Marta Maksymovych, Aleksandr Lazorko, O. Maksymovych, O. Dmitriiev
In this article effective approach of the study of high-stress concentration at closely placed holes in wing bearing area (in anisotropic plates) is proposed. It is based on the boundary integral equation method with the additional use of the asymptotic method. The simplicity, precision of the approach and the stability of the solution are illustrated in the calculation of stresses in the plate with a circular hole, an elliptical hole, elongated holes, a plate with two closely spaced elliptical holes
{"title":"Research of stress concentration at closely placed holes in wing bearing area in anisotropic plates","authors":"Marta Maksymovych, Aleksandr Lazorko, O. Maksymovych, O. Dmitriiev","doi":"10.29354/diag/155259","DOIUrl":"https://doi.org/10.29354/diag/155259","url":null,"abstract":"In this article effective approach of the study of high-stress concentration at closely placed holes in wing bearing area (in anisotropic plates) is proposed. It is based on the boundary integral equation method with the additional use of the asymptotic method. The simplicity, precision of the approach and the stability of the solution are illustrated in the calculation of stresses in the plate with a circular hole, an elliptical hole, elongated holes, a plate with two closely spaced elliptical holes","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48966034","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 paper is to present an experimental study of the impact of surface hardening on the high-cycle fatigue behavior of an isotropic beam. The beams made from low carbon steel (St 44-2). Surface treatments used are pack carburizing and carbonitriding. The experimental work included mechanical test, surface heat treatment, fatigue test and Microscopic inspection. The surface hardening was done by using pack-carburizing process at a temperature of 925°C holding time variation (2, 4, and 6hr) followed by quenching and tempering process, and using the carbonitriding process at a temperature of 800°C and for periods (0.5, 1 and 1.5hr) then quenching directly in water. The fatigue test was carried out by a cantilever rotating-bending system. The results of an experimental fatigue test indicate that various behaviors depend on surface heat treatment and time soaking. The findings indicate that carbonitriding has a greater impact on the fatigue strength and life than the specimen has been treated with pack carburizing. In addition, as the time soaking increase, the fatigue life will increase for both types of surface heat treatments. It was found that the specimens that were hardened using the carbonitriding process achieved a higher surface hardness as the hardness increased to 1644.62HV, while the untreated specimens were 293HV. Compared with the hardening using the pack carburizing
{"title":"Surface hardening effect on the fatigue behavior of isotropic beam","authors":"Sajjad H, Nasser, Qasim H. Bader","doi":"10.29354/diag/154901","DOIUrl":"https://doi.org/10.29354/diag/154901","url":null,"abstract":"This paper is to present an experimental study of the impact of surface hardening on the high-cycle fatigue behavior of an isotropic beam. The beams made from low carbon steel (St 44-2). Surface treatments used are pack carburizing and carbonitriding. The experimental work included mechanical test, surface heat treatment, fatigue test and Microscopic inspection. The surface hardening was done by using pack-carburizing process at a temperature of 925°C holding time variation (2, 4, and 6hr) followed by quenching and tempering process, and using the carbonitriding process at a temperature of 800°C and for periods (0.5, 1 and 1.5hr) then quenching directly in water. The fatigue test was carried out by a cantilever rotating-bending system. The results of an experimental fatigue test indicate that various behaviors depend on surface heat treatment and time soaking. The findings indicate that carbonitriding has a greater impact on the fatigue strength and life than the specimen has been treated with pack carburizing. In addition, as the time soaking increase, the fatigue life will increase for both types of surface heat treatments. It was found that the specimens that were hardened using the carbonitriding process achieved a higher surface hardness as the hardness increased to 1644.62HV, while the untreated specimens were 293HV. Compared with the hardening using the pack carburizing","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45451400","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}
O. Voznyak, N. Spodyniuk, O. Savchenko, O. Dovbush, M. Kasynets, O. Datsko
The article is devoted to solving the significant problem of efficiency increasing of air distribution in the premise by swirl air jet. The aim of the article is to decrease coefficient of velocity attenuation due to intensification of initial turbulence of different air streams leakage from the air distributor and to obtain of analytical equations for calculation of air distribution in a room to ensure the normative indoor air parameters. Effect of flow twisting results in a reduction of the velocity attenuation coefficient by 2.4 times. The regression analysis testified that the attenuation coefficient of the swirl air jet is more affected by the angle of the twisting plates inclination and less affected by the angle of change of the air flow direction. The attenuation coefficient of all types of rectangular air jets is more influenced by the the ratio of the sides of slit b/l and the angle of change of the air flow direction is also less affected. To minimize the attenuation factor, it is effective to use air distributors at smaller swivel plates inclination angles for swirl air jets and a smaller slit size ratio for all types of rectangular air jets. α – angle of swivel plate’s inclination; β – angle the air b – height of the slit, m;
{"title":"Analysis of air jets velocity attenuation at special initial conditions","authors":"O. Voznyak, N. Spodyniuk, O. Savchenko, O. Dovbush, M. Kasynets, O. Datsko","doi":"10.29354/diag/154859","DOIUrl":"https://doi.org/10.29354/diag/154859","url":null,"abstract":"The article is devoted to solving the significant problem of efficiency increasing of air distribution in the premise by swirl air jet. The aim of the article is to decrease coefficient of velocity attenuation due to intensification of initial turbulence of different air streams leakage from the air distributor and to obtain of analytical equations for calculation of air distribution in a room to ensure the normative indoor air parameters. Effect of flow twisting results in a reduction of the velocity attenuation coefficient by 2.4 times. The regression analysis testified that the attenuation coefficient of the swirl air jet is more affected by the angle of the twisting plates inclination and less affected by the angle of change of the air flow direction. The attenuation coefficient of all types of rectangular air jets is more influenced by the the ratio of the sides of slit b/l and the angle of change of the air flow direction is also less affected. To minimize the attenuation factor, it is effective to use air distributors at smaller swivel plates inclination angles for swirl air jets and a smaller slit size ratio for all types of rectangular air jets. α – angle of swivel plate’s inclination; β – angle the air b – height of the slit, m;","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45427926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reliability of the mechanical properties of any product plays an important role in the longevity of the product to work properly under various working conditions. In the present study, the effect of preparing brass alloy on its mechanical properties was experimentally studied. Samples of brass (60% Cu-40% Zn) were prepared by hot iso-stating pressing (HIP) sintering method and some main mechanical tests were performed on them included porosity, density, hardness and compression tests. Results of these tests were compared with corresponding tests on commercial brass alloys produced by casting in order to show the effect of the method of preparing on their mechanical properties. There was a significant improvement in the hardness and strength of the sintered alloy due to the increasing in density and decreasing in porosity comparing with the corresponding other casting's alloys. Results showed an improvement in the density values by 8.4% as a result of the significant reduction in the porosity values from 8.65% to about 0.43%. As a result, the strength of the alloys prepared by the heat pressing method has jumped to a value of 600MPa compared to the traditional castings that have a strength of 343MPa.
{"title":"Influence of HIP sintering technique on the reliability of the mechanical properties of brass-an experimental study.","authors":"S. Alnomani","doi":"10.29354/diag/154830","DOIUrl":"https://doi.org/10.29354/diag/154830","url":null,"abstract":"The reliability of the mechanical properties of any product plays an important role in the longevity of the product to work properly under various working conditions. In the present study, the effect of preparing brass alloy on its mechanical properties was experimentally studied. Samples of brass (60% Cu-40% Zn) were prepared by hot iso-stating pressing (HIP) sintering method and some main mechanical tests were performed on them included porosity, density, hardness and compression tests. Results of these tests were compared with corresponding tests on commercial brass alloys produced by casting in order to show the effect of the method of preparing on their mechanical properties. There was a significant improvement in the hardness and strength of the sintered alloy due to the increasing in density and decreasing in porosity comparing with the corresponding other casting's alloys. Results showed an improvement in the density values by 8.4% as a result of the significant reduction in the porosity values from 8.65% to about 0.43%. As a result, the strength of the alloys prepared by the heat pressing method has jumped to a value of 600MPa compared to the traditional castings that have a strength of 343MPa.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46766505","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 paper proposes training an artificial neural network (ANN) by a particle swarm optimization (PSO) technique to predict the flashover voltage of outdoor insulators. The analysis follows a series of real-world tests on high-voltage insulators to form a database for implementing artificial intelligence concepts. These tests are performed in various degrees of artificial contamination (distilled brine). Each contamination level shows the amount of contamination in milliliters per area of the isolator. The acquisition database provides values of flashover voltage corresponding to their electrical conductivity in each isolation zone and different degrees of artificial contamination. The results show that ANN trained by PSO can not only provide better prediction results, but also reduce the amount of computation efforts. It is also a more powerful model because: it does not get stuck in a local optimum. In addition, it also has the advantages of simple logic, simple implementation, and underlying intelligence. Compared to the results obtained by practical tests, the results obtained present that the PSO-ANN technique is very effective to predict flashover of high-voltage polluted insulators.
{"title":"Particle swarm optimization of a neural network model for predicting the flashover voltage on polluted cap and pin insulator","authors":"Belkebir Amel, Bourek Yacine, Benguesmia Hani","doi":"10.29354/diag/154051","DOIUrl":"https://doi.org/10.29354/diag/154051","url":null,"abstract":"This paper proposes training an artificial neural network (ANN) by a particle swarm optimization (PSO) technique to predict the flashover voltage of outdoor insulators. The analysis follows a series of real-world tests on high-voltage insulators to form a database for implementing artificial intelligence concepts. These tests are performed in various degrees of artificial contamination (distilled brine). Each contamination level shows the amount of contamination in milliliters per area of the isolator. The acquisition database provides values of flashover voltage corresponding to their electrical conductivity in each isolation zone and different degrees of artificial contamination. The results show that ANN trained by PSO can not only provide better prediction results, but also reduce the amount of computation efforts. It is also a more powerful model because: it does not get stuck in a local optimum. In addition, it also has the advantages of simple logic, simple implementation, and underlying intelligence. Compared to the results obtained by practical tests, the results obtained present that the PSO-ANN technique is very effective to predict flashover of high-voltage polluted insulators.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47022809","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}
Y. Savchenko, M. Mykhalevych, P. Droździel, V. Verbitskiy, R. Wrona
Pneumatic suspension is increasingly used in many cars. Control of a car body level is the main function of the pneumatic suspension. The experimental determination of the pneumatic spring characteristics suitable for the design and modeling of the car level control system is presented. The characteristics of the pneumatic spring are determined, that determine the quality of the control system. The effect of temperature changes inside the pneumatic spring is experimentally determined due to heat exchange on air pressure and vertical force during alignment of the car body. In addition, through modeling is evaluated by changing the level of the car body due to the impact of heat transfer. An original method of controlling the lifting and lowering of the vehicle body is proposed. The method is based on the energy balance and is the basis for reducing the number of strokes of the electropneumatic valve. The change in the level of the body due to the temperature effect is leveled due to the indirect consideration of this effect using the pressure sensor in the cylinder. of compressed air temperature.
{"title":"Accuracy and durability increasing of the body level control systems in the immobile state of the vehicle","authors":"Y. Savchenko, M. Mykhalevych, P. Droździel, V. Verbitskiy, R. Wrona","doi":"10.29354/diag/154793","DOIUrl":"https://doi.org/10.29354/diag/154793","url":null,"abstract":"Pneumatic suspension is increasingly used in many cars. Control of a car body level is the main function of the pneumatic suspension. The experimental determination of the pneumatic spring characteristics suitable for the design and modeling of the car level control system is presented. The characteristics of the pneumatic spring are determined, that determine the quality of the control system. The effect of temperature changes inside the pneumatic spring is experimentally determined due to heat exchange on air pressure and vertical force during alignment of the car body. In addition, through modeling is evaluated by changing the level of the car body due to the impact of heat transfer. An original method of controlling the lifting and lowering of the vehicle body is proposed. The method is based on the energy balance and is the basis for reducing the number of strokes of the electropneumatic valve. The change in the level of the body due to the temperature effect is leveled due to the indirect consideration of this effect using the pressure sensor in the cylinder. of compressed air temperature.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44369312","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}
A. Bouboulas, P. Nikolakopoulos, Nikolaos Anifantis
The aim of this paper is to develop a finite element procedure for crack prediction in vibrating beams. Based on this procedure, full frictional contact conditions are introduced between the crack surfaces in order to consider the breathing of crack. The region surrounding the crack is simulated by two-dimensional finite elements. An incremental-iterative procedure is employed to solve the nonlinear dynamic equations governing this problem. The obtained time response is processed with Fast Fourier Transform to extract its frequency components. The first three natural frequencies are input to a trained Artificial Neural Network for depth and position prediction of the crack. This study is validated for a dynamic loading cantilever beam. It is found that the proposed procedure is capable of predicting the crack depth and position with high accuracy.
{"title":"Prediction of crack depth and position in vibrating beams using artificial neural networks","authors":"A. Bouboulas, P. Nikolakopoulos, Nikolaos Anifantis","doi":"10.29354/diag/154758","DOIUrl":"https://doi.org/10.29354/diag/154758","url":null,"abstract":"The aim of this paper is to develop a finite element procedure for crack prediction in vibrating beams. Based on this procedure, full frictional contact conditions are introduced between the crack surfaces in order to consider the breathing of crack. The region surrounding the crack is simulated by two-dimensional finite elements. An incremental-iterative procedure is employed to solve the nonlinear dynamic equations governing this problem. The obtained time response is processed with Fast Fourier Transform to extract its frequency components. The first three natural frequencies are input to a trained Artificial Neural Network for depth and position prediction of the crack. This study is validated for a dynamic loading cantilever beam. It is found that the proposed procedure is capable of predicting the crack depth and position with high accuracy.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45440015","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}
With the advancement of technology and the implementation of contemporary techniques and system controls, conventional methods of on-site monitoring have been replaced by remote supervision, which offers a number of advantages. As a result, it appears that a suitable strategy utilizing these contemporary approaches and incorporating information technology into the industry is required. The author's goal in this work is to describe a device for remotely transferring cathodic protection information from oil and gas pipelines to a platform server through the internet and sending alerts by SMS and e-mail. This system was developed and tested in Iraq's Al-Ahdab oil field. The system provides real-time, 24/7 assessment data with an accuracy of 99.7%.
{"title":"Remote monitoring of oil pipelines' cathodic protection system via GSM/GPRS modem and the thingspeak platform","authors":"A. Al-Attabi, Manaf K. Hussein","doi":"10.29354/diag/152481","DOIUrl":"https://doi.org/10.29354/diag/152481","url":null,"abstract":"With the advancement of technology and the implementation of contemporary techniques and system controls, conventional methods of on-site monitoring have been replaced by remote supervision, which offers a number of advantages. As a result, it appears that a suitable strategy utilizing these contemporary approaches and incorporating information technology into the industry is required. The author's goal in this work is to describe a device for remotely transferring cathodic protection information from oil and gas pipelines to a platform server through the internet and sending alerts by SMS and e-mail. This system was developed and tested in Iraq's Al-Ahdab oil field. The system provides real-time, 24/7 assessment data with an accuracy of 99.7%.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48196529","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 paper explores the role of the computational fluid dynamics (CFD) modeling technique in the design, regulation, and production of the gasoline direct injection (GDI) engine combustion system through literature reviews. It begins with a brief analysis of injector technologies and the effect of spray characteristics on the optimization of the combustion system. The key challenges of optimizing a homogeneous-charge GDI combustion system are the enhancement of volumetric performance and homogeneity of fuel-air mixing with reduced wetting of surface fuel and the improvement of power output. Most of the calculations focused on dynamic mesh strategy to manage moving geometry varied from case to case. The techniques of the methods varied. During the opening event of a GDI gasoline-injector for automotive applications, the findings of the literature indicate the primary fuel atomization.
{"title":"A review of the design and control using computational fluid dynamics of gasoline direct injection engines","authors":"Barhm Mohamad, Mohammed Ali","doi":"10.29354/diag/153373","DOIUrl":"https://doi.org/10.29354/diag/153373","url":null,"abstract":"This paper explores the role of the computational fluid dynamics (CFD) modeling technique in the design, regulation, and production of the gasoline direct injection (GDI) engine combustion system through literature reviews. It begins with a brief analysis of injector technologies and the effect of spray characteristics on the optimization of the combustion system. The key challenges of optimizing a homogeneous-charge GDI combustion system are the enhancement of volumetric performance and homogeneity of fuel-air mixing with reduced wetting of surface fuel and the improvement of power output. Most of the calculations focused on dynamic mesh strategy to manage moving geometry varied from case to case. The techniques of the methods varied. During the opening event of a GDI gasoline-injector for automotive applications, the findings of the literature indicate the primary fuel atomization.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47098503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The work of solar cells and their production of electrical energy have been affected by climate change, especially in hot regions which became significantly hotter and still receive relatively high levels of solar radiation throughout the year. Higher ambient temperature and solar radiation result in higher PV cell temperature and, therefore, the reduction in PV module power output and efficiency. This study investigates how a PV module performs throughout the year in a hot region by considering the variations in cell temperature resulting from changes in ambient temperature and solar radiation every day. The tilt angles and two-axis tracking have also been examined. Results indicate that the two-axis solar tracking system is critical to use in hot regions for obtaining higher output power. Therefore, part of this power can be used to cool solar panels using various methods to keep their efficiency high, such as operating air fans or operating pumps to cool them with coolant.
{"title":"The effects of climate change on photovoltaic solar production in hot regions","authors":"M. Al-Baghdadi, A. Ridha, A. Al-Khayyat","doi":"10.29354/diag/152276","DOIUrl":"https://doi.org/10.29354/diag/152276","url":null,"abstract":"The work of solar cells and their production of electrical energy have been affected by climate change, especially in hot regions which became significantly hotter and still receive relatively high levels of solar radiation throughout the year. Higher ambient temperature and solar radiation result in higher PV cell temperature and, therefore, the reduction in PV module power output and efficiency. This study investigates how a PV module performs throughout the year in a hot region by considering the variations in cell temperature resulting from changes in ambient temperature and solar radiation every day. The tilt angles and two-axis tracking have also been examined. Results indicate that the two-axis solar tracking system is critical to use in hot regions for obtaining higher output power. Therefore, part of this power can be used to cool solar panels using various methods to keep their efficiency high, such as operating air fans or operating pumps to cool them with coolant.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44941161","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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