Cellulosic biomass materials have three principal
components: cellulose, hemicellulose, and lignin. Under
mild acid conditions and high temperature, the first two
components yield a variety of sugars: hexoses and pentoses,
which are subject to decomposition on continued exposure to
hot dilute acid. In the process hexoses yield
hydroxymethylfurfural (HMF) which,...
The bacterium most frequently used in microbial
leaching processes and studies is Thiobacillus
ferrooxidans. Applications of this bacterium include the
treatment of coal, low-grade ores and industrial solid
wastes for the solubilization of pyrite and other trace
metals associated with sulfides. The goal of this study
was the development of...
Hemicellulose hydrolyzate contains many carbohydrate
fractions, the most abundant being xylose, arabinose, and
glucuronic acid. Under mild acid conditions (0.025 -
0.10 M sulfuric acid) and high temperatures (140°C to
200°C) the first two components form furfural through a
series of dehydration reactions. Unlike xylose and
arabinose, glucuronic acid must...
Succinic acid, a low molecular weight dicarboxylic acid was used to leach out
heavy metals from Willamette Valley soil (contaminated separately with lead, copper,
and zinc) in form of water-soluble organo-metal complexes. The research tasks included
developing synthetic contaminated soils representative of those found at Superfund sites
and making heavy...
More than 30,000 potential Superfund sites have been identified. Heavy metals are contaminants at many of these Superfund sites. The average cost of cleanup a single-typical Superfund site currently stands at $20 million, and it is expected that the cost may escalate to $50 million within the next decade. Problems...
The effect of over-oxidation on periodate oxidation
of cellulose was studied. It was found that the over-oxidation
process has a significant effect on the overall
reaction. An integrated rate equation was formulated.
The oxidation of internal glucose units is second-order
overall, first order with respect to both periodate and
cellulose;...
Measurable surface parameters which may be related to the response evoked upon contact with biofluids have been suggested to provide direction for characterization, prediction, and ultimate control of biofluid behavior at interfaces. With respect to fouling of heat exchange equipment by biofluids, such properties may be useful for the development...
The effect of pH and ionic strength on the equilibrium adsorptive
behavior of β-lactoglobulin onto hydrophobic and hydrophilic
silicon surfaces was studied using ellipsometry. Plots of amount
adsorbed (μg protein/cm²) as a function of protein concentration
(mg/ml) exhibited attainment of plateau values beyond a protein
concentration of 0.250 mg/ml. At...
Ellipsometry was used to study the effects of surface energetics
and temperature on the equilibrium adsorptive behavior exhibited by
β-lactoglobulin. β-Lactoglobulin isotherms at 25, 37, and 55°C were
constructed for this purpose. The surfaces of acrylic, polycarbonate,
polyester, glass, and #304 stainless steel were contacted with protein
solutions of varying...
Illinois coal ground to 80-200 mesh was leached
with a low phosphate, high nitrogen medium containing a
mixture of Thiobacillus ferrooxidans and thiooxidans in a
fluidized bed. Coal slurries of 20-160 g/L were treated
in a 5 cm ID, 9.5 m high continuous loop bioreactor with
crossovers at top and...
The heat unit concept of time-temperature relationships
is used in this thesis as a means of studying the
temperature element of the climate at nine Oregon stations.
The stations, Astoria, Baker, Burns, Eugene, Medford,
Pendleton, Portland, Roseburg, and Salem, were selected on
the basis of distribution and availability of Weather...
This thesis treats the problem of enumerating equivalence
classes of Euler paths of full graphs. A full graph
is a complete, unordered, graph with no loops or repeated
edges. Two Euler paths are equivalent if and only if one
can be transformed into the other by a finite sequence of...
An algorithm is described for determining the vertices
and supporting planes (or lines) of the convex hull
of a given set of N distinct points in 3-space. The
method involves determining a finite sequence of convex
hulls, each successive convex hull being a better approximation
to the convex hull of...