David Grass

Preprint · March 13, 2024 Carbon-based black pigments, a widely used class of pigments, are difficult to differentiate with the noninvasive techniques currently used in cultural heritage science. We utilize pump-probe microscopy to distinguish four common carbon-based black pigment ... Link to item Cite

Non-destructive Three-dimensional Imaging of Artificially Degraded CdS Paints by Pump-probe Microscopy

Preprint · October 20, 2023 Cadmium sulfide (CdS) pigments have degraded in several well-known paintings, but the mechanisms of degradation have yet to be fully understood. Traditional non-destructive analysis techniques primarily focus on macroscopic degradation, whereas microscopic ... Link to item Cite

Contrast mechanisms in pump-probe microscopy of melanin

Preprint · July 1, 2022 Pump-probe microscopy of melanin in tumors has been proposed to improve diagnosis of malignant melanoma, based on the hypothesis that aggressive cancers disaggregate melanin structure. However, measured signals of melanin are complex superpositions of mult ... Link to item Cite

Low-cost measurement of facemask efficacy for filtering expelled droplets during speech

Preprint · June 22, 2020 AbstractMandates for mask use in public during the recent COVID-19 pandemic, worsened by global shortage of commercial supplies, have led to widespread use of homemade masks and mask alternatives. It is ass ... Full text Cite