Pub Date : 2023-07-02DOI: 10.1080/02670836.2023.2228106
Xingang Zhang, Chao Chen
The increasing availability of high-performance materials has boosted the demand for advanced joining techniques for heterogeneous sheets in the industry. The novel stepped clinching process (SCP) may become a new option for joining sheets due to the superiority in joint strength and geometric parameters compared to conventional clinching technology. The SCP for joining AA5052-H32 and Polyoxymethylene is explored experimentally in the paper. The failure mechanism of stepped clinched joints is studied at both macroscopic and microscopic levels. Increasing the forming force assists in increasing mechanical strength and improving cross-sectional geometry. The optimal energy absorption values and shear strength of 5.038 J and 2040 N were obtained in the experiments when the forming force was 32 kN.
{"title":"Experimental research on joining AA5052-H32/Polyoxymethylene sheets with novel stepped clinching process","authors":"Xingang Zhang, Chao Chen","doi":"10.1080/02670836.2023.2228106","DOIUrl":"https://doi.org/10.1080/02670836.2023.2228106","url":null,"abstract":"The increasing availability of high-performance materials has boosted the demand for advanced joining techniques for heterogeneous sheets in the industry. The novel stepped clinching process (SCP) may become a new option for joining sheets due to the superiority in joint strength and geometric parameters compared to conventional clinching technology. The SCP for joining AA5052-H32 and Polyoxymethylene is explored experimentally in the paper. The failure mechanism of stepped clinched joints is studied at both macroscopic and microscopic levels. Increasing the forming force assists in increasing mechanical strength and improving cross-sectional geometry. The optimal energy absorption values and shear strength of 5.038 J and 2040 N were obtained in the experiments when the forming force was 32 kN.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"57 1","pages":"2874 - 2884"},"PeriodicalIF":1.8,"publicationDate":"2023-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80773409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Phase transformation, microstructure evolution, and mechanical properties of Ti–3Al–5Mo–4Cr–2Zr–1Fe alloy were investigated during a continuous heating process. Three microstructures, specifically lath, duplex, and lamellar structures, were examined. The activation energies for phase transition in these structures were measured as 277, 220, and 193 kJ mol−1, respectively. The phase transition follows: For the lath structure, β transforms into αacicular (550–660°C), αacicular converts to β (660–785°C), αlath does to β (660–850°C); For the duplex structure, β transforms into αacicular (545–660°C), αacicular converts to β (660–770°C), αlath does to β (660–850°C); For the lamellar structure, β transforms into αsecondary (560–615°C), αsecondary converts to β (615–705°C), αlamellar dose to β (615–850°C). The lath and duplex structures exhibited favorable comprehensive properties compared to lamellar microstructure.
{"title":"Effect of initial microstructure on phase transformation and mechanical properties of Ti–3Al–5Mo–4Cr–2Zr–1Fe alloy","authors":"Qisong Zhu, B. Lu, Jia Xue, Feng Li, Liang Feng, Hui Chang","doi":"10.1080/02670836.2023.2230003","DOIUrl":"https://doi.org/10.1080/02670836.2023.2230003","url":null,"abstract":"Phase transformation, microstructure evolution, and mechanical properties of Ti–3Al–5Mo–4Cr–2Zr–1Fe alloy were investigated during a continuous heating process. Three microstructures, specifically lath, duplex, and lamellar structures, were examined. The activation energies for phase transition in these structures were measured as 277, 220, and 193 kJ mol−1, respectively. The phase transition follows: For the lath structure, β transforms into αacicular (550–660°C), αacicular converts to β (660–785°C), αlath does to β (660–850°C); For the duplex structure, β transforms into αacicular (545–660°C), αacicular converts to β (660–770°C), αlath does to β (660–850°C); For the lamellar structure, β transforms into αsecondary (560–615°C), αsecondary converts to β (615–705°C), αlamellar dose to β (615–850°C). The lath and duplex structures exhibited favorable comprehensive properties compared to lamellar microstructure.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"19 1","pages":"2921 - 2937"},"PeriodicalIF":1.8,"publicationDate":"2023-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85044479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-30DOI: 10.1080/02670836.2023.2229175
B. Fernández Silva, Oliver Levano Blanch, Kam Sagoo, M. Jackson
Titanium alloys are a key part of an armour designer’s toolset due to their high ballistic mass efficiency. However, titanium’s high cost has restricted its use in military land-based vehicles. In this study, the effect of different processing routes on the microstructure, texture, ballistic performance V50 and deformation modes of Ti-6Al-4V armour plate is investigated. Plates were fabricated via conventional hot rolling and the powder metallurgy techniques of HIP and FAST. The plate failure modes varied significantly with the microstructure while the formation of adiabatic shear bands seems to be influenced by crystallographic texture. The rolled plate exhibited the best performance due to a strong transverse-type texture perpendicular to the projectile direction.
{"title":"Effect of processing route on ballistic performance of Ti-6Al-4V armour plate","authors":"B. Fernández Silva, Oliver Levano Blanch, Kam Sagoo, M. Jackson","doi":"10.1080/02670836.2023.2229175","DOIUrl":"https://doi.org/10.1080/02670836.2023.2229175","url":null,"abstract":"Titanium alloys are a key part of an armour designer’s toolset due to their high ballistic mass efficiency. However, titanium’s high cost has restricted its use in military land-based vehicles. In this study, the effect of different processing routes on the microstructure, texture, ballistic performance V50 and deformation modes of Ti-6Al-4V armour plate is investigated. Plates were fabricated via conventional hot rolling and the powder metallurgy techniques of HIP and FAST. The plate failure modes varied significantly with the microstructure while the formation of adiabatic shear bands seems to be influenced by crystallographic texture. The rolled plate exhibited the best performance due to a strong transverse-type texture perpendicular to the projectile direction.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"45 1","pages":"2910 - 2920"},"PeriodicalIF":1.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83946321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-30DOI: 10.1080/02670836.2023.2228105
B. Liang, Jiaoyang Sun, Jing Zhao, Z. Ding, R. Tian, Feng Yan
The pearlite formed in 100Mn13 high carbon high manganese steel after 1323 K water toughening subsequently 923 K aging treatment is studied by transmission electron microscope and high-resolution technique. The results show that the pearlite is composed of three phases, which are M3C lamellae, M7C3 lamellae, and ferrite lamellae, respectively, with the orientation relationships of ( )α∥( )M7C3, ( )α∥( )M3C, ( )M3C∥( )M7C3, [ ]M3C∥[ ]M7C3∥[ ]α. And M7C3 is formed at the phase interface between M3C and α. The growth physical model of three-phase pearlite is proposed.
{"title":"Morphology and formation of three-phase pearlite in an aged 100Mn13 steel","authors":"B. Liang, Jiaoyang Sun, Jing Zhao, Z. Ding, R. Tian, Feng Yan","doi":"10.1080/02670836.2023.2228105","DOIUrl":"https://doi.org/10.1080/02670836.2023.2228105","url":null,"abstract":"The pearlite formed in 100Mn13 high carbon high manganese steel after 1323 K water toughening subsequently 923 K aging treatment is studied by transmission electron microscope and high-resolution technique. The results show that the pearlite is composed of three phases, which are M3C lamellae, M7C3 lamellae, and ferrite lamellae, respectively, with the orientation relationships of ( )α∥( )M7C3, ( )α∥( )M3C, ( )M3C∥( )M7C3, [ ]M3C∥[ ]M7C3∥[ ]α. And M7C3 is formed at the phase interface between M3C and α. The growth physical model of three-phase pearlite is proposed.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"16 1","pages":"2869 - 2873"},"PeriodicalIF":1.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88447854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-30DOI: 10.1080/02670836.2023.2228103
Rui Li, Song Zhang, Yonggang Xu
Mo0.5NbHf0.5ZrTiAl, Mo0.5NbHf0.5ZrTiSi0.5Al and Mo0.5NbHf0.5CrZrTiAl (molar ratio) refractory high entropy alloys (RHEA) were prepared by vacuum arc melting. The influences of Si and Cr on microstructure and properties of RHEA were investigated. Three RHEA all contain BCC1 phase. Si addition promotes the formation of M5Si3 intermetallic compound, and the microstructure of Si0.5Cr0 RHEA consists of M5Si3 blocks and BCC1 + M5Si3 eutectics. Cr addition leads to the formation of Cr2Nb type Laves phase, and two BCC dendrites exist in Si0Cr RHEA. The compressive strength of Si0.5Cr0 and Si0Cr RHEA increased by about 102% and 85%, respectively, compared to Si0Cr0 one. The oxidation resistance of RHEA is improved by adding Si while dramatically degraded by adding Cr.
{"title":"Microstructure and properties of refractory high entropy alloys containing Si and Cr","authors":"Rui Li, Song Zhang, Yonggang Xu","doi":"10.1080/02670836.2023.2228103","DOIUrl":"https://doi.org/10.1080/02670836.2023.2228103","url":null,"abstract":"Mo0.5NbHf0.5ZrTiAl, Mo0.5NbHf0.5ZrTiSi0.5Al and Mo0.5NbHf0.5CrZrTiAl (molar ratio) refractory high entropy alloys (RHEA) were prepared by vacuum arc melting. The influences of Si and Cr on microstructure and properties of RHEA were investigated. Three RHEA all contain BCC1 phase. Si addition promotes the formation of M5Si3 intermetallic compound, and the microstructure of Si0.5Cr0 RHEA consists of M5Si3 blocks and BCC1 + M5Si3 eutectics. Cr addition leads to the formation of Cr2Nb type Laves phase, and two BCC dendrites exist in Si0Cr RHEA. The compressive strength of Si0.5Cr0 and Si0Cr RHEA increased by about 102% and 85%, respectively, compared to Si0Cr0 one. The oxidation resistance of RHEA is improved by adding Si while dramatically degraded by adding Cr.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"606 1","pages":"2850 - 2858"},"PeriodicalIF":1.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77477940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-30DOI: 10.1080/02670836.2023.2230004
Jinbang Song, Yu-Duo Fu, K. Song, Qianling Zhu, Xiao-Wen Peng, Y. Hua, Y. Zhou, Xiu-hua Guo, Shivrina An, Ying-Xuan Ma
The effect of interaction between Ce and P on the microstructure and properties of copper has been rarely reported. In this study, it was investigated by utilising the OM, EPMA, SEM and TEM techniques, combined with conductivity and tensile tests. The results indicated that the grain size and conductivity of as-cast copper could be significantly influenced by the interaction. More importantly, the plasticity of as-cast copper did not seriously damage by the interaction, and the elongation of as-cast 3# (Cu-0.016P-0.075Ce) was still up to 39.3%. This is due to a strong binding force of the coherent interface between CeP and copper.
{"title":"Effect of interaction between P and Ce on properties of copper","authors":"Jinbang Song, Yu-Duo Fu, K. Song, Qianling Zhu, Xiao-Wen Peng, Y. Hua, Y. Zhou, Xiu-hua Guo, Shivrina An, Ying-Xuan Ma","doi":"10.1080/02670836.2023.2230004","DOIUrl":"https://doi.org/10.1080/02670836.2023.2230004","url":null,"abstract":"The effect of interaction between Ce and P on the microstructure and properties of copper has been rarely reported. In this study, it was investigated by utilising the OM, EPMA, SEM and TEM techniques, combined with conductivity and tensile tests. The results indicated that the grain size and conductivity of as-cast copper could be significantly influenced by the interaction. More importantly, the plasticity of as-cast copper did not seriously damage by the interaction, and the elongation of as-cast 3# (Cu-0.016P-0.075Ce) was still up to 39.3%. This is due to a strong binding force of the coherent interface between CeP and copper.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"34 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81636508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Al coating of varying thicknesses in the 50 to 200 nm range was coated on AZ31 Mg alloys to improve its corrosion capabilities. The thermal evaporation method is used for coating AZ31 Mg alloys. GIXRD, SEM, AFM and XEDS studied the structure, microstructure, and chemical analysis. GIXRD studies showed an amorphous thin film on the surface. AFM showed that the surface roughness increases with the coating thickness. Corrosion studies were done by electrochemical analysis in 3.5 wt-% NaCl environment. The Al coating has improved the corrosion resistance of the AZ31 alloy to the best with the lowest corrosion rate 0.07 mmpy, with the corrosion current density and corrosion potential of 0.32 × 10−5 A/cm2 and −1.17 V, respectively. GRAPHICAL ABSTRACT
{"title":"Corrosion inhibition capabilities of aluminium thin films on AZ31 magnesium alloy","authors":"Sundeep Kumar Marndi, Pachaiappan Raman, Amirthapandian Sankarakumar, Ponpandian Nagamony, P. Thangadurai","doi":"10.1080/02670836.2023.2226487","DOIUrl":"https://doi.org/10.1080/02670836.2023.2226487","url":null,"abstract":"Al coating of varying thicknesses in the 50 to 200 nm range was coated on AZ31 Mg alloys to improve its corrosion capabilities. The thermal evaporation method is used for coating AZ31 Mg alloys. GIXRD, SEM, AFM and XEDS studied the structure, microstructure, and chemical analysis. GIXRD studies showed an amorphous thin film on the surface. AFM showed that the surface roughness increases with the coating thickness. Corrosion studies were done by electrochemical analysis in 3.5 wt-% NaCl environment. The Al coating has improved the corrosion resistance of the AZ31 alloy to the best with the lowest corrosion rate 0.07 mmpy, with the corrosion current density and corrosion potential of 0.32 × 10−5 A/cm2 and −1.17 V, respectively. GRAPHICAL ABSTRACT","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"32 2","pages":"2792 - 2810"},"PeriodicalIF":1.8,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72542836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-27DOI: 10.1080/02670836.2023.2225902
Ashish A. Desai, B. Khatri, H. Rana, Vivek Patel, V. Badheka
{"title":"Numerical and experimental investigation on AZ91 friction stir welding joints: mechanics, properties","authors":"Ashish A. Desai, B. Khatri, H. Rana, Vivek Patel, V. Badheka","doi":"10.1080/02670836.2023.2225902","DOIUrl":"https://doi.org/10.1080/02670836.2023.2225902","url":null,"abstract":"","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81899385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-27DOI: 10.1080/02670836.2023.2228097
Zhenyu Dou, Jing Yin, Jingzhe Niu, Ming Wei, J. Wang
An equimolar AlCoCrFeNi high-entropy alloy (HEA) with trade-off properties between strength and ductility is prepared by hot extrusion for the first time. Compared with the HEAs prepared by casting and heat treatments, hot-extruded AlCoCrFeNi HEA not only contains uniform elements and phase distributions but also finer grains and microstructures. The average diameter of the homogeneous equal-axis fine grains is less than 5 µm. The compressive yield strength and ultimate compressive strength of the hot-extruded AlCoCrFeNi HEA reach 1450 and 3500 MPa respectively, while the compressive strain reach 42%. These excellent mechanical properties are attributed to the fine microstructure. In addition, the uniform dispersed network phase structures, ultrafine sub-grains, high density dislocations and blunted cracks in the deformed AlCoCrFeNi HEA are all the important factors affecting the strength and plasticity of the HEA. Hot-extruded AlCoCrFeNi HEA with excellent mechanical properties confirms a great prospect for the preparation of high-strength HEAs.
{"title":"Hot-extruded AlCoCrFeNi high-entropy alloy with ultra-high strength and large ductility","authors":"Zhenyu Dou, Jing Yin, Jingzhe Niu, Ming Wei, J. Wang","doi":"10.1080/02670836.2023.2228097","DOIUrl":"https://doi.org/10.1080/02670836.2023.2228097","url":null,"abstract":"An equimolar AlCoCrFeNi high-entropy alloy (HEA) with trade-off properties between strength and ductility is prepared by hot extrusion for the first time. Compared with the HEAs prepared by casting and heat treatments, hot-extruded AlCoCrFeNi HEA not only contains uniform elements and phase distributions but also finer grains and microstructures. The average diameter of the homogeneous equal-axis fine grains is less than 5 µm. The compressive yield strength and ultimate compressive strength of the hot-extruded AlCoCrFeNi HEA reach 1450 and 3500 MPa respectively, while the compressive strain reach 42%. These excellent mechanical properties are attributed to the fine microstructure. In addition, the uniform dispersed network phase structures, ultrafine sub-grains, high density dislocations and blunted cracks in the deformed AlCoCrFeNi HEA are all the important factors affecting the strength and plasticity of the HEA. Hot-extruded AlCoCrFeNi HEA with excellent mechanical properties confirms a great prospect for the preparation of high-strength HEAs.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"76 1","pages":"2842 - 2849"},"PeriodicalIF":1.8,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90296668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-27DOI: 10.1080/02670836.2023.2228107
Olatunji V. Oni, I. P. Oyekunle, Owolabi J. Akanni, Daniel A. Ayejoto
An alternative battery system to the lithium-ion battery has become paramount due to its high cost and limited distribution across the earth's surface. One of the significant challenges encountered by Na+ batteries is the development of efficient anode material. ZIFs have been considered as one of the potential electrode materials for Na+ batteries. ZIF is a sub-family of the metal–organic framework. Aside from the fact that they are utilised for sodium-ion batteries, their exceptional thermal stabilitiy, porous structure, and robust functionalities make them suitable for various applications. In this review, the working principles of Na+ battery, the synthesis procedure of ZIF carbon materials, electrochemical performances of each material or composite, performance enhancement strategy and morphology were explored and summarised.
{"title":"A review on ZIF carbon materials for sodium-ion battery","authors":"Olatunji V. Oni, I. P. Oyekunle, Owolabi J. Akanni, Daniel A. Ayejoto","doi":"10.1080/02670836.2023.2228107","DOIUrl":"https://doi.org/10.1080/02670836.2023.2228107","url":null,"abstract":"An alternative battery system to the lithium-ion battery has become paramount due to its high cost and limited distribution across the earth's surface. One of the significant challenges encountered by Na+ batteries is the development of efficient anode material. ZIFs have been considered as one of the potential electrode materials for Na+ batteries. ZIF is a sub-family of the metal–organic framework. Aside from the fact that they are utilised for sodium-ion batteries, their exceptional thermal stabilitiy, porous structure, and robust functionalities make them suitable for various applications. In this review, the working principles of Na+ battery, the synthesis procedure of ZIF carbon materials, electrochemical performances of each material or composite, performance enhancement strategy and morphology were explored and summarised.","PeriodicalId":18232,"journal":{"name":"Materials Science and Technology","volume":"13 1","pages":"2616 - 2632"},"PeriodicalIF":1.8,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87667747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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