Pub Date : 2025-01-23DOI: 10.1016/j.ultras.2025.107587
Jack Stevenson, Margaret Lucas
A new focussed ultrasound surgery (FUS) transducer for soft tissue ablation is proposed, with a miniaturised configuration that can be readily integrated with a surgical robot. The transducer fills a gap in FUS technology at this size, with capability for acoustic focus steering within a very simple transducer configuration. Miniaturisation is enabled by the incorporation of an acoustic Fresnel lens as the focussing element driven by a single piezoceramic disc. The transducer housing and Fresnel lens are made from photopolymer resins in a mask stereolithography (mSLA) printer and a microballoon filled epoxy backing layer is added to approximate an air backing. In this study, four versions of the miniature FUS transducer were fabricated and tested, each incorporating a different piezoceramic material: a soft PZT, a specialised composition for high intensity focused ultrasound, a low acoustic impedance porous PZT, and a lead free piezoceramic. It is shown that the FUS transducer containing the porous piezoceramic disc, which has lower piezoelectric and coupling coefficients than the other materials, achieves the highest focal zone intensity. Through finite element analysis (FEA) and experimental characterisations of the acoustic field, the FUS transducer is demonstrated to be capable of both creating and steering a focal intensity suitable for tissue ablation.
{"title":"A miniature FUS transducer based on an acoustic Fresnel lens for integration with a surgical robot","authors":"Jack Stevenson, Margaret Lucas","doi":"10.1016/j.ultras.2025.107587","DOIUrl":"10.1016/j.ultras.2025.107587","url":null,"abstract":"<div><div>A new focussed ultrasound surgery (FUS) transducer for soft tissue ablation is proposed, with a miniaturised configuration that can be readily integrated with a surgical robot. The transducer fills a gap in FUS technology at this size, with capability for acoustic focus steering within a very simple transducer configuration. Miniaturisation is enabled by the incorporation of an acoustic Fresnel lens as the focussing element driven by a single piezoceramic disc. The transducer housing and Fresnel lens are made from photopolymer resins in a mask stereolithography (mSLA) printer and a microballoon filled epoxy backing layer is added to approximate an air backing. In this study, four versions of the miniature FUS transducer were fabricated and tested, each incorporating a different piezoceramic material: a soft PZT, a specialised composition for high intensity focused ultrasound, a low acoustic impedance porous PZT, and a lead free piezoceramic. It is shown that the FUS transducer containing the porous piezoceramic disc, which has lower piezoelectric and coupling coefficients than the other materials, achieves the highest focal zone intensity. Through finite element analysis (FEA) and experimental characterisations of the acoustic field, the FUS transducer is demonstrated to be capable of both creating and steering a focal intensity suitable for tissue ablation.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107587"},"PeriodicalIF":3.8,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143068181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-22DOI: 10.1016/j.ultras.2025.107573
Nikunj Khetan , Jerome Mertz
Coherent Plane Wave Compounding (CPWC) is widely used for ultrasound imaging. This technique involves transmitting plane waves into a sample at different transmit angles and recording the resultant backscattered echo at different receive positions. The time-delayed signals from the different combinations of transmit angles and receive positions are then coherently summed to produce a beamformed image. Various techniques have been developed to characterize the quality of CPWC beamforming based on the measured coherence across the transmit or receive apertures. Here, we propose a more granular approach where the signals from every transmit/receive combination are separately evaluated using a quality metric based on their joint spatio-angular coherence. The signals are then individually weighted according to their measured Joint Coherence Factor (JCF) prior to being coherently summed. To facilitate the comparison of JCF beamforming compared to alternative techniques, we further propose a method of image display standardization based on contrast matching. We show results from tissue-mimicking phantoms and human soft-tissue imaging. Fine-grained JCF weighting is found to improve CPWC image quality compared to alternative approaches.
{"title":"Plane wave compounding with adaptive joint coherence factor weighting","authors":"Nikunj Khetan , Jerome Mertz","doi":"10.1016/j.ultras.2025.107573","DOIUrl":"10.1016/j.ultras.2025.107573","url":null,"abstract":"<div><div>Coherent Plane Wave Compounding (CPWC) is widely used for ultrasound imaging. This technique involves transmitting plane waves into a sample at different transmit angles and recording the resultant backscattered echo at different receive positions. The time-delayed signals from the different combinations of transmit angles and receive positions are then coherently summed to produce a beamformed image. Various techniques have been developed to characterize the quality of CPWC beamforming based on the measured coherence across the transmit or receive apertures. Here, we propose a more granular approach where the signals from every transmit/receive combination are separately evaluated using a quality metric based on their joint spatio-angular coherence. The signals are then individually weighted according to their measured Joint Coherence Factor (JCF) prior to being coherently summed. To facilitate the comparison of JCF beamforming compared to alternative techniques, we further propose a method of image display standardization based on contrast matching. We show results from tissue-mimicking phantoms and human soft-tissue imaging. Fine-grained JCF weighting is found to improve CPWC image quality compared to alternative approaches.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107573"},"PeriodicalIF":3.8,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143081190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-20DOI: 10.1016/j.ultras.2025.107581
Zenghua Liu , Jinlong Li , Yang Zheng , Cunfu He
Carbon steel and low alloy steel are pearlitic heat-resistant steels with a lamellar microstructure. There are good mechanical properties and are widely used in crucial components of high-temperature pressure. However, long-term service in high-temperature environments can easily lead to material degradation, including spheroidization, graphitization, and thermal aging. This study proposes a theoretical model of ultrasonic backscattering with a lamellar structure in pearlite areas. It analyzes the effects of different pearlite area ratios and interlamellar spacing on ultrasonic backscattering signals. A Voronoi diagram is used to constructs a two-dimensional finite element (FE) model of the lamellar structure, and the effects of different pearlite area ratio and interlamellar spacing on the backscattering signals are analyzed to verify the correctness of the theoretical model. By preparing spheroidization samples of various grades, the change values of pearlite area ratio and interlamellar spacing are measured. The backscattering signals of different spheroidization samples are collected through the ultrasonic testing experimental platform, and the root-mean-square (RMS) maximum values of the ultrasonic backscattering are extracted. The observed trend is consistent with the theoretical model, finite element method (FEM), and experimental. Compared with the experimental results, the model results have some errors, but can be used to evaluate the performance degradation of metallic materials with lamellar pearlite structure.
{"title":"Ultrasonic backscattering model of lamellar duplex phase microstructures in polycrystalline materials","authors":"Zenghua Liu , Jinlong Li , Yang Zheng , Cunfu He","doi":"10.1016/j.ultras.2025.107581","DOIUrl":"10.1016/j.ultras.2025.107581","url":null,"abstract":"<div><div>Carbon steel and low alloy steel are pearlitic heat-resistant steels with a lamellar microstructure. There are good mechanical properties and are widely used in crucial components of high-temperature pressure. However, long-term service in high-temperature environments can easily lead to material degradation, including spheroidization, graphitization, and thermal aging. This study proposes a theoretical model of ultrasonic backscattering with a lamellar structure in pearlite areas. It analyzes the effects of different pearlite area ratios and interlamellar spacing on ultrasonic backscattering signals. A Voronoi diagram is used to constructs a two-dimensional finite element (FE) model of the lamellar structure, and the effects of different pearlite area ratio and interlamellar spacing on the backscattering signals are analyzed to verify the correctness of the theoretical model. By preparing spheroidization samples of various grades, the change values of pearlite area ratio and interlamellar spacing are measured. The backscattering signals of different spheroidization samples are collected through the ultrasonic testing experimental platform, and the root-mean-square (RMS) maximum values of the ultrasonic backscattering are extracted. The observed trend is consistent with the theoretical model, finite element method (FEM), and experimental. Compared with the experimental results, the model results have some errors, but can be used to evaluate the performance degradation of metallic materials with lamellar pearlite structure.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107581"},"PeriodicalIF":3.8,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-20DOI: 10.1016/j.ultras.2025.107582
Bin Xu , Yun Zou , Gaofeng Sha , Liang Yang , Guixi Cai , Yang Li
In recent years, the widespread application of laser ultrasonic (LU) devices for obtaining internal material information has been observed. However, this approach demands a significant amount of time to acquire complete wavefield data. Hence, there is a necessity to reduce the acquisition time. In this work, we propose a method based on physics-informed neural networks to decrease the required sampling measurements. We utilize sparse sampling of full experimental data as input data to reconstruct complete wavefield data. Specifically, we employ physics-informed neural networks to learn the propagation characteristics from the sparsely sampled data and partition the complete grid to reconstruct the full wavefield. We achieved 95% reconstruction accuracy using four hundredth of the total measurements. The proposed method can be utilized not only for sparse wavefield reconstruction in LU testing but also for other wavefield reconstructions, such as those required in online monitoring systems.
{"title":"Sparse wavefield reconstruction based on Physics-Informed neural networks","authors":"Bin Xu , Yun Zou , Gaofeng Sha , Liang Yang , Guixi Cai , Yang Li","doi":"10.1016/j.ultras.2025.107582","DOIUrl":"10.1016/j.ultras.2025.107582","url":null,"abstract":"<div><div>In recent years, the widespread application of laser ultrasonic (LU) devices for obtaining internal material information has been observed. However, this approach demands a significant amount of time to acquire complete wavefield data. Hence, there is a necessity to reduce the acquisition time. In this work, we propose a method based on physics-informed neural networks to decrease the required sampling measurements. We utilize sparse sampling of full experimental data as input data to reconstruct complete wavefield data. Specifically, we employ physics-informed neural networks to learn the propagation characteristics from the sparsely sampled data and partition the complete grid to reconstruct the full wavefield. We achieved 95% reconstruction accuracy using four hundredth of the total measurements. The proposed method can be utilized not only for sparse wavefield reconstruction in LU testing but also for other wavefield reconstructions, such as those required in online monitoring systems.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107582"},"PeriodicalIF":3.8,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-20DOI: 10.1016/j.ultras.2025.107574
Lars Emil Haslund , Alexander Cuculiza Henriksen , Billy Yat Shun Yiu , Ali Salari , Marie Sand Traberg , Lasse Thurmann Jørgensen , Borislav Gueorguiev Tomov , Michael Bachmann Nielsen , Jørgen Arendt Jensen
Non-invasive estimation of pressure differences using 2D synthetic aperture ultrasound imaging offers a precise, low-cost, and risk-free diagnostic tool. Unlike invasive techniques, this preserves natural blood flow and avoids the limitations of devices that occupy lumen space. This paper evaluates a previously published estimator, modified to incorporate Singular Value Decomposition (SVD) echo-cancellation, using data from ten healthy volunteers and one patient. It is hypothesized that the estimator will enable precise pressure differences from the common carotid artery with a coefficient of variation of approximately 10% over a 10-second data acquisition period. Here, precision is essential to demonstrate the method’s consistency and its ability to differentiate between healthy and diseased arteries at the earliest possible stage. Data are acquired using a GE-9L-D, 5.2 MHz linear transducer connected to a Vantage 256 research scanner. The estimator was applied to the left common carotid artery of ten healthy volunteers, with precision being evaluated over the recorded heart cycles by using the coefficient of variation. Eight out of ten individuals showed precision below 10%, whereas two individuals showed precision above 20%. The best precision was attained by subject_03 with a coefficient of variation of 4.64% (16.1 Pa) and the worst precision was attained by subject 09 with a coefficient of variation of 23.3% (30.2 Pa). The average range of pressure differences across volunteers (from maximum positive to maximum negative pressure difference) was 297 Pa when measured across a 14 mm streamline. The corresponding average coefficient of variation was found to be 9.95% (24.6 Pa). A comparison of peak systolic velocities between the experimental scanner and the reference scanner demonstrates a strong positive linear correlation (R = 0.76). The corresponding slope of the linear best fit is 0.95, indicating that the relationship between the two scanners is close to a one-to-one match, with the experimental scanner’s measurements being slightly less than those of the reference scanner. Finally, data attained from a single patient example shows pressure differences ranging from −61.81 Pa to 1240.82 Pa with blood velocities as high as 1.73 m/s, which is significantly higher than seen in any of the healthy volunteers, supporting the likelihood of differentiating between stenosis grades in future studies. While this study is limited to 10 healthy volunteers and one patient, a different study design is needed to quantify the severity of stenosis and correlate it with pressure differences.
{"title":"Precision of in vivo pressure gradient estimations using synthetic aperture ultrasound","authors":"Lars Emil Haslund , Alexander Cuculiza Henriksen , Billy Yat Shun Yiu , Ali Salari , Marie Sand Traberg , Lasse Thurmann Jørgensen , Borislav Gueorguiev Tomov , Michael Bachmann Nielsen , Jørgen Arendt Jensen","doi":"10.1016/j.ultras.2025.107574","DOIUrl":"10.1016/j.ultras.2025.107574","url":null,"abstract":"<div><div>Non-invasive estimation of pressure differences using 2D synthetic aperture ultrasound imaging offers a precise, low-cost, and risk-free diagnostic tool. Unlike invasive techniques, this preserves natural blood flow and avoids the limitations of devices that occupy lumen space. This paper evaluates a previously published estimator, modified to incorporate Singular Value Decomposition (SVD) echo-cancellation, using data from ten healthy volunteers and one patient. It is hypothesized that the estimator will enable precise pressure differences from the common carotid artery with a coefficient of variation of approximately 10% over a 10-second data acquisition period. Here, precision is essential to demonstrate the method’s consistency and its ability to differentiate between healthy and diseased arteries at the earliest possible stage. Data are acquired using a GE-9L-D, 5.2 MHz linear transducer connected to a Vantage 256 research scanner. The estimator was applied to the left common carotid artery of ten healthy volunteers, with precision being evaluated over the recorded heart cycles by using the coefficient of variation. Eight out of ten individuals showed precision below 10%, whereas two individuals showed precision above 20%. The best precision was attained by subject_03 with a coefficient of variation of 4.64% (16.1 Pa) and the worst precision was attained by subject 09 with a coefficient of variation of 23.3% (30.2 Pa). The average range of pressure differences across volunteers (from maximum positive to maximum negative pressure difference) was 297 Pa when measured across a 14 mm streamline. The corresponding average coefficient of variation was found to be 9.95% (24.6 Pa). A comparison of peak systolic velocities between the experimental scanner and the reference scanner demonstrates a strong positive linear correlation (R<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> = 0.76). The corresponding slope of the linear best fit is 0.95, indicating that the relationship between the two scanners is close to a one-to-one match, with the experimental scanner’s measurements being slightly less than those of the reference scanner. Finally, data attained from a single patient example shows pressure differences ranging from −61.81 Pa to 1240.82 Pa with blood velocities as high as 1.73 m/s, which is significantly higher than seen in any of the healthy volunteers, supporting the likelihood of differentiating between stenosis grades in future studies. While this study is limited to 10 healthy volunteers and one patient, a different study design is needed to quantify the severity of stenosis and correlate it with pressure differences.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107574"},"PeriodicalIF":3.8,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Steel precision matching parts are widely used in aerospace and automobiles. In order to ensure the stability of the system, the matching parts’ mating surfaces, such as inner holes and outer shafts, are required to achieve nano-surface roughness and submicron-shape accuracy. Diamond-cutting technology is generally used for ultra-precision machining processes. However, it is not suitable for machining steel due to the active chemical reactions. Ultrasonic elliptical vibration cutting technology can significantly reduce the cutting heat to suppress the chemical wear of diamond tools. Consequently, this study proposes a novel simple theory-simulation design method for an ultrasonic elliptical vibration boring (UEVB) device. The device works in two six-order bending vibration modes, generating an elliptical tool motion in the plane determined by the nominal cutting direction and the cutting depth direction. Through the impedance test, frequency sweep test, and amplitude test, the test results of the device match well with the simulation results. The experimental results of cutting S136 steel show that the UEVB technology suppresses system chatter by 10 % and reduces surface roughness Ra by 72 % compared with common boring. Additionally, the tool has much light wear and the machined surface roughness is Ra 11.3 nm, which realizes the ultra-precision cutting of steel by diamond tools. Furthermore, the roundness of the processed hole, with a diameter of 30 mm, reaches 0.473 μm, which is significantly better than the highest standard grade G1 (0.5 μm). These results verify the feasibility of the proposed method.
{"title":"A novel design for double-bending elliptical vibration boring device and its performance evaluation","authors":"Yunxiang Zheng, Cheng Hu, Mao Wang, Zongpu Wu, Jianguo Zhang, Jianfeng Xu","doi":"10.1016/j.ultras.2025.107584","DOIUrl":"10.1016/j.ultras.2025.107584","url":null,"abstract":"<div><div>Steel precision matching parts are widely used in aerospace and automobiles. In order to ensure the stability of the system, the matching parts’ mating surfaces, such as inner holes and outer shafts, are required to achieve nano-surface roughness and submicron-shape accuracy. Diamond-cutting technology is generally used for ultra-precision machining processes. However, it is not suitable for machining steel due to the active chemical reactions. Ultrasonic elliptical vibration cutting technology can significantly reduce the cutting heat to suppress the chemical wear of diamond tools. Consequently, this study proposes a novel simple theory-simulation design method for an ultrasonic elliptical vibration boring (UEVB) device. The device works in two six-order bending vibration modes, generating an elliptical tool motion in the plane determined by the nominal cutting direction and the cutting depth direction. Through the impedance test, frequency sweep test, and amplitude test, the test results of the device match well with the simulation results. The experimental results of cutting S136 steel show that the UEVB technology suppresses system chatter by 10 % and reduces surface roughness Ra by 72 % compared with common boring. Additionally, the tool has much light wear and the machined surface roughness is Ra 11.3 nm, which realizes the ultra-precision cutting of steel by diamond tools. Furthermore, the roundness of the processed hole, with a diameter of 30 mm, reaches 0.473 μm, which is significantly better than the highest standard grade G1 (0.5 μm). These results verify the feasibility of the proposed method.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107584"},"PeriodicalIF":3.8,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143029396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Microwave surface and Lamb waves in a multilayered piezoelectric “Al-IDT/(Al0.72Sc0.28)N/(001)[110] diamond” structure designed as a SAW resonator were studied using both the experimental and modeling methods. In this structure, it is possible to generate Rayleigh, surface horizontal (SHn) and Lamb waves simultaneously. The successful excitation of Lamb waves at operating frequencies up to 20 GHz has been obtained. We have developed a method for identifying mode types based on an analysis of the elastic displacement fields and the frequency dependences of the dispersive phase velocities of each wave, as the frequency increases. The experimental data on the frequency response is in close agreement with the calculated values. The influence of Pt film deposition on the shifts in the resonant frequency of Lamb wave modes has been studied in detail. Since the Pt film was deposited on the free surface of a diamond substrate, shifts in the resonant frequency of Rayleigh-type waves are absent, as expected. This serves as an additional indication to distinguish these types of waves from others. The effect of film deposition on the frequency response of Lamb waves could be taken into account when designing acoustoelectronic sensors that use this type of wave as an operational mode.
{"title":"Microwave Surface and Lamb Waves in a Thin Diamond Plate: Experimental and Theoretical Investigation","authors":"B.P. Sorokin , D.V. Yashin , N.O. Asafiev , S.I. Burkov , M.S. Kuznetsov , N.V. Luparev , A.V. Golovanov","doi":"10.1016/j.ultras.2025.107575","DOIUrl":"10.1016/j.ultras.2025.107575","url":null,"abstract":"<div><div>Microwave surface and Lamb waves in a multilayered piezoelectric “Al-IDT/(Al<sub>0.72</sub>Sc<sub>0.28</sub>)N/(001)[110] diamond” structure designed as a SAW resonator were studied using both the experimental and modeling methods. In this structure, it is possible to generate Rayleigh, surface horizontal (SH<em><sub>n</sub></em>) and Lamb waves simultaneously. The successful excitation of Lamb waves at operating frequencies up to 20 GHz has been obtained. We have developed a method for identifying mode types based on an analysis of the elastic displacement fields and the frequency dependences of the dispersive phase velocities of each wave, as the frequency increases. The experimental data on the frequency response is in close agreement with the calculated values. The influence of Pt film deposition on the shifts in the resonant frequency of Lamb wave modes has been studied in detail. Since the Pt film was deposited on the free surface of a diamond substrate, shifts in the resonant frequency of Rayleigh-type waves are absent, as expected. This serves as an additional indication to distinguish these types of waves from others. The effect of film deposition on the frequency response of Lamb waves could be taken into account when designing acoustoelectronic sensors that use this type of wave as an operational mode.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107575"},"PeriodicalIF":3.8,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-15DOI: 10.1016/j.ultras.2025.107570
Thilhara Tennakoon , Tsz Wai Lai , Ka Chung Chan , Chun-Ho Liu , Randolph Chi Kin Leung , Christopher Yu Hang Chao , Sau Chung Fu
SAW (surface acoustic wave)-based microfluidics is fast becoming a recognised method for isolating and concentrating particles given its capacity for safe and label-free particle manipulation. However, widespread adoption of acoustofluidics for clinical and industrial applications is hindered by its limited capability handling submicron particles. Smaller particles, which are primarily influenced by the acoustic streaming effect, can be captured and enriched by streaming-induced vortices. This study investigated the role of microchannel cross-sectional geometry on the streaming patterns in an acoustically actuated volume and the behaviour of particles in it, in an effort to address the size limitation. Different regimes of particle trapping behaviour were observed and identified, and its dynamics explained using the competing outward centrifugal and inward inertial lift forces. These observations led to a proposed model of particle behavior in a vortex. The study found sloped sidewalls intensify streaming flows and concentration effect. Additionally, the individual vortices were observed becoming more/less affinitive to particles of a certain size, i.e. particles of different sizes were observed settling in distinct streaming vortices. This type of enhanced size-selective capturing behaviour can enable enrichment and binary separation of submicron particle mixtures, with a greater yield and purity than conventional rectangular microchannels.
{"title":"Leveraging microchannel cross-sectional geometry for acoustophoretic manipulation of submicron particles","authors":"Thilhara Tennakoon , Tsz Wai Lai , Ka Chung Chan , Chun-Ho Liu , Randolph Chi Kin Leung , Christopher Yu Hang Chao , Sau Chung Fu","doi":"10.1016/j.ultras.2025.107570","DOIUrl":"10.1016/j.ultras.2025.107570","url":null,"abstract":"<div><div>SAW (surface acoustic wave)-based microfluidics is fast becoming a recognised method for isolating and concentrating particles given its capacity for safe and label-free particle manipulation. However, widespread adoption of acoustofluidics for clinical and industrial applications is hindered by its limited capability handling submicron particles. Smaller particles, which are primarily influenced by the acoustic streaming effect, can be captured and enriched by streaming-induced vortices. This study investigated the role of microchannel cross-sectional geometry on the streaming patterns in an acoustically actuated volume and the behaviour of particles in it, in an effort to address the size limitation. Different regimes of particle trapping behaviour were observed and identified, and its dynamics explained using the competing outward centrifugal and inward inertial lift forces. These observations led to a proposed model of particle behavior in a vortex. The study found sloped sidewalls intensify streaming flows and concentration effect. Additionally, the individual vortices were observed becoming more/less affinitive to particles of a certain size, i.e. particles of different sizes were observed settling in distinct streaming vortices. This type of enhanced size-selective capturing behaviour can enable enrichment and binary separation of submicron particle mixtures, with a greater yield and purity than conventional rectangular microchannels.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107570"},"PeriodicalIF":3.8,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-15DOI: 10.1016/j.ultras.2025.107569
Jingwen Ding , Yiheng Li , Yang Jiao , Ninghao Wang , Yaoyao Cui
Shear Wave Elastography (SWE) is an imaging technique that detects shear waves generated by tissue excited by Acoustic Radiation Force (ARF), and characterizes the mechanical properties of soft tissue by analyzing the propagation velocity of shear wave. ARF induces a change in energy density through the nonlinear propagation of ultrasound waves, which drives the tissue to generate shear waves. However, the amplitude of shear waves generated by ARF is weak, and the shear waves are strongly attenuated in vivo. Furthermore, the shear waves are usually drowned out by noise at deep locations, which presents a challenge in the detection of shear waves and low signal-to-noise ratios. In this paper, we investigate the feasibility of applying the Chirp coded signal for shear wave excitation (Chirp-SWE) in ARF-based shear wave elastography. The use of Chirp coded excitation of push waveforms was employed to enhance the action of ARF, thereby effectively exciting shear waves. Comparative experiments were carried out with conventional sine long pulses (SWE) and the Barker coded signal (Barker-SWE). The analysis of theoretical and simulation results revealed that Chirp-SWE could increase the excitation energy by approximately 10% compared to conventional SWE and Barker-SWE. The results of the elastic phantom experiments demonstrated that the average peak axial particle velocity obtained by Chirp-SWE was approximately 30%–50% higher, which facilitated the formation of a more stable shear wave. Additionally, it exhibited a higher signal-to-noise ratio during elasticity measurements. The in vitro liver experiments further validated the feasibility of implementing Chirp-SWE in tissues. The results demonstrated the feasibility and advantages of Chirp coded excitation of push waveforms in improving shear wave elastography results. It is expected that this will enhance the accuracy and robustness of soft tissue elastography.
{"title":"A method of enhanced shear wave elastography based on Chirp coded excitation","authors":"Jingwen Ding , Yiheng Li , Yang Jiao , Ninghao Wang , Yaoyao Cui","doi":"10.1016/j.ultras.2025.107569","DOIUrl":"10.1016/j.ultras.2025.107569","url":null,"abstract":"<div><div>Shear Wave Elastography (SWE) is an imaging technique that detects shear waves generated by tissue excited by Acoustic Radiation Force (ARF), and characterizes the mechanical properties of soft tissue by analyzing the propagation velocity of shear wave. ARF induces a change in energy density through the nonlinear propagation of ultrasound waves, which drives the tissue to generate shear waves. However, the amplitude of shear waves generated by ARF is weak, and the shear waves are strongly attenuated in vivo. Furthermore, the shear waves are usually drowned out by noise at deep locations, which presents a challenge in the detection of shear waves and low signal-to-noise ratios. In this paper, we investigate the feasibility of applying the Chirp coded signal for shear wave excitation (Chirp-SWE) in ARF-based shear wave elastography. The use of Chirp coded excitation of push waveforms was employed to enhance the action of ARF, thereby effectively exciting shear waves. Comparative experiments were carried out with conventional sine long pulses (SWE) and the Barker coded signal (Barker-SWE). The analysis of theoretical and simulation results revealed that Chirp-SWE could increase the excitation energy by approximately 10% compared to conventional SWE and Barker-SWE. The results of the elastic phantom experiments demonstrated that the average peak axial particle velocity obtained by Chirp-SWE was approximately 30%–50% higher, which facilitated the formation of a more stable shear wave. Additionally, it exhibited a higher signal-to-noise ratio during elasticity measurements. The in vitro liver experiments further validated the feasibility of implementing Chirp-SWE in tissues. The results demonstrated the feasibility and advantages of Chirp coded excitation of push waveforms in improving shear wave elastography results. It is expected that this will enhance the accuracy and robustness of soft tissue elastography.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107569"},"PeriodicalIF":3.8,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143012610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-15DOI: 10.1016/j.ultras.2025.107571
Jakub Spytek , Daniel A. Kiefer , Ros Kiri Ing , Claire Prada , Jérôme Grando , Julien de Rosny
Detecting surface contamination on thin thermoformed polymer plates is a critical issue for various industrial applications. Lamb waves offer a promising solution, though their effectiveness is challenged by the strong attenuation and anisotropy of the polymer plates. This issue is addressed in the context of a calcium carbonate (CaCO) layer deposited on a polypropylene (PP) plate. First, the viscoelastic properties of the PP material are determined using a genetic algorithm inversion of data measured with a scanning laser vibrometer. Second, using a bi-layer plate model, the elastic properties and thickness of the CaCO layer are estimated. Based on the model, the sensitivity analysis is performed, demonstrating considerable effectiveness of the A1 Lamb mode in detecting thin layers of CaCO compared to Lamb modes A0 and S0. Finally, a direct application of this work is illustrated through in-situ monitoring of CaCO contaminants using a straightforward inter-transducer measurement.
{"title":"Sensitivity of Lamb waves in viscoelastic polymer plates to surface contamination","authors":"Jakub Spytek , Daniel A. Kiefer , Ros Kiri Ing , Claire Prada , Jérôme Grando , Julien de Rosny","doi":"10.1016/j.ultras.2025.107571","DOIUrl":"10.1016/j.ultras.2025.107571","url":null,"abstract":"<div><div>Detecting surface contamination on thin thermoformed polymer plates is a critical issue for various industrial applications. Lamb waves offer a promising solution, though their effectiveness is challenged by the strong attenuation and anisotropy of the polymer plates. This issue is addressed in the context of a calcium carbonate (CaCO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>) layer deposited on a polypropylene (PP) plate. First, the viscoelastic properties of the PP material are determined using a genetic algorithm inversion of data measured with a scanning laser vibrometer. Second, using a bi-layer plate model, the elastic properties and thickness of the CaCO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> layer are estimated. Based on the model, the sensitivity analysis is performed, demonstrating considerable effectiveness of the A1 Lamb mode in detecting thin layers of CaCO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> compared to Lamb modes A0 and S0. Finally, a direct application of this work is illustrated through in-situ monitoring of CaCO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> contaminants using a straightforward inter-transducer measurement.</div></div>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"149 ","pages":"Article 107571"},"PeriodicalIF":3.8,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143012620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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