Quantitative Structure-Activity Relationships Study on the Rate Constants of Polychlorinated Dibenzo-p-Dioxins with OH Radical.

The OH-initiated reaction rate constants (kOH) are of great importance to measure atmospheric behaviors of polychlorinated dibenzo-p-dioxins (PCDDs) in the environment. The rate constants of 75 PCDDs with the OH radical at 298.15 K have been calculated using high level molecular orbital theory, and the rate constants (kα, kβ, kγ and kOH) were further analyzed by the quantitative structure-activity relationships (QSAR) study.

Theoretical study on the degradation reaction of octachlorinated dibenzo-p-dioxin with atomic oxygen O((3)P) in dielectric barrier discharge reactor.

Dielectric barrier discharges (DBD) have been used in the degradation of dioxins due to the large number of excimers and free radicals produced in discharge process. In this article, the density functional theory (DFT) is used to study the degradation mechanism of octachlorinated dibenzo-p-dioxin (OCDD) with the atomic oxygen O((3)P) in DBD reactor. The reactants, intermediates, transition states and products are optimized at the MPWB1K/6-31+G(d,p) level.

The OH-initiated atmospheric reaction mechanism and kinetics for levoglucosan emitted in biomass burning.

Levoglucosan is a typical molecular tracer of biomass-burning aerosols in the atmosphere. The mechanism for OH-initiated reaction with levoglucosan is studied at the level of MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p). The possible subsequent reactions in the presence of O2, NO and H2O are also taken into consideration.

The degradation of 1,2,4-trichlorobenzene using synthesized Co3O4 and the hypothesized mechanism.

Co(3)O(4) was synthesized with cabbage-like, plate-like and sphere-like morphologies. The effect of different morphologies on the degradation of 1,2,4-trichlorobenzene (1,2,4-TrCB) was evaluated, and the cabbage-like Co(3)O(4) exhibited the highest reactivity. The degradation of 1,2,4-TrCB on the cabbage-like Co(3)O(4) is hypothesized to act competitively via hydrodechlorination and oxygen-attacking pathways.

Density functional study of structures and electron affinities of BrO₄F/BrO₄F-.

The structures, electron affinities and bond dissociation energies of BrO(4)F/BrO(4)F(-) species have been investigated with five density functional theory (DFT) methods with DZP++ basis sets. The planar F-Br..