Synthesis of the clathrate-I phase Ba(8-x)Si46 via redox reactions.

The clathrate-I phase Ba(8-x)Si(46) (space group Pm3̅n) was synthesized by oxidation of Ba(4)Li(2)Si(6) with gaseous HCl. Microcrystalline powders of the clathrate phase were obtained within a few minutes. The reaction temperature and the pressure of HCl were optimized to achieve good-quality crystalline products with a composition range of 1.

Silver Nanoparticles in SiO2 Microspheres - Preparation by Spray Drying and Use as Antimicrobial Agent.

Silver nanoparticles embedded in SiO2 particles of micrometer size are prepared using spray drying. The spray drying is performed with a SiO2 sol (solvent water:ethanol 4: 1) containing SiO2 and silver particles of nanometer size. During spray drying the SiO2 nanoparticles aggregate to SiO2 microspheres whereas the silver particles exhibit only a small tendency of aggregation and keep their nanometer size.

Ferroelectric electron holography.

Ferroelectrics are increasingly important as materials in semiconductor technology, e.g. for building non-volatile memory chips.