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Kolbach index (KI) is an important index to evaluate the qualities of malt, which will affect protein molecular composition, enzyme activity, and other macromolecules degradation during wheat malting. In this paper, the relationship between wheat (Triticum aestivum L.) malts KI and the (i) characterization of albumins, globulins, gliadins, and glutenins and their hydrolysis and (ii) the enzymatic breakdown of starch and arabinoxylans during malting were studied. As malt KI values increased, all fractions of glutenins and gliadins were extensively hydrolyzed. The higher Mw globulins (36.6 to 70.8 kDa) were also increasingly degraded at higher KI values, but the concentration of smaller globulin fractions (14.9 to 35.0 kDa) had increased significantly. As for albumins, although their overall concentration had increased as KI increased, changes in the concentration of individual albumin fractions was more complex. While there were significant increases in the concentration of some new albumin proteins (43.8 and 84.4 kDa), the concentration of some albumins decreased (21.1 to 64.3 kDa), and some fractions had completely disappeared (28.8 and 64.3 kDa). Following mashing, the hydrophobicity of the worts had decreased significantly at higher KI values. At malt KI values between 39.5% and 42.7%, the enzymatic activity was at its highest, the degradation of starch was adequate and stable, and the concentration of water-soluble arabinoxylans was optimal. A KI value of about 39.5% to 42.7% was therefore considered optimal for the production of wheat malts with superior quality attributes. PRACTICAL APPLICATION: The findings from this study will be valuable to beer companies; a more precise control of the malting and brewing parameters, fundamental for the production of high-quality wheat malts and wheat beer, can be achieved.

Catalytically active metals atomically dispersed on supports presents the ultimate atom utilization efficiency and cost‐effective pathway for electrocatalyst design. Optimizing the coordination nature of metal atoms represents the advanced strategy for enhancing the catalytic activity and the selectivity of single‐atom catalysts (SACs). Here, we designed a transition‐metal based sulfide‐Ni3S2 with abundant exposed Ni vacancies created by the interaction between chloride ions and the functional groups on the surface of Ni3S2 for the anchoring of atomically dispersed Pt (PtSA‐Ni3S2). The theoretical calculation reveals that unique Pt‐Ni3S2 support interaction increases the d orbital electron occupation at the Fermi level and leads to a shift‐down of the d ‐band center, which energetically enhances H2O adsorption and provides the optimum H binding sites. Introducing Pt into Ni position in Ni3S2 system can efficiently enhance electronic field distribution and construct a metallic‐state feature on the Pt sites by the orbital hybridization between S‐3p and Pt‐5d for improved reaction kinetics. Finally, the fabricated PtSA‐Ni3S2 SAC is supported by Ag nanowires network to construct a seamless conductive three‐dimensional (3D) nanostructure (PtSA‐Ni3S2@Ag NWs), and the developed catalyst shows an extremely great mass activity of 7.6 A mg−1 with 27‐time higher than the commercial Pt/C HER catalyst., A transition‐metal sulfide‐Ni3S2, with abundant exposed Ni vacancies in the outside layers, to anchor and modulate atomically dispersed Pt as the durable catalyst (PtSA‐Ni3S2) for efficiently electrocatalytic hydrogen evolution.

Tribocarbonisation of a fully formulated synthetic engine oil, an API SJ/SAE 5W-30 containing an organic molybdenum friction modifier, was investigated in an Optimal SRV® tribotester, with a Mo-coated piston ring and a cast iron cylinder bore tribopair in lubricated sliding contact and under stepwise heating conditions. The friction characteristics were determined by the friction coefficient curve which showed that two local minimum values occurred as the temperature increased stepwise. The local minimum friction coefficient at the lower temperature of 290°C was the result of the formation of MoS2 and MoO3, tribochemically generated by MoDTC and ZDTP. For the other local minimum friction coefficient at the higher temperature of 400°C, FT-IR and Raman spectroscopic examinations of the worn tracks on the cylinder bore samples indicated that tribopyrolysis of the oil components and simultaneous polycondensation into carbonaceous species had occurred. Detailed Raman analyses showed that the carbonaceous species included a disordered phase and an ordered phase characterised, respectively, by the D-line (1370 cm−1) and G-line (1580 cm−1). The peak positions and sizes of the graphite crystallites involved varied according to temperature, and were related to the specific points on the friction coefficient versus temperature curve. Tribochemistry could enhance pyrolysis of the oil and facilitate the production of the carbonaceous species and growth of the graphite crystallites.