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The selective activation of renewable carboxylic acids could enable the formation of a variety of highly valuable renewable products, including surfactants, valuable dienes, and renewable hydrogen carriers. A kinetic study is performed to enhance understanding of the selective deoxygenation of carboxylic acid on promoted MoO3 at mild temperatures. Although several studies indicate that deoxygenation of oxygenated biomass-derived compounds on MoO3 occurs via a reverse Mars−van Krevelen mechanism, this study suggests that the deoxygenation of pentanoic acid (PA) on an oxygen vacancy can also be explained by a Langmuir−Hinshelwood mechanism. A detailed analysis of the experimental data indicates that the incorporation of Pt on MoO3 shifts the reaction order with respect to hydrogen from 1 to 0.5 at a low partial pressure of PA. We reveal that the rate-determining step (RDS) shifts upon the incorporation of Pt from H2 dissociation to H addition to adsorbed acid molecules. We further illustrate how the RDS can shift as a function of PA coverage. The inhibition effect of PA and its possible causes are discussed for both MoO3 and 0.05 wt % Pt/MoO3 catalysts. Here, we decouple promoter effects from the creation of highly active sites located at the Pt/MoO3 interface. The nature of the active site involved upon Pt incorporation is also studied by separating Pt from MoO3 at a controlled distance using carbon nanotubes as hydrogen bridges, confirming that the kinetically relevant role of Pt is to serve as a promoter of the MoO3. 

Abstract Satellite‐based post‐tornado assessments have been widely used for the detection of tornado tracks, which heavily relies on the identification of vegetation changes through observations at visible and near‐infrared channels. During the deadly 10–11 December 2021 tornado outbreak, a series of violent tornadoes first touched down over northeastern Arkansas, an area dominated by cropland with rare vegetation coverage in winter. Through the examination of Moderate Resolution Imaging Spectroradiometer multi‐spectral observations, this study reveals significant scars on shortwave infrared channels over this region, but none are captured by visible and near‐infrared channels. The dominant soil type is aquert (one of vertisols), whose high clay content well preserves the severe changes in soil structure during the tornado passage, when the topmost soil layer was removed and underlying soil with higher moisture content was exposed to the air. This study suggests a quick post‐tornado assessment method over less vegetated area by using shortwave infrared channels.