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For the analysis of polyoxometalate functionality (POM), a bioassay was developed in order to determine the effect of the functionalized porous ceramic granule (with POM) on the germination of tomato plantlets (Lycopersicon esculentum) and cowpea (Vigna unguiculata). After 3 days of incubation under dark conditions at room temperature in the case of cowpea seeds and 6 days in the case of tomato seeds, the germination process was calculated and the radicle and hypocotyl growths of the obtained plantlets were biometrically assessed in each of the treatment variants respectively, in the control sample (distilled water). When the percentage of germination was assessed, only the seeds with a germ larger than 2 mm in length were considered germinated. Analyzing the influence of the suspensions added to the germination substrate, it was found that, in case of the cowpea, after the seed germination time (3 days), the supernatant treatments obtained by suspending 5g of porous ceramic granules functionalized with POM in 100 ml of distilled water for 2 hours generally stimulated germination percentage, this being 100% in most experimental variants. Only at POM2, the maximum concentration, the germination value was below 100%, but it was above that of the untreated control sample (AA). In case of tomatoes, the percentage of germinated plantlets was between 96-100% after 6 days of incubation. And in the case of cowpea, the supernatant treatments obtained by suspending 5 g of porous ceramic granules functionalized with POM in 100 ml of distilled water for 2 hours generally stimulated the germination percentage. Only treatment variants in which 10% supernatant (2 ml to 20 ml medium) from POM2 supernatant was added to the substrate, it showed a germination of less than 100%, but also an increase compared to the untreated control sample (AA) and even towards the control sample represented by the non-functionalized ceramic supernatant. Regarding the size of the hypocotyls and radicle, those were biometrically assessed by measuring at the time of full germination, after three days in the case of the cowpea and 6 days in the case of tomatoes. These morphological analyzes demonstrate a significant biostimulation effect of nutrients released into the supernatant obtained by suspending 5g porous ceramic granules functionalized in 100 ml distilled water for 2 hours. The proposed bioassay are quick, easy to achieve, and represent the optimal way of ensuring the quality required for the reproducibility of the polyoxometalate functionality which were included in the ceramic granules. For both types of seed used, the functionalized ceramics had a similar behavior. [ABSTRACT FROM AUTHOR] more...

Cementation is one of the most effective, eco-friendly and economically advantageous techniques for removal of valuable and / or toxic metals from industrial wastewaters. Copper is among the most prevalent and valuable metal used in industry. The present study investigates an eco-friendly recovery method for the copper ions present in synthetic wastewater, by cementation, using scrap iron and no energy consumption. It was evaluated the impact on copper cementation yield, caused by the fallowing parameters: (a) initial copper concentrations, (b) pH values and (c) contact time. Experiments were carried out at room temperature and without energy consumption or stirring. The data indicated high cementation yields (76.5 - 95.6%) after a contact time of three days in the case of diluted solutions (0.5% and 1%), and high cementation yields (81.2 - 88.4%) after a contact time of one day in the case of concentrate solutions (3%). [ABSTRACT FROM AUTHOR] more...

Polyoxometalates (POMs) are discrete, anionic metal-oxygen clusters of early d bloc metal ions in high oxidation status (e.g. MoVI, WVI) with a very large structural and compositional variety, leading to interest in many different areas (catalysts in homogeneous and heterogeneous catalytic oxidation of organic compounds or biochemical reactions, activity in enzymatic redox processes, as antitumoral, antibacterial and antiviral treatments etc). An important subclass of POMs is the {XMo6O24} structure type, Anderson-Evans structure, in which an octahedral XO6 hetero group is surrounded by six edge-shared MoO6 octaedra. In the literature almost all syntheses of the subclass Anderson-Evans polyanions are of the hydrothermal type, yielding crystalline compounds in low yields and, after one or two recrystallizations, the obtained crystals are good for single X-ray investigation. The major problems of these syntheses are low reproducibility and low yields (14 - 35%). Here, we report two green methods of synthesis of {XMo6O24} Anderson-Evans polyanions, where X = Cr(III), Mn(II), Co(II), Ni(II) and Cu(II), in one-pot procedure, under conventional „open beaker" conditions, in aqueous solutions, controlling the final pH and without heating. Slow evaporation at room temperature for Cr(III) and Mn(II) compounds for 2-6 hours led to the formation of well formed crystals and excellent yields (70-75%). Slow evaporation in a refrigerator at 60C for Co(II), Ni(II) and Cu(II) compounds for 2-5 days led to the formation of small crystals and good yields (60-65%). The two green methods described in this paper are simple, rapid, reproducible, inexpensive, and the resulting compounds are crystalline and high yields (60-75%). The molecular formula of Anderson-Evans polyanions were determined by elemental and thermo-gravimetric analysis, UV-Vis and FTIR spectroscopy. [ABSTRACT FROM AUTHOR] more...

Baia Mare is located in the north-west of Romania and is one of the most representative mining areas from this country. A total of 90 sediments samples were collected from 18 important points from Baia Mare town and surrounding areas during one year (December 2013, March 2014, June 2014, September 2014 and December 2014). The sampling points were chosen taking into account the possible pollution sources located in the study area. The samples were collected in polyethylene bags, using a clean stainless steel shovel and transported in laboratory. Using a portable multiparameter WTW INOLAB 320i for each sediment samples were determinated the physico-chemical parameters like pH, oxido-potential reduction, electrical conductivity and salinity. The heavy metals like manganese, iron, lead, cooper, cadmium, zinc, nickel and chromium were analzyed using an atomic absorption spectrometer ZEENIT 700. The heavy metals concentrations in analzyed sediment samples ranged between: 22.00 - 2575.00 mg/kg for Mn, 3372.00 - 57733.33 mg/kg for Fe, 29.52 - 8453.00 mg/kg for Zn, 5.30 - 318.00 mg/kg for Ni, 0.23 - 226.66 mg/kg for Cr, 11.46 - 12671.00 mg/kg for Pb, 0.10 - 63.66 mg/kg for Cd and 9.47 - 26824.27 mg/kg for Cu. The geoaccumulation index (Igeo) was calculated for almost every heavy metal determined (exception Fe) and a highly sediment contamination was found in the case of Pb followed by Zn, Cu, Cd, Mn, Ni and Cr. By calculating the Pollution Load lndex (PLI) and Sediment Pollution Index (SPI) it may be concluded that the most contaminated sediment sample was collected from a pipe which is directly discharged in Sasar River, without any previously treatment. [ABSTRACT FROM AUTHOR] more...

Waste landfilling has a considerable impact on the environment, due to the priority substances and priority hazardous substances that are released from the waste. Metals such as Pb, Ni, Cd, Zn and Hg and their compounds, are considered to be priority hazardous substances due to their persistence and bioaccumulation in ecosystems. Due to the presence of the hazardous substances in the electrical and electronic equipment, at the end of life, this equipment became hazardous waste and has a specific management way in the European Union. In the current concept of the sustainable development, the recovery represents a priority direction in the flow of waste management system. The purpose of this study is to propose for a composite material with CRT (cathode ray tubes) glass waste. The CRT glass waste is mechanically processed and is coming from WEEE. The used method for achieving the composite is an ecological recovery method, using hazardous waste from WEEE, with low energy consumption, reducing hereby the CO2 emissions that would be generated during conventional recovery processes thereof. Due to the ecological recovery method the composite material has a low cost. The experimental results, obtained after testing the compressive strength of the composite samples (55.98 N/mm ²), showed that the composite outperforms mortars in terms of mechanical strength. As a result, the obtained composite can be considered as construction material, framed in the mortars class, based on its aggregate size (particle size <4 mm) and on mechanical strength and can be successfully used for the production of decorative elements. [ABSTRACT FROM AUTHOR] more...