d.w.rowlands [at] gmail.com
Graduate Research at MIT
My graduate research at MIT was conducted with Professor Sylvia Ceyer, studying silicon surface chemistry and the reaction of Si(100) crystals with gas-phase reagents, particularly F2 and XeF2. This work was conducted under ultra-high vacuum using supersonic molecular beams as gas sources and Auger, thermal desorption, and time-of-flight-sensitive mass spectrometry to observe the crystal surface and reaction products. I also wrote a classical molecular dynamics simulation in Python to model the gas-surface interactions.
In the process of carrying out this research, I repaired and used an ultra-high vacuum molecular beam scattering apparatus with a differentially pumped rotatable, time-of-flight sensitive quadrupole mass spectrometer. I rebuilt mechanical and ionization vacuum pumps and repaired turbomolecular vacuum pumps, repaired power and sensor electronics, rebuilt and repaired a mass spectrometer, and performed helium leak checking. I also served as my lab's environmental health and safety officer during this time, making sure that the lab followed safety and hazardous materials policies and liaising with the MIT Environmental Health and Safety Office.
I presented posters on this work at the 2011 and 2013 Gordon Research Conferences on Dynamics at Surfaces in Newport, RI. I also presented a talk on it, and on potential future work studying the mechanism by which triplet oxygen molecules can react with singlet silicon-silicon bonds to produce singlet products, as part of the MIT Chemistry Student Seminar series. A full write-up of my graduate research can be found in my Master's thesis.
Undergraduate Research at Caltech
In the Barton Group, I worked with a grad student, Fangwei Shao, on developing and testing cyclometalated iridium(III) complexes as photoactivated redox reagents that could be intercalated into DNA as probes of DNA charge transport. We hoped to develop complexes capable of reducing N4-cyclopropylcytosine and oxidizing N2-cyclopropylguanine, modified nitrogenous bases that can be introduced into DNA. The distance dependence of electron and hole transport through the DNA strand could then be studied by tethering the complexes a known distance from the modified bases.
In the Weitekamp group, I worked on the development of new methods to induce magnetic spin hyperpolarization in 13C atoms in small biomolecules for use as safe MRI tracers in human and animal subjects. Hyperpolarization of 13C spins allows NMR spectra and MRI images to be collected much more rapidly, making it possible to produce real-time "movies" of the movement of metabolites in the living organisms. However, the main methods for producing hyperpolarized 13C nuclei, Dynamic Nuclear Polarization and PASADENA, require the introduction of toxic compounds and are not suitable for use with humans or non-sacrificial research animals. My project was to develop an apparatus capable of transferring nuclear polarization from 129Xe nuclei to the 13C nuclei in pyruvate molecules and deliver the pyruvate as a biologically-safe solution for injection before the hyperpolarization dissipated. I wrote up the results of this work as a chemistry senior thesis.
High School Research at NASA-Goddard Space Flight Center
While in high school, I did an internship studying the contribution of light pollution to the spectrum of the skyglow with Dr. Ronald Oliversen at NASA's Goddard Space Flight Center during the 2004-2005 school year. I collected spectra of various light sources that are common sources of light pollution and used a 36" Cassifrain reflector telescope at the Goddard Geophysical and Astronomical Observatory in Beltsville, Maryland to collect spectra of the sky glow in the directions of the District of Columbia, Baltimore, Maryland, and Annapolis, Maryland. I then developed a set of scripts in IDL (Interactive Data Language) to analyze these spectra and determine the relative contributions of different light sources to the sky glow over each city.
I wrote up the results of this research as a senior thesis for the Research Practicum requirement of the Science and Technology program at Eleanor Roosevelt High School in Greenbelt, Maryland.