Publications by authors named "G Kalogerakis"

Our study has thoroughly investigated the complete mineralization of toluene in water via heat-activated peroxydisulfate (PDS) by: (1) monitoring concentrations/peak areas of various intermediates and CO throughout the reaction period and (2) identifying water-soluble and methanol-soluble intermediates, including trimers, dimers, and organo-sulfur compounds, via non-target screening using high-resolution mass spectrometry. Increased temperature and PDS dosage enhanced toluene removal/mineralization kinetics and increased the rate/extent of benzaldehyde formation and its further transformation. Artificial groundwater and phosphate buffer minimally impacted toluene removal but significantly decreased benzaldehyde formation, indicating a shift in transformation pathways.

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Frequent use of persulfates as oxidants, for in situ chemical oxidation and advanced oxidation processes, warrants the need for developing a fast and efficient method for measuring persulfate concentrations in aqueous samples in the lab and on site. Here, we propose a modified method, based on Liang et al.'s (2008) spectrophotometric method, for measuring both peroxydisulfate (PDS) and peroxymonosulfate (PMS) in the aqueous samples.

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Plastic pollution in the marine environment is one of the foremost environmental problems of our time, as it affects wildlife and human health both directly and indirectly through the effects of contaminants carried by microplastics. This study investigates the temporal and spatial distribution of plastic pellets and fragments in sandy beaches along the coastline of Northern Crete, during 2013. Their densities varied throughout the year in each beach, with highest densities during the summer and towards the upper parts of the beaches.

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We improve the accuracy of numerical simulations for short fiber optical parametric amplifiers (OPAs). Instead of using the usual coarse-step method, we adopt a model for birefringence and dispersion which uses fine-step variations of the parameters. We also improve the split-step Fourier method by exactly treating the nonlinear ellipse rotation terms.

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In a cross-sectional study, oxidative stress in high vascular disease risk groups, ESRD (end-stage renal disease) and Type I diabetes, was assessed by measuring plasma protein carbonyls and comparing antioxidant capacity of HDL (high-density lipoprotein) as pertaining to PON1 (paraoxonase 1) activity and in vitro removal of LPO (lipid peroxides). ESRD subjects on haemodialysis (n=22), Type I diabetes subjects (n=20) without vascular complications and healthy subjects (n=23) were compared. Plasma protein carbonyls were higher in ESRD patients [0.

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