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a b s t r ac tIt is hard to remove malachite green from aquatic environments due to its low degradability and other features. Based on the effect of manganese on physical and chemical characteristics of scoria, the aim of this study is to evaluate the manganese-coated pumice performance in removing malachite green (MG) from aquatic environments. Response surface methodology (RSM) based on the central composite designs (CCD) was used to assess the effects of independent variables including pH (3, 5, 7, 9, and 11), adsorbent dosage (0.2, 0.5, 0.8, 1.1, and 1.4 g/L), contact time (15, 30, 45, 60, and 75 min), and constant concentration of the dye (85 mg/L) on the response function and the best response values were predicted. The results indicated that the dye removal increases with increasing the pH value, absorbent dosage and contact time, whereas MG concentration has an antagonistic effect on sorption system. Moreover, the optimum dye removal efficiency (99.9%) was achieved in pH = 11, adsorbent dose = 1.4 g/L, and contact time = 75 min. The adsorption process fitted well with the Langmuir model which, indicated the presence of heterogeneous sites for to adsorption MG dye and also this process followed the pseudo-second-order model. According to the results, the modified pumice with manganese could be successfully used for MG adsorption in the aqueous solution rather than natural scoria due to wide chemical changes of adsorbent structure.

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Background: Sleep disorders are among important challenges for health policymakers due to its high prevalence and very high economic burden. Effect of air and noise pollutions on sleep quality and disorders has been proposed. Objectives: In the present study, the geographical distribution of people diagnosed as insomnia in Sleep Disorders Research Centers (SDRC) in the western Iran was investigated. Methods: All patients with primary insomnia who diagnosed by polysomnography (PSG) in SDRC between 2011 to 2019 were recruited. The postal addresses of participants specified by a geographical coordinate represented longitude, latitude, and vertical position. These geographical coordinates converted to Geographic Information System (GIS) and addresses were located on the map. Then participants were divided into noisy and quiet environment groups based on their distance from highways, boulevards, and streets. Subjective and objective sleep characteristics were compared between these two groups by independent sample t-test or U Mann Whitney test using the Statistical Package for the Social Sciences (SPSS) version.22. Results: Of 78 participants, 47 were from Kermanshah city, 19 were from counties of Kermanshah province, and 14 participants were from Kurdistan, Ilam, Hamedan, Lorestan, Khuzestan and Tehran provinces. The location of all participants was presented on GIS maps. Result didn’t indicate any significant differences in sleep characteristics between the two noisy and quiet environment groups. Conclusions: Most insomniac patients investigated in the SDRC come from Kermanshah city. Patient with insomnia may reach a level of the pathophysiological condition in sleep-wake regulation systems that lead to problematic sleep characteristics independently from environmental noise.

Introduction: 2-Chlorophenols are toxic and hazardous pollutants in industrial effluents and sewage. Due to their toxicity and instability, these compounds are known as pollutants with a high environmental profile, even at low concentrations. This study aimed to determine the efficiency of activated peridates with magnesium oxide nanoparticles in the presence of ultraviolet waves for removing 2-chlorophenol from aqueous solutions. Methods: In this experimental study, the photochemical analysis of 2-chlorophenol was performed in a 2.5-liter Discontinuous cylindrical reactor. A 55-watt low-pressure mercury lamp was used to produce ultraviolet waves with a wavelength of 254 nm. The parameters affecting the absorption process (pH 3 to 11), the dose of nanoparticles (0 to 1.5 mmol/L), 2-chlorophenol concentration (0.22 to 1.76 mmol / L), Peridat concentration (0 to 4 mmol/L), and contact time (0 to 60 minutes) were investigated. Results: In the combined process of peridate activation with magnesium oxide nanoparticles in the presence of ultraviolet light (UV/PI/MgO), the maximum removal rate of 2-chlorophenol was at pH 7, the concentration of peridates was 4 milliules per liter, the concentration of nano magnesium oxide particle 1 milliliter Mole per liter and initial regimen of 0.44 mM / L of 2-chlorophenol were obtained. In these conditions, about 85% of 2-chlorophenol was removed passing over 60 minutes. . Also, by increasing the initial concentration of adsorbent and adsorbate, the efficiency of removing 2chlorophenol decreased. Conclusions: Magnesium oxide nanoparticles are suitable for the removal of 2chlorophenol and are efficient. The pH value equaling 7, the peridate concentration of 4 mmol/L, magnesium oxide nanoparticles with 0.44 mmol/L concentration and a 60 minute time are the optimum states by 2-chlorophenol.