Publications by authors named "Arman Peyravi"

Non-medical masks such as disposable non-medical, commercially produced cloth, and homemade masks are not regulated like surgical masks. Their performance, in terms of filtration efficiency and breathability, is variable and unreliable. This research provides a quantitative evaluation of various non-medical masks, assesses their fabrics' potential for the reduction of transmission of bioaerosols such as the SARS-CoV-2 virus, and compares them to surgical masks and N95 filtering facepiece respirators.

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Irreversible adsorption, or heel buildup, negatively impacts activated carbon performance and shortens its lifetime. This study elucidates the interconnections between flow rate and the oxygen impurity of desorption purge gas with heel buildup on beaded activated carbon (BAC). Nine thermal desorption scenarios were explored, varying nitrogen purge gas oxygen impurity levels (<5 ppmv, 10,000 ppmv, 210,000 ppm (21 %)) and flow rates (0.

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This study evaluated the adsorption of five volatile organic compounds (VOCs) on Opoka, precipitated silica, and palygorskite, to elucidate the effect of their pore size on VOCs adsorption. The adsorption capacity of these adsorbents is not only highly correlated with their surface area and pore volume, but also notably improved by the presence of micropores. The variation in adsorption capacity for different VOCs was primarily influenced by their boiling point and polarity.

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Microwave regeneration of adsorbents offers several advantages over conventional regeneration methods; however, its application for microwave transparent adsorbents such as polymers is challenging. In this study, hypercrosslinked polymer/graphene oxide (GO) nanocomposites with large surface area and enhanced microwave absorption ability were synthesized. Polymers of 4, 4´-bis ((chloromethyl)-1, 1´-biphenyl- benzyl chloride) were hypercrosslinked through the Friedel-Crafts reactions.

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Adsorbents with high surface area, thermal stability and microwave absorption ability are highly desired for cyclic adsorption and microwave regeneration processes. However, most polymeric adsorbents are transparent to microwaves. Herein, porous hyper-crosslinked polymers (HCP) of (4,4'-bis((chloromethyl)-1,1'-biphenyl-benzyl chloride)) with different carbon black (CB) contents were synthesized via the Friedel-Crafts reaction.

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Mesoporous silica MCM-41 was synthesized by a facile hydrothermal treatment using sodium silicate extracted from natural Opoka as the Si source. The dynamic adsorption and desorption of organic vapors mixture on the MCM-41 were investigated. Characterization of the textural properties of the samples showed that the sample synthesized with a molar ratio of CTAB/Si = 0.

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