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Agglomeration, Evaporation And Morphological Changes In Droplets With Nanosilica And Nanoalumina Suspensions In An Acoustic Field, Erick Tijerino
Agglomeration, Evaporation And Morphological Changes In Droplets With Nanosilica And Nanoalumina Suspensions In An Acoustic Field, Erick Tijerino
Electronic Theses and Dissertations
Acoustic levitation permits the study of droplet dynamics without the effects of surface interactions present in other techniques such as pendant droplet methods. Despite the complexities of the interactions of the acoustic field with the suspended droplet, acoustic levitation provides distinct advantages of controlling morphology of droplets with nanosuspensions post precipitation. Droplet morphology is controlled by vaporization, deformation and agglomeration of nanoparticles, and therefore their respective timescales are important to control the final shape. The balance of forces acting on the droplet, such as the acoustic pressure and surface tension, determine the geometry of the levitated droplet. Thus, the morphology …
A Laser Radar Employing Linearly Chirped Pulses From A Mode-Locked Laser For Long Range, Unambiguous, Sub-Millimeter Resolution Ranging And Velocimetry, Mohammad Umar Piracha
A Laser Radar Employing Linearly Chirped Pulses From A Mode-Locked Laser For Long Range, Unambiguous, Sub-Millimeter Resolution Ranging And Velocimetry, Mohammad Umar Piracha
Electronic Theses and Dissertations
Light detection and ranging (lidar) is used for various applications such as remote sensing, altimetry and imaging. In this talk, a linearly chirped pulse source is introduced that generates wavelength-swept pulses exhibiting ~6 nm optical bandwidth with > 20 km coherence length. The chirped pulses are used in an interferometric lidar setup to perform distance measurements with sub-millimeter resolution (using pulses that are a few meters long), at target distances > 10 km, with at least 25 dB signal-to-noise ratio at the receiver. A pulse repetition rate of 20 MHz provides fast update rates, while chirped pulse amplification allows easy amplification of …