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Preliminary Investigation on Zhuang Folk Medicated Bath Prescriptions:A Case Study of Hechi Region
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作者 Junmiao MO wenya li +2 位作者 Jianyu MO Haicheng WEN Wei WEI 《Plant Diseases and Pests》 CAS 2023年第2期27-28,35,共3页
This paper summarizes the mechanism,methods and characteristics of Zhuang folk medicated bath,as well as the composition and application of prescriptions,which provides a basis for the popularization of Chinese ethnic... This paper summarizes the mechanism,methods and characteristics of Zhuang folk medicated bath,as well as the composition and application of prescriptions,which provides a basis for the popularization of Chinese ethnic medicine. 展开更多
关键词 Zhuang folk prescription Medicated bath Medicated bath prescription
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Effects of Nitrogen Addition on the Mixed Litter Decomposition in Stipa baicalensis Steppe in Inner Mongolia 被引量:1
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作者 wenya li Wenchao Yu +2 位作者 Long Bai Hongmei liu Dianlin Yang 《American Journal of Plant Sciences》 2016年第3期547-561,共15页
During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three differ... During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three different plant species tissues (Stipa baicalensis: Sb, Leymus chinensis: Lc and Artemisia frigid: Af), endemic to Stipa baicalensis Steppe, and measured the mass loss of mixtures over 417 days under the N addition treatment. We studied the effect of N addition (N0: no N addition;N15: 1.5 g N/m<sup>2</sup>·a;N30: 3.0 g N/m<sup>2</sup>·a;N50: 5.0 g N/m<sup>2</sup>·a;N100: 10.0 g N/m<sup>2</sup>·a;N150: 15.0 g N/m<sup>2</sup>·a) on the rate of mixed litter decomposition and nutrient dynamics change. The decomposition constant (k) of leaf mixtures was higher than that of root mixtures. The k values of leaf mixed combinations were 0.880 (Sb + Lc), 1.231 (Lc + Af), 1.027 (Sb + Lc + Af), respectively. The k value of stem was 0.806 (Lc + Af) and the root mixed combinations were 0.665 (Sb + Lc), 0.979 (Lc + Af) and 1.164 (Sb + Lc + Af), respectively. The results indicated that N addition had significantly effect on the mixed litter decomposition and nutrient releasing. The rate of plant tissues litter decomposition had different response to N addition. In the context of N addition, litter decomposition rate and nutrient dynamics were changed by synthetic effect of decaying time, specie types and N addition dose. Our findings suggested that prairie plants may adapt to environmental change by adjusting litter quality, thus retaining the stability of the steppe ecosystem. 展开更多
关键词 GRASSLAND Litter Decomposition Mixed Effect N Addition Mass Loss Nutrient Dynamics
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Mars Ion and Neutral Particle Analyzer (MINPA) for Chinese Mars Exploration Mission (Tianwen-1): Design and ground calibration 被引量:4
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作者 lingGao Kong AiBing Zhang +15 位作者 Zhen Tian XiangZhi Zheng WenJing Wang Bin liu Peter Wurz Daniele Piazza Adrian Etter Bin Su YaYa An JianJing Ding wenya li Yong liu Lei li YiRen li Xu Tan YueQiang Sun 《Earth and Planetary Physics》 CSCD 2020年第4期333-344,共12页
The main objective of the Mars Ion and Neutral Particle Analyzer(MINPA)aboard the Chinese Mars Exploration Mission(Tianwen-1)is to study the solar wind-Mars interaction by measuring the ions and energetic neutral atom... The main objective of the Mars Ion and Neutral Particle Analyzer(MINPA)aboard the Chinese Mars Exploration Mission(Tianwen-1)is to study the solar wind-Mars interaction by measuring the ions and energetic neutral atoms(ENAs)near Mars.The MINPA integrates ion and ENA measurements into one sensor head,sharing the same electronics box.The MINPA utilizes a standard toroidal top-hat electrostatic analyzer(ESA)followed by a time of flight(TOF)unit to provide measurement of ions with energies from 2.8 eV to 25.9 keV and ENAs from 50 eV to 3 keV with a base time resolution of 4 seconds.Highly polished silicon single crystal substrates with an Al2O3 film coating are used to ionize the ENAs into positive ions.These ions can then be analyzed by the ESA and TOF,to determine the energy and masses of the ENAs.The MINPA provides a 360°×90°field of view(FOV)with 22.5°×5.4°angular resolution for ion measurement,and a 360°×9.7°FOV with 22.5°×9.7°angular resolution for ENA measurement.The TOF unit combines a-15 kV acceleration high voltage with ultra-thin carbon foils to resolve H+,He2+,He+,O+,O2+and CO2+for ion measurement and to resolve H and O(≥16 amu group)for ENA measurement.Here we present the design principle and describe our ground calibration of the MINPA. 展开更多
关键词 MARS ION energetic neutral atom electrostatic analyzer time of flight
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Modeling the Jovian magnetosphere under an antiparallel interplanetary magnetic field from a global MHD simulation 被引量:1
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作者 YuXian Wang XiaoCheng Guo +2 位作者 BinBin Tang wenya li Chi Wang 《Earth and Planetary Physics》 2018年第4期303-309,共7页
We present preliminary results of a new global Magnetohydrodynamics(MHD) simulation model of the Jovian magnetosphere.The model incorporates mass loading from Jupiter's satellite Io, the planet's fast corotati... We present preliminary results of a new global Magnetohydrodynamics(MHD) simulation model of the Jovian magnetosphere.The model incorporates mass loading from Jupiter's satellite Io, the planet's fast corotation, and electrostatic coupling between its magnetosphere and ionosphere(M-I coupling). The basic configuration of the Jovian magnetosphere including the equatorial plasma flow pattern, the corotation enforcement current system, and the field aligned currents(FACs) in the ionosphere are presented under an antiparallel interplanetary magnetic field(IMF) condition. The simulation model results for equatorial density and pressure profiles are consistent with results from data-based empirical models. It is also found that there are similarities between the FACs distribution in the ionosphere and the observed aurora features, showing the potential application of the simple ionospheric model to the complicated M-I coupling. This model will help deepen our understanding of the global dynamics of the Jovian magnetosphere. 展开更多
关键词 JUPITER MAGNETOSPHERE magnetohydrodynamic(MHD)simulation
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Proton pitch angle distributions in the Martian induced magnetosphere: A survey of Tianwen-1 Mars Ion and Neutral Particle Analyzer observations
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作者 TaiFeng Jin BinBin Ni +14 位作者 lingGao Kong AiBing Zhang Lei li Song Fu Xing Cao wenya li BinBin Tang liangHai Xie YiTeng Zhang ShuYue Pang XiaoTong Yun HengLe Du FuHao Qiao liMin Wang JiJie Ma 《Earth and Planetary Physics》 CAS CSCD 2023年第5期533-539,共7页
The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations... The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations from the Mars Ion and Neutral Particle Analyzer onboard the Tianwen-1 orbiter,we calculated the pitch angle distributions of protons in the Martian induced magnetosphere by using information from the magnetohydrodynamically simulated magnetic field,and we statistically analyzed the spatial occurrence pattern of different types of pitch angle distributions.Even though no symmetrical features were seen in the dataset,we found the dominance of the field-aligned distribution type over the energy range from 188 to 6232 eV.Maps of the occurrence rate showed the preferential presence of a trapped-like distribution at the lower altitudes of the surveyed nightside region.Although our results are more or less restricted by the adopted magnetic field,they indicate the complexity of the near-Mars proton pitch angle distributions and infer the possibility of wave–particle interactions in the Martian induced magnetosphere. 展开更多
关键词 Martian plasma environment ion pitch angle distribution Tianwen-1 Mars Ion and Neutral Particle Analyzer(MINPA)
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Comparison of tragal perichondrium and COOK artificial material in endoscopic type 1 tympanoplasty
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作者 Gaofei Ye Mingguang Zhou +1 位作者 wenya li Xiuwen Jiang 《Laparoscopic, Endoscopic and Robotic Surgery》 2023年第2期63-68,共6页
Objective:Various materials have been used for tympanic membrane reconstruction in middle ear surgery.This study aimed to evaluate the difference between the tragal perichondrium and COOK arti-ficial material in patie... Objective:Various materials have been used for tympanic membrane reconstruction in middle ear surgery.This study aimed to evaluate the difference between the tragal perichondrium and COOK arti-ficial material in patients who underwent endoscopic type 1 tympanoplasty.Method:This retrospective study included patients who underwent endoscopic type 1 tympanoplasty from June 2021 to June 2022 at Sir Run Run Shaw Hospital,Zhejiang University School of Medicine.Patients were divided into group A(tragal perichondrium)and group B(COOK artificial material)ac-cording to the material used in the operation.All patients were followed up for 6 months.The differences in age,gender,operation site,disease course,preoperative air-bone gap(ABG),operation time,blood loss,hearing gain,and wound healing rate were compared between the two groups.Results:This study enrolled 197 patients,with 120 patients in group A and 77 patients in group B.There were no significant differences in age,gender,operation site,disease course,or preoperative ABG be-tween groups A and B(p>0.05).Both groups had significant postoperative improvement in hearing(group A:30.98±9.58 dB vs.17.07±9.92 dB,p<0.001;group B:29.75±7.52 dB vs.14.25±9.07 dB,p<0.001).The mean hearing gain in group A and group B was comparable(14.02±11.91 dB vs.15.50±7.05 dB,p=0.609).The wound healing rates of groups A and B were no differences(93.33%vs.87.01%,p=0.133).The patients in group B had a shorter operation duration(72.57±11.32 min vs.61.86±9.27 min,p=0.045)and less blood loss(12.38±3.7 mL vs.8.10±2.43 mL,p=0.004).Conclusions:Tragal perichondrium and COOK artificial material are reliable for functional and anatomical outcomes in endoscopic type 1 tympanoplasty,and COOK artificial material can save operation time and blood loss in surgery compared to the tragal perichondrium. 展开更多
关键词 TYMPANOPLASTY Artificial material Tragal perichondium CARTILAGE
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Chemical Constituents from Ethnic Medicine Laportea bulbifera
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作者 Ao XIE Yongjing SU +4 位作者 wenya li Junmiao MO Wenwen liANG Haicheng WEN Chen liN 《Agricultural Biotechnology》 CAS 2023年第1期47-48,52,共3页
[Objectives]This study was conducted to study the chemical constituents from Laportea bulbifera. [Methods] The 60% ethanol extract from L. bulbifera was isolated and purified by silica, Sephadex LH-20, ODS, semi-prepa... [Objectives]This study was conducted to study the chemical constituents from Laportea bulbifera. [Methods] The 60% ethanol extract from L. bulbifera was isolated and purified by silica, Sephadex LH-20, ODS, semi-preparative HPLC and recrystallization. Their chemical structures were elucidated by physicochemical properties and spectroscopic methods. [Results] These compounds were determined as kaempferol-3-O-α-L-(3-O-acetyl)-rhamnoside-7-O-α-L-rhamnoside(1), sutchuenoside A(2), kaempferol-3-O-[β-D-glucopyranosyl-(1→3)]-α-L-(4-O-acetyl)-rhamnopyranoside-7-O-α-L-rhamnopyranoside(3). Compounds 1-3 are isolated from genus Laportea for the first time. Compound 3 is a new compound. [Conclusions] This study lays a foundation for improving the quality standard of L. bulbifera and the development and utilization of its resources. 展开更多
关键词 Ethnic medicine Laportea bulbifera Chemical constituents Structural identification
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Strengthening mechanism and forming control of linear friction welded GH4169 alloy joints
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作者 Yu SU Xiawei YANG +4 位作者 Tingxi MENG Xinyuan HE Dong WU wenya li Shuo YIN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第4期609-626,共18页
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 determi... 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 elongation.When 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. 展开更多
关键词 Linear Friction Welding(LFW) Microstructure Mechanical properties Numerical simulation Joint shortening amount
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Multi-scale analyses of phase transformation mechanisms and hardness in linear friction welded Ti17(a+β)/Ti17(β)dissimilar titanium alloy joint
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作者 Zhenguo GUO Tiejun MA +3 位作者 Xiawei YANG Ju li wenya li Achilles VAIRIS 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第1期312-324,共13页
The Ti17(a+β)-Ti17(β)dual alloy-dual property blisk produced using Linear Friction Welding(LFW)is considered as high-performance component in advanced aeroengine.However,up to now,microstructure evolution and relati... The Ti17(a+β)-Ti17(β)dual alloy-dual property blisk produced using Linear Friction Welding(LFW)is considered as high-performance component in advanced aeroengine.However,up to now,microstructure evolution and relationship between microstructure and micro mechanical properties of LFWed Ti17(a+β)/Ti17(β)dissimilar joint have not been thoroughly revealed.In this work,complex analyses of the phase transformation mechanisms of the joint are conducted,and phase transformations in individual zones are correlated to their microhardness and nanohardness.Results reveal that a dissolution occurs under high temperatures encountered during LFW,which reduces microhardness of the joint to that of Ti17(a+β)and Ti17(β).In ThermoMechanically Affected Zone of Ti17(a+β)(TMAZ-(a+β))side joint,a large number of nanocrystalline a phases form with different orientations.This microstructure strengthens significantly by fine grains which balances partial softening effect of a dissolution,and increases nanohardness of a phase and microhardness of TMAZ-(a+β).Superlattice metastableβphase precipitates from metastableβin Weld Zone(WZ)during quick cooling following welding,because of short-range diffusion migration of solute atoms,especiallyβstabilizing elements Mo and Cr.The precipitation of the superlattice metastableβphase results in precipitation strengthening,which in turn increases nanohardness of metastableβand microhardness in WZ. 展开更多
关键词 Linear friction welding Ti17 titanium alloy Phase transformation MICROHARDNESS Nanohardness
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Tianwen-1 MINPA observations in the solar wind 被引量:5
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作者 AiBing Zhang lingGao Kong +25 位作者 wenya li Lei li BinBin Tang ZhaoJin Rong Yong Wei JiJie Ma YiTeng Zhang liangHai Xie YuXian Wang JianSen He Bin liu WenJing Wang Bin Su JiaWei li Xu Tan Fang Wang TaiFeng Jin FuHao Qiao Peter Wurz Yan Zhu YunFei Bai YiRen li XinBo Zhu YueQiang Sun Yongliao Zou Chi Wang 《Earth and Planetary Physics》 CSCD 2022年第1期1-9,共9页
The Mars Ion and Neutral Particle Analyzer(MINPA)is one of the three scientific instruments onboard the Tianwen-1 orbiter to investigate the Martian space environment.During Tianwen-1’s transfer orbit to Mars,the MIN... The Mars Ion and Neutral Particle Analyzer(MINPA)is one of the three scientific instruments onboard the Tianwen-1 orbiter to investigate the Martian space environment.During Tianwen-1’s transfer orbit to Mars,the MINPA was switched on to measure the solar wind ions.Here,we present the first results of the MINPA observations in the solar wind.During cruise,nearly half of the MINPA ion field-of-view(FOV)was blocked by the lander capsule;thus only the solar-wind ions with azimuthal speeds pointing towards the unblocked FOV sectors could be detected.We perform a detailed comparison of the MINPA’s solar wind observations with data from Earth-based missions when MINPA reached its count-rate peak,finding a general consistency of the ion moments between them.The blocking effect due to the lander is evaluated quantitatively under varying solar-wind velocity conditions.Despite the blocking effect,the MINPA’s solar wind measurements during the transfer orbit suggest a good performance. 展开更多
关键词 MINPA Tianwen-1 solar wind capsule blocking effect
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Statistical properties of kinetic-scale magnetic holes in terrestrial space 被引量:2
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作者 ShuTao Yao ZongShun Yue +15 位作者 QuanQi Shi Alexander William Degeling HuiShan Fu AnMin Tian Hui Zhang Andrew Vu RuiLong Guo ZhongHua Yao Ji liu Qiu-Gang Zong XuZhi Zhou JingHuan li wenya li HongQiao Hu YangYang liu WeiJie Sun 《Earth and Planetary Physics》 CSCD 2021年第1期63-72,共10页
Kinetic-scale magnetic holes(KSMHs)are structures characterized by a significant magnetic depression with a length scale on the order of the proton gyroradius.These structures have been investigated in recent studies ... Kinetic-scale magnetic holes(KSMHs)are structures characterized by a significant magnetic depression with a length scale on the order of the proton gyroradius.These structures have been investigated in recent studies in near-Earth space,and found to be closely related to energy conversion and particle acceleration,wave-particle interactions,magnetic reconnection,and turbulence at the kineticscale.However,there are still several major issues of the KSMHs that need further study—including(a)the source of these structures(locally generated in near-Earth space,or carried by the solar wind),(b)the environmental conditions leading to their generation,and(c)their spatio-temporal characteristics.In this study,KSMHs in near-Earth space are investigated statistically using data from the Magnetospheric Multiscale mission.Approximately 200,000 events were observed from September 2015 to March 2020.Occurrence rates of such structures in the solar wind,magnetosheath,and magnetotail were obtained.We find that KSMHs occur in the magnetosheath at rates far above their occurrence in the solar wind.This indicates that most of the structures are generated locally in the magnetosheath,rather than advected with the solar wind.Moreover,KSMHs occur in the downstream region of the quasi-parallel shock at rates significantly higher than in the downstream region of the quasi-perpendicular shock,indicating a relationship with the turbulent plasma environment.Close to the magnetopause,we find that the depths of KSMHs decrease as their temporal-scale increases.We also find that the spatial-scales of the KSMHs near the subsolar magnetosheath are smaller than those in the flanks.Furthermore,their global distribution shows a significant dawn-dusk asymmetry(duskside dominating)in the magnetotail. 展开更多
关键词 kinetic scale magnetic hole magnetic dip electron vortex turbulence
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A Summary of Studies on the Bark of a National Medicine Choerospondias axillaris 被引量:1
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作者 Wenyi WEI Yongjing SU +6 位作者 Can li Gan LUO Junmiao MO wenya li Haicheng WEN Xiaowei HE Wei WEI 《Medicinal Plant》 CAS 2021年第5期81-83,共3页
The bark of Choerospondias axillaris is not only an authentic medicine in Guangxi,but also one of the commonly used medicines of many ethnic minorities.This paper intends to study,summarize,and analyze the planting ar... The bark of Choerospondias axillaris is not only an authentic medicine in Guangxi,but also one of the commonly used medicines of many ethnic minorities.This paper intends to study,summarize,and analyze the planting area,harvesting and processing,processing technology,chemical composition,pharmacological action and the establishment and evaluation of quality standard of C.axillaris,in order to provide more reference basis for the development,research and utilization of Zhuang medicine C.axillaris and the establishment of quality standard. 展开更多
关键词 Bark of Choerospondias axillaris Ethnic medicine CHROMATOGRAPHY Chemical composition Quality standard
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Refill Friction Stir Spot Welding Al Alloy to Copper via Pure Metallurgical Joining Mechanism
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作者 Zhikang Shen Yuquan Ding +6 位作者 Wei Guo Wentao Hou Xiaochao liu Haiyan Chen Fenjun liu wenya li Adrian Gerlich 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第4期90-97,共8页
The current investigation of refill friction stir spot welding(refill FSSW)Al alloy to copper primarily involved plunging the tool into bottom copper sheet to achieve both metallurgical and mechanical interfacial bond... The current investigation of refill friction stir spot welding(refill FSSW)Al alloy to copper primarily involved plunging the tool into bottom copper sheet to achieve both metallurgical and mechanical interfacial bonding.Compared to conventional FSSW and pinless FSSW,weld strength can be significantly improved by using this method.Nevertheless,tool wear is a critical issue during refill FSSW.In this study,defect-free Al/copper dissimilar welds were successfully fabricated using refill FSSW by only plunging the tool into top Al alloy sheet.Overall,two types of continuous and ultra-thin intermetallic compounds(IMCs)layers were identified at the whole Al/copper interface.Also,strong evidence of melting and resolidification was observed in the localized region.The peak temperature obtained at the center of Al/copper interface was 591℃,and the heating rate reached up to 916℃/s during the sleeve penetration phase.A softened weld region was produced via refill FSSW process,the hardness profile exhibited a W-shaped appearance along middle thickness of top Al alloy.The weld lap shear load was insensitive to the welding condition,whose scatter was rather small.The fracture path exclusively propagated along the IMCs layer of Cu_(9)Al_(4) under the external lap shear loadings,both CuAl_(2) and Cu_(9)Al_(4) were detected on the fractured surface on the copper side.This research indicated that acceptable weld strength can be achieved via pure metallurgical joining mechanism,which has significant potential for the industrial applications. 展开更多
关键词 Refill friction stir spot welding Al alloy COPPER Interfacial microstructure Mechanical properties
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Analysis of local microstructure and strengthening mechanisms in adjustable-gap bobbin tool friction stir welds of Al-Mg
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作者 Dong Wu wenya li +3 位作者 Qiang Chu Yangfan Zou Xichang liu Yanjun Gao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第8期1589-1595,共7页
The bobbin tool friction stir welding process was used to join 6 mm thick 5A06 aluminum alloy plates.Optical microscope was used to characterize the microstructure.The electron backscatter diffraction(EBSD)identified ... The bobbin tool friction stir welding process was used to join 6 mm thick 5A06 aluminum alloy plates.Optical microscope was used to characterize the microstructure.The electron backscatter diffraction(EBSD)identified the effect of non-homogeneous microstructure on the tensile properties.It was observed that the grain size in the top of the stir zone(SZ)is smaller than that in the centre region.The lowest ratio of recrystallization and density of the geometrically-necessary dislocations(GNDs)in the SZ was found in the middle near the thermo-mechanically affected zone(TMAZ)being 22%and 1.15×10^(−13) m^(−2),respectively.The texture strength of the heat-affected zone(HAZ)is the largest,followed by that in the SZ,with the lowest being in the TMAZ.There were additional interfaces developed which contributed to the strengthening mechanism,and their effect on tensile strength was analysed.The tensile tests identified the weakest part in the joint at the interfaces,and the specific reduction value is about 93 MPa. 展开更多
关键词 friction stir welding bobbin-tool local microstructure strengthening mechanisms adjustable-gap
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Micro-Newton scale variable thrust control technique and its noise problem for drag-free satellite platforms:a review
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作者 Changyi XU wenya li +2 位作者 Xuhui liU Yong li Chao ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2023年第10期841-858,共18页
High-precision detection in fundamental space physics,such as space gravitational wave detection,high-precision earth gravity field measurement,and reference frame drag effect measurement,is the key to achieving impor... High-precision detection in fundamental space physics,such as space gravitational wave detection,high-precision earth gravity field measurement,and reference frame drag effect measurement,is the key to achieving important breakthroughs in the scientific study of fundamental space physics.Acquiring high-precision measurements requires high-performance satellite platforms to achieve“drag-free control”in a near“pure gravity”flight environment.The critical technology for drag-free control is variable thrust control at the micro-Newton scale.Thrust noise is the most important technical indicator for achieving drag-free flight.However,there is no literature about the current status and future prospects of variable thrust control based on thrust noise.Therefore,the micro-Newton variable thrust control technology and the thrust noise of the drag-free satellite platform are reviewed in this work.Firstly,the research status of micro-Newton scale variable thrust control technology and its applications to drag-free satellite platforms are introduced.Then,the noise problem is analyzed in detail and its solution is theoretically investigated in three aspects:“cross-basin flow problem,”“control problem,”and“system instability and multiple-coupled problem.”Finally,a systematic overview is presented and the corresponding suggested directions of research are discussed.This work provides detailed understanding and support for realizing low-noise variable thrust control in the next generation of drag-free satellites. 展开更多
关键词 Space physics detection Satellite platforms Drag-free control Micro-Newton scale variable thrust Thrust noise
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Ductile and high strength Cu fabricated by solid-state cold spray additive manufacturing
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作者 Chaoyue Chen Yingchun Xie +9 位作者 Shuo Yin wenya li Xiaotao Luo Xinliang Xie Ruixin Zhao Chunming Deng Jiang Wang Hanlin liao Min liu Zhongming Ren 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第3期234-243,共10页
In this work,pure Cu with excellent strength and ductility(UTS of 271 MPa,elongation to fracture of 43.5%,uniform elongation of 30%)was prepared using cold spray additive manufacturing(CSAM),realizing a breakthrough i... In this work,pure Cu with excellent strength and ductility(UTS of 271 MPa,elongation to fracture of 43.5%,uniform elongation of 30%)was prepared using cold spray additive manufacturing(CSAM),realizing a breakthrough in the field.An in-depth investigation was conducted to reveal the microstructure evolution,strengthening and ductilization mechanisms of the CSAM Cu,as well as the single splats.The results show that the CSAM Cu possesses a unique heterogeneous microstructure with a bimodal grain structure and extensive infinitely circulating ring-mounted distribution of twinning.Based on the single splat observation,the entire copper particle forms a gradient nano-grained(GNG)structure after high-speed impact deposition.The GNG-structured single splat serves as a unit to build the heterogeneous microstructure with bimodal grain distribution during the successive deposition in CSAM.The results also show that CSAM can achieve synergistic strengthening and ductilization by controlling the grain refinement and dislocation density.This work provides potential for CSAM technique in manufacturing various metallic parts with the desired combination of high strength and good ductility without additional post-treatments. 展开更多
关键词 Cold spray additive manufacturing Copper Heterogeneous microstructure Strength DUCTILITY
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A review of linear friction welding of Ni -based superalloys
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作者 Xiawei Yang Tingxi Meng +6 位作者 Qiang Chu Yu Su Zhenguo Guo Rui Xu Wenlong Fan Tiejun Ma wenya li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2024年第6期1382-1391,共10页
Ni-based superalloys are one of the most important materials employed in high-temperature applications within the aerospace and nuclear energy industries and in gas turbines due to their excellent corrosion,radiation,... Ni-based superalloys are one of the most important materials employed in high-temperature applications within the aerospace and nuclear energy industries and in gas turbines due to their excellent corrosion,radiation,fatigue resistance,and high-temperature strength.Linear friction welding(LFW)is a new joining technology with near-net-forming characteristics that can be used for the manu-facture and repair of a wide range of aerospace components.This paper reviews published works on LFW of Ni-based superalloys with the aim of understanding the characteristics of frictional heat generation and extrusion deformation,microstructures,mechanical proper-ties,flash morphology,residual stresses,creep,and fatigue of Ni-based superalloy weldments produced with LFW to enable future optim-um utilization of the LFW process. 展开更多
关键词 Ni-based superalloys linear friction welding microstructures mechanical properties flash morphology
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Towards high-strength cold spray additive manufactured metals:Methods,mechanisms,and properties
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作者 Shuo Yin Ningsong Fan +4 位作者 Chunjie Huang Yingchun Xie Chao Zhang Rocco Lupoi wenya li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第3期47-64,共18页
Cold spray,as a solid-state additive manufacturing process,has been attracting increasing attention from both scientific and industrial communities.However,cold-sprayed deposits generally have unfavorable mechanical p... Cold spray,as a solid-state additive manufacturing process,has been attracting increasing attention from both scientific and industrial communities.However,cold-sprayed deposits generally have unfavorable mechanical properties in their as-fabricated state compared to conventionally manufactured and fusion-based additive-manufactured counterparts due to the inherent microstructural defects in the deposits(e.g.,porosity and incomplete interparticle bonding).This downside reduces its competitiveness and limits its wide applications as an additive manufacturing process.In the past years,many strengthening technologies have been developed or introduced to adjust the microstructure and improve the mechanical properties of cold-sprayed deposits.The term“strengthening”in this work specifically refers to improving the mechanical strength,particularly the tensile strength of the cold-sprayed bulk deposits.According to the stage that the strengthening technologies are used in the cold spray process,they can be classified into three categories:pre-process(e.g.,powder heat treatment),in-process(e.g.,powder heating,in-situ micro-forging,laser-assisted cold spray),and post-process(e.g.,post heat treatment,hot isostatic pressing,hot rolling,friction stir processing).Therefore,a comprehensive review of these strengthening technolo-gies is conducted to illuminate the possible correlations between the strengthening mechanisms and the resultant deposit microstructures and mechanical properties.This review paper aims to help researchers and engineers well understand the different strengthening methods and provide guidance for the cold spray community to develop new strengthening strategies for future high-quality mass production. 展开更多
关键词 Cold spray Additive manufacturing Strengthening Microstructure DUCTILITY Tensile strength
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Solid-state additive manufacturing and repairing by cold spraying:A review 被引量:36
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作者 wenya li Kang Yang +3 位作者 Shuo Yin Xiawei Yang Yaxin Xu Rocco Lupoi 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第3期440-457,共18页
High-performance metal additive manufacturing(AM) has been extensively investigated in recent year because of its unique advantages over traditional manufacturing processes. AM has been applied to form complex compone... High-performance metal additive manufacturing(AM) has been extensively investigated in recent year because of its unique advantages over traditional manufacturing processes. AM has been applied to form complex components of Ti, Fe or Ni alloys. However, for other nonferrous alloys such as Al alloys, Mg alloys and Cu alloys, AM may not be appropriate because of its melting nature during processing by laser electron beam, and/or arc. Cold spraying(CS) has been widely accepted as a promising solid-state coating technique in last decade for its mass production of high-quality metals and alloys, and/or metal matrix composites coatings. It is now recognized as a useful and powerful tool for AM, but the related research work has just started. This review summarized the literature on the state-of-the-art and problems for C as an AM and repairing technique. 展开更多
关键词 金属添加剂 生产过程 修理技术 评论 喷洒 固态 涂层技术 合金
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Al matrix composites fabricated by solid-state cold spray deposition:A critical review 被引量:8
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作者 Xinliang Xie Shuo Yin +6 位作者 Rija-nirina Raoelison Chaoyue Chen Christophe Verdy wenya li Gang ji Zhongming Ren Hanlin liao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第27期20-55,共36页
Cold spraying(CS),or cold gas dynamic spray(CGDS),is an emerging solid-state powder deposition process,allowing fast and mass production and restoration of metallic components.CS of metal matrix composites(MMCs)has at... Cold spraying(CS),or cold gas dynamic spray(CGDS),is an emerging solid-state powder deposition process,allowing fast and mass production and restoration of metallic components.CS of metal matrix composites(MMCs)has attracted increasing attention from academia and industry over the last decades,especially in the area of Al matrix composites(AMCs),which have demonstrated a high potential for applications in aerospace,automotive,and electronics industries.This article aims to summarize the recent development of CS-processed AMCs in terms of composite powder preparation,deposition processing,microstructure evolution,mechanical and corrosion properties.Furthermore,this review also reports the relevant research progress with the focus on post-treatments of the AMCs for CS additive manufacturing applications including heat treatment,hot rolling,and friction stir processing.Finally,the challenges and perspectives on the fabrication of advanced AMCs by CS are addressed. 展开更多
关键词 Al matrix composites Solid-state cold spraying Additive manufacturing Post-treatments
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