High-efficiency diffraction modulation of light by strain-optic effect of piezoelectrically induced standing acoustic waves in bulk LiNbO3 crystal

1990 ◽  
Vol 3 (6) ◽  
pp. 193-195 ◽  
Author(s):  
Cs. Kuti ◽  
I. Turi ◽  
Li Yan ◽  
Chi H. Lee
Lab on a Chip ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 4064-4070 ◽  
Author(s):  
Haiwei Lu ◽  
Kirk Mutafopulos ◽  
John A. Heyman ◽  
Pascal Spink ◽  
Liang Shen ◽  
...  

We introduce a microfluidic device that uses traveling surface acoustic waves to lyse bacteria with high efficiency. This lysis method should be applicable to a wide range of bacteria species and can be modified to analyze individual bacteria cells.


2022 ◽  
Author(s):  
Jia-Hao Xu ◽  
Xing-Feng Zhu ◽  
Di-Chao Chen ◽  
Qi Wei ◽  
Da-Jian Wu

Abstract Broadband absorption of low-frequency sound waves via a deep subwavelength structure is of great and ongoing interest in research and engineering. Here, we numerically and experimentally present a design of a broadband low-frequency absorber based on an acoustic metaporous composite (AMC). The AMC absorber is constructed by embedding a single metamaterial resonator into a porous layer. The finite element simulations show that a high absorption (absorptance A > 0.8) can be achieved within a broad frequency range (from 290 Hz to 1074 Hz), while the thickness of AMC is 1/13 of the corresponding wavelength at 290 Hz. The broadband and high-efficiency performances of the absorber are attributed to the coupling between the two resonant absorptions and the trapped mode. A good agreement between the numerical simulation and experiment is obtained. Moreover, the high broadband absorption can be maintained under random incident acoustic waves. The proposed absorber provides potential applications in low-frequency noise reduction especially when limited space is demanded.


2015 ◽  
Vol 29 (28) ◽  
pp. 1550193 ◽  
Author(s):  
Hai-Long He ◽  
Shi-Liang Ou-Yang ◽  
Zhaojian He ◽  
Ke Deng ◽  
Heping Zhao

An acoustic waveguide based on the omnidirectional reflection of one-dimensional (1D) sonic crystal (sc) is designed to realize the flexible guiding of sound waves. Numerical simulations indicate that high-efficiency transmission can be achieved at arbitrary bending angle and over a wide frequency range. Moreover, flexible waveguide branches can also be easily constructed by introducing more crystal structures into the waveguides. Owing to its designing flexibility, this waveguide would be very useful in various integrated applications based on SCs.


1989 ◽  
Vol 41 (2) ◽  
pp. 243-255 ◽  
Author(s):  
Y. Nakamura ◽  
Joyanti Chutia

Reflection of ion-acoustic waves from the ion sheath in front of the separation grid in a double-plasma device has been investigated experimentally. The plasma potential φ of the source plasma was controlled relative to that of the target plasma. When eφ < κΤe, where Τe is the electron temperature, no reflection was observed. The reason for this is that ions are drifting towards the grid with the Bohm velocity, i.e. the ion-acoustic velocity. When eφ > κΤe the reflected wave consists of the ion-acoustic wave and the ion beam mode. The reflection coefficient for the ion-acoustic wave is about unity. This high efficiency is due to reflection of the ions themselves.


2012 ◽  
Vol 10 (3) ◽  
pp. 515-524 ◽  
Author(s):  
R. Saggini ◽  
A. Di Stefano ◽  
V. Galati ◽  
E. Panelli ◽  
M. Valeri ◽  
...  

The aim of the study was to show that the addition of extracorporeal shockwave therapy (ESWT) may significantly improve beneficial effects of eccentric training together with high efficiency focused acoustic waves for jumper's knee. We speculate that such an effect may be due to increased mechanotransduction effects on affected tissues. We assessed changes in pain and function in 42 male football players (aged 1834 years) after a treatment protocol consisting of I session with focused ESWT per week combined with 3 physiotherapy sessions per week, for 3 consecutive weeks. While treatment protocol was administered, ordinary activities, but not playing football were permitted. Their condition was evaluated before treatment, at the end of the rehabilitation period (3 weeks) and at 2 months, 4 months and 6 months after the end of treatment by clinical examination, instrumental analysis and VAS for pain assessment. Functional ability related to symptoms was assessed with VISA score. At the end of 2005,2006,2007,2008 and 2009 we carried out a telephone interview to investigate changes in pain and function and the efficacy of the treatment over time. Follow-up controls showed a reduction of average VAS score; after 6 months, tendons showed a structure closer to normal at ultrasonographic investigation. At the last telephone interview in 2009 many patients reported to consider ESWT as an effective treatment and described a significant improvement in their functional abilities, a significant reduction in drug consumption and 88% of subjects continued to play agonistic football. In conclusion, our results showed that, through the addition of ESWT, the effects of the classic vibration and eccentric training combination were improved compared to those found in our experience without ESWT. Although a control group was not included in the study (vibration and eccentric training without ESWT), results show a promising improvement and justify future prospective studies with a control group and more case series.


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