2-Propanol decomposition at 200 °C on magnesium oxide prepared by the hydrolysis of magnesium ethoxide (sol−gel method) is reported. With hydrochloride acid, acetic acid, or ammonia as hydrolysis alkoxide catalysts, the acidity and the selectivity to propene of the catalysts follow the sequence, MgO (HCl) > MgO (acetic acid) > MgO (ammonia). In contrast, the basicity of the samples, defined as the ratio dehydrogenation rate/dehydration rate, is found to be depending on the particle size of the catalysts. The basicity trend found is MgO (acetic acid) > MgO (ammonia) > MgO (HCl) and it correlates well with the particle size determined by the Rietveld refinement.

Microporous silica solids of SiO 2 and Ag/SiO 2 (a microporous SiO 2 substrate containing 5 wt % Ag) are synthesized by the sol-gel method and analyzed through several characterization techniques. The type I shapes of N 2 sorption isotherms at 76 K on these materials indicate large micropore contents as well as important cohesive interactions between adsorbed N 2 molecules, i.e., a gradual cooperative filling process becomes more and more evident as the concentration of adsorbate within the porous structure increases. In addition, negative values of the BET constant are found thus indicating that the adsorption mechanism on these solids can be better described in terms of a volume filling process rather than in terms of a multilayer formation phenomenon. The microporosity existing in these substrata is studied through Sing's R s -plots. The adsorption capacities of n-alkanes (i.e. n-hexane, n-heptane, n-octane, and n-nonane) on SiO 2 and Ag/SiO 2 substrata are measured by gas chromatography (GC) at different temperatures. The uptake of every hydrocarbon sorptive, on both SiO 2 and Ag/SiO 2 substrata, is found to be temperaturedependent. Additionally, the intensities of attractive interactions between hydrocarbon ad molecules and the surfaces of the above solids are evaluated for each adsorbate type from determinations of the isosteric heats of adsorption.

Volatile organic compounds (VOCs) produced by rhizobacteria have been proven to stimulate plant growth during germination and seedling stages. However, the modulating effect of bacterial volatiles on the germination of seeds subjected to heavy metal stress is scarcely studied. In this work, the ability of volatiles released by Bacillus sp. MH778713 to induce seed dormancy breakage in Prosopis laevigata and Arabidopsis thaliana seeds were examined. The minimal inhibitory concentration of chromium (Cr) VI that prevents seed germination of P. laevigata and A. thaliana on water-Cr-agar plates was 2500 and 100 mg L −1 , respectively. Remarkably, partitioned Petri-dish co-cultivation of Bacillus sp. MH778713 and plant seeds under Cr-stress showed the beneficial effect of volatiles emitted by Bacillus sp. MH778713, helping plant seeds to overcome Cr-stress. Among the metabolites emitted by Bacillus sp. MH778713, octadecane, heneicosane, 2,4-di-tert-butylphenol, hexadecane, eicosane, octacosane, and tetratriacontane were the most abundant. To confirm that these long-chain compounds produced by Bacillus sp. MH778713 could be responsible for the seed dormancy breakage, high pure organic compounds (2,4-di-tert-butylphenol, heneicosane, hentriacontane, and tetracosane) were used directly in germination assays of P. laevigata and A. thaliana seeds instead of volatiles emitted by Bacillus sp. MH778713. All organic compounds allowed Prosopis and Arabidopsis seeds to overcome Cr-toxicity and germinate. The results of this study provide new insight into the role of long-chain bacterial compounds produced by Bacillus sp. MH778713 as triggers of seed abiotic stress tolerance, surmounting chromium stress and stimulating seedling development.

Dealuminated mordenites depicting SiO 2 /Al 2 O 3 molar ratios in the range 10-206 were analyzed through adsorption methods. The Type I-IV hybrid shape of the N 2 adsorption isotherms at 76 K on dealuminated mordenites indicated rather high micropore contents, though some amount of mesopores of slit-like geometry was also present. Micropore volumes and sizes were measured through a S , t, and DA-plots, as well as by the NLDFT approach. Results indicated that mordenite dealumination caused micropore opening and widening as well as the emergence of further slit-like mesopores; even though a slight structural collapse toward creation of mesopore zones occurred at high dealumination extents.

The title chiral imine, C17H15NS, has been obtained via a direct synthesis route. The imine group displays the common E configuration, and is almost coplanar with the thio­phene heterocycle; the dihedral angle between the C=N—C group and the thio­phene ring is 5.1 (8)°. In contrast, the naphthyl group makes an angle of 83.79 (13)° with the thio­phene ring. The observed solid-state mol­ecular conformation is suitable for the use of this mol­ecule as an N,S-bidentate Schiff base ligand. The mol­ecular packing features double C—H⋯π inter­actions between naphthyl groups of neighboring mol­ecules, which form chains in the [100] direction. The crystal structure is further stabilized by a short C—H⋯π contact involving the methyl group and one ring of a naphthyl group. The resulting two-dimensional network is completed by a weak inter­molecular C—H(imine)⋯π(thio­phene) inter­action.