Konjac glucomannan/sodium alginate composite edible boba (KGM/SA-boba) with good taste is very popular in China, and it is an outstanding carrier for health potential ingredients. In this work, KGM/ SA-boba were fortified with 0.25, 0.50, 0.75 and 1.00% purple sweet potato anthocyanin (PSPA), then characterised by the water distribution, texture, microstructure, in vitro release property of PSPA and antioxidant capacity. LF-NMR analysis demonstrated that the free water of KGM/SA-boba could transfer to tightly bound water with the addition of PSPA that made it with better water-binding ability, higher springiness and lower hardness. And the results of SEM and rheology showed that PSPA could stabilise the microstructure of KGM/SA-boba by forming more amorphous regions and hydrogen bonds proved by the results of DSC and FT-IR. Furthermore, 50% of PSPA in PSPA-fortified KGM/SA-boba can be released at the first hour in a simulated gastrointestinal environment. And the scavenging capacity of DPPH and ABTS of the PSPA-fortified KGM/SA-boba after digestion was higher than that of PSPA alone. Generally, PSPA could improve the texture while KGM/SA-boba in turn would make PSPA more stable in the gastrointestinal digestive system.

The hybrid Kevlar/PTFE (polytetrafluroethylene) fabric composites filled with different content nanoparticles of nano-Al 2 O 3 and expanded graphite, were respectively prepared by impregnating of Kevlar/PTFE fabric in phenolic resin containing nano-Al 2 O 3 and expanded graphite to be incorporated and the successive curing. To determine the tribological properties of these composites, the hybrid Kevlar/PTFE fabric composites filled with nano-Al 2 O 3 and expanded graphite dry-sliding against 45 steel were respectively performed on block-on-ring friction and wear tester. Scanning electron microscopy (SEM) was utilized to examine the morphologies of worn surfaces of the composites, to study modes of failure and the mechanism of the effects of the additives on the wear of the composites. The experiments results show that: the addition of nano-Al 2 O 3 at a proper content resin can improve the wear resistance of the composite, but increased the friction coefficient; the addition of expanded graphite can not improve the wear resistance obviously, and has no effect on the friction coefficient; the optimum mass fraction of nano-Al 2 O 3 and expanded graphite in the resin is respectively 1%; With the increase of the content of nano-Al 2 O 3 and expanded graphite in the matrix resin, the wear resistance of composites decrease dramatically, which may be due to the agglomeration of the additives in the matrix resin. The SEM observation on the worn surface morphology indicates that microcutting, plastic deformation and fibers-matrix debonding are the main wear mechanism of the fabric composites under dry-sliding.

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