This study presents the results of an experimental investigation of wood combustion. Variables chosen for investigation were fuel feed rate, fuel moisture content, fuel particle size, excess air, fraction and temperature of under-fire air. Data recorded during the experiments included the composition and temperature of the combustion products in the combustion chamber, particulate emissions and combustible fraction of the particulate. Most mathematical models describing the combustion of wood particles require numerical solutions. For this investigation, an alternative model was used to generate closed form solutions for the determination of the burning times for wood particles in the combustion chamber. The model results were in good agreement with the experimental findings. The temperature profiles of combustion products within the combustion chamber were closely estimated, using an analytical model developed for this investigation. The composition profiles within the combustion chamber were estimated with the use of a chemical equilibrium model. These models were in good agreement with the experimental results for the estimation of the oxygen and carbon dioxide contents of the combustion products. The chemical equilibrium model proved to be inadequate for the determination of the NO[subscript x] and CO contents of the combustion products. Based upon the experimental data, a linear regression model was developed to investigate the variables affecting the combustion process. A computer model was used to calculate the temperature and composition of the combustion products under adiabatic conditions. Over the range of the variables considered, it was concluded that combustion efficiency and particulate emissions were most influenced by the factors that increased the volume and velocity of combustion products in the chamber. Moreover, it was also concluded that the part-load operation of the combustion unit resulted in higher particulate emissions and lower combustion efficiency. / Graduation date: 1991

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Wood formation (xylogenesis) is a critical developmental process for all woody land plants. As an initial step to understand the molecular basis for temporal and spatial regulation of xylogenesis and the effect of the expression of individual genes on physical and chemical properties of wood, microarray and realtime RTPCR analyses were performed to monitor gene expression during xylogenesis under various developmental and environmental conditions. The specific objectives established for this study were: Objective 1. Microarray analysis of genes preferentially expressed in differentiating xylem compared to other tissues of loblolly pine (see Chapter II); Objective 2. Microarray analysis of seasonal variation in gene expression for loblolly pines (Pinus taeda L.) from different geographical sources (see Chapter III); Objective 3. Realtime RTPCR analysis of loblolly pine AGP and AGPlike genes (see Chapter IV). Based on the results from this study, candidate genes may be further studied for association with significant traits, used for genetic modification of wood properties, or included in future studies to further examine the molecular mechanisms of wood formation.

Thesis (M.S.)--Oregon Graduate Center, 1979.

Thesis (Ph. D.) in Forest Resources--University of Maine, 2000. / Includes vita. Includes bibliographical references (leaves 135-141).

Thesis (Ph. D.) in Chemistry--University of Maine, 2003. / Includes vita. Includes bibliographical references (leaves 103-115).

Thesis (Ph. D.) in Chemical Engineering--University of Maine, 2003. / Includes vita. Includes bibliographical references (leaves 155-160).

Thesis (Ph. D.)--OGI School of Science & Engineering at OHSU, 2003. / Includes bibliographical references (leaves 129-151).