Publications by authors named "Denise Dorhout"

We have compared and assessed the suitability of several chromatographic methods for the analysis of long chain alkenones and long chain diols and the associated paleotemperature proxies (U and LDI). We evaluated the traditional methods for the analysis of the U and the LDI, gas chromatography (GC) - flame ionization detection (FID) and GC mass spectrometry (MS) using selected ion monitoring (SIM), respectively, and developed a new method using GC-MS/MS in multiple reaction monitoring mode (MRM) for the analysis of long chain diols as well as a method for automatic silylation of diols using a robot autosampler. Finally, we evaluated liquid chromatography (LC) methods to simultaneously measure the U and the LDI, using ultra high performance LC (UHPLC) with low (nominal mass) resolution MS in SIM mode, and UHPLC with high resolution MS (HRMS).

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Suspended particulate matter (SPM) was collected along the Amazon River in the central Amazon basin and in three tributaries during the rising water (RW), high water (HW), falling water (FW) and low water (LW) season. Changes in the concentration and the distribution of branched glycerol dialkyl glycerol tetraethers (brGDGTs), i.e.

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