UC Davis

Instrumentation is the bedrock of spectroscopic investigation regardless of the location on the electromagnetic spectrum being studied. Although X-ray spectroscopy and Nuclear Magnetic Resonance (NMR) spectroscopy rely on different energies of electromagnetic waves, the goal of both types of spectroscopies is to use electromagnetic waves to excite an atom and to measure the resulting perturbation. X-ray nanochemistry follows the physical and chemical interactions between high energy photons used to excite electrons and the resulting chemical reactions from the electron depositing energy into the surrounding medium. These interactions are measured using chemical dosimeters, but can also be studied through calculations based on physical interactions. To improve the effectiveness of these studies, new instrumentation has been developed to control the location of X-rays to increase the dose enhancement at a specific location. This instrument can also be improved by using X-ray calculations that model sample dosimetry produced by an algorithm giving more accurate results. In Chapter 2, the development and implementation of an improved scanning focusing X-ray source with a variable focal length for extremely high dose enhancement of a sample containing AuNPs is discussed. In Chapter 3, calculations to simulate the scanning focusing instrument from Chapter 2 are demonstrated to accurately simulate the beam intensity, shape, and dose profile measured by the instrument.Solid state NMR uses the rapid spinning of a solid sample at 54.74° in order to acquire spectra that would otherwise not be measurable in a static state using a process called magic angle spinning (MAS) [1,2]. This spinning uses specialized and expensive equipment. To improve the sampling signal for a low cost, widely available instrument, a 3D printed MAS rotor was developed. This device improves the signal from solid KBr and NaBr to produce narrow linewidths that improve sampling signal. To further improve upon the existing spectroscopic method, the device was modified to allow for up to 8 samples to be measured simultaneously. This gives the instrument the ability to measure samples that it was otherwise unable to analyze for a few dollars per unit. In Chapter 4, the development of a 3D printed MAS probe for a low field NMR instrument is shown and the 3D printing techniques used to improve signal acquisition through a multiple stator design are demonstrated.