Sapwood and heartwood groundwood samples were prepared separately from a second growth, coastal range, young Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). The bleaching responses of these two groundwoods to zinc hydrosulfite were examined, and the roles of both dihydroquercetin and quercetin in this bleaching reaction were investigated. Heartwood groundwood was identified...
Automated size exclusion chromatography with a differential refractometer
detector was employed to study the molecular weight distribution patterns in various types
of wood pulp cellulose. The results obtained were correlated with the conventional
methods of measuring these properties.
The dissolution of pulp celluloses in N,N-dimethylacetamide-lithium chloride
solvent was optimized. This...
Because of the organic nature and the natural foaming characteristics
of kraft mill effluents, it was decided to investigate the
feasibility of using foam separation as a method of treatment. The
treatment efficiency was evaluated by BOD and COD reductions as
well as the decrease in toxicity to marine life....
While the heartwood of many wood species exhibits excellent resistance to fungal and insect attack, this resistance is sometimes diminished in second-growth material of the same species. The reasons for the reduced durability are unclear, but they may reflect a combination of both higher proportions of sapwood as well as...