Fusion excitation functions for the reactions of Sn-¹²⁴,Sn-¹³² with Ca-⁴⁰,Ca-⁴⁸ were measured at energies near and below the Coulomb barrier. Weak sub-barrier fusion enhancement accounted for by coupling to the first 2(+) and 3(-) states in the target and projectile was observed for Sn-¹²⁴,Sn-¹³² + Ca-⁴⁸. However, the Sn-¹²⁴,Sn-¹³² +...
The subject of this study was the determination of the changes
in photosynthesis, respiration and transpiration in two ecotypes of
Douglas-fir as caused by decreasing soil moisture content. The photosynthetic
rate was also correlated with the relative turgidities of
needles.
All the above processes were greatly affected by decreasing
soil...
The ecological and silvicultural importance of snowbrush,
Ceanothus velutinus, in the areas west of the summit of the Oregon
Cascades was studied. Particular attention has been given its nitrogen-
fixing ability under both field and greenhouse conditions.
On west slopes of the Oregon Cascades snowbrush occurs above
2, 500 feet...
Two-dimensional, primitive equation model studies of wind-forced flow over a continental shelf Show that, under upwelling conditions, high levels of near-inertial wave energy are found in the interior over the shelf. The regions of elevated wave energy, with maximum wave amplitudes of around ±0.2 m s⁻¹, persist for up to...
This thesis, a collection of creative non-fiction essays, explores the nature and influence of reading and school in the author's life. After a brief introduction explaining the title, part one describes the sensory dimensions of reading. Part two discusses the author's work as a student and teacher and the contradictions...
Sixty-day simulations of flow on the Oregon continental shelf are performed using the Blumberg and Mellor sigma coordinate, primitive equation model. The model is two-dimensional (an across-shelf section) with high spatial resolution and realistic shelf topography. Forcing consists of surface heat flux, either hourly or low-pass filtered wind stress, and...
Wood-plastic composites are generally presumed to be inherently more resistant to moisture uptake than solid wood, but there is little data on the relative rates of moisture uptake in these materials over time. Trex[R] and Strandex[R] deck sections were immersed in water for up to 215 days, then sections were...
A systematic investigation was made of the distribution of short wave radiation within the crown of an open-grown Douglas-fir tree. The study tree was 23 years old, 14 meters tall and had a maximum crown diameter of about ten meters. Global radiation was measured every 15 cm along eight different...
Past disasters such as mercury poisoning in Minimata, and new problems such as tributyltin impacts on shellfish have maintained public concern about problems caused by chronic discharges of hazardous materials into marine waters (Clark, 1986; U.S. Congress, 1987). However, hazardous chemical spills in coastal waters typically escape public attention. Unlike...
OBJECTIVES. Bioactive glass (BAG) is known to possess antimicrobial properties and release ions needed for remineralization of tooth tissue, and therefore may be a strategic additive for dental restorative materials. The objective of this study was to develop BAG containing dental restorative composites with adequate mechanical properties comparable to successful...