Now showing items 2291-2310 of 3320

• #### Properties and performance evaluation of syntroleum synthetic diesel fuels

Synthetic fuels derived from natural gas or coal have been proposed as a replacement for the diminishing stock of fuels distilled from crude oil, and in addition offer significant environmental benefits. Fuels of this type are currently being produced and tested for their compatibility with existing diesel engines. This study examines the physical properties of the Syntroleum synthetic fuel produced by Syntroleum Corporation of Tulsa, OK, and its performance and energy balance in a Detroit Diesel series 50 engine generator. This is a high cetane fuel that contains predominately paraffins, and is essentially free of sulfur, olefins, metals, aromatics or alcohols. This work includes measuring physical properties: lubricity, density, cloud point, and heating value. Also discussed is the thermodynamic energy flow in a diesel generator system to determine what effect the new fuel has on electrical and heat production. In addition to the investigation of synthetic fuel, a similar kind of study was also performed on bio-diesel produced from fish oil.
• #### Properties of sodium sodium chloride brine on laboratory ice

Snow and ice surfaces are ubiquitous in the environment. Heterogeneous reactions on those surfaces are responsible for a wide range of phenomena such as the Antarctic stratospheric ozone hole, depletion of boundary-layer ozone, and deposition of mercury. Little is known about the location of impurities on ice surfaces or how that structure depends upon temperature and time after contamination. Therefore, we investigated microscopic structures created by depositing sodium chloride particles onto laboratory-grown ice below the hydrohalite-water eutectic temperature. As the temperature was increased above the eutectic, sodium chloride solution (brine) formed around the particle and spread across the air-ice interface. Literature indicated that ice crystal grain boundaries are the most thermodynamically stable site for brine; yet, on our time scale (minutes), the brine does not drain down the grain boundary and is instead present on the ice surface. Either the surface energetics of the system differ from expectations or a barrier inhibits the brine from moving down the grain boundary on the observational timescale. The area of the brine was used to relate surface coverage by our contamination mechanism to bulk composition. We find that brine does not fully coat the surface for typical snow properties.
• #### Protecting a Situk River fish camp way of life through visitor education: a community-based approach

Many sport fishermen who visit Yakutat understand little about the Situk-Ahrnklin Inlet set net fisheries. In Yakutat, these fisheries integrate commercial fishing with a subsistence fish camp way of life. This community participatory evaluation seeks to determine the usefulness of an interpretive sign and handout project aimed at alleviating a persistent visitor misconception that set net fishing is harming their ability to catch Situk River fish. It also explores what additional effort people in Yakutat think is needed to educate visitors about the set net fisheries. A combination of methods was used, including resident interviews, a community records search and a review of published research on the efficacy of visitor education tools. Interviews found widespread support for continuing visitor education efforts, including leaving the existing signs in place and reproducing additional copies of the handout. It was generally agreed that future materials should integrate information about the subsistence fishery. The importance of set netting for food, culture and income was emphasized. More interaction is needed to shift visitor outlooks closer to the community's shared connection to the river according to the participants. Interviews began the process of re-engaging people in a community effort to dispel visitor misconceptions. A multimedia approach, based on agreed messages using local strengths and assets, was preferred. It is hoped that this volunteer, community-based process will serve as another reason for reconvening Situk River partner agencies. A revived cooperative management framework is needed to implement a more sustained education effort, minimize user conflicts, ensure stewardship and rebuild trust between community members and government agencies.
• #### Protecting family drinking water in rural Alaska: improved water management in homes without running water

The objective of this study was to investigate and make recommendations for improved in-home water management in an underserved rural Alaskan community without piped water. The main focus of the study is point-of-use disinfection. A model was developed based on experiments to predict the chlorine decay over time and the necessary chlorine dosage for waters used in the pilot community so that sufficient chlorine residual would remain during storage. TOC concentration, initial chlorination level, reduced iron and temperature were major factors impacting the chlorine consumption. Safe free chlorine levels of between 0.2 mg/L and 4.0 mg/L could be achieved in a reasonable time and maintained for typical storage times, while avoiding unpleasant taste. A taste test in the community showed that levels of 1 mg/L or less could not be distinguished by most people and were acceptable for drinking. Storage and hand washing are likely major components of preventing microbial contamination. It was determined that closed containers do not slow the loss of disinfectant from evaporation. Thorough hand washing for at least one minute using soap and running water is recommended, since this was the most effective method to remove coliform bacteria from hands.
• #### Protective Factors Promoting Psychosocial Resilience In Biracial Youths

Resilience in adolescents is the achievement of positive outcomes and the attainment of developmental tasks in the face of significant risk. This study identified protective factors promoting resilience in the development of positive self-identity in biracial youths. The rapidly rising biracial youth population is a vulnerable group facing potentially higher risks for mental health and behavioral issues compared to their monoracial counterparts. Identity development, a central psychosocial task of adolescence, is a complex task for biracial youths since they must integrate two ethnic identities. For biracial youths, mastery of the psychosocial identity developmental task can be daunting as they face stressors such as racial stigmas and negative stereotypes, which may lead to identity problems manifesting during adolescence. Sixteen biracial individuals ranging from age 18 to 29 years participated in this qualitative research project. Comparisons were made to identify patterns and themes for factors affecting self-esteem and ethnic identity level among the participants. Brought to light were culturally-based protective factors stemming from individual, family, and social domains promoting psychosocial resilience in fostering healthy biracial identity resolution. Risk factors unique for the biracial population were also identified. The findings underscore the importance in understanding how the environment shapes and influences the ways biracial youth negotiate their dual identity. The research results can be integrated into appropriate prevention and intervention techniques for application by professionals and families to further healthy identity resolution in biracial youths.
• #### Protein Status Of Muskoxen And Caribou In Late Winter

The conservation and management of northern ungulates depends upon our understanding of the influence of habitat associations on the nutritional condition of individuals and population productivity. Adverse foraging conditions in late winter may reduce the availability of body proteins for reproduction. Therefore, assessing nitrogen (N) or protein status in late winter could be a valuable tool to monitor populations of northern ungulates. I collected >1,800 excreta samples to evaluate isotopic metrics of protein status [proportion of serum amino acid N derived from body N (p-AN), proportion of urea N derived from body N (p-UN), and the difference between the isotopic ratios of N (delta15N) in body tissues and urinary urea (DeltaBody-urea)] in captive and wild populations of muskoxen (Ovibos moschatus) and caribou (Rangifer tarandus) in late winter. I evaluated the dynamics of body protein and delta15N in a captive population of female muskoxen (2007). Diets and protein status were assessed in populations of wild muskoxen in northern Alaska (2005--2008); a semi-captive (penned) population of wild, pregnant caribou (2006); and wild populations of migratory and sedentary ecotypes of caribou (2006--2008). Captive female muskoxen lost body protein (~6%) in late gestation and these losses corresponded with the protein deposited in reproductive tissues. The concentration of plasma urea, the p-AN, and p-UN tended to increase throughout winter. During late gestation, most penned pregnant caribou on an ad libitum feeding schedule lost core body mass (55%) and were in negative protein status (54%). For groups of wild muskoxen (n = 30), abundance of preferred forages improved protein status (p-UN; R2 = 0.45). At the foraging sites of wild caribou (n = 32), the amount of shrubs in a lichen-rich diet had a positive effect on protein status (DeltaBody-urea, r2 = 0.26). Foraging constraints in late winter will decrease the amount of body proteins available for reproduction. However, considerable challenges remain to applying the p-UN as a monitoring tool at broad scales for caribou, but with appropriate consideration, isotopic proxies may be used to evaluate environmental constraints for northern ungulates at small scales.
• #### A protocol for assessing the impacts of urbanization on coho salmon with application to Chester Creek, Anchorage, Alaska

Coho salmon (Oncorhynchus kisutch) abundance has declined in many urban streams. The causes of these declines can be hard to identify because urban impacts on stream ecology are complex and can vary between watersheds. This makes it difficult to develop appropriate and effective strategies for stream rehabilitation or mitigation aimed at increasing coho productivity. To improve this situation I developed a habitat quality assessment protocol for urban coho salmon to help identify significant habitat degradation as a prelude to restoration planning. To evaluate the protocol I used it to assess coho habitat quality in Chester Creek, Anchorage, Alaska, an urban stream that once supported a large population of coho salmon but now only supports a remnant population. I compared habitat characteristics from one non-urban and two urban study reaches to 'healthy' standard guidelines. This application of the protocol showed that the most significant adverse effects of urbanization on coho salmon habitat in urbanized reaches were increased flood intensity, barriers to adult and juvenile migration, reduced physical habitat complexity, siltation of spawning gravels, stressful water quality conditions, and stocking of potential predators and competitors. These results provide useful information for prioritizing rehabilitation and mitigation efforts in Chester Creek.
• #### Proton transport and auroral optical emissions

The hydrogen lines are the characteristic emissions of proton aurora and have been used to study the impact of protons upon the atmosphere. Observations of hydrogen emission on the long wavelength side of the unshifted lines were not explained by previous theories. To explain the observed optical emissions, a numerical code is developed to solve the one dimensional, steady state, linearly coupled transport equations of H$\sp+$/H in a dipole magnetic field. For the first time, the mirror force is included in the transport equations to produce backscattered particles which are responsible for emission at wavelengths longward of the unshifted lines. Both downward and upward particle intensities of H$\sp+$/H are calculated. The mirror reflectivities of energy and particles are defined, and their dependences on proton input spectra and pitch angle distributions are studied. The results show that the mirror reflectivity increases both with characteristic energy and with pitch angle of the input proton flux, but is more sensitive to angular distributions than to energy spectra. Energy deposition rate, ionization rate, H$\sb\alpha$, H$\sb\beta$ and Nitrogen First Negative bands emission rates and profiles are calculated. Calculated fluxes of H$\sp+$/H and emission properties of Hydrogen Balmer lines are compared with a rocket measurement. The efficiency for production of the Balmer lines and the Nitrogen First Negative bands is obtained in terms of the energy input rate and the H$\sp+$ particle flux. A Doppler shift of about 3.0 A toward the blue for magnetic-zenith profiles of H$\sb\alpha$ is obtained, compared with observational results of $6.0 \pm 2.0$ A. The calculated emissions on the red side of the unshifted hydrogen atomic emission lines when convolved with the instrumental function accounts for the observed emissions on the long wavelength side of the unshifted hydrogen Balmer lines.
• #### Provenance and diagenesis of the Miocene Bear Lake Formation, Bristol Bay basin, Alaska

The Miocene Bear Lake Formation (BLF) is a prospective hydrocarbon reservoir exposed on the southwestern Alaska Peninsula, extending into the subsurface to the northwest (reaching 2,360 m maximum thickness). This study comprehensively characterizes composition of BLF sandstones, and develops important implications for varying reservoir quality. Unique integration of standard petrographic methods, electron microprobe analysis (EMPA), and ⁴⁰Ar/³⁹Ar dating of detrital hornblende strengthens interpretations by providing multiple lines of evidence and a more complete picture of composition, source units and terrane, and diagenetic history than possible with petrography alone. EMPA provides superior classification of volcanic rock fragments and identification of diagenetic minerals. Results indicate a pressure-controlled diagenetic system, and a provenance more complicated than recycling of older strata, as currently interpreted. Simultaneous derivation from the Meshik Volcanics and recycling of Tolstoi, Chignik, and Naknek formations suggests erosion of a structurally-deformed source terrain (e.g. reverse-faulted anticlines). Abundance patterns of pore-filling zeolites, calcite, albite, and kaolinite likely represent variations in Pco₂ caused by variations in burial depth. Optimal reservoir quality is likely present in the subsurface upper BLF along the northwestern coast (and deeper in the basin), where sandstone composition is presumably more quartz-rich, less volcaniclastic, and has experienced higher Pco₂ fluid migration.
• #### Proximate and ultimate control of reproductive effort in northern shovelers (Anas clypeata) nesting at Minto Flats, Alaska

The purpose of this study was to examine factors that influence reproductive effort of female Northern Shovelers (Anas clypeata) nesting at Minto Flats, AK during summer 1991-1993. I investigated the importance of endogenous nutrient reserves to females during egg production and examined changes in organ weights and intestine lengths through the reproductive cycle. Changes in organ weights and intestine length were similar to those of shovelers nesting in Manitoba. Females used neither somatic lipid reserves, protein reserves, nor mineral reserves to produce eggs. Individual variation in somatic lipid reserves was explained by body size and nest initiation date, while variation in somatic protein reserves was explained by standardized nest initiation date. Somatic mineral variation was explained by differences among years. Neither somatic protein nor mineral reserves were reduced during incubation, but somatic lipid reserves decreased significantly. I conclude that endogenous nutrient availability does not proximately limit clutch size during laying for this population, possibly due to high productivity of interior Alaska wetlands and long days. Little is known about nest attendance behavior of ducks in the subarctic; therefore, I examined shoveler nest attendance patterns at Minto Flats to determine if observed patterns differed from those documented for shovelers nesting in Manitoba, Canada. Shovelers nesting at Minto were less attentive and took more frequent, longer recesses than shovelers in Manitoba. I examined patterns of nest attendance during incubation in relation to clutch volume and female weight loss to determine if females make tradeoffs between energy invested in the clutch and energy invested in incubation. I found no evidence of energetic tradeoffs by Shovelers nesting at Minto Flats. To determine if the trait of synchronous hatching could limit clutch size for a species of the genus Anas I measured development time and metabolic rates of Mallard (Anas platyrhynchos) eggs incubated in a constant environment. Females varied in length of time their eggs required to reach the star-pipped stage of hatch. Metabolic rate of eggs varied positively with position in the laying sequence and varied among females. These results indicate that metabolic rate may act as a synchronization mechanism for hatch.
• #### Prudhoe Bay West End gas lift supply optimization

The western extension of Alaska's Prudhoe Bay, known collectively as Eileen West End (EWE), operates under a gas lift pressure supply constraint. This constraint is largely contributed by two factors: the extensively long gas lift supply line that stretches across the western field and the large number of production wells offtaking gas lift to stay online or enhance production. The gas lift supply line is approximately 18.5 miles long and provides gas lift to 200+ production wells. This results in a pressure drop severe enough to start hindering production on the western most side of the field as low gas lift supply pressure can cause unstable production, reduced production rate, or stop production altogether. Theory suggests that boosting the system's gas lift supply pressure will improve production from the field. In order to quantify the benefit of boosting the gas lift supply pressure and determine the most optimal way to do so, an industry proven physics based multiphase flow simulator was used to construct two models, a production system and a gas lift system. This dual integrated model approach enabled the ability to capture and predict production effects caused by changes in gas lift supply pressure and determine if boosting the pressure will be beneficial from an operator standpoint. The objective of this project is to describe how building an integrated production model can capture and quantify changes in production for a very large and complex interconnected system. Applying these types of models can help steer important operational and economic decisions to minimize risk and expense as an operator. Using the models, several scenarios were evaluated to determine and quantify the most optimal approach to address the low gas lift supply in EWE. It was determined that shutting in the least competitive wells to boost the gas lift supply pressure was the best scenario to implement for several reasons: the scenario still yielded a high production benefit, it did not have any investment requirement, and the actions could be reversed if a negative impact was realized.
• #### Public use of local foods in the Tanana Valley: understandings of producers and low-income community members

This thesis explores factors that affect local food use in the Tanana Valley region of Alaska. Alaskan public discourses increasingly link local food production to a more sustainable and secure state and community food supply. However, current local food system development in the United States is marked by signs of socially unequal distribution of the benefits of local food. In Spring 2011, semi - structured interviews and focus groups were conducted with agricultural producers and community members affiliated with the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), and the Farmers' Market Nutrition Program (FMNP). Results show that local food use is complex and tied to livelihood and daily concerns of both producers and consumers. Producers highlighted challenges in food production, and characterized public use of local foods as limited by insufficient production. WIC employees and FMNP recipients viewed convenience and cost as important determinants of local food use. This exploratory study contributes to a more complex understanding of the local food system in the Tanana Valley through close examination of the perceptions and life experiences of human actors in this food system.
• #### Putative pheromones in the urine of male moose: evolution of honest advertisement?

I tested hypotheses about how olfactory communication is related to mating behavior in Alaskan moose (Alces alces gigas). Males dig rutting pits where urine is deposited to which females strongly respond. Consequently, male urine may contain primer pheromones that synchronize estrus of females. Urine samples were collected from captive moose on the Kenai Peninsula, Alaska. Samples included those from the mating season and from the nonrutting period for two adult males, one yearling male, and one male and one female calf. After pH adjustment, samples were extracted with methylene chloride to yield 3 fractions (acidic, neutral, and basic), which were analyzed by gas chromatography-mass spectrometry. Putative pheromones include unsaturated alcohols and homologs of tetrahydro-6-methyl pyranone, and 2-nonen-4-one. I hypothesize that these compounds are related to hypophagia and catabolism of body reserves by rutting males, and thereby provide an honest advertisement of body condition in moose.
• #### Qik'rtam Litnauwistai (island's teachers)

Qik'rtam Litnauwistai (Island's Teachers) was a multi-tiered, community-based, participatory action research project initiated as a direct response to both community and institutional recommendations to "grow our own" Alutiiq educators. The study (a) examined current departmental practices in teacher education at Kodiak College, (b) sought community feedback through interviews regarding recruiting and retaining Alaska Native pre-service teachers on Kodiak Island, and (c) analyzed successful eLearning course completion data, based on synchronicity. The examination and focus of improvement was on the educational system and program delivery model to meet the needs of all teacher candidates, especially our future Alutiiq educators. Interview participants overwhelmingly felt it was important to "grow our own" Kodiak teachers who could (a) provide a role model, (b) have teachers who possessed and could share a high level of cultural understanding, (c) who could understand the local environment in which they worked, and (d) provide a way to strengthen the community in which they live. Based on a review of literature, interviews, and data from UAA, recommendations or considerations for changes are suggested for (a) the Kodiak College Education faculty, (b) Kodiak College, (c) the University of Alaska Anchorage, and (d) Kodiak Island Borough School District.