A solution of atrazine in a TiO 2 suspension, an endocrine disruptor in natural water, was tentatively treated by microwave-assisted photocatalytic technique. The effects of mannitol, oxygen, humic acid, and hydrogen dioxide on the photodegradation rate were explored. The results could be deduced as follows: the photocatalytic degradation of atrazine fits the pseudo-first-order kinetic well with k = 0.0328 s -1 , and $OH was identified as the dominant reactant. Photodegradation of atrazine was hindered in the presence of humic acid, and the retardation effect increased as the concentration of humic acid increased. H 2 O 2 displayed a significant negative influence on atrazine photocatalysis efficiency. Based on intermediates identified with gas chromatography-mass spectrometry (GC-MS) and Liquid chromatography-mass spectrometry (LC-MS/MS) techniques, the main degradation routes of atrazine are proposed.

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The paper presents a sufficient condition ensuring global exponential stability for high-order neural networks with time-varying coefficients and delays. The result allows for the consideration of all unbounded neuron activation functions, while the previous results allowed for the consideration of bounded activation functions (|gi(x)| < 1, |gi(x)| < μi|x|). The method is based on basic analytical techniques and differential inequality techniques. The result of this paper is new and it complements previously known results. Several remarks are worked out to demonstrate the advantage of our result.