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Quality assessment of friction-stir-welded aluminum alloy welds via three-dimensional force signals

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Advances in Manufacturing 2024年第1期12卷 61-75页

作者： Ji-Hong Dong Yi-Ming Huang Jia-Lei Zhu Wei Guan Xu-Kai Ren Huan-Wei Yu Lei Cui Beijing institute of Petrochemical Technology Beijing102617People’s Republic of China Beijing Academy of Safety Engineering and Technology Beijing102617People’s Republic of China AVIC Manufacturing Technology institute Beijing100024People’s Republic of China Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300350People’s Republic of China shaoxing special equipment testing institute Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071ZhejiangPeople’s Republic of China

An online detection technology must be developed for realizing the real-time control of friction stir *** this study,the three-dimensional force exerted on a material during friction stir welding was collected synchronously and the relationship between the forces and welding quality was *** results indicated that the fluctuation period of the traverse force was equal to that of the lateral force during the stable welding *** phase difference between two horizontal forces wasπ/*** values of the horizontal forces increased with welding speed,whereas their amplitudes remained the *** proposed force model showed that the traverse and lateral forces conformed to an elliptical curve,and this result was consistent with the behavior of the measured *** variational mode decomposition was used to process the plunge *** intrinsic mode function that represented the real fluctuation in the plunge force varied at the same frequency as the spindle rotational *** tunnel defects occurred,the fluctuation period features were consistent with those obtained during normal welding,whereas the ratio parameter defined in this study increased significantly.

关键词： Friction stir welding(FSW) Three-dimensional force model Variational mode decomposition Tunnel defect

Applications of Mass Spectrometry in Textile Analysis: An Overview

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Journal of Analysis and testing 2024年第4期8卷 518-537页

作者： Yudi Ruan Xianshuang Meng Jiangang Wang Hongwei Wang Qiong Ye Qianyi Shou Qiang Ma Chinese Academy of Inspection and Quarantine shaoxing testing institute of Quality and Technical Supervision

Mass spectrometry (MS) stands as a pivotal tool for chemical analysis in the textile industry, capable of scrutinizing the vast majority of reported harmful chemicals. With the ever-increasing number of banned chemicals in textiles, there is a pressing need for a more systematic compilation of relevant literature on MS utilization to identify and quantify harmful substances in textiles. This article comprehensively reviews the role of MS in textile analysis over the past two decades, encompassing a wide range of sample preparation techniques, such as energy-assisted extraction, solid-phase microextraction, liquid-phase microextraction, and QuEChERS. Furthermore, it delves into MS techniques, such as gas chromatography–MS, liquid chromatography–MS, inductively coupled plasma–MS, ion mobility spectrometry–MS, and ambient ionization MS. Moreover, it offers a brief glimpse into the future of MS development in this field, highlighting ongoing research into additional sample preparation techniques for detecting hazardous chemicals in textiles. Notably, it underscores the growing interest in ambient ionization MS and the coupling of chromatography with high-resolution MS.

关键词： Harmful chemicals Mass spectrometry Sample preparation Textiles

Synthesis of Polybutadienes with Controllable Microstructure by a Novel Binary Nd(3-NBSO_3)_3/Alkylaluminum Catalyst System

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Chinese Journal of Polymer Science 2015年第3期33卷 475-480页

作者： Ji-qin Wen Xue-quan Zhang 代全权 Key Laboratory of Synthetic Rubber Changchun Institute of Applied ChemistryChinese Academy of Sciences Jiangsu Province institute for Medical equipment testing

The polymerization of 1,3-butadiene was examined by using a novel halogen-free neodymium m-nitrobenzenesulfonate （Nd（3-NBSOa）3·donors）/alkylaluminum binary catalyst system. The catalyst showed fairly high activity and controllable selectivity. The microstructure of the resultant polymer was adjustable by variation of electron donor and/or the alkylaluminum. ^13C-NMR and thermal analysis demonstrate that the produced polybutadienes have stereo-block chain structures of cis-1,4 and trans-1,4 segments with adjustable Tm and To. The neodymium sulfonate-based catalyst is believed to be significant in regulating the chain structure of polydienes and in exploring 1,3-diene polymerization mechanism.

关键词： Polybutadiene Microstructure Ziegler-Natta polymerization.

A Parzen Window-based Approach to Detection of Infrared Dim Target Under Sea-sky Background

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International Journal of Automation and computing 2016年第5期13卷 447-456页

作者： He Deng Huang Yao Yan-Tao Wei Ji-Dong Chen Department of Information Technology Central China Normal University Wuhan 430079 China Wuhan institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430079 China shaoxing testing institute of Quality and Technical Supervision Shaoxing 312071 China

People attach great importance to high detection probability and low false alarm probability for infrared dim target detection. Consequently, a novel approach is proposed based on inverted local information entropy map and the improved region growing technique. The idea originates from the intrinsic property of natural image, the visual mechanism of flying insects and the information entropy theory. Besides qualitative analyses, other methods including the norms of local signal-to-background ratio, local signal-to-noise ratio, region non-uniformity, single-frame detection probability and single-frame false alarm probability are adopted to quantitatively evaluate the proposed approach. Both qualitative and quantitative comparisons confirm the validity and efficiency of the proposed approach.

关键词： Dim target detection information entropy Parzen window region growing visual mechanism.

Effect of stress profile on microstructure evolution of cold-drawn commercially pure aluminum wire analyzed by finite element simulation

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Journal of Materials Science & Technology 2018年第7期34卷 1214-1221页

作者： Y.K.Zhu Q.Y.Chen Q.Wang H.Y.Yu R.Li J.P.Hou Z.J.Zhang G.P.Zhang Z.F.Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences National Quality Supervision & Inspection Center of Electrical equipment Safety Performance Zhejiang Huadian Equipment Testing Institute

The evolution of microstructure in the drawing process of commercially pure aluminum wire （CPAW） does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress profile on the texture evolution of the CPAW was systematically investigated by combining the numerical simulation and the microstructure observation. The results show that the tensile stress at the wire center promotes the formation of 〈111〉 texture, whereas the shear stress nearby the rim makes little contribution to the texture formation. Therefore, the 〈111 〉 texture at the wire center is stronger than that in the surface layer, which also results in a higher microhardness at the center of the CPAW under axial loading.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Commercially pure aluminum wire Cold drawing Texture Finite element simulation Stress profile

Structures and catalytic performances of Me/SAPO-34(Me=Mn,Ni,Co)catalysts for low-tem perature SCR of NO_x by ammonia

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Journal of Environmental Sciences 2021年第6期33卷 137-149页

作者： Xuesong Liu Zhiming Sui Hongfeng Chen Yong Chen Haigang Liu Peng Jiang Zhongyun Shen Wensheng Linghu Xiaodong Wu College of Chemistry and Chemical Engineering Shaoxing UniversityShaoxing 312000China Key Laboratory of Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Zhejiang Hailiang Eco.Mater.Co. Ltd.Zhuji 311814China shaoxing testing institute of Quality and Technical Supervision Shaoxing 312000China Chemical Design and Research institute of Qinghai Province Xining 810008China

Me/SAPO-34(Me=Mn,Ni,Co)series of catalysts were prepared by a wetness impregnation method and investigated for the selective catalytic reduction of nitrogen oxides with ammonia(NH 3-SCR).Among them,Mn/SAPO-34 catalyst was found as the most promising candidate based on its superior low-temperature *** catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy images(TEM),nuclear magnetic resonance(NMR),X-ray photoelectron spectroscopy(XPS),temperature programmed reduction and desorption(TPR and TPD),and diffuse reflectance infrared Fourier transformed spectroscopy(DRIFTS)of NH_(3)/NO_(x)***/SAPO-34 is obviously different from Ni/SAPO-34 and Co/SAPO-34 in the active species state and *** MnO_(x)species which play an essential role in NO oxidation and NO_(2)adsorption,act as better active sites than nickel and cobalt mostly in the form of the aluminates and silicates.

关键词： SAPO-34 Transition metals Low-temperature activity Fast SCR Surface species

Damage Identification of General Overhead Travelling Crane Structure Based on Model Updating by Sensitivity

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第3期34卷 308-317页

作者： Qing Guangwei Yue Lin Guo Qingtao Tao Yanhe Hu Jingbo College of Mechanical and Electronical Engineering Nanjing University of Aeronautics and Astronautics Nanjing special equipment Inspection institute

A model based damage identification was proposed by facilitating parameter sensitivity analysis and applied to a general overhead travelling *** updating reference data,experimental modal frequency was obtained by operational modal analysis(OMA)under ambient *** dimensional damage function was defined to identify the damage by bending *** results showed that the model updating method could locate the damage and quantitatively describe the *** average error of eigenvalues between updated model analysis and the experimental results was less than 4% which proved the accuracy *** comparison of finite element analysis and the test results of the deflection under the capacity load further verified the feasibility of this method.

关键词： crane overhead operational updating verified deflection modal stiffness quantitatively bending

A quantitative research on the level of disturbance to secondary signal ports of electronic voltage transformers under the operation of gas‐insulated switchgear

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High Voltage 2022年第1期7卷 165-175页

作者： Qi Wang Chao Fu Fanwu Chu Yue Tong Xiaozhou Wang Guoxiong Ye Xiong Wu Power Industry Electrical equipment Quality Inspection and testing Center China Electric Power Research InstituteWuhanChina

The collectors of electronic transformers has the problem of electromagnetic in-compatibility under the operation of disconnecting switches,which limits their wide application in smart *** evaluate the maximum level of disturbance that collectors are able to withstand in the stochastic process of switching operation,this work in-troduces a quantitative approach based on limited test measurements,which can quantify the level of disturbance in the signal acquisition ports of electronic voltage transformers(EVT)in different gas‐insulated switchgears(GIS).Based on large numbers of experi-mental statistical data of the true type simulation experimental platform,the Spearman rank correlation coefficient is used to prove that the amplitude of the disturbance voltage pulse at the secondary side port and the breakdown voltage between the primary side fracture approximately satisfy a linear ***,the quantile regression model is used to quantify and verify the maximum disturbance level of the secondary side ***,a solution is proposed to tackle the difficulty in obtaining the breakdown voltage at breaks in the GIS substation field applicatvion,under which the quantified maximum disturbance voltage deviation of secondary ports is only−4.34%by *** research work can further explore the practical value of the measured data in a few tests under GIS substation field conditions and provide references for the sub-sequent revision of EVT‐related standards.

关键词： disturbance operation electronic

Microstructure and Properties of SiCp/Al Composite Materials Fabricated via Powder Packed Resistance Additive Manufacturing

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稀有金属材料与工程 2024年第11期53卷 3035-3045页

作者： Wang Wenqin Chen Jigen Yan Xiaosong Han Zhaoxian Lin Gang Chen Jie School of Mechanical and Electrical Engineering Nanchang UniversityNanchang 330031China institute of special equipment Inspection and Research Jiangxi General Institute of Testing and CertificationNanchang 330029China Jiangxi Sinohexaco Helicopter Co. LtdJingdezhen 333032China Jiangxi Haoyu Heavy Industry Co. LtdRuijin 341000China

SiC particle(SiCp)/Al composite materials were fabricated via powder packed resistance seam welding additive *** influence of welding speed on microstructure and mechanical properties of the specimen was investigated,elucidating the formation and fracture mechanism of single-pass multi-layer *** results demonstrate that a dense internal structure of the specimen characterized by uniformly dispersed SiCp embedded within the Al matrix is ***,particle agglomeration and porosity defects are *** porosity increases with the increase in welding speed,and the microstructure of the RSAM-24 specimen has the highest density,characterized by a density of 2.706 g/cm^(3)and a porosity of 1.672%.The mechanical properties of the specimens decrease as the welding speed *** mechanical properties are obtained when the welding speed is set as 24 cm/***,the average hardness,tensile strength and elongation values are 463.736 MPa,52.16 MPa and 2.2%,*** tensile specimens predominantly exhibit fracture along the interlayer bonding interface and the interface between the Al matrix and SiC particles,and the damage mode is ductile fracture.

关键词： additive manufacturing resistance seam welding SiCp/Al hardness welding speed