysis exhibits significant practical application value in advancing the carbon *** this study,we established an electro-assisted photocatalytic system with dual compartments and interfaces,and coated Ag nanoparticles on the titanium nanotube arrays(TNTAs)by polydopamine *** the absence of sacrificial agent and alkali absorption liquid conditions,the stable,efficient and highly selective conversion of CO_(2) to CO at the gas-solid interface in ambient air was realized by photoelectric ***,with the assistance of potential,the CO formation rates reached 194.9μmol h^(−1) m^(−2) and 103.9μmol h^(−1) m^(−2) under ultraviolet and visible light irradiation,respectively;the corresponding CO_(2) conversion rates in ambient air were 30%and 16%,*** excellent catalytic effect is mainly attributed to the formation of P–N heterojunction during the catalytic process and the surface plasmon resonance ***,the introduction of solid agar electrolytes effectively inhibits the hydrogen evolution reaction and improves the electron utilization *** system promotes the development of photocatalytic technology for practical applications and provides new insights and support for the carbon cycle.

关键词： Electro-assisted photocatalytic Gas-solid interface Ambient air P–N heterojunction Practical applications

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日本博士毕业生的就业困境及其破解之策

黑龙江高教研究 2021年第10期39卷 61-66页

作者：孟硕洋东京大学教育学研究科大学日本东京都113-0033

日本博士规模在1990年代快速扩大以后,由于缺乏足够的学术职业,日本出现了严重的博士毕业生就业问题。为改善这一问题,日本政府通过改革博士教育、加强就业引导等方法,积极推动博士人才进入企业就业。随着我国博士人才队伍规模不断扩大... 详细信息

日本博士规模在1990年代快速扩大以后,由于缺乏足够的学术职业,日本出现了严重的博士毕业生就业问题。为改善这一问题,日本政府通过改革博士教育、加强就业引导等方法,积极推动博士人才进入企业就业。随着我国博士人才队伍规模不断扩大,日本应对博士毕业生就业问题的经验值得我国参考。

关键词：日本博士毕业生就业困境破解策略