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Strongly degraded cellulosic artworks usually need deacidification and consolidation. Alkaline nanoparticles are known to be effective in neutralizing the acidity, while cellulose nanocrystals have the potential to be used as compatible and effective strengthening agents. We have grafted cellulose nanocrystals with oleic acid using a 1′1-carbonyldiimidazole-mediated procedure, to increase their dispersibility in organic solvents, and synthesized Ca(OH) 2 or CaCO 3 nanoparticles via a solvothermal process. Grafted nanocellulose and alkaline nanoparticles were used to prepare ethanol-based "hybrids". Prior to the application, the physico-chemical properties of nanocellulose dispersions and "hybrids" were studied by rheology and small-angle X-ray scattering. Cellulose nanocrystals were effectively grafted and stably dispersed in ethanol. It was shown that the use of ethanol as a dispersing medium, and the addition of alkaline nanoparticles act in a synergistic way, increasing the interactions between grafted cellulose nanocrystals, leading to the formation of clusters. These dispersions are thixotropic, a behavior particularly appealing to conservation purposes, since they can be applied in the liquid state, or, when a more confined application is required, they can be applied in a gel-like state. As a result of the application, an improvement in the mechanical properties of paper and an increase of pH were obtained. [ABSTRACT FROM AUTHOR]

The use of a portable NMR device allows a non-invasive investigation of the paper in order to assess the state of conservation of books and documents of historical or artistic interest. The NMR investigation has been found mainly on relaxation measurements whose results seem compatible with different relaxation rates in crystalline and amorphous cellulose domains. By a simplified physical picture based on spin–diffusion it appears possible to detect the alteration of the crystalline/amorphous cellulose balance and therefore to get information on some deterioration processes of paper. The use of a portable NMR device shows great potentiality because of its safe and simple in situ approach to Cultural Heritage documents. In this work, we present a research carried out on a 17th century manuscript. [Copyright &y& Elsevier]

Paper–TiO 2 –Ag 2 O floating photocatalysts were produced under mild condition and their photocatalytic activity for the degradation of aromatic amine under sunlight stimulant was investigated. Characterizations by Raman, XRD, XPS, DRS and PL confirmed the presence of TiO 2 and Ag 2 O, and the morphology of the appended TiO 2 /Ag 2 O layer was probed by FE-SEM. The photocatalytic activity of the prepared samples was investigated by the degradation of aniline (AN) in water under simulated sun-light illumination and constrained conditions, i.e. non-stirring and non-oxygenation. The presence of Ag 2 O combined with TiO 2 was shown to improve the resistance of paper to bacteria attack, thus increasing the durability of the photocatalyst. Thanks to its hydrophobic character, the paper–TiO 2 –Ag 2 O NPs can be employed as useful floating photocatalyst and can be reused in continuous cycles. • Paper–TiO 2 decorated with Ag 2 O nanoparticles was prepared by a facile method. •Generation of TiO 2 anatase and Ag 2 O phases was confirmed by XRD, Raman and XPS. •Paper–TiO 2 –Ag 2 O exhibits excellent photodegradation activity toward of aniline. •Paper–TiO 2 –Ag 2 O displays good antibacterial activity against E. Coli under sunlight. [ABSTRACT FROM AUTHOR]