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Previous studies have suggested that the photochemistry of nitroaromatics in organic solvents can vary significantly from the photochemistry in aqueous solutions. This work compares the photodegradation of 2-nitrophenol (2NP), 4-nitrophenol (4NP), 2,4-dinitrophenol (24DNP), and 2,4,6-trinitrophenol (246TNP) in 2-propanol and water to better understand the photochemical loss of nitrophenols in atmospheric organic particles and aqueous droplets. Polychromatic quantum yields were determined by monitoring the loss of absorbance of each nitrophenol with UV/vis spectroscopy in the presence of an acid (undissociated nitrophenol) or base (nitrophenolate). There was no orderly variation between loss rates in the organic and aqueous phases: 2NP and 4NP had similar yields in the two solvents. 246TNP was an outlier in these results as it dissociated in both acidified 2-propanol and water due to its exceptionally strong acidity. A notable result is that only for 24DNP was a dramatically increased reactivity found in 2-propanol compared to that in water. Time-dependent density functional theory calculations were carried out to characterize the excited state energies and absorption spectra with a conductor-like polarizable continuum model or explicit solvation by a few solvent molecules. Explicit solvent calculations suggest the enhanced reactivity of 24DNP in 2-propanol is due to the strong interaction between a 2-propanol molecule and an –NO 2 group in the excited state. For the other nitrophenols, the solvent effects on electronic structure were minimal. Overall, the observations in this work suggest that solvent effects on the electronic structure and condensed-phase photochemistry of nitrophenols are minimal, with the exception of 24DNP. 

Background: Fluid intelligence (FI) involves abstract problem-solving without prior knowledge. Greater age-related FI decline increases Alzheimer’s disease (AD) risk, and recent studies suggest that certain dietary regimens may influence rates of decline. However, it is uncertain how long-term food consumption affects FI among adults with or without familial history of AD (FH) or APOE4 (ɛ4). Objective: Observe how the total diet is associated with long-term cognition among mid- to late-life populations at-risk and not-at-risk for AD. Methods: Among 1,787 mid-to-late-aged adult UK Biobank participants, 10-year FI trajectories were modeled and regressed onto the total diet based on self-reported intake of 49 whole foods from a Food Frequency Questionnaire (FFQ). Results: Daily cheese intake strongly predicted better FIT scores over time (FH-: β= 0.207, p < 0.001; ɛ4–: β= 0.073, p = 0.008; ɛ4+: β= 0.162, p = 0.001). Alcohol of any type daily also appeared beneficial (ɛ4+: β= 0.101, p = 0.022) and red wine was sometimes additionally protective (FH+: β= 0.100, p = 0.014; ɛ4–: β= 0.59, p = 0.039). Consuming lamb weekly was associated with improved outcomes (FH-: β= 0.066, p = 0.008; ɛ4+: β= 0.097, p = 0.044). Among at risk groups, added salt correlated with decreased performance (FH+: β= –0.114, p = 0.004; ɛ4+: β= –0.121, p = 0.009). Conclusion: Modifying meal plans may help minimize cognitive decline. We observed that added salt may put at-risk individuals at greater risk, but did not observe similar interactions among FH- and AD- individuals. Observations further suggest in risk status-dependent manners that adding cheese and red wine to the diet daily, and lamb on a weekly basis, may also improve long-term cognitive outcomes.