The hyaluronate molecule is a negatively charged polysaccharide that performs a plethora of physiological functions in many cell tissues depending on its conformation. In the present paper, molecular modeling at three levels of theory and two basis sets was used to gain a deeper insight in the complex molecular structure of calcium(II) and copper(II) hyaluronate. Simulation results were compared with the experimental data (EXAFS or X-ray). It was found that B3LYP does not properly reproduce the experimental data while the HF and M06 methods do. Simulation data confirm that the N-acetyl group of the N-acetylglucosamine residue does not participate in the coordination bonding to the calcium(II) or copper(II) ion, as evident from the experimental data.
COBISS.SI-ID: 36212485
Recirculation of leachate on a covered landfill site planted with willows or other highly evapotranspirative woody plants is an inexpensive option for leachate management. In our study, a closed landfill leachate recirculation system was established on a rehabilitated municipal solid waste landfill site with planted landfill cover. The main objective of the study was to evaluate the sustainability of the system with regard to high hydraulic loads of the landfill leachate on the landfill cover and high concentrations of saline ions, especially potassium (K+), sodium (Na+) and chloride (Cl−), in leachate. The results of intensive four years monitoring, including leachate, soil and plant samples, showed a high sustainability of the system regarding saline ions with the precipitation regime of the studied region.
COBISS.SI-ID: 33263365
Phytotoxicity and composition of two landfill leachates were studied. Phytotoxicity testing and physico-chemical parameters showed that the leachate generated in the active part of the landfill was significantly polluted and more toxic to plants than the leachate generated in the closed part of the landfill, which did not cause any significant adverse effects on root growth of plants tested in soil. However, the highest toxic effect of both leachates has been observed in the first days of plant germination. Phytotoxic pollutants have probably been degraded in the closed part of the landfill and leachates from such landfills are not significantly toxic to plants. Therefore phytoremediation appeared to be an appropriate restoration and treatment method.
COBISS.SI-ID: 35850757
On the basis of editorial invitation we published the article in the special issue of the leading journal for applied chemistry Advanced Synthesis & Catalysis dedicated to the environmentally friendly organofluorine chemistry. We showed that organic compounds could be selectively and efficiently fluorinated in water medium or under solvenfree reaction conditions (SFRC). A serie of 1,3diketones and beta keto esters were transformed to their alpha fluoro derivatives in water and under SFRC, while we first succeeded in the direct fluorination of ketones under SFRC. The present publication represents the greatest achievement of our laboratory in the last five years.
COBISS.SI-ID: 24083239