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集美大学学报（自然科学版） 2024年第3期29卷 262-270页

作者：常雪尔孔庆钊王婉婷集美大学理学院福建厦门361021

为了更准确直观地刻画信息粒,从数字描述的角度,研究可变论域信息表中信息粒和粗糙集的个数,以及信息粒空间和粗糙集空间的基、维数等数字特征。

关键词：信息粒可变论域粗糙集数字特征

Effects of cerium addition on the microstructure and stress rupture properties of a new nickel-based cast superalloy

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journal of Materials Science & Technology 2023年第28期159卷 112-124页

作者： Lirong Rong Min wang Weiwei Xing Xianchao Hao Yingche Ma School of Materials Science and Engineering University of Science and Technology of Chin1Shenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The microstructure and stress rupture properties of a new nickel-based cast superalloy were investigated with the cerium(Ce)additions of 0,19,50,96,150,and 300 ppm,*** results indicated that Ce was mainly found in M C and M 23 C 6 carbides,and it was also found to exist in the form of cerium-rich phases or *** to the microstructure evidence,Ce promoted the formation of M C carbides and aggravated the inhomogeneity of M 23 C 6 carbides along grain *** was also identi-fied that the average sizes of primary and secondaryγ’phases all decreased with the rising Ce *** acceleration of Ti,Nb,and C segregations during solidification was attributed to the influence of cerium on the variation of carbides along grain *** stress rupture life experienced a signifi-cant drop as the Ce content increased from 19 to 300 *** showed that the degradation was mainly attributed to the severe degradation of M C carbides and the easily forming micro-voids around them caused by the Ce *** addition to that,the increments in the inhomogeneous distribution of M 23 C 6 carbides at grain boundaries and the accelerated coarsening rate ofγ’phases both induced the fracture under complex stress conditions.

关键词： Nickel-based cast superalloy Cerium MC carbide Stress rupture properties

A comprehensive study on the oxidation behavior and failure mechanism of(γ’+β)two-phase Ni-34Al-0.1Dy coating treated by laser shock processing

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journal of Materials Science & Technology 2023年第31期162卷 131-144页

作者： Bangyang Zhou Qijie Zhou jian He Wei wang Hongbo Guo School of Materials Science and Engineering Beihang University(BUAA)Beijing 100191China Research Institute for Frontier Science Beihang University(BUAA)Beijing 100191China Key Laboratory of High-Temperature Structural Materials&Coatings Technology(Ministry of Industry and Information Technology) Beihang University(BUAA)Beijing 100191China State Key Laboratory of Long-Life High Temperature Materials Deyang 618000China Dongfang Electric Corporation Dongfang Turbine Co. LTDDeyang 618000China

Laser shock processing(LSP),as a novel surface modification technology,exhibits tremendous potential to improve the oxidation resistance of *** this paper,(γ’+β)two-phase Ni-34Al-0.1Dy coatings were prepared by electron beam physical vapor deposition(EB-PVD)and then treated by LSP with different pulse energy(4 and 5 j).Their oxidation behavior(including isothermal oxidation and cyclic oxidation)at 1150°C was *** the isothermal oxidation case,the LSP-treated samples exhibited good ox-idation resistance due to high dislocation density and refined grains caused by the *** the cyclic oxidation,however,the LSP-treated samples were subjected to undesirable thermally grown oxide(TGO)*** the early oxidation stage(within 30 min),the residual compressive stress introduced by the LSP rapidly released,resulting in a severe plastic deformation at the coating/TGO *** a result,the mismatch between coating and TGO gave rise to the TGO *** the increase in the oxida-tion time,work hardening,which continuously limited the synchronous deformation of the TGO/coating interface,became the dominant mechanism controlling the TGO spallation of 5 j-treated *** continuous TGO spallation affected the Al supply and thus deteriorated the cyclic oxidation behavior.

关键词： Ni-34Al-0.1dy coating Laser shock processing Mechanical properties Oxidation Spallation

A general strategy towards improving the strength and thermal shock resistance of glass-ceramics through microstructure regulation

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journal of Materials Science & Technology 2022年第25期120卷 139-149页

作者： Min Feng Chengyang jiang Minghui Chen Shenglong Zhu Fuhui wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China Chinese Academy of Sciences Institute of Metal ResearchShenyang 110016China

Glass-ceramics are usually obtained through controlled *** this work,we propose a new strategy to add an appropriate amount of oxide particles to the parent glass to improve the performance of *** amounts of Al_(2)O_(3) or/and CeO_(2) particles were added into a SiO_(2)-Al_(2)O_(3)-ZnOCaO-ZrO_(2)-TiO_(2)based glass,and crystallization behavior,fracture strength,and thermal shock behavior were systematically *** results indicate that with the addition of Al_(2)O_(3) or/and CeO_(2) particles of moderate amount,the unfavorable needle-like ZrSiO_(4),Zn 2 SiO_(4),and CaTiSiO_(5) crystals were largely inhibited when annealed at 900℃ .Accordingly,fracture strength is maintained high after heating at high *** thermal shock resistance is also enhanced *** additive Al_(2)O_(3) is thermodynamically favorable to react with the glass,forming particulate ZnAl_(2)O_(4) instead of precipitating the needle-like crystals of Zn_(2)SiO_(4) and CaTiSiO_(5);while CeO_(2) will combine with ZrO_(2) to form a solid solution and promote the precipitation of primary crystal CaZrTi_(2)O_(7) that will not transform to ZrSiO_(4) with prolonging thermal exposure.

关键词： Non-metallic glasses(silicates) Crystallization Microstructure Mechanical property High-temperature oxidation

影响合肥市河流水质的生境多样性关键因素研究

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园林 2024年第6期41卷 12-22页

作者：潘晶葛俊雯汪洁琼上海翡世景观设计咨询有限公司上海200031 高密度人居环境生态与节能教育部重点实验室水绿生态智能分实验中心上海200092 同济大学建筑与城市规划学院上海200092 自然资源部大都市区国土空间生态修复工程技术创新中心上海200003

针对当下城市河流修复缺乏物理空间生境研究的知识缺口,面向生态文明建设与国土空间生态修复的国家战略需求,从提升生态系统服务综合效能的角度出发,通过学科交叉,定量揭示影响城市河流水质的生境多样性关键因素。以合肥市南淝河、塘西... 详细信息

针对当下城市河流修复缺乏物理空间生境研究的知识缺口,面向生态文明建设与国土空间生态修复的国家战略需求,从提升生态系统服务综合效能的角度出发,通过学科交叉,定量揭示影响城市河流水质的生境多样性关键因素。以合肥市南淝河、塘西河作为实证研究案例,通过水质实验与天空地生境信息采集获取样本数据,依据水质评价与URS生境多样性评价体系的研究方法,揭示水质与生境多样性之间的相关性,发现了同时对水质与生境多样性产生影响的关键因素。产生正向显著影响的指标分别为河岸自然化形态比例、河道生境类型数量、滨水带种植宽度、河岸乔木连续性指数、水生植被平均覆盖度、主导水生植物类型、水生植物长势、河岸植被特征指数;产生负向显著影响的指标为河岸带植被相关特征、河岸表层植被平均高度、固定河床材料比例、护岸存在比例、河岸材质指数、主导护岸材质类型、护岸材质指数、入河排污口数量。这些关键因素可作为城市河流生态修复重点关注的生境指标,为基于生境多样性恢复的城市河流生态修复提供一定的理论依据与技术支撑。

关键词：风景园林城市河流生态修复水质生境多样性合肥市

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Rotating magnetocaloric effect and thermal transport properties in sintered Nd0.8Pr0.2Co5 alloy

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journal of Rare Earths 2020年第6期38卷 606-611页

作者： Mingxiao Zhang Kun wang jian Liu Lei Liu Aru Yan CAS Key Laboratory of Magnetic Materials and Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology.Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China

We report microstructure,magnetocaloric effect and thermal transfer properties of highly orientated Nd0.8Pr0.2Co5 alloy prepared by powder metallurgical *** spin-reorientation transitions of easy magnetization direction,easy plane to easy cone at TSR1=206 K,easy cone to easy axis at TSR2=242 K,are *** present textured alloy exhibits a rotating entropy change of 2.6 j/(kg·K)and refrigerant capacity of 155 j/kg under a magnetic field of 2 T,and high thermal conductivity of 11 W/(m·K).The sintered Nd0.8Pr0.2Co5 alloy with good combination of excellent magnetocaloric and thermal transfer properties are promising for scientific research and practical applications as room-temperature rotating magnetic refrigeration materials.

关键词： Rotating magnetocaloric effect Rare-earth alloys Anisotropy Spin-reorientation

Analysis of oil shedding and ligaments formation on bearing rotary elements

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Chinese journal of Aeronautics 2023年第2期36卷 377-387页

作者： Donglei ZHU Guoding CHEN Yanjun LI Chaoyang ZHANG Lin wang School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China China Gas Turbine Establishment Chengdu 610500China

For designing efficient lubrication system of an aeroengine bearing chamber,sufficient knowledge on oil/air two-phase flow characteristics is *** analyzing bearing chamber two-phase flow,the essential prerequisite is quantifying the oil ligaments,which are detached from bearing rotary elements and shed into the bearing *** investigations are mainly targeted at liquid shedding on the rotating disk as opposed to the bearing rotary ***,the research based on bearing rotary elements is conducted by *** to the limited operating conditions,experimental studies cannot guide engineering *** overcome these limitations,a theoretical model is established in this paper,for revealing the mechanism of oil shedding from bearing rotary elements and quantifying the shedding *** theoretical model is validated against experimental results from classical *** addition,the correlation for shedding ligaments number based on aeroengine bearing structural and operational parameters is obtained via theoretical *** analytical results demonstrate that oil shedding and ligaments formation appear at the edge of bearing inner race *** number of shedding ligaments increases with the rise of shaft rotational speed while decreases with the growth of oil viscosity.

关键词： Aeroengine bearing chamber Ligaments Lubrication Mechanical analysis Shedding Wave

Pilot multi-axis control behavior modeling of receivers in probe-and-drogue aerial refueling

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Science China(Technological Sciences) 2022年第1期65卷 87-101页

作者： wang LiXin LU Chang ZHAO Peng LIU HaiLiang YUE Ting School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China China Flight Test Establishment Xi'an 710089China

The probe-and-drogue aerial refueling(PDR)task is seriously disturbed by the wind field,so it is difficult to obtain accurate visual information of the probe and drogue ***,the pilot needs to control the vertical,lateral and forwardbackward positions of the receiver through the stick and throttle lever,and the pitch and roll manipulation actions of the stick should be reasonably *** simulate the behavior of the pilot’s visual perception and the stick manipulation allocation in the PDR task,three modules are designed,including the visual information acquisition module(VIAM),strategy switching module(SSM)and pilot control and action module(CAM).Based on the coherence function analysis of the flight simulation test data,it is proven that the pilot’s multi-axis control behavior can be decoupled,and the flight states to be controlled are ***,the established multi-axis receiver pilot model(EPM)is *** with the motion models of the receiver,the tanker and the refueling equipment,a PDR flight task simulation model is established,and the evaluation indicators for the receiver’s flight performance during the PDR task,such as capture time and settling time,are *** PDR flight simulation model was used to build the ground-based flight simulation test platform,and the flight simulation test of the PDR task was carried out.A comparison between the flight simulation test data and the numerical simulation results shows that the calculation error is less than 10%,which verifies the correctness of the established pilot *** pilot model can be used to evaluate the design scheme of the refueling equipment and the receiver flight control law and provide a theoretical reference for the flight test design of the PDR task.

关键词： pilot modeling aerial refueling discrete-time model flight simulation

Local thermal conductivity of polycrystalline AlN ceramics measured by scanning thermal microscopy and complementary scanning electron microscopy techniques

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Chinese Physics B 2012年第1期21卷 374-379页

作者： Zhang Yue-Fei wang Li R.Heiderhoff A.K.Geinzer Wei Bin ji Yuan Han Xiao-Dong L.j.Balk Zhang Ze Institute of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100124China Department of Electronics Faculty of ElectricalInformation and Media EngineeringUniversity of WuppertalWuppertal D-42119Germany Department of Materials Science Zhejiang UniversityHangzhou 300038China

The local thermal conductivity of polycrystalline aluminum nitride （A1N） ceramics is measured and imaged by using a scanning thermal microscope （SThM） and complementary scanning electron microscope （SEM） based techniques at room temperature. The quantitative thermal conductivity for the A1N sample is gained by using a SThM with a spatial resolution of sub-micrometer scale through using the 3w method. A thermal conductivity of 308 W/m-K within grains corresponding to that of high-purity single crystal A1N is obtained. The slight differences in thermal conduction between the adjacent grains are found to result from crystallographic misorientations, as demonstrated in the electron backscattered diffraction. A much lower thermal conductivity at the grain boundary is due to impurities and defects enriched in these sites, as indicated by energy dispersive X-ray spectroscopy.

关键词： thermal conductivity A1N ceramics scanning thermal microscopy scanning electronmicroscopy

Alleviatory effect of rare earth micro-fertilizer on photosystemⅡ(PSⅡ)photoinhibition in Pseudostellaria heterophylla leaves at photosynthetic midday depression

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journal of Rare Earths 2022年第7期40卷 1156-1164页

作者： Yingli Ma Tao wang Yinfeng Xie Qian Lv Lingling Qiu Co-Innovation Center for Sustainable Forestry in Southern China College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China jiangsu Key Laboratory for the Research and Utilization of Plant Resources Institute of BotanyJiangsu Province and Chinese Academy of Sciences(Nanjing Botanical Garden Mem.Sun Yat-Sen)Nanjing 210014China

In order to explo re the mitigatory mechanism of rare earths on the midday depression of photosynthesis,this study used fast-phase chlorophyll fluorescence technology combined with an antioxidant enzyme system to analyze the effects of lanthanum and cerium on the photosystemⅡ(PSⅡ)function of Pseudostellaria heterophylla leaves at *** results show that the maximum photochemical efficiency(F_(v)/F_(m))and the photosynthetic performance index(PI_(ABS))of *** leaves during the photo synthetic noon-break are only 0.73 and 0.86,*** leaves of *** show obvious *** application of two rare earth fertilizers promotes the light energy absorption,capture,conversion,and electron transfer efficiencies of PSⅡin the *** leaves and alleviates the photoinhibition caused by excess excitation ***,the effect of lanthanum is better than that of *** the fertilization groups,*** leaves show higher PSⅡphotochemical *** protects the oxygen-evolving complex(OEC)activity of ***,thus reducing oxidative damage to the chloroplasts and preventing the dissociation of the thylakoids to maintain the normal physiological functioning of PSⅡ,thereby reducing the degree of ***,fertilization increases the electron transfer ability from Q_(A) to Q_(B) on the PSⅡelectron receptor side of *** analysis shows that the fluorescence parameters V_(L),V_(K),and V_(j) are significantly negatively correlated with antioxidant enzyme activity and are significantly positively correlated with malondialdehyde content,relative electric conductivity and reactive oxygen species(ROS),which further indicates that rare earths can enhance the ROS scavenging system in plants and reduce the degree of membrane lipid peroxidation and plasma membrane damage,thereby maintaining the structure and function of the OEC on the donor side of PSⅡ,increasing the elect

关键词： Pseudostellaria heterophylla Rare earths Photoinhibition jIP-test Antioxidant enzyme system