Neptunium, with its rich redox chemistry, has a special position in the chemistry of actinides. With a decades-long history of development of aqueous separation methods for used nuclear fuel (UNF), management of neptunium remains an unresolved issue because of its not clearly defined redox speciation. Neptunium is present in two,...
Low temperature cracking is attributed to tensile stresses induced in an
asphalt concrete pavement that develop when the pavement is subjected to a cold
temperature. Cracking results in poor ride quality and a reduction in service life of
the pavement. Low temperature cracking has been predicted by regression
equations, mechanistic...
A microfluidic nanofiltration module has been designed, fabricated and applied to the continuous-flow, pressure-driven, post-synthetic purification of macromolecules and nanoparticles via diafiltration using a commercially available organic solvent resistant nanofiltration membrane, STARMEM 122. This module will readily interface with other microscale components within a
"nanofactory" for the rapid synthesis, purification...
This study investigated the use of radon-222 as an in situ partitioning tracer for quantifying nonaqueous phase liquid (NAPL) saturations in the subsurface. Laboratory physical aquifer models (PAMs), field experiments, and numerical simulations were used to investigate radon partitioning in static (no-flow) experiments and in single-well, 'push-pull' tests conducted in...
Two separate research projects are described here. One involves
development of a new analytical method for determination of Ba in seawater and
other natural waters. The other is a collaborative field study of the chemistry of
Lake Issyk-Kul, Kyrgyzstan.
The method project explored an ion chromatography-fluorescence detection
bench-top approach for...
The spatial organization of farm units in Polk and Linn counties
in the mid-Willamette Valley has undergone significant change over
the past 30 years. Whereas most study areas operations in the
1930's and 1940's consisted of small family owned farms with contiguous
land bases, present mid-Willamette Valley units vary considerably...