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More and more attention is being paid to the influence of powder mixing on the mechanical properties and corrosion resistance of WC-based cemented carbides. In this study, WC was mixed with Ni and Ni/Co, respectively, by chemical plating and co-precipitated-hydrogen reduction, which are labelled as WC-NiEP, WC-Ni/CoEP, WC-NiCP and WC-Ni/CoCP, respectively. After being densified in a vacuum, the density and grain size of CP were denser and finer than those of EP were. Simultaneously, the better mechanical properties of flexural strength (1110 MPa) and impact toughness (33 kJ/m2) were obtained by WC-Ni/CoCP due to the uniform distribution of WC and binding phase and solid solution enhancement of the Ni-Co alloy. In addition, the lowest self-corrosion current density of 8.17 × 10−7 A·cm−2, a self-corrosion potential of −0.25 V and the biggest corrosion resistance of 1.26 × 105 Ω in 3.5 wt % NaCl solution were obtained by WC-NiEP because of the presence of the Ni-Co-P alloy.

In this study, ultrafine WC@10Co powders were used for the fabrication of coarse-grained WC-10Co with almost full densification. The incorporation of WC@10Co resulted in a decreasing size of WC grain with a rounded shape, the mean free path of Co and the WC contiguity. Further, substantial Co with face-centered cubic structure dispersed uniformly in the cemented carbides with WC@10Co-contained intergranular fracture accompanied by a large number of plastic deformation tears of the Co phase at the fracture surface and crack bridges at the crack tip. Therefore, the hardness, fracture toughness and bending strength of cemented carbides with WC@10Co reached the highest levels of 1045.3 kgf m−2, 23.6 MPa·m1/2 and 2308 MPa, respectively. HIGHLIGHTS The ultrafine WC@10Co contracted size distribution of WC grain with a rounded shape. The uniformly dispersed Co with a high content of FCC structure was obtained. The as-obtained coarse-grained cemented carbides showed enhanced mechanical properties

It is of great significance for quality control to realize the discrimination for baijiu from different brands and origins. Strong-aroma-type baijiu (SAB), one of the most important Chinese aroma-type baijiu, exhibits the largest variety and market share. In this study, we proposed colorimetric sensor arrays based on gold nanoparticles (AuNPs) modified with different amino acids (AAs) to recognize the organic acids, and further distinguish different SABs. Three representative AAs, namely methionine (Met), tryptophan (Trp), and histidine (His), were selected to modify the AuNPs surface. The investigation of the effect of the main ingredients of SAB on AA@AuNPs aggregation confirmed that this aggregation mainly resulted from organic acids. Moreover, this aggregation was successfully used for differentiating 11 organic acids. Different pH conditions can not only cause changes of the content of organic acids in baijiu, but also disrupt the balance among flavor substances of baijiu to some extent. Consequently, the AA@AuNPs arrays under two pH conditions have been successfully applied to distinguish 14 kinds of SABs from different brands and origins. The proposed colorimetric sensor method is simple, rapid, and visualized and provides a potential application prospect for the quality control of baijiu and other alcoholic beverages.