Date of Graduation
12-2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Physics (PhD)
Degree Level
Graduate
Department
Physics
Advisor/Mentor
Yong Wang
Committee Member
Chen, Jingyi
Second Committee Member
Li, Jiali
Third Committee Member
Kumar, Pradeep
Keywords
bacteria, kinetics, lasers, motility, nanoparticles, photoluminescence
Abstract
This dissertation has two focus areas: nanoparticle nanowelding and bacteria motility in the presence of micrometer sized structures. There are two main projects for the nanoparticle nanowelding studies: “Real-time imaging of laser-induced nanowelding in solution” and “Two-color laser-induced nanostructure shape modulation.” For the real-time imaging project, I used a fluorescence microscope, a 405 nm laser, and various python packages to quantify the average size of nanowelded nanostructures as a function of time and found that the average nanostructure growth over time fit the parameters of A¯(t) ∝ c0(1−e−t/τ), where c0 represents the initial concentration of nanoparticles in the solution and τ is a parameter that depends on the power of my laser. For the two-color laser-induced nanostucture project, I used a combination of a 405 nm lase rand a 532 nm laser to see how nanostructure shape depends on the combination of laser wavelengths. Bacteria motility connects to my nanoparticle nanowelding projects through the research processes I used and the practical applications in various fields like energy generation and environmental remediation. I will discuss three projects related to bacterial motility in this paper: two simulation projects and one microscopy project that is still in progress. For the simulation projects, I looked at bacteria in the presence of micrometer-sized Tesla valves and bacteria in the presence of micro-pillars with different surface structures. For the microscopy project I started looking at what I will refer to as ‘potential wells’ to see how bacteria motility effects their ability to be trapped-in and escape from micrometer-sized well structures.
Citation
Rogers, A. (2023). Understanding the Kinetics of Laser-Induced Nanowelding of Nanoparticles and the Motility of Bacteria when Faced with Obstacles. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/5126