The Development of Photonic Crystal Optics and Wide-field Raman Imaging Spectrometers for Trace Explosive Detection

There is currently an urgent, unmet need for sensitive and specific instruments that can detect trace explosive residues from a distance, allowing suspicious objects to be remotely screened for the presence of explosives before the approach of law enforcement or military personnel. UV resonance Raman spectroscopy is a powerful technique that enables precise determination of the chemical identity of samples excited by monochromatic light. Furthermore, Raman spectroscopy is well suited for standoff detection, which makes this technique ideal as a method to screen for trace quantities of explosives from a distance. However, UV spectroscopies are hampered by the lack of commercially available optical devices that function in the deep UV spectral region from 200-300 nm due to the fact that many materials absorb light strongly at these wavelengths. Building deep UV spectroscopic instrumentation capable of standoff trace explosive detection therefore requires the development of optics that function in this spectral region. In this work, we developed deep UV photonic crystal optical devices and deep UV resonance Raman imaging spectrometers based on those devices for standoff trace explosive detection purposes. We first developed a novel, proof of concept wide-field Raman imaging spectrometer in the visible spectral region to demonstrate the utility of photonic crystals as wide-field Raman imaging optics. Using knowledge gained during those studies, we then developed a deep UV wide-field Raman imaging spectrometer that utilized 229 nm excitation and a deep UV diffracting photonic crystal to image, detect, and chemically differentiate 10 μg/cm2 quantities of solid explosive at 2.3 m standoff. These studies demonstrated the feasibility and promise of deep UV wide-field imaging and deep UV diffracting photonic crystal optics. Finally, we developed the first deep UV diffracting inverse opal photonic crystal to increase the mechanical durability and shelf life of photonic crystal optical devices, opening the door for the development of field usable deep UV wide-field imaging instrumentation for standoff trace explosive detection

Antimicrobial Fe 2 O 3 -CuO-P 2 O 5 glasses

Glasses with high antimicrobial efficacy were developed in the Fe2O3-CuO-P2O5 ternary system to mitigate fomite-mediated transmission of infectious diseases in high-risk settings such as hospitals, daycares, and nursing homes. Binary CuO-P2O5 glasses were not durable enough for use as high touch point articles, so Fe2O3 was added to the compositions to increase the chemical durability. The amount of Cu leachate decreased by at least 3 orders of magnitude when Fe2O3 was increased from 0 to 13.1 mol%. At the highest Fe2O3 contents and corresponding highest durability, the glass was no longer able to pass a test of antimicrobial efficacy with 5 log kill for all other compositions. Ab-initio molecular dynamics simulations showed increasing bridging oxygen species at the expense of non-bridging oxygen species with the increase in Fe2O3 content, showing that the glasses exhibited increased chemical durability because they were more interconnected and structurally bound. Experimental results with glasses at fixed CuO and decreasing Fe2O3 confirmed that Fe2O3 content (not CuO) controlled the Cu release rate and, thus, the antimicrobial efficacy of the glasses. The significance of the oxidation state of the leached Cu was overwhelmed by the importance of the amount of Cu leachate

The Approach to Clinical Xenotransplantation

(Statement of Responsibility) by Joshua H. Hufziger(Thesis) Thesis (B.A.) -- New College of Florida, 1999(Electronic Access) RESTRICTED TO NCF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE(Bibliography) Includes bibliographical references.(Source of Description) This bibliographic record is available under the Creative Commons CC0 public domain dedication. The New College of Florida, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.(Local) Faculty Sponsor: Beulig, Alfre