Treesearch

Who would think of cooking a potato in boiling rosin? The origin and rationale for this interesting cooking behavior is lost in ethno-botanical lore but directions for the practice persisted until recent editions of The Joy of Cooking (Rombauer and Becker 1975). Indeed, the dish can still be obtained at Sweetie Pies Restaurant (Decatur, TX) one day a week. We obtained rosin (Pinerez 1277), produced by Hexion Specialty Chemicals, to duplicate the cooking recipe and to investigate the gustatory effects. The basic recipe involves heating the rosin to 275 0F and carefully lowering the spud...

Trees can take up and assimilate contaminants from soil, subsurface, and groundwater. Contaminants in the transpiration stream can become bound or incorporated into the annual rings formed in trees of the temperate zones. The chemical analysis of precisely dated tree rings, called dendrochemistry, can be used to interpret past plant interactions with contaminants. This investigation demonstrates that dendrochemistry can be used to generate historical scenarios of past contamination of groundwater by chlorinated solvents at a site in Verl, Germany. Increment cores from trees at the Verl...

We planted a 5 acre cloverleaf in Prince George County, Virginia with native Virginia longleaf pine (Pinus palustris Mill.) in 1998. The seedlings were planted at low density (20+ foot centers) to mimic a savanna-style longleaf pine habitat. In 2009, mature cones were first observed in some trees within the planting site. This was an interesting observation in itself because open grown longleaf pines do not typically produce cones until 20 to 30 years (Wahlenberg 1946). Cone development for longleaf pine is unusual at 16 years (Wahlenberg 1946) and here cones had developed before 12 years...

Flexible electronics have a large number of potential applications including malleable displays and wearable computers. The current research into high-speed, flexible electronic substrates employs the use of plastics for the flexible substrate, but these plastics typically have drawbacks, such as high thermal expansion coefficients. Transparent films made from cellulose nanofibers have low thermal expansion and thus the potential to serve as substrates for flexible electronics. Here we present the results of using a cellulose nanofiber composite substrate for flexible electronics. While...

It is generally accepted that there should be an upward repetitive member allowable property adjustment. ASTM D245 (2011c) and ASTM D1990 (2011b) specify a 1.15 factor for allowable bending stress. This factor is also listed in ASTM D6555 (2011a, Table 1). In this technical note, sources of confusion regarding appropriate repetitive member factors are identified. This confusion casts some doubt on the validity of the 1.15 value.

Most wood species used in commercial and residential construction have little natural biological durability and will suffer from biodeterioration when exposed to moisture. Historically, this problem has been overcome by treating wood for outdoor use with toxic wood preservatives. As societal acceptance of chemical use changes, there is continual pressure to develop and market new types of durable wood products. In the last few years, several new types of wood preservatives have become available, and other new formulations are expected to appear on the near horizon. There is also increasing...

In this study, birch xylan was deposited onto elementally chlorine free (ECF) bleached eucalyptus kraft pulp, and the corresponding changes in physical properties were determined. An aqueous 5% birch xylan solution at pH 9 was added to 5 wt% slurry of bleached kraft eucalyptus fibers, with stirring at 70 C for 15 min after which the pH was adjusted to 5–6. The xylan enriched fibers were isolated by filtration and used for physical testing. A 1.15 wt% adsorption of birch xylan on the kraft fibers at 8% xylan addition increased the tensile index, strain and tensile energy absorption values...

Cellulose nanofibril/phenol formaldehyde (CNF/PF) composite films with high work of fracture were prepared by filtering a mixture of 2,2,6,6tetramethylpiperidine-1-oxyl (TEMPO) oxidized wood nanofibers and water-soluble phenol formaldehyde with resin contents ranging from 5 to 20 wt%, followed by hot pressing. The composites were characterized by tensile testing, dynamic mechanical analysis, scanning electron microscopy, atomic force microscopy, thermo-gravimetric analysis, and moisture/water absorption. Neat CNF films had tensile stress and Young's modulus of 232 MPa and 4.79 GPa,...

The role of biochar as a soil amendment on the adsorption¨C desorption and transport of tylosin, a macrolide class of veterinary antibiotic, is little known. In this study, batch and column experiments were conducted to investigate the adsorption kinetics and transport of tylosin in forest and agricultural corn field soils amended with hardwood and softwood biochars. Tylosin adsorption was rapid at initial stages, followed by slow and continued adsorption. Amounts of adsorption increased as the biochar amendment rate increased from 1 to 10%. For soils with the hardwood biochar, tylosin...

Structured biofoams have been prepared from the readily available renewable biopolymer xylan by employing an ice-templating technique, where the pore morphology of the material can be controlled by the solidification conditions and the molecular structure of the polysaccharide. Furthermore, reinforcement of these biodegradable foams using cellulose nanocrystals shows potential for strongly improved mechanical properties.