A simple paper-based analytical device using UV resin screen-printing for the determination of ammonium in soil.

This study reports a convenient and low cost paper-based analytical device (PAD) for measuring ammonium in soil. This PAD has been developed using an inexpensive UV resin solution, as a new hydrophobic material, with a screen-printing method to create hydrophobic areas. The paper-based colorimetric device was developed using a modified Berthelot reaction in which salicylate and dichloroisocyanurate are used in order to produce a green compound of 2-2 dicarboxyindophenol in the presence of ammonium.

Synthesis and organogelating behaviour of amino acid-functionalised triphenylenes.

Four novel amino acid-functionalised triphenylenes have been prepared with glycine, l-alanine, l-phenylalanine and l-tryptophan ethyl ester side-chains. The glycine derivative is a good gelator of chloroform, the alanine derivative gels ethanol and toluene, and the phenylalanine derivative gels benzene and toluene. The tryptophan derivative does not gel any of the solvents tested, most probably due to its more bulky structure, but forms microspheres by evaporation-induced self-assembly.

Adsorption and diffusion of benzene in the nanoporous catalysts FAU, ZSM-5 and MCM-22: a molecular dynamics study.

Molecular dynamics (MD) simulations of benzene in siliceous zeolites (FAU, ZSM-5, and MCM-22) were performed at loadings of 1, 2, 4, 8, and 16 molecules per supercell. The potential energy functions for these simulations were constructed in a semi-empirical way from existing potentials and experimental energetic data. The MD simulations were employed to analyze the dynamic properties of the benzene-zeolite systems.