Bioactive glass (BG) nanoparticles have wide applications in bone repair due to their bone-bonding and biodegradable nature. In this work, nanometric rod-shaped ternary SiO2-CaO-P2O5 bioactive glass particles were prepared through sol-gel chemistry followed by a base-induced hydrothermal process at 130 °C and 170 °C for various times up to 36 h. This facile, low-temperature and surfactant-free hydrothermal process has shown to be capable of producing uniform nanorods and nanowires. One-dimensional growth of nanorods and the characteristics of siloxane bridging networks were dependent on the hydrothermal temperature and time. Hardened bioactive composites were prepared from BG nanorods and cryo-milled poly(vinylpyrrolidone-co-triethoxyvinylsilane) in the presence of ammonium phosphate as potential bone graft biomaterials. Covalent crosslinking has been observed between the organic and inorganic components within these composites. The ultimate compressive strength and modulus values increased with increasing co-polymer content, reaching 27 MPa and 500 MPa respectively with 30% co-polymer incorporation. The materials degraded in a controlled non-linear manner when incubated in phosphate-buffered saline from 6 h to 14 days. Fibroblast cell attachment and spreading on the composite were not as good as the positive control surfaces and suggested that they may require protein coating in order to promote favorable cell interactions.

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The problem of clogging membrane pores has become an area of interest for the vast majority of researchers in the field, because according to the literature, membrane materials are very sensitive when it comes to clogging and blocking pores. Therefore, this paper briefly describes the problems that occur during the process of obstruction the pores of the membrane. Models and characteristics of pore blocking mechanisms have also been developed. It is essential to mention that the principal purpose of the paper, which which consisted to review the simulations and classical models that were optimized, used in the analysis processes of clogging of membrane materials, was successfully fulfilled. According to those mentioned, the combined mathematical models of pore blocking (methods combined with three blocking mechanisms using Hagen-Poiseuille’s law or standard 0-order blocking) have proven to be very effective in describing membrane clogging problems.

At present, climate change is a global reality. One of its causes is the presence of pollutants in the atmosphere. Therefore, the purpose of this paper is to observe how the dispersion of pollutants is influenced by meteorological and topographic parameters. In order to carry out the study on the influence of synoptic conditions on the dispersion of air pollutants PM10 and CO, a continuous monitoring of the two pollutants was needed for one year (from March 2020 to February 2021) at all six air quality monitoring stations located in Argeș County. These data will be correlated with the climatological parameters obtained from the National Meteorological Administration. Using a numerical modeling program (SCREEN), it was performed a simulation of the dispersion of pollutants, determining the maximum concentration of the pollutant and the distance it reaches the ground, for several wind speeds, in all five classes of atmospheric stability.

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