Pub Date : 2022-08-01DOI: 10.14489/td.2022.08.pp.004-013
A. G. Sokolova, F. Balitsky, V. D. Sizarev
In the development of vibration condition monitoring technology of the movable reflector PO-3 of the IBR-2 research reactor with using S-discriminant vibration analysis [1], the paper presents data and results of a correlation assessment of the stochastic interrelationship degree between S-discriminant and spectral functions in various frequency bands over 8 years of operation of the installation. This made it possible to identify the main sources of vibration activity of units of neutron reflector, developing operational malfunctions of some of its bearings and their influence on changes in its vibration and technical condition.
{"title":"EXPERT ASSESSMENT OF THE PO-3 MOBILE NEUTRON REFLECTOR CONDITION OF THE IBR-2 REACTOR WITH USING DISCRIMINANT AND CORRELATION METHODS OF ITS VIBRATION ANALYSIS","authors":"A. G. Sokolova, F. Balitsky, V. D. Sizarev","doi":"10.14489/td.2022.08.pp.004-013","DOIUrl":"https://doi.org/10.14489/td.2022.08.pp.004-013","url":null,"abstract":"In the development of vibration condition monitoring technology of the movable reflector PO-3 of the IBR-2 research reactor with using S-discriminant vibration analysis [1], the paper presents data and results of a correlation assessment of the stochastic interrelationship degree between S-discriminant and spectral functions in various frequency bands over 8 years of operation of the installation. This made it possible to identify the main sources of vibration activity of units of neutron reflector, developing operational malfunctions of some of its bearings and their influence on changes in its vibration and technical condition.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134552447","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.050-055
M. K. Kadhim, L. Rusinov
Ceramic tiles are one of the most demanded finishing materials, and the areas of their use are constantly expanding. The production of ceramic tiles is quite well automated, but the control of manufactured tiles for defects is usually not automated, that limits its speed and does not guarantee the necessary quality. The algorithm for detecting the main surface defects of ceramic tiles, namely, mechanical (scratches, cracks, etc.), geometric (chips on the corners, gouges or protrusions on the edges), color defects (blobs, spots, etc.) is proposed in the paper. It based on digital image processing of tiles and was implemented using the free library of algorithmic primitives OpenCV. The algorithm does not require the presentation of reference tiles. At the same time, a high speed of classifying monochrome tiles into fresh and defective ones is ensured and allows to organize the automatic control of plain tiles on the conveyor in real time with the probability of correct detections 97 %.
{"title":"AUTOMATIC DETECTION OF SURFACE DEFECTS OF CERAMIC TILES","authors":"M. K. Kadhim, L. Rusinov","doi":"10.14489/td.2022.07.pp.050-055","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.050-055","url":null,"abstract":"Ceramic tiles are one of the most demanded finishing materials, and the areas of their use are constantly expanding. The production of ceramic tiles is quite well automated, but the control of manufactured tiles for defects is usually not automated, that limits its speed and does not guarantee the necessary quality. The algorithm for detecting the main surface defects of ceramic tiles, namely, mechanical (scratches, cracks, etc.), geometric (chips on the corners, gouges or protrusions on the edges), color defects (blobs, spots, etc.) is proposed in the paper. It based on digital image processing of tiles and was implemented using the free library of algorithmic primitives OpenCV. The algorithm does not require the presentation of reference tiles. At the same time, a high speed of classifying monochrome tiles into fresh and defective ones is ensured and allows to organize the automatic control of plain tiles on the conveyor in real time with the probability of correct detections 97 %.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129631651","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.014-025
A. N. Seryeznov, L. Stepanova, S. Kabanov, I. Ramazanov, A. Kuznetsov, V. Chernova
Samples of carbon fiber T 700 were researched. They were subjected to impact damage, after which they were loaded with a static load until failure. Registration of defects was carried out using the method of acoustic emission (AE) and tensometry. In the process of loading the samples, the deformation and load were determined, at which the AE signals were located. An antenna consisting of piezoelectric acoustic emission transducers (PAE) and fiber optic sensors (FOS) was used to monitor defects. When the load changed from 80 to 100 kN, a jump in mechanical stresses was observed in the samples from 338 to 432 MPa, registered by the certified microprocessor-based high-speed tensometic system “Dynamics-3”. In this case, the average amplitude of the AE signals significantly decreased, starting from the load P = 80 kN, after which it increased at the load P = 110 kN. For sensors PAE 3 and VOD 2, located on the opposite side of the sample, where impact damage was absent, these changes in the amplitudes of the AE signals were less pronounced.
{"title":"TESTING OF CFRP SPECIMENS WITH IMPACT DAMAGE USING THE ACOUSTIC EMISSION METHOD AND TENSOMETRY","authors":"A. N. Seryeznov, L. Stepanova, S. Kabanov, I. Ramazanov, A. Kuznetsov, V. Chernova","doi":"10.14489/td.2022.07.pp.014-025","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.014-025","url":null,"abstract":"Samples of carbon fiber T 700 were researched. They were subjected to impact damage, after which they were loaded with a static load until failure. Registration of defects was carried out using the method of acoustic emission (AE) and tensometry. In the process of loading the samples, the deformation and load were determined, at which the AE signals were located. An antenna consisting of piezoelectric acoustic emission transducers (PAE) and fiber optic sensors (FOS) was used to monitor defects. When the load changed from 80 to 100 kN, a jump in mechanical stresses was observed in the samples from 338 to 432 MPa, registered by the certified microprocessor-based high-speed tensometic system “Dynamics-3”. In this case, the average amplitude of the AE signals significantly decreased, starting from the load P = 80 kN, after which it increased at the load P = 110 kN. For sensors PAE 3 and VOD 2, located on the opposite side of the sample, where impact damage was absent, these changes in the amplitudes of the AE signals were less pronounced.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128027509","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.004-013
V. Ushakov, V. Danilov
The results of ultrasonic testing of metal before and after the operation of pipelines of thermal power plants are presented. Based on the metallographic analysis data, the frequency of ultrasonic waves was selected for research 10 and 15 MHz. It was found that the smallest effect of the surface roughness of the tested samples from the 12X1MF (Ra = 0.07…3.50 microns) was observed at a frequency of 15 MHz. It is shown that on the rough surface of samples Ra = 1.17…2.50 microns, the ratio of the amplitude of the 3rd bottom echo to the amplitude of the average noise level decreases to 17 dB at a frequency of 15 MHz with a metal operating time of 300 000 hours. The specified parameter is proposed to be used in metal structroscopy by ultrasonic method. It is shown that the shape of the pulse and its spectrum are subject to the greatest distortion at a frequency of ultrasonic waves equal to 15 MHz.
{"title":"INVESTIGATION OF METAL STRUCTURE BY NON-DESTRUCTIVE ULTRASONIC METHOD","authors":"V. Ushakov, V. Danilov","doi":"10.14489/td.2022.07.pp.004-013","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.004-013","url":null,"abstract":"The results of ultrasonic testing of metal before and after the operation of pipelines of thermal power plants are presented. Based on the metallographic analysis data, the frequency of ultrasonic waves was selected for research 10 and 15 MHz. It was found that the smallest effect of the surface roughness of the tested samples from the 12X1MF (Ra = 0.07…3.50 microns) was observed at a frequency of 15 MHz. It is shown that on the rough surface of samples Ra = 1.17…2.50 microns, the ratio of the amplitude of the 3rd bottom echo to the amplitude of the average noise level decreases to 17 dB at a frequency of 15 MHz with a metal operating time of 300 000 hours. The specified parameter is proposed to be used in metal structroscopy by ultrasonic method. It is shown that the shape of the pulse and its spectrum are subject to the greatest distortion at a frequency of ultrasonic waves equal to 15 MHz.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129566264","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.026-031
V. Matveev, A. S. Bazhanov
The article discusses modern microradiowave methods and means of remote control of parameters of dynamic processes associated with movement, rotation, change of position and condition of objects of control. The main advantages of the methods are contactlessness, remoteness, inertia-free and efficiency. Examples of developments that implement the capabilities of microradiowave methods for monitoring dynamic processes are given. Advantages and prospects are shown.
{"title":"CONTROL OF DYNAMIC PROCESSES USING MICRORADIOWAVES","authors":"V. Matveev, A. S. Bazhanov","doi":"10.14489/td.2022.07.pp.026-031","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.026-031","url":null,"abstract":"The article discusses modern microradiowave methods and means of remote control of parameters of dynamic processes associated with movement, rotation, change of position and condition of objects of control. The main advantages of the methods are contactlessness, remoteness, inertia-free and efficiency. Examples of developments that implement the capabilities of microradiowave methods for monitoring dynamic processes are given. Advantages and prospects are shown.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128963279","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.042-048
A. Bazulin, A. Butov, D. Tikhonov, S. Romashkin
To perform ultrasonic testing of golden joints of the main gas pipeline, a procedure for mechanized ultrasonic testing was developed. The procedure complied with the requirements of EN ISO 13588:2019 inspection level C and EN ISO 10863:2020 inspection level C. Testing for transverse defects was carried out using conventional piezoelectric transducers using the echo-mirror method and frontal SAFT processing. The use of the AUGUR-ART flaw detector, the SPIDER scanner and the ECHO-scan and AUGUR-Analysis software demonstrated stable detection of defect simulators in the reference block. All this made it possible to analyze the shortcomings of welding at training joints and successfully perform golden joints of the main gas pipeline.
为了对主燃气管道金接头进行超声检测，开发了一种机械化超声检测方法。该程序符合EN ISO 13588:2019检验等级C和EN ISO 10863:2020检验等级C的要求。采用传统的压电换能器，采用回波镜法和正面SAFT处理进行横向缺陷检测。使用AUGUR-ART探伤仪、SPIDER扫描仪、echo扫描和AUGUR-Analysis软件对参考块中的缺陷模拟器进行了稳定的检测。这为分析训练接头焊接的缺陷，成功完成主燃气管道的黄金接头提供了可能。
{"title":"MECHANIZED ULTRASONIC INSPECTION OF TIEIN WELDS OF THE MAIN GAS PIPELINE WITH AN AUGUR-ART FLAW DETECTOR","authors":"A. Bazulin, A. Butov, D. Tikhonov, S. Romashkin","doi":"10.14489/td.2022.07.pp.042-048","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.042-048","url":null,"abstract":"To perform ultrasonic testing of golden joints of the main gas pipeline, a procedure for mechanized ultrasonic testing was developed. The procedure complied with the requirements of EN ISO 13588:2019 inspection level C and EN ISO 10863:2020 inspection level C. Testing for transverse defects was carried out using conventional piezoelectric transducers using the echo-mirror method and frontal SAFT processing. The use of the AUGUR-ART flaw detector, the SPIDER scanner and the ECHO-scan and AUGUR-Analysis software demonstrated stable detection of defect simulators in the reference block. All this made it possible to analyze the shortcomings of welding at training joints and successfully perform golden joints of the main gas pipeline.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131133156","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.056-061
A. G. Otoka, A. Lyakh
A brief overview of the operational defects of bearing rings detected by the magnetic powder method is given. Various installations used on the railway are presented with a description of the control technology. Photographs with indicator drawings of defects detected by the magnetic powder method are shown.
{"title":"DETECTION OF BEARING RING DEFECTS MAGNETIC POWDER METHOD RESIDUAL MAGNETIZATION METHOD","authors":"A. G. Otoka, A. Lyakh","doi":"10.14489/td.2022.07.pp.056-061","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.056-061","url":null,"abstract":"A brief overview of the operational defects of bearing rings detected by the magnetic powder method is given. Various installations used on the railway are presented with a description of the control technology. Photographs with indicator drawings of defects detected by the magnetic powder method are shown.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"231 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114196689","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 : 2022-07-01DOI: 10.14489/td.2022.07.pp.032-041
A. Vanyagin, B. Gordeev, S. Okhulkov, A. Ermolaev
To automate the operation of power units of vehicles and machining centers, it is necessary to develop reliable methods and means of measuring the main parameters characterizing their operation: torque, shaft power, axial shaft force, etc. Contactless magnetoelastic torque sensors are distinguished by high operational suitability, the measuring circuits of which, however, are obsolete and do not meet the increased requirements for measurement accuracy. The paper presents the design and describes the principle of operation of a contactless magnetoelastic torque sensor, a comparison of existing measuring circuits is given. The authors proposed a new technical solution for measuring torque, implemented on the basis of a phase shift meter with broadband frequency modulation of oscillators of swinging frequency. The test results of the prototype of the new measuring circuit demonstrated high accuracy and sensitivity compared to traditional measuring circuits. The new measuring circuit is not susceptible to errors in the electrical parameters of electronic components.
{"title":"HIGH-FREQUENCY OSCILLATORS OF SWINGING FREQUENCY IN THE OUTPUT CIRCUITS OF MAGNETOELASTIC TORQUE SENSORS","authors":"A. Vanyagin, B. Gordeev, S. Okhulkov, A. Ermolaev","doi":"10.14489/td.2022.07.pp.032-041","DOIUrl":"https://doi.org/10.14489/td.2022.07.pp.032-041","url":null,"abstract":"To automate the operation of power units of vehicles and machining centers, it is necessary to develop reliable methods and means of measuring the main parameters characterizing their operation: torque, shaft power, axial shaft force, etc. Contactless magnetoelastic torque sensors are distinguished by high operational suitability, the measuring circuits of which, however, are obsolete and do not meet the increased requirements for measurement accuracy. The paper presents the design and describes the principle of operation of a contactless magnetoelastic torque sensor, a comparison of existing measuring circuits is given. The authors proposed a new technical solution for measuring torque, implemented on the basis of a phase shift meter with broadband frequency modulation of oscillators of swinging frequency. The test results of the prototype of the new measuring circuit demonstrated high accuracy and sensitivity compared to traditional measuring circuits. The new measuring circuit is not susceptible to errors in the electrical parameters of electronic components.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"210 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114979745","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 : 2022-06-01DOI: 10.14489/td.2022.06.pp.038-047
Y. Altay, A. Fedorov, K. A. Stepanova
In this article, a method for processing acoustic information is presented to assess the correlation relationship of information components and noise of acoustic emission (AE) signals. The method is based on a polynomial approximation of bidirectional Butterworth high and low pass filters. The operability of the processing method on full-scale samples of the noisy AE signal is analyzed and the evaluation of the received processing is carried out on the basis of quantitative indicators. Bidirectional implementation of high-pass filters improves the quality of processing when compared with a low-pass filter. To assess the correlation relationship using the considered processing method, fragments of the information component and noise are isolated from the noisy signal. Based on the selected components, a high correlation relationship between AE information signals and noise has been established.
{"title":"ESTIMATION OF RELATIONSHIP BETWEEN INFORMATION COMPONENTS AND NOISE OF ACOUSTIC EMISSION SIGNALS","authors":"Y. Altay, A. Fedorov, K. A. Stepanova","doi":"10.14489/td.2022.06.pp.038-047","DOIUrl":"https://doi.org/10.14489/td.2022.06.pp.038-047","url":null,"abstract":"In this article, a method for processing acoustic information is presented to assess the correlation relationship of information components and noise of acoustic emission (AE) signals. The method is based on a polynomial approximation of bidirectional Butterworth high and low pass filters. The operability of the processing method on full-scale samples of the noisy AE signal is analyzed and the evaluation of the received processing is carried out on the basis of quantitative indicators. Bidirectional implementation of high-pass filters improves the quality of processing when compared with a low-pass filter. To assess the correlation relationship using the considered processing method, fragments of the information component and noise are isolated from the noisy signal. Based on the selected components, a high correlation relationship between AE information signals and noise has been established.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129017352","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 : 2022-06-01DOI: 10.14489/td.2022.06.pp.024-029
N. R. Kharlamov, A. D. Kiryanova, N. Larionov, V. Karakeyan, A. S. Ryabyshenkov
The results of the assessment of the composition of emissions of pollutants during the process of epitaxy into the atmosphere are presented. Using the example of a typical model of the epitaxy process and instrumental measurements, it was found that in the air removed from the epitaxy and charge discharge installations, the lead content is at the level of 99 %. Based on the material balance, the total lead emission capacity and its gross values are determined for the current and expanded production scale. It is shown that with an increase in the volume of production, the size of the sanitary protection zone of the enterprise is subject to revision in the direction of increase.
{"title":"ASSESSMENT OF THE AMOUNT OF EMISSIONS OF POLLUTANTS INTO THE ATMOSPHERE","authors":"N. R. Kharlamov, A. D. Kiryanova, N. Larionov, V. Karakeyan, A. S. Ryabyshenkov","doi":"10.14489/td.2022.06.pp.024-029","DOIUrl":"https://doi.org/10.14489/td.2022.06.pp.024-029","url":null,"abstract":"The results of the assessment of the composition of emissions of pollutants during the process of epitaxy into the atmosphere are presented. Using the example of a typical model of the epitaxy process and instrumental measurements, it was found that in the air removed from the epitaxy and charge discharge installations, the lead content is at the level of 99 %. Based on the material balance, the total lead emission capacity and its gross values are determined for the current and expanded production scale. It is shown that with an increase in the volume of production, the size of the sanitary protection zone of the enterprise is subject to revision in the direction of increase.","PeriodicalId":432853,"journal":{"name":"Kontrol'. Diagnostika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130648031","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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