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Abstract With the rapid development of flexible electronics, new opportunities are opening up for paper-based electrodes. Herein, an integrated paper electrode consisting of homogeneously mixed cellulose fibers, activated carbon (AC), and carbon black is fabricated using cotton stalks as the raw material. Assembled from two such electrodes, the flexible supercapacitor exhibits high energy density, high power density, and outstanding cyclability. Remarkably, the thickness and AC mass loading of the paper electrode can be easily scaled up to commercial levels (610 µm and 9.8 mg cm−2), while still delivering great performances. Moreover, it is demonstrated that the replacement of AC with Ni-Co layered double hydroxide or Fe 2 O 3 can result in paper-based asymmetric supercapacitor with extremely high energy density (331 μW h cm−2 and 10.3 mW h cm−3), substantially outperforming conventional paper-based supercapacitors. The fabrication methodology of integrated paper electrodes in this report manifests great potential, offering a new vision for flexible energy storage. Graphical abstract fx1 Highlights • An integrated paper electrode is fabricated using cotton stalks as the raw material. • The paper is composed of homogeneously mixed cellulose fibers, AC, and CB. • The paper thickness and AC mass loading can be easily scaled up to commercial levels. • The flexible symmetric supercapacitor delivers favorable energy and power densities. • The paper-based asymmetric supercapacitor exhibits extremely high energy density. [ABSTRACT FROM AUTHOR]

A large variety of acid-free Asian and Western papers offer objects conservators numerous applications in their work. Not only have objects conservators borrowed this extraordinary material - paper - from the field of paper conservation but they have also adopted many of the well-developed methods and techniques of handling and manipulating it in their 3-D treatments. Paper meets all material criteria in modern conservation practice, including reversibility, strength, inertness, long-term stability, minimal change in color over time, and compatibility with the original artwork. Additional attractive characteristics are that it is light weight, non-toxic, hydrophilic, it conforms well to surfaces, and is not affected by the solvents typically used. Also, the cost of paper varies but is not excessively high. Finally, having the option of using paper in sheet, fiber or powder form - either in a dry or wet state - allows for even wider applications. This article is a survey of the wide range of applications of paper in objects conservation. Its use can have two very different functions. It can serve as a restoration material, thereby remaining with the artwork after the treatment is complete, and as a tool during treatment, thereby not remaining with the artwork after the treatment is complete. [ABSTRACT FROM AUTHOR]

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This study focuses on the changes in properties of cellulose-based paper, which can take place as a consequence of its contamination by dust particles. The PM1 (fine) and PM10 (coarse) fractions of the dust particles from archival repositories were collected on cellulose filters Whatman 41, polytetrafluorethylene, and quartz filters. The latter two types of samples were subsequently analyzed gravimetrically, with ion chromatography, PIXE, and the thermal–optical transmission method, giving mass, ionic, elemental carbon, and organic carbon concentrations. After artificial aging, the viscosity-average degree of polymerization of cellulose (DPv) was measured. It was confirmed that cellulose-based paper can undergo substantial changes when contaminated by dust particles and artificially aged. The decrease of the DPvof cellulose showed a negative correlation with the deposited mass of sulfate ions in the dust particles. Considering the particle size fraction, the results suggest the decisive importance of the fine (PM1) particles. The results provide better understanding of how particulate matter contributes to the chemical degradation of cellulose-based paper. Such knowledge is of importance when considering appropriate conservation measures in archives, libraries, and galleries. [ABSTRACT FROM AUTHOR]

A systematic experimental study applying nanosecond laser pulses with 532 nm radiation to a specially selected set of historical paper samples exhibiting a broad range of composition and origin was undertaken to develop a quantitative irradiation dose model. This allows the optimisation of laser pulse number and fluence in order to maximise cleaning efficiency while excluding substrate modifications such as yellowing or destruction. [ABSTRACT FROM AUTHOR]

There has been a growing interest in laser cleaning applications for a variety of organic materials such as paper, parchment, textiles, and leather during the last decade. However, archaeological organic materials, notably papyrus, have rarely been investigated. This contribution examines whether removal of burial encrustation can be justified in view of its short-term and long-term effects on the substrate. To examine this, tests using mock objects have been performed. Using artificially soiled and archaeological papyrus samples, optimization of laser cleaning parameters using a picosecond laser (1064 nm, various operating conditions) was attempted. Optimization was based on colorimetry, optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and cellulose degree of polymerization data, both before and after accelerated degradation. In papyrus, there is no clear damage threshold, and substrate degradation can always be observed and is comparable in treated (cleaned) and untreated (soiled) objects. Therefore, the decision on whether to clean papyrus using lasers is predominantly based on aesthetic and treatability (e.g. need for consolidation) criteria. [ABSTRACT FROM AUTHOR]

Pressure screens are used to fractionate fibers on the basis of aspect ratio to obtain high value longfiber rejects and less desirable fines-rich accepts. Fiber fractionation is more practical and of maximum economic and commercial benefits when a mill can make use of all obtained fractions. We have demonstrated the potential of upgrading the reject fraction through a multistage fractionation process of a northern bleached softwood kraft pulp while isolating the remaining low-value pulp to be used as a raw material for a novel fiber-based product. The optimum operating conditions such as volumetric reject ratio, Rv; aperture velocity, Vs; and screen aperture size to carry out efficient fractionation were determined for the screens with 0.5-mm, 0.8-mm, and 1.0-mm apertures. This work shows that a high fines percentage in the accept fraction and increased fiber length in the reject fraction can be obtained when operating the pressure screen at a higher Rv and lower Vs using the screen cylinder with the small aperture size (0.5 mm). Feed and fractionated streams of pulp were used to study the effects on the physical properties of paper. Handsheets were made for strength properties of the unfractionated and fractionated pulps for comparisons. Significant improvements in the physical properties were observed after the removal of fines. [ABSTRACT FROM AUTHOR]

The current work analyses the potential usage of vegetal fibers environmentally sound based materials. The paper approaches the main applications of vegetal fiber sustainable integration into products. The origin of vegetal fibers and the degree of processing affect their chemical composition and furthermore its performance in future application. Some aspects on the structure and chemical composition of vegetal fibers are presented. The usage of vegetal fibers for manufacturing on paper and fiber containing composites is considered. Paper is the most important fiber based material and non woods as sustainable virgin fiber sources are discussed. Besides papermaking, vegetal fibers are potentially usable as reinforcements in cement and gypsum fiber composites. Some considerations regarding manufacturing processes and factors affecting mechanical properties of composites are presented. Other usages of vegetal fiber involve the manufacturing of polymer matrix composites. The chemical ways to improve interfacial linking between vegetal fibers and polymeric matrix are shortly underlined. Aspects regarding the environmental impact and life cycle assessment of the vegetal fiber based materials were taken into consideration. [ABSTRACT FROM AUTHOR]

Fabriano paper was aged by irradiation with ultraviolet light (λ=310) in a veterometer for 300 hours. At fixed time intervals, samples of the paper under test were analysed by titanium dioxide photosensor to determine electrochemically the ‘environmental persistence’ index, by a suitable conductimeter method, to determine the specific conductivity variation and by thermogravimetry to determine the moisture content, the onset temperature of the cellulose degradation process and the value of the activation energy of the same process. The behaviour of these different types of indicators displayed approximately monotonous trends as a function of time. [ABSTRACT FROM AUTHOR]

Chitosan can be used is precoating, before extrusion coating, to give better adhesion and improve barrier properties. A chitosan from natural polysaccharide was studied as a potential additive in paper coating. Four chitosan solutions were made with concentrations of 0.1%, 0.25%, 0.5%, and 0.75% by weight of total dry coating weight. Bending strength was improved significantly, but tear index and tensile index were improved only slightly. Water absorption was slightly reduced. This preliminary study indicates that chitosan has good adhesion onto cellulose and could be used as an environmentally friendly coating material. Future studies will concentrate on the aroma and oxygen barrier properties of chitosan. Application: Coating paper with chitosan, an abundant material, improves its bending stiffness and MD tensile strength. [ABSTRACT FROM AUTHOR]

Copyright of Fibres & Textiles in Eastern Europe is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)