Articles
RSC Advances (20462069)14(24)pp. 16801-16808
Cobalt ferrite (CoFe) nanoparticles (NPs) with appropriate physicochemical and biological properties have attracted great attention for biomedical applications. In the present study, chitosan-coated mesoporous CoFe (CoFeCH) NPs were synthesized using a facile one-step hydrothermal method and fully characterized using FE-SEM, EDS, BET, FTIR spectroscopy, DLS, TGA, XRD, and VSM. The spherical, highly colloidal, and monodispersed CoFeCH NPs with an average hydrodynamic size of 177.9 nm, PDI of 0.238 and zeta potential value of −33 represented a high saturation magnetization value of 59.37 emu g−1. N2 adsorption-desorption analysis confirmed the mesoporous structure of CoFeCH NPs with a type IV isotherm, calculated specific surface area of 89.583 m2 g−1 and total pore volume of 0.3668 cm3 g−1. CoFeCH NPs exhibited high antibacterial effects on S. aureus and E. coli, comparable with standard antibiotics, while CH-coating led to higher biocompatibility of CoFe NPs on human cells in vitro. CoFeCH NPs also showed significant peroxidase activity with a Km value of 14.37 and specific activity of 0.632 mmol min−1. CoFeCH NPs were successfully used as a MRI contrast agent with an R2 value of 91.3 mM−1 s−1. The overall results indicated the high potential of synthesized CoFeCH NPs by the present method for biomedical applications, especially as an antibacterial and MRI contrast agent. © 2024 The Royal Society of Chemistry.
Environmental Earth Sciences (18666299)78(13)
Urmia Lake is one of the greatest salt lakes in the world and is located in the uppermost northwestern regions of Iran. In this study, in addition to trace elements, activity concentration of natural (238U, 232Th and 40K) and artificial (137Cs) radioisotopes are determined in soil and sediment specimens collected from the Urmia Lake shore by adopting gamma ray spectrometry method. The samples are analyzed for trace elements including heavy metals using atomic absorption and ICP-MS techniques. The activity concentration levels were determined for 238U (from 8 to 48 Bq kg−1), 232Th (from 7 to 64 Bq kg−1), 40K (from ≤ MDA to 631 Bq kg−1) and 137Cs (from ≤ MDA to 22 Bq kg−1) with the minimum detectable activity (MDA) of 5, 4, 63 and 4 Bq kg−1, respectively. It seems that except for the cadmium, all of the elements belong to uncontaminated to low contaminated soils group. The least correlation between 137Cs and other elements distribution in the area, confirms its anthropogenic man made source. Based on the cluster and factor analysis methods of data processing, 238U, 232Th and 40K belong to a similar group which in addition to their low geo-accumulation indexes can point to their geogenic sources, related to potassic volcanic rocks. Rare earth elements studies revealed that the main geochemical features of the sediment samples of the lake are affected by the intermediate to felsic Cenozoic volcano-plutonic rocks of the region. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
Advances In Environmental Technology (24764779)4(3)pp. 155-161
This study investigated different methods of controlling the fat, oil and grease (FOG) in sewer systems. A comprehensive control program was developed for the city of Mashhad (Iran) to maintain its sewer system and prevent blockages. The control program consisted of three parts: 1) fat, oil and grease source control, 2) sewer system modification, and 3) preventive maintenance. This program included guidelines for food service establishments, which are the major sources of (FOG). Food service establishments must implement better management practices to reduce (FOG) from entering the facility drain and install grease removal devices. As a part of preventive cleaning, the performance of several surfactants was evaluated as a cleaning agent. A 50:50 mixture (10 v. % in water) of two industrial surfactants, one containing monoethyl amine and sulfonated lauryl alcohol and one containing nonylphenol ethoxylate and potassium hydroxide, had the best performance and removed 80 % of the fat. Response Surface Methodology was used to determine the optimum conditions for the surfactant. The optimum conditions were a contact time of 36 h, shaking rate of 30 rpm and surfactant concentration of 12.5%. The second part of the program consisted of removing dead zones and increasing wastewater velocity in the sewer lines to enhance the hydraulic condition of the sewer system and decrease fat deposition. Finally, a detailed and well-defined control program could solve FOG problems in sewer systems. © 2018, Iranian Research Organization for Science and Technology. All rights reserved.
Zare, M.R.,
Kamali, M.,
Fallahi kapourchali, M.,
Bagheri, H.,
Khoram bagheri, M.,
Abedini, A.,
Pakzad, H.R. Environmental Science and Pollution Research (09441344)23(4)pp. 3285-3299
Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of 235U, 226Ra, 232Th, 40K, and 137Cs in sediment samples ranged between 1.05 ± 0.51–5.81 ± 0.61, 18.06 ± 0.63–33.36 ±.0.34, 17.57 ± 0.38–45.84 ± 6.23, 371.88 ± 6.36–652.28 ± 11.60, and 0.43 ± 0.06–63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36–5.97, 22.71–38.37, 29.27–42.89, 472.66–533, and 1.05–9.60 Bq/kg for 235U, 226Ra, 232Th, 40K, and 137Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland. © 2015, Springer-Verlag Berlin Heidelberg.
