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Showing 1 to 17 of 17 for “"power ultrasound"”.
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The influence of power ultrasound on leather processing
The effects of ultrasound (38 kHz, 1.3 W cm2) on the dyeing, fatliquoring and tanning of leather have been investigated and the mechanisms whereby ultrasound influences these processes were elucidated. Compared with a conventional process, ultrasonic dyeing can either shorten the dyeing time by …
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Energy scalable systems for 2D and 3D low-power ultrasound beamforming
In traditional ultrasound imaging systems, bulky and power-intensive mainframes are used to process the high number of waveforms acquired in parallel from a large transducer array. The computational power of these systems scales linearly with transducer count. However, there exist applications …
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Applications of ultrasound in pharmaceutical processing and analytics.
… this research was to explore application of high power ultrasound in the slurry crystallisation and application of low power ultrasound (3.5 MHz) as process analytical technology (PAT) tool to understand pharmaceutical processing such as hot melt extrusion. The effect of high power ultrasound (20 …
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The design of high power ultrasonic transducers
… investigate the design and construction of high power ultrasound transducers as well as some of the effects of high power ultrasound. The two design approaches that are researched and applied are the equivalent circuit method and Finite Element Method (FEM). These methods are used in conjunction …
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Sonoelectrochemical synthesis of submicron metal powders
… alternating pulses of electric current and power ultrasound are applied to an electrochemical cell to create and suspend particles in the electrolyte. The pulsed technique largely separates the particle morphology defining physical action of electrochemistry and ultrasound. Despite the large …
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Development of positioning devices for MRI-guided high intensity focused ultrasound (HIFU) for abdominal, thyroid and brain, tumours
High intensity focused ultrasound (HIFU) is a promising technology for a variety of therapeutic applications. This concept initiated in 1942 by Lynn Zwemer [1]. HIFU has long been known as a minimal invasive or non-invasive procedure that destroys tissue through ablation. However, it is only in …
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Acoustic emulsions of liquid, near-critical carbon dioxide and water : application to synthetic chemistry through reaction engineering
… less successful due to its limited solvation power. Furthermore, the rates of reactions conducted in scCO2 tend to be slower than and their selectivities are comparable to those observed in hydrocarbon solvents. This research focused on development of water/carbon dioxide biphasic reaction …
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Design of Electromechanical Attachments for Improved Ultrasound Imaging Repeatability
Ultrasound imaging (or ultrasonography) is a common tool used for medical diagnostics. It has many advantages over other imaging modalities (such as MRI and CT) such as being more portable, less expensive, and lower power. Ultrasound imaging is emerging as a noninvasive diagnostic alternative in …
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Semi-supervised detection of industrial fouling using ultrasound
… the process, which is costly. Recently, high-power ultrasound has become a viable option to these methods. In ultrasonic cleaning ultrasound is projected into the equipment from the outside, which means that the equipment does not need to be halted to perform cleaning. While the cleaning …
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Fundamental research regarding the ultrasonic stirring effects on the microstructure of A356 castings
… acoustic streaming and propagation of ultrasound waves in media. However, the mechanism of how those effects happen are not fully understood and quantified. In this research, molten A356 alloy was treated with high power ultrasound at a frequency of 18 kHz, and then at relatively high …
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Ultrasound Assisted Processing of Solid State Pharmaceuticals. The application of ultrasonic energy in novel solid state pharmaceutical applications, including solvent free co-crystallisation (SFCC) and enhanced compressibility
… methods. A novel, solvent-free, high-power ultrasound (US) technique, for preparing co-crystals from binary systems, was chosen as the technology which could fulfil these aims. The application of this technology for solid state co-crystal preparation was explored for …
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Separation of solvents from selected biopolymeric matrixes and aqueous mixtures by ultrasound
… waves at different frequencies. First, power ultrasound was used to separate ethanol from an ethanol-water mixture, with a focus on prototype development and optimization of process parameters, including the initial ethanol concentration, carrier gas-flow rate, temperature, and mist …
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Design of a high intensity ultrasound dispersion cell
… the factors causing mechanical damage in a high power ultrasound environment, and to give recommendations for the production of an ultrasonic dispersion cell with a removable treatment vessel. The primary mechanism for causing this dispersion was cavitation: a void of air or vapour in a liquid …
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Management of wine aroma using biotechnical tools
… efficacy of the combination of AP-I with high power ultrasound. At the lowest energy applied ultrasound promoted AP-I activity, with no evident effect on enzyme degradation.
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Quantitative Evaluation of Recovery Methods for Listeria monocytogenes Applied to Stainless Steel
The ability of Listeria monocytogenes, to attach to various food contact surfaces such as stainless steel, polypropylene, and rubber compounds is well documented. The retention of these or other pathogenic bacteria on food contact surfaces increases the risk of transmission to food products. The …
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Application of novel processing technologies for salt reduction in meat products
… strategies: i) enhancement of salt diffusion by power ultrasound (US), ii) improvement of natural saltiness by high pressure processing (HPP) and iii) use of plasma technology as an alternative curing source. The first four chapters are focus on the use of US alone or in combination with salt …
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Novel ingredients and emerging processing technologies in the development of clean label, phosphate-reduced meat products
… the functional properties of AP and CSS using Power Ultrasound (US) technology Chapter 4). This investigated the effect of US treatment of 20 kHz, 250 W at different time intervals of 15 and 30 minutes on the techno-functional properties of AP and CSS, such as water and oil absorption capacity …