Publications by authors named "Robert H Magnuson"

Despite the same basic ingredients used in brewing, there is a significant variation in beer styles. With the rapid increase in craft brewing, beer styles have become even more numerous and complex in the recent past. A GC-MS/VUV (post-column split for dual detection) instrument with headspace high capacity SPME was used to investigate 21 different beers which represent three beer styles - India pale ales, blondes, and hefeweizens.

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Hen egg yolk from chicken eggs were examined for their mycotoxin, hormone, and fat-soluble vitamin content. A method was developed for multi-class analysis of egg yolk using a dilute/precipitate, centrifuge, and shoot process coupled with on-line sample clean-up using restricted access media with LC-MS/MS. Matrix effects were evaluated and a standard addition protocol with internal standards was chosen for analyte quantitation.

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Rationale: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) provides detailed information for the analysis of ethoxylated alcohols and polymers. In this study, five friction reducers used in commercial hydraulic fracturing processes were analyzed in their as-received form to identify their ethoxylated alcohol content. The friction reducers were then subjected to lab-simulated downhole conditions.

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