98%
921
2 minutes
20
In this work, the finite element method (FEM) is used to investigate the propagation of laser-generated Rayleigh wave along the material surface at the quarter-arc transition surface under the thermoelastic regime, and to establish the relationship between the circular-arc radius and the time domain characteristics of reflected and transmitted Rayleigh waves. The simulation shows that the amplitude of the reflected Rayleigh wave decreases whereas the amplitude of the transmitted Rayleigh wave increases as the radius increases, which is significantly different from the well-studied interaction of Rayleigh waves with the perpendicular transition surface. By introducing the circular-arc defects which are easily formed in some engineering components during the material surface quenching, we find that the depth gauging of the surface circular-arc defects is more accurate in comparison to the surface rectangular defects based on the arrival time of the transmitted Rayleigh wave. This is further verified by the corresponding experimental results. These foundings are of practical values for detecting the depth of the arc defect quantitatively by the laser ultrasonic technique.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ultras.2020.106085 | DOI Listing |
Sci Adv
August 2025
Joint Quantum Institute, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA.
Instabilities, where small fluctuations seed the formation of large-scale structures, govern dynamics in a variety of fluid systems. The Rayleigh-Taylor instability (RTI), present from tabletop to astronomical scales, is an iconic example characterized by mushroom-shaped incursions appearing when immiscible fluids are forced together. Despite its ubiquity, RTI experiments are challenging; here, we report the observation of the RTI in an immiscible binary superfluid consisting of a two-component Bose-Einstein condensate.
View Article and Find Full Text PDFJ Acoust Soc Am
August 2025
State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
This paper presents a theoretical model for the scattering attenuation of Rayleigh waves propagating along the stress-free planar surface of a three-dimensional (3D) semi-infinite polycrystalline medium with single-phase, untextured, equiaxed grains and arbitrary symmetry. The model can explain the behavior of the Rayleigh wave scattering into Rayleigh and bulk waves, i.e.
View Article and Find Full Text PDFLab Chip
August 2025
Department of Chemical, Biological, and Materials Engineering, University of South Florida, Tampa, FL 33620, USA.
Characterizing extracellular vesicles (EVs) using mass spectrometry (MS) provides several advantages. The molecular compositions within EVs can be analyzed at very low concentrations and can also distinguish lipids and molecules with similar structures. However, there are some challenges when analyzing EVs directly using MS, mainly due to their variations in size and biological composition, as well as their tendency to form large clusters.
View Article and Find Full Text PDFJ Acoust Soc Am
August 2025
Electrical and Computer Engineering Department, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
Phonon mode normalizations derived in this paper are based on a consistent approach for normalizing Rayleigh waves. These Rayleigh waves are being used increasingly for nanoscale applications, including quantum information technology, and currently the literature is full of unnecessary approximate forms of these normalizations. The self-consistency of these derivations, for commonly used Rayleigh wave modes, is based on the second quantization procedure where the mechanical energy in the modes is equated with the energy of a phonon mode.
View Article and Find Full Text PDFOpt Express
February 2025
The interferometric Fiber Bragg Grating (FBG) hydrophone has wide applications in ocean acoustic detection and seismic wave monitoring. The interference signal from external sources is routed to the elements through the link fiber connecting the dry and wet ends, which is a critical bottleneck that limits system performance. This paper presents a comprehensive model for link fiber-induced spurious signals, which demonstrates the physical processes and signal characteristics of the Doppler effect and the Rayleigh scattering effect, illustrating how they interact to generate the link interference signal.
View Article and Find Full Text PDF