Modified Dye for Water-Fast Ink-Jet Printing

A quaternary ammonium compound containing amino acid residue was synthesized by Converting 3-chloro-2-hydroxy-propyalkyldimethylammonium chlorides into its epoxide derivatives, then attaching an amino acid to the epoxide derivatives synthesized a quaternary ammonium compound containing amino acid residue. Modified dyes were prepared by the ionotropy of anionic dyes with the quaternary ammonium compound containing amino acid residue. It was discovered that the modified dyes exhibited an excellent pH controllable solubility. These modified dyes have good water solubility at pH> 8.0, but they were water insoluble at pH < 6.5. On the printing paper, modified dyes in water-based ink-jet print ink could convert to water insoluble form and give prints excellent water fastness.     

Ab initio determination of solid-state nanostructure

Advances in materials science and molecular biology followed rapidly from the ability to characterize atomic structure using single crystals. Structure determination is more difficult if single crystals are not available. Many complex inorganic materials that are of interest in nanotechnology have no periodic long-range order and so their structures cannot be solved using crystallographic methods. Here we demonstrate that ab initio structure solution of these nanostructured materials is feasible using diffraction data in combination with distance geometry methods. Precise, sub-?ngstr?m resolution distance data are experimentally available from the atomic pair distribution function (PDF). Current PDF analysis consists of structure refinement from reasonable initial structure guesses and it is not clear, a priori, that sufficient information exists in the PDF to obtain a unique structural solution. Here we present and validate two algorithms for structure reconstruction from precise unassigned interatomic distances for a range of clusters. We then apply the algorithms to find a unique, ab initio, structural solution for C60 from PDF data alone. This opens the door to sub-?ngstr?m resolution structure solution of nanomaterials, even when crystallographic methods fail.