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Average specific gravity of Emory oak (Quercus emoryi) estimated from 115 increment cores was 0.567 ± 0.011 (95 percent confidence interval). Increment core specific gravity is a predictor of average tree specific gravity. Diameter breast height (dbh) and diameter root collar (drc) were correlated with increment core specific gravity, but the correlations were too low to be valuable for predictive purposes. Estimated physical properties of Emory oak wood were lower than those reported for Gambel oak (Quercus gambelii) but higher than those reported for alligator juniper (Juniperus deppeana).

The design and implementation of a computer-assisted tree-ring chronology composition system for dendrochronology is described in this thesis. Methods for tree-ring growth sequence pattern matching, hierarchical composition of master chronologies, and analytical quality control are discussed in detail and systematically implemented in the CROSSDATE program in a highly visual, graphic environment. The objective of this work is to provide dendrochronologists with a robust set of tools for comparing the relative growth patterns of tree-ring samples for purposes of dating the samples and composing new master chronologies from individual tree-ring samples and other master chronologies. This system is complementary to the TREES program, a computer-vision based tree-ring identification and measurement system developed at the University of Arizona.

Mineral pigments are added to paper with the aim of improving its optical and printing properties. The colloidal behavior of calcium carbonate filler shows a dependence on the quality of water used in suspensions, presence of dissolved and colloidal substances and type of polymer used as a retention aid. The role of the retention aids is to attach colloidal particles, such as fines and mineral pigments, to pulp fibers before or during the paper is made. Two very different single-component retention aids were utilized in calcium carbonate fillers destabilization and deposition on fibers. Cationic polyethylenimine destabilized or facilitated deposition of the filler on fibers by a charge neutralization mechanism while cationic polyacrylamide flocculated or deposited the filler on fibers via a bridging mechanism. / In the presence of anionic dissolved and colloidal substances, the amount of cationic polyacrylamide had to be increased in order to achieve the same degree of pigment flocculation. The reason for the increase was due to the fact that the cationic polyacrylamide formed a polyelectrolyte complex with the anionic substances, namely sulfonated kraft lignin. The reaction between cationic polyacrylamide and lignin was found to be nearly stoichiometric. Low molecular weight cationic polyacrylamide formed mostly colloidal complexes while high molecular weight cationic polyacrylamide formed predominantly coacervate complexes; this was mainly due to differences in characteristic times of lignin association with the cationic polyacrylamide, clustering of polyacrylamide molecules and reconformation of polymer chains. / The performance of two-component retention aid systems consisting of a cationic polyacrylamide and anionic microparticles were evaluated by deposition of calcium carbonate filler on pulp fibers. Kaolin clay and bentonite were used to heteroflocculate polyacrylamide-covered surfaces of the fibers and pigment. Due to their inability to delaminate, kaolin clay and acid-treated montmorillonite showed no effect of calcium carbonate filler deposition. After cation exchange with sodium-rich solutions, which caused the montmorillonite to delaminate, the montmorillonite flocculation efficiency considerably improved. Kaolin clay neither delaminated after the cation exchange nor improved calcium carbonate deposition. Bentonite was found to completely delaminate when using polyacrylamide-treated fibers. When added to a suspension of fibers, filler and cationic polyacrylamide, bentonite was found to be in a form of stacks containing on average four platelets. / An alternative way to paper filling with pigment was tested on stationary sheets and on slow and fast Fourdrinier pilot paper machines. Using a secondary headbox on the pilot paper machines, a high degree of loading (above 30%) could be achieved using positive clay or calcium carbonate fillers. However, the fillers lowered the paper strength as they interfered with the fiber-fiber bonding in a similar fashion found in conventionally filled papers.

This study focuses on understanding the photochemical reactions that occur between ultraviolet stabilizers and lignin during irradiation in order to further comprehend the photo-protection mechanisms of these stabilizers during brightness reversion. The stabilizers chosen for study included a variety of ultraviolet absorbers (UVAs), in addition to a hindered nitroxide free radical (4-hydroxy-TEMPO). Irradiated samples were analyzed using quantitative 31P NMR, in addition to a technique known as 'Derivatization Followed by Reductive Cleavage'. / Benzophenone-based UVAs have been shown to be actively involved in photochemical reactions with lignin during irradiation, while benzotriazole-based UVAs are comparatively photostable under identical irradiation techniques. All additive combinations were found to inhibit the formation of carboxylic acids and photochemical condensation reactions in lignin; however, the joint application of 2,4-DHB and 4-hydroxy-TEMPO demonstrated synergistic inhibition of these reactions. / All additive combinations were shown to impede the formation of catechol structures and to retard the cleavage of lignin beta-arylether groups during irradiation. The combined use of Tinuvin 1130 and 4-hydroxy-TEMPO provided the most efficient inhibition of these reactions. These results provide insight into the excellent photoyellowing inhibition provided by this additive combination when applied onto mechanical pulps.