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Medical and pharmaceutical research has shown that liposomes are very efficient in transporting drugs to targets. In this study, we prepared six liposome formulas, three in which we entrapped caffeic acid (CA), and three with only phospholipids and without CA. Determination of entrapment efficiency (EE) showed that regardless of the phospholipids used, the percentage of CA entrapment was up to 76%. The characterization of the liposomes was performed using Dynamic Light Scattering (DLS), Atomic Force Microscopy (AFM), zeta potential and polydispersity and showed that about 75–99% of the liposomes had dimensions between 40 ± 0.55–500 ± 1.45 nm. The size and zeta potential of liposomes were influenced by the type of phospholipid used to obtain them. CA release from liposomes was performed using a six-cell Franz diffusion system, and it was observed that the release of entrapped CA occurs gradually, the highest amount occurring in the first eight hours (over 80%), after which the release is much reduced. Additionally, the time stability of the obtained liposomes was analysed using univariate and multivariate statistical analysis. Therefore, liposomes offer great potential in CA entrapment.

Gold is one of the precious metals with multiple uses, whose deposits are much smaller than the global production needs. Therefore, extracting maximum gold quantities from industrial diluted solutions is a must. Am-L-GA is a new material, obtained by an Amberlite XAD7-type commercial resin, functionalized through saturation with L-glutamic acid, whose adsorption capacity has been proved to be higher than those of other materials utilized for gold adsorption. In this context, this article presents the results of a factorial design experiment for optimizing the gold recovery from residual solutions resulting from the electronics industry using Am-L-GA. Firstly, the material was characterized using atomic force microscopy (AFM), to emphasize the material’s characteristics, essential for the adsorption quality. Then, the study showed that among the parameters taken into account in the analysis (pH, temperature, initial gold concentration, and contact time), the initial gold concentration in the solution plays a determinant role in the removal process and the contact time has a slightly positive effect, whereas the pH and temperature do not influence the adsorption capacity. The maximum adsorption capacity of 29.27 mg/L was obtained by optimizing the adsorption process, with the control factors having the following values: contact time ~106 min, initial Au(III) concentration of ~164 mg/L, pH = 4, and temperature of 25 °C. It is highlighted that the factorial design method is an excellent instrument to determine the effects of different factors influencing the adsorption process. The method can be applied for any adsorption process if it is necessary to reduce the number of experiments, to diminish the resources or time consumption, or for expanding the investigation domain above the experimental limits.

Intriguing micro-currents in the graphenic oxide flakes obtained from the cracked fullerenes ozopolymers were predicted from their Raman spectra. They are interpreted with the aid of the bondonic theory combined with the inverse information for the quantum observed vs. quantum free evolution ratio, respectively. The peculiar quantum dots of the bondonic propagation in these nanoscopic systems may suggest the potentially critical phenomenology of phase transition, and possible local superconductivity by passing from the C60 derivative graphenic oxide to the C70 based compound. These results may have an impact on the future design of the graphene-based semiconductors, of the quantum graphenic gates, as well as on and the integrated graphenic microcircuits in the generic new field of graphentronics.

Ni11□(HPO3)8(OH)6 nanorods were the focus of three different studies. First, the thermal behaviour of the material was investigated and it outlined a good thermal stability up to 400 °C. Second, a comparative electrochemical study concerning the OER performance in alkaline medium of several graphite electrodes modified with the nickel phosphite was performed. The most promising electrodes were further characterised electrochemically and the electrode modified with Nafion solution and 5 mg Ni11□(HPO3)8(OH)6 exhibited the smallest overpotential value at the 10 mA cm−2 anodic current density (0.59 V), as well as the smallest Tafel slope (0.081 V dec−1). Furthermore, the constant potential electrolysis test revealed that this electrode is fairly stable within a time span of 300 min. Third, the capacity of Ni11□ (HPO3)8(OH)6 nanorods to remove MB and RhB were investigated under simulated visible light irradiation and positive results were obtained for the application as visible-light active photocatalyst. All this together corroborated with the eco-friendly nature of the materials, reinforces the fact that the phosphite type compound is a promising candidate for the design of new multifunctional and advanced materials.

The aim of this study is the enhancement of the electrical properties of thin films obtained from silver nanowires (AgNWs) deposited on a flexible polyethylene terephthalate (PET) support. First, AgNWs were obtained by the “polyol” liquid phase synthesis method in the presence of chloride ions. After purification, the AgNWs were successively deposited on a flexible support of PET by doctor blade method. To improve the adhesion of the AgNWs coating to the substrate, thin films of polymethyl methacrylate (PMMA) were interposed between the layer of AgNWs and PET substrate. The properties of the thin films have been studied depending on the number of AgNWs layers and heat treatment procedure. Characterization of pure AgNWs as well as of AgNWs/PMMA/PET structures has been carried out by x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray analysis, transmission electron microscopy, UV–Vis spectroscopy, and scanning probe microscopy. The sheet resistance of the transparent conducting...