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Detection Of Nitrogen Dioxide Via Graphene-Enhanced Raman Scattering, Spencer Hazeslip
Detection Of Nitrogen Dioxide Via Graphene-Enhanced Raman Scattering, Spencer Hazeslip
Chemistry & Biochemistry Undergraduate Honors Theses
This paper presents the development of a nitrogen dioxide (NO2) sensor that utilizes the phenomenon of graphene-enhanced Raman scattering (GERS). The sensor consists of monolayer graphene on a silicon wafer, functionalized noncovalently with Copper(II) 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine (CuTTPc) via the solution soaking method. A custom sensing chamber was constructed to enable Raman spectra to be collected during NO2 exposure. The response of the sensor was found to be linear between 10 and 100 ppm NO2, indicating that it could be used for both detection and quantification. Furthermore, the sensor was shown to be reusable after …
A Geochemical And Mineralogical Evaluation Of The Mona Lisa Turquoise Mine, Polk County, Arkansas, Alexander Arai Goodsuhm
A Geochemical And Mineralogical Evaluation Of The Mona Lisa Turquoise Mine, Polk County, Arkansas, Alexander Arai Goodsuhm
Graduate Theses and Dissertations
The presence of turquoise in Arkansas has long been disputed by geologists and gem collectors. Despite the prevalence of other phosphate minerals in Arkansas, such as planerite, wavellite, and variscite, the absence of an obvious copper (Cu) source required for turquoise formation was considered too great of an obstacle for turquoise mineralization. In this study, geologic, mineralogical, and geochemical techniques provide overwhelming evidence that the novaculite-hosted Mona Lisa Mine in Arkansas does produce turquoise. X-ray diffraction and Raman spectroscopy have confirmed the structural nature of the material and identified other phosphate minerals, such as crandallite, often found in assemblage with …