Depolymerising hemicellulose into platform sugar molecules is a key step in developing the concept of an integrated biorefinery. This reaction is traditionally catalysed by either enzymes or homogeneous mineral acids. We compared various solid catalysts for hemicellulose hydrolysis, running reactions in water, under neutral pH and relatively mild temperature and pressure (120 °C and 10 bar) conditions. Sulphonated resins are highly active, but they leach out sulphonic groups. Sulphonated silicas are less active, but more stable. They have weakly and strongly bound sites and the strongly bound ones do not leach. Zeolites are moderately active and stable. Among them, H-ferrierite especially, despite its small pores, exhibited high activity as well as good recyclability

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We investigated the influence of the reduction state of gold ions on the growth of gold nanocrystals in N,N-dimethyl formamide (DMF). While freshly prepared solutions of AuCl3 produce spherical nanocrystals, aged precursor solutions containing mainly Au+ ions and Au(0) atoms lead to various branched nanoparticles. Furthermore, we show that also the amount of the reducing and stabilisation agent tetra-n-octylammonium formate (TOAF) plays a decisive role on the shape of the nanocrystals, allowing us to grow triangular and cubic nanoparticles.

The connection between quantum size effects and the surface plasmon resonance of metal nanoclusters is introduced and the pros and cons of in situ and ex situ cluster analysis methods are outlined. A new method for estimating the size of nanoclusters is presented. This method combines core/shell cluster synthesis, UV-visible spectroscopy, and Mie theory. The core/shell approach enables the estimation of metal cluster sizes directly from the UV-visible spectra, even for transition metal nanoclusters such as Pd that have no distinct surface-plasmon peak in UV-visible region. Pd/Au and Au/Pd core/shell clusters as well as Au-Pd alloy clusters are synthesized and used as test cases for simulations and spectroscopic measurements. The results of the simulations and UV-visible spectroscopy experiments are validated with transmission electron microscopy.

Over two thousand years ago the Chinese developed a method to preserve eggs such that they remain edible for many months. The room temperature, physico-chemical preservation process that is used to prepare 'century' eggs transforms the egg white into a yellow, transparent gel with optical and mechanical properties that are very different to those of the familiar white protein aggregate that forms upon boiling a raw egg. Here we show that boiled egg white gels can be further transformed into an elastic and transparent gel using the Chinese preservation method. We demonstrate that the resulting protein gel is made of fine-stranded globular assemblies of partially denatured protein, and resembles the aggregates formed by colloidal particles interacting through long-range electrostatic repulsion combined with short-range attraction. These gels are not only highly deformable but are also very stable, maintaining their structure even when boiled. We suggest that the mechanism responsible for gelation in century eggs illustrates a non-specific aggregation pathway available to globular proteins.