Optimizing ultrasound frequency in burst wave lithotripsy

2021 ◽  
Vol 150 (4) ◽  
pp. A352-A352
Author(s):  
Oleg A. Sapozhnikov ◽  
Michael R. Bailey
Keyword(s):  
Ultrasound Frequency

scholarly journals An Analysis of Acoustic Cavitation Thresholds of Water Based on the Incubation Time Criterion Approach

Fluids ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 134
Author(s):  
Ivan Smirnov ◽  
Natalia Mikhailova
Keyword(s):  
Incubation Time ◽  
Dynamic Strength ◽  
Acoustic Cavitation ◽  
Nucleation Theory ◽  
Classical Nucleation Theory ◽  
Accurate Estimation ◽  
Ultrasound Frequency ◽  
Time Criterion ◽  
Good Potential ◽  
Cavitation Threshold

Researchers are still working on the development of models that facilitate the accurate estimation of acoustic cavitation threshold. In this paper, we have analyzed the possibility of using the incubation time criterion to calculate the threshold of the onset of acoustic cavitation depending on the ultrasound frequency, hydrostatic pressure, and temperature of a liquid. This criterion has been successfully used by earlier studies to calculate the dynamic strength of solids and has recently been proposed in an adapted version for calculating the cavitation threshold. The analysis is carried out for various experimental data for water presented in the literature. Although the criterion assumes the use of macroparameters of a liquid, we also considered the possibility of taking into account the size of cavitation nuclei and its influence on the calculation result. We compared the results of cavitation threshold calculations done using the incubation time criterion of cavitation and the classical nucleation theory. Our results showed that the incubation time criterion more qualitatively models the results of experiments using only three parameters of the liquid. We then discussed a possible relationship between the parameters of the two approaches. The results of our study showed that the criterion under consideration has a good potential and can be conveniently used for applications where there are special requirements for ultrasound parameters, maximum negative pressure, and liquid temperature.

scholarly journals Sonochemical and Sonoelectrochemical Production of Energy Materials

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 284
Author(s):  
Faranak Foroughi ◽  
Jacob J. Lamb ◽  
Odne S. Burheim ◽  
Bruno G. Pollet
Keyword(s):  
Reaction Rates ◽  
Surface Cleaning ◽  
Energy Materials ◽  
Fast Reaction ◽  
Ultrasound Frequency ◽  
Production Of Hydrogen ◽  
Scientists And Engineers ◽  
Electrocatalyst Materials ◽  
Made In ◽  
Semiconductor Photocatalyst

Sonoelectrochemistry is the combination of ultrasound and electrochemistry which provides many advantages in electrochemistry, such as fast reaction rates, surface cleaning and activation, and increased mass transport at an electrode. Due to the advantages, some efforts have been made in order to benefit sonoelectrochemistry in the field of energy and environmental engineering. This review paper highlights the developed progress of the application of sonoelectrochemistry in the production of hydrogen, electrocatalyst materials and electrodes for fuel cells and semiconductor photocatalyst materials. This review also provides the experimental methods that are utilized in several sonoelectrochemical techniques, such as different set-ups generally used for the synthesis of energy-related materials. Different key parameters in the operation of sonoelectrochemical synthesis including ultrasonication time, ultrasound frequency and operation current have been also discussed. There are not many research articles on the sonoelectrochemical production of materials for supercapacitors and water electrolyzers which play crucial roles in the renewable energy industry. Therefore, at the end of this review, some articles which have reported the use of ultrasound for the production of electrocatalysts for supercapacitors and electrolyzers have been reviewed. The current review might be helpful for scientists and engineers who are interested in and working on sonoelectrochemistry and electrocatalyst synthesis for energy storage and energy conversion.

Ultrasound frequency effect on soybean protein: Acoustic field simulation, extraction rate and structure

LWT ◽  
2021 ◽  
Vol 145 ◽  
pp. 111320
Author(s):  
Yanhua Ding ◽  
Haile Ma ◽  
Ke Wang ◽  
S.M. Roknul Azam ◽  
Yaoyao Wang ◽  
...  
Keyword(s):  
Acoustic Field ◽  
Soybean Protein ◽  
Extraction Rate ◽  
Frequency Effect ◽  
Ultrasound Frequency ◽  
Field Simulation ◽  
Acoustic Field Simulation

ANALYSIS OF CAROTID ARTERIAL DOPPLER SIGNALS USING STFT AND WIGNER–VILLE DISTRIBUTION (WVD)

2009 ◽  
Vol 09 (01) ◽  
pp. 49-62
Author(s):  
MELLE SEDDIK AMINA ◽  
M. BEREKSI REGUIG FETHI
Keyword(s):  
Power Spectra ◽  
Doppler Imaging ◽  
Time Frequency ◽  
Ultrasound Frequency ◽  
Doppler Signals ◽  
Cross Terms ◽  
Noticeable Reduction ◽  
Doppler Power ◽  
Short Time

The study presented in this paper is concerned with the analysis of the ultrasound Doppler signal of the carotid arteries in the time-frequency domain using the short time Fourier transform (STFT) and the Wigner–Ville distribution (WVD). This study is carried out in order to investigate the behavior of the spectral broadening index (SBI) derived from spectra obtained using these methods. The variations in the shape of the Doppler power spectra as a function of time are presented in the form of sonograms in order to determine the degree of primitive carotid artery stenosis. The obtained results show a qualitative improvement in the appearance of the sonograms generated using the WVD over the STFT. However, despite this qualitative improvement the WVD suffers from some drawbacks: the presence of the cross terms which are primarily due to its quadratic nature. The application of the Choi–Williams distribution (CWD) in this analysis shows a noticeable reduction of these cross terms, improving therefore the quality of the sonograms. From these generated sonograms, the ultrasound frequency envelopes are extracted. The maximum and the mean frequencies in these envelopes are used to determine the SBI. The magnitude of the CWD-SBI is significantly greater than that of the STFT-SBI. In addition, there is a correlation between the SBIs obtained using the STFT and the CWD and the degree of severity of stenosis measured by 2D Doppler imaging.

scholarly journals Use of ultrasound for cleaning of components of historical vehicles in Technical Museum in Brno

2020 ◽  
Vol 64 (3) ◽  
pp. 79-86
Author(s):  
K. Rapouch ◽  
M. Mrázek
Keyword(s):  
Water Drop ◽  
Bath Temperature ◽  
Cleaning Process ◽  
Fuel System ◽  
Dissolved Metals ◽  
Cleaning Efficiency ◽  
Ultrasound Frequency ◽  
Aas Method ◽  
Ultrasound Effect

Abstract In the collections of Technical Museum in Brno, large number of historical vehicles is placed. During the operation, parts of their motors are being fouled. Frequently, they become even immobile (e. g. due to a fouled fuel system). In this case, the method using ultrasound with a suitable concentrate appears as the most suitable. In fact, ultrasound works also in inaccessible places with large efficiency. Not only the chosen solution influences the cleaning efficiency, but also parameters as time, bath temperature and ultrasound frequency. The cleaning process was evaluated according to the volume of removed dirt and by observing wettability change using the measuring of contact angle of a water drop. The ultrasound shock waves influence the surface to a certain extent also mechanically. That is why, the ultrasound effect on defects in the structure was observed. The aggressivity of cleaning concentrates was evaluated on the ground of determination of dissolved metals in the baths by ET AAS method.

scholarly journals Early diagnosis of skin cancer by ultrasound frequency analysis

2019 ◽  
Vol 20 (11) ◽  
pp. 153-168
Author(s):  
Shabnam Kia ◽  
Saeed Setayeshi ◽  
Majid Pouladian ◽  
Seyed Hossein Ardehali
Keyword(s):  
Skin Cancer ◽  
Early Diagnosis ◽  
Frequency Analysis ◽  
Ultrasound Frequency

Sonofragmentation: Effect of Ultrasound Frequency and Power on Particle Breakage

2016 ◽  
Vol 16 (11) ◽  
pp. 6167-6177 ◽  
Author(s):  
Jeroen Jordens ◽  
Tessa Appermont ◽  
Bjorn Gielen ◽  
Tom Van Gerven ◽  
Leen Braeken
Keyword(s):  
Particle Breakage ◽  
Ultrasound Frequency

Abstract P4-03-09: Malignant hyperechoic lesions in breast ultrasound - Frequency and characteristics

2016 ◽  
Author(s):  
J Camacho ◽  
E Horvath ◽  
MF Pizzolon ◽  
MA Pinochet ◽  
M Gallegos ◽  
...  
Keyword(s):  
Breast Ultrasound ◽  
Ultrasound Frequency
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