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Scientists and statisticians working for the Rocky Mountain Research Station have created a software package that simplifies and automates many of the processes needed for converting models into maps. This software package, called ModelMap, has helped a variety of specialists and land managers to quickly convert data into easily understood graphical images. The software package also includes methods to test for accuracy. A true product of the information age, ModelMap combines many existing programming tool packages to streamline creation of sophisticated models from diverse data sources,...

Computational chemical methods have become an important technique in the examination of the structure and reactivity of lignin. The calculations can be based either on classical or quantum mechanics, with concomitant differences in computational intensity and size restrictions. The current paper will concentrate on results developed from the latter type of calculations for lignin model compounds. These methods can provide information on molecular geometry, thermodynamic properties, kinetics and electronic structure. Using density functional theory, the energies associated with bond...

Cinnamaldehyde amino acid Schiff base (CAAS) is a new class of safe, bioactive compounds which could be developed as potential antifungal agents for fungal infections. To design new cinnamaldehyde amino acid Schiff base compounds with high bioactivity, the quantitative structure–activity relationships (QSARs) for CAAS compounds against Aspergillus niger (A. niger) and Penicillium citrinum (P. citrinum) were analysed. The QSAR models (R2 =0.9346 for A. niger, R2 =0.9590 for P. citrinum,) were constructed and validated. The models indicated that the molecular polarity and the Max atomic...

Homogeneous modification of cellulose with succinic anhydride was performed using tetrabutylammonium acetate (TBAA)/dimethyl sulfoxide (DMSO) mixed solvent. The molar ratio of succinic anhydride (SA) to free hydroxyl groups in the anhydroglucose units (AGU), TBAA dosage, reaction temperature, and reaction time were investigated. The highest degree of substitution (DS) value of 1.191 was obtained in a 10 wt% TBAA/DMSO mixed solvent at 60 C for 60 min, and the molar ratio of SA/AGU was 6/1. The molar ratio of SA/AGU and the TBAA dosage showed a significant influence on the reaction. The...

This publication provides an overview of forest resources in Maryland based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. From 2004-2013, FIA employed an annual inventory measuring data on 20 percent of all sample plots each year in Maryland. Beginning in 2014, FIA is on a 7-year cycle, inventorying 14.3 percent of all plots annually. For the 2016 inventory, estimates for current variables such as area, volume, and biomass are based on 985 plots (432 forested) collected from 2011-2016. Change variables,...

Small wood specimens selected from six slash pine (Pinus elliottii) trees were inoculated with brown-rot and white-rot fungi and then evaluated for static modulus of elasticity (MOE) and dynamic MOE (MOEsw). The experimental variables studied included a brown-rot fungus (Gloeophyllum trabeum) and a white-rot fungus (Trametes versicolor) for six exposure periods (2, 4, 6, 8, 10, and 12 weeks). The MOEsw was tested by a stress wave timer prior to static bending and the results were compared via regression analyses. Regression analyses indicated good correlations between static MOE and MOEsw....

Fischer–Tropsch synthesis (FTS) with biomass- derived syngas was performed using both iron-based 100Fe/6Cu/4K/25Al catalyst and ruthenium-based 5 % Ru/SiO2 catalyst. During FTS, different concentrations of steam were co-fed with the biomass-derived syngas to promote the water gas shift reaction and increase the H2/ CO ratio. On Fe-based catalysts the increase in steam concentration led to lower conversion, while deactivation is not observed on Ru-based catalysts. XRD of the spent iron-based catalyst showed the oxidation of iron carbides. Adding steam inhibited surface carbon deposition, as...

Background: Lignin typically inhibits enzymatic hydrolysis of cellulosic biomass, but certain organosolv lignins or lignosulfonates enhance enzymatic hydrolysis. The hydrophobic and electrostatic interactions between lignin and cellulases play critical roles in the enzymatic hydrolysis process. However, how to incorporate these two interactions into the consideration of lignin effects has not been investigated. Results: We examined the physicochemical properties and the structures of ethanol organosolv lignins (EOL) from hardwood and softwood and ascertained the association between lignin...

Premise of research. Ferns are vital components of temperate and tropical ecosystems, but they have not been examined in the context of a central-peripheral hypothesis. Dryopteris fragrans is an ideal species to examine the genetic variation between central and peripheral populations because of its arctic north to temperate south distribution pattern. In addition to understanding colonization dynamics, our study also addresses the issue regarding the conservation value of peripheral plant populations. Methodology. We examined 82 individuals from 22 populations from northern Canada (N-CA)...

The renewable phenolic compounds produced by directional liquefaction of biomass are a mixture of complete fragments decomposed from native lignin. These compounds are unstable and difficult to use directly as biofuel. Here, we report an efficient in situ catalytic hydrogenation method that can convert phenolic compounds into saturated cyclohexanes. The process has high potential for production of hydrocarbon transportation fuels. In the in situ catalytic hydrogenation system, phenolic compounds were converted into cyclohexanol derivatives (that can be efficiently converted into cyclohexane...