Treesearch

Lignin as a polyphenolic non-toxic bio-renewable polymer has been considered a promising candidate to replace phenol a relatively costly and toxic substance to reduce the carbon footprint and cost of phenolic resins. A detailed look at the current status of research in regard to ligninbased resins is presented. The discussion includes resins synthesized using lignin sourced from traditional pulping processes and the more recent biorefinery-based technologies, as well as the challenges facing lignin valorization

The multi-scale hierarchical structure of tooth enamel enables it to withstand a lifetime of damage without catastrophic failure. While many previous studies have investigated structure-function relationships in enamel, the effects of crystal misorientation on mechanical performance have not been assessed. To address this issue, in the present study, we review previously published polarization-dependent imaging contrast (PIC) maps of mouse and human enamel, and parrotfish enameloid, in which crystal orientations were measured and displayed in every 60-nm-pixel. By combining those previous...

Switchgrass was fractionated using maleic acid (MA) as an acid hydrotrope in comparison with p-toluenesulfonic acid (p-TsOH) at atmospheric pressure. MA achieved more rapid and greater maximal dissolution of lignin and hemicelluloses (88 % and 63 %, respectively) than did p-TsOH (73 % and 55 %, respectively). MA esterified (carboxylated) the dissolved acid hydrotropic lignin (AHL) as evidenced by 2D 1 H-13C HSQC NMR analysis, which improved AHL antioxidant ability compared with AHL from p-TsOH that is not carboxylated. MA also carboxylated the lignin and cellulose in the fractionated...

This work proposes the application of dicarboxylic acid cellulose nanofibril (DCA-CNF) obtained through maleic acid hydrolysis as an additive in water-based drilling fluids (WBMs). Specifically, the use of DCA-CNF as a replacement of xanthan gum (XGD) in the WBM formulations was evaluated. The effect of DCA-CNF on the main functional properties of WBMs and their performance was evaluated and compared with that corresponding to XGD. To this end, interactions between DCA-CNF and bentonite (BT), as well as between DCA-CNF and polyanionic cellulose (PAC), were studied using quartz crystal...

The meat industry in the US generates considerable amount of slaughterhouse waste (SHW), which is typically converted into more useable products through the rendering process. Although rendering generates sellable fat and meal commodities, it has large environmental impacts because it is energy intensive. Anaerobic digestion (AD) is a promising technology for treating SHW and reducing environmental impact through biogas production to generate heat or electricity, as well as by enabling nutrient recovery and pathogen reduction. This study compared the life-cycle energy use and global...

he Forest Products Laboratory (FPL), part of the USDA, in Madison, Wis., along with its new satellite laboratory in Starkville, Miss., have been involved in the examination and testing of wood preservative systems to improve durability of railroad ties and other wood products for the last 110 years. In keeping with the spirit of a pragmatic approach to research, FPL continues to devote a signifcant portion of its efforts toward applied research in wood preservation, often in collaboration with industry and university partners. In September of 2018, the FPL Starkville group partnered with...

Lignin is a multifunctional biopolymer with high application potential in the synthesis of thermoplastic materials. Industrial and investigational lignins have been incorporated into various commercial polymers, including biobased polymers, to improve their biodegradability, cost, and thermomechanical stability. Lignin is also expected to bring additional beneõts to the formulations, such as ôame retardancy, UV-protecting ability, and antioxidant and anti-weathering capacity. Strategies focused on lignin size reduction, fractionation, and modiõcation via esteriõcation, etheriõcation, and...

Cellulose is the most abundant biopolymer on Earth, found in trees, waste from agricultural crops and other biomass. The fibres that comprise cellulose can be broken down into building blocks, known as fibrillated cellulose, of varying, controllable dimensions that extend to the nanoscale. Fibrillated cellulose is harvested from renewable resources, so its sustainability potential combined with its other functional properties (mechanical, optical, thermal and fluidic, for example) gives this nanomaterial unique technological appeal. Here we explore the use of fibrillated cellulose in the...

The objective of this study is to examine the mechanical performance of cross laminated timber (CLT) panels made of low-value sugar maple under out of plane loads through mechanical tests and numerical simulation. The laminations were sorted into High and Low classes based on the measured modulus of elasticity (MOE). Two 3-layer sugar maple CLT layups as High-Low-High and Low-High-Low glued with resorcinol-based adhesive and one CLT layup of High-Low-High glued with melamine-based adhesive were prepared. Block shear, long-span bending (span-to-depth ratio of 33:1) and short-span bending...

This chapter introduces the Global Forest Products Model (GFPM). The general model structure and the mathematical formulation of the GFPM are provided and key differences and similarities to the modeling approaches developed in the previous chapters are highlighted. The usefulness of the GFPM as a forest sector tool for policy analysis is illustrated by summarizing its applications in a wide array of past and ongoing studies. These studies are summarized under four representative groups: (i) forest sector outlook studies; (ii) studies evaluating the consequences of tariff and non-tariff...