Pub Date : 2024-09-09DOI: 10.3103/s0967091224700293
E. N. Tyulenev, V. P. Glebov, G. N. Kononykhin, A. N. Rogotovsky, A. A. Shipel’nikov, N. A. Bobyleva
Abstract
Results of computational experiments on studying multiphase flow and interphase interaction in the volume of an industrial 50-ton tundish of a continuous caster, including when blowing with argon through bottom blowing blocks, are presented. A mathematical model has been developed that makes it possible to predict the dynamics of melt mixing at a given casting speed. The pattern of influence of the layout of the ladle’s working space on the area of “stagnant zones” in the ladle volume has been found.
{"title":"Study of the Influence of Turbo Stops on Peculiarities of Bath Hydrodynamics in 50-Ton Tundish Ladles of Continuous Casting Machines","authors":"E. N. Tyulenev, V. P. Glebov, G. N. Kononykhin, A. N. Rogotovsky, A. A. Shipel’nikov, N. A. Bobyleva","doi":"10.3103/s0967091224700293","DOIUrl":"https://doi.org/10.3103/s0967091224700293","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Results of computational experiments on studying multiphase flow and interphase interaction in the volume of an industrial 50-ton tundish of a continuous caster, including when blowing with argon through bottom blowing blocks, are presented. A mathematical model has been developed that makes it possible to predict the dynamics of melt mixing at a given casting speed. The pattern of influence of the layout of the ladle’s working space on the area of “stagnant zones” in the ladle volume has been found.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222550","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 : 2024-09-09DOI: 10.3103/s0967091224700372
B. P. Yuryev, V. A. Dudko
Abstract
Large reserves of Baikal siderite ores require the development and implementation of methods for using them in metallurgical processing, both in pure form and in a mixture with other ores (for example, magnetite, brown iron ore). One of the methods of using a charge consisting of a mixture of siderite ore and brown iron ore in the production of a sinter is considered. In order to optimize the sintering process, the mechanism of the main reactions occurring in the sintering layer was studied. Knowing the thermal effects of these reactions, it is possible to determine the amount of heat required for the sintering process and obtain data on the consumption of solid fuel in the production of an agglomerate with the required properties. Results of studies using an experimental setup are presented. Influence of ore size, solid fuel consumption, layer height, and the ratio of siderite ore and brown iron ore contents in the charge was established. To obtain the necessary information with a minimum number of experiments performed, the method of planning experiments was used. The work results have a practical orientation, as they indicate the possibility of using siderite ores in metallurgical enterprises.
{"title":"Influence of Physical and Chemical Sintering Processes on the Quality of a Sinter","authors":"B. P. Yuryev, V. A. Dudko","doi":"10.3103/s0967091224700372","DOIUrl":"https://doi.org/10.3103/s0967091224700372","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Large reserves of Baikal siderite ores require the development and implementation of methods for using them in metallurgical processing, both in pure form and in a mixture with other ores (for example, magnetite, brown iron ore). One of the methods of using a charge consisting of a mixture of siderite ore and brown iron ore in the production of a sinter is considered. In order to optimize the sintering process, the mechanism of the main reactions occurring in the sintering layer was studied. Knowing the thermal effects of these reactions, it is possible to determine the amount of heat required for the sintering process and obtain data on the consumption of solid fuel in the production of an agglomerate with the required properties. Results of studies using an experimental setup are presented. Influence of ore size, solid fuel consumption, layer height, and the ratio of siderite ore and brown iron ore contents in the charge was established. To obtain the necessary information with a minimum number of experiments performed, the method of planning experiments was used. The work results have a practical orientation, as they indicate the possibility of using siderite ores in metallurgical enterprises.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222388","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 : 2024-09-09DOI: 10.3103/s0967091224700402
Ya. I. Kosmatskii, D. N. Lysov, E. N. Kondrat’ev
Abstract
The situation in the Russian pipe industry is considered. The works, in which the authors studied various periods of the existence of pipe industry, have been analyzed. The main problems and risks in this field are highlighted. The dynamics of changes in the stress points in the Russian pipe industry are reflected and the prospects are considered.
{"title":"Stress Points and Potential of Development of the Pipe Industry in the Russian Federation","authors":"Ya. I. Kosmatskii, D. N. Lysov, E. N. Kondrat’ev","doi":"10.3103/s0967091224700402","DOIUrl":"https://doi.org/10.3103/s0967091224700402","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The situation in the Russian pipe industry is considered. The works, in which the authors studied various periods of the existence of pipe industry, have been analyzed. The main problems and risks in this field are highlighted. The dynamics of changes in the stress points in the Russian pipe industry are reflected and the prospects are considered.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222389","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 : 2024-09-09DOI: 10.3103/s0967091224700359
S. V. Serikov
Abstract
Based on examples of experimental data on increasing the strength of metals through combined thermomechanical processing (MTP, TMP, NHTMP, HTMP, TMMP), an experimental computational method for identifying metals with respect to operational reliability is proposed. A material matrix of seven physically justified parameters, easy to determine, has been defined. Specific examples of the method’s efficiency for structural alloy steels are provided.
{"title":"Methods of Increasing the Strength of Metals and Their Impact on Operational Reliability","authors":"S. V. Serikov","doi":"10.3103/s0967091224700359","DOIUrl":"https://doi.org/10.3103/s0967091224700359","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Based on examples of experimental data on increasing the strength of metals through combined thermomechanical processing (MTP, TMP, NHTMP, HTMP, TMMP), an experimental computational method for identifying metals with respect to operational reliability is proposed. A material matrix of seven physically justified parameters, easy to determine, has been defined. Specific examples of the method’s efficiency for structural alloy steels are provided.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222385","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 : 2024-09-09DOI: 10.3103/s0967091224700414
R. R. Adigamov, V. A. Andreev, S. O. Rogachev, N. Yu. Tabachkova, E. S. Fedotov, V. S. Yusupov
Abstract
The results of a study of changes in the structure and mechanical properties of pipe steel during the production of high-strength profiles are presented. A simultaneous analysis of deformation diagrams and acoustic emission signals shows differences in the deformability and fracture kinetics of the original hot-rolled sheet samples and the base metal of the formed pipe. It is established that high amount of cold deformation during pipe processing cause an increase in the dislocation density by several orders of magnitude up to 1011 cm–2, as a result of which the metal reaches its hardening limit and loses its plasticity margin, which causes a sharp (2–3 times) decrease in relative elongation.
{"title":"Changes in the Properties of Pipe Steel during Cold Deformation in Production of High Strength Profile","authors":"R. R. Adigamov, V. A. Andreev, S. O. Rogachev, N. Yu. Tabachkova, E. S. Fedotov, V. S. Yusupov","doi":"10.3103/s0967091224700414","DOIUrl":"https://doi.org/10.3103/s0967091224700414","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of a study of changes in the structure and mechanical properties of pipe steel during the production of high-strength profiles are presented. A simultaneous analysis of deformation diagrams and acoustic emission signals shows differences in the deformability and fracture kinetics of the original hot-rolled sheet samples and the base metal of the formed pipe. It is established that high amount of cold deformation during pipe processing cause an increase in the dislocation density by several orders of magnitude up to 10<sup>11</sup> cm<sup>–2</sup>, as a result of which the metal reaches its hardening limit and loses its plasticity margin, which causes a sharp (2–3 times) decrease in relative elongation.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"97 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222391","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 : 2024-09-09DOI: 10.3103/s0967091224700426
B. N. Guzanov, O. S. Lekhov, D. Kh. Bilalov, A. V. Mikhalev
Abstract
In this paper, we describe the technology for producing three-layer steel sheets in one pass using a compact setup for a combined process of continuous casting and deformation. The results of a study of the structure and mechanical properties of the strip obtained using the considered setup when compacting a shell from a melt of 15ps steel on a base of 09G2S steel are presented. The microstructures of steel bimetal layers, including structures near the boundary of their joining, are shown. Microhardness measurement data and tensile test results are presented.
{"title":"Evaluation of a Combined Casting and Deformation Process in the Production of a Three-Layer Steel Strip","authors":"B. N. Guzanov, O. S. Lekhov, D. Kh. Bilalov, A. V. Mikhalev","doi":"10.3103/s0967091224700426","DOIUrl":"https://doi.org/10.3103/s0967091224700426","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In this paper, we describe the technology for producing three-layer steel sheets in one pass using a compact setup for a combined process of continuous casting and deformation. The results of a study of the structure and mechanical properties of the strip obtained using the considered setup when compacting a shell from a melt of 15ps steel on a base of 09G2S steel are presented. The microstructures of steel bimetal layers, including structures near the boundary of their joining, are shown. Microhardness measurement data and tensile test results are presented.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222397","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 : 2024-09-09DOI: 10.3103/s0967091224700384
S. V. Davydov, L. V. Spivak, N. E. Shchepina
Abstract
Iron polymorphism, as a basic phase transformation in the industrial technology of iron-carbon alloys, manifests itself in three forms in iron heating and cooling. An analysis of the literature data revealed a lack of information about the mechanism of pure iron polymorphic transformation. In this work, an experimental verification of the second polymorphic transformation α-Fe ↔ γ-Fe is carried out using high-resolution differential scanning calorimetry (DSC). The object of the study are samples made from wire of technically pure iron (TPI–99.88% Fe) and high-purity zone-purified iron (ZPI–99.995% Fe). Heating and cooling are carried out in an argon atmosphere (99.9995% Ar). Based on the analysis of DSC curves, the following results are obtained: the value of hysteresis of the polymorphic transformation during thermal cycling is ~11°C; the iron polymorphic transformation is not reversible upon heating and cooling and occurs through different mechanisms; existing ideas about the reversible polymorphic phase transformation of α-Fe ↔ γ-Fe upon heating as phase recrystallization within the framework of a deformation (distortion) transition are untenable. It is experimentally proven that the pure iron polymorphic transformation under equilibrium conditions upon heating proceeds diffusion-free with a sequential change of three phase transformations of different origins. Jump in atomic volumes of polymorph phases α-Fe ↔ γ-Fe in the region of phase transformation is explained by indirect shear plastic transformation of the α-Fe polymorph crystal lattice into the γ-Fe polymorph crystal lattice, as is customary to date, but by the sequential destructuring of the α-Fe polymorph into a mixture of “paracluster” and amorphous phases. Within the framework of these studies, the following unsolved problems are identified: firstly, the process during which a significant amount of activation energy G is absorbed, is unclear: for TPI 2300 ± 150 kJ/mol, for ZPI 2400 ± 200 kJ/mol; secondly, there is no explanation for the mechanism of the iron crystal lattice transition to the amorphous state when heated; thirdly, the temperature of the polymorphic transformation range in carbon steel 20 does not coincide with the similar temperature range on the Fe–C diagram.
{"title":"Calorimetric Studies of Polymorphic Iron Transformation","authors":"S. V. Davydov, L. V. Spivak, N. E. Shchepina","doi":"10.3103/s0967091224700384","DOIUrl":"https://doi.org/10.3103/s0967091224700384","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Iron polymorphism, as a basic phase transformation in the industrial technology of iron-carbon alloys, manifests itself in three forms in iron heating and cooling. An analysis of the literature data revealed a lack of information about the mechanism of pure iron polymorphic transformation. In this work, an experimental verification of the second polymorphic transformation α-Fe ↔ γ-Fe is carried out using high-resolution differential scanning calorimetry (DSC). The object of the study are samples made from wire of technically pure iron (TPI–99.88% Fe) and high-purity zone-purified iron (ZPI–99.995% Fe). Heating and cooling are carried out in an argon atmosphere (99.9995% Ar). Based on the analysis of DSC curves, the following results are obtained: the value of hysteresis of the polymorphic transformation during thermal cycling is ~11°C; the iron polymorphic transformation is not reversible upon heating and cooling and occurs through different mechanisms; existing ideas about the reversible polymorphic phase transformation of α-Fe ↔ γ-Fe upon heating as phase recrystallization within the framework of a deformation (distortion) transition are untenable. It is experimentally proven that the pure iron polymorphic transformation under equilibrium conditions upon heating proceeds diffusion-free with a sequential change of three phase transformations of different origins. Jump in atomic volumes of polymorph phases α-Fe ↔ γ-Fe in the region of phase transformation is explained by indirect shear plastic transformation of the α-Fe polymorph crystal lattice into the γ-Fe polymorph crystal lattice, as is customary to date, but by the sequential destructuring of the α-Fe polymorph into a mixture of “paracluster” and amorphous phases. Within the framework of these studies, the following unsolved problems are identified: firstly, the process during which a significant amount of activation energy <i>G</i> is absorbed, is unclear: for TPI 2300 ± 150 kJ/mol, for ZPI 2400 ± 200 kJ/mol; secondly, there is no explanation for the mechanism of the iron crystal lattice transition to the amorphous state when heated; thirdly, the temperature of the polymorphic transformation range in carbon steel 20 does not coincide with the similar temperature range on the Fe–C diagram.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222394","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 : 2024-09-09DOI: 10.3103/s0967091224700281
A. A. Odintsov, V. K. Nikolaev
Abstract
In this paper, we generalize the experience of using surfactants under laboratory and industrial conditions of the sintering process. The results of laboratory studies on the use of powdered polyacrylamide in agglomeration are presented. An analysis of the research results showed a positive effect of polyacrylamide on the performance of the sintering process and the quality of the sinter, which is associated with the formation of a more optimal granulometric composition of the pelletized charge and an increase in the temperature-thermal level of the sintering process. Based on the obtained laboratory data, recommendations for conducting industrial tests are formulated.
{"title":"Use of Polyacrylamide as an Additional Intensifier of the Sintering Process","authors":"A. A. Odintsov, V. K. Nikolaev","doi":"10.3103/s0967091224700281","DOIUrl":"https://doi.org/10.3103/s0967091224700281","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In this paper, we generalize the experience of using surfactants under laboratory and industrial conditions of the sintering process. The results of laboratory studies on the use of powdered polyacrylamide in agglomeration are presented. An analysis of the research results showed a positive effect of polyacrylamide on the performance of the sintering process and the quality of the sinter, which is associated with the formation of a more optimal granulometric composition of the pelletized charge and an increase in the temperature-thermal level of the sintering process. Based on the obtained laboratory data, recommendations for conducting industrial tests are formulated.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222547","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 : 2024-09-09DOI: 10.3103/s096709122470030x
V. Yu. Stetsenko, A. V. Stetsenko
Abstract
Dissolved hydrogen acts as a demodifying element in the formation of aluminum oxide microcrystals in liquid steels. Hydrogen atoms in liquid steels serve as surface-active elements for aluminum oxide microcrystals. Modifiers significantly reduce the hydrogen concentration in steel melts. This enhances the process of coagulation of aluminum oxide microcrystals into large particles that quickly float in liquid steels. To more effectively remove aluminum oxide particles from them, the casting process should not begin immediately after treating steel melts with modifiers.
{"title":"Crystallization of Aluminum Oxide in Liquid Steels","authors":"V. Yu. Stetsenko, A. V. Stetsenko","doi":"10.3103/s096709122470030x","DOIUrl":"https://doi.org/10.3103/s096709122470030x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Dissolved hydrogen acts as a demodifying element in the formation of aluminum oxide microcrystals in liquid steels. Hydrogen atoms in liquid steels serve as surface-active elements for aluminum oxide microcrystals. Modifiers significantly reduce the hydrogen concentration in steel melts. This enhances the process of coagulation of aluminum oxide microcrystals into large particles that quickly float in liquid steels. To more effectively remove aluminum oxide particles from them, the casting process should not begin immediately after treating steel melts with modifiers.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222548","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 : 2024-09-09DOI: 10.3103/s0967091224700335
K. N. Solomonov, L. I. Tischuk, S. M. Gorbatyuk, O. N. Chicheneva, A. A. Gerasimova
Abstract
Computer simulation of the metal flow pattern during the settlement of flat billets is considered on the basis of the developed “equi-theory” based on the principle of the shortest normal, which makes it possible to build a drawing of a multi-contour billet according to the specified dimensions, to determine the metal flow separating lines, streamlines, to analyze the metal flow pattern, and to substantiate the use of technological methods and structural elements that prevent or reduce the risk of defects. The general characteristics of broadly oriented, special and highly specialized software complexes are presented, their advantages and weaknesses are noted. The results of computer modeling of the metal flow pattern for complex multi-contour workpieces using the developed EQUI software package are shown.
{"title":"Application of Сomputer Modeling for the Analysis of the Flow of Metal during the Settlement of Flat Billets","authors":"K. N. Solomonov, L. I. Tischuk, S. M. Gorbatyuk, O. N. Chicheneva, A. A. Gerasimova","doi":"10.3103/s0967091224700335","DOIUrl":"https://doi.org/10.3103/s0967091224700335","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Computer simulation of the metal flow pattern during the settlement of flat billets is considered on the basis of the developed “equi-theory” based on the principle of the shortest normal, which makes it possible to build a drawing of a multi-contour billet according to the specified dimensions, to determine the metal flow separating lines, streamlines, to analyze the metal flow pattern, and to substantiate the use of technological methods and structural elements that prevent or reduce the risk of defects. The general characteristics of broadly oriented, special and highly specialized software complexes are presented, their advantages and weaknesses are noted. The results of computer modeling of the metal flow pattern for complex multi-contour workpieces using the developed EQUI software package are shown.</p>","PeriodicalId":21903,"journal":{"name":"Steel in Translation","volume":"108 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222551","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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