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International Journal of Minerals,Metallurgy and Materials 2023年第6期30卷 1190-1197页

作者： Fuyuan Liang Jiaran Yang Haiqing Wang Junwei wu School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

Physical vapor deposition(PVd)can be used to produce high-quality Gd_(2)O_(3)-doped CeO2(GdC)*** various PVd methods,reactive sputtering provides unique benefits,such as high deposition rates and easy upscaling for industrial *** thin films were successfully fabricated through reactive sputtering using a Gd_(0.2)Ce_(0.8)(at%)metallic target,and their application in solid oxide fuel cells,such as buffer layers between yttria-stabilized zirconia(YSZ)/La0.6Sr0.4Co0.2Fe0.8O_(3−δ)and as sublayers in the steel/coating system,was ***,the direct current(dC)reactive-sputtering behavior of the GdCe metallic target was ***,the GdC films were deposited on NiO-YSZ/YSZ half-cells to investigate the influence of oxygen flow rate on the quality of annealed GdC *** results demonstrated that reactive sputtering can be used to prepare thin and dense GdC buffer layers without high-temperature ***,the cells with a sputtered GdC buffer layer showed better electrochemical performance than those with a screen-printed GdC buffer *** addition,the insertion of a GdC sublayer between the SUS441 interconnects and the Mn-Co spinel coatings contributed to the reduction of the oxidation rate for SUS441 at operating temperatures,according to the area-specific resistance tests.

关键词： solid oxide fuel cell physical vapor deposition Gd2O3-doped CeO_(2) metallic interconnects electrical conductivity

the Synthesis of 19-Nor-1a , 25-dihydroxy-22-oxo-vitamin d_(3)

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Chinese Chemical Letters 2001年第1期12卷 19-20页

作者： Yong wu Mei GUAN Pei Jie LI Cheng XU Xiao Chun wu School of Pharmacy West China University of Medical SciencesChengdu 610041 the First Hospital West China University of Medical SciencesChengdu 610041

Nor-1α, 25-dihydroxy-22-oxo-vitamin d3 4 was synthesized by the coupling of known compound 5 and the A-ring phosphine oxide 6 followed by deprotection of the hydroxy functions.

关键词： Nor-1α 25-dihydroxy-22-oxo-vitamin d3 device synthest

Effect of anisotropic resistance characteristic on boundary-layer transitional flow

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Applied Mathematics and Mechanics(English Edition) 2022年第12期43卷 1935-1950页

作者： Zheng HONG Zhengyin YE Kangling wu Kun YE National Key Laboratory of Science and technology on Aerodynamic design and Research Northwestern Polytechnical UniversityXi'an 710072China

It is observed that the feather surface exhibits anisotropic resistances for the streamwise and spanwise *** obtain a qualitative understanding about the effect of this anisotropic resistance feature of surface on the boundary-layer transitional flow over a flat plate,a simple phenomenological model for the anisotropic resistance is established in this *** means of the large eddy simulation(LES)with high-order accurate finite difference method,the numerical investigations are *** numerical results show that with the spanwise resistance hindering the formation of vortexes,the transition from laminar flow to turbulent flow can be delayed,and turbulence is weakened when the flow becomes fully turbulent,which leads to significant drag reduction for the *** the contrary,the streamwise resistance renders the flow less stable,which leads to the earlier transition and enhances turbulence in the turbulent region,causing a drag increase for the ***,it is indicated that a surface with large resistance for spanwise flow and small resistance for streamwise flow can achieve significant drag *** present results highlight the anisotropic resistance characteristic near the feather surface for drag reduction,and shed a light on the study of bird’s efficient flight.

关键词： anisotropic resistance transitional flow drag reduction numerical simulation

Early Hydration and Setting Process of Fly Ash-blended Cement Paste under different Curing temperatures

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Journal of wuhan University of technology(Materials Science) 2020年第3期35卷 551-560页

作者： ZHANG Wenhua wu Fan ZHANG Yunsheng Civil Engineering department Nanjing Forestry UniversityNanjing 210037China department of Materials Science and Engineering Southeast UniversityJiangsu Key Laboratory of Construction MaterialsNanjing 211189China

A specially developed ultrasonic measurement apparatus (UMA) was used to in situ monitor the setting process of fly ash blended cement paste. Combined with the results of Vicat Needle tests, isothermal calorimetric measurement, XRd analysis, SEM morphology and compressive test, the influence of curing temperature (20, 40, 60, and 90 ℃) and fly ash content (0,10%, 20% and 30%) on the setting and hydration process of fly ash blended cement paste was analyzed. the results show that setting and hardening process of fly ash blended cement paste at elevated temperature can be clearly identified into three stages including dormant stage, acceleration stage and deceleration stage. the increasing of curing temperature greatly accelerates the setting and hardening process. However, the content of fly ash does not have significant effect on the setting in condition of 90 ℃. Besides, the initial and final setting time of cement paste is correspondent with the time of duration of dormant stage and the time of UPV value is 1500 m/s (t1500), respectively. thus, the UMA can be used to determine the initial and final setting time of cementitious material under different curing temperatures. the compressive test results indicate that the paste with 20% fly ash presents higher compressive strength than the plain paste at curing temperatures of 90 ℃. therefore, appropriate amount of fly ash is beneficial for concrete in the high temperature curing conditions.

关键词： ultrasonic setting and hardening process curing temperature fly ash microstructure

Achieving ultra-high strength in Mg-Gd-Ag-Zr wrought alloy via bimodal-grained structure and enhanced precipitation

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Journal of Materials Science & technology 2020年第19期54卷 160-170页

作者： Yu Zhang Wei Rong Yujuan wu Liming Peng College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Engineering Research Centre of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Mg-13.1 Gd-1.6 Ag-0.4 Zr(wt%)alloy was either iso-thermally extruded at 350℃ or differentialthermally extruded with respectively pre-heated billet at 500℃ and die at 350℃.the iso-thermal extrusion leads to a near fully recrystallized structure and a[0001]//Ed(extrusion direction)*** contrast,the differential-thermally extruded alloy develops a bimodal-grained structure composed of fine equiaxed recrystallized grains and coarse elongated unrecrystallized grains with a0110//Ed *** differential-thermally extruded alloy has a higher number density of precipitates after postextrusion ageing than that of the iso-thermally extruded ***,precipitation in the differential-thermally extruded alloy is further enhanced with cold rolling before ***,the alloy obtains room temperature tensile yield strength of 421 MPa and ultimate tensile strength of 515 MPa via differential-thermal extrusion,cold rolling and ageing,mainly ascribed to the coupled strengthening from the bimodal-grained structure and enhanced *** of the alloy is noticeably higher than those of Mg-Gd(-Y)-Ag extruded alloys with similar compositions reported previously and is comparable to those of other high-strength Mg wrought *** findings suggest that differentialthermal extrusion plus strain ageing is a suitable approach for achieving high strength in age-hardenable Mg alloys.

关键词： Mg alloy Extrusion Bimodal-grained structure Precipitation Electron back scattering diffraction

台兰河流域地下水人工回补适宜性评价及试验验证

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节水灌溉 2024年第4期 11-18页

作者：付龙浩吴彬杜明亮赵忠贤高星新疆农业大学水利与土木工程学院乌鲁木齐830052 新疆水利工程安全与水灾害防治重点实验室乌鲁木齐830052 新疆兵团勘测设计院集团有限公司乌鲁木齐830052

地下水人工回补是管理含水层、调蓄水资源的重要方法,探究合理的适宜性评价方法是确定回补区域的基本工作。利用遥感数据和GIS技术,基于直觉模糊层次分析法(IFAHP),构建GIS-IFAHP决策模型,选取地下水位埋深、给水度、土壤质地、含水层... 详细信息

地下水人工回补是管理含水层、调蓄水资源的重要方法,探究合理的适宜性评价方法是确定回补区域的基本工作。利用遥感数据和GIS技术,基于直觉模糊层次分析法(IFAHP),构建GIS-IFAHP决策模型,选取地下水位埋深、给水度、土壤质地、含水层渗透系数、地形坡度、土地利用/覆盖、与灌区距离、河网密度8个指标进行主观层次排序,获得各指标的综合主观权重,结合加权叠加分析法得到研究区地下水人工回补适宜性分区图,并在高适宜区内做地表入渗试验,分析地下水回补的可行性。结果表明:地下水回补低适宜区主要分布在细土平原区,占回补区总面积13.24%;中等适宜区主要分布在砾质平原中下部,占回补区面积29.48%;高适宜区主要位于砾质平原区中上部,占回补区总面积18.94%。地表渗库8 d内共回补水量1.54万m^(3),回补期间3眼观测孔水位平均稳定在14.95 m,地下水位平均累积抬升25.21 m。采用GIS-IFAHP决策模型,在地下水回补区域选择合理性上表现良好;干旱地区土地利用率较低且回补条件良好的倾斜砾质平原,通过地表入渗回补的方式能够有效地补充地下水。

关键词：地下水回补适宜性评价 GIS-IFAHP决策模型适宜性分区回补试验台兰河流域

A novel electron-phonon coupling thermoelasticity with Burgers electronic heat transfer

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1927-1940页

作者： Hua wu Xinyi LI Yajun YU Zichen dENG School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China MIIt Key Laboratory of dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China

the electron-phonon interaction can reveal the microscopic mechanism of heat transfer in *** two-step heat conduction considering electron-phonon interaction has become an effective theoretical model for extreme environments,such as micro-scale and ultrafast *** this work,the two-step heat transfer model is further extended by considering the Burgers heat conduction model with the secondorder heat flux rate for ***,a novel generalized electron-phonon coupling thermoelasticity is proposed with the Burgers electronic heat ***,the problem of one-dimensional semi-infinite copper strip subject to a thermal shock at one side is studied by the Burgers two-step(BtS)*** thermoelastic analytical solutions are systematically derived in the Laplace domain,and the numerical Laplace inversion method is adopted to obtain the transient *** new model is compared with the parabolic two-step(PtS)model and the hyperbolic two-step(HtS)*** results show that in ultrafast heating,the BtS model has the same wave front jump as the HtS *** present model has the faster wave speed,and predicts the bigger disturbed regions than the HtS *** deeply,all two-step models also have the faster wave speeds than one-step *** work may benefit the theoretical modeling of ultrafast heating of metals.

关键词： Burgers heat transfer electron-phonon coupling two-step generalized thermoelasticity

Facile Preparation of NiO@graphene Nanocomposite with Superior Performances as Anode for Li-ion Batteries

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Acta Metallurgica Sinica(English Letters) 2022年第2期35卷 212-222页

作者： Junke Ou Shugen wu Lin Yang Hao Wang Institute for Advanced Study Chengdu UniversityChengdu 610106China Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong 643000China Zhanglan Honors College Chengdu UniversityChengdu 610106China School of Medicine Chengdu UniversityChengdu 610106China School of Mechanical Engineering Chengdu UniversityChengdu 610106China

transition metal oxides gain considerable research attentions as potential anode materials for lithium ion batteries,but their applications are hindered due to their poor electronic conductivity,weak cycle stability and drastic volume ***,a NiO@graphene composite with a unique 3d conductive network structure is prepared through a simple *** applied as anode material for Li-ion batteries,at 50 mA g^(−1),the NiO@graphene displays a high reversible capacity of 1366 mAh g^(−1) and a stable cyclability of 205 mAh g^(−1) after 500 *** at a high rate of 10 A g^(−1),it displays a favorable reversible capacity of 711 mAh g^(−1).Remarkably,when it recovers back to 0.05 A g^(−1),a reversible capacity of 1741 mAh g^(−1) is ***,the NiO@graphene composite with 3d structure shows good application prospects as an alternative anode for advanced lithium ion batteries.

关键词： Lithium ion batteries 3d conductive network structure NiO@graphene composite Alternative

Mechanism of interconnected synchronized switch damping for vibration control of blades

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Chinese Journal of Aeronautics 2023年第8期36卷 207-228页

作者： Yu FAN Yu HU Yaguang wu Lin LI School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Aero-engine Structure and Strength Beijing 100191China Sino-French Engineering School Beihang UniversityBeijing 100191China

the Synchronized Switch damping(SSd)is regarded as a promising alternative to mitigate the vibration of thin-walled structures in aero-engines,especially for blades or bladed *** common manner is to shunt the switch circuit independently to a single piezoelectric *** paper is aimed at exploring a novel way of using the SSd,i.e.,the SSd is interconnected between two piezoelectric structures or *** damping mechanism,performance,and effective range of the interconnected SSd are studied numerically and ***,based on a dual cantilever beam finite element model,the time domain and frequency domain modeling and solving methods of the interconnected SSd are deduced and ***,the influence of the amplitude and phase relationship on the damping effect of the interconnected SSd is numerically studied and compared with the shunted SSd.A self-sensing SSd control board is developed,and experimental studies are carried *** results show that the interconnected SSd establishes an additional energy channel between the corresponding piezoelectric *** the amplitudes of the two cantilever beams are different,the interconnected SSd balances the vibration level of each *** the amplitudes of the two cantilever beams are the same,if the appropriate interconnection manner is selected according to the phase,the resonance peak can be reduced by more than 30%.When the vibration is in-phase/out-of-phase,the damping generated by the interconnected SSd in a cross/parallel manner is even more significant than the shunted ***,this novel connection scheme reduces the number of SSd circuits in ***,for engineering applications,we implement the proposed damping technology to the finite element model of a typical dummy bladed disk.A piezoelectric damping ratio of 13.7%is achieved when the amount of piezo material is only 10%of blade *** with traditional friction dampers,the major advancements of t

关键词： Blade dry friction damping Experiments Finite element method Piezoelectric Synchronized switch damping

High-temperature fatigue crack propagation study of superalloy GH4169 by single-lens 3d digital image correlation

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Science China(technological Sciences) 2020年第4期63卷 693-704页

作者： YIN YuanJie HE Wei XIE HuiMin wu LiFu Key Laboratory of Applied Mechanics School of Aerospace EngineeringTsinghua UniversityBeijing 100084China

the characterization of fatigue crack propagation behavior is crucial for performance and reliability evaluation of aerospace *** this study,high-temperature(maximum:650℃)fatigue crack propagation experiments of Ni-based superalloy GH4169 were *** bi-prism-based single-lens 3d digital image correlation(BSL 3d dIC)technique was used to insitu measure the displacement and strain fields near fatigue crack *** on the deformation information,the modeΙstress intensity factor range△K and the crack opening displacement(COd)were determined for characterizing the crack closure *** the major fatigue crack growth model,the parameters of modified Paris’law were obtained based on the effective stress intensity factor range△Keff and the fatigue crack propagation rate(FCPR).Additionally,two kinds of J integrals,JP(path integral method)and JK(stress intensity factor K method),were used to evaluate the small-scale yielding approximation.

关键词： high-temperature fatigue Paris'law crack closure BSL 3d dIC