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[Display omitted] • Multi-layer forming technology can integrate triboelectric material with electrode. • The all CPTENGs can exhibit excellent humidity, acid and alkali resistance. • The CPTENGs can yield a V OC , I SC and power density of 227.1 V, 6.9 μA and 520 mW/m2. • Matching CPTENGs with P-ZISC can obtain a self-charging power system (PSCPS). • The PSCPS can drive some miniaturized electronics for a long time. Triboelectric nanogenerators (TENGs) are regarded as a promising technology to drive the development of flexible/wearable electronics and self-powering sensor. Application of cellulose paper as the triboelectric positive materials makes TENGs more environmentally friendly. However, the limited output performance and stability in harsh environments and oxidation and corrosion of the metal electrodes have limited the practical application of cellulose paper based triboelectric nanogenerators (CPTENGs). Here, we have integrated cellulose paper-based triboelectric material and electrode in one sheet by using multi-layer forming technology in paper industry; the upper triboelectric layer shows excellent triboelectric positive performance, hydrophobicity and acid and alkali resistance, while the bottom electrode exhibits promise conductivity. The all CPTENGs can yield a maximum open-circuit voltage (V OC) of 227.1 V, a short-circuit current (I SC) of 6.9 μA. Furthermore, the V OC values of the all CPTENGs increase from 0.02 V to 225.1 V at the load resistance of 100 Ω∼10 GΩ; and a power density of 520 mW·m−2 is also obtained at a load resistance of 30 MΩ. Moreover, the V OC of CPTENGs not only retains up to 78 % of its initial value at a high relative humidity of 90 %, but also almost maintains unchanged in a wide range of the pH environment (pH = 1∼13). More importantly, the CPTENGs can be readily matched with paper-based zinc supercapacitor (P-ZISC) to act as an all paper based self-charging power system (PSCPS). The PSCPS is capable of driving various miniaturized electronics, such as electronic watch, temperature/humidity indicator, demonstrating its potential application in a sustainable power source for portable and green electronics. [ABSTRACT FROM AUTHOR]

Predictive models for the transport of volatile organic compounds in paper need to consider the complex interplay of diffusion, adsorption, desorption, or chemical reactions. The relative importance of each of these processes is determined by the polarity of the volatile. Hence, it is challenging to pick a valid theoretical model that correctly predicts transport regardless of the polarity. Here, physics-informed neural networks (PINNs) assess which of five different models correctly describe transport of DMSO as polar and n-tetradecane as apolar model compound: (i) a pseudo first-order adsorption model for an irreversible sorption process, (ii) a first-order kinetics model allowing reversible sorption, (iii) a second-order model with a reversible process, and an effective diffusion model accounting for a constant (iv) and for a variable effective diffusivity (v). Each tested model is given as set of partial differential equations (PDE). Considering the model under testing and experimentally obtained spatially and temporally resolved concentration profiles through stacks of paper sheets, PINNs predict concentration of the volatiles and associated material constants such as sorption constants and effective diffusion coefficients by solving the inverse problem. Our PINNs revealed two models, pseudo first-order sorption and second-order reversible sorption, that correctly predict concentration profiles and polarity-driven differences in sorption times. While a PINN-based picking of valid transport models has important implications for the development of effective methods for controlling emission of volatiles from paper materials, PINNs represent a versatile mathematical tool to validate or refute the capability of PDE-based theoretical models to describe experimental data. • PINNs evaluate sorption kinetics in porous materials. • Focus: Transport of organic volatiles in cellulose. • Pseudo first-order model suits organic volatiles. • Predicting transport of volatiles through paper. [ABSTRACT FROM AUTHOR]

[Display omitted] • Honeycomb panels with discrete arranged block reinforcements were numerically designed. • The elastic moduli of the new honeycomb panels are higher than those of heavier panels with slatted. • Tables with new cellular panels are characterized by a stiffness of 85 % of the stiffness of heavier tables with slats. Furniture manufacturers indicate they know the benefits of lightweight honeycomb panels but still expect their higher mechanical properties. This work presents a numerical and experimental approach to designing new tables manufactured of paper honeycomb panels with discreetly arranged reinforcing blocks in the core. The main goal was to determine whether the discrete arrangement of the blocks affects the strength and amount of energy absorbed by the newly designed tables and stiffness of honeycomb panels. Optimization reduced the weight of the panels by up to 30 %. At the same time, their linear elastic modulus was increased from 1579 MPa to 1771 MPa. After ten load cycles, tables with discrete reinforcements have a stiffness up 86.85–87.20 % of the stiffness of the reference table. After destructive tests up 89.96–91.16 %. Ultimately, the test results demonstrate the effectiveness of replacing wide slats with discreetly placed reinforcing blocks in the core structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • For the first time the root cause for paper curl developing over days and weeks is described. • The curl of the paper sheets is caused by migration of co-solvents (e.g., glycerol) from the inkjet ink. • A 2D-laser scanner is utilized to investigate short- and long-term paper curl. • Glycerol migration in paper sheets is monitored using a combination of sheet splitting and subsequent HPLC analysis. The dimensional stability of paper during printing is crucial for ensuring production quality and runnability. However, inkjet printing faces inherent challenges due to the hygroscopic nature of paper and the use of water-based inks. Despite freshly printed sheets are flat, a considerable development of paper curl is often observed during storage. In this study, we establish the link between the migration of ink co-solvents and the long-term curl development of printed paper. A4 paper sheets were sprayed with a water-glycerol model ink and changes in the sheet's curvature were monitored using a 2D-laser sensor. We also investigated glycerol migration by splitting the sheets into layers and determining the glycerol distribution using high-performance liquid chromatography. Our results demonstrate the development of curl during storage as well as glycerol migration in thickness direction of the sheet, both on a comparable timescale. We thus propose that long term curl in inkjet printing can be caused by z-directional migration of the co-solvent (glycerol) over time. This study enhances understanding of the physical mechanisms that drive the long-term curl phenomenon in inkjet-printed sheets. The results can be used to optimize printing processes, allowing for the production of higher quality printed products with greater dimensional stability. [ABSTRACT FROM AUTHOR]