Results 31 to 40 of about 40,603 (292)
Research Progress and Development Trends of Acoustic Metamaterials
Molecules, 2021 Acoustic metamaterials are materials with artificially designed structures, which have characteristics that surpass the behavior of natural materials, such as negative refraction, anomalous Doppler effect, plane focusing, etc.
Hao Song +3 more
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Wave Propagation in an Inhomogeneous Medium [PDF]
, 1969 This paper is in two parts. In the first part we give a qualitative study of wave propagation in an inhomogeneous medium principally by geometrical optics and ray theory.
Blum, Joseph William
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Continuous-phase-transformation acoustic metasurface
Results in Physics, 2021 Acoustic metasurfaces are artificial structures, one of whose functions is to achieve plane wave focusing due to the phase gradient transformation of specific structural units. However, previous periodic acoustic metasurfaces for plane wave focusing have
Junfeng Chen, Jianlan Xie, Jianjun Liu
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Experiments on wave turbulence : the evolution and growth of second sound acoustic turbulence in superfluid 4He confirm self-similarity. [PDF]
, 2010 We report our experiments on the formation of second sound acoustic turbulence in superfluid 4He. The initial growth in spectral amplitude follows power laws that steepen rapidly with increasing harmonic number n, corresponding to a propagating front in ...
P V E McClintock +9 more
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M-Bonacci Zone Plates for Ultrasound Focusing
Sensors, 2019 In this work, we present a thorough analysis on M-bonacci zone plates for ultrasound focusing applications. These planar lenses are capable of providing bifocal focusing profiles with equal intensity in both foci and become very appealing for a wide ...
Sergio Pérez-López +2 more
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Linearly focused acoustic beams for acoustic microscopy
Electronics Letters, 1981 A linearly focused acoustic beam is investigated to be introduced into acoustic microscopy for characterising materials in the nonscanning version. The new acoustic beam enables us to detect acoustic anisotropies of materials to be measured successfully.
J. Kushibiki, A. Ohkubo, N. Chubachi
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Results in Optics, 2021 Experimental and simulation investigations on laser-induced acoustic wave propagation and the optical refraction effects by varying the focusing lens distance from the water-surface have been presented.
Xiaosong Shi +3 more
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Acoustic focusing and imaging via phononic crystal and acoustic metamaterials [PDF]
Journal of Applied Physics, 2022 The effective operation of certain electronic, medical, industrial, and testing equipment relies on high-quality focusing and imaging capability, which also plays a vital role in the field of wave physics. Therefore, continuously improving the resolution capacity is essential.
Fuyin Ma +3 more
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Menger fractal structure with negative refraction and sound tunnelling properties
Materials Research Express, 2019 We construct new quasi-three-dimensional fractal acoustic metamaterials based on adoption of the Menger structure, which offers extraordinary parameters such as double-negative properties and a near-zero density.
Yu Liu +6 more
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Intra-droplet acoustic particle focusing : simulations and experimental observations [PDF]
, 2018 The aim of this paper is to study resonance conditions for acoustic particle focusing inside droplets in two-phase microfluidic systems. A bulk acoustic wave microfluidic chip was designed and fabricated for focusing microparticles inside aqueous ...
Nilsson, Johan +4 more
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