Firas Jawad Kadhim, Musab Sabah Abed, Jwad K. Almusawi
Abstract Re-using waste generated from daily domestic usage to improve weak soils such as dune sand gives a profitable solution to both environment and the construction sector. In this paper, weak sandy soil was modified with two types of fibers derived from daily domestic use. Plastic bottle waste fiber and tainted polypropylene sediment filter fiber were embedded in the sandy soil with a rate of (0.5%,1%,1.5%, and 2%) by weight of dry soil. Toward this, the direct shear test was conducted to confirm the optimum fiber content and evaluate other parameters such as shear strength, normalized ultimate shear strength, angle of internal friction, and adhesion. The results showed that the 1.5% fiber content showed higher values of angle of internal friction and the normalized ultimate shear strength for both types of fibers. The reinforcement with plastic bottle waste fiber and tainted polypropylene sediment filter fiber enhanced the shear strength parameters and normalized ultimate shear strength. Significant improvement was noticed in the adhesion value with the addition of 2% of tainted polypropylene sediment filter fiber. finally, the effect of fiber addition on the Mohr-coulomb failure envelope was discussed.
{"title":"Feasibility of Strengthening Sandy Soils Using Industry Waste as Geo-Fiber","authors":"Firas Jawad Kadhim, Musab Sabah Abed, Jwad K. Almusawi","doi":"10.2478/cee-2023-0059","DOIUrl":"https://doi.org/10.2478/cee-2023-0059","url":null,"abstract":"Abstract Re-using waste generated from daily domestic usage to improve weak soils such as dune sand gives a profitable solution to both environment and the construction sector. In this paper, weak sandy soil was modified with two types of fibers derived from daily domestic use. Plastic bottle waste fiber and tainted polypropylene sediment filter fiber were embedded in the sandy soil with a rate of (0.5%,1%,1.5%, and 2%) by weight of dry soil. Toward this, the direct shear test was conducted to confirm the optimum fiber content and evaluate other parameters such as shear strength, normalized ultimate shear strength, angle of internal friction, and adhesion. The results showed that the 1.5% fiber content showed higher values of angle of internal friction and the normalized ultimate shear strength for both types of fibers. The reinforcement with plastic bottle waste fiber and tainted polypropylene sediment filter fiber enhanced the shear strength parameters and normalized ultimate shear strength. Significant improvement was noticed in the adhesion value with the addition of 2% of tainted polypropylene sediment filter fiber. finally, the effect of fiber addition on the Mohr-coulomb failure envelope was discussed.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139014444","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}
Abstract Numerous problems that can occur during regular building use may necessitate the need for reinforced concrete RC members to be strengthened. An increase in live loads or structural damage is two examples. Various techniques can be used to increase load-carrying capability. Concrete reinforcement with textile-carbon fiber (TCF) is a more recent option. For almost all active forces, this strengthening procedure is appropriate. For bending, shear, torsion, or axial forces, strengthening is an option. The experimental work for this study examined the impact of textile carbon mesh in reinforced concrete with various numbers of layers and sikadure-330 as the bonding material with different damage ratio (0%, 45%, 55% and 70%). As well as the flexural behavior of reinforced concrete beams strengthened with TCF, by casting and testing 13 beams under the monotonic load, one of them represented the control beam, they designed according to ACI 318-14 to ensure flexural failure. From the results obtained in this study it was shown that the flexural capacity of all strengthened beams increased as a consequence of TCF strengthening. Therefore, TCF jacketing is a very promising technique for increasing reinforced concrete flexural capability, which is necessary for retrofitting and strengthening.
{"title":"Strengthening of Reinforced Concrete Beams with Textile-Reinforced Concrete","authors":"Marwa Abd-Al-Naser, Ibrahim S. I. Harba","doi":"10.2478/cee-2023-0054","DOIUrl":"https://doi.org/10.2478/cee-2023-0054","url":null,"abstract":"Abstract Numerous problems that can occur during regular building use may necessitate the need for reinforced concrete RC members to be strengthened. An increase in live loads or structural damage is two examples. Various techniques can be used to increase load-carrying capability. Concrete reinforcement with textile-carbon fiber (TCF) is a more recent option. For almost all active forces, this strengthening procedure is appropriate. For bending, shear, torsion, or axial forces, strengthening is an option. The experimental work for this study examined the impact of textile carbon mesh in reinforced concrete with various numbers of layers and sikadure-330 as the bonding material with different damage ratio (0%, 45%, 55% and 70%). As well as the flexural behavior of reinforced concrete beams strengthened with TCF, by casting and testing 13 beams under the monotonic load, one of them represented the control beam, they designed according to ACI 318-14 to ensure flexural failure. From the results obtained in this study it was shown that the flexural capacity of all strengthened beams increased as a consequence of TCF strengthening. Therefore, TCF jacketing is a very promising technique for increasing reinforced concrete flexural capability, which is necessary for retrofitting and strengthening.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139016260","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}
H. Al-Hamaiedeh, S. Aljbour, T. El-Hasan, Tuqa Almrayat, Ziad Al-Ghazawi
Abstract This research aims to look into a sustainable technique for the treatment, reuse and disposal of domestic sewage sludge (DSS). The purpose of the study was to examine the operating factors that influence the calorific value of the produced biochar from the pyrolysis of DSS. Based on the analysis of the full factorial design, the impacts of the pyrolysis conditions, specifically: temperature, heating rate, and isothermal time on the calorific value of biochar were evaluated. When the pyrolysis temperature was raised from 300 to 500 oC, the calorific value of biochar was decreased by 34%. A 14% decrease in the calorific content of the biochar was also noticed when the heating rate was increased from 5 to 35 oC/min. When the isothermal time was increased from 45 to 120 minutes, the calorific value of the biochar remained essentially unchanged. No interaction effects among process variables were found using the factorial design methodology. A first-order regression model was developed to predict the calorific value of biochar using the magnitude of the effects of the process factors and their interactions. The model predictions agreed very well with the obtained experimental results.
{"title":"Pyrolysis of Domestic Sewage Sludge: Effect of Process Parameters on Biochar Calorific Value","authors":"H. Al-Hamaiedeh, S. Aljbour, T. El-Hasan, Tuqa Almrayat, Ziad Al-Ghazawi","doi":"10.2478/cee-2023-0058","DOIUrl":"https://doi.org/10.2478/cee-2023-0058","url":null,"abstract":"Abstract This research aims to look into a sustainable technique for the treatment, reuse and disposal of domestic sewage sludge (DSS). The purpose of the study was to examine the operating factors that influence the calorific value of the produced biochar from the pyrolysis of DSS. Based on the analysis of the full factorial design, the impacts of the pyrolysis conditions, specifically: temperature, heating rate, and isothermal time on the calorific value of biochar were evaluated. When the pyrolysis temperature was raised from 300 to 500 oC, the calorific value of biochar was decreased by 34%. A 14% decrease in the calorific content of the biochar was also noticed when the heating rate was increased from 5 to 35 oC/min. When the isothermal time was increased from 45 to 120 minutes, the calorific value of the biochar remained essentially unchanged. No interaction effects among process variables were found using the factorial design methodology. A first-order regression model was developed to predict the calorific value of biochar using the magnitude of the effects of the process factors and their interactions. The model predictions agreed very well with the obtained experimental results.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139020761","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}
Abstract Geogrid-reinforced earth retaining walls used to improve soil quality, and provide additional shear strength in the soil mass through the tensile strength in the reinforcement layers. A numerical model was developed by finite element code PLAXIS2D, of a segmental facing geogrid-reinforced retaining wall. This research has been carried out to investigate the effect of loading increments, loading increments width, loading increments location, facing inclination angle, geogrid inclination angle, and geogrid-soil friction factor, on the behaviour of a geogrid-reinforced soil retaining wall. The results show that the failure plane occurred in the reinforced zone at the mid-height, this observation contradicted the triangular distribution with depth assumed in conception methodologies for reinforced soil retaining wall. The distribution of peak tensile strength with depth was bilinear at high loading increments and became trapezoidal at low loading ones. Furthermore, it was found that the behaviour of a geogrid-reinforced soil retaining wall is independent of loading increments width beyond 0.5H. It also seems that the loading increments location can change the shape and the position of the peak tensile strength. It also seems that the geogrid inclination angle has a major effect on the lateral facing displacements and safety factor.
{"title":"Tensile Force Distribution And Development Within Geogrid-Reinforced Retaining Wall","authors":"Marwa Feligha, Fatima Zohra Benamara, Nouaouria Mohamed Salah, S. Bekkouche, Benayoun Fadila","doi":"10.2478/cee-2023-0049","DOIUrl":"https://doi.org/10.2478/cee-2023-0049","url":null,"abstract":"Abstract Geogrid-reinforced earth retaining walls used to improve soil quality, and provide additional shear strength in the soil mass through the tensile strength in the reinforcement layers. A numerical model was developed by finite element code PLAXIS2D, of a segmental facing geogrid-reinforced retaining wall. This research has been carried out to investigate the effect of loading increments, loading increments width, loading increments location, facing inclination angle, geogrid inclination angle, and geogrid-soil friction factor, on the behaviour of a geogrid-reinforced soil retaining wall. The results show that the failure plane occurred in the reinforced zone at the mid-height, this observation contradicted the triangular distribution with depth assumed in conception methodologies for reinforced soil retaining wall. The distribution of peak tensile strength with depth was bilinear at high loading increments and became trapezoidal at low loading ones. Furthermore, it was found that the behaviour of a geogrid-reinforced soil retaining wall is independent of loading increments width beyond 0.5H. It also seems that the loading increments location can change the shape and the position of the peak tensile strength. It also seems that the geogrid inclination angle has a major effect on the lateral facing displacements and safety factor.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138988578","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}
Abstract The expert research activity of transition zones of tunnels is one part of the overall set of these places on the railway line. Typical places where the stiffness of the railway changes are the portals of tunnels, where undesirable deformations occur during the operation of trainsets due to the changes in materials. In the places of the portals, there can be a ballastless track or slab track (with concrete bearing layer) or classic structure with a railway ballast. The paper presents long-term research on monitoring height changes in these sections. The results of the expert activity will be the basis for the subsequent proposal of new measures, i.e. changes to built-in objects or modification of the materials of structural layers in a given place of the transition zone.
{"title":"Experimental Monitoring of Transition Zones in Railway Tunnels","authors":"S. Hodas, A. Pultznerová, Erik Vrchovsky","doi":"10.2478/cee-2023-0042","DOIUrl":"https://doi.org/10.2478/cee-2023-0042","url":null,"abstract":"Abstract The expert research activity of transition zones of tunnels is one part of the overall set of these places on the railway line. Typical places where the stiffness of the railway changes are the portals of tunnels, where undesirable deformations occur during the operation of trainsets due to the changes in materials. In the places of the portals, there can be a ballastless track or slab track (with concrete bearing layer) or classic structure with a railway ballast. The paper presents long-term research on monitoring height changes in these sections. The results of the expert activity will be the basis for the subsequent proposal of new measures, i.e. changes to built-in objects or modification of the materials of structural layers in a given place of the transition zone.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139013928","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}
Filip Gago, Ján Mihálik, S. Masarovicová, Jozef Vlček, Vojtěch Boltnar, Lukáš Uličný
Abstract The interaction between soil and building structures of various materials is defined on the basis of certain assumptions, but these are shown in many cases to be not accurate from the point of view of safe, reliable and economic design of engineering structures. Therefore, as part of our research activities, we decided to better understand the transfer of shear forces and the interaction between soil and other materials. We focused on testing materials in a shear box apparatus, where 3 types of tests were carried out: in the first stage, we tested the shear parameters of the soil in a 900 mm2 box apparatus; in the second stage, the properties of the interaction between soil and concrete were tested, and in the third stage, soil was in contact with the steel plate. The results of the tests are within the expected range of the interface friction angle between the structures and the soils.
{"title":"Large Scale Shear Box Testing of Interface Between Construction Materials and Soils","authors":"Filip Gago, Ján Mihálik, S. Masarovicová, Jozef Vlček, Vojtěch Boltnar, Lukáš Uličný","doi":"10.2478/cee-2023-0065","DOIUrl":"https://doi.org/10.2478/cee-2023-0065","url":null,"abstract":"Abstract The interaction between soil and building structures of various materials is defined on the basis of certain assumptions, but these are shown in many cases to be not accurate from the point of view of safe, reliable and economic design of engineering structures. Therefore, as part of our research activities, we decided to better understand the transfer of shear forces and the interaction between soil and other materials. We focused on testing materials in a shear box apparatus, where 3 types of tests were carried out: in the first stage, we tested the shear parameters of the soil in a 900 mm2 box apparatus; in the second stage, the properties of the interaction between soil and concrete were tested, and in the third stage, soil was in contact with the steel plate. The results of the tests are within the expected range of the interface friction angle between the structures and the soils.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139020843","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}
{"title":"Retraction","authors":"","doi":"10.2478/cee-2023-0041","DOIUrl":"https://doi.org/10.2478/cee-2023-0041","url":null,"abstract":"","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135444047","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}
Abstract The performance/weight ratio of fiber reinforced polymer matrix composites makes them the material of choice for structural applications in many fields such as aerospace, aeronautics, automotive and civil engineering...etc. In polymer matrix composites, the fibers used as reinforcement are mainly synthetic fibers such as carbon and/or glass fibers. To ensure the low cost of using fiber-reinforced materials in motor vehicles, it is proposed to selectively incorporate carbon fibers to enhance glass fiber composites along the roadway, and to enhance glass fiber composites along the main load path. For this purpose, we conducted a behavioral study of hybrid epoxy thermoset polymer matrix laminates to highlight the influence of alternate hybridization of glass and carbon fibers on the physical-mechanical behavior of the materials.The results obtained show that the alternated hybridation of the fibers has a significant influence on the tensile properties; and it affected the density, hardness and flexural properties significantly.
{"title":"Effect of Alternating Hybridisation of Fibres on the Physico - Mechanical Behaviour of Composite Materials","authors":"N. Harb, H. Dilmi, B. Bezzazi, Kahina Hamitouche","doi":"10.2478/cee-2023-0036","DOIUrl":"https://doi.org/10.2478/cee-2023-0036","url":null,"abstract":"Abstract The performance/weight ratio of fiber reinforced polymer matrix composites makes them the material of choice for structural applications in many fields such as aerospace, aeronautics, automotive and civil engineering...etc. In polymer matrix composites, the fibers used as reinforcement are mainly synthetic fibers such as carbon and/or glass fibers. To ensure the low cost of using fiber-reinforced materials in motor vehicles, it is proposed to selectively incorporate carbon fibers to enhance glass fiber composites along the roadway, and to enhance glass fiber composites along the main load path. For this purpose, we conducted a behavioral study of hybrid epoxy thermoset polymer matrix laminates to highlight the influence of alternate hybridization of glass and carbon fibers on the physical-mechanical behavior of the materials.The results obtained show that the alternated hybridation of the fibers has a significant influence on the tensile properties; and it affected the density, hardness and flexural properties significantly.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41265481","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}
B. Yasin, Dana Qi’dan, Safa Al-Olimat, Mo’men Ayasrah, Hatem H. Almasaeid
Abstract The current study employs the finite element method to compare stress concentration pertaining to a graphite / epoxy rectangular laminated composite plate that possess holes in different shapes. The hole enables redistributing in-plane stresses, impacts the stress concentration factor (SCF), and focuses maximum stress near the hole. The ANSYS program has been designed to be employed for parametric studies pertaining to plates that have a hole under uniaxial in-plane load. Analysis was done for angle-ply, four-layered symmetrically laminated rectangular plates that include different stacking sequences ± θ.
{"title":"Effect of the Fibre Orientation Angles on Stress Concentration Around Various Shapes of Hole in Laminated Composite Plate Subject to in - Plane Loading","authors":"B. Yasin, Dana Qi’dan, Safa Al-Olimat, Mo’men Ayasrah, Hatem H. Almasaeid","doi":"10.2478/cee-2023-0019","DOIUrl":"https://doi.org/10.2478/cee-2023-0019","url":null,"abstract":"Abstract The current study employs the finite element method to compare stress concentration pertaining to a graphite / epoxy rectangular laminated composite plate that possess holes in different shapes. The hole enables redistributing in-plane stresses, impacts the stress concentration factor (SCF), and focuses maximum stress near the hole. The ANSYS program has been designed to be employed for parametric studies pertaining to plates that have a hole under uniaxial in-plane load. Analysis was done for angle-ply, four-layered symmetrically laminated rectangular plates that include different stacking sequences ± θ.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44033080","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}
Abstract The article attempts to assess the possibility of using non-woven fabrics made of waste fibers in cladding panels. For this purpose, woolen and polypropylene nonwovens were tested for mass per unit area, characteristic opening size, and lengthwise and crosswise elongation at maximum strength. Non-woven fabrics were placed in the middle of the thickness of cement and gypsum boards and subjected to tests of density, thermal conductivity coefficient λ, and bending strength. The influence of individual nonwoven fabrics with different properties on the properties of the finished composite was determined. It was found that wool nonwoven fabrics had the best effect on the thermal conductivity coefficient. A better affinity for nonwoven fabrics was shown by gypsum mortar. The best influence on the bending strength of the panels had polyester non-woven fabrics with the lowest mass per unit area and the largest characteristic opening size.
{"title":"Testing the Properties of Cement and Gypsum Boards Reinforced with Nonwoven Fabrics Made of Waste and Recycled Fibres","authors":"W. Brachaczek, Adam Chleboś","doi":"10.2478/cee-2023-0032","DOIUrl":"https://doi.org/10.2478/cee-2023-0032","url":null,"abstract":"Abstract The article attempts to assess the possibility of using non-woven fabrics made of waste fibers in cladding panels. For this purpose, woolen and polypropylene nonwovens were tested for mass per unit area, characteristic opening size, and lengthwise and crosswise elongation at maximum strength. Non-woven fabrics were placed in the middle of the thickness of cement and gypsum boards and subjected to tests of density, thermal conductivity coefficient λ, and bending strength. The influence of individual nonwoven fabrics with different properties on the properties of the finished composite was determined. It was found that wool nonwoven fabrics had the best effect on the thermal conductivity coefficient. A better affinity for nonwoven fabrics was shown by gypsum mortar. The best influence on the bending strength of the panels had polyester non-woven fabrics with the lowest mass per unit area and the largest characteristic opening size.","PeriodicalId":42034,"journal":{"name":"Civil and Environmental Engineering","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49089596","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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