Pub Date : 2024-06-04DOI: 10.37394/232012.2024.19.6
Nikolai I. Kobasko
In the paper high temperature and low temperature intensive thermomechanical treatment is discussed. It is based on recently discovered new three physical principles that belong to the transient nucleate boiling process taking place in cold fluids. Such processes are considered in conditions when any film boiling during quenching in cold fluids is completely absent. That makes nucleate boiling very intensive, i.e. . The discoveries are used for direct quenching articles after forgings. The first is intensive high-temperature thermo-mechanical treatment (HTTMT). It is used for low and middle-carbon alloy steels. Forged steel parts are intensively quenched with a cooling interruption at the proper time to form surface compression residual stresses and fine bainitic microstructure at the core that increases radically surface life of forgings. The second method includes high-temperature and low temperature intensive thermo - mechanical treatment (LTTMT) of high carbon alloy steels with delaying martensitic transformation to make low-temperature thermo - mechanical treatment (LTTMT) possible. Then, after high temperature and low-temperature thermomechanical treatment, the steel goes to immediate tempering to create highly strengthened fine bainitic microstructure throughout the section of the steel part. A modified method of cooling time calculation, suitable for any size and form of steel part, is widely discussed in this paper.
{"title":"Transient Nucleate Boiling and Its Use for Thermomechanical Technologies Development","authors":"Nikolai I. Kobasko","doi":"10.37394/232012.2024.19.6","DOIUrl":"https://doi.org/10.37394/232012.2024.19.6","url":null,"abstract":"In the paper high temperature and low temperature intensive thermomechanical treatment is discussed. It is based on recently discovered new three physical principles that belong to the transient nucleate boiling process taking place in cold fluids. Such processes are considered in conditions when any film boiling during quenching in cold fluids is completely absent. That makes nucleate boiling very intensive, i.e. . The discoveries are used for direct quenching articles after forgings. The first is intensive high-temperature thermo-mechanical treatment (HTTMT). It is used for low and middle-carbon alloy steels. Forged steel parts are intensively quenched with a cooling interruption at the proper time to form surface compression residual stresses and fine bainitic microstructure at the core that increases radically surface life of forgings. The second method includes high-temperature and low temperature intensive thermo - mechanical treatment (LTTMT) of high carbon alloy steels with delaying martensitic transformation to make low-temperature thermo - mechanical treatment (LTTMT) possible. Then, after high temperature and low-temperature thermomechanical treatment, the steel goes to immediate tempering to create highly strengthened fine bainitic microstructure throughout the section of the steel part. A modified method of cooling time calculation, suitable for any size and form of steel part, is widely discussed in this paper.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"26 4-5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141266530","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 : 2024-04-22DOI: 10.37394/232012.2024.19.5
A. El Harfouf, Rachid Herbazi, Walid Abouloifa, S. Mounir, H. Mes-Adi, A. Wakif, M. Mejdal, M. Nfaoui
One of the main areas of study in the field is increasingly the flow of non-Newtonian fluids. These liquids find extensive use in nuclear reactors, food processing, paint and adhesives, drilling rigs, and cooling systems, among other industrial and engineering domains. However, hybrid nanofluids are crucial to the process of heat transfer. Considering this, this study investigates the motion of a Casson hybrid nanofluid squeezing flow between two parallel plates under the influence of a heat source and thermophoretic particle deposition. The Runge–Kutta–Fehlberg fourth–fifth-order approach is utilized to numerically solve the ordinary differential equations derived from the partial differential equations governing fluid flow, by utilizing suitable similarity variables. The diagrams show how several important parameters affect fluid profiles both with and without the Casson parameter. These figures demonstrate how fluid velocity increases as the local porosity parameter increases. When the heat source/sink parameter is increased, thermal dispersal increases, and when the thermophoretic parameter is increased, the concentration profile increases.
{"title":"Numerical Examination of a Squeezing Casson Hybrid Nanofluid Flow Considering Thermophoretic and Internal Heating Mechanisms","authors":"A. El Harfouf, Rachid Herbazi, Walid Abouloifa, S. Mounir, H. Mes-Adi, A. Wakif, M. Mejdal, M. Nfaoui","doi":"10.37394/232012.2024.19.5","DOIUrl":"https://doi.org/10.37394/232012.2024.19.5","url":null,"abstract":"One of the main areas of study in the field is increasingly the flow of non-Newtonian fluids. These liquids find extensive use in nuclear reactors, food processing, paint and adhesives, drilling rigs, and cooling systems, among other industrial and engineering domains. However, hybrid nanofluids are crucial to the process of heat transfer. Considering this, this study investigates the motion of a Casson hybrid nanofluid squeezing flow between two parallel plates under the influence of a heat source and thermophoretic particle deposition. The Runge–Kutta–Fehlberg fourth–fifth-order approach is utilized to numerically solve the ordinary differential equations derived from the partial differential equations governing fluid flow, by utilizing suitable similarity variables. The diagrams show how several important parameters affect fluid profiles both with and without the Casson parameter. These figures demonstrate how fluid velocity increases as the local porosity parameter increases. When the heat source/sink parameter is increased, thermal dispersal increases, and when the thermophoretic parameter is increased, the concentration profile increases.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"79 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140675152","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 : 2024-04-01DOI: 10.37394/232012.2024.19.4
Meryem Brahimi, R. Benderradji, H. Gouidmi
This research presents the results of a numerical study on mixed convection in a ventilated cavity with a central cold block of varying shapes. The direction of the forced flow of Ag/water nanofluid is perpendicular to the transverse axis (y) of the central cold block. Mixed convection is induced by cooling at the entrance of the ventilated cavity and uniformly heating its bottom wall. The governing equations for the flow of an incompressible Newtonian nanofluid are assumed to be two-dimensional, steady, and laminar. The finite volume method is employed for numerical simulations. A series of calculations are conducted to investigate the effects of key influencing factors: Reynolds number (Re = 100), Richardson number (Ri = 1), and nanoparticle volume fractions (0 ≤ ∅ ≤ 8%) on the enhancement of heat transfer. The impact of four different geometric shapes of the cold obstacle (circular, square, triangular, and elliptical) on fluid flow and heat transfer rate is also explored. The results indicate that an increase in nanoparticle volume fraction enhances the heat exchange rate in the cavity only when the geometric shape of the cold obstacle is circular. This is followed by square and triangular shapes, which approximately yield concordant results, and then the elliptical shape.
{"title":"Mixed Convection of an Ag/Water Nanofluid in a Ventilated Square Cavity Containing Cold Blocks of Different Shapes","authors":"Meryem Brahimi, R. Benderradji, H. Gouidmi","doi":"10.37394/232012.2024.19.4","DOIUrl":"https://doi.org/10.37394/232012.2024.19.4","url":null,"abstract":"This research presents the results of a numerical study on mixed convection in a ventilated cavity with a central cold block of varying shapes. The direction of the forced flow of Ag/water nanofluid is perpendicular to the transverse axis (y) of the central cold block. Mixed convection is induced by cooling at the entrance of the ventilated cavity and uniformly heating its bottom wall. The governing equations for the flow of an incompressible Newtonian nanofluid are assumed to be two-dimensional, steady, and laminar. The finite volume method is employed for numerical simulations. A series of calculations are conducted to investigate the effects of key influencing factors: Reynolds number (Re = 100), Richardson number (Ri = 1), and nanoparticle volume fractions (0 ≤ ∅ ≤ 8%) on the enhancement of heat transfer. The impact of four different geometric shapes of the cold obstacle (circular, square, triangular, and elliptical) on fluid flow and heat transfer rate is also explored. The results indicate that an increase in nanoparticle volume fraction enhances the heat exchange rate in the cavity only when the geometric shape of the cold obstacle is circular. This is followed by square and triangular shapes, which approximately yield concordant results, and then the elliptical shape.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"24 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140762992","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 : 2024-03-28DOI: 10.37394/232012.2024.19.2
N. Kobasko
In the paper, the new intensive quenching technologies are discussed which are based on controlling the self-regulated thermal process (SRTP) which exists for a long time if any film boiling is absent. It is rather intensive until convection starts. Despite the intense process (Kn > 0.8), when the heat transfer coefficient and Biot number tend to infinity, there are several ways of controlling the surface temperature of steel components by varying the boiling temperature of the fluid. To eliminate any film boiling process and provide SRTP, the author of the paper explores the resonance effect, a thin surface insulating layer that covers the surface of machine components and electrical negative forces to control the double electrical layer that is responsible for destroying the film boiling mode. Based on SRTP control it is possible to delay the transformation austenite into martensite or even accelerate these transformations. The most important are possibilities to control surface temperature during the boiling process. All of this opens great opportunities for increasing significantly service life of machine components and tools. In the paper also the simplified method of cooling time calculation is proposed. It is based on the new principles concerning pure transient nucleate boiling taking place during the hardening steel in cold fluids. Since the paper simply explains everything, results of investigations will be widely used in the heat-treating industry.
{"title":"Contemporary Intensive Methods of Steel Hardening in Cold Fluids","authors":"N. Kobasko","doi":"10.37394/232012.2024.19.2","DOIUrl":"https://doi.org/10.37394/232012.2024.19.2","url":null,"abstract":"In the paper, the new intensive quenching technologies are discussed which are based on controlling the self-regulated thermal process (SRTP) which exists for a long time if any film boiling is absent. It is rather intensive until convection starts. Despite the intense process (Kn > 0.8), when the heat transfer coefficient and Biot number tend to infinity, there are several ways of controlling the surface temperature of steel components by varying the boiling temperature of the fluid. To eliminate any film boiling process and provide SRTP, the author of the paper explores the resonance effect, a thin surface insulating layer that covers the surface of machine components and electrical negative forces to control the double electrical layer that is responsible for destroying the film boiling mode. Based on SRTP control it is possible to delay the transformation austenite into martensite or even accelerate these transformations. The most important are possibilities to control surface temperature during the boiling process. All of this opens great opportunities for increasing significantly service life of machine components and tools. In the paper also the simplified method of cooling time calculation is proposed. It is based on the new principles concerning pure transient nucleate boiling taking place during the hardening steel in cold fluids. Since the paper simply explains everything, results of investigations will be widely used in the heat-treating industry.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"49 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140373364","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 : 2024-01-26DOI: 10.37394/232012.2024.19.1
Chaima Bouraoui, F. B. Nejma
Understanding radiative exchange in a porous medium is a crucial step that can provide significant insights and improvements in its characteristics, enhancing its practical utility across various industrial applications. In this paper, a numerical model, utilizing the finite element method (FEM), was developed to predict the radiative transfer between a diffusely/specularly reflecting cylindrical packed bed porous medium and a plane heating surface. Four different structures of the medium were suggested to examine the effect of the particles ‘disposition on the radiative properties of the medium. The assessment of normalized flux distribution enables the computation of effective radiative properties including reflectivity, transmissivity, and absorptivity for particles exhibiting diffuse and specular reflection. The results underscore the significant influence of particle arrangement on media properties. The structure of the second model allowed for the attainment of an opaque surface from the first layer. Meaningful correlations can be established from the presented curves, offering a streamlined and accurate method for determining effective radiative property coefficients based on emissivity in future model applications.
{"title":"Identification of the Effective Radiative Properties of Cylindrical Packed Bed Porous Media","authors":"Chaima Bouraoui, F. B. Nejma","doi":"10.37394/232012.2024.19.1","DOIUrl":"https://doi.org/10.37394/232012.2024.19.1","url":null,"abstract":"Understanding radiative exchange in a porous medium is a crucial step that can provide significant insights and improvements in its characteristics, enhancing its practical utility across various industrial applications. In this paper, a numerical model, utilizing the finite element method (FEM), was developed to predict the radiative transfer between a diffusely/specularly reflecting cylindrical packed bed porous medium and a plane heating surface. Four different structures of the medium were suggested to examine the effect of the particles ‘disposition on the radiative properties of the medium. The assessment of normalized flux distribution enables the computation of effective radiative properties including reflectivity, transmissivity, and absorptivity for particles exhibiting diffuse and specular reflection. The results underscore the significant influence of particle arrangement on media properties. The structure of the second model allowed for the attainment of an opaque surface from the first layer. Meaningful correlations can be established from the presented curves, offering a streamlined and accurate method for determining effective radiative property coefficients based on emissivity in future model applications.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"42 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139594009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-20DOI: 10.37394/232012.2023.18.11
D. Sponza, Ruki̇ye Özteki̇n
In this study, heat and mass limitations in an anaerobic reactor containing domestic solids were researched in batch reactors. The dynamic and static anaerobic data for 365 days showed that the methane production for the dynamic digestion reactor was measured as 176.86 m3 which is extremely high for static anaerobic one (102.78 m3). As the heat transfer data increased with elevated temperature the methane productions also were highlighted. The external mass transfer was observed for easily degradable solids. In the calculation of external mass transfer during the degradation of organics dissolved with difficulty some semiempirical regressions were used. In the calculation of internal mass transfer the microorganisms in the solids were taken into consideration and the diffusion was defined with Fick's law. The diffusion coefficient D, was found to be constant. Generally, the diffusion coefficient of solids in water (Dw) was < 1.0. The effect of the total solid (TS) concentration in anaerobic batch reactors (TS between 12% and 39%) was investigated. The methane gas production decreased minorly when the TS levels elevated to 30%. At a TS percentage of 39%, the methane generation decreased significantly. At high TS, the mass transfer was inhibited and ended with lowered methane generations while the hydrolysis process did not affect significantly at high TS concentrations.
{"title":"Heat and Mass Limitations in an Anaerobic Digestion Process","authors":"D. Sponza, Ruki̇ye Özteki̇n","doi":"10.37394/232012.2023.18.11","DOIUrl":"https://doi.org/10.37394/232012.2023.18.11","url":null,"abstract":"In this study, heat and mass limitations in an anaerobic reactor containing domestic solids were researched in batch reactors. The dynamic and static anaerobic data for 365 days showed that the methane production for the dynamic digestion reactor was measured as 176.86 m3 which is extremely high for static anaerobic one (102.78 m3). As the heat transfer data increased with elevated temperature the methane productions also were highlighted. The external mass transfer was observed for easily degradable solids. In the calculation of external mass transfer during the degradation of organics dissolved with difficulty some semiempirical regressions were used. In the calculation of internal mass transfer the microorganisms in the solids were taken into consideration and the diffusion was defined with Fick's law. The diffusion coefficient D, was found to be constant. Generally, the diffusion coefficient of solids in water (Dw) was < 1.0. The effect of the total solid (TS) concentration in anaerobic batch reactors (TS between 12% and 39%) was investigated. The methane gas production decreased minorly when the TS levels elevated to 30%. At a TS percentage of 39%, the methane generation decreased significantly. At high TS, the mass transfer was inhibited and ended with lowered methane generations while the hydrolysis process did not affect significantly at high TS concentrations.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"88 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138954247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-05DOI: 10.37394/232012.2023.18.8
Benali Abdelhakim
This article presents a study and simulation of the desalination system consisting of a heat pump HP and a multi-effect distillation MED unit. Electric energy using in HP is provided by photovoltaic panels and wind turbines ,for a possible installation of the system on an isolated sites.The proposed desalination system uses an additional source of thermal energy in order to make HP and MED integration optimal and to reduce HP Electrical energy consumption per cubic meter of distilled water (kwh/m3).The main idea is to use geothermal-solar thermal energy and heat from HP as two thermal inputs in the multi-effect distillation unit MED. Thermal rejection from MED is recovered to be used as heat input in HP that based on mechanical compression of working fluid. The HP can use the working fluids (R22, ammonia) for a number of reasons, including that the two previous fluids are very dense at the saturated vapor state compared to water. A thermodynamic analysis of the desalination system was performed at steady state, using the thermodynamic properties of the Coolprop database. The simulation results showed a minimum value of electrical energy consumption, without consideration the contribution of auxiliary thermal energy :(10.487 kwh/m3 | effect numbre:5).The simulation results showed a minimum value of volumetric flow rate of the working fluid ,before compression : (17.685 m3 of working fluid per m3 of distilled water | effect numbre:12 | contribution ratio of auxiliary thermal energy:46.6 %).
{"title":"Multi-effect Distillation with Heat Pump Integrated","authors":"Benali Abdelhakim","doi":"10.37394/232012.2023.18.8","DOIUrl":"https://doi.org/10.37394/232012.2023.18.8","url":null,"abstract":"This article presents a study and simulation of the desalination system consisting of a heat pump HP and a multi-effect distillation MED unit. Electric energy using in HP is provided by photovoltaic panels and wind turbines ,for a possible installation of the system on an isolated sites.The proposed desalination system uses an additional source of thermal energy in order to make HP and MED integration optimal and to reduce HP Electrical energy consumption per cubic meter of distilled water (kwh/m3).The main idea is to use geothermal-solar thermal energy and heat from HP as two thermal inputs in the multi-effect distillation unit MED. Thermal rejection from MED is recovered to be used as heat input in HP that based on mechanical compression of working fluid. The HP can use the working fluids (R22, ammonia) for a number of reasons, including that the two previous fluids are very dense at the saturated vapor state compared to water. A thermodynamic analysis of the desalination system was performed at steady state, using the thermodynamic properties of the Coolprop database. The simulation results showed a minimum value of electrical energy consumption, without consideration the contribution of auxiliary thermal energy :(10.487 kwh/m3 | effect numbre:5).The simulation results showed a minimum value of volumetric flow rate of the working fluid ,before compression : (17.685 m3 of working fluid per m3 of distilled water | effect numbre:12 | contribution ratio of auxiliary thermal energy:46.6 %).","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135481010","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 examines the mechanism for researching and improving the energy efficiency of a solar water heating system (SWH) in a building located in Kazakhstan. In this paper, we use data collected from LoRaWAN to obtain information about various environmental and operational aspects of the system under consideration, which determine the possibilities for improving the efficiency of various SWH subsystems and develop management strategies for the effective operation of the entire system. With the help of data collected by IoT, such as water consumption, the schedule of the heat pump and water pump, the availability of solar energy and electricity consumption, we conduct a comprehensive energy audit to analyze the efficiency of subsystems, as well as the performance of the system as a whole. Based on the findings obtained from the data analysis, appropriate management strategies are developed for various subsystems in order to increase the efficiency of the entire system and reduce the operating costs of SWH.
{"title":"Development and Research of a Two-Contour Solar System in the Lorawan Network","authors":"Kunelbayev Murat, Imankulova Binara, Sundetov Talgat, Tyulepberdinova Gulnur, Issabayeva Sulu, Sagimbayev Lida","doi":"10.37394/232012.2023.18.5","DOIUrl":"https://doi.org/10.37394/232012.2023.18.5","url":null,"abstract":"This article examines the mechanism for researching and improving the energy efficiency of a solar water heating system (SWH) in a building located in Kazakhstan. In this paper, we use data collected from LoRaWAN to obtain information about various environmental and operational aspects of the system under consideration, which determine the possibilities for improving the efficiency of various SWH subsystems and develop management strategies for the effective operation of the entire system. With the help of data collected by IoT, such as water consumption, the schedule of the heat pump and water pump, the availability of solar energy and electricity consumption, we conduct a comprehensive energy audit to analyze the efficiency of subsystems, as well as the performance of the system as a whole. Based on the findings obtained from the data analysis, appropriate management strategies are developed for various subsystems in order to increase the efficiency of the entire system and reduce the operating costs of SWH.","PeriodicalId":477337,"journal":{"name":"WSEAS transactions on heat and mass transfer","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136000769","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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