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In the present work a combined process is proposed for recovery of metallic copper from industrial electroplating wastewaters comprising electrocoagulation, acidic digestion and electrowinning. The wastewater with the initial Cu2+ ion concentration of 92 mg/L was first subjected to electrocoagulation where it successfully decreased under the upper allowed limit of 2 mg/L. Then, the obtained electrocoagulation sludge was treated with sulfuric acid for digestion and with caustic soda to reach pH 4.8 for precipitation and separation of insoluble aluminum hydroxide, whereas Cu2+ ions remain in solution. Finally, pure metallic copper was produced by electrowinning from the obtained concentrated Cu2+ ions solution. The work proposes the possibility of effectively treating toxic industrial electroplating wastewater accompanied by recovery of significant amounts of valuable pure metals, such as copper 12 3 1 4

Over the last decade there has been a significant boost towards the use of electronic cigarettes (e-cigarettes), especially among youth. Different concentrations of propylene glycol (PG) or vegetable glycerin (VG), flavors and nicotine are mixed in plastic cartridges and commercially offered or privately produced by the vapers. During vaping, a mixture of air and vapors is inhaled to the lungs. Since the ingredients of the e-cigarettes are not burned but vaporized (heated), fewer chemicals are emitted. The levels of potentially toxic compounds (e.g. volatile organic compounds (VOCs), particulate matter (PM), metals, radicals, nitrosamines, etc.) emitted from vaping appear to be lower compared to that of tobacco smoking (from combustible cigarettes). Nevertheless, measurable toxic elements and VOCs are still released (e.g. acetaldehyde, formaldehyde, acrolein, benzene, etc.) along with other volatiles associated with e-liquid flavoring and device variability with PG and VG. The wide range of available flavors at various purities along with the heating temperature are important parameters affecting the evolution of VOCs and aerosols. There is lack of standardized short- and long-term epidemiological medical data (chronic exposure) on e-cigarettes effects to users, non-users and the human micro-environment (second- or third-hand exposure). Therefore, the potential health, safety and environmental effects of vaping are reviewed, examined and discussed.

The proposed photovoltaic electrochemical (PV-EC) process combines autonomous and environmentally friendly photovoltaic solar energy with the capability of the combined electrocoagulation/electrooxidation process to effectively remediate toxic olive mill wastewaters and simultaneously produce electrolytic hydrogen. The photovoltaic array can be connected directly to an electrochemical reactor without batteries increasing, in this way, system sustainability and eliminating the environmental threat of poor battery disposal management. The PV-EC system is proved versatile according to the instantaneous solar irradiation by adjusting the wastewater flow rate to the current intensity supplied by the photovoltaic array. Operating parameters affecting the efficiency of the proposed process, such as wastewater flow rate, conductivity, current density, electroprocessing time and solar irradiance were studied and optimal conditions were investigated. The experimental results showed that the initial COD of 21000 mg/dm3 and turbidity of 162 NTU of the olive mill waste sample, were effectively reduced to 122 mg/dm3 and 0 NTU, respectively, after treating the wastewater by both, batch wise and continuously operated electrocoagulation and electrooxidation or combination of the two processes. The proposed process is a safe method for effective treatment of toxic and recalcitrant wastes, such as oily olive mill wastewaters, especially for applications in remote and isolated locations with lack of electric grid. 98 5 377 381

The current study investigated the association between Machiavellianism and children’s peer interactions in the playground using observational methods. Primary school children (N = 34; 17 female), aged 9 to 11 years, completed the Kiddie Mach scale and were observed in natural play during 39 recesses (average observed time = 11.70 hours) over a full school year. Correlations for boys revealed that Machiavellianism was related to more time engaging in direct and indirect aggression, being accepted into other peer groups, and accepting peers into their own social group. Correlations revealed that for girls, Machiavellianism was associated with lower levels of indirect aggression, less time being accepted into other groups and less time accepting and rejecting other children into their own group. This preliminary pilot study indicates that Machiavellianism is associated with children’s observed social behaviour and aims to promote future observational research in this area

Reaction of the N,N-disubstituted bis(hydroxylamino) ligand 2,6-bis[hydroxy(methyl)amino]-4-morpholino-1,3,5-triazine (H(2)bihyat) with cis-[(MoO2)-O-VI(acac)(2)] in tetrahydrofuran resulted in isolation of the mononuclear compound cis-[(MoO2)-O-VI(bihyat)] (1). The treatment of (Na2MoO4)-O-VI center dot 2H(2)O with the ligand H(2)bihyat in aqueous solution gave the dinuclear compounds cis-[(Mo2O4)-O-VI(bihyat)(2)(H2O)(2)] (2) and trans-[(Mo2O4)-O-VI(bihyat)(2)(H2O)(2)] (3) at pH values of 3.5 and 5.5, respectively. The structures for the three molybdenum(VI) compounds were determined by X-ray crystallography. Compound 1 has a square-pyramidal arrangement around molybdenum, while in the two dinuclear compounds, each molybdenum atom is in a distorted pentagonal-bipyramidal environment of two bridging and one terminal oxido groups, a tridentate (O,N,O) bihyat(2-) ligand that forms two five-membered chelate rings, and a water molecule trans to the terminal oxido group. The dinuclear compounds constitute rare examples containing the {(Mo2O2)-O-VI(mu(2)-O-2)}(4+) moiety. The potentiometry revealed that the Mo(VI)bihyat(2-) species exhibit high hydrolytic stability in aqueous solution at a narrow range of pH values, 3-5. A subtle change in the coordination environment of the five-coordinate compound 1 with ligation of a wealdy bound water molecule trans to the oxido ligand (1w) renders the equatorial oxido group in 1w more nucleophilic than that in 1, and this oxido group attacks a molybdenum atom and thus the dinuclear compounds 2 and 3 are formed. This process might be considered as the first step of the oxido group nucleophilic attack on organic substrates, resulting in oxidation of the substrate, in the active site of molybdenum enzymes such as xanthine oxidase. Theoretical calculations in the gas phase were performed to examine the influence of water on the dimerization process (1 -> 2/3). In addition, the molecular structures, cis/trans geometrical isomerism for the dinuclear molybdenum(VI) species, vibrational spectra, and energetics of the metal-ligand interaction for the three molybdenum(VI) compounds 1-3 have been studied by means of density functional theory calculations. Inorg Chem