BackgroundExtremely low frequency electromagnetic fields aren’t considered as a real carcinogenic agent despite the fact that some studies have showed impairment of the DNA integrity in different cells lines. The aim of this study was evaluation of the late effects of a 100 Hz and 5.6 mT electromagnetic field, applied continuously or discontinuously, on the DNA integrity of Vero cells assessed by alkaline Comet assay and by cell cycle analysis. Normal Vero cells were exposed to extremely low frequency electromagnetic fields (100 Hz, 5.6 mT) for 45 minutes. The Comet assay and cell cycle analysis were performed 48 hours after the treatment.ResultsExposed samples presented an increase of the number of cells with high damaged DNA as compared with non-exposed cells. Quantitative evaluation of the comet assay showed a significantly (<0.001) increase of the tail lengths, of the quantity of DNA in tail and of Olive tail moments, respectively. Cell cycle analysis showed an increase of the frequency of the cells in S phase, proving the occurrence of single strand breaks. The most probable mechanism of induction of the registered effects is the production of different types of reactive oxygen species.ConclusionsThe analysis of the registered comet indices and of cell cycle showed that extremely low frequency electromagnetic field of 100 Hz and 5.6 mT had a genotoxic impact on Vero cells.

The main result and characterizing aspect of the research consists of the effectiveness of novel ZnO-linen fibrous composites synthesized by means of hydrothermal deposition of zinc oxide onto linen fibers, with the assistance of two surfactants. This has a direct implication on the relationship between the morphological, structural and chemical attributes and water vapor sorption-desorption behavior. Methodology consists of the hydrothermal synthesis of zinc oxide onto linen fibrous substrates previously grafted with MCT-β-CD (MonoChloroTriazinyl–β-CycloDextrin) via a hydrothermal process. The morphological, structural and chemical properties of the samples were examined, in terms of a co-assisted investigation system: SEM images for the morphology, EDX analysis for surface composition, FTIR spectroscopy and X-ray diffractometry for structural samples features. Dynamic vapor sorption (DVS) analysis will complete this study. According to the results provided by the characterization technique, the uniformity of the fabric coated with ZnO powder hydrothermally synthesized with assistance of CTAB (Cetyl TrimethylAmmonium Bromide) is better than that of ZnO powder hydrothermally synthesized in the presence of Pluronic P123 and possesses good washing fastness. X-ray diffraction results have indicated that the composites exhibited a more ordered structure and higher water vapor sorption-desorption capacity (obtained by DVS analysis) compared with those of the reference fibrous linen supports.

The utilization of classical ceramic technology for ferrite preparation permits to obtain strontium hexaferrite with big crystals, of micrometer size, with a smaller coercive force than the hexaferrite with submicron crystals. In this work the strontium hexaferrite was obtained with submicron crystals, by hot reduction of the hexaferrite obtained through ceramic technology in CO atmosphere, followed by the thermal re-oxidization in air. The effects of treatment in CO atmosphere and of the re-calcination treatment on the magnetic and electric properties of the strontium hexaferrite were investigated.

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Two environmentally friendly organics (ethylenediaminetetraacetic acid, EDTA and its easier biodegradabe isomer, ethylenediamine-N, N′-disuccinic acid, EDDS) were used to dope calcium carbonate (CC) nanoparticles intending to increase their adsorptive properties and evaluate adsorption performance (uptake capacity and removal efficiency) for the persistent Reactive Yellow 84 azo dye. Easily synthesized nanomaterials were fully characterized (morphology and size, mineralogy, organic content, surface area, pore size and hydrodynamic diameter). RY84 removal was performed using two consecutive processes: photodegradation after adsorption. The CC-EDTA particles were most efficient for dye removal as compared to the plain and CC-EDDS particles. Adsorption kinetics and isotherms were considered for the CC-EDTA system. 99% removal occurred via adsorption on 1 g/L of adsorbent at 5 mg/L dye concentration and pH of 8 and it decreased to 48% at 60 mg/L. Maximum uptake capacity as described by Langmuir is 39.53 mg/g. As post-adsorption, under UVA irradiation, in the presence of 40 mmol/L H2O2, at dye concentration of 10 mg/L the highest degradation was 49.11%. Substantial decrease of adsorption (ca. 4 times) and photodegradation (ca. 5 times) efficiencies were observed in wastewater effluent as compared to distilled water. The results have important implications to wastewater treatments and appropriate decisions making for the choice of treatment process, process optimization and scaling up to pilot and industrial levels.

Aspartic acid stabilized iron oxide nanoparticles (A-IONPs) with globular shape and narrow size distribution were prepared by the co-precipitation method in aqueous medium. A quantum-mechanical approach to aspartic acid optimized structure displayed negative charged sites, relatively high dipole moment, and hydrophilicity, which recommended it for interaction with iron cations and surrounding water electrical dipoles. A-IONPs were characterized by TEM, XRD, ATR-FTIR, EDS, DSC, TG, DLS, NTA, and VSM techniques. Theoretical study carried out by applying Hartree-Fock and density functional algorithms suggested that some aspartic acid properties related to the interaction can develop with nanoparticles and water molecules. The results of experimental investigation showed that the mean value of particle physical diameters was 9.17 ± 2.2 nm according to TEM image analysis, the crystallite size was about 8.9 nm according to XRD data, while the magnetic diameter was about 8.8 nm, as was determined from VSM data interpretation with Langevin’s theory. The A-IONP suspension was characterized by zeta-potential of about −11.7 mV, while the NTA investigation revealed a hydrodynamic diameter of 153.9 nm. These results recommend the A-IONP suspension for biomedical applications.

This work was dedicated to the preparation of a barium hexaferrite using the glass crystallization method. The glass flakes were treated at temperatures ranging between 550• C and 750• C. The investigation carried out by X-ray diffraction revealed the phase composition and the mean crystallite size. By means of the scanning electron microscopy, the crystallite shape and average size were established. The electric and magnetic properties were investigated at room temperature by means of a Solartron 1260A impedance/gain phase analyzer and a vibrating sample magnetometer. The optimum heat treatment was established to obtain the maximum coercivity of the barium hexaferrite.

In the textile finishing and dyeing industries, the total volume of water consumed is around 150 millions tons/year, and thus very large quantities of water are processed and produced as wastewater by textile plants. Quality indicators of textile wastewaters, like BOD and COD, have values which, in some cases, exceed 5 times the maximum concentration value (allowed by the national quality standards). One of the greatest concerns in wastewater treatment of a textile effluent is the colour, not only as an aesthetic problem, but also as a pollution problem. Dyes and pigments from the printing and dyeing operations are the principal sources of colour in this type of effluents. Dyestuffs are usually highly structured polymers with low biodegradability and their concentration in the effluent is around 10 mg/L. Recovery, recycling and reuse must be effective tools in minimizing pollutant releases in the environment. Usually, ultrafiltration is used as a single step in advanced wastewater treatment, either for internal or external recycling. The aim of this study is to obtain higher removal efficiencies of contaminants using a 2 step advanced treatment: ultrasonication, followed by ultrafiltration. The experiments were done on a laboratory scale installation and the dyes used in the experiments are Reactive Red 243 and Reactive Violet 5. Ultrasonication destroys most of the dye molecules and ultrafiltration retains the remaining dye molecules and suspended solids and colloids formed in the previous process. During the experiments it was observed that the suspended solids and colloids interfere with the spectrophotometrical method used to determine dye concentration, if the ultrafiltration membrane is not selected properly. Solids, produced after ultrasonication, were dried and analysed using SEM and XPS techniques. Removal efficiencies of 80% (expressed as colour extinction) were obtained, so as it may be concluded that the combination of ultrasonication-ultrafiltration may be further investigated for the advanced treatment and recycling of textile wastewater.