This dissertation presents the results of a research effort conducted to better understand the seismic performance and analysis of pile-supported wharves. Given the limited number of well-documented field case histories, the seismic performance of pile-supported wharves has been poorly quantified, and the analysis methods commonly employed in engineering practice have...
The seismic performance of port structures has been well documented following
recent earthquakes, and indicates that port structures are highly susceptible to earthquake-induced
damages. These damages are primarily due to soil liquefaction and the associated
ground failures. Sheet pile bulkheads provide vital intermodal and lifeline transportation
links between water-side and...
Originally used as a method to densify loose soils, controlled blasting has expanded its applicability to geotechnical engineering by becoming a research tool to physically generate liquefaction for full-scale in-situ tests, ranging from seismic performance of deep foundations to evaluating ground improvement techniques. Current methods used to design the blasting...
Sulfur is one of the six elements required during the early stages of the evolution of life, and enzymes involved in sulfur transfer and oxidation are increasingly being recognized as potential drug targets for antimicrobials as well as for therapies for cancer, neurodegenerative and inflammatory diseases. Bacteria are able to...
Measurements on growth traits up to 41 years of age
from 68 progeny sites in eight first-generation breeding
zones of coastal Douglas-fir (Pseudotsuga menziesii
[MIRB.] FRANCO var. menziesii) in the US Pacific Northwest
were used to investigate age trends of genetic parameters
and to determine optimum age of selection. Heritabilities...
The purpose of this research was to measure the copper-binding behavior of Dissolved Organic Matter (DOM) contained in Pulp and Paper (P&P) wastewater effluent and evaluate the Biotic Ligand Model’s (BLM) ability to quantify copper speciation in P&P influenced waters. A copper ion selective electrode was used to measure copper...
Heavy metals, such as copper, zinc, and cadmium, are ubiquitous in stormwater and potentially toxic to aquatic organisms at low concentrations. Removal of heavy metals contamination by conventional treatment is expensive and does not always reduce metals concentrations low enough to ensure safety of all aquatic species. This research seeks...
In order to better predict the aggregation state of nanomaterials, the factors that influence aggregation must be understood. The combined effects of natural and engineered coatings have been shown to factor into nanoparticle aggregation behavior in preliminary research. In this study, aggregation behaviors of gold nanoparticles with two different engineered...
Low concentrations of dissolved copper have been shown to adversely
affect the olfactory system of endangered salmonids, impairing their ability to avoid predators and likely increasing predation. It is believed that only the free ionic (Cu2+ free) and weakly complexed forms are bioavailable to organisms; these forms typically account for...
The production of the fullerene C60 and its emerging applications in consumer
products imply its ultimate release to the environment. Due to the molecule’s relative
novelty, the aqueous characteristics of C60 have not been fully assessed, though it may
potentially harm human or ecological health. C60 is highly insoluble in...
The fate and transport of engineered nanoparticles (ENPs) such as titanium dioxide (TiO₂) are of concern due to their increasing use in consumer products. Although analytical methods for detection and quantification of ENPs in environmental matrices are being developed, these methods are difficult, time consuming, and not easily validated for...
The adsorption of natural organic matter (NOM) to the surfaces of natural colloids
and engineered nanoparticles is known to strongly influence, and in some cases control,
their surface properties and aggregation behavior. As a result, the understanding of
nanoparticle fate, transport and toxicity in natural systems must include a fundamental...
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Jeffrey A. Nason
The adsorption of natural organic matter (NOM) to the surfaces of
Recent studies have discovered that salmon, specifically juvenile Coho Salmon, have their olfactory senses inhibited by the presence of low concentrations of copper concentrations at very low concentrations. Much of this copper is deposited on roadways by car brake pads during their use. The copper is carried with stormwater into...
The widespread use of engineered nanoparticles (ENPs) in industrial applications and consumer products makes their release to the environment inevitable. Understanding the aggregation behavior of ENPs is crucial to understanding their fate, transport and toxicology in aquatic systems. This study investigated the comparability of experimentally-determined and model-estimated attachment efficiencies for...
Current best management practices (BMPs) for stormwater treatment are not able to adequately remove heavy metals to levels which do not adversely affect aquatic life. Copper is commonly found in highway stormwater runoff, with the primary source being brake pad wear. Copper is of particular concern due to inhibitory effects...
Microplastics (MPs) are plastic particles less than 5 mm in diameter. These contaminants are increasingly found in the environment due to increased plastic production, use, and improper disposal. Detecting and measuring these contaminants in the environment has proven difficult, requiring the use of fate and transport models to assess MP...
Nanoparticles are becoming increasingly important in numerous technological fields but evidence shows that they can be toxic to many organisms. To predict their fate and transport in the environment, nanoparticle attachment to naturally occurring colloids must be examined. This study investigated citrate-capped gold nanoparticle (Cit-AuNP) heteroaggregation with two model colloids...
Low levels of copper have been shown to impair the olfactory system of threatened and
endangered (T&E) salmon, decreasing their predator avoidance behavior and likely
increasing mortality. However, only dissolved copper (dissCu) present as the cupric ion
(Cu2+) and weakly complexed species are truly bioavailable. Previous studies indicate the
vast...