Ben Cloostermans, T. Baghdasaryan, D. Pronk, Björn Bruckenburg, F. Berghmans
Modern process industry, particularly (petro)chemical industry faces, many challenges pertaining to sustainability. In this respect, more stringent regulations on reducing emissions are motivating plant and process owners to implement condition monitoring and predictive maintenance strategies. Bolted flange connections equipped with sealing gaskets, for example, can be a significant source of emissions and their performance remains often ambiguous under modern standards. Gasket stress is a key performance indicator of a bolted flange connection, which is typically approximated using methods that rely on many simplifications and assumptions. This study investigates the potential of using fiber-optic sensors, more specifically fiber Bragg gratings, as strain sensors to estimate gasket stress in bolted flange connections with gaskets. To the best of our knowledge, it is the first time that said gaskets are instrumented with fiber Bragg gratings. For our experiments, we submit these gaskets to relevant mechanical loads, both in a laboratory setting and in a realistic industrial environment. We analyze the relation between the fiber Bragg grating response and the applied mechanical load to define transfer functions that allow estimating the gasket stress and hence the sealing performance of the flange connection.
{"title":"Estimation of sealing performance with quasi-distributed strain sensing in spiral wound gaskets","authors":"Ben Cloostermans, T. Baghdasaryan, D. Pronk, Björn Bruckenburg, F. Berghmans","doi":"10.1117/12.2679689","DOIUrl":"https://doi.org/10.1117/12.2679689","url":null,"abstract":"Modern process industry, particularly (petro)chemical industry faces, many challenges pertaining to sustainability. In this respect, more stringent regulations on reducing emissions are motivating plant and process owners to implement condition monitoring and predictive maintenance strategies. Bolted flange connections equipped with sealing gaskets, for example, can be a significant source of emissions and their performance remains often ambiguous under modern standards. Gasket stress is a key performance indicator of a bolted flange connection, which is typically approximated using methods that rely on many simplifications and assumptions. This study investigates the potential of using fiber-optic sensors, more specifically fiber Bragg gratings, as strain sensors to estimate gasket stress in bolted flange connections with gaskets. To the best of our knowledge, it is the first time that said gaskets are instrumented with fiber Bragg gratings. For our experiments, we submit these gaskets to relevant mechanical loads, both in a laboratory setting and in a realistic industrial environment. We analyze the relation between the fiber Bragg grating response and the applied mechanical load to define transfer functions that allow estimating the gasket stress and hence the sealing performance of the flange connection.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116967744","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}
F. Arcadio, Fiore Capasso, Chiara Marzano, L. Zeni, N. Cennamo
In this work, the classification and the identification of two different types of solvent solutions (i.e., isopropanol:water and ethanol:water) were achieved by exploiting the solvent solution properties combined with Artificial Intelligence. More in detail, a Surface Plasmon Resonance (SPR) sensor based on D-shaped plastic optical fibers (POFs) acted as an optical transducer to build a proper dataset. The plasmonic probe was used to monitor the bulk refractive index variations of the solvent solutions due to the evaporation phenomenon over time. The collected experimental data were used to train a machine learning-based algorithm useful for building a prediction model. In such a way, it was made possible to determine the presence of the solvent in the solution under test (water or alcoholic solutions) and, in addition, to recognize the type of solvent. Finally, the results obtained from the testing of unknown solutions testified to the goodness and suitability of the proposed simple sensing approach.
{"title":"Plasmonic plastic optical fiber chips combined with artificial intelligence to identify water or alcoholic solutions","authors":"F. Arcadio, Fiore Capasso, Chiara Marzano, L. Zeni, N. Cennamo","doi":"10.1117/12.2680771","DOIUrl":"https://doi.org/10.1117/12.2680771","url":null,"abstract":"In this work, the classification and the identification of two different types of solvent solutions (i.e., isopropanol:water and ethanol:water) were achieved by exploiting the solvent solution properties combined with Artificial Intelligence. More in detail, a Surface Plasmon Resonance (SPR) sensor based on D-shaped plastic optical fibers (POFs) acted as an optical transducer to build a proper dataset. The plasmonic probe was used to monitor the bulk refractive index variations of the solvent solutions due to the evaporation phenomenon over time. The collected experimental data were used to train a machine learning-based algorithm useful for building a prediction model. In such a way, it was made possible to determine the presence of the solvent in the solution under test (water or alcoholic solutions) and, in addition, to recognize the type of solvent. Finally, the results obtained from the testing of unknown solutions testified to the goodness and suitability of the proposed simple sensing approach.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122106558","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 presents a novel technique for the distributed measurement of the modal birefringence in a few-mode fiber (FMF). The method exploits two different phenomena observed in distributed Brillouin measurements: the dependence of the Brillouin frequency shift (BFS) on the effective refractive index (ERI) of the interacting optical beams, and the spatial oscillations of the Brillouin gain deriving from multimodal interference. Using both phenomena, a wide range of ERI separations can be measured, from ≈ 10-7 to 10-2 or more. The measurements have been carried out over a two-mode graded-index FMF, using two photonic lanterns to selectively excite the desired spatial modes. We use the BFS measurements to derive the ERI difference between the LP01 and LP11 mode groups, while the spatial oscillations of the Brillouin gain reveal the birefringence between the vector components (TE01, TM01 and HE21) of the LP11 mode group. The experimental measurements are partly supported by full-vector finite-element-method (FEM) simulations. The reported method may also find application in the field of distributed sensing, by taking advantage of the dependence of modal birefringence from physical parameters such as strain and temperature.
{"title":"Distributed measurement of modal birefringence in a few-mode fiber based on stimulated Brillouin scattering","authors":"E. Catalano, R. Vallifuoco, L. Zeni, A. Minardo","doi":"10.1117/12.2678089","DOIUrl":"https://doi.org/10.1117/12.2678089","url":null,"abstract":"This paper presents a novel technique for the distributed measurement of the modal birefringence in a few-mode fiber (FMF). The method exploits two different phenomena observed in distributed Brillouin measurements: the dependence of the Brillouin frequency shift (BFS) on the effective refractive index (ERI) of the interacting optical beams, and the spatial oscillations of the Brillouin gain deriving from multimodal interference. Using both phenomena, a wide range of ERI separations can be measured, from ≈ 10-7 to 10-2 or more. The measurements have been carried out over a two-mode graded-index FMF, using two photonic lanterns to selectively excite the desired spatial modes. We use the BFS measurements to derive the ERI difference between the LP01 and LP11 mode groups, while the spatial oscillations of the Brillouin gain reveal the birefringence between the vector components (TE01, TM01 and HE21) of the LP11 mode group. The experimental measurements are partly supported by full-vector finite-element-method (FEM) simulations. The reported method may also find application in the field of distributed sensing, by taking advantage of the dependence of modal birefringence from physical parameters such as strain and temperature.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123268686","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}
Martina Cappelletti, A. Aitkulov, Daniele Orsuti, L. Schenato, M. Santagiustina, M. Magarotto, C. Antonelli, A. Galtarossa, A. Mecozzi, T. Hayashi, L. Palmieri
This paper introduces a novel method to simultaneously measure the cores of a multi-core fiber, enabling higher acquisition rates in shape sensing. The two-dimensional shape of the optical fiber is determined from the distributed strain measurements performed with the optical frequency domain reflectometry technique.
{"title":"Fiber signature-domain multiplexing for high-speed shape sensing","authors":"Martina Cappelletti, A. Aitkulov, Daniele Orsuti, L. Schenato, M. Santagiustina, M. Magarotto, C. Antonelli, A. Galtarossa, A. Mecozzi, T. Hayashi, L. Palmieri","doi":"10.1117/12.2678899","DOIUrl":"https://doi.org/10.1117/12.2678899","url":null,"abstract":"This paper introduces a novel method to simultaneously measure the cores of a multi-core fiber, enabling higher acquisition rates in shape sensing. The two-dimensional shape of the optical fiber is determined from the distributed strain measurements performed with the optical frequency domain reflectometry technique.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127945600","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}
L. Rossi, L. Cheng, W. de Jong, R. Jansen, G. Bolognini
A low-noise φ-OTDR sensor is developed by adding a 2-stage pre-amplification system mixing linear and nonlinear amplification in a 3x3 Michelson interferometric configuration. Its performance is evaluated by deploying it as a distributed acoustic sensing system in a survey well (sampling rate: 10 kHz), showing noise floor levels below 1 nε
低噪声φ-OTDR传感器是通过在3x3迈克尔逊干涉配置中添加2级预放大系统混合线性和非线性放大而开发的。通过将其作为分布式声学传感系统部署在一口调查井中(采样率:10 kHz)来评估其性能，显示噪声底值低于1 ne ε
{"title":"Nonlinear amplification in φ-OTDR for distributed acoustic sensing","authors":"L. Rossi, L. Cheng, W. de Jong, R. Jansen, G. Bolognini","doi":"10.1117/12.2679397","DOIUrl":"https://doi.org/10.1117/12.2679397","url":null,"abstract":"A low-noise φ-OTDR sensor is developed by adding a 2-stage pre-amplification system mixing linear and nonlinear amplification in a 3x3 Michelson interferometric configuration. Its performance is evaluated by deploying it as a distributed acoustic sensing system in a survey well (sampling rate: 10 kHz), showing noise floor levels below 1 nε","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123784201","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}
M. Lindblom, Maximilian Patzauer, K. Hey Tow, Å. Claesson, Oscar Fogelberg, Toste Jonsäter, M. Warne
A fiber optic health-monitoring system for refractory lining in steel-making processes is presented. Its applicability as an early-warning system for lining damage is demonstrated by the results obtained in a field trial, in which 240 m of fiber was embedded in the lining of an electric arc furnace. The system is based on Raman distributed sensing and polyimide coated fibers in metal tube. The results presented from temperature cycling and calibration at temperatures up to 600 °C show that adequate accuracy and stability for the application can be attained.
{"title":"Refractory lining health monitoring based on Raman optical time domain reflectometry","authors":"M. Lindblom, Maximilian Patzauer, K. Hey Tow, Å. Claesson, Oscar Fogelberg, Toste Jonsäter, M. Warne","doi":"10.1117/12.2679296","DOIUrl":"https://doi.org/10.1117/12.2679296","url":null,"abstract":"A fiber optic health-monitoring system for refractory lining in steel-making processes is presented. Its applicability as an early-warning system for lining damage is demonstrated by the results obtained in a field trial, in which 240 m of fiber was embedded in the lining of an electric arc furnace. The system is based on Raman distributed sensing and polyimide coated fibers in metal tube. The results presented from temperature cycling and calibration at temperatures up to 600 °C show that adequate accuracy and stability for the application can be attained.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"24 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126874134","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}
F. Esposito, A. Stăncălie, A. Srivastava, M. Śmietana, J. Mrázek, R. Mihalcea, C. Neguț, S. Campopiano, A. Iadicicco
The investigation of impact of ionizing radiation on photonic waveguides and devices is of a large interest due to new demanding applications in harsh environments, such as space or high-energy-physics experiments and more. Thus, the effects of gamma radiation on refractive index inducing propagation loss different optical fibers are investigated by means of several approaches including fiber Bragg gratings and long period gratings (LPG). In this work, we report the results on exposure to gamma irradiation up to tens of kGy of LPGs written in single-mode optical fibers with unconventional dopants, such as B and P. The LPGs in a reflective configuration have been written using the electric arc discharge technique. The attention is focused on the real-time measurement of LPG resonance, i.e., wavelength shift and transmission power changes during irradiation, as well as the recovery effects after the irradiation. It has been found that the impact of gamma is significantly dependent on the fiber type and the LPG properties. The LPGs in B/Ge co-doped fiber show both the higher resonant wavelength shift and low power losses. Such results are useful for those working with optical fibers and related sensors in environments exposed to radiations.
{"title":"Response of long period gratings written in B/Ge and P-doped optical fibers to gamma radiation","authors":"F. Esposito, A. Stăncălie, A. Srivastava, M. Śmietana, J. Mrázek, R. Mihalcea, C. Neguț, S. Campopiano, A. Iadicicco","doi":"10.1117/12.2678163","DOIUrl":"https://doi.org/10.1117/12.2678163","url":null,"abstract":"The investigation of impact of ionizing radiation on photonic waveguides and devices is of a large interest due to new demanding applications in harsh environments, such as space or high-energy-physics experiments and more. Thus, the effects of gamma radiation on refractive index inducing propagation loss different optical fibers are investigated by means of several approaches including fiber Bragg gratings and long period gratings (LPG). In this work, we report the results on exposure to gamma irradiation up to tens of kGy of LPGs written in single-mode optical fibers with unconventional dopants, such as B and P. The LPGs in a reflective configuration have been written using the electric arc discharge technique. The attention is focused on the real-time measurement of LPG resonance, i.e., wavelength shift and transmission power changes during irradiation, as well as the recovery effects after the irradiation. It has been found that the impact of gamma is significantly dependent on the fiber type and the LPG properties. The LPGs in B/Ge co-doped fiber show both the higher resonant wavelength shift and low power losses. Such results are useful for those working with optical fibers and related sensors in environments exposed to radiations.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130882979","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}
Bastien Van Esbeen, D. Kinet, Corentin Guyot, A. Depré, Rik Knoppers, R. Nieuwland, C. Caucheteur
This paper reports on the development of a smart elastic textile band containing pre-strained fiber Bragg gratings (FBG) that was specifically designed with the ambition to dynamically measure the position of the backbone. To this aim, the textile band is 700 mm long and 60 mm wide. A piece of standard single-mode optical fiber, in which four fiber Bragg gratings were inscribed, is sewn on the band. Each FBG is glued on a 3D-printed pad in a pre-strained way, allowing the detection of FBG compression in addition to elongation. Measurements were performed on this sensing elastic band and the resulting sensitivity is a Bragg wavelength shift of 12 pm per mm of textile elongation. Validation tests were also carried out to highlight the sensitivity to compression and to show that the sensing system is capable of repeatability in a dynamic environment.
{"title":"Shape sensing with a smart elastic textile band containing pre-strained FBG sensors","authors":"Bastien Van Esbeen, D. Kinet, Corentin Guyot, A. Depré, Rik Knoppers, R. Nieuwland, C. Caucheteur","doi":"10.1117/12.2678400","DOIUrl":"https://doi.org/10.1117/12.2678400","url":null,"abstract":"This paper reports on the development of a smart elastic textile band containing pre-strained fiber Bragg gratings (FBG) that was specifically designed with the ambition to dynamically measure the position of the backbone. To this aim, the textile band is 700 mm long and 60 mm wide. A piece of standard single-mode optical fiber, in which four fiber Bragg gratings were inscribed, is sewn on the band. Each FBG is glued on a 3D-printed pad in a pre-strained way, allowing the detection of FBG compression in addition to elongation. Measurements were performed on this sensing elastic band and the resulting sensitivity is a Bragg wavelength shift of 12 pm per mm of textile elongation. Validation tests were also carried out to highlight the sensitivity to compression and to show that the sensing system is capable of repeatability in a dynamic environment.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131378364","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}
M. Götten, J. Van Roosbroeck, E. Lindner, S. Lochmann, J. Vlekken
In this contribution, the method of Code-division Multiplexing (CDM) is investigated for its dynamic measurement capabilities. In earlier publications, this technique has already been shown to be capable of measuring thousands of Draw Tower Grating® (DTGs®) in a single fiber, where many FBGs with identical wavelengths are used. The basics of CDM are explained. In addition, the ability to do dynamic measurements is investigated theoretically and experimentally and the results are presented. Good correspondence between theory and experiment could be found. Possible system improvements are proposed to find a suitable compromise between detection accuracy and system speed for massive optical sensor networks.
{"title":"Dynamic sensing of large arrays of draw tower gratings using code division multiplexing","authors":"M. Götten, J. Van Roosbroeck, E. Lindner, S. Lochmann, J. Vlekken","doi":"10.1117/12.2678082","DOIUrl":"https://doi.org/10.1117/12.2678082","url":null,"abstract":"In this contribution, the method of Code-division Multiplexing (CDM) is investigated for its dynamic measurement capabilities. In earlier publications, this technique has already been shown to be capable of measuring thousands of Draw Tower Grating® (DTGs®) in a single fiber, where many FBGs with identical wavelengths are used. The basics of CDM are explained. In addition, the ability to do dynamic measurements is investigated theoretically and experimentally and the results are presented. Good correspondence between theory and experiment could be found. Possible system improvements are proposed to find a suitable compromise between detection accuracy and system speed for massive optical sensor networks.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"443 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133365556","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}
K. Hey Tow, Joao Pereira, M. Lindblom, M. Fernández-Ruiz, H. Martins, M. Rossi, Siw Nilsson, Harald van den Berg
Fibre-optic based sensing technologies are becoming popular in the field of geophysics since enable long range and high spatial resolution acoustic measurements. In this work, we present preliminary results obtained using quasi-distributed Fibre-Bragg grating sensing and Distributed Acoustic Sensing (DAS) to monitor seismic activities in an operational underground mine. 12 FBGs and 800 metres of fiber optic cable was installed in the tunnel lining an operational mine and recorded mine seismicity such as production blasts and a small seismic activity of magnitude 1.41 in September 2022.
{"title":"Monitoring mining induced seismicity using optical fibre sensors during mine exploitation","authors":"K. Hey Tow, Joao Pereira, M. Lindblom, M. Fernández-Ruiz, H. Martins, M. Rossi, Siw Nilsson, Harald van den Berg","doi":"10.1117/12.2678296","DOIUrl":"https://doi.org/10.1117/12.2678296","url":null,"abstract":"Fibre-optic based sensing technologies are becoming popular in the field of geophysics since enable long range and high spatial resolution acoustic measurements. In this work, we present preliminary results obtained using quasi-distributed Fibre-Bragg grating sensing and Distributed Acoustic Sensing (DAS) to monitor seismic activities in an operational underground mine. 12 FBGs and 800 metres of fiber optic cable was installed in the tunnel lining an operational mine and recorded mine seismicity such as production blasts and a small seismic activity of magnitude 1.41 in September 2022.","PeriodicalId":424244,"journal":{"name":"European Workshop on Optical Fibre Sensors","volume":"87 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114040669","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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