Publications by authors named "R Maggie Connatser"

Lignocellulosic biomass offers a renewable carbon source which can be anaerobically digested to produce short-chain carboxylic acids. Here, we assess fuel properties of oxygenates accessible from catalytic upgrading of these acids a priori for their potential to serve as diesel bioblendstocks. Ethers derived from C and C carboxylic acids are identified as advantaged fuel candidates with significantly improved ignition quality (>56% cetane number increase) and reduced sooting (>86% yield sooting index reduction) when compared to commercial petrodiesel.

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Exposure to light or heat, or simply a dearth of fingerprint material, renders some latent fingerprints undetectable using conventional methods. We begin to address such elusive fingerprints using detection targeting photo- and thermally stable fingerprint constituents: surface-enhanced Raman spectroscopy (SERS). SERS can give descriptive vibrational spectra of amino acids, among other robust fingerprint constituents, and good sensitivity can be attained by improving metal-dielectric nanoparticle substrates.

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Photo- and thermal-degradation studies on eccrine fingerprint components are presented herein. Dilute distinct solutions of urea, lactic acid, and seven amino acids were deposited on steel coupons and Teflon disks, exposed to artificial sunlight or heat, extracted, and analyzed. This aim of this study was to determine whether the investigated eccrine components, previously determined to be Raman active for a parallel study, experienced photo- or thermally induced degradation, and if so, to determine the rate and identify any detectable products.

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Teratogenic, carcinogenic, and pervasive endocrine disrupting compounds (EDCs) in suspect water systems present an immediate threat to both the environment and potable water supplies. The US Environmental Protection Agency mandated research regarding suspect EDCs, personal care products, and pesticide pollution requires the use of suitable methods of analysis that can perform extraordinarily well in the field and show low "cost to benefit" ratios. Such methods must increasingly address the need for enhanced sensitivity and selectivity in interrogating complex mixtures.

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Adding vibrational spectroscopies to the arsenal of detection modes for microfluidics (mufluidics) offers benefits afforded by structurally descriptive identification of separated electrophoretic bands. We have previously applied surface-enhanced Raman spectroscopy (SERS) detection with nanocomposite metal-elastomer substrates as a detection mode in mufluidic channels. To create these mufluidic-SERS devices, silver-PDMS substrate regions are integrated into the architecture of a separation chip fabricated from PDMS or glass.

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