An asymptotic method is applied to analyze the nonlinear oscillations of a gas bubble driven by a dual-frequency excitation. More specifically, the latter is considered as a combination of two neighboring, incommensurate frequencies and is treated as a nonstationary excitation. This implies that both amplitude and phase of the bubble response are slowly oscillating at the time scale of the frequency difference, thus leading to a regime of aperiodic oscillations. The approximate solution is successfully compared with numerical simulations and reveals the possibility of achieving larger bubble response amplitude compared to the monofrequency excitation for sufficiently high driving pressure and specific values of the frequency difference. The asymptotic theory captures the generation of additional spectral components coming from the nonlinear mixing of both driving frequencies. This mechanism is responsible for a global enhancement of the dual-frequency bubble response as it enables an energy transfer towards more efficient components which are successively tuned with the nonlinearly shifted resonance frequency of the bubble, thus limiting the saturation due to softening.
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http://dx.doi.org/10.1016/j.ultsonch.2017.03.028 | DOI Listing |
Ultrason Sonochem
January 2025
Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy; Polito(BIO)Med Lab, Politecnico di Torino, 10129 Turin, Italy. Electronic address:
In the context of molecular imaging, the present work explores an innovative platform made of lipid-coated nanocrystals as contrast-enhanced agent for both ultrasound imaging and sonoluminescence. At first, the dynamics of gas bubbles generation and cavitation under insonation with either pristine or lipid-coated nanocrystals (ZnO-Lip) are described, and the differences between the two colloidal systems are highlighted. These ZnO-Lip show an unprecedented ability to assist cavitation, which is reflected in enhanced sonoluminescent light emission with respect to the pristine nanocrystals or the pure water.
View Article and Find Full Text PDFSci Rep
January 2025
Beijing Gilface Technology Co., Ltd., Beijing, 100012, China.
In order to solve the problem of logging calibration without a free pipe in the process of acoustic variable density logging and the subjective problem of the free pipe calibration method, this paper studies an attenuation rate calibration method based on acoustic variable density logging. Using the developed acoustic wave probe response relationship device and the acoustic wave probe calibration device, the response consistency of the receiving probe of the acoustic wave instrument and the frequency of the transmitting probe can be calibrated in the laboratory, and the response consistency and frequency calibration coefficient can be obtained. Through this coefficient, the acoustic wave attenuation rate can be derived.
View Article and Find Full Text PDFJ Mater Chem B
January 2025
State Key Laboratory of Biopharmaceutical Preparation and Delivery, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Adjuvants can enhance an immunological response, which is an important part of vaccine research. Pickering bubbles have been a mega-hit for biomedical applications, including visualization and targeted drug delivery. However, there have been no studies on Pickering bubbles as an immunological adjuvant, and the special properties and structures of Pickering bubbles may play an important role in immunization.
View Article and Find Full Text PDFJ Ultrasound Med
January 2025
Department of Radiology, University of Michigan Health System, Ann Arbor, Michigan, USA.
Objective: Focused ultrasound has emerged as a precise and minimally invasive modality for effective cancer treatment. In this study, we propose a novel method that integrates the mechanical effects of focused ultrasound, known as histotripsy, with heating to enhance both the immediate and sustained cytotoxic effects on cancer cells.
Methods: Our investigation focused on VX2 cancer cells in suspension, examining five experimental groups: blank control, negative control, heating alone, histotripsy alone, and histotripsy with subsequent heating.
Medicine (Baltimore)
November 2024
College of Basic Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
Utilizing network pharmacology and molecular docking, we evaluated the possible pharmacological mechanism of Danggui Sini Decoction (DGSND) for treating erectile dysfunction (ED). DGSND's chemical components and targets were found utilizing the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Disease-related genes associated with ED were identified through GeneCards, OMIM, TTD, DrugBank, and DisGeNET databases.
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