Uncovering selective and active Ga surface sites in gallia-alumina mixed-oxide propane dehydrogenation catalysts by dynamic nuclear polarization surface enhanced NMR spectroscopy.

Gallia-alumina (Ga,Al)O spinel-type solid solution nanoparticle catalysts for propane dehydrogenation (PDH) were prepared with four nominal Ga : Al atomic ratios (1 : 6, 1 : 3, 3 : 1, 1 : 0) using a colloidal synthesis approach. The structure, coordination environment and distribution of Ga and Al sites in these materials were investigated by X-ray diffraction, X-ray absorption spectroscopy (Ga K-edge) as well as Al and Ga solid state nuclear magnetic resonance. The surface acidity (Lewis or Brønsted) was probed using infrared spectroscopy with pyridine and 2,6-dimethylpyridine probe molecules, complemented by element-specific insights (Ga or Al) from dynamic nuclear polarization surface enhanced cross-polarization magic angle spinning N{Al} and N{Ga} coupling mediated heteronuclear multiple quantum correlation NMR experiments using N-labelled pyridine as a probe molecule.

-An Additional Parameter of Bathing Water Quality for Crowded Urban Beaches.

During the last years, the report of the occurrence of waterborne disease symptoms related to non-enteric pathogens has increased, without any record of higher levels of indicator bacteria ( and intestinal enterococci). Therefore, the use of current indicators is not always adequate when assessing the overall potential health risk and the inclusion of additional parameters needs to be examined. This paper reports on the incidence and levels of at 258 locations in Primorje-Gorski Kotar County (Croatia) recorded by official bathing water quality monitoring, as well as supplemental monitoring carried out at the two most frequented beaches in the City of Rijeka.

Boosting the Metathesis Activity of Molybdenum Oxo Alkylidenes by Tuning the Anionic Ligand σ Donation.

The catalytic performances of molecular and silica-supported molybdenum oxo alkylidene species bearing anionic O ligands [OR, OTPP, OHMT - where OR = OC(CF), OTPP = 2,3,5,6-tetraphenylphenoxy, OHMT = hexamethylterphenoxy] with different σ-donation abilities and sizes are evaluated in the metathesis of both internal and terminal olefins. Here, we show that the presence of the anionic nonafluoro--butoxy X ligand in Mo(O){═CH-4-(MeO)CH}(THF){X} (; X = OR) significantly increases the catalytic performances in the metathesis of both terminal and internal olefins. Its silica-supported equivalent displays slightly lower activity, albeit with improved stability.

Influence of Psychotic Episodes on Grey Matter Volume Changes in Patients with Schizophrenia.

Background: Schizophrenia is a severe illness whose clinical course is characterized by various numbers of psychotic episodes (PE). The neurotoxic hypothesis (NH) of schizophrenia assumes that psychosis is biologically toxic. The aim of the study was to investigate whether schizophrenia patients (SP) with multiple PE have greater grey matter volume (GMV) reduction compared to SP with fewer PE.