On the basis of a mechanistic model, the overall and liquid mass transfer coefficients of aroma compounds were estimated during aroma release when an inert gas diluted the static headspace over simple ethanol/water solutions (ethanol concentration = 120 mL x L(-1)). Studied for a range of 17 compounds, they were both increased in the ethanol/water solution compared to the water solution, showing a better mass transfer due to the presence of ethanol, additively to partition coefficient variation. Thermal imaging results showed differences in convection of the two systems (water and ethanol/water) arguing for ethanol convection enhancement inside the liquid. The effect of ethanol in the solution on mass transfer coefficients at different temperatures was minor. On the contrary, at different headspace dilution rates, the effect of ethanol in the solution helped to maintain the volatile headspace concentration close to equilibrium concentration, when the headspace was replenished 1-3 times per minute.
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http://dx.doi.org/10.1021/jf800225y | DOI Listing |
ACS EST Air
January 2025
Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Wildfires at the wildland-urban interface (WUI) have been increasing in frequency over recent decades due to increased human development and shifting climatic patterns. The work presented here focuses on the impacts of a WUI fire on indoor air using field measurements of volatile organic compounds (VOCs) by Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-TOF-MS). We found a slow decrease in VOC mixing ratios over the course of roughly 5 weeks starting 10 days after the fire, and those levels decreased to ∼20% of the initial indoor value on average.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Mechanical Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
Background: The development of heat transfer devices used for heat conversion and recovery in several industrial and residential applications has long focused on improving heat transfer between two parallel plates. Numerous articles have examined the relevance of enhancing thermal performance for the system's performance and economics. Heat transport is improved by increasing the Reynolds number as the turbulent effects grow.
View Article and Find Full Text PDFLoading with non-metal cocatalysts to regulate interfacial charge transfer and separation has become a prominent focus in current research. In this study, g-CN/CNT composites loaded with non-metallic cocatalysts were prepared through pyrolysis using urea and CNTs. Various characterization techniques, including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), photoelectrochemical (PEC) analysis, fluorescence lifetime spectroscopy (TRPL), electron paramagnetic resonance spectroscopy (ESR), and photoluminescence (PL) spectroscopy, were employed to analyze the sample's microstructure, phase composition, elemental chemical states, and photoelectronic properties.
View Article and Find Full Text PDFMicrob Biotechnol
January 2025
Izmir Biomedicine and Genome Center, Izmir, Turkey.
Low-cost and safe vaccines are needed to fill the vaccine inequity gap for future pandemics. Pichia pastoris is an ideal expression system for recombinant protein production due to its cost-effective and easy-to-scale-up process. Here, we developed a next-generation SARS-CoV2 Omicron BA.
View Article and Find Full Text PDFAnal Chem
January 2025
Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
Lipid A, a well-known saccharolipid, acts as the inner lipid-glycan anchor of lipopolysaccharides in Gram-negative bacterial cell membranes and functions as an endotoxin. Its structure is composed of two glucosamines with β(1 → 6) linkages and various fatty acyl and phosphate groups. The lipid A structure can be used for the identification of bacterial species, but its complexity poses significant structural characterization challenges.
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