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The possibility of suspending radioactive particles during dust storms from Iraq and entering Iran has always been a concern. The aim of this study was to investigate the particulate matter concentration during dusty days and the effect of dust storm on the irradiation rate in the atmosphere of the city of Ilam (capital of Ilam province). The concentration of particulate matter and radiation dose in the study area were monitored between March 2012 and February 2013 (1 year). Sampling was done every 6 days for periodical days. For the dusty days, samples were gathered according to the forecast information of dust plum entrance by the meteorological organisation. The results showed that the average and standard deviation of PM10, PM2.5, and PM1 concentrations in the periodic sampling (every 6 days) were 76.9 ± 57.1, 17.5 ± 10.5, and 8 ± 4 μg/m3, respectively, and in the dusty days were286 ± 164.8, 54.4 ± 30.3, and 14.6 ± 6.5 μg/m3, respectively. During the study period, the concentration of PM10in 35 days were more than 150 μg/m3 (Dusty day), and June with 13 days was the highest number dusty days. The average radiation dose in normal and dusty days were 0.152 and 0.150 μSv/hr, respectively. The results of Mann–Whitney's test showed that there was no significant difference between measured radiation in normal and dusty days (P > 0.05). Spearman test showed that there was no significant correlation between radiation doses and PM (PM10, PM2.5, and PM1) (P > 0.05). The results of the study show that dust storms and its concentration intensity did not affect the amount of radiation in the Ilam atmosphere. Because of the high density of the uranium element and its rapid sedimentation near the emission sources, the entry of this contamination related to dust storms to Ilam has not been proven. [ABSTRACT FROM AUTHOR]

TiO2–FeZn nanocatalyst combined with sonolysis were used to activate peroxymonosulfate (PMS) as a highly efficient advanced oxidation process (US/TiO2–FeZn/PMS) for the decoloration of orange II dye (OII) and real textile wastewater. The characterization of the as-synthesized NPs was performed by SEM, FTIR, EDX and XRD analyses. Optimal experimental conditions of operational parameters were obtained: pH = 3, 15 mg/L initial OII concentration, 0.2 g/L PMS, 0.7 g/L nanocatalyst dosing, and 300 W ultrasonic power. The decolorization was observed to increase with increasing the dose of nanocatalyst and the ultrasonic power, and with decreasing pH (under acidic conditions). Under optimal experimental conditions, decolorization and COD removal of textile wastewater were 99.9% and 74.6%, respectively, at 40 min. The TiO2–FeZn/PMS/US as a novel process exhibited a higher removal of OII (95%) than TiO2 NPs/PMS/US process (54%). The OII removal efficiency by the different processes decreased in the following order: TiO2–FeZn/US/PMS > TiO2–FeZn/PMS > TiO2–FeZn/US > TiO2 /US/PMS > US/PMS > TiO2–FeZn > PMS > US. The recyclability study revealed that the process could be reused up to three consecutive cycles. The current US/nanocatalyst/PMS system was concluded to be an efficient, reusable and stable nanocatalyst for the oxidation of textile dyes. [ABSTRACT FROM AUTHOR]