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Navicula algae are major contributors to water pollution, including its taste and odour. In this study, new Co-MOF/PVA polymeric fibrous nanostructures were synthesized by incorporation of Co-MOF in the PVA fibrous network using ultrasound-assisted electrospinning route. The results obtained from the different analyses showed that the physicochemical properties of the final product were improved compared to pure Co-MOF nanostructures. It seems that the type of synthesis route, as well as the incorporation of nanostructures, has a great effect on the properties of the final Co-MOF/PVA samples. Due to the properties of the products such as high thermal stability (273 ∘ C) , narrow crystalline size (35 nm), and homogenous morphology, the Co-MOF/PVA fibrous nanostructures samples have been used as a novel candidate for removing Navicula Algae from drinking water. The 2k−1 experimental design results showed that the rate of algae removal by these nanostructures is about 98%. To achieve the desired performance of the Co-MOF/PVA nanofibrous network, RSM was used. This optimization methodology facilized the experimental conditions of the removal rate of about 99.96%. [ABSTRACT FROM AUTHOR]

Background and Aims: Bioaerosols are airborne particles that contain bacteria, viruse, and fungi. Human show different reactions to bioaerosols. This study aimed to determine the density of bacterial particles cultivable in the inside and outside air of kindergardens in Birjand, Iran. Materials and Methods: This study was performed based on a descriptive-analytical and cross-sectional research approach. Birjand was divided into five regions based on their geographical location, and six kindergardens were randomly selected. The sampling was performed in the morning shift from all six selected kindergartens. Additionally, triptic soy agar was used as the culture medium, and the sampling was performed at a flow rate of 28.3 L/Min for 35 min at a distance of 0.8 to 1 M above the ground in the center of each class. The data were analyzed in SPSS software (version 16) through the Mann-Whitney and Kruskal-Wallis statistical tests. A p-value less than 0.05 was considered statistically significant. Results: According to the results, the highest mean bacterial and microbial load and suspended particles were obtained at 3.83±8.04 CFU/m3 and 196.13±382.54 CFU/m3 in February and March, respectively. There was no significant relationship among bacterial density, suspended particles, and temperature (P>0.05). However, a significant relationship was observed between the bacterial density and total suspended particles (P<0.05). There was also a significant relationship between the amount of suspended particles (PM1, PM2.5, PM10) and the environment inside and outside the kindergardens (P<0.05). Conclusion: It is possible to determine the concentration of bacterial contamination in terms of quantity, type of identified species, and the amount of airborne particles to prevent the adverse health effects. [ABSTRACT FROM AUTHOR]

TetrabromobisphenolA is a well-known member of the brominated flame retardant group and is widely used as a highly effective fire-retardant additive in electronic and electrical equipment. TBBPA is commonly found in various environmental sources and can be harmful to human health. This study presents a simple approach to preparing a magnetic nanocomposite, offering a straightforward method that results in consistent quality and low resource consumption. The nanocomposite has a high surface-to-volume ratio for the removal of tetrabromobisphenolA. Various characterization techniques, including XRD, FTIR, EDX, FESEM, VSM, TEM, and BET analyses were used to characterize the Fe–S nanoparticles and Fe–S/CuS. The results showed that Fe–S/CuS nanocomposite successfully removed over 97% of the initial TBBPA (15 mg L−1) under optimized conditions determined by RSM, such as a contact time of 15 min, pH of 7, Fe–S/CuS nanocomposite dosage of 0.69 g L−1, and salt concentration of 0.10%. The RSM analysis provided a second-order polynomial model with a confidence level of 93% (F = 29.58; p < 0.0001) to predict the TBBPA removal efficiency at various concentrations. In the adsorption kinetic studies, the second-order kinetic model provided the best fit for the experimental data. Additionally, Fe–S/CuS nanocomposite shows great potential for practical applications and environmental remediation efforts, making it a valuable asset for real-sample use in environmental settings. [ABSTRACT FROM AUTHOR]

The current work explores the photocatalytic degradation of tetracycline utilizing ZIF-8 grafted with MnFe 2 O 4 through a facile green approach. The complete degradation was achieved at optimized circumstances (pH = 9, catalyst concentration = 0.5 g/L, contact time = 180 min, and 20 mg/L of tetracycline dose). The photocatalytic decontamination reaction of the as-made catalyst was more adherence to the pseudo-first-order model. Recycling experiments demonstrated the excellent stability of the MnFe 2 O 4 /ZIF-8 composite after six regeneration runs. Furthermore, the as-constructed composite can simultaneously eliminate tetracycline, COD, and TOC from real wastewater by 84%, 65%, and 50%, respectively, revealing its robust potential in addressing water contamination concerns. [Display omitted] • New Green magnetic MnFe 2 O 4 /ZIF-8 nanocomposite was synthesized and characterized. • Completed degradation of Tetracycline with MnFe 2 O 4 /ZIF-8/UV photocatalytic process. • Hydroxyl radicals are the primary oxidative agents involved in the decontamination. • The fabricated catalyst revealed high stability after six runs. • The biodegradability rate of wastewater was enhanced after the purification. [ABSTRACT FROM AUTHOR]

Keeping the efficiency of adsorbents in view with devising new solid phase extraction (SPE) methods, this study was aimed at preparation and examination of a new beneficial adsorbent for heavy metal ions. A suitable extractant, 1,8-Dihydroxyanthraquinone (Danthron), was impregnated onto MWCNTs and, firstly, the adsorption properties of Danthron-impregnated MWCNTs (Danthron/MWCNTs) were checked towards some targeted metal ions, i.e. Pb2+, Cu2+, Zn2+, Cd2+, Co2+, and Ni2+ ions. Langmuir isotherm fitted with equilibrium data, kinetic studies vouchsafed the obedience of experimental data from pseudo-second-order model, and thermodynamic appraisals revealed the endothermic nature of adsorption process. Secondly, provided with good sorption properties of the adsorbent, a mini-column packed with Danthron/MWCNTs was recruited for pre-concentration of the interested analytes prior to their determination by inductively coupled plasma (ICP) instrument. The detection limits were in a range between 0.301 and 0.016 µg·L−1 and the new SPE method showed a high efficiency in tackling analysis of natural waters, herbal infusion samples, and certified reference materials. Overall, the results vouchsafed that Danthron/MWCNTs can be regarded as a suitable adsorbent for preconcentration of the targeted metals. Danthron-impregnated MWCNTs show good properties for adsorption of some metal ions and have an excellent performance when are used for solid-phase extraction and determination of trace level of these metal ions. [Display omitted] • Carbon nanotubes were impregnated with 1,8-dihydroxyanthraquinone (Danthron). • Danthron-impregnated carbon nanotubes were recruited for adsorption of metal ions. • Adsorption properties of the adsorbent for some heavy metal ions was scrutinized. • It was used as a support for solid phase extraction of the targeted metal ions. • Selectivity was shown by analyzing real samples and certified reference materials. [ABSTRACT FROM AUTHOR]

In this study, Cu and Zn-metal organic framework nanostructures were synthesized in the shortest possible time and with high efficiency using the ultrasonic assisted reverse micelle (UARM) method. Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and nitrogen adsorption techniques were used to characterize the synthesized samples. According to the BET method, the Cu-MOF sample has 410 m2/g of surface area and a volume pore of 0.021 cm3, whereas the corresponding values for Zn-MOF were 1145 m2/g and 0.097 cm3, respectively. The physicochemical properties of the products were thoroughly investigated, and the adsorbent dosage, temperature, and pressure for preparing samples with experimental parameters were 0.05 mg, 25.0 °C and 5.0 bar, respectively with high adsorption efficiency. Fractional factorial design and response surface methodology were used to design and control the best conditions. It could be used as an adsorbent in the adsorption of arsine gas. [ABSTRACT FROM AUTHOR]

Removal of cadmium ions from an aquatic solution was investigated by low-cost adsorbents and compared when modifying them by Fe-S nanoparticles. Nanocomposites were synthesized by a new experimental method under simple and inexpensive procedure by Fe-S nanoparticles, which possessed good characteristics of the surface area and magnetic property. These nanocomposite adsorbents removed cadmium at larger percentages than pure adsorbents. Iron filings had only a minor effect on the removal of cadmium, but when they were modified with Fe-S nanoparticles, the adsorption rate reached over 98.5%. Under operating conditions of pH 7, a concentration of 3 ppm, and a flow rate of 5 ml/min, the highest cadmium adsorption in water was caused by the iron nanocomposite. Display Omitted [ABSTRACT FROM AUTHOR]