The current study reflects the demand to mitigate the environmental issues caused by the waste from the agriculture and food industry. The crops that do not meet the supply chain requirements and waste from their processing are overfilling landfills. The mentioned wastes contain cellulose, which is the most abundant carbon precursor. Therefore, one of the possibilities of returning such waste into the life cycle could be preparing the activated carbon through an eco-friendly and simple route. Herein, the carrot pulp from the waste was used. Techniques such as thermogravimetric analysis (TGA), elemental analysis (EA), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and x-ray diffraction (XRD) were used to investigate the thermal treatment effect during the carbon material preparation. The development of microstructure, phase formation, and chemical composition of prepared material was evaluated. The obtained carbon material was finally tested for water cleaning from a synthetic pollutant such as rhodamine B and phloxine B. An adsorption mechanism was proposed on the base of positron annihilation lifetime spectroscopy (PALS) results and attributed to the responsible interactions. It was shown that a significant carbon sorbent from the organic waste for water purification was obtained.

Nanomaterials play an important role in metal matrix composites (MMC). In this study, 3.0 wt.%, 6.0 wt.%, and 9.0 wt.% nano-AlN-particles-reinforced AA6061 (nano-AlN/AA6061) composites were successfully prepared by pressure infiltration technique and then hot extruded (HE) at 500 °C. The microstructural characterization of the composites after HE show that the grain structure of the Al matrix is significantly refined, varying from 2 to 20 μm down to 1 to 3 μm. Nano-AlN particles in the composites are agglomerated around the matrix, and the distribution of nano-AlN is improved after HE. The interface between AA6061 and nano-AlN is clean and smooth, without interface reaction products. The 3.0 wt.% nano-AlN/AA6061 composite shows an uppermost yield and supreme tensile strength of 333 MPa and 445 MPa, respectively. The results show that the deformation procedure of the composite is beneficial to the further dispersion of nano-AlN particles and improves the strength of nano-AlN/AA6061 composite. At the same time, the strengthening mechanism active in the composites was discussed.

The creep properties of thermally stable ultrafine-grained Al metal matrix composite strengthened and stabilized by continuous in situ amorphous Al₂O₃ network (named HITEMAL^©) prepared by powder metallurgy (PM) were tested by small punch creep testing (SPCT) in the temperature range from 573 to 673 K. The experimental SPCT results were correlated and compared with the results obtained by conventional tensile creep testing. The mutual correlation between tensile and SPCT creep results based on the transition stress was proposed and used to correctly interpret the measured SPCT data. The creep behaviour of HITEMAL^© is characterized by the high values of apparent stress exponents and by the presence of transition stress at which the apparent stress exponents significantly changed. The SPCT discs fractured by the radial cracks at low values of deflection with only limited creep deformation highly localized in the vicinity of the fracture surfaces. The detailed analysis of fractured SPCT discs by scanning electron microscopy showed ductile dimpled fracture surfaces with the presence of unusual high filament-like tearing edges. The comparison of obtained results with other PM Al-based alloys and composites confirmed a significantly higher creep performance of HITEMAL^© at used testing conditions.

In this work Small Punch Test (SPT) was applied to study the mechanical behavior of ultrafine-grained Al-Al₂O₃metal matrix composites (MMCs) fabricated in situ via powder metallurgy route (HITEMAL®). Such MMCs show attractive mechanical properties, enhanced creep performance and increased thermal stability at elevated temperatures, not normally associated with service of conventional Al alloys, even after prolonged high temperature exposure. MMCs fabricated from two powders of different particle size (d50 = 8.9 and 1.2µm) were evaluated in the present work.