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Improvement of titanium alloy TA19 fatigue life by submerged abrasive waterjet peening:Correlation of its process parameters with surface integrity and fatigue performance

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Chinese Journal of Aeronautics 2024年第1期37卷 377-390页

作者： Gongyu WANG Shulei YAO Yuxin CHI Chengcheng ZHANG Ning WANG Yalong CHEN Rongsheng LU Zhuang LI Xiancheng ZHANG Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China AECC Commercial Aircraft engine Co.LTD Shanghai Engineering Research Center for Commercial Aircraft EngineShanghai 201108China

Submerged abrasive waterjet peening(SAWJP)is an effective anti-fatigue manufacturing technology that is widely used to strengthen aeroengine *** study investigated the correlation of SAWJP process parameters on surface integrity and fatigue life of titanium alloy *** with different water pressures and standoff distances(SoDs)was conducted on the TA19 *** surface integrity of the specimens before and after SAWJP with different process parameters was experimentally studied,including microstructure,surface roughness,microhardness,and compressive residual stress(CRS).Finally,fatigue tests of the specimens before and after SAWJP treatment with different process parameters were carried out at room *** results highlighted that the fatigue life of the TA19 specimen can be increased by 5.46,5.98,and 6.28 times under relatively optimal process parameters,which is mainly due to the improved surface integrity of the specimen after SAWJP ***,the fatigue life of specimens treated with improper process parameters is decreased by 0.55 to 0.69 times owing to the terrible surface roughness caused by the material *** work verifies that SAWJP can effectively improve the surface integrity and fatigue life of workpieces,and reveals the relationship between process parameters,surface integrity,and fatigue life,which provides support for the promotion of SAWJP in the manufacturing fields.

关键词： Fatigue testing Process parameters Submerged abrasive waterjet peening Surface integrity Surface treatment Titanium alloy TA19

Active Magnetic Compensation Based on Parametric Resonance Magnetometer

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Journal of shanghai Jiaotong university(Science) 2024年第2期29卷 280-289页

作者：郭阳李绍良黄艺明骆曼箬刘华 School of Electronic Information and Electrical engineering Shanghai Jiao Tong UniversityShanghai 200240China shanghai Institute of spacefight Control technology Shanghai Key Laboratory of Space Intelligent Control TechnologyShanghai Engineer Research Center of InertiaShanghai 201109China

Based on the parametric resonance magnetometer(PRM)theory,this paper establishes an experimen-tal system of *** experimental results are consistent with the theoretical predictions.A PRM has been developed with sensitivity of 0.5 pT/Hz^(1/2),which can detect the magnitude of residual magnetic field;furthermore,a proportion-integration-differentiation(PID)closed-loop magnetic compensation system of the residual magnetic field also has been *** with open-loop compensation,the PID closed-loop compensation reduces the average value of the residual magnetic field in the z-axis direction from 0.0244nT to-0.0023nT,and the mean-square error from 0.2083 nT to 0.0691 *** the same way,the average value of the residual magnetic field in the y-axis direction is reduced from 0.0816nT to-0.0042nT,and the mean-square error from 0.1316nT to 0.0461 *** magnitude of residual magnetic fields in both directions is decreased to the order of picotesla(pT).In addition,based on the signal waveforms of the magnetometer,a method of verifying the effect of magnetic compensation is proposed.

关键词： magnetometer parametric resonance nuclear magnetic resonance gyroscope magnetic compensa-tion proportion-integration-differentiation(PID)

Wind Turbine Gearbox Fault Diagnosis Based on Multi-sensor Signals Fusion

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Protection and Control of Modern Power Systems 2024年第4期9卷 96-109页

作者： Yao Zhao Ziyu Song Dongdong Li Rongrong Qian Shunfu Lin the College of Electrical engineering Shanghai University of Electric PowerShanghai 200090China IEEE the Design research and Development center AECC Commercial Aircraft engine Co. Ltd.Shanghai 200241China

This paper proposes a novel fault diagnosis method by fusing the information from multi-sensor signals to improve the reliability of the conventional vibration-based wind turbine drivetrain gearbox fault diagnosis *** method fully extracts fault features for variable speed,insufficient samples,and strong noise scenarios that may occur in the actual operation of a wind turbine planetary ***,multiple sensor signals are added to the diagnostic model,and multiple stacked denoising auto-encoders are designed and improved to extract the fault ***,a cycle reservoir with regular jumps is introduced to fuse multidimensional fault information and output diagnostic results in response to the insufficient ability to process fused information by the conventional Softmax *** addition,the competitive swarm optimizer algorithm is introduced to address the challenge of obtaining the optimal combination of parameters in the ***,the validation results show that the proposed method can increase fault diagnostic accuracy and improve robustness.

关键词： Wind turbine gearbox fault diagnosis multiple scenarios deep learning stacked denoising au-to-encoder cycle reservoir with regular jumps feature fusion network

Effects of rafting on the meso deformation and fracture behaviour of a Ni-based single crystal superalloy at room temperature: In-situ observation and simulation

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Science China(Technological Sciences) 2024年第7期67卷 2133-2146页

作者： TAN Long YANG XiaoGuang SHI DuoQi FAN YongSheng SHI Yi School of Energy and Power engineering Beihang UniversityBeijing 102206China research Institute of Aero-engine Beihang UniversityBeijing 102206China National Key Laboratory of Science and technology on Aero-engine Aero-Thermodynamics Beihang UniversityBeijing 102206China School of Materials Science&engineering Shanghai Jiao Tong UniversityShanghai 200240China

Microstructural rafting of Ni-based single-crystal(SC) superalloys is inevitable at elevated temperatures during long-term service with mechanical loading, which significantly affects the mechanical behaviour of the material. In this study, the effects of rafting on the mesodeformation and fracture behaviour of a Ni-based SC superalloy under cyclic and tensile loads were investigated using in situ scanning electron microscopy(SEM), digital image correlation(DIC), and crystal plasticity finite element method(CP-FEM) simulations. The results indicated that the tensile strength decreased significantly in the rafted specimens. In the cyclic tests, both the virgin and rafted specimens showed an increase in the maximum shear strain with cycle number. The interaction of cross-slip bands was captured by in situ SEM-DIC around the micro-notch of the virgin specimens during the tensile test, while a more homogeneous local deformation field was observed in the rafting specimens. In addition,the fracture behaviour was strongly influenced by the rafting morphology. The crack exhibited instantaneous and long-range fracture features along the octahedral plane as it propagated in the rafting specimen, whereas it deflected over a short distance between the crystallographic planes at an early stage in the virgin specimen, which is consistent with the CP-FEM ***, the CP-FEM results for the crack initiation direction on(111) dominant slip plane were consistent with the in situ SEM observations.

关键词： in-situ SEM-DIC Ni-based SC superalloys microstructural rafting deformation crack path CP-FEM

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Metal-free two-dimensional phosphorene-based electrocatalyst with covalent P-N heterointerfacial reconstruction for electrolyte-lean lithium-sulfur batteries

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Carbon Energy 2024年第5期6卷 175-185页

作者： Jiangqi Zhou Chengyong Shu Jiawu Cui Chengxin Peng Yong Liu Weibo Hua Laura Simonelli Yuping Wu Shi Xue Dou Wei Tang School of Chemical engineering and technology Xi'an Jiaotong UniversityXi'anChina School of Materials Science and engineering University of Shanghai for Science and TechnologyShanghaiChina State Key Laboratory of space Power-Sources technology Shanghai Institute of Space Power-SourcesShanghaiChina CELLS-ALBA Synchrotron BarcelonaSpain School of Energy and Environment Southeast UniversityNanjingChina

The use of lithium-sulfur batteries under high sulfur loading and low electrolyte concentrations is severely restricted by the detrimental shuttling behavior of polysulfides and the sluggish kinetics in redox ***-dimensional(2D)few layered black phosphorus with fully exposed atoms and high sulfur affinity can be potential lithium-sulfur battery electrocatalysts,which,however,have limitations of restricted catalytic activity and poor electrochemical/chemical *** resolve these issues,we developed a multifunctional metal-free catalyst by covalently bonding few layered black phosphorus nanosheets with nitrogen-doped carbon-coated multiwalled carbon nanotubes(denoted c-FBP-NC).The experimental characterizations and theoretical calculations show that the formed polarized P-N covalent bonds in c-FBP-NC can efficiently regulate electron transfer from NC to FBP and significantly promote the capture and catalysis of lithium polysulfides,thus alleviating the shuttle ***,the robust 1D-2D interwoven structure with large surface area and high porosity allows strong physical confinement and fast mass ***,with c-FBP-NC as the sulfur host,the battery shows a high areal capacity of 7.69 mAh cm^(−2) under high sulfur loading of 8.74 mg cm^(−2) and a low electrolyte/sulfur ratio of 5.7μL mg^(−1).Moreover,the assembled pouch cell with sulfur loading of 4 mg cm^(−2) and an electrolyte/sulfur ratio of 3.5μL mg^(−1) shows good rate capability and outstanding *** work proposes an interfacial and electronic structure engineering strategy for fast and durable sulfur electrochemistry,demonstrating great potential in lithium-sulfur batteries.

关键词： black phosphorus electronic structure high sulfur loading interfacial covalent bonds lean electrolyte

Sub-Nyquist radar receiver based on photonics-assisted compressed sensing and cascaded dictionaries

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Chinese Optics Letters 2024年第1期22卷 159-163页

作者：刘诗扬陈阳 shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghai 200241China engineering center of SHMEC for space Information and GNSS East China Normal UniversityShanghai 200241China

A sub-Nyquist radar receiver based on photonics-assisted compressed sensing is *** dictionaries are applied to extract the delay and the Doppler frequency of the echo signals,which do not need to accumulate multiple echo periods and can achieve better Doppler *** experiment is *** echoes with different delays and Doppler frequencies are undersampled and successfully reconstructed to obtain the delay and Doppler information of the *** results show that the average reconstruction error of the Doppler frequency is 5.33 kHz using an 8-μs radar signal under the compression ratio of *** proposed method provides a promising solution for the sub-Nyquist radar receiver.

关键词： compressed sensing dictionary learning sub-Nyquist radar microwave photonics Doppler frequency

Growth of ablative Rayleigh-Taylor instability induced by time-varying heat-flux perturbation

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Matter and Radiation at Extremes 2024年第1期9卷 85-93页

作者： Yang Liu De-Hua Zhang Jing-Fei Xin Yudong Pu Jun Li Tao Tao Dejun Sun Rui Yan Jian Zheng Department of Modern Mechanics University of Science and Technology of ChinaHefei 230026China Deep space Exploration Laboratory Hefei 230026China Laser Fusion research center China Academy of Engineering PhysicsMianyang 621900China Institute of Applied Physics and Computational Mathematics Beijing 100094China Department of Plasma Physics and Fusion engineering University of Science and Technology of ChinaHefeiAnhui 230026China Collaborative Innovation center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China CAS center for Excellence in Ultra-intense Laser Science Shanghai 201800China

The evolution of ablative Rayleigh–Taylor instability(ARTI)induced by single-mode stationary and time-varying perturbations in heat flux is studied numerically in two *** with the stationary case,time-varying heat-flux perturbation mitigates ARTI growth because of the enhanced thermal smoothing induced by the wave-like traveling heat flux.A resonance is found to form when the phase velocity of the heat-flux perturbation matches the average sound speed in the ablation *** the resonant regime,the coherent density and temperature fluctuations enhance the electron thermal conduction in the ablation region and lead to larger ablation pressure and effective acceleration,which consequently yield higher linear growth rate and saturated bubble *** enhanced effective acceleration offers increased implosion velocity but can also compromise the integrity of inertial confinement fusion shells by causing faster ARTI growth.

关键词： perturbation stationary acceleration

Sandwich-type composited solid polymer electrolytes to strengthen the interfacial ionic transportation and bulk conductivity for all-solid-state lithium batteries from room temperature to 120℃

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Journal of Energy Chemistry 2024年第8期95卷 288-295,I0007页

作者： Jiewen Tan Zhen Wang Jiawu Cui Zhanhui Jia Wensheng Tian Chao Wu Chengxin Peng Chengyong Shu Kang Yang Wei Tang School of Chemical engineering and technology Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina center for Advancing Materials Performance from the Nanoscale(CAMP-Nano) State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049ShaanxiChina State Key Laboratory of space Power-sources technology Shanghai Institute of Space Power-SourcesShanghai 200245China School of Materials Science and engineering University of Shanghai for Science and TechnologyShanghai 200093China Top-Energy Digital Manufacturing Technologies(Xi'an)Co. Ltd.Xi'an 710100ShaanxiChina

The insurmountable charge transfer impedance at the Li metal/solid polymer electrolytes(SPEs)interface at room temperature as well as the ascending risk of short circuits at the operating temperature higher than the melting point,dominantly limits their applications in solid-state batteries(SSBs).Although the inorganic filler such as CeO_(2)nanoparticle content of composite solid polymer electrolytes(CSPEs)can significantly reduce the enormous charge transfer impedance at the Li metal/SPEs interface,we found that the required content of CeO_(2)nanoparticles in SPEs varies for achieving a decent interfacial charge transfer impedance and the bulk ionic conductivity in *** this regard,a sandwich-type composited solid polymer electrolyte with a 10%CeO_(2)CSPEs interlayer sandwiched between two 50%CeO_(2)CSPEs thin layers(sandwiched CSPEs)is constructed to simultaneously achieve low charge transfer impedance and superior ionic conductivity at 30℃.The sandwiched CSPEs allow for stable cycling of Li plating and stripping for 1000 h with 129 mV polarized voltage at 0.1 mA cm^(-2)and 30℃.In addition,the LiFePO_(4)/Sandwiched CSPEs/Li cell also exhibits exceptional cycle performance at 30℃and even elevated120℃without short *** multi-layered CSPEs with optimized contents of the inorganic fillers can be an efficient method for developing all solid-state PEO-based batteries with high performance at a wide range of temperatures.

关键词： PEO-based solid electrolytes CeO_(2)nanoparticles Charge transfer impedance Sandwich-type composite electrolytes All-solid-state Li metal batteries

Simultaneous transmission of time-frequency and data with co-amplification over urban fiber links

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Chinese Optics Letters 2024年第1期22卷 28-33页

作者：操前童周刘雷王家亮应康庞拂飞桂有珍 Key Laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information EngineeringShanghai UniversityShanghai 200444China Key Laboratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Key Laboratory of space Laser Communication and Detection technology Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China center of Materials Science and Optoelectronics engineering University of Chinese Academy of SciencesBeijing 100049China

We demonstrate a simultaneous transmission of time-frequency and data over a 160-km urban business network in *** signals are transmitted through a cascaded optical link consisting of 48 km and 32 km,which are connected by an optical *** metrological signals are inserted into the communication network using dense wavelength division *** influence of the interference between different signals has been *** experimental results demonstrate that the radio frequency(RF)instability can reach 2.1×10^(-14)at 1 s and 2.3×10^(-17)at 10,000 s,and the time interval transfer of one pulse per second(1 PPS)signal with less than 10 ps at 1 s is *** work paves the way for the widespread dissemination of ultra-stable time and frequency signals over the communication networks.

关键词： simultaneous transmission radio frequency transfer communication network wavelength multiplexing