Abstract The paper deals with determining the final value of simple systems reliability. Simple systems, the systems with simple interconnections, can be divided into a sequence of series and/or parallel subsystems. The paper presents the basic functional relationships used to assess the reliability of simple systems, however, they are also essential for understanding more complex systems. The paper graphically shows and analyzes the final reliability of the systems depending on the arrangement of subsystems, and also those depending on the number of subsystems.
{"title":"Reliability Assessment of the Systems with Simple Interconnections","authors":"E. Labašová","doi":"10.2478/rput-2021-0022","DOIUrl":"https://doi.org/10.2478/rput-2021-0022","url":null,"abstract":"Abstract The paper deals with determining the final value of simple systems reliability. Simple systems, the systems with simple interconnections, can be divided into a sequence of series and/or parallel subsystems. The paper presents the basic functional relationships used to assess the reliability of simple systems, however, they are also essential for understanding more complex systems. The paper graphically shows and analyzes the final reliability of the systems depending on the arrangement of subsystems, and also those depending on the number of subsystems.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84205219","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 contains the design and implementation of a system for automatic program generation for an industrial robot, based on the graphical input recorded by camera. The content is divided into two parts. The first section deals with processing the visual data acquired from an external source to appropriate form, using edge identification and transformation from raster to vector image. The second part deals with the automatic program generation for industrial robot. The article describes different possible approaches to solution. The selected way of solution was implemented in real environment in a chosen programming language. The final section of the article presents the results of experiments, together with the overall evaluation of the results.
{"title":"An Approach to Automated Programming of Industrial Robots Based on Graphic Data","authors":"I. Halenár, Lenka Halenárová, M. Kovacic","doi":"10.2478/rput-2021-0026","DOIUrl":"https://doi.org/10.2478/rput-2021-0026","url":null,"abstract":"Abstract The article contains the design and implementation of a system for automatic program generation for an industrial robot, based on the graphical input recorded by camera. The content is divided into two parts. The first section deals with processing the visual data acquired from an external source to appropriate form, using edge identification and transformation from raster to vector image. The second part deals with the automatic program generation for industrial robot. The article describes different possible approaches to solution. The selected way of solution was implemented in real environment in a chosen programming language. The final section of the article presents the results of experiments, together with the overall evaluation of the results.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89966159","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}
P. Rantuch, J. Martinka, Tomáš Štefko, Igor Wachter
Abstract Polymeric materials, which are currently very often used in various industries, are often transported and stored in the form of granules before processing. This method has several advantages, but in most studies the test samples are modified to different shapes and dimensions. This paper is therefore focused on the initiation of selected granular plastics. Samples of five polymeric materials were exposed to an external heat flux from 20 kW.m−2 to 40 kW.m−2. A spark initiator was used to ignite the released gaseous products of thermal decomposition of the polymer sample. FTP (flow-time product) method was applied to the obtained parameter - time to ignition, from which other initiation parameters were determined. The critical heat flux was determined in the range of 5.0 kW.m−2 - 11.8 kW.m−2. Despite the relatively small thickness (4 mm), the samples behaved as thermally thick. During the measurement, thin surface layer melted, and the rest of the polymer remained in its original granulated form. Ignition temperatures were calculated according to the Stefan-Boltzmann’s law between 273 °C - 402 °C.
{"title":"Initiation Parameters of Granulated Synthetic Polymers","authors":"P. Rantuch, J. Martinka, Tomáš Štefko, Igor Wachter","doi":"10.2478/rput-2021-0012","DOIUrl":"https://doi.org/10.2478/rput-2021-0012","url":null,"abstract":"Abstract Polymeric materials, which are currently very often used in various industries, are often transported and stored in the form of granules before processing. This method has several advantages, but in most studies the test samples are modified to different shapes and dimensions. This paper is therefore focused on the initiation of selected granular plastics. Samples of five polymeric materials were exposed to an external heat flux from 20 kW.m−2 to 40 kW.m−2. A spark initiator was used to ignite the released gaseous products of thermal decomposition of the polymer sample. FTP (flow-time product) method was applied to the obtained parameter - time to ignition, from which other initiation parameters were determined. The critical heat flux was determined in the range of 5.0 kW.m−2 - 11.8 kW.m−2. Despite the relatively small thickness (4 mm), the samples behaved as thermally thick. During the measurement, thin surface layer melted, and the rest of the polymer remained in its original granulated form. Ignition temperatures were calculated according to the Stefan-Boltzmann’s law between 273 °C - 402 °C.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79649973","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}
J. Michálek, K. Domnina, Veronika Kvorková, Kristína Šefčovičová, Klaudia Mončeková, M. Soldán
Abstract The usage of the low-cost catalysts for methylene blue removal from wastewater was investigated. Heterogeneous Fenton-like process consists of the use of a hydrogen peroxide solution, and an iron-rich catalyst, red mud and black nickel mud were used for that purpose. The factors such as the catalyst dose and the hydrogen peroxide solution volume were monitored. The results of experiments showed that the degradation of methylene blue dye in Fenton-like oxidation process using selected catalysts can be described by a pseudo-second-order kinetic model. The highest dye removal efficiency (87.15 %) was achieved using the black nickel mud catalyst after 30 minutes of reaction.
{"title":"Heterogeneous Fenton-Like Oxidation of Methylene Blue Using Alternative Catalysts","authors":"J. Michálek, K. Domnina, Veronika Kvorková, Kristína Šefčovičová, Klaudia Mončeková, M. Soldán","doi":"10.2478/rput-2021-0009","DOIUrl":"https://doi.org/10.2478/rput-2021-0009","url":null,"abstract":"Abstract The usage of the low-cost catalysts for methylene blue removal from wastewater was investigated. Heterogeneous Fenton-like process consists of the use of a hydrogen peroxide solution, and an iron-rich catalyst, red mud and black nickel mud were used for that purpose. The factors such as the catalyst dose and the hydrogen peroxide solution volume were monitored. The results of experiments showed that the degradation of methylene blue dye in Fenton-like oxidation process using selected catalysts can be described by a pseudo-second-order kinetic model. The highest dye removal efficiency (87.15 %) was achieved using the black nickel mud catalyst after 30 minutes of reaction.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90470448","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}
J. Martinka, P. Rantuch, Igor Wachter, Tomáš Štefko, M. Trčka, Martina Hladová, A. Nečas, Janka Sulová
Abstract This study deals with the Fire Growth Rate Index (FIGRA) as a key fire characteristic of electrical cables (determined by a cone calorimeter) that allows to estimate their reaction to fire class. Three power (supply) electrical cables (reaction to fire class B2ca) were tested by a cone calorimeter using different heat fluxes of 20, 30, 40 a 50 kW·m−2. The cables were three-wire (cross-section of each wire was 1.5 mm2) with a nominal voltage of 0.6 kV (alternating current), resp. 1 kV (direct current). The cable sheaths were made of an ethylene copolymer filled with aluminum hydroxide. The beddings were made of an ethylene copolymer filled with a mixture of aluminum hydroxide and calcium carbonate. The conductor insulations of one electrical cable were made of crosslinked polyethylene and the conductor insulations of the other two electrical cables were made of an ethylene copolymer filled with aluminum hydroxide. FIGRA was determined per unit length and unit area of electrical cables. FIGRA increased with increasing heat flux. At a heat flux of 50 kW·m−2, all the electric cables examined showed a very similar FIGRA (from 0.19 to 0.21 kW·m−1·s−1 and 18.4 to 21.2 kW·m−1·s−1, respectively). Conversely, at a heat flux of 20 kW·m−2, the investigated cables showed greater FIGRA variance (in the range of 0.11 to 0.16 kW·m−1·s−1 or 10.8 to 16.2 kW·m−1·s−1).
{"title":"Fire Growth Rate Index as a Key Fire Characteristic of Electrical Cables","authors":"J. Martinka, P. Rantuch, Igor Wachter, Tomáš Štefko, M. Trčka, Martina Hladová, A. Nečas, Janka Sulová","doi":"10.2478/rput-2021-0008","DOIUrl":"https://doi.org/10.2478/rput-2021-0008","url":null,"abstract":"Abstract This study deals with the Fire Growth Rate Index (FIGRA) as a key fire characteristic of electrical cables (determined by a cone calorimeter) that allows to estimate their reaction to fire class. Three power (supply) electrical cables (reaction to fire class B2ca) were tested by a cone calorimeter using different heat fluxes of 20, 30, 40 a 50 kW·m−2. The cables were three-wire (cross-section of each wire was 1.5 mm2) with a nominal voltage of 0.6 kV (alternating current), resp. 1 kV (direct current). The cable sheaths were made of an ethylene copolymer filled with aluminum hydroxide. The beddings were made of an ethylene copolymer filled with a mixture of aluminum hydroxide and calcium carbonate. The conductor insulations of one electrical cable were made of crosslinked polyethylene and the conductor insulations of the other two electrical cables were made of an ethylene copolymer filled with aluminum hydroxide. FIGRA was determined per unit length and unit area of electrical cables. FIGRA increased with increasing heat flux. At a heat flux of 50 kW·m−2, all the electric cables examined showed a very similar FIGRA (from 0.19 to 0.21 kW·m−1·s−1 and 18.4 to 21.2 kW·m−1·s−1, respectively). Conversely, at a heat flux of 20 kW·m−2, the investigated cables showed greater FIGRA variance (in the range of 0.11 to 0.16 kW·m−1·s−1 or 10.8 to 16.2 kW·m−1·s−1).","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89420269","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}
Zuzana Szabová, R. Kuracina, M. Mynarz, Marián Škvarka
Abstract A standardized device with a volume of 1 m3 or 20 L is used to determine explosion parameters. An explosion chamber where explosion takes place is of a spherical or cylindrical shape that suits the shape of a cubic container. In the case of a cylindrical vessel, the diameter and depth of the vessel are 1: 1. In this case, it is a spherical vessel with a volume of 365 liters. Time parameters of the disperser in the spherical vessel are compared with those of a truncated spherical vessel with a volume of 291 liters. Comparison of the measurement results showed that the optimal delay time of the explosion chamber with a volume of 291 liters is 290 ms, while the delay time of the explosion chamber with a volume of 365 liters is 350 ms.
{"title":"Influence of Explosion Chamber Shape on Timing Parameters of Disperser","authors":"Zuzana Szabová, R. Kuracina, M. Mynarz, Marián Škvarka","doi":"10.2478/rput-2021-0015","DOIUrl":"https://doi.org/10.2478/rput-2021-0015","url":null,"abstract":"Abstract A standardized device with a volume of 1 m3 or 20 L is used to determine explosion parameters. An explosion chamber where explosion takes place is of a spherical or cylindrical shape that suits the shape of a cubic container. In the case of a cylindrical vessel, the diameter and depth of the vessel are 1: 1. In this case, it is a spherical vessel with a volume of 365 liters. Time parameters of the disperser in the spherical vessel are compared with those of a truncated spherical vessel with a volume of 291 liters. Comparison of the measurement results showed that the optimal delay time of the explosion chamber with a volume of 291 liters is 290 ms, while the delay time of the explosion chamber with a volume of 365 liters is 350 ms.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86861154","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 EN 14034 standard defines the requirements for igniter, to determine the properties of dust clouds. The standard specifies the conditions for occurrence of explosions of dust clouds. According to the standard, equipment with a volume of 1m3 and 20L can be used to determine the explosion parameters of dispersed dusts. The equipment has the time parameters of dispersing and the ignition system defined in the Standard. Experimental determination of time parameters is required for a different chamber volume. The article therefore deals with the determination of parameters for dispersing system in the 291 litre chamber. Determination of igniter delay was performed on the base of setting the time relay. Activation of pressurised air flow was determined by calculation, and it was subsequently experimentally verified in laboratory conditions. A video camera recording was selected for measuring the rate of nitrocellulose ignition from the resistance wire. The result of this study is determination of the igniter timing in dependence of the explosion chamber volume. The time delay of the nitrocellulose igniter is 320 ms.
{"title":"Determination of Timing Parameters of Dust Clouds Explosion in Dependence on the Size of the Vessel Volume","authors":"R. Kuracina, Zuzana Szabová","doi":"10.2478/rput-2021-0005","DOIUrl":"https://doi.org/10.2478/rput-2021-0005","url":null,"abstract":"Abstract EN 14034 standard defines the requirements for igniter, to determine the properties of dust clouds. The standard specifies the conditions for occurrence of explosions of dust clouds. According to the standard, equipment with a volume of 1m3 and 20L can be used to determine the explosion parameters of dispersed dusts. The equipment has the time parameters of dispersing and the ignition system defined in the Standard. Experimental determination of time parameters is required for a different chamber volume. The article therefore deals with the determination of parameters for dispersing system in the 291 litre chamber. Determination of igniter delay was performed on the base of setting the time relay. Activation of pressurised air flow was determined by calculation, and it was subsequently experimentally verified in laboratory conditions. A video camera recording was selected for measuring the rate of nitrocellulose ignition from the resistance wire. The result of this study is determination of the igniter timing in dependence of the explosion chamber volume. The time delay of the nitrocellulose igniter is 320 ms.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90451405","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}
Zuzana Sanny, Alexandra Kucmanová, K. Gerulová, Lenka Gabrišová
Abstract Over the last few decades, nanotechnologies have gained a great deal of attention, and various nanomaterials and techniques have been developed for water remediation. This study deals with the adsorption of Naphthol green B onto the magnetite nanoparticles synthetized by the coprecipitation method at the laboratory temperature. According to the obtained results, the sorption process is obvious only at the acidic condition when the pH of solution decreases to pH level 3. According to nonlinear fit of experimental data, the sorption of the Naphthol green B onto magnetite nanoparticles is assumed as multilayer, while the Freundlich model fits better (96.158 %) than the Langmuir model does (55.941 %).
{"title":"Potential Applications of Nanomaterials in Wastewater Treatment","authors":"Zuzana Sanny, Alexandra Kucmanová, K. Gerulová, Lenka Gabrišová","doi":"10.2478/rput-2021-0013","DOIUrl":"https://doi.org/10.2478/rput-2021-0013","url":null,"abstract":"Abstract Over the last few decades, nanotechnologies have gained a great deal of attention, and various nanomaterials and techniques have been developed for water remediation. This study deals with the adsorption of Naphthol green B onto the magnetite nanoparticles synthetized by the coprecipitation method at the laboratory temperature. According to the obtained results, the sorption process is obvious only at the acidic condition when the pH of solution decreases to pH level 3. According to nonlinear fit of experimental data, the sorption of the Naphthol green B onto magnetite nanoparticles is assumed as multilayer, while the Freundlich model fits better (96.158 %) than the Langmuir model does (55.941 %).","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72627932","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 study was focused on describing ultraviolet-visible spectra of the humic substances, humic acids and fulvic acids isolated from four Slovak soils. The samples were heated in a laboratory furnace, to simulate soil behaviour during fires. The absorbances at the wavelengths corresponding to the selected chromophores and specific wavelength for groups of substances were compared. Analysis of the UV -VIS spectra of the extracted humic substances may indicate the directions of interest in the changes in soil organic matter, along with the changes in external conditions, such as natural fires.
{"title":"Study Into the Changes in Soil Organic Matter, Caused By Laboratory Simulated Fires in Four Slovak Soils 1. UV-VIS Spectrum Analysis","authors":"Maroš Sirotiak, Alica Pastierová, L. Blinová","doi":"10.2478/rput-2021-0014","DOIUrl":"https://doi.org/10.2478/rput-2021-0014","url":null,"abstract":"Abstract The study was focused on describing ultraviolet-visible spectra of the humic substances, humic acids and fulvic acids isolated from four Slovak soils. The samples were heated in a laboratory furnace, to simulate soil behaviour during fires. The absorbances at the wavelengths corresponding to the selected chromophores and specific wavelength for groups of substances were compared. Analysis of the UV -VIS spectra of the extracted humic substances may indicate the directions of interest in the changes in soil organic matter, along with the changes in external conditions, such as natural fires.","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74438724","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 amount of generated e-waste during the last decades has been steadily raising to the point at which it is highly desirable to obtain the precious metals by recycling the e-waste without the need of exploiting the environment. The rapid development of technology, steep growth of modern facilities with user-friendly electronical devices and a stiff competition between manufacturers are among the main reasons for decreasing the life span of such devices, and subsequently end up as an obsolete waste product. Rapid industrialization and urbanization have also caused many environmental problems, e.g. heavy metal contamination. Silver is one of the precious metals with exceptionally high industrial applications, which makes it an area of research of high interest. Demand for silver continues to grow with progress in the industrialized world, while the world reserves of high-quality silver ores are declining. Although, there are large stocks of low and lean quality silver ores still to be mined, the main goal of this article is to provide a simple, effective and eco-friendly method of silver recovery from e-waste, e.g. electrical circuit breakers using an electrochemical cell. After 20.75 days of the experiment, 1481.5 grams of silver contacts were processed with a final yield of 61.41 % grams of silver dendrite crystals (99.9 % purity).
{"title":"Electrochemical Recovery of Silver Using a Simple Cell","authors":"Igor Wachter, Tomáš Štefko","doi":"10.2478/rput-2021-0017","DOIUrl":"https://doi.org/10.2478/rput-2021-0017","url":null,"abstract":"Abstract The amount of generated e-waste during the last decades has been steadily raising to the point at which it is highly desirable to obtain the precious metals by recycling the e-waste without the need of exploiting the environment. The rapid development of technology, steep growth of modern facilities with user-friendly electronical devices and a stiff competition between manufacturers are among the main reasons for decreasing the life span of such devices, and subsequently end up as an obsolete waste product. Rapid industrialization and urbanization have also caused many environmental problems, e.g. heavy metal contamination. Silver is one of the precious metals with exceptionally high industrial applications, which makes it an area of research of high interest. Demand for silver continues to grow with progress in the industrialized world, while the world reserves of high-quality silver ores are declining. Although, there are large stocks of low and lean quality silver ores still to be mined, the main goal of this article is to provide a simple, effective and eco-friendly method of silver recovery from e-waste, e.g. electrical circuit breakers using an electrochemical cell. After 20.75 days of the experiment, 1481.5 grams of silver contacts were processed with a final yield of 61.41 % grams of silver dendrite crystals (99.9 % purity).","PeriodicalId":21013,"journal":{"name":"Research Papers Faculty of Materials Science and Technology Slovak University of Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74549167","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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