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The British Library's Stein collection contains about 14,000 scrolls, fragments and booklets in Chinese from a cave in the Buddhist Mogao Caves complex near Dunhuang in north-west China. This article describes storage and access solutions for the collection in the context of a busy research library and the currently ongoing Lotus Sutra Manuscripts Digitisation project. The article presents the various technical and organisational challenges that its rehousing presents to the library conservators. Restricted by the existing storage facilities, budget limitations and tight project deadlines, the conservators must provide housing that is adequate for the scroll format, is practical and prevents dissociation, but is also cost- and time-effective. With the best storage practice in mind, they have developed original solutions, balancing the specific housing requirements and constraints. These storage solutions allow the conservators to ensure the long-term safety and accessibility of the collection while laying down a foundation of standardisation that will ensure a homogeneity of approaches for future projects. [ABSTRACT FROM AUTHOR]

This article reports on the design, fabrication, and characterization of an in-pipe worm-like soft robot with pneumatic actuators based on origami paper-fabric composites in which the paper and fabric serve as the skeleton and skin of the robot, respectively. The robot is assembled with an extensor of a bellow-like structure for implementing peristaltic locomotion and a clamp fabricated using a Kresling crease pattern at each end of the robot for anchoring. The performances of the pneumatic actuators, as well as the worm robot, are characterized and their dependence on some material, structural, and pneumatic parameters are investigated. Stepwise inflation of the clamp actuator takes place as the pressurization duration increases. The extension ratio of the extensor has a nonlinear relationship with the pressurization duration. The higher rigidity of the paper with a high weight per unit area can facilitate faster retention near the end of the extension process for the extensor with a small number of creases, while it becomes a resistance for the extension of the extensor with a large number of creases. The softness, lightweight features, low cost, ease to fabricate, modular design, and mobility of the worm robot indicate it has potential to find application in pipeline inspection, etc. [ABSTRACT FROM AUTHOR]

Authentication devices transform cheap paper into legitimate documents. They are the sensory, informational, and computational features that make up valuable papers like banknotes and passports, and they provide the confidence required in moments of exchange and passage. These devices – which include techniques like watermarks and specialized threads, proprietary substrates and inks, or RFID chips – are the product of security printing, an industry that continuously reinvents the possibilities of paper. Importantly, these components protect paper things from counterfeiting, allowing it to function as an original and authentic copy and to do the logistical work of connecting quotidian materials to global networks. The value of valuable papers is therefore not purely extrinsic, socially or discursively established, but is also performed through its intrinsic material qualities. These are the authentication devices that are read, assessed, and trusted as paper things are circulated, and they are what securely connects paper to infrastructures of mobility. [ABSTRACT FROM AUTHOR]

In this paper, a three-dimensional anisotropic multi-surface model for the in-plane elastoplastic deformation of paper and paperboard is developed. The model is based on the concept of structural tensors. It employs three different yield functions and parameterised consistency conditions for three different loading scenarios. The evolution of the yield surface with plastic strain is described by multiple hardening variables. Furthermore, the evolution equations are integrated using the unconditionally stable backward Euler method. Also, the internal variables are updated using a particular form of the elastic predictor/plastic corrector algorithm. The constitutive model is calibrated from a set of simple uniaxial tension tests performed in various directions of the material and is validated against loading in other directions. Additionally, the predictive capability as well as the numerical performance of the constitutive model is accessed against an existing non-quadratic plasticity model. Finally, the applicability of the constitutive model is demonstrated by performing a tensile test on a paperboard with a hole. [ABSTRACT FROM AUTHOR]

A kind of paper-based composite was prepared with short carbon fibers (CFs) and para-aramid fibrids through the process of papermaking. The dielectric properties of the paper-based composites at microwave frequency were investigated. Based on the Lichtenecker Rule, the dielectric constants of CFs in composites at different CF concentrations were calculated. The absorbing performances of paper-based composites were calculated from the test results of electromagnetic parameters. It was shown that for the composites loaded with 1 mm CFs, the real part of complex permittivity rises at first then tends to be stable with the increase of the CF content, and the imaginary part rises at first then falls slightly, while for composites loaded with 3 or 6 mm CFs, both the real and imaginary part of complex permittivity grows at first and then falls rapidly with the CF content increasing. When the CF content is below 10 wt%, the composites containing longer CFs have larger permittivity at the same concentration. The Lichtenecker Rule is found to be not suitable for the system studied in this paper, especially when the content of CFs is high. The variations of reflectance and absorbance with the content of CFs generally have analogous trends . It is also found that to achieve better absorbing performance, the length and content of CFs together with the thickness of composites should be considered. In this study, the lowest reflection loss at 10 GHz reaches –27.59 dB when the paper-based composite is loaded with 1 mm CFs at the concentration of 10 wt% and the optimum thickness of 1.84 mm. [ABSTRACT FROM AUTHOR]

A simple, facile and low-cost method for recycling of supercapacitor materials is proposed. This process aims to recover some fundamental components of a used supercapacitor, namely the electrolyte salt tetraethyl ammonium tetrafluoroborate (TEABF4) dissolved in an aprotic organic solvent such as acetonitrile (ACN), the carbonaceous material (activated charcoal, carbon nanotubes) purified, the current collector (aluminium foil) and the separator (paper) for further utilization. The method includes mechanical shredding of the supercapacitor in order to reduce its size, and separation of aluminium foil and paper from the carbonaceous resources containing TEABF4 by sieving. The extraction of TEABF4 from the carbonaceous material was based on its solubility in water and subsequent separation through filtering and distillation. A cyclic voltammetry curve of the recycled carbonaceous material revealed supercapacitor behaviour allowing a potential reutilization. Furthermore, as BF4− stemming from TEABF4 can be slowly hydrolysed in an aqueous environment, thus releasing F− anions, which are hazardous, we went on to their gradual trapping with calcium acetate and conversion to non-hazardous CaF2. [ABSTRACT FROM AUTHOR]