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As research advances, it is generally acknowledged that non -Saccharomyces yeast contribute to the addition of aromatic compounds during mead fermentation. In this experiment, eight different non- Saccharomyces strains and Saccharomyces cerevisiae co-fermentation, their aroma composition, and basic physicochemical parameters were investigated. More than 30 compounds with favourable impact were discovered using solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Co-fermentation of non- Saccharomyces spp. and S. cerevisiae can affect the concentration of volatile compounds, so that the mead presents different aroma characteristics. Co-fermented meads of Wickerhamomyces anomalus strains and S. cerevisiae (Wa 27-Sc and Wa 5-Sc) had higher alcohol, acids, aldehyde, and ester concentrations than those fermented with S. cerevisiae alone. In terms of taste, Wa 27-Sc was superior to Wa 5-Sc. Overall, the Wa 27-Sc received the highest score for its strong secondary aroma and good mouthfeel. The results show that the W. anomalus Wa 27 strain has a good potential to produce high quality mead. [ABSTRACT FROM AUTHOR]

The field electron emission is examined for amorphous carbon (a-C) films deposited on Si(100) substrates through a niobium carbide buffer layer at different flow rate ratios of C[H.sub.4]/(C[H.sub.4]+Ar) in a C[H.sub.4]/Ar mixture discharge. The results have shown that the work function of NbC is lower than that of Nb, showing that the high ratio of Nb-C/Nb-Nb bonds in the buffer layer has favored the field emission of a-C film.

The effect of a niobium carbide buffer layer with different structures in between amorphous carbon (a-C) film and Si substrate on the field electron emission for a-C films deposited by magnetron sputtering is examined. The first-principles calculated results have shown that the work function of cubic NbC is lower than that of hexagonal [Nb.sub.2]C, thus enhancing the electron emission of a-C.

Field electron emission is examined for amorphous carbon (a-C) films deposited on Si (100) substrates with a niobium buffer layer. The first-principles have shown that the formation of NbC has lowered the interface barrier and has improved the back contact between Nb and a-C films, thus increasing the field electron emission of a-C.

Abstract: Visible photoluminescence and its temperature dependence of La2/3Ca1/3MnO3 in the temperature range 138–293K were measured. It was observed that the main broad band centered at ∼1.77eV with the shoulders at ∼1.57 and ∼1.90eV existed in the entire temperature range. It can be well fitted by three Gaussian curves B1, B2 and B3 centered at ∼1.52, ∼1.75 and ∼1.92eV, respectively. The intensities of the peak B1 and B2 vary as temperature increases. In the entire temperature range, the intensity of B1 increases with increasing temperature, whereas that of B2 decreases. The photoluminescence mechanisms for La2/3Ca1/3MnO3 are presented based on the electronic structures formed by the interactions among spin, charge and lattice, in which B1 was identified with the charge transfer excitation of an electron from the lower Jahn–Teller split eg level of a Mn3+ ion to the eg level of an adjacent Mn4+ ion, B2 is assigned to the transition between the spin up and spin down eg bands separated by Hund''s coupling energy EJ and B3 is attributed to the transition, determined by the crystal field energy EC, between a t2g core electron of Mn3+ to the spin up eg bands of Mn4+ by a dipole allowed charge transfer process. [Copyright &y& Elsevier]

Diatomite which is a weak material in natural form possesses dielectric behavior and low reactivity. A new preparation method of thermally reduced graphene oxide/diatomite composites with a segregated network structure is exhibited. 13 wt.% glass powder is mixed in the diatomite. The diatomite particles coated graphene oxide in situ thermal reduction make electrical conductive composites; the percolation threshold is 0.229 vol.%. At the same time, the highest compressive strength of diatomite increased from 11.3 to 21.1 MPa. [ABSTRACT FROM AUTHOR]