Engineering Failure Analysis最新文献_第10页

File wear analysis of root canal treatment in simulated root canals – A vibrational and high-speed imagery approach

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-24 DOI: 10.1016/j.engfailanal.2025.109428

Apoorv Tripathi , Janmejai Sharma , Pavan Kumar Kankar , Ankur Miglani

{"title":"File wear analysis of root canal treatment in simulated root canals – A vibrational and high-speed imagery approach","authors":"Apoorv Tripathi , Janmejai Sharma , Pavan Kumar Kankar , Ankur Miglani","doi":"10.1016/j.engfailanal.2025.109428","DOIUrl":"10.1016/j.engfailanal.2025.109428","url":null,"abstract":"<div><div>A typical root canal treatment involves − cleaning, shaping, and enlarging the root canals<strong>.</strong> In RCT, the probability of defects related to file fatigue and failure is high. This study aims to investigate the vibrations generated during root canal preparation of simulated root canals using a triaxial accelerometer. Experiments are conducted systematically until file failure, and each failure time analyzed from the raw data. Denoising of vibration signals was done by SWT (coif3 mother wavelet). Finally, statistical parameters were extracted from the raw data to find correlations between successive file runs for each block used for root canal preparation. The vibrational signals upon denoising reveals that the amplitude of vibration is found to be highest in the curved sections of the canals which ultimately leads to the fatigue failure of the WOG files. The root cause assessment for the WOG file failure dealt with high-speed imaging and FESEM assisted fractography analysis The high-speed imaging in a backlit system revealed an unwinding of WOG files before fatigue failure. This provided evidence to support unwinding of files prior to fracture which typically occurred in the curved section of the acrylic block. Furthermore, discernments into the modes and mechanism of failure are provided via FESEM of the failed file fragments. The fracture morphology reveals a combinational fatigue failure as unwinding, crack initiation and propagation coupled with micro void formation and coalescence due to torsional shear and bending stresses. Overall, this study provides insights into the real-time monitoring and prediction of failure of endodontic files which can aid in devising strategies in preventing accidents during a typical RCT.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109428"},"PeriodicalIF":4.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and numerical analysis on Tri-Segment T-Girders with different joint types

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-24 DOI: 10.1016/j.engfailanal.2025.109430

Xiangyong Duanmu , Dong Xu , Penghui Zhang , Guoxi Tang , Chang Liu

{"title":"Experimental and numerical analysis on Tri-Segment T-Girders with different joint types","authors":"Xiangyong Duanmu , Dong Xu , Penghui Zhang , Guoxi Tang , Chang Liu","doi":"10.1016/j.engfailanal.2025.109430","DOIUrl":"10.1016/j.engfailanal.2025.109430","url":null,"abstract":"<div><div>Precast concrete bridges are valued for their standardization and efficiency, but transportation challenges limit their use in mountainous areas. The Tri-Segment T-Girder bridge, a type of precast segmental concrete bridges, effectively reduces segment lengths. This study examines commonly used epoxy joints in Tri-Segment T-Girder, including flat epoxy joints, steel shear key joints, and steel rebar joints. Three-point bending tests were performed on three Tri-Segment T-Girder specimens, each measuring 7.78 meters in length. The experimental results showed that steel rebars through the joint (SR-TJs) significantly enhanced the crack resistance of the girders, although they reduced the construction efficiency. Steel shear keys’ impact on structural behavior was limited when epoxy joints are used, compared to joints without shear keys. In addition, a two-dimensional finite element model (2D-FEM) was developed and validated to investigate the influence of load point position, concrete strength, number of prestressing strands, number of SR-TJs, and initial prestress on structural performance. The 2D-FEM analysis demonstrated that increasing the initial prestress and the cross-sectional area of the strands enhanced both the cracking resistance and the ultimate load capacity of the girders. The influence of concrete strength on the structure was found to be minor. The stress distribution was greatly influenced by the loading point location, potentially causing inclined cracks that altered the failure mode. When less longitudinal reinforcement was used in the segments, no splitting failure occurred near the joint. These findings provide valuable insights for optimizing joint design in Tri-Segment T-Girder bridges.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109430"},"PeriodicalIF":4.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Weld battering of thermite welds and flash butt welds based on statistical evaluations

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-24 DOI: 10.1016/j.engfailanal.2025.109457

Markus Loidolt, Stefan Marschnig

{"title":"Weld battering of thermite welds and flash butt welds based on statistical evaluations","authors":"Markus Loidolt, Stefan Marschnig","doi":"10.1016/j.engfailanal.2025.109457","DOIUrl":"10.1016/j.engfailanal.2025.109457","url":null,"abstract":"<div><div>Continuous welded rails are an improvement over bolted joints, but still some issues occur associated with welds. One of these issues, rail surface irregularities, is addressed in this paper. When a train passes the uneven rail surface, dynamic impact loads emerge. These loads increase the risk of weld breakage and cause ballast damage, resulting in significant long-term costs. There are two mechanisms driving weld irregularities: Initial irregularities caused by imperfect weld fabrication, and irregularities that grow over time due to the material hardness being adjusted by heating and cooling effects. The latter mechanism is called weld battering and differs for thermite and flash butt welds. A statistical evaluation based on 20 years of data and over 2000 welds yields that battering rates are 25 times higher for thermite welds. Further evaluations reveal that various track design features either amplify or attenuate weld battering. Track radii, steel grade, the passing vehicle collective, sleeper type, rail profile, the width of the extraneous material, the wear rate of the surrounding rail and the manufacturing quality are found to be influential features. The age of a weld and the daily load in gross tonnes have no significant influence. These results indicate that weld battering must be described as local wear and that dynamic loads are not the driving force.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109457"},"PeriodicalIF":4.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

RC T-beams with flexural strengthening in the negative moment region under different configurations of NSM CFRP rods

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-24 DOI: 10.1016/j.engfailanal.2025.109458

Yanuar Haryanto , Nanang Gunawan Wariyatno , Fu-Pei Hsiao , Hsuan-Teh Hu , Ay Lie Han , Laurencius Nugroho , Hioe Hartono

{"title":"RC T-beams with flexural strengthening in the negative moment region under different configurations of NSM CFRP rods","authors":"Yanuar Haryanto , Nanang Gunawan Wariyatno , Fu-Pei Hsiao , Hsuan-Teh Hu , Ay Lie Han , Laurencius Nugroho , Hioe Hartono","doi":"10.1016/j.engfailanal.2025.109458","DOIUrl":"10.1016/j.engfailanal.2025.109458","url":null,"abstract":"<div><div>This study employed a near-surface mounted (NSM) technique to enhance the flexural performance of reinforced concrete (RC) T-beams in the negative moment region, using carbon fiber reinforced polymer (CFRP) rods embedded at varying depths. An experimental investigation was conducted, supported by analytical calculations and finite element (FE) simulations, to validate the results. The experiments revealed that beams with half-embedded CFRP rods experienced partial debonding at significant crack locations, a problem potentially mitigated by fully embedded rods. Strengthening with NSM-CFRP rods increased cracking, yield, and ultimate loads by 10–21%, 36–38%, and 30–40%, respectively, compared to control beams, while also enhancing stiffness. However, these methods may have a twofold impact on the specimen by decreasing its ductility and energy absorption capacity. The analytical approach provided accurate and conservative predictions, with a coefficient of variation of 4.5%, while the FE model demonstrated high accuracy, achieving a coefficient of variation of 3.5% when compared to experimental flexural load capacity results.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109458"},"PeriodicalIF":4.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Removal notice to “Coupling effect of high temperature and fatigue loading on ballastless track concrete in geothermal tunnel” [Eng. Failure Anal. 167 (2025) 109060]

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-24 DOI: 10.1016/j.engfailanal.2025.109432

Jiaxin Wen , Huajian Li , Fali Huang , Zhiqiang Yang , Haoliang Dong , Zhen Wang , Zhonglai Yi

引用次数: 0

Progressive damage and failure analysis of CNT-reinforced laminated nanocomposite structures: A multiscale modeling framework

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-22 DOI: 10.1016/j.engfailanal.2025.109452

Panagiotis A. Antoniou , Konstantinos P. Stamoulis , Stelios K. Georgantzinos

{"title":"Progressive damage and failure analysis of CNT-reinforced laminated nanocomposite structures: A multiscale modeling framework","authors":"Panagiotis A. Antoniou , Konstantinos P. Stamoulis , Stelios K. Georgantzinos","doi":"10.1016/j.engfailanal.2025.109452","DOIUrl":"10.1016/j.engfailanal.2025.109452","url":null,"abstract":"<div><div>This article presents a Multiscale Modeling Framework for the prediction of the progressive damage and failure analysis of laminated composites structures reinforced with carbon nanotubes (CNTs). First, the modified Halpin-Tsai (H-T) model is employed to estimate the mechanical properties of CNT-reinforced matrix. The H-T equation is capable of distinguishing the difference between micro and nanoscale and accounting for factors such as CNT dispersion and curvature. To capture the CNT and surrounding polymer interactions at the microscale, the Young’s modulus of the isolated CNT is evaluated using the equivalent fiber technique. In addition, the Chamis equations are used to predict the stiffness of the nanocomposite lamina. Then, a set of six equations is developed to estimate the ultimate strength of the nanocomposite lamina based on the individual properties of its constituents, including fibers and the CNT-reinforced polymer matrix. Finally, the damage initiation criterion for Fiber-Reinforced Polymer Composites, based on Hashin’s theory and combined with the fracture energy approach is employed to predict the progressive damage and failure behavior of laminated nanocomposite structures, subjected to tensile loads. This analysis considers the effects of CNT critical factors and size. The predictions of the present Multiscale Modeling Framework are in very good agreement with experimental stress–strain data. It has been demonstrated that while the CNT inclusions can enhance the overall strength of nanocomposite laminae, the tensile strength of the nanocomposite beams is markedly influenced by the microstructural characteristics of CNTs, which significantly reduce the CNTs effectiveness in reinforcing Fiber-Reinforced Polymer Composites.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109452"},"PeriodicalIF":4.4,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Prediction of service life of friction damage of WC coating on hot roll descaling rolls based on modified Archchard theory

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-21 DOI: 10.1016/j.engfailanal.2025.109442

Kailiang Qiu , Lianghai Feng , Li Zhang , Zhenshan Zhang , Yongjun Feng , Zhiwen Xie

{"title":"Prediction of service life of friction damage of WC coating on hot roll descaling rolls based on modified Archchard theory","authors":"Kailiang Qiu , Lianghai Feng , Li Zhang , Zhenshan Zhang , Yongjun Feng , Zhiwen Xie","doi":"10.1016/j.engfailanal.2025.109442","DOIUrl":"10.1016/j.engfailanal.2025.109442","url":null,"abstract":"<div><div>The friction damage data of hot rolling descaling rollers is limited by small sample size and challenges in data collection, significantly impacting the evaluation of the surface cladding coating’s service performance and life. To effectively assess the impact of Ni-based WC45 coating on the friction damage and service life of descaling rollers, a prediction method based on a modified Archard theory was proposed. By integrating experiments with finite element simulations, the friction characteristics and service life of the Ni-based WC45 coating were investigated. The results indicate that the primary mode of friction damage in the Ni-based WC45 coating is abrasive wear. While increasing operating temperatures exacerbate friction damage, they simultaneously reduce the friction coefficient. WC particles within the coating are deposited between the surface and transition layers, contributing to its superior wear resistance. The wear depth profile of the coating follows a “low-high-low” pattern and asymptotically approaches zero. The accuracy of the wear depth prediction model for the Ni-based WC45 coating, developed using the modified Archard theory, exceeds 90%. Compared to other forms of service damage, friction damage has a negligible effect on service life, and the Ni-based WC45 coating demonstrates excellent friction damage protection. These findings provide a theoretical foundation for optimizing the performance of the Ni-based WC45 coating for descaling rollers and offer a reliable basis for the precise maintenance of hot rolling descaling rollers.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109442"},"PeriodicalIF":4.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Friction and wear failure mechanism analysis of QT600-3 ductile iron elevator traction sheave

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-21 DOI: 10.1016/j.engfailanal.2025.109414

Yueyang Jiang , Zhong Wen , Yongxian Chen , Chao Xiang , Shengqi Chao

{"title":"Friction and wear failure mechanism analysis of QT600-3 ductile iron elevator traction sheave","authors":"Yueyang Jiang , Zhong Wen , Yongxian Chen , Chao Xiang , Shengqi Chao","doi":"10.1016/j.engfailanal.2025.109414","DOIUrl":"10.1016/j.engfailanal.2025.109414","url":null,"abstract":"<div><div>Elevators play a significant role in the daily lives. The traction sheave is the primary component responsible for bearing the force within an elevator system. The elevator car is propelled through the friction generated between the steel wire rope and the groove of the traction sheave. Over time, Prolonged operation results in significant wear between the traction sheave and the steel wire rope. This paper adopts a multi-methodological approach, utilizing macro and micro morphology analysis, equivalent friction coefficient analysis, and cloth hardness testing to elucidate the underlying causes of traction sheave failure. Groove C exhibits the most severe wear, with a maximum wear depth exceeding that of the other grooves by 2.4 mm. Measurements indicate that the <span><math><mi>β</mi></math></span>angle of groove C is 101°and the <span><math><mi>γ</mi></math></span>angle is 11°, which are significantly below the specified requirements. Additionally, measurements of grooves A, B, D, and E reveal that their<span><math><mi>γ</mi></math></span>angles are all less than 35°, thus failing to meet the specified standards. The average hardness of the material is 208.9 HBW. The friction coefficient of groove C under loading and braking conditions is 0.23, while the friction coefficient under holding conditions is 2.11. The findings reveal that wear is the predominant factor contributing to the deterioration of the traction wheel. The surface of the worn rope groove is characterized by numerous abrasive particles, pits, cracks, scratches, and other forms of surface damage. The deterioration of surface quality and the emergence of uneven surface roughness after wear further exacerbate the progression of uneven wear. The hardness of the base material does not meet established standards. Finally, to extend the service life of the traction sheaves and prevent accidents, we propose several improvement recommendations.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109414"},"PeriodicalIF":4.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and numerical investigation on failure of PVC foam core tapered sandwich composites under four-point bending

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-21 DOI: 10.1016/j.engfailanal.2025.109450

Hamid Babaee Kashani , Mahmoud Shariati , Masoud Tahani , Pedram Zamani

{"title":"Experimental and numerical investigation on failure of PVC foam core tapered sandwich composites under four-point bending","authors":"Hamid Babaee Kashani , Mahmoud Shariati , Masoud Tahani , Pedram Zamani","doi":"10.1016/j.engfailanal.2025.109450","DOIUrl":"10.1016/j.engfailanal.2025.109450","url":null,"abstract":"<div><div>According to the application of tapered sandwich composites in wind turbine blade, it is important to study the influence of design parameters affecting on the strength, durability, and failure modes of these structures. In this way, the present research aims at investigating the influence of ramp-down area geometry of tapered sandwich composite on the static strength, fatigue response, and failure mode under four-point bending load. For this purpose, slopes of 11° (reference), 18°, and 45° were considered as geometrical factors, and distance of loading roller to tapered area and mid-span were considered as four-point loading factors. The extended finite element method (XFEM) was implemented to simulate crack growth behavior using the virtual crack closure technique (VCCT) in combination with the maximum tangential stress theory. Results showed that strength of tapered sandwich composites with slope of 18° in the ramp-down zone was 7.4% higher than that of the reference specimen, while, those having 1:1 slope resulted in 16.5% lower strength compared to reference specimen. It was found that distance of loading roller to tapered area and mid-span distance can significantly affect the failure mode and strength. Examination of crack propagation using experimental tests and XFEM revealed that, generally, the crack initiated under the loading roller, propagated into the foam core, changed its growth direction toward the tapered zone, and finally, led to debonding of the facesheets. Under high fatigue load levels, it was found that tapered design with slope angle of 18° increased the fatigue life more than twice of the life of reference specimen group.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109450"},"PeriodicalIF":4.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fragility analysis of cross-sea highway cable-stayed bridges under seismic-wind combined loading

IF 4.4 2区工程技术

Engineering Failure Analysis Pub Date : 2025-02-21 DOI: 10.1016/j.engfailanal.2025.109451

Yan Liang , Tanfang Zhao , Yingying Wei , Pinwu Guan

{"title":"Fragility analysis of cross-sea highway cable-stayed bridges under seismic-wind combined loading","authors":"Yan Liang , Tanfang Zhao , Yingying Wei , Pinwu Guan","doi":"10.1016/j.engfailanal.2025.109451","DOIUrl":"10.1016/j.engfailanal.2025.109451","url":null,"abstract":"<div><div>Cable-stayed bridges in seismic zones are inevitably exposed to strong winds and earthquakes throughout their service life. This study examines the fragility of cable-stayed bridges under the combined influence of earthquakes and wind, using the Hong Kong-Zhuhai-Macao Bridge as a case study. Utilizing the PEER database, 150 seismic motion records with Peak Ground Acceleration (PGA) ranging from 0.01 g to 1.0 g were generated, accounting for non-uniform seismic excitation. Pulsating wind speeds are simulated using the harmonic synthesis method.Design reference periods of 500 years and return periods of 10, 50, and 120 years for basic wind speeds are selected separately. Wind load time history curves are established and combined randomly with seismic motions to generate seismic-wind speed samples. Fragility curves for bridge components and systems are established through incremental dynamic analysis.The research findings indicate that in the presence of both earthquakes and wind, bridge towers and piers are primarily affected by seismic loads.The effect of wind on the amplification of cable fragility increases significantly with wind speed. However, an increase in seismic intensity reduces the impact of wind loads on cable fragility.Seismic action is the primary cause of damage to the cable-stayed bridge system in cases of low wind speeds.However, as wind speeds increase, slight and moderate damage states are primarily caused by seismic action, while extensive damage and complete destruction states are significantly influenced by both seismic and wind factors.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109451"},"PeriodicalIF":4.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0