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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]

The influence of temperature and relative humidity on the moisture content of paper honeycomb sandwich panels was studied, and the ideal three-dimensional diagram between the moisture content of paper honeycomb sandwich panels and the temperature and relative humidity was constructed by the GAB model. The evaluation equation of critical stress and plateau stress were obtained. The results indicate that the moisture content of paper honeycomb sandwich panels rises with the increase of relative humidity and declines with the increase of temperature; as the moisture content increases, the critical stress and plateau stress of paper honeycomb sandwich panels decline linearly; with the increase of the moisture content, the energy absorption of paper honeycomb sandwich panels increased firstly and then decreased; the evaluation equation of critical stress and plateau stress can predict the mechanical properties of paper honeycomb sandwich panels in different temperatures and relative humidities. [ABSTRACT FROM AUTHOR]

This article investigates an optimal design for a paper-feeding system that minimizes both jamming and simultaneous feeding of multiple papers, hereafter referred to as the multi-feeding rate. A total of 11 design parameters for the paper transfer device, the paper separation device, and the paper guide path are selected and analysed in this study. A test jig for feeding and transferring papers is manufactured to obtain experimental data for use in parameter analysis and design optimization. Back-propagation neural network-based causality analysis is employed to extract five dominant variables among 11 design parameters, and the results of causality analysis are compared with sensitivity results obtained from the analysis of means in the context of experimental design. Five-variable, second-order polynomial based approximate meta-models for jam rate and multi-feeding rate are then constructed, and numerical optimization is performed using NSGA-II, a non-dominated sorting genetic algorithm. Finally, two numerical Pareto optimal solutions are verified via experimental testing. [ABSTRACT FROM AUTHOR]

The effects of partial or complete replacement of two commercial fillers, carbon black (CB) and silica on cure characteristics, tensile properties, fatigue life, morphological properties, and rubber-filler interaction of paper sludge (PS) filled natural rubber composites were elucidated. Compounding was carried out on a two-roll mill with total filler loading of 30 phr. Results indicate that maximum torque, tensile strength, elongation at break, tensile modulus, and fatigue life increased the cure time while the scorch time decrease with increasing carbon black loading ratio of PS/CB filled natural rubber composites. On the other hand, increased loading of silica in PS/silica weight ratio resulted in an increment in cure time, scorch time, maximum torque, elongation at break, and fatigue life but not significantly altering tensile strength and tensile modulus of the natural rubber composites. In addition, PS/silica filled natural rubber composites exhibit lower maximum torque, tensile properties, and fatigue life compared to the PS/CB filled natural rubber composites. Rubber-filler interaction and SEM micrograph studies proved that the higher interaction between carbon black and natural rubber occurred in PS/CB filled natural rubber composites rather than PS/silica filled natural rubber composites. [ABSTRACT FROM AUTHOR]

Paper is a composite of fibers, air and additives where the fiber/fiber joints keep the network structure together. A study was undertaken to establish the link between the properties of the contact zone between fibers and paper performance under mechanical loading. The contact zone between fibers was investigated using light microscopy. A staining technique was developed for evaluating the influence of surface charge on fiber/fiber joint strength. The joint strength was linearly correlated with paper tensile strength and with the average amplitude of the acoustic events measured by acoustic emission testing. The fiber surface conformability was improved by changing the surface charge. This resulted in increased fiber/fiber joint strength as the relative contact area became larger. Increasing the molecular adhesion in the contact zone with the aid of strength additives also improved the fiber/fiber joint strength. [ABSTRACT FROM AUTHOR]

The effects of surface treatment of paper sludge (PS) with acrylic acid (esterification) and acetic acid (acetylation) on torque, stabilization torque, mechanical properties, water absorption, morphology, and thermal properties of PP/EPDM/PS composites were studied. It was found that esterified and acetylated composites exhibit higher stabilization torque than untreated composites. The esterification and acetylation treatment have improved the tensile strength, elongation at break, and Young's modulus but have reduced the water absorption of composites. The scanning electron microscopy (SEM) study of the tensile fracture surface of the esterified and acetylated composites indicates that the presence of acrylic acid and acetic acid increased the interfacial interaction between paper sludge and PP/EPDM matrix. The esterification and acetylation treatment also increase the thermal stability and crystallization of PP/EPDM/PS composites. It was found that paper sludge acts as a nucleation agent in the presence of acrylic acid and acetic acid. [ABSTRACT FROM AUTHOR]

The effect of paper sludge content and size on the processibility, mechanical properties, swelling behavior and morphology of PP--EPDM composites were examined. Results show that the increasing content of paper sludge in composites has increased the Young's modulus and water absorption but decreased the tensile strength and elongation at break. At a similar filler content, PP--EPDM composites with the smallest size show the highest mechanical properties but the lowest water absorption resistance. SEM tensile fracture surface of composites show that the smallest size of paper sludge has better filler--matrix interaction than the larger size of paper sludge. Thermogravimetric analysis showed that the increase of paper sludge content has increased the thermal stability of PP--EPDM composites particularly at temperatures above 500°C. [ABSTRACT FROM AUTHOR]

This paper presents and analyses a method for synthesizing the feedback block of a 2-d.o.f. real PID regulator, referring to the widely used ISA structure and particularly well suited for autotuning. A rigorous stability, performance, robustness and consistency analysis is provided, extending some results of the previous literature. An objective criterion is devised for selecting the method's (single) design parameter based on the process model employed and an overestimate of the corresponding process/model mismatch. Both simulation and practical application examples are reported. [ABSTRACT FROM AUTHOR]

Corn by-products can be used as bedding and nesting products. Corn-cob bedding resists ammonia build-up and corn-husk nesting material resists dampness. It is not clear whether these advantages are at the expense of animal comfort. Corn cob was compared to aspen chip bedding, and corn husk to paper strip nesting material. Data from 20 rats with differential early bedding experience suggested that they prefer aspen chip, but are also biased towards the bedding they were raised on. Data from 10 rats with no prior nesting material experience suggested that paper strip was preferred over cornhusk. Thus, corn-cob products are not recommended except in situations where air quality and/or flooding are significant problems. [ABSTRACT FROM AUTHOR]

The manipulation of the physical characteristics of nonwovens and paper by variation of fiber and web geometry is briefly reviewed in terms of a new system of bonding in which the adhesive interfiber forces are a consequence of ionic chemical bonds.These bonds were created by the sequential covalent introduction of anionic sites onto the interior and exterior surfaces of microporous pulp and rayon fibers using a chloro-s-triazinyl fiber reactive dye and subsequent stoichiometric reaction with crosslinking polycations derived from ethylenimine.The tensile properties of both the pulp and rayon fiber assemblages were significantly augmented as a result of the development of both ionic inter- and intra-fiber bonds. [ABSTRACT FROM PUBLISHER]

The biodegradability of several packaging films was determined; the degradation of the polymeric films, polypropylene and poly(vinyl chloride), was compared to a coated paper and several coated cellophanes. The films were buried in bacterially-active soil and the extent of bacterial degradation was determined by measuring the reduction in tensile strength as a function of burial time. The results show that the polymeric films do not degrade after five weeks of soil burial while the glassine and cellophanes do degrade. Surprisingly, the cellophane films decompose at a faster rate than the coated glassine sheet. [ABSTRACT FROM PUBLISHER]