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The Fe3O4 quantum dots anchored SnO2 nanofibers (Fe3O4 QDs/SnO2 NFs) and CdTe quantum dots anchored SnO2 nanospheres have been prepared via hydrothermal method. The characteristic structure of Fe3O4 QDs/SnO2 NFs and CdTe QDs/SnO2 NSs was analyzed using several techniques such as X-ray diffraction, transmission and scanning electron microscopy, UV–Vis and photoluminescence spectroscopy, and N2 adsorption–desorption instruments. The average diameters of Fe3O4QDs/SnO2 NFs and CdTe QDs/SnO2 NSs were 7.25 and 3.75 nm, respectively. BET surface area of Fe3O4QDs/SnO2 NFs and CdTe QDs/SnO2 NSs has been found 53.064 and 148.59 m2/g, respectively. The Fe3O4 QDs/SnO2 NFs and CdTe QDs/SnO2 NSs sample were used for removal and photo-catalytic of carcinogenic compounds such as ethyl methanesulfonate (EMS) and N-nitrosonornicotine (NNN). The Fe3O4 QDs/SnO2 NFs and CdTe QDs/SnO2 NSs demonstrates up to 90 and 56% photo degradation and adsorption activity against EMS and NNN solution, respectively. Additionally, cytotoxicity test indicated that the prepared catalyst has low cytotoxic influences. The antibacterial activity of prepared catalyst has excellent effect against Staphylococcus aureus, and Pseudomonas aeruginosa.

Finding the materials, which help to control the water pollution caused by organic and bacterial pollutants is one of the challenging tasks for the scientific community. We have developed and characterized a material, which can be used to remove of pollutant compound. ZnO quantum dots decorated CuO nanosheets composites have been synthesized using a hydrothermal method. The as synthesized ZnO QDs/CuO NSs composites were characterized by various techniques. The Crystallite sizes were to be obtained 12.5 and 3.2 nm for CuO NSs and ZnO QDs/CuO NSs composite. The energy band gap of the CuO NSs and ZnO QDs/CuO NSs composite are calculated to be 2.01 and 1.86 eV, respectively. The CuO NSs and ZnO QDs/CuO NSs composites are efficiently utilized for the photocatalytic degradation of Tetanus toxin (TeNT) as a target pollutant under UV and sunlight irradiation. The ZnO QDs/CuO NSs composites reveal excellent photocatalytic degradation of TeNT by degrading it up to 75% under UV and sunlight irradiation. The photocatalysis efficiency of ZnO QDs/CuO NSs composite is clearly higher than CuO NSs. The antibacterial activity of the CuO NSs and ZnO QDs/CuO NSs composites was also investigated on gram positive (Enterococcus faecalis) and gram negative (Micrococcus luteus) microbes.

For others wishing to develop Health Impact Assessment (HIA) guides (manuals) and to adjust them to conditions in their countries, we draw lessons from developing an HIA guide in Iran. We derive the lessons from our research comparing HIA guides found in the international literature and our experiences in adapting international experience to an HIA model for Iran that incorporates Iranian experts' opinions.

Drinking water resources may be contaminated with Ethidium Bromide (EtBr) which is commonly used in molecular biology laboratories for DNA identification in electrophoresis. Carbon nanotubes are expected to play an important role in sensing, pollution treatment and separation techniques. In this study adsorption of Ethidium Bromide on single-walled carbon nanotubes (SWCNTs) and carboxylate group functionalized single-walled carbon nanotube (SWCNT-COOH) surfaces have been investigated by UV–vis spectrophotometer. The effect of contact time, initial concentration and temperature were investigated. The adsorbents exhibits high efficiency for EtBr adsorption and equilibrium can be achieved in 6 and 3 min for SWCNTs and SWCNT-COOH, respectively. The effect of temperature on adsorption of EtBr by toward adsorbents shows the process in this research has been endothermic. The results showed that the equilibrium data were well described by the Langmuir isotherm model, with a maximum adsorption capacity of 0.770 and 0.830 mg/g for SWCNTs and SWCNT-COOH, respectively. The adsorption of EtBr on SWCNT-COOH is more than SWCNTs surfaces. A comparison of kinetic models was evaluated for the pseudo first-order, pseudo second-order models. Pseudo second-order was found to agree well with the experimental data.

The adsorption of ethidium bromide (EtBr) by single-walled carbon nanotubes (SWCNTs) and nanoscale of zero valent iron (NZVI) were investigated to assess its possible use as adsorbents. The effect of various factors, namely initial adsorbate concentration, adsorbent dosage, and contact time, were studied to identify adsorption capacity of SWCNTs and NZVI surfaces. The experiment demonstrated the maximum EtBr which was obtained at 5 min to attain equilibrium for SWCNTs and NZVI surfaces. Adsorption data were modeled with the Langmuir, Freundlichand, Temkin isotherms. Langmuir adsorption model was used for the mathematical description of the adsorption equilibrium, and the equilibrium data fitted very well with this model for both surfaces as adsorbents. The study showed that SWCNTs and NZVI surfaces could be used as new and efficient adsorbent materials for the removal of EtBr from aqueous solution. Also, the result showed that the SWCNTs were more effective than NZVI in the removal of EtBr from aqueous solution.

Removal thermodynamics and desorption studies of some heavy metal ions such as Co(II), Cu(II) and Pb(II) by polymeric surfaces such as poly 2-hydroxyethyl methacrylate (PHEMA) and copolymer 2-hydroxyethyl methacrylate with monomer methyl methacrylate P(MMA-HEMA) as adsorbent surfaces from aqueous single solution were investigated with respect to the changes in pH of solution, adsorbent composition, contact time and temperature in the individual aqueous solution. The linear correlation coefficients of Langmuir and Freundlich isotherms were obtained and the results revealed that the Langmuir isotherm fitted the experiment results better than Freundlich isotherm. Using the Langmuir model equation, the monolayer removal capacity of PHEMA surface was found to be 0.7388, 0.8396 and 3.0367 mg/g for Co(II), Cu(ΙΙ) and Pb(II) ions and removal capacity of P(MMA-HEMA) was found to be 28.8442, 31.1526 and 31.4465 mg/g for Co(II), Cu(ΙΙ) and Pb(II) ions, respectively. Changes in the standard Gibbs free energy (ΔG0), standard enthalpy (ΔH0) and standard entropy (ΔS0) showed that the removals of mentioned ions onto PHEMA and P(MMA-HEMA) are spontaneous and exothermic at 293-323 K. The maximum desorption efficiency was 75.26% for Pb(II) using 0.100 M HNO3, 70.10% for Cu(II) using 0.100 M HCl, 59.20% for 0.100 M HCl 63.67% Co(II).