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Diamondoid 2-Substituted 1,3-butadienes: Synthesis and Characterization of Thermal and Mechanical Properties
No full textAn improved monomer synthesis for diamondoid 2-substituted 1,3-butadienes is presented. Heterogenous dehydration of 2-(1-adamantyl)-3-buten-2-ol using Amberlyst®-15 cationic exchange resin at ambient temperature gave 2-(1-adamantyl)-1,3-butadiene (1) in excellent yield. An improved UV photoacetylation of diamantane was also identified and the dehydration of 2-(4-diamantyl)-3-buten-2-ol afforded 2-(4-diamantyl)-1,3-butadiene (2) in good yields. Overall, heterogeneous dehydration with Amberlyst®-15 presents an attractive monomer synthesis route for diamondoid 2-substituted 1,3-butadienes in quantities necessary for comprehensive polymerization studies. Emulsion polymerization of 1 and mixtures of 1 and isoprene was carried out at room temperature using redox pair-type hydroperoxide initiator. All poly(1) and poly(1-ran-isoprene) samples were soluble in common organic solvents and exhibited high 1,4-microstructure. A continuous increase in glass transition temperature (Tg) from -63 to 172°C was observed by increasing the ratio of 1 in the comonomer feed of poly(1-ran-isoprene), and Tg values were in good agreement with the Fox equation. After complete hydrogenation to poly(1-vinyladamantane-alt-ethylene-ran-propylene-alt-ethylene) a continuous increase in Tg was observed from -55 to 152°C. The high solubility and improved access to 2-(1-admantyl)-1,3-butadiene open the door for the exploration of diene polymers with enhanced high temperature properties. The first mechanical characterization of the poly(1) and the rubbery poly(1-ran-isoprene) system is reported here. Bulk samples were hot pressed and analyzed with dynamic mechanical analysis in a 3-point bend geometry. In conjunction with rheometry, a more complete characterization of the glass transition, rubbery plateau, and rubbery flow regions with respect to wt% of 1 was achieved. Rheology of poly(1) before and after complete hydrogenation of the backbone was performed to understand the effect that backbone rigidity has on flow properties. Nitroxide mediated polymerization was investigated as a potential route for poly(1) block copolymers. However, it was determined that the formation of monoterpene side products was favored at required reaction temperatures. A novel living anionic polymerization technique using 4,5-methylenephenanthrene an indicator to titrate impurities prior to initiation with sec-butyllithium was then used to synthesize poly(1) and poly(1-block-isoprene). A comparison of anionic to emulsion poly(1) prompted an investigation into the insolubility of the former. Powder x-ray diffraction experiments revealed distinct diffraction peaks in anionic poly(1). NMR and GPC analysis suggests the presence of branching in emulsion poly(1) while anionic poly(1) was confirmed to be completely linear. It is hypothesized that branching in emulsion poly(1) contributes its observed solubility.doctoral, Ph.D., Chemical and Materials Science Engineering -- University of Idaho - College of Graduate Studies, 2021-0
Lower Extremity Joint Stiffness Associated with Drop Jump Performance: Differences in Genders and Athletes
No full textA vertical jump task is often performed in combination with a preceding movement which targets activation of the stretch-shortening cycle by a series of eccentric and concentric muscle contractions. Properties of the soft tissues involved can be altered by an athlete’s training program, which may enhance their ability to effectively transfer stored elastic energy to maximize performance. Joint stiffness represents the potential ability of an individual joint to resist the external load and contribute the combined lower extremity resistance to an external load. The connection between joint stiffness and jump performance is related to the ability of the structures to store and return of elastic energy through potential manipulation to the angle-moment relationship. Joint stiffness is typically represented by the slope of the line of best-fit obtained by a linear regression model, which indicates the average joint stiffness throughout the entire eccentric or contact phase. However, the linear regression method did not fully represent the curvilinear angle-moment relationship of specific joints during the drop jump task, suggesting that joint stiffness should be calculated using a curvilinear relationship. Furthermore, it was found that the eccentric phase was more accurately represented when the eccentric phase was subdivided into loading and absorption subphases. Therefore, the overall purpose of this dissertation was to investigate the potential relationship between joint stiffness and drop jump performance with the application of a novel method to calculate joint stiffness. To address this purpose, three separate manuscripts were conducted generated from by two independent data collections. The benefits of utilizing a 2nd order polynomial regression model when calculating lower extremity joint stiffness incorporating subdivided eccentric phases was addressed in the first manuscript. The polynomial regression model had greater goodness-of-fit than the linear regression model for all joint stiffnesses. Differences were found between the two models for hip and knee stiffness during the loading and absorption phases. These results suggest that the polynomial regression model is a more accurate representation of the angle-moment relationship while subdividing the eccentric phase a drop jump into phases. Sex differences in lower extremity joint stiffness during vertical drop jump performance and potential sex differences between this relationship were the focus for manuscript two. Males had greater hip and ankle stiffness during the loading phase, knee stiffness during the absorption phase, GRF2, net jump impulse, and jump height than females regardless of box height. The 60 cm box increased all joint stiffnesses during the loading phase, knee and ankle stiffness during the absorption phase, and GRF1. Hip and knee stiffness during the loading phase predicted jump height of females whereas the joint stiffness was not related to males’ jump height. These results suggest that females have different lower extremity joint stiffness strategies than males to achieve the drop jump. The primary purpose of the final study was to examine differences in jump performance and joint stiffness between groups of female collegiate athletes (Basketball/Volleyball: BV, Dancers: DAN, Soccer: SOC). A secondary purpose was to identify the relationship between drop jump performance and both joint stiffness and isokinetic strength. The BV group had significantly greater jump height and jump impulse with reduced hip joint stiffness during the loading phase than the DAN group. No differences in isokinetic strength were observed between groups. Hip concentric and knee eccentric extension peak torque were significant independent variables within the overall regression model (p doctoral, Ph.D., Movement & Leisure Sciences -- University of Idaho - College of Graduate Studies, 2021-0
Upcycling Mixed Plastic Waste into Composites and Fuel
No full textAbstract The growing concern with regards to the amount of mixed plastic waste (MPW) especially in municipal solid wastes (MSW) and with the significant quantity ending up in the landfill has led to search for more sustainable mode of disposal. MPW are the non-recyclable fraction after sorting and it is comprised of single use items, such as packaging, and plastic recycling grades 3-5 generated. Mechanical and chemical recycling can divert these wastes especially MPW containing some paper fibers from the landfill. This study evaluated the mechanical, thermal, and rheological properties MPW in combination with fibers derived from residual hop bines and coupling agents to form composite materials and secondly the thermal deconstruction (pyrolysis) of MPW into liquid fuel. MPW were used to formulate composites. To improve the interfacial bonding between MPW and fibers, maleated polyolefin (MAPE) and glycidyl methacrylate polyolefin were evaluated as coupling agents, while dicumyl peroxide (DCP) was evaluated as a long chain branching and grafting agent in the formulations. The use of the coupling agents, especially MAPE, was observed to increase interaction between the polymer matrix and fiber leading to a better performance in tensile strength. The addition of DCP to the MPW formulations slightly reduced its tensile strength probably due to polymer chain scission. The addition of hops fiber improved the tensile modulus of the composites relative to MPW. For chemical recycling, the homogenized MPW was pyrolyzed (with and without Zeolite Y catalyst) between 500 to 600 °C in a tube reactor. Liquid products were trapped and characterized using a combination of GCMS and ESI-MS. The physical and chemical characteristics of the solid char product were also characterized by FTIR spectroscopy. Pyrolysis products were mainly straight chain hydrocarbons, while catalytic pyrolysis products were short-branched hydrocarbons and aromatics. These results clearly show that catalytic pyrolysis was successful in producing a liquid fuel comparable to gasoline.masters, M.S., Environmental Science -- University of Idaho - College of Graduate Studies, 2021-1
A Field Device to Rapidly Determine the Bending Strength of Maize Stalks
No full textBillions of dollars’ worth of maize are destroyed across the world every year by high winds, hail, and other natural phenomena. Historically, plant breeders and farmers have been unable to prevent these losses using selective breeding because no reliable method for determining stalk strength was available. Recent innovations have seen several devices and methods created to determine stalk strength, but each has its downsides. One of the more promising methods is the use of puncture tests, which puncture maize stalks with a needle and record the displacement and force of the needle. The data from these tests is then analyzed to extract important information about the stalk geometry. Experiments have shown that this method for determining stalk strength is highly correlated with more direct and destructive methods of stalk strength analysis. However, these tests have only been performed in a lab setting with heavy and expensive equipment. The Stalk Puncture Device (SPuD) is a novel handheld, battery operated, unit capable of performing nearly 100 puncture tests an hour. This device costs a fraction of the price of the standard lab equipment and allows users to test stalks in vivo. Initial tests of the device during validation are promising and show strong correlation with data from lab equipment. Hardware and software improvements were identified during validation that will likely improve these correlations further in the future.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2021-1
Water-Energy Nexus Modeling in Cooling Towers and Hot Springs
No full textWater and energy resources are essential to humanity’s existence which have shaped society's development. The limited water and energy resource forced humans to seek new ways to use them more efficiently. The recent increase in water and energy demand makes any water and energy conservation effort very valuable. In the absence of conservation efforts, providing sufficient supplies of these resources may not be applicable in the future. The present thesis found two applications for implementing a more efficient approach to their operation for water and energy conservation purposes.Cooling towers are equipment for dissipating the excess heat by water evaporation. The study elaborates on the role of cooling tower modeling in implementing any water and energy consumption improvement plan by presenting a modeling approach, categorizing various methods of modifying water and energy consumptions through past studies. To map the future studies, summarize and organize the past efforts and find future research trends for upgrading water and energy usage in cooling towers have been done. The practical approaches to save water and energy such as design cooling tower based on the ambient air conditions, add dry section to existed wet cooling tower, and employ variable frequency drive fans in forced draft cooling tower have been proposed. An improvement plan has been implemented on the existed mechanical draft wet cooling tower located at the main campus of University of Idaho by using Data Acquisition Device (DAQ) and ambient air condition real data. By adjusting outlet water temperature in the cooling tower developed model, the cooling towers load can be managed, which reduces its water and energy consumption. Consequently, the improvement plan reduced cooling tower fans energy consumption and water loss due to evaporation. For one month of operation of the improved plan, up to 28035.50 kWh energy saving, 179.49 m3 of water saving, and $1125.17 cost savings have been recorded. The present thesis found low-temperature geothermal energy sources such as hot springs distributed in different areas as a potential for implementing small-scale energy plants for indirect energy usage. A techno-enviro-economical tool has been developed to approximate the technical, economic, and environmental aspects of hot spring power plant projects, including power generation capacity, initial investment, and possible income from the power plant. The developed technical model estimated the hot springs power generation plants from 9.3 kW to 303 kW depending on the temperature and water discharge mass flow rate. The developed economic model calculated the payback period of investing in a hot spring energy plant as low as six years, which is better cost-effective than other geothermal energy plants.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2021-1
Physiochemical Properties of Pulse Protein Isolates Based on Isoelectric Extraction
No full textThere is an increasingly growing interest in plant-based proteins and one of the most popular type of crops used to extract protein from are pulse crops. Through the use of an isoelectric focused protein extraction process with yellow peas, red lentils, chickpeas and great northern beans the optimal isoelectric pH conditions were determined along with the isoelectric conditions used that led to the highest protein content and greatest physical and chemical properties of the protein isolates.masters, M.S., Food Science -- University of Idaho - College of Graduate Studies, 2021-0
A Grid Partition-based Local Outlier Factor for Big Data Stream Processing
No full textOutlier detection is getting significant attention in the research field of big data. Detecting the outlier is important in various applications such as communication, finance, fraud detection, and network intrusion detection. Because of their unique characteristics, such as large volume and high velocity, data streams pose a challenge to traditional outlier detection methods. Local Outlier Factor (LOF) is one of the most appropriate techniques for determining outliers in the density-based method. However, it faces some challenges when dealing with the data stream. One issue is that LOF requires the entire dataset as well as the distance value to be stored in the computer memory. Another issue arises when a change occurs in the dataset, which necessitates a significant recalculation from the beginning. To address these issues, this dissertation proposes a new method for detecting local outliers in data streams called the Grid Partition-based Local Outlier Factor (GP-LOF). We improve the GP-LOF algorithm even further by adding another technique known as the Local Outlier Factor by Reachability Distance (LOFR). The improved algorithm is thus called the Grid-Partition-based Local Outlier Factor by Reachability Distance (GP-LOFR). We tested both GP-LOF and GP-LOFR with several benchmark datasets. They outperformed the Density Summarization Incremental Local Outlier Factor (DILOF) algorithm, which is the most representative algorithm in existing studies of data stream processing. We also worked with real-world datasets of concrete mixture. In that work, a new algorithm called the Isolation Forest based on a sliding window for the Local Outlier Factor (IFS-LOF) was developed. The IFS-LOF outperformed both LOF and LOF-Sliding Window (LOF-SW) in accuracy of the results. In summary, the three new algorithms GP-LOF, GP-LOFR, and IFS-LOF are the major contributions of this PhD research. All proposed algorithms work without any previous knowledge of data distributions and are capable to execute with limited computer memory. This PhD research makes a solid contribution to the field of local outlier detection in big data streams. In the near future, we will extend the developed algorithms by applying Evolution Computation (EC) methods to further improve the accuracy and reduce the execution time. Moreover, we will apply these algorithms to more real-world datasets.doctoral, Ph.D., Computer Science -- University of Idaho - College of Graduate Studies, 2021-0
Presence in Virtual Environments: Visual Factors and Measure Convergence
No full textN/Adoctoral, Ph.D., Psychology -- University of Idaho - College of Graduate Studies, 2021-0
Assessment of the impacts of prescribed fires on soil quality and cultural impacts of interdisciplinary collaboration
No full textdoctoral, Ph.D., Water Resources -- University of Idaho - College of Graduate Studies, 2021-0
Reconstructing Eocene Paleotopography of the Northern U.S. Cordillera Using Stable Isotope Paleoaltimetry of Hydrated Volcanic Glass
No full textTopography controls regional drainage patterns, sediment transport, resource accumulation, climate, and atmospheric circulation. In turn, topography is controlled by plate tectonic forces and crust and mantle processes, such as compression, delamination, extension, heating, and magmatism. In studying the surface record, researchers can estimate past elevations, the timing of surface uplift or lowering, and the regional extent of highlands, which are needed to characterize the lithospheric processes and conditions responsible for changes in surface topography. In the complex tectonic setting of the northwestern United States, paleoelevation records can help interpret the timing and processes behind Rocky Mountain orogenesis. During the Eocene (ca. 56-34 Ma), the northern U.S. Cordillera experienced a shift from compression and Laramide-style thrusting to extension, recorded in extensional basin formation, exhumation of metamorphic core complexes, and southwestward migration of magmatic activity, accompanying surface uplift in the fold-thrust belt and elevated Sevier hinterland. However, researchers disagree on the extent, lifespan, and elevation of this highland or how the region evolved into the modern Rocky Mountains. I used stable isotope paleoaltimetry of Eocene-age hydrated volcanic glass shards collected along a longitudinal transect from the western paleoshoreline to the Great Plains to determine estimates and locations of high topography associated with this period of Rocky Mountain surface uplift and lowering. Volcanic glass acts as a proxy for the long-term average δD value of paleo-meteoric water at the time of glass deposition. I analyzed ancient meteoric water preserved in volcanic glass samples of known or inferred age across the study area to create Paleogene paleotopographic profiles across the range. Glass hydrogen isotopic ratio (δDglass) values from samples from fluvial and alluvial sections range from -223.6‰ ± 2.4‰ to -89.0‰ ± 6.9‰VSMOW. The most D-depleted samples are consistently found in west-central and southwest Montana, and yield modeled paleoelevations of 4640 +720/-440 m in the early Eocene down to 3400 +520/-540 m in the late Eocene - Oligocene. From these data, I find that topography was long-standing throughout the Paleogene, despite surface lowering by ~1200 m by the Oligocene. Because high Eocene pCO2 would have reduced isotopic lapse rates, these values are minimum paleoelevation estimates. A combination of crustal thickening from recent shortening and thermal/geodynamic effects from Farallon slab rollback, delamination, and/or high heat flow from regional volcanic activity are responsible for the development of Paleogene northern U.S. Cordilleran paleo-highs.masters, M.S., Geology -- University of Idaho - College of Graduate Studies, 2021-0