Treesearch

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...

Responsible stewardship of temperate forests can address key challenges posed by climate change through sequestering carbon, producing low-carbon products, and mitigating climate risks. Forest thinning and fuel reduction can mitigate climate-related risks like catastrophic wildfire. These treatments are often cost prohibitive, though, in part because of low demand for low-value wood “residues.” Where treatment occurs, this low-value wood is often burned or left to decay, releasing carbon. In this study, we demonstrate that innovative use of low-value wood, with improved potential revenues...

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...

The new photoload technique developed by RMRS provides a relatively inexpensive, fast, and accurate method to estimate loadings of major fuel components. This new technique allows land managers to create and use photoload sequences in any ecosystem worldwide for 1-hour, 10-hour, 100-hour, and 1,000-hour downed dead woody, shrub, and herbaceous fuels. The report provides a comprehensive protocol to create photoload sequences from field-sampled fuel beds, addresses common issues encountered in the field, and provides guidance for training field crews in the photoload sampling method.

RMRS scientists have developed an approach to estimating carbon stocks in rangelands. Above- and below-ground carbon storage in rangelands can be enhanced through vegetation management that includes deep-rooted perennial herbaceous plants, drought-tolerant herbaceous plants, and diverse native plants. Soil organic matter can be increased by increasing plant ground cover to protect soil and promote the formation of organic matter. Carbon stocks can be retained by limiting soil disturbance during management operations, limiting carbon losses due to catastrophic fires, and preventing conversio...

The pinyon jay has undergone an 80 percent decline in population in the last half-century, while the area of pinyon-juniper woodlands that they depend on has been expanding. Recent science has sought to tease apart specifically which portions of the pinyon-juniper forests are used by the jays to shed some light on possible reasons for the population declines.

A bark beetle outbreak killed 78 percent of overstory lodgepole pine on high-elevation study plots at the Fraser Experimental Forest in north-central Colorado. Of those snags, only 17 percent fell in the first decade after the peak of the outbreak.