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In this study, a simplified two-dimensional axisymmetric finite element analysis (FEA) model was developed, using COMSOL Multiphysics® software, to simulate the water vapor separation in a moisture-selective hollow-fiber membrane for the application of air dehumidification in wood drying processes. The membrane material was dense polydimethylsiloxane (PDMS). A single hollow fiber membrane was modelled. The mass and momentum transfer equations were simultaneously solved to compute the water vapor concentration profile in the single hollow fiber membrane. A water vapor removal experiment was...

To improve the ability to recycle polyethylene (PE)-coated paperboard, one solution may be to use nanofibrillated cellulose (NFC) to generate a layer that should weaken when wet that leads to a clean separation between the polymer film and the pulp fibers. This NFC layer has the potential to improve the package's oxygen and grease barrier properties, but this system has not been explored in the literature. In this study, papers coated with zero, 2, and 4 g/m2 of NFC were laminated with a PE film under a range of pressing temperatures and times at a constant pressing pressure. A model was...

A fabrication process using acidic ethanol/water as a medium was developed to achieve homogenous dispersion of chitin nanofibrils (ChNFs) in a chitin propionate (CP) solution to form ChNF-reinforced CP nanocomposites. CP was prepared by propionylation of chitin to improve its dissolution in green organic solvents. ChNFs were extracted from chitin via partial alkali deacetylation in water. An acidified ethanol/water mixture as a medium was found to dissolve CP and disperse ChNF suspensions simultaneously, forming clear and stable formulations. The degree of ChNF dispersion and compatibility...

In fungi, adenosine-to-inosine (A-to-I) RNA-editing was shown to occur during sexual development and fruiting body formation in filamentous ascomycetes Fusarium graminearum, F. verticillioides, Neurospora crassa, Sordaria macrospora, and Pyronema confluens (Pezizomycotina) [1, 2], but absent during meiosis in the fission yeast Schizosaccharomyces pombe (Taphrinomycotina) [2]. In Basidiomycota, the first RNA-editing report was from Ganoderma lucidum, a mushroom-forming species of Polyporales, also during fruiting body formation [3]. Afterwards, Wu et al. reported RNA-editing events in...

Transparent gas barrier materials have extensive applications in packaging, pharmaceutical preservation, and electronics. Herein, we designed transparent films with a symmetric sandwich structure using layer-by-layer assembly of biaxially oriented polypropylene (BOPP) and acrylic resin (AR) followed by a cellulose nanoparticle (CNP) layer. The BOPP as a substrate created a barrier to hinder the transmission of water molecules to the adhesive AR layer and gas barrier functional CNP layer. The aspect ratio of the CNPs was shown to affect the film microstructure, resulting in different values...

Shou sugi ban, also known as yakisugi, or just sugi ban, is an aesthetic wood surface treatment that involves charring the surface of dimensional lumber, such as exterior cladding. The goal of this research is to examine the effect of shou sugi ban on the flammability and decay resistance of wood. Several species and variants of commercially available sugi ban were tested. The flammability was examined from the heat release rate curves using the oxygen consumption method and cone calorimeter. Durability was examined with a soil block assay for one white-rot fungus and one brown-rot fungus....

Buildings and the construction sector together account for about 39% of the global energy-related CO2 emissions. Recent building designs are introducing promising new mass timber products that have the capacity to partially replace concrete and steel in traditional buildings. The inherently lower environmental impacts of engineered wood products for construction are seen as one of the key strategies to mitigate climate change through their increased use in the construction sector. This chapter synthesizes the estimated carbon benefits of using engineered wood products and mass timber in...

The production of cellulose nanofibrils (CNFs) continues to receive considerable attention because of their desirable material characteristics for a variety of consumer applications. There are, however, challenges that remain in transitioning CNFs from research to widespread adoption in the industrial sectors, including production cost and material performance. This Review covers CNFs produced from nonconventional fibrillation methods as a potential alternative solution. Pretreating biomass by biological, chemical, mechanical, or physical means can render plant feedstocks more facile for...

In this work, TEMPO cellulose nanofibril (TOCNF) laminates were fabricated using a layup method. Two different TOCNF layers were tested, a neat TOCNF and a TOCNF with polyvinyl alcohol (PVA) strengthening aid with four different epoxy formulations as interlayers for the laminates. Flexural testing showed a correlation between the presence of stronger layers (TOCNFs + PVA) in the laminate with a higher flexural strength, bending modulus, and work of failure. Different modes of fracture within the laminates occurred based on epoxy type. A stiffer epoxy generated a reduced mechanical response...

In this study, cellulose nanofbrils (CNFs) were modified by catalyzed lactic acid esterification in an aqueous medium with SnCl2 as a catalyst. Films were made from unmodified and lactic acid-modified CNF without a polymer matrix to evaluate the effectiveness of the modification. Ungrafted and lactic acid-grafted CNF was also compounded with poly(lactic acid) (PLA) to produce composites. Mechanical, water absorption, and barrier properties were evaluated for ungrafted CNF, lactic acid-grafted CNF films, and PLA/CNF composites to ascertain the effect of lactic acid modification on the...