High temperature applications such as turbine blades for aeronautics or molten glass-shaping tools require the use of refractory metallic materials. Among the later ones, cast superalloys based on some transition metals and reinforced by MC carbides stay in good place and their metallurgy merits to be well known. This work consists in a general exploration of the as-cast microstructures which can be obtained after solidification and solid state cooling down to ambient temperature for a wide series of alloys for which the base element and the MC-former element both vary. For fixed contents in chromium and carbon contents, the compositions of a total of nineteen alloys were considered. These alloys are based on Ni, Co, Fe or Nb and the M content was each time chosen to favor the appearance of TiC, TaC, NbC, HfC or ZrC, as single carbide in a given alloy. After elaboration, metallographic samples were observed by electron microscopy to investigate the obtained microstructures. The obtained results show first that the MC carbides were in many cases successfully obtained at the expense of other possible carbides (for all Co-based alloys for example) but there are also several exceptions (notably for some Ni-based alloys). Second, the obtained monocarbides have a eutectic origin and they are script-liked shaped. However they are here too some exceptions, as the rare HfC obtained in a Nb-base). In general, the results obtained in this work show that the principle of dendritic matrix combined with MC carbides with a script-like morphology is not necessarily obtained: the nature of the {base element, MC-former element} combination governs the microstructure of the alloy in its as-cast state for these particular compositions in chromium and carbon. In some cases other carbides may appear and the microstructures may be even of another type.
{"title":"Influence of the M and M’ Metals on the Carbides Population in As-Cast M’-based Alloys Designed to be MC-Strengthened","authors":"P. Berthod","doi":"10.30564/JMMR.V2I1.604","DOIUrl":"https://doi.org/10.30564/JMMR.V2I1.604","url":null,"abstract":"High temperature applications such as turbine blades for aeronautics or molten glass-shaping tools require the use of refractory metallic materials. Among the later ones, cast superalloys based on some transition metals and reinforced by MC carbides stay in good place and their metallurgy merits to be well known. This work consists in a general exploration of the as-cast microstructures which can be obtained after solidification and solid state cooling down to ambient temperature for a wide series of alloys for which the base element and the MC-former element both vary. For fixed contents in chromium and carbon contents, the compositions of a total of nineteen alloys were considered. These alloys are based on Ni, Co, Fe or Nb and the M content was each time chosen to favor the appearance of TiC, TaC, NbC, HfC or ZrC, as single carbide in a given alloy. After elaboration, metallographic samples were observed by electron microscopy to investigate the obtained microstructures. The obtained results show first that the MC carbides were in many cases successfully obtained at the expense of other possible carbides (for all Co-based alloys for example) but there are also several exceptions (notably for some Ni-based alloys). Second, the obtained monocarbides have a eutectic origin and they are script-liked shaped. However they are here too some exceptions, as the rare HfC obtained in a Nb-base). In general, the results obtained in this work show that the principle of dendritic matrix combined with MC carbides with a script-like morphology is not necessarily obtained: the nature of the {base element, MC-former element} combination governs the microstructure of the alloy in its as-cast state for these particular compositions in chromium and carbon. In some cases other carbides may appear and the microstructures may be even of another type.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114868671","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}
In this study, the usage wastewater from secondary treatment in feeding fishes of Carassius gibelio species and suitability of the fishes for human food were evaluated. The metals (Ag, Al, As and B) in treated effluent and skeleton, skin, eyes and brain tissues of fishes were examined seasonally. It was found that treated effluent was not suitable for irrigation and aquaculture in terms of Al according to the Turkish standard values. According to annual averages the size order of Ag and B concentrations were skeleton> skin> eyes>brain and skeleton> skin>brain>eye respectively. Also, skin>brain>eyes>skeleton was for As and Al. TF (Transfer Factor) values of all metals examined were determined as >1 in the four tissues and the metals caused bioaccumulation because of treated effluent. Concentrations in muscles were found 7 to 6227 times higher than in water. The size order of TF and BCF (Bio-concentration Factor) values in skin and eye tissue were the same and it was Ag>Al>As>B. It was Ag>Al>As>B in skeleton, Al>As>Ag>B in brain. HQ (Hazard Quotient) of Al in all tissues had carcinogenic risk level.
{"title":"Health Risks of Trace Metals in Wastewater-Fed Fishes: A Case Study","authors":"A. Katip","doi":"10.30564/JMMR.V2I1.540","DOIUrl":"https://doi.org/10.30564/JMMR.V2I1.540","url":null,"abstract":"In this study, the usage wastewater from secondary treatment in feeding fishes of Carassius gibelio species and suitability of the fishes for human food were evaluated. The metals (Ag, Al, As and B) in treated effluent and skeleton, skin, eyes and brain tissues of fishes were examined seasonally. It was found that treated effluent was not suitable for irrigation and aquaculture in terms of Al according to the Turkish standard values. According to annual averages the size order of Ag and B concentrations were skeleton> skin> eyes>brain and skeleton> skin>brain>eye respectively. Also, skin>brain>eyes>skeleton was for As and Al. TF (Transfer Factor) values of all metals examined were determined as >1 in the four tissues and the metals caused bioaccumulation because of treated effluent. Concentrations in muscles were found 7 to 6227 times higher than in water. The size order of TF and BCF (Bio-concentration Factor) values in skin and eye tissue were the same and it was Ag>Al>As>B. It was Ag>Al>As>B in skeleton, Al>As>Ag>B in brain. HQ (Hazard Quotient) of Al in all tissues had carcinogenic risk level.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"381 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134075454","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}
Hot cracking susceptibility of fillers 52 and 82 in 800H and 825 nickel-base superalloys was discussed using the Spot Varestraint test. The fillers of 52 and 82 were added into nickel-base superalloys via a gas tungsten arc welding (GTAW).Experimental results showed that the hot cracking sensitivity of the nickel-base superalloys with filler at high temperature was lower than that without filler. The hot cracking sensitivity had a slight effect when the filler 82 was added. The total length of crack was increased, the liquid-solid (L-S) two-phase range is higher so that the hot cracking susceptibility will be raised. The morphologies of cracks included the intergranular crack in the molten pool, molten pool of solidification cracking, heat-affected zone of intergranular cracks, and transgranular crack in the heat-affected zone.
{"title":"Hot Cracking Susceptibility of 800H and 825 Nickel-Base Superalloys during Welding via Spot Varestraint Test","authors":"Chih-Chun Hsieh","doi":"10.30564/JMMR.V2I1.958","DOIUrl":"https://doi.org/10.30564/JMMR.V2I1.958","url":null,"abstract":"Hot cracking susceptibility of fillers 52 and 82 in 800H and 825 nickel-base superalloys was discussed using the Spot Varestraint test. The fillers of 52 and 82 were added into nickel-base superalloys via a gas tungsten arc welding (GTAW).Experimental results showed that the hot cracking sensitivity of the nickel-base superalloys with filler at high temperature was lower than that without filler. The hot cracking sensitivity had a slight effect when the filler 82 was added. The total length of crack was increased, the liquid-solid (L-S) two-phase range is higher so that the hot cracking susceptibility will be raised. The morphologies of cracks included the intergranular crack in the molten pool, molten pool of solidification cracking, heat-affected zone of intergranular cracks, and transgranular crack in the heat-affected zone.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122503180","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}
AbstractThermal barrier coating (TBC) system composing of bond coat, having two different metallic bond coating materials such as NiCoCrAlY and CoNiCrAlY, and top coat, 8YSZ (8 wt%Y2O3-ZrO2) ceramic coating was deposited on aluminum-based alloy by atmoshpheric plasma spray (APS). Fatigue test and tensile test both was performed for TBC sample. The tensile test and fatigue, both results showed that that fracture occurred in 8YSZ coating near the interface of ceramic-bond coating. These lead to the formation of weak inter-bonding strength and the failure of APS 8YSZ TBC. Moreover, in order to better understand the failure process, a deposition mechanism of coating was proposed. Experimental observations of the failed specimens subjected to tensile as well as fatigue loading showed that the coating cracking and spallation processes were different. Tensile results highlighted the different fracture mode and crack propagation up to macroscopic failure.
{"title":"Study on the tensile and the fatigue behavior of air plasma sprayed YSZ TBC systems","authors":"Dipak Kumar","doi":"10.30564/JMMR.V1I1.452","DOIUrl":"https://doi.org/10.30564/JMMR.V1I1.452","url":null,"abstract":"AbstractThermal barrier coating (TBC) system composing of bond coat, having two different metallic bond coating materials such as NiCoCrAlY and CoNiCrAlY, and top coat, 8YSZ (8 wt%Y2O3-ZrO2) ceramic coating was deposited on aluminum-based alloy by atmoshpheric plasma spray (APS). Fatigue test and tensile test both was performed for TBC sample. The tensile test and fatigue, both results showed that that fracture occurred in 8YSZ coating near the interface of ceramic-bond coating. These lead to the formation of weak inter-bonding strength and the failure of APS 8YSZ TBC. Moreover, in order to better understand the failure process, a deposition mechanism of coating was proposed. Experimental observations of the failed specimens subjected to tensile as well as fatigue loading showed that the coating cracking and spallation processes were different. Tensile results highlighted the different fracture mode and crack propagation up to macroscopic failure. ","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123039741","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}
Metal swarf is unavoidable material in metal processing industry, also metal swarf treatment lead to cost savings by metal waste reduction and removing the cutting fluid waste, that cause to increasing process stability and metal value. It is interested that in how to recycle metal swarf especially when swarf surrounded by cutting fluid, is considered because these waste are classified as hazardous waste. The aim of the study is to increase the process efficiency and environmental performance by metal waste reduction at source which are the first step of the waste hierarchy. The results of the experiments showed that 3391 tons of metal swarf coated with cutting fluids which contained 2.29% cutting fluid be produced annually. It has been found that if the total amount of cutting fluid on the swarf surface be reduced to less than 1% leads to a significant mass reduction in the amount of hazardous waste. In this research, it was considered, 107,922 USD profit at the end of first year and 205,278 USD at the end of second year would be obtained by reducing the cutting fluid content from 2.29% to 0.8% with using cutting fluid that surrounded metal swarf separation equipment in manufacturing location.
{"title":"Metal Swarf and Cutting Fluid Waste Management in Metal Processing Industry","authors":"N. K. Salihoglu, Z. Amin, Çagla Celikli","doi":"10.30564/JMMR.V1I1.431","DOIUrl":"https://doi.org/10.30564/JMMR.V1I1.431","url":null,"abstract":"Metal swarf is unavoidable material in metal processing industry, also metal swarf treatment lead to cost savings by metal waste reduction and removing the cutting fluid waste, that cause to increasing process stability and metal value. It is interested that in how to recycle metal swarf especially when swarf surrounded by cutting fluid, is considered because these waste are classified as hazardous waste. The aim of the study is to increase the process efficiency and environmental performance by metal waste reduction at source which are the first step of the waste hierarchy. The results of the experiments showed that 3391 tons of metal swarf coated with cutting fluids which contained 2.29% cutting fluid be produced annually. It has been found that if the total amount of cutting fluid on the swarf surface be reduced to less than 1% leads to a significant mass reduction in the amount of hazardous waste. In this research, it was considered, 107,922 USD profit at the end of first year and 205,278 USD at the end of second year would be obtained by reducing the cutting fluid content from 2.29% to 0.8% with using cutting fluid that surrounded metal swarf separation equipment in manufacturing location.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127669707","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}
Flocculation presents one of the most effective methods for enhancing separation of both anthropogenic and natural suspensions by sedimentation, filtration and flotation techniques.The flocculation effectiveness much depends on the medium shear rate in a flocculator. The objective of this research comprises the study how the suspension dispersity and concentration effect the efficiency of its flocculation in a static tubular flocculator and in a dynamic Couette flocculator. The studies used aqueous suspensions of ultra-fine calcium carbonate (<7 μm) and fine silica (<90 μm) as objects. It was established that treatment of ultra-fine calcium carbonate suspension in a static flocculator produced in the range 400-450 s-1 a pronounced primary maximum in the dependence "flocculation efficiency/shear rate". The increase of the suspension concentration to 70 g/l and above resulted in a small secondary maximum of the flocculation efficiency in the region of around 950 s-1. This can be due to a higher dissolution rate of flocculant and a corresponding increase of particles adhesion forces in flocs, which counteract viscous forces destroying them. In silicon dioxide suspension treatment, the primary and secondary peaks occur at both small and high suspension concentrations, but in a latter case, they are by far more pronounced and comparable in magnitude.
{"title":"Effects of suspension dispersity and concentration on its flocculation efficiency in static and dynamic flocculators","authors":"N. Rulyov, O. Kravtchenko, F. Concha","doi":"10.30564/JMMR.V1I1.411","DOIUrl":"https://doi.org/10.30564/JMMR.V1I1.411","url":null,"abstract":"Flocculation presents one of the most effective methods for enhancing separation of both anthropogenic and natural suspensions by sedimentation, filtration and flotation techniques.The flocculation effectiveness much depends on the medium shear rate in a flocculator. The objective of this research comprises the study how the suspension dispersity and concentration effect the efficiency of its flocculation in a static tubular flocculator and in a dynamic Couette flocculator. The studies used aqueous suspensions of ultra-fine calcium carbonate (<7 μm) and fine silica (<90 μm) as objects. It was established that treatment of ultra-fine calcium carbonate suspension in a static flocculator produced in the range 400-450 s-1 a pronounced primary maximum in the dependence \"flocculation efficiency/shear rate\". The increase of the suspension concentration to 70 g/l and above resulted in a small secondary maximum of the flocculation efficiency in the region of around 950 s-1. This can be due to a higher dissolution rate of flocculant and a corresponding increase of particles adhesion forces in flocs, which counteract viscous forces destroying them. In silicon dioxide suspension treatment, the primary and secondary peaks occur at both small and high suspension concentrations, but in a latter case, they are by far more pronounced and comparable in magnitude.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115255065","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}
This article is described the various possible schemes of severe plastic deformation, by ECAP process that allows receiving metal with ultrafine-grained structure. The results of computer simulation and TEM investigations of aluminium alloy 6060 were presented. It is shown that the equal-channel angular pressing in the proposed matrix with a quasi-starched channel joint angle 45° provides the formation of a homogeneous subgrain structure with a size about 0.5 µm and has a positive effect on the mechanical properties of the aluminium alloy.
{"title":"STUDY OF DEFORMATION OF ALUMINIUM ALLOY IN EQUAL CHANNEL ANGULAR MATRIX WITH QUASI-SMALL CHANNELS INTERSECTION ANGLE","authors":"S. Lezhnev","doi":"10.30564/jmmr.v1i1.312","DOIUrl":"https://doi.org/10.30564/jmmr.v1i1.312","url":null,"abstract":"This article is described the various possible schemes of severe plastic deformation, by ECAP process that allows receiving metal with ultrafine-grained structure. The results of computer simulation and TEM investigations of aluminium alloy 6060 were presented. It is shown that the equal-channel angular pressing in the proposed matrix with a quasi-starched channel joint angle 45° provides the formation of a homogeneous subgrain structure with a size about 0.5 µm and has a positive effect on the mechanical properties of the aluminium alloy.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123476779","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}
The thermal barrier coatings (TBCs) of 8wt.% yttria stabilized zirconia (8YSZ) on a GH2132 alloy were deposited by air plasma spraying. The combined effect of thermal shock and hot corrosion on the failure of TBCs was highlighted investigated. The results showed that the combined effect of hot corrosion and thermal shock was prone to induce the failure of TBCs. The main failure of TBCs under the combined effect was in the form of penetrating crack to the bondcoat/substrate interface and oxidation at the penetrating crack front.
{"title":"Combined effect of thermal shock and hot corrosion on the failure of yttria stabilized zirconia thermal barrier coatings","authors":"Changhai Zhou, X. Li, R. Pan","doi":"10.30564/JMMR.V1I1.307","DOIUrl":"https://doi.org/10.30564/JMMR.V1I1.307","url":null,"abstract":"The thermal barrier coatings (TBCs) of 8wt.% yttria stabilized zirconia (8YSZ) on a GH2132 alloy were deposited by air plasma spraying. The combined effect of thermal shock and hot corrosion on the failure of TBCs was highlighted investigated. The results showed that the combined effect of hot corrosion and thermal shock was prone to induce the failure of TBCs. The main failure of TBCs under the combined effect was in the form of penetrating crack to the bondcoat/substrate interface and oxidation at the penetrating crack front. ","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127868416","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}
Metal materials are the most important material materials for humandevelopment and progress. In major scientific and technological fields such asindustry, agriculture, and national defense, corresponding metal materials are used according to different functions and uses. This paper analyzes the common problems in the detection of metal materials, in order to provide suggestions for the related application of metal materials.
{"title":"Common Problems in Metal Material Testing and Solutions","authors":"Xiang-Ran Du","doi":"10.30564/jmmr.v1i1.192","DOIUrl":"https://doi.org/10.30564/jmmr.v1i1.192","url":null,"abstract":"Metal materials are the most important material materials for humandevelopment and progress. In major scientific and technological fields such asindustry, agriculture, and national defense, corresponding metal materials are used according to different functions and uses. This paper analyzes the common problems in the detection of metal materials, in order to provide suggestions for the related application of metal materials.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"16 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116791754","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}
In the thermal processing of metal materials, the performance of thematerial is more stable, and the heat-treated materials are processed into parts to make the performance more excellent and more in line with the performance requirements of mechanical parts. However, in thermal processing, metal materials are prone to problems, such as deformation, deformation of the appearance of metal materials, and fatal effects on the processing of mechanical parts. Therefore, this paper focuses on solving the causes of deformation in the thermal processing of metal materials, as well as solutions to improve the problems in the processing of metal materials.
{"title":"Influencing Factors and Control Strategies of Heat Treatment Deformation of Metal Materials","authors":"Qiang Li, Yutao Wang","doi":"10.30564/jmmr.v1i1.190","DOIUrl":"https://doi.org/10.30564/jmmr.v1i1.190","url":null,"abstract":"In the thermal processing of metal materials, the performance of thematerial is more stable, and the heat-treated materials are processed into parts to make the performance more excellent and more in line with the performance requirements of mechanical parts. However, in thermal processing, metal materials are prone to problems, such as deformation, deformation of the appearance of metal materials, and fatal effects on the processing of mechanical parts. Therefore, this paper focuses on solving the causes of deformation in the thermal processing of metal materials, as well as solutions to improve the problems in the processing of metal materials.","PeriodicalId":232294,"journal":{"name":"Journal of Metallic Material Research","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114840621","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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