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A comprehensive study has been carried out to evaluate the extraction of heavy metals mixture (Co2+, Cr3+, Cu2+, Ni2+) from aqueous media by Winsor II non-ionic microemulsion, containing polyoxyethylene (4) lauryl ether as non-ionic surfactant and butyl acetate as organic phase. The extraction mechanism is based on the formation of thiocyanate complexes of metals and their transfer from aqueous to microemulsion phase, either towards the interfacial film of surfactant (Co2+) or into the core of micelles (Cr3+, Cu2+, Ni2+). The value of the distribution coefficient for Co2+ was higher than for the other studied metals and its extraction efficiency was not dependent on the working conditions, showing a maximum value (99.99%) in all cases. By using successive extractions, chromium, nickel and copper ions that remained in the aqueous phase after first extraction were transported into the microemulsion phase, leading to an increase in the extraction efficiency up to 99.99% for chromium and copper, and 85% for nickel. Based on pH influence, a selective extraction of Co2+ and Cr3+ can be achieved, since the cobalt ions were completely extracted into the microemulsion phase at pH = 1, and the chromium ions still remained in the aqueous phase. Keywords: Nonionic microemulsion, Thiocyanate complexes of heavy metals, Simultaneous heavy metals extraction, Microinterfacial effect, Synergism

The paper aims at testing an innovative organic fertilizer obtained from waste by processing a mixture of marine algae biomass, sewage municipal sludge and farmyard manure. Design of this polycomposite fertilizer is based on adequate conceptual and experimental models by taking into account the complex interactions among these three biomasses. In the first step a detail physico-chemical analysis has been performed on the composition of the three raw materials and also on the soil. In the second phase similar analyses have been carried out on representative samples of soil treated with the compost as compared with untreated soil samples. Analytical methods applied were FT-IR spectroscopy in correlation with organic/inorganic and total carbon (TOC/TIC/TC) analysis. The efficiency of applying this compost on the field at large scale has been assessed by means of fatty acid content of the oleaginous plants cultivated. Based on correlation between production quality and chemical composition of the composted soil, the optimal proportions of the mixture of the three organic wastes will be selected for designing an eco-friendly fertilizer able to improve agrochemical properties of the soil.

A class of fluorescent Au@SiO2 and SiO2@Au core–shell fluorescent nanoparticles has been synthesized using microemulsion assisted sol–gel method coupled with photoreduction reaction as an easy, rapid and versatile “one-pot” procedure. In the case of Au@SiO2-RhB (gold nanoparticles core coated with silica-Rhodamine B shell) different silica shell sizes were obtained ranging from 3 to 116 nm, while for RhB-SiO2@Au (Rhodamine B-silica core coated with gold nanoparticles shell) the size of gold shell falls within 3–38 nm interval. The synthesized core–shell nanoparticles have been characterized by a variety of techniques including Dynamic Light Scattering (DLS), High-Resolution Transmission Electron Microscopy (HR-TEM) coupled with Energy-Dispersive X-ray spectroscopy (EDX), Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD) and UV–VIS–NIR spectroscopy to confirm the size, shape, stability and topographic structure of the both core–shell nanostructures. The fluorescence enhancement of Rhodamine B (RhB) dye in the presence of gold nanoparticles (AuNPs) was demonstrated for the core–shell nanostructures synthesized in the present study, for different silica or gold shells. These interesting fluorescent core–shell nanoparticles provide ideal candidates for a variety of applications in materials science, biology, catalysis and optical fields.

The interactions of two ionic dyes, Crystal Violet and Methyl Orange, with different charged surfactants and also with a nonionic surfactant were investigated using surface tension measurements and visible spectroscopy in pre-micellar and post-micellar regions. It was found that for the water dominant phase systems the dye was localized between the polar heads, at the exterior of the direct micelle shells for all the systems. For the oil dominant phase systems, in case of the same charged dye/surfactant couples, the dye was localized in the micelle shell between the hydrocarbon chain of the surfactant nearby the hydrophilic head groups while for nonionic surfactant and oppositely charged dye/surfactant, localization of dye was between the oxyethylenic head groups towards the interior of the micelle core. Mixed aggregates of the dye and surfactant (below the critical micellar concentration of cationic surfactant), dye-surfactant ion pair and surfactant-micelles were present. The values of equilibrium constants (for TX-114/MO and TX-114/CV systems were 0.97 and 0.98, respectively), partition coefficients between the micellar and bulk water phases and standard free energy (for the nonionic systems were −12.59 kJ/mol for MO and −10.97 kJ/mol for CV) were calculated for all the studied systems. The partition processes were exothermic and occurred spontaneously.

This study aimed at exploring the behavior of fish oil enriched with ω-3 fatty acids in order to obtain stable lipid nanocarriers (NLCs) with improved characteristics as effective delivery systems for lutein. The particle size of optimized lutein-NLCs was below 200 nm. The less ordered arrangement of lipid core revealed by scanning calorimetry and the high entrapment efficiency of 88.5% clearly indicated the appropriate role of fish oil in obtaining effective lipid nanocarriers. The evaluation of in vitro antioxidant activity has demonstrated a significant blocking effect of NLCs, scavenging up to 98% oxygen free radicals. The in vitro release profile has shown that NLCs are able to ensure a better, in vitro sustained release of lutein as compared to conventional nanoemulsions.

Algae are a group of organisms, Thallophytes, containing specific bioactive compounds (i.e. brominated phenols, heterocyclic oxygen compounds, sterols, terpenes, polysaccharides). Their excessive growth has negative consequences on marine organisms; on the other hand, they have a crucial role in food, pharmaceuticals, cosmetics, agriculture. In this paper were studied the main physical-chemical characteristics correlated with the biological specificity of three species of multicellular algae, Enteromorpha intestinalis and Ulva rigida (green), Ceramium rubrum (red), frequently encountered along the Romanian Black Sea coast. Generally mixtures of thallophytes algae from the Black Sea were collected, processed and characterized. Density, pH, conductivity, anions, loss on drying, ash, total nitrogen, protein, lipids, carbohydrates, carotenoids were determined. The results emphasized the possibility of using these marine resources as biofertilizer in agriculture.

Due to their spectral characteristics, phototoxicity and high affinity for tumour tissues, porphyrins and their derivatives are widely used in modern medicine as contrast agents for cancer diagnostics and as sensitizers in photodynamic therapy, where they kill tumours via enhancement of tumour oxidative stress. The aim of this work was to simulate in vitro the effects caused by oxidation of two free base porphyrins, 5,10,15,20-tetraphenylporphyrin (TPP) and 5,10,15,20‑tetra(4‑methoxyphenyl)porphyrin (TMOPP). The kinetic study was monitored using spectral techniques and chemiluminescence. The effect of both porphyrins on an oxidation process was evidenced using the chemilumi-nescent system, luminal–hydrogen peroxide, in a phosphate buffer at pH 7. It was found that at low concentration, TPP exerts the anti-oxidative effect in the employed chemiluminescent system, while at higher concentrations; its effect is pro-oxidative. TMOPP exerts a pro-oxidant effect, which was more pronounced than TPP. The results are discussed with respect to oxidative stress.

New complexes of Cu(II) with some substituted 2-(3,5-dimethyl-pyrazol-1-yl)-methyl-acetanilides (L) hae been synthesized. The complex compounds, CuL4X2 (where X- = Cl,Br, CH3COO) were characterized by elemental analysis, as well as IR, UV-VIS, EPR spectroscopy. The study evidenced the influence of the position of the methyl group on the benzene ring and also of the anions on the physical properties of the compounds.