No abstract

Ein Verfahren zur Wirkstoff‐Freisetzung auf ein externes Lasersignal hin, bei dem das An/Aus‐Verhältnis über 1000:1 beträgt, nutzt den Glasübergang hydrophober Polymere, bei dem sich das Diffusionsvermögen stark ändert. Die Bildung einer glasartigen Oberflächenschicht auf dem Implantat hat eine vernachlässigbare Freisetzung im Aus‐Zustand zur Folge. (Die Datenpunkte geben den Ibuprofenspiegel im Blut wieder).

In this article, we demonstrate the properties of a hydrogel capable of adsorbing calcium cations from aqueous streams at ambient temperatures (10-25 C) and showing almost complete desorption of the bound calcium ions at slightly elevated temperatures (40-50 C). Successful breakthrough experiments in a fixed bed column set-up show the potential of the hydrogel in softening water streams from 150 ppm toward <10 ppm hardness levels. The regeneration ability is based on the thermo-reversible internal ion pair-formation mechanism of the hydrogel. Additionally, it was shown that the thermo-reversible adsorption mechanism was successful for magnesium and copper ions too. The exploration of the properties of hydrogel CS-1B14 is the first step in the development of sustainable water-softening processes, both at industrial scale as well as for household applications, using low-grade residual heat to regenerate these gels. In this way, the use of concentrated brine streams, acid/caustic treatment, or high regeneration temperatures is avoided.