To tackle the inefficiency of terahertz (THz)-based C-scan defect detection for thermal barrier coatings (TBCs), a dual-channel convolutional neural network–based THz fast imaging method is proposed. In this paper, the finite-difference time-domain (FDTD) method is used to prepare the training set. In the numerical simulation, the actual C-scan step is simulated by grid division of different sizes. The large step THz image is preliminarily reconstructed by bicubic interpolation, and then the deep and shallow features in the image are extracted by the dual-channel convolution neural network and the image under small step is reconstructed by different weight refusion, so as to improve the detection efficiency by reducing the number of C-scan points. Gaussian white noise with different distributions is employed when simulating the real test image. The experimental results show that compared with bicubic, ICBI, SRCNN, and ResNet, the dual-channel convolutional neural network improves PSNR (peak signal-to-noise ratio) by 2.85, 2.81, 2.25, and 1.54, and improves by 0.019, 0.014, 0.014, and 0.009 on SSIM (structural similarity).
{"title":"A Terahertz Fast Imaging Method for Debonding Defects of Thermal Barrier Coatings Based on Dual-Channel Convolutional Neural Network","authors":"Binghua Cao, Dalin Yang, Mengbao Fan","doi":"10.32548/2023.me-04302","DOIUrl":"https://doi.org/10.32548/2023.me-04302","url":null,"abstract":"To tackle the inefficiency of terahertz (THz)-based C-scan defect detection for thermal barrier coatings (TBCs), a dual-channel convolutional neural network–based THz fast imaging method is proposed. In this paper, the finite-difference time-domain (FDTD) method is used to prepare the training set. In the numerical simulation, the actual C-scan step is simulated by grid division of different sizes. The large step THz image is preliminarily reconstructed by bicubic interpolation, and then the deep and shallow features in the image are extracted by the dual-channel convolution neural network and the image under small step is reconstructed by different weight refusion, so as to improve the detection efficiency by reducing the number of C-scan points. Gaussian white noise with different distributions is employed when simulating the real test image. The experimental results show that compared with bicubic, ICBI, SRCNN, and ResNet, the dual-channel convolutional neural network improves PSNR (peak signal-to-noise ratio) by 2.85, 2.81, 2.25, and 1.54, and improves by 0.019, 0.014, 0.014, and 0.009 on SSIM (structural similarity).","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48354415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Karim Yosefpour Shirsavar, M. Abbasi, S. J. Hosseinipour
In this paper, the results of nondestructive evaluation, structure characteristics, and magnetic properties of HP-Nb steam reformer tubes of a direct reduction unit are presented. An eddy current testing technique based on a special normal probe was performed to estimate the service life of the outer surface of the reformer tubes at a frequency of 60 kHz. The magnetic properties were investigated by vibrating sample magnetometer testing. Microstructural transformations of reference samples were performed by an optical microscope equipped with image analysis software and scanning electron microscopes. With exposure to severe operational conditions in oxidizing atmospheres and high temperature, microstructural changes such as oxidation and transformation of M23C6 and M7C3 carbide in the carburization zone, and chromium depletion in the austenite matrix, can be intensified. The tubes were inspected on a point basis and the eddy current data were presented as an impedance map. The results of the eddy current testing and vibrating sample magnetometer showed that microstructural changes due to operational conditions affect the electromagnetic response of the tubes.
{"title":"Investigation of Microstructure and Magnetic Properties of HP40-Nb Reformer Tubes","authors":"Karim Yosefpour Shirsavar, M. Abbasi, S. J. Hosseinipour","doi":"10.32548/2023.me-04308","DOIUrl":"https://doi.org/10.32548/2023.me-04308","url":null,"abstract":"In this paper, the results of nondestructive evaluation, structure characteristics, and magnetic properties of HP-Nb steam reformer tubes of a direct reduction unit are presented. An eddy current testing technique based on a special normal probe was performed to estimate the service life of the outer surface of the reformer tubes at a frequency of 60 kHz. The magnetic properties were investigated by vibrating sample magnetometer testing. Microstructural transformations of reference samples were performed by an optical microscope equipped with image analysis software and scanning electron microscopes. With exposure to severe operational conditions in oxidizing atmospheres and high temperature, microstructural changes such as oxidation and transformation of M23C6 and M7C3 carbide in the carburization zone, and chromium depletion in the austenite matrix, can be intensified. The tubes were inspected on a point basis and the eddy current data were presented as an impedance map. The results of the eddy current testing and vibrating sample magnetometer showed that microstructural changes due to operational conditions affect the electromagnetic response of the tubes.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47887027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Troitskiy, M. Karmanov, S. R. Mikhailov, R. Pastovenskiy, V. Shalaev
For the nondestructive testing of long objects at the Paton Electric Welding Institute (Ukraine), an X-ray detector was created that uses a digital medical mini sensor. To increase the testing area, adjacent digital X-ray images are stored and stitched together by software into a combined image. The thickness of the objects that can be tested with this type of sensor, which has a maximal voltage of 70 kV, is 6 mm for aluminum. This imaging process can be used in a wide variety of applications. In a second approach, we developed a mobile detector with a remote control for radiographic testing (RT) of objects in limited and hard-to-reach spaces. One application utilizes a robotic car with independently controlled magnetic wheels that allows the detector to move in any direction over the entire surface of the object under test.
{"title":"Scanning X-Ray Detector For Nondestructive Testing","authors":"V. Troitskiy, M. Karmanov, S. R. Mikhailov, R. Pastovenskiy, V. Shalaev","doi":"10.32548/2023.me-04290","DOIUrl":"https://doi.org/10.32548/2023.me-04290","url":null,"abstract":"For the nondestructive testing of long objects at the Paton Electric Welding Institute (Ukraine), an X-ray detector was created that uses a digital medical mini sensor. To increase the testing area, adjacent digital X-ray images are stored and stitched together by software into a combined image. The thickness of the objects that can be tested with this type of sensor, which has a maximal voltage of 70 kV, is 6 mm for aluminum. This imaging process can be used in a wide variety of applications. \u0000In a second approach, we developed a mobile detector with a remote control for radiographic testing (RT) of objects in limited and hard-to-reach spaces. One application utilizes a robotic car with independently controlled magnetic wheels that allows the detector to move in any direction over the entire surface of the object under test.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43173520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article addresses the question: What effects do different types of wedge materials have, if any, on frequency filtering in high-frequency time of flight diffraction scanning?
{"title":"High-Frequency Filtering of Wedge Materials for TOFD","authors":"J. Ellis","doi":"10.32548/2023.me-04313","DOIUrl":"https://doi.org/10.32548/2023.me-04313","url":null,"abstract":"This article addresses the question: What effects do different types of wedge materials have, if any, on frequency filtering in high-frequency time of flight diffraction scanning?","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":"68 10","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41284235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As part of the technical program at the 30th ASNT Research Symposium, held in June 2022 in St. Louis, Missouri, a two-part distinct and relevant-to-the-topic event took place. There have been similar events held at various nondestructive evaluation (NDE)-related events in the past, discussing similar issues and challenges.1,2 The first part featured an education session, in which several invited speakers engaged in NDE education at a community college and at several universities (some in association with Los Alamos National Laboratory) presented an overview of their NDE academic programs, challenges they endure in sustaining their programs, and their perspective on what is required to sustain and move their programs forward. The second part included a panel discussion and subsequent breakout sessions. A detailed background on these two program components and the collective discussions that took place during this event are presented in this article.
{"title":"National Alliance for NDE Education and Workforce Development – Current Challenges and Potential Paths Forward","authors":"Katelyn R. Brinker, R. Zoughi","doi":"10.32548/2023.me-04330","DOIUrl":"https://doi.org/10.32548/2023.me-04330","url":null,"abstract":"As part of the technical program at the 30th ASNT Research Symposium, held in June 2022 in St. Louis, Missouri, a two-part distinct and relevant-to-the-topic event took place. There have been similar events held at various nondestructive evaluation (NDE)-related events in the past, discussing similar issues and challenges.1,2 The first part featured an education session, in which several invited speakers engaged in NDE education at a community college and at several universities (some in association with Los Alamos National Laboratory) presented an overview of their NDE academic programs, challenges they endure in sustaining their programs, and their perspective on what is required to sustain and move their programs forward. The second part included a panel discussion and subsequent breakout sessions. A detailed background on these two program components and the collective discussions that took place during this event are presented in this article.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41521963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paul Adams, A. Gregorian, S. Kenderian, S. Sitzman
Image quality indicators (IQIs) are used to ensure quality in radiography. The requirements for hole-type IQIs have changed from MIL-STD-453-C (US DOD 1984) to ASTM E1742 and E1025 (ASTM 2018a, 2018b). For materials thinner than 0.50 in., the 2-2T hole does not represent 2% sensitivity. E1025 introduced true-T hole IQIs, where the 2-2T hole represents 2% sensitivity. Stainless steel true-T hole IQIs were fabricated using drills and a plasma-focused ion beam instrument. They were imaged using digital radiography (DR), computed radiography, and X-ray film to determine the limit of their visibility. DR was able to detect holes on the order of 2 to 3 pixels in diameter. All three techniques were able to detect the 2T hole in the number 4 IQI while DR was able to detect it in the number 3 IQI. These hole sizes are near the limit where geometric magnification would be required. The better sensitivity of DR is probably a result of being able to minimize fixed structural noise. Presently, for materials thinner than 0.50 in., there is the option to use IQIs defined by either E1742 Annex A1 or E1025. It is recommended that inspection procedures require a particular sensitivity percent that would necessitate the use of a specific IQI.
图像质量指标(iqi)用于保证放射照相的质量。孔型iqi的要求已从MIL-STD-453-C (US DOD 1984)更改为ASTM E1742和E1025 (ASTM 2018a, 2018b)。适用于厚度小于0.50英寸的材料。， 2-2T孔不代表2%的灵敏度。E1025引入了真t孔IQIs，其中2-2T孔代表2%的灵敏度。利用钻头和等离子体聚焦离子束仪器制备了不锈钢真t孔IQIs。使用数字放射照相(DR)、计算机放射照相和x射线胶片对其进行成像，以确定其可见性的极限。DR能够探测到直径为2到3个像素的孔。这三种技术均能检测到4号IQI中的2T孔，而DR能检测到3号IQI中的2T孔。这些孔的尺寸接近几何放大的极限。DR较好的灵敏度可能是由于能够将固定结构噪声降至最低。目前，对于厚度小于0.50英寸的材料。，可以选择使用E1742附录A1或E1025定义的iqi。建议检验程序要求特定的灵敏度百分比，这将需要使用特定的IQI。
{"title":"Detectability of Small True-T Hole Image Quality Indicators by Digital Radiographic Techniques","authors":"Paul Adams, A. Gregorian, S. Kenderian, S. Sitzman","doi":"10.32548/2023.me-04315","DOIUrl":"https://doi.org/10.32548/2023.me-04315","url":null,"abstract":"Image quality indicators (IQIs) are used to ensure quality in radiography. The requirements for hole-type IQIs have changed from MIL-STD-453-C (US DOD 1984) to ASTM E1742 and E1025 (ASTM 2018a, 2018b). For materials thinner than 0.50 in., the 2-2T hole does not represent 2% sensitivity. E1025 introduced true-T hole IQIs, where the 2-2T hole represents 2% sensitivity. Stainless steel true-T hole IQIs were fabricated using drills and a plasma-focused ion beam instrument. They were imaged using digital radiography (DR), computed radiography, and X-ray film to determine the limit of their visibility. DR was able to detect holes on the order of 2 to 3 pixels in diameter. All three techniques were able to detect the 2T hole in the number 4 IQI while DR was able to detect it in the number 3 IQI. These hole sizes are near the limit where geometric magnification would be required. The better sensitivity of DR is probably a result of being able to minimize fixed structural noise. Presently, for materials thinner than 0.50 in., there is the option to use IQIs defined by either E1742 Annex A1 or E1025. It is recommended that inspection procedures require a particular sensitivity percent that would necessitate the use of a specific IQI.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43025730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The goal of this study is to investigate magnetic field characteristics corresponding to variations of the toughness of X70 pipeline steel under cyclic loading. After a series of stress-controlled cyclic loadings, the specimens were subjected to static tensile tests. Changes in the magnetic field were recorded simultaneously during the test. The results suggest that cyclic loadings will reduce the toughness of the material. The initial value and slope of the magnetic field-strain curve obtained in the static tensile test are related to the number of cyclic loadings. The evolutions of magnetic field and the stress-strain curve can reflect variations in the toughness of materials. Compared with the stress-strain curve, the magnetic field demonstrates the fatigue degradation process more markedly. The high sensitivity of the magnetic field to toughness may be used to estimate the degree of fatigue damage of steel.
{"title":"Piezomagnetic Behavior Corresponding to the Variations of the Toughness of X70 Steel Under Cyclic Loadings","authors":"S. Bao, Zhengye Zhao, Yan Li","doi":"10.32548/2023.me-04288","DOIUrl":"https://doi.org/10.32548/2023.me-04288","url":null,"abstract":"The goal of this study is to investigate magnetic field characteristics corresponding to variations of the toughness of X70 pipeline steel under cyclic loading. After a series of stress-controlled cyclic loadings, the specimens were subjected to static tensile tests. Changes in the magnetic field were recorded simultaneously during the test. The results suggest that cyclic loadings will reduce the toughness of the material. The initial value and slope of the magnetic field-strain curve obtained in the static tensile test are related to the number of cyclic loadings. The evolutions of magnetic field and the stress-strain curve can reflect variations in the toughness of materials. Compared with the stress-strain curve, the magnetic field demonstrates the fatigue degradation process more markedly. The high sensitivity of the magnetic field to toughness may be used to estimate the degree of fatigue damage of steel.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46315123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mina Torabi Milani, Jenna Del Fatti, Kimberley Orna, Yixin Zhang, A. Sinclair
A novel approach to designing the encapsulation for a high-temperature ultrasonic transducer to be capable of continuous operation over a temperature range of 25 to 650 °C is proposed. The transducer’s active element is a heavily damped lithium niobate disc of 3 MHz resonance frequency, operating in pulse-echo mode. The initial encapsulation design is developed based on the geometrical, thermal, mechanical, electrical, and ultrasonic requirements. Two finite element modeling systems are developed to analyze the thermal-induced stresses in the transducer at low and high temperatures as well as its ultrasonic performance. The simulation results are used to optimize the design before manufacturing a transducer prototype. The prototype is tested at room and elevated temperatures to verify performance.
{"title":"Design of an Ultrasonic Transducer Encapsulation for High-Temperature Applications","authors":"Mina Torabi Milani, Jenna Del Fatti, Kimberley Orna, Yixin Zhang, A. Sinclair","doi":"10.32548/2023.me-04314","DOIUrl":"https://doi.org/10.32548/2023.me-04314","url":null,"abstract":"A novel approach to designing the encapsulation for a high-temperature ultrasonic transducer to be capable of continuous operation over a temperature range of 25 to 650 °C is proposed. The transducer’s active element is a heavily damped lithium niobate disc of 3 MHz resonance frequency, operating in pulse-echo mode. The initial encapsulation design is developed based on the geometrical, thermal, mechanical, electrical, and ultrasonic requirements. Two finite element modeling systems are developed to analyze the thermal-induced stresses in the transducer at low and high temperatures as well as its ultrasonic performance. The simulation results are used to optimize the design before manufacturing a transducer prototype. The prototype is tested at room and elevated temperatures to verify performance.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44125717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to further prove the effectiveness of the sparse least-squares support vector regression (S-LS-SVR) method in damage detection, the authors used the S-LS-SVR model to locate actual damage sources of concrete. The data from acoustic emission testing (AE) are generated and filtered by the pullout test of reinforcement in concrete, and the three-dimensional coordinates of real-time damage sources in the failure process are provided through the model. The S-LS-SVR method is compared with the Newton iterative method and improved exhaustive method for positioning speed, positioning data utilization, and positioning accuracy. The results show that S-LS-SVR is superior to the two other time difference of arrival–based positioning methods in positioning speed, positioning data utilization, and positioning accuracy (data utilization is slightly lower than the improved exhaustive method). The location method based on S-LS-SVR provides the possibility for the application of AE technology in intelligent damage location of bridges, dams, and other service structures.
{"title":"Experimental Study On 3D Acoustic Emission Source Location of Concrete Based On Sparse Least-Squares Support Vector Regression","authors":"","doi":"10.32548/2023.me-04258","DOIUrl":"https://doi.org/10.32548/2023.me-04258","url":null,"abstract":"In order to further prove the effectiveness of the sparse least-squares support vector regression (S-LS-SVR) method in damage detection, the authors used the S-LS-SVR model to locate actual damage sources of concrete. The data from acoustic emission testing (AE) are generated and filtered by the pullout test of reinforcement in concrete, and the three-dimensional coordinates of real-time damage sources in the failure process are provided through the model. The S-LS-SVR method is compared with the Newton iterative method and improved exhaustive method for positioning speed, positioning data utilization, and positioning accuracy. The results show that S-LS-SVR is superior to the two other time difference of arrival–based positioning methods in positioning speed, positioning data utilization, and positioning accuracy (data utilization is slightly lower than the improved exhaustive method). The location method based on S-LS-SVR provides the possibility for the application of AE technology in intelligent damage location of bridges, dams, and other service structures.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43491733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-01DOI: 10.32548/2023.me-03-32.35/
This arrticle tells the story of women’s work in engineering and testing in the 20th century in the UK. During the First World War, large numbers of women were brought into the engineering workforce for munitions work. They were working with newly developed designs, techniques, and materials. For women who were interested in an engineering career, it seemed that this could be the start of a new profession for women, but they were later met with many obstacles.
{"title":"New Materials, New Profession: Women in Engineering, Materials, and Testing in the UK in the Early 20th Century","authors":"","doi":"10.32548/2023.me-03-32.35/","DOIUrl":"https://doi.org/10.32548/2023.me-03-32.35/","url":null,"abstract":"This arrticle tells the story of women’s work in engineering and testing in the 20th century in the UK. During the First World War, large numbers of women were brought into the engineering workforce for munitions work. They were working with newly developed designs, techniques, and materials. For women who were interested in an engineering career, it seemed that this could be the start of a new profession for women, but they were later met with many obstacles.","PeriodicalId":49876,"journal":{"name":"Materials Evaluation","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44791608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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