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The replacement of WC-Co cermet coating partially or entirely has evolved as one of the most promising research hotspots in terms of coating properties as well as economic reasons. In this study, the TiC reinforced AlCoCrFeNi high entropy alloy (HEA) composite coating based on new sintering method was explored. Firstly, the combination of spray drying and plasma spheroidization is proposed to fabricate TiC/HEA composite powder for thermal spraying application. After that, the corresponding composite coating was deposited by high velocity air-fuel (HVAF) process. The results show that the developed TiC/HEA powder has a more compact structure and higher sphericity, which helps to improve powder fluidity, meanwhile, with 50 wt% TiC incorporation, the porosity、hardness、bonding strength and fracture toughness of TiC/HEA composite coating are 0.8 % 765.2 HV0.3, 68.1 Mpa and 2.7 MPa m−1/2, respectively, showing simultaneous hardening, densifying and toughening effects after introducing dual-sized TiC particles. Besides, the good wear performances of TiC/HEA composite coating including low wear rate (4.2 × 10−5 mm3 N−1 m−1) and coefficient of friction (0.34) are obtained，indicating a valuable application prospect. In addition, the wear mechanisms of TiC/HEA composite coating are determined by abrasive and oxidation wears and that of grinding ball is abrasive wear and adhesive wears.

Transient voltage stability of power system with high penetration of renewable energy faces challenges. This paper proposes a method for quantitatively evaluating the impact of renewable energy penetration rate on transient voltage stability. Based on input-to-state stability (ISS) theory, security and stability indices are constructed to evaluate the stability characteristics, and a quantitative transient voltage stability assessment framework for power system with high penetration of renewable energy is established. Case studies are performed on MATLAB/Simulink, and security/stability indices under different renewable energy penetration rates are calculated. Finally, the critical scale of renewable energy integration is obtained through the coupling relationship between stability characteristics and renewable energy penetration rate.

Oxide dispersion strengthening (ODS) is an effective way to optimize mechanical performance, radiation tolerance and wear resistance in alloys. Therefore, in this research, lightweight and oxyphilic element Ti was utilized to induce oxides particles for in-situ fabricating ODS alloys. We investigated systematically the influence of Ti content on the phase evolution and mechanical behaviors of Ni1.5Co1.5CrTix (x = 0, 0.2, 0.4, molar ratio) multi-principal element alloys (MPEAs) fabricated by mechanically alloying and high-pressure sintering (HPS). The Ni1.5Co1.5CrTix powders presented BCC phase, FCC phase and few additional oxides. Following HPS, the BCC phase transformed to FCC phase in these MPEAs. Ni1.5Co1.5Cr MPEA was composed of FCC, Cr7C3 and Cr2O3 phases. As Ti content increased, Cr oxides or carbides gradually transformed into Ti oxides or carbides. The Ni1.5Co1.5CrTix (x = 0.2, 0.4) MPEAs after HPS displayed ultrafine grained FCC matrix and uniformly dispersed ultrafine/nano Cr-C or TiOC complex compounds. With Ti content increasing, the grain sizes of FCC matrix and precipitates had a tendency to decrease. Quantitative increment of precipitation-strengthening and fine-grain-strengthening clarifies the influence of Ti content on MPEAs. The investigations may provide key insights into tuning Ti content into the MPEAs for being available structural materials.

Pancreatic lipase (PL) inhibitor therapy is one of the most effective ways to treat obesity and obesity-associated metabolic disorders. Herein, bioactivity and liquid chromatograph-mass spectrometer (LC-MS) guided fractionation strategy was used to identify the naturally occurring PL inhibitors in Styrax, a popular folk medicine in Asia and Turkey. The results clearly showed that five pentacyclic triterpenoid acids in Styrax displayed strong inhibition on PL, with IC50 values ranging from 0.49 µM to 6.35 µM. Further investigations demonstrated that oleanonic acid and betulonic acid (the most two potent PL inhibitors in Styrax) potently inhibited PL in a reversible and mixed inhibition manner, while molecular dynamics simulations showed that these two agents could stably bind at the entrance to the active site of PL. Collectively, our findings revealed the molecular basis for the anti-obesity effects of Styrax, while the newly identified PL inhibitors in this herb could be used for development of novel anti-obesity agents.