Effect of humus on photodegradation of quinclorac under different fertilization modes.

Humus is a specific kind of organic matter widely distributed in soils. The characteristics of humus have significant impacts on the fate of pollutants in the environment. In this study, we examined the effects of fertilization modes from rice rotation systems on the contents, spectral properties, photochemical activity, and photosensitization of quinclorac (QNC) of humic (HA) and fulvic acids (FA).

[Degradation of Triclosan by Heat Activated Persulfate Oxidation].

Sulfate radical (SO)-based advanced oxidation technologies (SR-AOPs) are widely used for remediation of contaminated groundwater and soils. This study investigated the reaction kinetics, products, and transformation pathways of triclosan, a widely used antimicrobial agent, during its degradation by heat activated persulfate oxidation. Experimental results revealed that increasing temperature or initial persulfate concentration significantly enhanced the degradation of triclosan.

[Formation of Halogenated By-products in Co²⁺ Activated Peroxymonosulfate Oxidation Process].

Sulfate radicals (SO₄·⁻) generated by Co²⁺ catalyzed activation of peroxymonosulfate (PMS) are highly oxidative and can be applied to degrade various organic pollutants. It was revealed in this research that bromide could be transformed in this process to reactive bromine species which reacted with phenol subsequently, leading to the formation of bromophenols and brominated by-products such as bromoform and dibromoacetic acid. The formation of the brominated by-products first increased and then decreased.

[Photodegradation of atenolol in aqueous nitrate solution].

The aqueous photolysis of beta-blocker atenolol (ATL) using Xe lamp as simulated solar irradiation source was investigated in the presence of nitrate ions. The effects of nitrate ion concentration, solution pH value, and concentration of bicarbonate and humic substance on the photodegradation of ATL were studied. The results showed that photodegradation of ATL in nitrate solution followed pseudo-first-order kinetics.

[Photodegradation of UV filter PABA in nitrate solution].

The aqueous photolysis of a UV filter p-aminobenzoic acid (PABA) using Xe lamp as simulated solar irradiation source was investigated in the presence of nitrate ions. The effects of pH, concentration of nitrate ions and concentration of humic substance in natural water on the photodegradation of PABA were studied. The results showed that photodegradation of PABA in nitrate solution followed the first order kinetics.