Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 8 of 8 for “"Ultrasonic fields"”.
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Ultrasonic fields in fluids: theoretical prediction using difference equations and three dimensional measurement using optical techniques
A technique for calculating bulk ultrasonic fields which uses implicit difference equations to evaluate the parabolic approximation to the Helmholtz equation is described. The parabolic approximation assumes that the field varies much faster in the transverse directions than in the direction of …
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Analysis of Power Deposition Patterns and Ultrasonic Phased Arrays for Localized Hyperthermia
… providing precision local hyperthermia by using ultrasonic phased arrays. A method for calculating ultrasonic fields and examples of field patterns produced by square ultrasonic sources are presented. Temperature distributions are calculated from power deposition patterns by using a finite …
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Hybrid optical and acoustic trapping
… technique, also termed as Sonotweezers, uses ultrasonic fields to manipulate particles and can manipulate large particles with ease and manipulate large numbers of polydisperse particles and agglomerations, although they currently lack the dexterity of optical tweezers. Combining these two …
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Multi-functional Holographic Acoustic Lenses for Modulating Low- to High-Intensity Focused Ultrasound
… related to biomedical-focused ultrasound and ultrasonic energy transfer. This dissertation also aims to investigate the dynamics of nonlinear acoustic beam shaping in engineered HALs. First, We will introduce 3D-printed metallic acoustic holographic mirrors for precise spatial manipulation of …
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Ultrasound assisted low-temperature synthesis of TiB2 and Al3Ti particulates in molten aluminum
… solid Ti powders can be avoided in the ultrasonic fields, allowing for the realization of a lower-temperature synthesis of Al<sub>3</sub>Ti at 700 °C.</p>
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Sonoptics : applications of light and sound in the context of biomedicine
… uptake can be caused through the incident ultrasonic pressure fi eld causing radial oscillations (cavitation) in the microbubbles, amongst other possibilities. However, the mechanisms responsible for any resultant increase in cell membrane permeability are not yet fully understood. This …
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Ultrasound field measurement and modelling for non-destructive testing
Ultrasonic Testing (UT) is one of most important methods of Non-destructive Testing (NDT) and ultrasonic waves can be generated and detected by means of numeric methods. This thesis focuses on piezoelectric transducers and Electromagnetic Acoustical Transducer (EMAT). For testing with piezoelectric …
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Size Effect in Polymeric Materials: the Origins and the Multi-physics Responses in Ultrasound Fields
… in these materials when subjected to HIFU fields. From top-down direction, experiments and finite element analysis, are also conducted in this research. An experimentally-validated finite element framework is built to study the mechanical response of shape memory polymers (SMPs) triggered …