Single dye molecules incorporated into a mesoporous matrix can act as highly sensitive reporters of their environment. Here, we use single TDI molecules incorporated as guests into hexagonal mesoporous films containing highly structured domains. The dye molecules allow us to map the size of these domains which can extend to over 100 microm. Investigation of the translational and orientational dynamics via single molecule fluorescence techniques gives structural as well as dynamical information about the host material. In an air atmosphere, the guest molecules show no movement but perfect orientation along the pore direction. The diffusion of the TDI molecules can be induced by placing the mesoporous film in a saturated atmosphere of chloroform. In single molecule measurements with very high positioning accuracy (down to 2-3 nm) the movement of molecules could be observed even between neighboring channels. This reveals the presence of defects like dead ends closing the pores or small openings in the silica walls between neighboring channels, where molecules can change from one channel to the next. A statistical analysis demonstrates that the diffusion of TDI in the mesoporous film cannot be described with a 1D-random diffusion but is more complicated due to the presence of adsorption sites in which the TDI molecules can be occasionally trapped.

The reactions of nanocrystalline tin metal (Sn*) with elemental selenium and tellurium and with the diaryldichalcogenides Ph2Se2 and Ph2Te2 have been investigated. Reaction of Sn* with the soluble tellurium source Ph2Te2 led to a clean formation of nanoparticles of cubic SnTe. Dependent on the concentration of Ph2Te2, the particles sizes could be varied between 15 and 60 nm in average, whereas the reaction of Sn* with Ph2Se2 formed molecular Sn(SePh)4 in high yield. The latter molecular compound was thermolyzed at 300 degrees C, yielding nanocrystalline SnSe with a broader distribution of size. The nanoparticles of SnTe were thoroughly investigated by transmission electron microscopy (TEM) and powder X-ray diffraction. The reactions of Sn* with elemental selenium and tellurium gave single- phase but microcrystalline SnSe and SnTe.

We identified three metal(II) salts of cyameluric acid, namely CaNH 4 (H 2 All three compounds were prepared by crystallization from aqueous ammonia solutions containing the respective metal(II) ions. Apparently, the copper salt is identical with a compound claimed in the literature with formula CuNH 4 C 6 N 7 O 3 · NH 3 . We studied the structure of all three compounds using single-crystal XRD (CaNH 4 (H 2 C 6 N 7 O 3 )(HC 6 N 7 O 3 ) · 6H 2 O:

In order to close the technology gap between membrane technologies and spray/freeze‐drying ideally with a technology that avoids thermal stress to sensitive enzyme solutions, the limits of freeze concentration for this application have been investigated. On laboratory scale it was found that average crystal sizes are > 300 µm despite high viscosity and ice separation is possible up to 42 % solids and > 1000 mm2s−1 viscosity. No activity loss was observed during concentration. A combination of two‐stage freeze concentration with a filter and wash column for ice liquid separation in an integrated setup with ultrafiltration has the greatest potential and was shown to be economically feasible in three out of four cases studied.