Pub Date : 2023-11-06DOI: 10.24425/afe.2019.127135
Jialiu Lei, Dongnan Zhao, Yongjun Fu, Xianfeng Xu
In the present investigation, the morphology of Ti inclusions in high strength tire cord steel was investigated and their precipitation behavior was discussed using a precipitation and growth model. The results show that Ti inclusions mainly exist in the form of TiN. The two-dimensional characterization of Ti inclusions is square-like with sharp edges and corners, while its three-dimensional shape exhibits a cubic or rectangular-prism morphology. The Ti inclusions do not precipitate when the solid fraction of tire cord during solidification is less than 0.987, and their final radius is closely related to the cooling rate and initial concentration product. The higher the cooling speed, the smaller the final radius, when the cooling speed is constant, the final radius of Ti inclusions is mainly determined by the initial concentration product, w[N]0×w[Ti]0. In order to retard the precipitation and growth of Ti inclusions in tire cord steel, the cooling rate and initial concentration product can be taken into consideration.
{"title":"Research on the Characterization of Ti Inclusions and Their Precipitation Behavior in Tire Cord Steel","authors":"Jialiu Lei, Dongnan Zhao, Yongjun Fu, Xianfeng Xu","doi":"10.24425/afe.2019.127135","DOIUrl":"https://doi.org/10.24425/afe.2019.127135","url":null,"abstract":"In the present investigation, the morphology of Ti inclusions in high strength tire cord steel was investigated and their precipitation behavior was discussed using a precipitation and growth model. The results show that Ti inclusions mainly exist in the form of TiN. The two-dimensional characterization of Ti inclusions is square-like with sharp edges and corners, while its three-dimensional shape exhibits a cubic or rectangular-prism morphology. The Ti inclusions do not precipitate when the solid fraction of tire cord during solidification is less than 0.987, and their final radius is closely related to the cooling rate and initial concentration product. The higher the cooling speed, the smaller the final radius, when the cooling speed is constant, the final radius of Ti inclusions is mainly determined by the initial concentration product, w[N]0×w[Ti]0. In order to retard the precipitation and growth of Ti inclusions in tire cord steel, the cooling rate and initial concentration product can be taken into consideration.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"1988 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135635833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/afe.2020.133329
This article proposes these of vibratory machining to Ti-6Al-4V titanium alloy as finishing treatment. Titanium alloy was used in the aerospace industry, military, metallurgical, automotive and medical processes, extreme sports and other. The three-level three-factor Box-Behnken experiment examined the influence of machining time of vibratory machining, the type of mass finishing media used and the initial state of the surface layer on the mass loss, geometric structure of the surface, micro hardness and the optimal process parameters were determined. Considerations were given the surfaces after milling, after cutting with a band saw and after the sanding process. The experiment used three types of mass finishing media: polyester, porcelain and metal. Duration of vibratory machining treatment was assumed to be 20, 40, 60 minutes. The form profiles before and after vibratory machining were determined with the Talysurf CCI Lite Taylor Hobson optical profiler. Future tests should concern research to carry out tests using abrasive pastes with a larger granulation of abrasive grains, to carry out tests for longer processing times and to determine the time after which the parameters of geometrical structure of the surface change is unnoticeable.
{"title":"Research on the Influence of Vibratory Machining on Titanium Alloys Properties","authors":"","doi":"10.24425/afe.2020.133329","DOIUrl":"https://doi.org/10.24425/afe.2020.133329","url":null,"abstract":"This article proposes these of vibratory machining to Ti-6Al-4V titanium alloy as finishing treatment. Titanium alloy was used in the aerospace industry, military, metallurgical, automotive and medical processes, extreme sports and other. The three-level three-factor Box-Behnken experiment examined the influence of machining time of vibratory machining, the type of mass finishing media used and the initial state of the surface layer on the mass loss, geometric structure of the surface, micro hardness and the optimal process parameters were determined. Considerations were given the surfaces after milling, after cutting with a band saw and after the sanding process. The experiment used three types of mass finishing media: polyester, porcelain and metal. Duration of vibratory machining treatment was assumed to be 20, 40, 60 minutes. The form profiles before and after vibratory machining were determined with the Talysurf CCI Lite Taylor Hobson optical profiler. Future tests should concern research to carry out tests using abrasive pastes with a larger granulation of abrasive grains, to carry out tests for longer processing times and to determine the time after which the parameters of geometrical structure of the surface change is unnoticeable.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"667 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/afe.2020.133339
Recently, aluminum matrix syntactic foams (AMSFs) have become notably attractive for many different industrial areas like automotive, aerospace, construction and defense. Owing to their low density, good compression response and perfect energy absorption capacity, these advanced composite materials are also considered as strong alternatives to traditional particle reinforced composites and metal foams. This paper presents a promising probability of AMSF fabrication by means of industrial cold chamber die casting method. In this investigation, contrary to other literature studies restricted in laboratory scale, fully equipped custom-build cold chamber die casting machine was used first time and all fabrication steps were designed just as carried out in the real industrial high pressure casting applications. Main casting parameters (casting temperature, injection pressure, piston speed, filler pre-temperature and piston waiting time) were optimized in order to obtain flawless AMSF samples. The density alterations of the syntactic foams were analyzed depending upon increasing process values of injection pressure, piston speed and piston waiting time. In addition, macroscopic and microscopic investigations were performed to comprehend physical properties of fabricated foams. All these efforts showed almost perfect infiltration between filler particles at the optimized injection parameters
{"title":"Fabrication Optimization of Al 7075/Expanded Glass Syntactic Foam by Cold Chamber Die Casting","authors":"","doi":"10.24425/afe.2020.133339","DOIUrl":"https://doi.org/10.24425/afe.2020.133339","url":null,"abstract":"Recently, aluminum matrix syntactic foams (AMSFs) have become notably attractive for many different industrial areas like automotive, aerospace, construction and defense. Owing to their low density, good compression response and perfect energy absorption capacity, these advanced composite materials are also considered as strong alternatives to traditional particle reinforced composites and metal foams. This paper presents a promising probability of AMSF fabrication by means of industrial cold chamber die casting method. In this investigation, contrary to other literature studies restricted in laboratory scale, fully equipped custom-build cold chamber die casting machine was used first time and all fabrication steps were designed just as carried out in the real industrial high pressure casting applications. Main casting parameters (casting temperature, injection pressure, piston speed, filler pre-temperature and piston waiting time) were optimized in order to obtain flawless AMSF samples. The density alterations of the syntactic foams were analyzed depending upon increasing process values of injection pressure, piston speed and piston waiting time. In addition, macroscopic and microscopic investigations were performed to comprehend physical properties of fabricated foams. All these efforts showed almost perfect infiltration between filler particles at the optimized injection parameters","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"397 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/afe.2019.127127
The results of testing the strength properties of experimental ceramic materials containing spending moulding sand after initial mechanical reclamation as a material for subsequent layers of the stucco composition were presented. Tests were carried out on spent moulding sands from various foundry technologies, i.e. sand with furfuryl resin and sand with hydrated sodium silicate. The spent, agglomerated moulding sand has undergone a crushing process. Next, the required granular fractions used for individual layers of the stucco material were separated. Ceramic samples, in which the spent moulding sand was a substitute for fresh silica sand in successive layers of the stucco composition, were prepared. As a reference material, identical ceramic samples were used but with all layers made from the fresh silica sand. Samples prepared in this way were used to determine the bending strength of ceramic materials in the temperature range from 20 to 900ºC. The obtained values of the bending strength have demonstrated that spent moulding sand can be used in investment casting with no adverse effect on the strength of ceramic materials.
{"title":"Strength Properties of Ceramic Moulds Containing Spent Moulding Sand After Initial Reclamation","authors":"","doi":"10.24425/afe.2019.127127","DOIUrl":"https://doi.org/10.24425/afe.2019.127127","url":null,"abstract":"The results of testing the strength properties of experimental ceramic materials containing spending moulding sand after initial mechanical reclamation as a material for subsequent layers of the stucco composition were presented. Tests were carried out on spent moulding sands from various foundry technologies, i.e. sand with furfuryl resin and sand with hydrated sodium silicate. The spent, agglomerated moulding sand has undergone a crushing process. Next, the required granular fractions used for individual layers of the stucco material were separated. Ceramic samples, in which the spent moulding sand was a substitute for fresh silica sand in successive layers of the stucco composition, were prepared. As a reference material, identical ceramic samples were used but with all layers made from the fresh silica sand. Samples prepared in this way were used to determine the bending strength of ceramic materials in the temperature range from 20 to 900ºC. The obtained values of the bending strength have demonstrated that spent moulding sand can be used in investment casting with no adverse effect on the strength of ceramic materials.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"674 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/afe.2020.133327
The study presented in this paper concerned the possibility to apply a heat treatment process to ductile cast-iron thin-walled castings in order to remove excessive quantities of pearlite and eutectic cementite precipitates and thus meet the customer’s requirements. After determining the rates of heating a casting up to and cooling down from 900°C feasible in the used production heat treatment furnace ( v h = 300°C/h and v c = 200°C/h, respectively), dilatometric tests were carried out to evaluate temperatures T gr , T Ac 1start , T Ac 1end , T Ar 1start and T Ar 1end . The newly acquired knowledge was the base on which conditions for a single-step ferritizing heat treatment securing disintegration of pearlite were developed as well as those of a two-step ferritization process guaranteeing complete disintegration of cementite and arriving at the required ferrite and pearlite content. A purely ferritic matrix and hardness of 119 HB was secured by the treatment scheme: 920°C for 2 hours / v c = 60°C/h / 720°C for 4 hours. A matrix containing 20–45% of pearlite and hardness of 180–182 HB was obtained by applying: 920°C for 2 hours or 4 hours / v c = 200°C/h to 650°C / ambient air.
{"title":"Ductile Cast Iron Microstructure Adjustment by Means of Heat Treatment","authors":"","doi":"10.24425/afe.2020.133327","DOIUrl":"https://doi.org/10.24425/afe.2020.133327","url":null,"abstract":"The study presented in this paper concerned the possibility to apply a heat treatment process to ductile cast-iron thin-walled castings in order to remove excessive quantities of pearlite and eutectic cementite precipitates and thus meet the customer’s requirements. After determining the rates of heating a casting up to and cooling down from 900°C feasible in the used production heat treatment furnace ( v h = 300°C/h and v c = 200°C/h, respectively), dilatometric tests were carried out to evaluate temperatures T gr , T Ac 1start , T Ac 1end , T Ar 1start and T Ar 1end . The newly acquired knowledge was the base on which conditions for a single-step ferritizing heat treatment securing disintegration of pearlite were developed as well as those of a two-step ferritization process guaranteeing complete disintegration of cementite and arriving at the required ferrite and pearlite content. A purely ferritic matrix and hardness of 119 HB was secured by the treatment scheme: 920°C for 2 hours / v c = 60°C/h / 720°C for 4 hours. A matrix containing 20–45% of pearlite and hardness of 180–182 HB was obtained by applying: 920°C for 2 hours or 4 hours / v c = 200°C/h to 650°C / ambient air.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"491 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135637100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/afe.2020.133351
The series of experiments was performed on commercial polymeric composite material MultimetalStahl 1018. Strength tests were performed to determine the yield point of the material. The composite had the highest hardness at a temperature of 20°C. Hardness and microhardness were determined in further experiments. The adhesiveness of the material to metal surfaces and impact strength were also analyzed. The scanning electron microscopy and X-ray microanalysis methods were used for analyzing the microstructure of the material. Chemical composition of selected areas was analyzed, which allowed for a preliminary identification of metallic elements content in the composite. The microstructure of composite is highly non-homogeneous and particular phases are highly elongated and angular. The analyzed phase was enriched with silicon, aluminium, magnesium, iron and vanadium other phases enriched with metallic elements, e
{"title":"Multimetal Stahl 1018 Composite – Structure and Strength Properties","authors":"","doi":"10.24425/afe.2020.133351","DOIUrl":"https://doi.org/10.24425/afe.2020.133351","url":null,"abstract":"The series of experiments was performed on commercial polymeric composite material MultimetalStahl 1018. Strength tests were performed to determine the yield point of the material. The composite had the highest hardness at a temperature of 20°C. Hardness and microhardness were determined in further experiments. The adhesiveness of the material to metal surfaces and impact strength were also analyzed. The scanning electron microscopy and X-ray microanalysis methods were used for analyzing the microstructure of the material. Chemical composition of selected areas was analyzed, which allowed for a preliminary identification of metallic elements content in the composite. The microstructure of composite is highly non-homogeneous and particular phases are highly elongated and angular. The analyzed phase was enriched with silicon, aluminium, magnesium, iron and vanadium other phases enriched with metallic elements, e","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"496 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135637408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/AFE.2020.133324
J. Lelito
The paper presents research of metallic glass based on a Mg72Zn24Ca4 alloy. Metallic glass was prepared using induction melting and further injection on a spinning copper wheel. The X-ray diffractometer and differential scanning calorimeter (DSC) were used to investigate the phase transformation of the amorphous ribbon. The heat released in the crystallization process, during isothermal annealing, based on the differential scanning calorimeter investigation, was determined to be 166.18 Jg -1 . The effect of isothermal annealing temperature on the kinetics of the amorphous alloy crystallization process using differential scanning calorimeter was investigated. For this purpose, two isothermal annealing temperatures were selected. The incubation time decreases as the temperature of the isothermal annealing increases from 300 to 252 seconds. The same relationship is visible in the case of duration of the phase transformation, which also decreases as the temperature of the isothermal annealing increases from 360 to 228 seconds. The obtained results show a significant influence of isothermal annealing temperature on the degree of phase transformation.
{"title":"Phase Transformation Analysis of the Amorphous Mg72Zn24Ca4 Alloy","authors":"J. Lelito","doi":"10.24425/AFE.2020.133324","DOIUrl":"https://doi.org/10.24425/AFE.2020.133324","url":null,"abstract":"The paper presents research of metallic glass based on a Mg72Zn24Ca4 alloy. Metallic glass was prepared using induction melting and further injection on a spinning copper wheel. The X-ray diffractometer and differential scanning calorimeter (DSC) were used to investigate the phase transformation of the amorphous ribbon. The heat released in the crystallization process, during isothermal annealing, based on the differential scanning calorimeter investigation, was determined to be 166.18 Jg -1 . The effect of isothermal annealing temperature on the kinetics of the amorphous alloy crystallization process using differential scanning calorimeter was investigated. For this purpose, two isothermal annealing temperatures were selected. The incubation time decreases as the temperature of the isothermal annealing increases from 300 to 252 seconds. The same relationship is visible in the case of duration of the phase transformation, which also decreases as the temperature of the isothermal annealing increases from 360 to 228 seconds. The obtained results show a significant influence of isothermal annealing temperature on the degree of phase transformation.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68944448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/AFE.2019.127108
M. Boháčik, M. Mičian, R. Koňar, L. Trško, J. Winczek
The goal of this article is non-destructive ultrasonic testing of internal castings defects. Our task was to cast several samples with defects like porosity and cavities (where belongs mostly shrinkages) and then pass these samples under ultrasonic testing. The characteristics of ultrasonic control of castings are presented in the theoretical part of this article. Ultrasonic control is a volume non-destructive method that can detect internal defects in controlled materials without damaging the construction. It is one of the most widely used methods of volume non-destructive testing. For experimental control were made several cylindrical samples from ferritic grey and ductile cast iron. Because of the form and dispersion of graphite of grey cast iron it was not possible to make ultrasonic records on this casting with probe we used, so we worked only with ductile cast iron. Ultrasonic records of casting control are shown and described in the experimental part. The evaluation of the measurement results and the reliability of the ultrasonic method in castings control is listed at the end of this article.
{"title":"Ultrasonic Control of Ductile Cast Iron Castings by Phased Array Technique","authors":"M. Boháčik, M. Mičian, R. Koňar, L. Trško, J. Winczek","doi":"10.24425/AFE.2019.127108","DOIUrl":"https://doi.org/10.24425/AFE.2019.127108","url":null,"abstract":"The goal of this article is non-destructive ultrasonic testing of internal castings defects. Our task was to cast several samples with defects like porosity and cavities (where belongs mostly shrinkages) and then pass these samples under ultrasonic testing. The characteristics of ultrasonic control of castings are presented in the theoretical part of this article. Ultrasonic control is a volume non-destructive method that can detect internal defects in controlled materials without damaging the construction. It is one of the most widely used methods of volume non-destructive testing. For experimental control were made several cylindrical samples from ferritic grey and ductile cast iron. Because of the form and dispersion of graphite of grey cast iron it was not possible to make ultrasonic records on this casting with probe we used, so we worked only with ductile cast iron. Ultrasonic records of casting control are shown and described in the experimental part. The evaluation of the measurement results and the reliability of the ultrasonic method in castings control is listed at the end of this article.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68944592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/afe.2019.127138
B. Piekarski, A. Drotlew
Examples of cast grates whose construction was based on previously used "old" patterns of the technological equipment for heat treatment furnaces (TEq) are presented. Manufacturers of this type of castings have at their disposal numerous earlier designs of the applied TEq. Their adaptation for the needs of a new order, i.e. the creation of a new design or modification of the already existing one, significantly reduces both cost and time of the implementation. It also allows making new grate constructions of various shapes and sizes, reducing in this way the number of patterns stored by the manufacturer of castings. The examples of cast grates shown and discussed in this study document the variety of ways that can be used when making them from the already existing patterns or castings. The presented grates were made using master patterns, entire castings or their fragments, and modular segments.
{"title":"Cast Grates Used in Heat Treatment Furnaces","authors":"B. Piekarski, A. Drotlew","doi":"10.24425/afe.2019.127138","DOIUrl":"https://doi.org/10.24425/afe.2019.127138","url":null,"abstract":"Examples of cast grates whose construction was based on previously used \"old\" patterns of the technological equipment for heat treatment furnaces (TEq) are presented. Manufacturers of this type of castings have at their disposal numerous earlier designs of the applied TEq. Their adaptation for the needs of a new order, i.e. the creation of a new design or modification of the already existing one, significantly reduces both cost and time of the implementation. It also allows making new grate constructions of various shapes and sizes, reducing in this way the number of patterns stored by the manufacturer of castings. The examples of cast grates shown and discussed in this study document the variety of ways that can be used when making them from the already existing patterns or castings. The presented grates were made using master patterns, entire castings or their fragments, and modular segments.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":"8 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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