Results 231 to 240 of about 35,365 (254)

Optimum acoustic frequency for focused ultrasound surgery

Ultrasound in Medicine & Biology, 1994
A model is described that enables calculation of ultrasound lesioning rate (inverse of time to achieve a threshold lesion in the absence of thermal redistribution) as a function of acoustic frequency, tissue penetration depth, d, attenuation coefficient at specific frequency, mu, and power of dependence of attenuation on frequency, n.
openaire   +2 more sources

Squeezing of a Focused Acoustic Beam and Acoustic Microscopy of Anisotropic Media

Japanese Journal of Applied Physics, 1995
The concept of squeezing in quantum optics is applied to focused acoustic beam evaluation for the first time. Mathematical equivalence between coherent and squeezed states in quantum optics and angular spectra in various acoustical imaging schemes is derived and discussed.
openaire   +1 more source

Acoustic metamaterials with near-zero density effects for acoustic focusing

Journal of Vibration and Control
Acoustic focusing technology has demonstrated significant application prospects across multidisciplinary fields. Based on the principle of fractal self-similarity, this study proposes a novel fractal acoustic metamaterial. Calculations of equivalent acoustic parameters reveal that this structure exhibits near-zero density effects at frequencies of 2271 
He Chuan, Feng Feifei, Diao Lei, Tao Meng   +3 more
openaire   +1 more source

Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures

2013
In this thesis, wave propagation through acoustic materials with subwavelength slits structures is studied. Guided by the findings, acoustic wave focusing is achieved with a specific material design. By using a parameter retrieving method, an effective medium theory for a slab with periodic subwavelength cut-through slits is successfully derived.
openaire   +2 more sources

Acoustic focusing of microplastics in microchannels: A promising continuous collection approach

Sensors and Actuators B: Chemical, 2020
Yoshitake Akiyama, Hiroshi Moriwaki
exaly  

Observation of Ultrabroadband Acoustic Focusing Based on V‐Shaped Meta‐Atoms

Advanced Materials Technologies, 2020
, Shouqi Yuan, Hong-Xiang Sun
exaly  

Acoustic focusing of microplastics in microfabricated and steel tube devices: An experimental study on the effects from particle size and medium density

Separation and Purification Technology, 2022
Menake Piyasena
exaly  

Acoustic focusing by coiling up space

Applied Physics Letters, 2012
Yong Li, Xin-Ye Zou, Xuefeng Zhu
exaly  

High transmission acoustic focusing by impedance-matched acoustic meta-surfaces

Applied Physics Letters, 2016
Rasha AL JAHDALI
exaly  

Time-delayed acoustic sink for extreme sub-wavelength focusing

Mechanical Systems and Signal Processing, 2020
Jianyu Chen, Fuyin Ma, Jiu Hui Wu
exaly