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Nanocellulose contains a large number of hydroxyl groups that can be used to modify its surface due to its structure. Owing to its appealing features, such as high strength, great stiffness, and high surface area, nanocellulose is currently gaining popularity in research and industry. The extraction of nanocellulose from the leftover bagasse fiber from sugarcane production by alkaline and acid treatment was successful in this study, with a production yield of 55.6%. The FTIR and XPS results demonstrated a difference in the functional and chemical composition of untreated sugarcane bagasse and extracted nanocellulose. SEM imaging was used to examined the size of the nanocellulose with ImageJ software v1.8.0. TGA, DTG, and XRD analyses were also performed to demonstrate the successful extraction of nanocellulose in terms of its morphology, thermal stability, and crystal structure before and after extraction. The anti-S. aureus activity of the extracted nanocellulose was discovered by using an OD600 test and a colony counting method, and an inhibitory rate of 53.12% was achieved. According to the results, nanocellulose produced from residual sugarcane bagasse could be employed as an antibacterial agent. [ABSTRACT FROM AUTHOR]

Plastic waste is a global issue because it causes overflowing landfills and pollution, leading to environmental concerns. To address this crisis, materials that can be decomposed in the natural environment are introduced to replace conventional plastics. Poly‐ɛ‐caprolactone (PCL) is a commonly used plastic that can degrade in natural environments. However, owing to its hydrophobicity, its natural decomposition rate is low. In this study, PCL is modified with maleic anhydride (MA) (PCL‐g‐MA) to increase hydrophilicity and amorphous region for faster decomposition. To assess the hydrolysis in seawater, lipase hydrolysis is performed to compare the decomposition of PCL‐g‐MA and PCL. Consequently, in a Pseudomonas lipase‐containing PBS solution, it takes 72 and 120 h for complete hydrolyze of PCL‐g‐MA and PCL, respectively. MA grafted onto PCL increases the amorphous region, where lipase can easily diffuse into PCL‐g‐MA. Morphological (FESEM and POM images), thermal (TGA and DSC), and structural (FTIR, XRD, and XPS) analyzes support the hydrolysis reaction. The mechanisms proposed in this study confirm that lipase hydrolysis starts in the amorphous regions and then transfers to the crystal regions. This hydrolysis progress is expected to facilitate the creation of eco‐friendly low‐cost PCL‐g‐MA composites with high‐rate hydrolysis, such as bio‐plastics and bio‐fibers. [ABSTRACT FROM AUTHOR]

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This study aimed to prepare anti-Staphylococcus aureus inclusion complexes (ICs) of Hinoki essential oil (HEO) with β-cyclodextrin (β-CD) and 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD). An ultrasound-assisted kneading method was applied for the complexation for the first time. The recovery yield, embedding fraction and loading capacity of the HEO/β-CD ICs were 92.5%, 78.0% and 11.9%, respectively, while the corresponding values were 80.8%, 73.7% and 12.9% for the HEO/2-HP-β-CD ICs. As well, a comparative study confirmed the efficiency of the ultrasound-assisted kneading method was higher than the traditional kneading method. The results of SEM, XRD, GC-MS and FT-IR suggested the successful formation of ICs. A significant anti-Staphylococcus aureus activity of the fabricated ICs was demonstrated using a colony counting method. Notably, when the dose in liquid culture medium was 20 g L−1, inhibitory rates of 99.8% for HEO/β-CD ICs and 100% for HEO/2-HP-β-CD ICs were achieved. Furthermore, the hydrophilic property of the ICs was proved by water contact angle measurements, implying they have the potential to act as anti-Staphylococcus aureus agents for blending with hydrophilic biodegradable materials for diverse food packaging utilizations. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) generated from naturally aged Japanese hanging scrolls and their model samples were measured using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) to clarify the effect of different painting papers and raw materials on the degradation state of hanging scrolls. VOC-based degradation markers were identified and their applicability was considered for degradation evaluations of actual Japanese hanging scrolls. The relative peak areas of different VOC groups were calculated by normalising their peak areas to the total peak area of long-chain hydrocarbons. When a painting paper was immersed in a CuSO4・5H2O solution, or coated with an alum solution, the relative peak areas of furfural and carboxylic acids increased after accelerated ageing, while these relative peak areas decreased when animal glue was applied, indicating that animal glue inhibited the generation of VOCs. When the painting paper containing Cu2+ was stacked with lining paper, furfural and carboxylic acids migrated into the lining paper with ageing. Animal glue coated on the painting paper retarded this migration into the lining paper. For the lining paper coated with wheat starch paste, the relative peak areas of furfural, carboxylic acids, and aliphatic aldehydes did not change significantly with ageing, indicating that wheat starch paste did not contribute to paper degradation, although these relative peak areas increased when aged wheat starch paste was applied. These results indicate that the targeted VOCs are valid degradation markers of Japanese hanging scrolls. [ABSTRACT FROM AUTHOR]

To understand the degradation behaviour of rolled hanging scrolls for future conservation treatments, we evaluated the degradation–position profiles of naturally aged hanging scrolls and their model samples, which were subjected to different storage conditions. For the sample immersed in a CuSO4・5H2O solution and rolled around a glass rod, accelerated ageing using the open method (80°C, 65% RH) revealed a tendency of lower pH and higher discolouration towards the central positions, where rolling caused the most tightness. However, no clear tendencies were observed for the concentration variations of organic acids. The degradation effects of the organic acids emitted from the paulownia wooden box were also examined using the sealed tube method by enclosing the rolled painting paper and acidic paper containing organic acids together in a glass tube. Large amounts of oxalic and formic acids were detected at the periphery and scant migration of the organic acids was observed towards the centre, thus indicating that the central positions of the painting paper were less susceptible to the influence of the organic acids emitted from the external environment. By contrast, glycolic acid diffused towards the centre. The analysis of two naturally aged hanging scrolls showed different degradation behaviours. One sample, stored open in the rolled state, showed severe discolouration with the naked eye at the outermost back surface of the scroll. This was possibly associated with the large amount of sulfate ions originating from the external atmosphere, which kept the pH lower and increased discolouration towards the peripheral positions of the painting paper. For the sample stored in a paulownia wooden box, discolouration was not observed with the naked eye at the outermost back surface of the scroll, although lower pH and higher discolouration were observed towards the central positions. [ABSTRACT FROM AUTHOR]

One of the factors affecting the life expectancy of hanging scrolls is the storage environment. Our study focused on clarifying the degradation behaviour of painting paper, concentrating on the specific storage conditions that provide an airtight environment in a storage box and the stacked structure of the rolled paper rather than considering the materials of the wooden storage box or the gases generated from it. The degradation behaviour and rates for the sealed tube and moist heat ageing methods, excluding the additional effects of light and air pollutants, were compared. When the painting paper was immersed in a CuSO4・5H2O solution instead of a copper green pigment, the oxidation of the painting paper, attributed to Cu2+, proceeded faster with the sealed tube method than with the moist heat method. The co-occurring organic acids generated, namely glycolic and formic acids, which were secondary components, were detected in a higher amount in the first lining paper than the painting paper. This implies that the acids migrated from the painting paper into the lining paper. However, oxalic acid, which was the main component, did not significantly migrate and remained in the reaction system in the sealed tube without volatilising. This increased the hydrogen ion concentration in the painting paper and accelerated acid hydrolysis. Consequently, discolouration and a decrease in the degree of polymerisation and physical strength proceeded faster with the sealed tube method than with the moist heat method. Thus, although this result does not necessarily invalidate the storage system of a rolled hanging scroll in a box, the storage of a deteriorated hanging scroll in a closed system is expected to degrade the painting paper faster than it would in an open system. [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. [ABSTRACT FROM AUTHOR]

A Japanese painting paper is sized with an aqueous solution of alum and animal glue followed by brushing with a mixture of pigments of various colours and aqueous animal glue solution. Subsequently, to mount the Japanese painting to a hanging scroll, the backside of the painting is lined with a first lining paper using wheat starch paste for mechanical support. To evaluate the permanence of the painting paper as a composite material in the hanging scroll, the deterioration behaviour of the unlined painting paper and the lined painting paper was compared considering the material dynamics. After moist heat accelerated ageing (80°C, 65% RH), in the sample immersed in a CuSO4・5H2O solution, cellulose was oxidised by Cu2+ to generate organic acids in the painting paper, and Cu2+ and organic acids migrated to the lining paper. Consequently, the discolouration and oxidation of the painting paper in the lined complex were relatively low compared with those of the unlined painting paper. The pH decrease in the painting paper was also small in the lined complex. Moreover, if the animal glue solution was coated on the painting paper, a buffer effect was shown to operate against the organic acids derived from the oxidation of Cu2+, thereby inhibiting the migration of Cu2+ into the lining paper. In conclusion, the presence of the lining paper inhibited the decrease in the physical strength and degree of polymerisation of the cellulose in the painting paper, thus contributing to its permanence in the lined hanging scroll. [ABSTRACT FROM AUTHOR]

Acidification mechanisms of paper were examined, studying 120 pairs of identical copies of books published from 1971 to 2010 housed in two Japanese university libraries. The pH at the edges of the alkaline paper lowered from 7.5 to 6.4 after 5–10 years and to 5.8 after 10–15 years after publication. The pH bottomed at 5.4 at the edges and at 7.0 in the centre of the sheet. Acid paper showed higher pH at the edges than in the centre of the sheet. The edge pH of the alkaline paper of books stored on an above-ground floor was lower due to more exposure to incoming open air with pollutants compared to paper stored in the basement. Elemental analysis suggested nitrogen oxide deposition, but could not prove sulphur oxide deposition at the edges of the paper. The position-dependent acidification is presumed to relate to the deposition tendency of air pollutants contained in open air, and accordingly the edge pH dropped dramatically. In the 1980s, alkaline paper was increasingly used in the production of books, and it was assumed that no more book acidification was to occur; however, this study concludes that even in alkaline paper, acidification processes will take place over time. [ABSTRACT FROM AUTHOR]

Abstract: Vaterite-type calcium carbonate particles have some unique properties such as high hydrophilicity, large surface areas, and hierarchical structures consisting of primary vaterite particles in comparison with calcite- or aragonite-type polymorphs. In this paper, preparation conditions of vaterite by mixing treatment of two salt solutions, CaCl2 and K2CO3, were studied in terms of the presence of surfactant, agitation method of the solutions and other conditions. A double-cylinder-type homogenizer or ultrasonic homogenizer was used for agitation of the solutions. When suitable mixing conditions were adopted, pure vaterite was obtained as fine powders quantitatively by mixing the two salt solutions at room temperature without any surfactant using any types of homogenizers. When a polyoxyethylene sorbitan monofatty acid ester was present as a surfactant in the mixing solutions, pure vaterite but different morphologies or particle sizes were obtained, depending on the chemical structure of the surfactant used. The obtained results revealed that homogeneous, high-shear and constant agitation of the mixing solutions around 1 M salt concentration was necessary to prepare pure vaterite under the conditions used in this study. [Copyright &y& Elsevier]

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]

To expand the application field of the pulping industry, this study conducted a series of sample preparations for processing cellulose nanocrystals (CNCs) from a dry hardwood pulp to achieve optimal sulfuric acid hydrolysis. The properties of laboratory-prepared pulp CNCs (P-CNCs) were investigated with different preparation conditions including sulfuric acid concentrations, hydrolysis temperatures, and hydrolysis durations. Results showed a gradient of color changes observed with the increase of hydrolysis duration and temperature. Under certain conditions, the derived P-CNCs exhibited nanoscale dimensions, detected by transmission electron microscopy, and a crystallinity index similar to commercial products. In addition, the surface sulfate groups were assumed to be contributed by sulfuric acid hydrolysis. However, a high acid concentration and long hydrolysis processing duration introduced more sulfate groups on the derived P-CNCs, which may have acted as flame retardants and, thus, increased the amount of char residue. [ABSTRACT FROM AUTHOR]

A well-dispersed self-assembled silver nanoparticles (AgNPs) ink with high purity was synthesized via AgNO 3 emulsion prepared by blending an AgNO 3 aqueous solution and a liquid paraffin solution of both polyoxyethylene (20) sorbitan monooleate (Tween 80) and sorbitan monooleate (Span 80). The ink remained as an emulsion at low temperatures; however, it produced AgNPs after sintering at about 60°C and showed a high stability at nanoscale sizes (with diameters ranging 8.6-13.4 nm) and a high conductivity. During the whole procedure, Tween 80 acted as a surfactant, reductant and stabilizer. Presumably, Tween 80 underwent an autoxidation process, where a free radical of an α-carbon of ether oxygen was formed by hydrogen abstraction. The mean diameter of emulsion droplets could be reduced by decreasing water content and increasing the ratio of surfactant and concentration of AgNO 3 aqueous solution. Consequently, the thermogravimetric analysis and X-ray diffraction result clarified the purity of the produced Ag 0 . Dynamic light scattering and ultraviolet-visible spectroscopy clarified that an increased concentration of AgNO 3 decreased the particle size., Competing Interests: There are no conflicts to declare., (© 2020 The Authors.)

A non-destructive method for discriminating between different types of paper has been proposed, using image analysis, Fourier transformation, and cross-correlation matching. A fast Fourier transform (FFT) is used to extract the periodicity in the structure of paper that results from the manufacturing processes. The light-transmission images of the paper to be Fourier transformed are obtained from a flatbed image scanner. The similarity between the power spectrum of the FFT of the sample and that of a reference is quantified using a cross-correlation matching method. An advantage of using frequency analysis is that periodicity can be detected even if the sample is damaged or is printed on. The technique works on samples as small as 2 cm2.