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Temporary consolidation is a quite common practice during archeological excavations nowadays. Melts of cyclododecane or menthol are among the most used consolidants. When using melting protocol to consolidate fragile heritages in archaeological excavation sites, one of the most frequently encountered challenges is the poor penetration of the melt into the heritages, especially in cases of low environmental temperatures, high water content or compact substrates. In this work, we explore the possibility of using solvent-assisted menthol sols as temporary consolidant. Six common organic liquids are individually introduced into menthol at a concentration of 9.1 wt% to formulate room temperature menthol sols. Their potentials as temporary consolidants are systematically investigated. Experimental data indicate that solvent polarity is the most important feature for temporary consolidation purpose and ethanol with medium polarity is among the most appropriate solvents. Laboratory research results show that much better penetration behavior and good consolidation performances can be achieved in menthol-ethanol sol. The as-prepared menthol-ethanol sol is applied in Liangzhu archeological excavation site with satisfactory outcomes. This work shows that menthol-ethanol sol is an excellent temporary consolidation material for archaeological excavation purpose especially in extremely wet condition.

Tetraethoxysilane (TEOS) is the most commonly used silicon-based stone consolidant in art conservation. However, it is known that the resulting silica gel phase tends to develop cracks inside the stone as the gel shrinks during aging and drying. Such phenomenon may lead to severe damage to the protected objects. By introducing silica nanoparticles into TEOS, a so-called particle modified consolidant (PMC), may minimize such shrinkage by reducing the volume loss and forming mesoporous structure to weaken the capillary forces. But many previous results show significant color changes on the surface of PMC-treated stones which can not be tolerated in the conservation treatments of cultural heritage. In this work, we designed a three-component composite consolidant which consists of 15 nm silica particles, α,ω-hydroxyl-terminated polydimethylsilane (PDMS-OH) and TEOS. Among the three components, TEOS provides the consolidation function, silica nanoparticles prevent the cracking and increase the salt resistance and PDMS-OH further reduces cracking, decreases the color alteration and increases the resistance to wetting of the stone. Experimental results show that the three components have significant synergistic effect, which makes the material exhibiting best overall performance in terms of cultural heritage protection.

Tuning the enzyme-like activity and studying the interaction between biologically relevant species and nano-enzymes may facilitate the applications of nanostructures in mimicking natural enzymes. In this work, AuPt alloy nanoparticles (NPs) with varying compositions were prepared through a facile method by co-reduction of Au3+ and Pt2+ in aqueous solutions. The composition could be tuned easily by adjusting the molar ratios of added Pt2+ to Au3+. It was found that both peroxidase-like and oxidase-like activity of AuPt alloy NPs were highly dependent on the alloy compositions, which thus suggesting an effective way to tailor their catalytic properties. By investigating the inhibitory effects of HS− on the enzyme-like activity of AuPt alloy NPs and natural enzyme, we have developed a method for colorimetric detection of HS− and evaluation of the inhibiting effects of inhibitors on natural and artificial enzymes. In addition, the responsive ability of this method was influenced largely by the composition: AuPt alloy NPs show much lower limit of detection for HS− than Pt NPs while Pt NPs show wider linear range than AuPt alloy NPs. This study suggests the facile way not only for synthesis of alloy nanostructures, but also for tuning their catalytic activities and for use in bioanalysis.