The effects of formation and functionalization of graphene-based membranes on their gas and water vapor permeation properties.

The gas and water vapor permeabilities of graphene-based membranes can be affected by the presence of different functional groups directly bound to the graphene network. In this work, one type of carboxylated graphene oxide (GO-COOH) and two types of graphene oxide synthesized i) under strong oxidative conditions directly from graphite (GO-1) and ii) under mild oxidative conditions from exfoliated graphene (GO-2) were used as precursors of self-standing membranes prepared with thicknesses in the range of 12-55 μm via slow-vacuum filtration preparation method. It was observed that the permeabilities for all tested gases decreased in order GO-2 > GO-1 > GO-COOH and depended on both the arrangement of graphene sheets and their functionalization.

Push-pull amino-nitro helicenes: synthesis, (chir)optical properties and self-assembly into thin films.

A series of regioisomeric push-pull amino-nitro [6]helicenes and a related [7]helicene derivative were prepared and their racemates resolved into enantiomers. Compared to the parent helicenes, they exhibit red-shifted UV-Vis spectra, pronounced dipole moments, altered chiroptical properties such as remarkable optical rotatory power, and can form nanocrystalline Langmuir-Blodgett films.

Room-temperature synthesis of nanoceria for degradation of organophosphate pesticides and its regeneration and reuse.

A simple low-temperature water-based and one-pot synthesis was developed for the preparation of nanocrystalline CeO that was used for degradation of the toxic organophosphate pesticide parathion methyl. By changing the reaction temperature in the range from 5 °C to 95 °C, several properties (, crystallinity, grain size and surface area) of nanoceria can be easily controlled. The catalytic decomposition of parathion methyl to its degradation product 4-nitrophenol was highly dependent on the CeO preparation temperature.

Removal of anthracycline cytostatics from aquatic environment: Comparison of nanocrystalline titanium dioxide and decontamination agents.

Anthracyclines are a class of pharmaceuticals used in cancer treatment have the potential to negatively impact the environment. To study the possibilities of anthracyclines (represented by pirarubicin and valrubicin) removal, chemical inactivation using NaOH (0.01 M) and NaClO (5%) as decontamination agents and adsorption to powdered nanocrystalline titanium dioxide (TiO2) were compared.