BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4//
BEGIN:VEVENT
UID:20250828T103732EDT-9926E8r7Gr@132.216.98.100
DTSTAMP:20250828T143732Z
DESCRIPTION:Gaseous Mercury Uptake on Fly Ash and Iron Oxide Particles: Rol
 e of Oxygen\, Humidity and Radiation\n\nDespite the proposed importance in
  Hg cycling\, little is known about heterogeneous Hg chemistry\, specifica
 lly on ubiquitous particle surfaces in the environment. To address this ga
 p in knowledge\, we performed systematic physical and chemical characteriz
 ation of three types of coal combustion fly ash and naturally ubiquitous γ
 -Fe2O3\, α-FeOOH and Fe3O4  nano and microparticles\, employed as proxies 
 for dust aerosols\, using SMPS\, OPS\, NTA\, GC-MS\, TEM and BET analysis.
  Size distributions of fly-ash was measured in the 10-2 – 101 µm size rang
 e\, while individual iron oxides particles were found to be < 50 nm. We st
 udied kinetics of Hg0(g) uptake on these particles at ambient pressure (76
 0 +/- 5 Torr) and temperatures (295 +/- 2  K) in air and N2 diluents\, wit
 h 0 % ≤ RH ≤ 100 % and UV-visible irradiation (290 nm ≤ λ ≤ 700 nm). The a
 pparent pseudo first order rate constant of Hg0 uptake increased rapidly f
 rom (9.5 ± 0.7) × 10-4 min-1 for dark reactions to (7.5 ± 2.5) × 10-2 min-
 1 for irradiated experiments on γ-Fe2O3\, and from (3.0 ± 0.4) × 10-4  min
 -1 to (9.6 ± 2.1) × 10-2 min-1 on α-FeOOH. The apparent rate constants for
  Hg0 uptake on Cumberland\, Nanticoke and Shawnee fly-ash samples are foun
 d to be (1.2 ± 0.2) ×10-3 min- 1\, (0.4 ± 0.04) ×10-3 min-1 and (4.4 ± 0.9
 ) × 10-2 min-1 respectively\, under our experimental conditions. We observ
 ed that humidity and O2 promoted Hg0 capture on fly-ash increasing reactio
 n kinetics by c.a. 1.5 - 8 fold\n
DTSTART:20160413T183000Z
DTEND:20160413T190000Z
LOCATION:Room 934\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue 
 Sherbrooke Ouest
SUMMARY:Student Seminar: Uday Kurien
URL:/meteo/channels/event/student-seminar-uday-kurien-
 255088
END:VEVENT
END:VCALENDAR