Undergraduate Research Profiles
Undergraduate Student: Class of 2017
Majors: Physics and Mathematics
Hometown: Otego, NY
Awards: National Merit Scholar Commended Student, Dean's List
Research: Material Sciences, Physical Chemistry
Research Advisors: Binhua Lin, Stuart A. Rice
During my time here at UChicago, I had my first research experience in a lab that I have had the pleasure to remain continuously and deeply involved in since the middle of my 2nd year. Winter quarter of that year I joined the lab of Dr. Binhua Lin, Senior Scientist at Argonne National Laboratory, and Dr. Stuart Rice, Professor Emeritus in the Chemistry Department. Our lab works with colloidal micro- and nanoparticles, and I specifically work with gold nanoparticles. These are 5nm diameter uniform spherical composites of gold atoms, which are then covered with various hydrophobic thiol ligands that allow the particles to have complex interactions with each other that other un-ligate colloidal particles do not.
The first project I was involved in for this lab focused on studying the mechanical properties of gold nanoparticles when self-assembled into monolayer films on the air-water interface. We can deposit a solution of these ligated gold nanoparticles on to a flat water surface, and the hydrophobic ligands will drive the particles to remain on the surface and form into close-packed two-dimensional hexagonal lattices. By compressing these films and studying the corresponding pressure response, we could then extract film properties such as its two-dimensional elastic moduli. We studied these properties as we varied parameters such as ligand concentration and ligand molecule length. Mechanical characterizations like these allow these nanoparticle films to be compared to other monolayer films, such as lipid monolayers prominently used in biological sciences, with the long-term goal of determining how nanoparticle films could play a role in diverse fields such as biotechnology.
The summer after my 2nd year I stayed on campus to continue work in this lab. Over the summer, I became more focused on the structure of these nanoparticle films, which were then explored using electron microscopy. I learned how to use both a transmission electron microscope (TEM) and a scanning electron microscope (SEM), which both provide images on the nanometer scale of the nanoparticle films and so allow us to directly look at the interparticle structure itself. Specifically, we studied properties such as interparticle spacing and domain size as a function of varying the same parameters as the mechanical properties studies. This had the end goal of using the microscopic properties of the film to better understand and explain the larger-scale properties we first studied.
During my 3rd year, I was given my first opportunity to work at the Advanced Photon Source at Argonne National Laboratory. The APS is the 1104-meter- circumference particle accelerator and storage ring that produces and stores high-energy x-ray beams, which are then used for a multitude of measuring techniques in an even larger multitude of scientific fields. Our PI Dr. Binhua Lin is the Deputy Director and Project manager of ChemMatCARS, one of UChicago’s 3 sectors at APS. At ChemMatCARS, we use the x-ray source to perform liquid-surface x-ray scattering on our nanoparticle films. We spread a film of our nanoparticles on the water surface, and can then perform x-ray diffraction experiments on the film to study the same structural properties, such as inter-particle lattice spacing and domain correlation length, that we did with electron microscopy, but with a 1000x larger sample size than what we get with microscopy. Thus x-ray diffraction is a much more accurate representation of the film’s structural properties. Throughout the summer after my 3rd year I continued to work at APS performing structural studies and data analyses on gold nanoparticle films with various ligand molecule lengths and concentrations.
Currently, I am working on my thesis, which will involve a study to determine the actual surface coverage of the thiol ligands on our gold nanoparticles as a function of the total thiol concentration in the overall nanoparticle solution. This will allow me to tie together the majority of the projects that I have been working on during my time in this lab, which I am very excited about. I’m very grateful to my research advisors, and UChicago, for giving me the opportunity to have had such a fulfilling and long-term research experience.
Undergraduate Student: Class of 2017
Majors: Physics and Mathematics
Hometown: Schaefferstown, PA
Awards: Barry M. Goldwater Scholarship, Phi Beta Kappa, Walter and Fay Selove Prize for Senior Research, Dean's List
Research: Fluids, Condensed Matter
Research Advisors: Wiliam Irvine, Norman Lebovitz
During my time as an undergraduate, I have had the opportunity to be involved in a number of research projects within fluid dynamics and condensed matter physics. My first research position started with Professor Lebovitz in my second year. Throughout the winter and spring quarters of my second year we worked through seminal papers in fluid dynamics so I could obtain a background in the theory. Later in spring quarter we began working to study the stability of Riemannian ellipsoids, namely the stability of self-gravitating fluids with linear velocity profile confined to an ellipsoidal shape. Professor Lebovitz wanted to restrict the Poisson bracket formulation for inviscid fluid mechanics to Riemann ellipsoids so as to probe their stability. In order to investigate the theory behind this restriction I participated in the NSF REU in mathematics at UChicago and wrote a paper on Poisson geometry. Writing it revealed to me that using the Poisson bracket made obscure conserved quantities into obvious consequences of geometry. This motivated the decision to pass from the system of 18 ODEs describing the Riemann ellipsoids to the Poisson bracket for the ellipsoids. Simultaneously I did original work to numerically analyze whether the Poisson bracket formulation could be used to find Energy-Casimir functions for evaluating stability. It is for this work that I received the Goldwater scholarship. In the winter of my junior year my work revealed that the proposed Energy-Casimir functions were not useful for stability analysis, at which point Professor Lebovitz suggested finishing the project.
I resolved to continue studying fluids due to my interest in the subject. When I heard in the early spring that Professor Irvine of the James Franck Institute was investigating the similarities between vortex knot dynamics in inviscid fluids and superfluids, I saw a potential to use the intuition I had gained while working with Professor Lebovitz. Thus in the spring of my junior year and in the past summer, I worked with Professor Irvine building a simulation of an airfoil moving in a superfluid. I have also been building analytical tools that will help to reveal how similar the superfluid flow around the airfoil is to the well-known ideal fluid flow around the airfoil. Preliminary analysis suggests that the flows appear to be quite similar, potentially allowing for a major simplification in describing superfluid flow. Additionally, I am studying vortex nucleation from the airfoil in an attempt to gain some insight into this not well understood phenomenon. I plan to continue working with Professor Irvine throughout the rest of this year to continue this research.