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This work aims to select adequate repair papers, based on fibre orientation information derived from paper objects during restoration, using non-destructive image analysis applied to micrographs of paper surfaces. Contemporary Japanese handmade papers exhibited high values of fibre orientation intensity, while contemporary Korean handmade papers exhibited low intensity values. This difference was assumed to be due to different sheet-forming actions. Model papers prepared in the laboratory by the still sheet-forming and flow sheet-forming methods had low and high values of fibre orientation intensity, respectively. Additionally the screen side for the flow sheet-forming method had a value of fibre orientation intensity higher than the top side. This fact was logically explained in terms of fibre flow and dehydration rate, and consequently suggests its applicability to distinguishing the sides of ancient document papers. The application of this technique to the Shimadzu Family documents from 1606 to 1859 indicated high values of fibre orientation, suggesting that the flow sheet-forming method had already been established by the early seventeenth century in Japan. The papers of Korean Buddhist sacred books manufactured between the eleventh and sixteenth centuries exhibited low orientation intensity values, and the differences between the two sides were small. This indicates that the papers were manufactured by the still sheet-forming method concurrently with a sideway swing. [ABSTRACT FROM AUTHOR]

The plastic waste problem has recently attracted unprecedented attention globally. To reduce the adverse eff ects on environments, biodegradable polymers have been studied to solve the problems. Poly(ε-caprolactone) (PCL) is one of the common biodegradable plastics used on its own or blended with natural polymers because of its excellent properties after blending. However, PCL and natural polymers are difficult to blend due to the polymers' properties. Grafted polymerization of maleic anhydride and dibenzoyl peroxide (DBPO) with PCL is one of the improvements used for blending immiscible polymers. In this study, we first focused on the effects of three factors (stirring time, maleic anhydride (MA) amount and benzoyl peroxide amount) on the grafting ratio with a maximum value of 4.16% when applying 3.000 g MA and 1.120 g DBPO to 3.375 g PCL with a stirring time of 18 h. After that, the grafting condition was studied based on the kinetic thermal decomposition and activation energy by the Coats-Redfern method. The optimal fitting model was confirmed by the determination coefficient of nearly 1 to explain the contracting volume mechanism of synthesized PCL-g-MA. Consequently, grafted MA hydrophilically augmented PCL as the reduced contact angle of water suggests, facilitating the creation of a plastic-biomaterial composite.

This study aims to develop an antibacterial agent that can be used for food packaging. Essential oils of Houttuynia cordata Thunb., a well-known medical herb, were extracted by two methods: multi-solvent consecutive extraction method and single ethanol extraction with a pre-heating method. Consequently, the extract obtained by the single ethanol extraction with a pre-heating method was more satisfactory from the operational and economic aspects. Afterwards, one of the encapsulation techniques: co-precipitation method using β-cyclodextrins as wall materials, was applied to form capsules for the protection of the obtained extract. After the capsule synthesis, the results of scanning electron micrographs and X-ray diffraction showed β-cyclodextrin crystallites in the form of thinner plates became oriented upon co-precipitation. Combining the results of Fourier transform-infrared spectra and an antibacterial assay using Bacillus subtilis as an object microorganism, the extract was confirmed to be successfully encapsulated within hollow cavities of β-cyclodextrins. A significant inhibitory activity on the growth and breeding of Bacillus subtilis was observed after the addition of fabricated capsules, which suggests the capsules containing the Houttuynia cordata Thunb. extract can be used as eco-friendly antibacterial agents for food packaging., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The two types of cellulose nanofiber (CNF) surface characteristics were evaluated by oil contact angle under ethanol-water solution at several concentrations as well as in air. Wood pulp-based 2,2,6,6-tetramethylpiperidine-1-oxylradical (TEMPO)-oxidized cellulose nanofiber (TOCNF) sheets and bamboo-derived mechanical counter collision cellulose nanofiber (ACC-CNF) sheets were fabricated by casting followed by drying. The CNF shows underwater superoleophobic mimicking fish skin properties and slippery surface mimicking Nepenthes pitcher. The underwater superoleophobic properties of CNF was evaluated theoretically and experimentally. The theoretical calculation and experimental results of contact angle showed a large deviation. The roughness, zeta potential, and water absorption at different concentrations were key factors that determine the deviation. Antifouling investigation revealed that CNF was a good candidate for antifouling material.

The saltwater immersion method was developed to inhibit mould growth on flood- or tsunami-damaged paper. Commercially available fine paper used for printing and writing showed decreased tensile indices after saltwater immersion. The salt remaining in the paper tended to increase the moisture content because of the salt deliquescence and moisture in the air. The tensile index was restored by removing salt from the paper. Crystallization and distribution of salt in interfibre pores were also considered to influence interfibre rebonding. The difference in the fibre responses to saltwater depended on the relationship between nano-scaled pores in the fibre walls, osmotic pressure, and the degree of sizing, which resulted in low water retention values. More of the starch applied as a surface sizing agent was dissolved or dispersed during distilled water immersion than saltwater immersion. This loosened the fibre network, which was a factor that decreased the sizing degree of the paper., (Copyright © 2014 Elsevier Ltd. All rights reserved.)