Theses and Dissertations at Montana State University (MSU)
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Item Freeze foaming: a novel process for the synthesis of foam ceramics(Montana State University - Bozeman, College of Engineering, 2018) Johnson, Nathaniel Peyton; Chairperson, Graduate Committee: Stephen W. SofieFoam is a class of materials that was developed only after World War II and ceramic foams are still in development. Many of the processes for synthesizing ceramic foam require the burning out of a polymer scaffold or the use of chemical reactions to generate pores. This thesis investigates the development of a novel synthesis approach called freeze foaming. In the freeze foaming process, pores are made by putting an aqueous solution under vacuum. The reduced pressure causes the air within the slurry to expand and form bubbles. Then once the foam is formed, it is frozen into place. Then the water is removed from the system through sublimation. Finally, the foam is densified by traditional sintering. After successfully creating ceramic foam samples, the parameters in the freeze foaming process were identified and investigated. Foam samples were characterized by taking density measurements, examining the macrostructure and microstructure with light microscopy, and determining mechanical properties through compression testing. In the end, highly porous foam samples with adjustable properties were synthesized using a novel manufacturing process.Item Identifying large herbivore distribution mechanisms through application of fine-scale snow modeling(Montana State University - Bozeman, College of Letters & Science, 2003) Messer, Mathew Adam; Chairperson, Graduate Committee: Robert A. GarrottItem Some experiments on the freezing and hardening of the adults of the Colorado potato beetle, Leptinotarsa decemlineata say(Montana State University - Bozeman, College of Agriculture, 1933) Salt, Reginald WilsonItem Influence of colostrum from safflower supplemented ewes on lamb cold tolerance and lamb growth(Montana State University - Bozeman, College of Agriculture, 2008) Robinson, Brenda Lee; Chairperson, Graduate Committee: Rodney Kott; Patrick G. Hatfield (co-chair)Five hundred, ninety-seven and 643 white face range ewes were used in a 2 year study, respectively, in a 3-way factorial arrangement to determine effect of supplemental linoleic oil on lamb serum metabolites, thermogenesis and lamb growth. During the last 45 ± 4 days of gestation ewes were group fed a daily supplement of either 0.23 kg·ewe-1·d-1 whole safflower seed (SS) or 0.34 kg·ewe-1·d-1 whole barley (C). Colostrum was collected from each supplement treatment and pooled according to treatment. At parturition, twin born lambs received either SS or C pooled colostrum. One h postpartum, lambs were placed in a 0°C dry cold chamber for 30 min. and lamb rectal temperature was recorded at one min intervals. Blood samples were taken prior to and after cold exposure. Lamb weights were taken at birth, turnout and weaning for growth. There was no difference (P > 0.10) in body temperatures between lambs born to ewes supplemented with SS vs. C or between lambs given pooled colostrum form SS or C supplemented ewes. At 0 minutes lambs born to SS supplemented ewes had lower glucose (P = 0.05), total protein (P = 0.05) and NEFA (P = 0.003) and higher BUN (P = 0.03) than lambs from C supplemented ewes. Lambs from SS supplemented ewes had lower NEFA (P = 0.01) after cold exposure (30 minutes). Total protein concentration was similar in year 1 but lower (P < 0.01) in year 2. Concentrations of aGP were higher in lambs from SS supplemented ewes at both 0 and 30 min in year 1. Lambs from SS ewes had higher (P < 0.01) blood aGP levels at both 0 and 30 min in year 1 than in year 2. No differences (P > 0.30) were detected between lambs from SS ewes vs. C for changes in any blood metabolites measured during cold stress period. No differences (P > 0.12) were detected for average date of birth, number of lambs born, number of lambs present at turnout and weaning or for weight of lambs at turnout or weaning for ewes receiving either SS or C supplements.Item The effect of exercising in the cold on markers of fluid balance in women(Montana State University - Bozeman, College of Education, Health & Human Development, 2011) Cornachione, Kristen Marie; Chairperson, Graduate Committee: Daniel P. Heil; John Seifert (co-chair)The purpose of the study was to examine the effects of a cold temperature environment on markers of fluid balance in women during submaximal exercise. Nine women completed a 90-minute submaximal cycling protocol in both a cold (-5°C) and temperate (24°C) environment. The dependent variables were heart rate (HR), systolic and diastolic blood pressure (SBP, DBP), ratings of perceived exertion (RPE), percent change in plasma volume (%DeltaPV), and percent change in body mass (%DeltaBM). A two-way RMANOVA was used to detect differences over time and temperature condition. Over time, HR, SBP, and RPE increased during exercise irrespective of temperature environment, while DBP did not change significantly. Between condition, %DeltaPV and %DeltaBM were significantly lower in the cold environment. The combination of results indicates that water is shifting out of the plasma volume, but is then being restored after termination of cold exposure and exercise.