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Pt NPs covered with zwitterionic amidinates as ligands exhibit an exciting ligand effect in the hydrogenation of carbonyl groups when electron donor/acceptor groups are introduced in the N-substituents., Ligand control of metal nanoparticles (MNPs) is rapidly gaining importance as ligands can stabilize the MNPs and regulate their catalytic properties. Herein we report the first example of Pt NPs ligated by imidazolium-amidinate ligands that bind strongly through the amidinate anion to the platinum surface atoms. The binding was established by 15N NMR spectroscopy, a precedent for nitrogen ligands on MNPs, and XPS. Both monodentate and bidentate coordination modes were found. DFT showed a high bonding energy of up to –48 kcal mol–1 for bidentate bonding to two adjacent metal atoms, which decreased to –28 ± 4 kcal mol–1 for monodentate bonding in the absence of impediments by other ligands. While the surface is densely covered with ligands, both IR and 13C MAS NMR spectra proved the adsorption of CO on the surface and thus the availability of sites for catalysis. A particle size dependent Knight shift was observed in the 13C MAS NMR spectra for the atoms that coordinate to the surface, but for small particles, ∼1.2 nm, it almost vanished, as theory for MNPs predicts; this had not been experimentally verified before. The Pt NPs were found to be catalysts for the hydrogenation of ketones and a notable ligand effect was observed in the hydrogenation of electron-poor carbonyl groups. The catalytic activity is influenced by remote electron donor/acceptor groups introduced in the aryl-N-substituents of the amidinates; p-anisyl groups on the ligand gave catalysts several times faster the ligand containing p-chlorophenyl groups.

A new genus and species, Hispanobrya barrancoi Jordana and Baquero, gen. n., sp. n. is described. It was found in the Gador Mountain range (Almer a, Spain). This genus is similar to Capbrya Barra, 1999, from South Africa. The distinguishing characteristics of the new genus are the presence of a post-antennal organ (PAO), no clear tenent hair, a characteristic unguis, the presence of a reduced trochanteral organ, and flattened body setae. The distribution of the bothriotricha is similar to that of the genus Capbrya.

A report on the results of a research into some aspects of the collembolan fauna of the Greek Nature Reserve associated with Lake Kerkini, known as Wetland Kerkini, is presented. The nature reserve is large and includes a wide variety of habitats, many of which were not included in this preliminary survey. From the areas sampled we recorded 44 species, of which 39 were previously described, two (Folsomia potapovi Jordana & Baquero n. sp., Entomobrya naziridisi Jordana & Baquero n. sp.), are new to science, while three are identifi ed to generic level; a further 21 are new records for Greece, and an additional 11 species are new records to the Greek Mainland. Sampling with Berlese- Tullgren funnels and Malaise traps allowed us to capture species typical of soil and species present over vegetation. This summary is based on the records held in the online database of the Fauna Europaea Project.