https://bura.brunel.ac.uk/bitstream/2438/19228/3/FullText.pdf

The use of bacterial polysaccharides in bioprinting

Paper and paperboard are widely used in packaging products. The material behavior of paper and paperboard is very complex because different scales need to be considered in order to describe all relevant effects and phenomena. In particular, at least three scales can be distinguished: the fiber scale, network scale, and sheet scale. Since it is extremely challenging to measure the material behavior experimentally on all of these scales simultaneously, computational modeling of these materials has gained importance in recent years. This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions.

/pdf/a-review-of-recent-trends-and-challenges-in-computational-3f753bhwi2.pdf

A Review of Recent Trends and Challenges in Computational Modeling of Paper and Paperboard at Different Scales

Piezoelectric hydrogel nanocomposites are being developed as interface for connecting biological organs and electronics because of their flexibility, biocompatibility, and electromechanical behaviours, which allow environmental stimulations to be converted into electronic signals. The vision of this work is to develop a series of piezoelectric hydrogel nanocomposites which is capable of generating electric current in aqueous condition. Conductive nanoparticles have been composited in the PHEMA-based hydrogel. Theoretical models and characterisations on the electromechanical properties of such hydrogel have been investigated to assist the understanding of the piezoelectric mechanisms. The hydrogel nanocomposite was demonstrated as a self-powered motion sensor to quantitatively detect human motion and can be considered as candidate material for soft energy harvesting electronics. Overall, the work presented in this paper provides theoretical basis, design guidelines, and technical support for the development of soft self-powered electronics, thus unlocking the potential of piezoelectric hydrogel nanocomposites.

Understanding piezoelectric characteristics of PHEMA-based hydrogel nanocomposites as soft self-powered electronics

Dried-state bacterial cellulose (Acetobacter xylinum) and polyvinyl-alcohol-based hydrogel: An approach to a personal care material

Bacterial nanocellulose (BNC, as exopolysaccharide) synthesized by some specific bacteria strains is a fascinating biopolymer composed of the three-dimensional pure cellulosic nanofibrous matrix without containing lignin, hemicellulose, pectin, and other impurities as in plant-based cellulose. Due to its excellent biocompatibility (in vitro and in vivo), high water-holding capacity, flexibility, high mechanical properties, and a large number of hydroxyl groups that are most similar characteristics of native tissues, BNC has shown great potential in tissue engineering applications. This review focuses on and discusses the efficacy of BNC- or BNC-based biomaterials for hard tissue regeneration. In this review, we provide brief information on the key aspects of synthesis and properties of BNC, including solubility, biodegradability, thermal stability, antimicrobial ability, toxicity, and cellular response. Further, modification approaches are discussed briefly to improve the properties of BNC or BNC-based structures. In addition, various biomaterials by using BNC (as sacrificial template or matrix) or BNC in conjugation with polymers and/or fillers are reviewed and discussed for dental and bone tissue engineering applications. Moreover, the conclusion with perspective for future research directions of using BNC for hard tissue regeneration is briefly discussed.

https://www.mdpi.com/1996-1944/14/17/4777/pdf

Efficacy of Bacterial Nanocellulose in Hard Tissue Regeneration: A Review.

/pdf/assessing-stiffness-of-nanofibres-in-bacterial-cellulose-52xd3bkxxk.pdf

Assessing stiffness of nanofibres in bacterial cellulose hydrogels: Numerical-experimental framework

Deformation and Damage of Random Fibrous Networks

Mechanical modification of bacterial cellulose hydrogel under biaxial cyclic tension

Porosity of fibrous networks plays an important role in many processes, especially in filtration and separation applications. The paper aims to statistically analyze characteristics of porosity for...

Effect of microstructure on porosity of random fibrous networks

Fibrous networks are ubiquitous: they can be found in various engineering applications as well as in biological tissues. Due to complexity of their random microstructure, anisotropic properties and large deformation, their modelling is challenging. Though, there are numerous studies in literature focusing either on numerical simulations of fibrous networks or explaining their damage mechanisms at micro or meso-scale, the respective models usually do not include actual random microstructure and failure mechanisms. The microstructure of fibrous networks, together with highly non-linear mechanical behaviourof their fibres, is a key to initiation of damage, its spatial localization and ultimate failure [1]. Numerical models available in literature are not capable of elucidating actual microstructure of the material and, hence, its influence on damage processes in fibrous networks. To emulate a real-life microstructure in a developed finite-element model, an orientation distribution function for fibresobtained from X-ray micro computed-tomography images was considered to provide actual alignment of fibres. To validate the suggested model, notched and unnotched rectangular specimens were experimentally tested. A good correlation between the experimental data and simulation results was observed. This study revealed a significant effect of a notch on damage evolution.

https://iopscience.iop.org/article/10.1088/1742-6596/628/1/012093/pdf

Emrah Sozumert

Papers

Assessing stiffness of nanofibres in bacterial cellulose hydrogels: Numerical-experimental framework

Deformation and Damage of Random Fibrous Networks

Mechanical modification of bacterial cellulose hydrogel under biaxial cyclic tension

Effect of microstructure on porosity of random fibrous networks

Damage mechanisms of random fibrous networks