Published August 1980. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Methane is a product of biogeochemical processes which respond to changes in climate. The history of atmospheric methane is recorded by ice cores providing insight into past changes in these biogeochemical processes. This dissertation is comprised of three studies which focus on centennial- and millenial-scale variability of methane from ice...
New ice cores retrieved from the Taylor Glacier (Antarctica) blue ice area contain ice and air spanning the Marine Isotope Stage (MIS) 5/4 transition, a period of global cooling and ice sheet expansion. Chronologies were determined for the ice and air bubbles in the new ice cores by visually matching...
The variable length, six-electrode plasma source for atomic
emission spectroscopy described here is operated from three
compact, simple, and inexpensive direct current power supplies. The
vertical arcs formed between the three electrode pairs completely
entrain the sample and are typically operated at 40 V and 20 A.
Three concentric quartz...
Ice cores are considered the gold standard for recording past climate and biogeochemical changes. However, gas records derived from ice core analysis have until now been largely limited to centennial and longer timescales because sufficient temporal resolution and analytical precision have been lacking, except during rare times when atmospheric concentrations...
Spectrometric detection systems for gas chromatography
(GC) based on gas phase ultraviolet absorbance
and fluorescence measurements have been developed and
evaluated in this research. Polynuclear aromatic compounds
(PNAs) are selectively detected by these systems.
Limits of detection for PNAs range from 4 ng to 90 ng
for absorbance determinations, and...
A method of treating resonance captures for few energy group
calculations is developed using the Narrow Resonance-Infinite
Absorber approximation to the resonance integral. The application
of this method is not restricted to this approximation, however,
as other approximations to the resonance integral could also be
used.
The approach presented defines...
Forest composition in Paraguay has been in a state of change for the past half century due to land management practices, forest fragmentation, and deforestation for agriculture. How these factors affect dendrological diversity and wood anatomy in Paraguay is not well understood. This thesis documents Paraguayan forest composition on the...
Fuel loading patterns which have a minimum power peak are
economically desirable to allow power reactors to operate at the highest
possible power density and to minimize the possibility of fuel
failure. A computer code called SHUFLE was developed for pressurized
water reactors which shuffles the fuel in search of...