This study comparatively investigated atrazine (ATZ) degradation by irradiation at the wavelength of 254 nm in the presence of peroxides including hydrogen peroxide (H2O2), peroxymonosulfate (HSO5(-)), and persulfate (S2O8(2-)) at various initial ATZ concentrations and oxidant dosages. The effects of water matrix, such as carbonate/bicarbonate (HCO3(-)/CO3(2-)), chloride ions (Cl(-)), and natural organic matter (NOM), were evaluated on these three advanced oxidation processes. A simple steady-state kinetic model was developed based on the initial rates of ATZ destruction, which could well describe the apparent pseudo-first-order rate constants (k(app), s(-1)) of ATZ degradation in these three processes. The specific roles of reactive species (i.e., HO·, SO4(-·), CO3(-·), and Cl2(-·)) under various experimental conditions were quantitatively evaluated based on their steady-state concentrations obtained from this model. Modeling results showed that the steady-state concentrations of HO· and SO4(-·) decreased with the increase of CO3(2-)/HCO3(-) concentration, and the relative contribution of HO· to ATZ degradation significantly decreased in UV/H2O2 and UV/HSO5(-) systems. On the other hand, the scavenging effect of HCO3(-)/CO3(2-) on the relative contribution of SO4(-·) to ATZ degradation was lower than that on HO·. The presence of Cl(-) (0.5-10 mM) significantly scavenged SO4(-·) but had slightly scavenging effect on HO· at the present experimental pH, resulting in greater decrease of k(app) in the UV/S2O8(2-) than UV/H2O2 and UV/HSO5(-) systems. Higher levels of Cl2(-·) were generated in the UV/S2O8(2-) than those in the UV/H2O2 and UV/HSO5(-) systems at the same Cl(-) concentrations. NOM significantly decreased k(app) due to its effects of competitive UV absorption and radical scavenging with the latter one being dominant. These results improve the understanding of the effects of water constituents for ATZ degradation in the UV-based oxidation processes.
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http://dx.doi.org/10.1016/j.watres.2015.05.019 | DOI Listing |
Int J Pharm
January 2025
College of Engineering, Virginia Commonwealth University, 601 West Main Street, Richmond, VA 23284, USA. Electronic address:
Intranasal drug administration offers a promising strategy for delivering combination antiretroviral therapy (cART) directly to the central nervous system to treat NeuroAIDS, leveraging the nose-to-brain route to bypass the blood-brain barrier. However, challenges such as enzymatic degradation in the nasal mucosa, low permeability, and mucociliary clearance within the nasal cavity must first be addressed to make this route feasible. To overcome these barriers, this study developed solid lipid nanoparticles (SLNs) with varying PEGylation levels (0 %, 5 %, 10 %, and 15 % w/w of PEGylated lipid), co-encapsulated with Elvitegravir (EVG) and Atazanavir (ATZ) as an integrase and protease inhibitor, respectively.
View Article and Find Full Text PDFAm J Sports Med
January 2025
Department of Orthopaedic Surgery, Konkuk University Medical Center, Seoul, Republic of Korea.
Background: Multiple factors, such as muscle fatty infiltration (FI), tendon collagen content, and collagen arrangement, determine bone-tendon interface (BTI) healing after rotator cuff (RC) repair.
Purpose: To evaluate the effects of systemic administration of ezetimibe-atorvastatin (EZE/ATZ) combination on muscle FI and tendon collagen density and arrangement in an RC repair rat model.
Study Design: Controlled laboratory study.
Mol Inform
January 2025
Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093, Zürich, Switzerland.
Interpretability and reliability of deep learning models are important for computer-based drug discovery. Aiming to understand feature perception by such a model, we investigate a graph neural network for affinity prediction of protein-ligand complexes. We assess a latent representation of ligand binding sites and investigate underlying geometric structure in this latent space and its relation to protein function.
View Article and Find Full Text PDFPestic Biochem Physiol
December 2024
College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, PR China; Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, Northeast Agricultural University, Harbin 150030, PR China; Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, Northeast Agricultural University, Harbin 150030, PR China. Electronic address:
Atrazine (ATZ), a widely used triazine herbicide, has been shown to disrupt reproductive development in organisms. Melatonin (MLT) is a natural hormone and has been shown to have strong antioxidant properties. Due to its lipophilicity, it can cross biological barriers freely and act on germ cells directly.
View Article and Find Full Text PDFChemosphere
December 2024
School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China. Electronic address:
In electrochemical advanced oxidation processes (EAOPs), energy consumption cannot be ignored. In this work, Mn-Fe oxide/graphite felt (GF) cathodes were synthesized by in situ reduction and low temperature calcination. The obtained Mn-Fe oxide/GF was used as cathodes to activate peroxymonosulfate (PMS) for atrazine (ATZ) degradation in the EAOPs system.
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