Ethylene oxide (EO) is a very versatile compound with considerable energy in its ring structure. Its reactions proceed mainly via ring opening and are highly exothermic. Under some conditions, it is known to undergo a variety of reactions, such as isomerization, polymerization, hydrolysis, combustion and decomposition Due to its very reactive characteristic and widely industrial applications, EO has been involved in a number of serious incidents such as Doe Run 1962, Freeport 1974, Deer Park 1988 and Union Carbide Corporation’s Seadrift 1991. The impacts can be severe in terms of death and injury to people, damage to physical property and effects on the environment. For instance, the Union Carbide incident in 1991 caused one fatality and extensive damage to the plant with the property damage of up to 80 million dollars. Contamination has a considerable impact on EO reactivity by accelerating substantially its decomposition and playing a key role on EO incidents. In this work, the reactivity of EO with contaminants such as KOH, NaOH, NH4OH, and EDTA is evaluated. Useful information that is critical to the design and operation of safer chemical plant processes was generated such as safe storage temperatures (onset temperature), maximum temperature, maximum pressure, temperature vs. time, heat and pressure generation rates as a function of temperature and time to maximum rate using adiabatic calorimetry. A special arrangement for the filling-up of the cell was constructed due to the gaseous nature and toxicity of EO. A comparison of their thermal behavior is also presented since several contaminants are studied.

This study examined the motivational state associated with smoking craving specifically among women and the effect of deprivation and smoking status on the relationship between responses to appetitive cues. Utilizing both psychophysiological (startle EMG, skin conductance) and self-report measures, we compared cue reactivity to positive, neutral, aversive, smoking, and chocolate pictures among groups of 10 hr. smoking deprived smokers, non-deprived smokers, and non-smokers. Smokers responded to smoking cues similar to pleasant affect cues with more inhibited startle and high arousal, while responses from non-smoking females indicated a neutral state. However, deprivation also significantly increased startle responses to smoking cues when compared to non-deprived smokers. Furthermore, a closer look at skin conductance responses to aversive cues suggest that smoking status (deprived and non-deprived groups) significantly inhibited one?s ability to habituate to negative affect stimuli. When responses to chocolate cues were examined, psychophysiological and self-report data seemed to indicate that smoking deprivation influenced one's ability to attend to other appetitive/rewarding cues. Implications of these results on female smoking craving and sensitivity to appetitive cues are discussed.

Our laboratory has previously shown that exposure to social disruption (SDR) the week prior to Theiler’s murine encephalomyelitis virus (TMEV) infection exacerbates disease course, resulting in increased infection-related sickness behaviors, motor impairment, CNS viral titers, and CNS inflammation. These adverse effects of SDR were prevented by ICV infusion of a neutralizing antibody to IL-6 during the stress exposure period. These findings suggest that stress-induced increases in IL-6 are necessary to exacerbate acute TMEV infection, but the exact mechanism remains unknown. This thesis tested the hypotheses that SDR up-regulates central cytokine expression, exacerbates TMEV infection through cross-sensitization of virus-induced cytokine expression, and that social rank modulates the effect of SDR. In Experiment 1, Balb/cJ mice underwent the 0, 1, or 6 SDR sessions and were then sacrificed 0, 2, or 12 hours post SDR. Experiment 2 subjects received ICV infusions of either IL-6 neutralizing antibody or its vehicle before each of six 2 h SDR sessions or the control condition, the week prior to infection. In Experiment 3 mice were tested for pre-existing social rank prior to SDR and infection. Results indicate that (1) SDR increases virus-induced IL-6, IL-1B, and CD11b mRNA expression in brain,that these SDR-induced increases and acute TMEV exacerbation are prevented by ICV infusion of the IL-6 neutralizing antibody during the stress exposure period, and that (2) social rank does not modulate affects of SDR but baseline anxiety does. These findings suggest that SDR exacerbates acute TMEV infection through cross-sensitization of virus-induced cytokine expression and that baseline anxiety is a significant modulator of SDR.

This study evaluated self-monitoring and feedback procedures with preschool teachers and reactivity that occurred in a preschool classroom due to a supervisors' presence. Preschool teachers' positive interactions following the implementation of a self-monitoring and feedback procedure only slightly increased without the presence of a supervisor. Reactivity was identified with the presence of the supervisor as accurate reporting increased most in the supervisor's presence. Following the identification of reactivity, positive interactions remained at high levels during the reactivity control and maintenance conditions.

Geopolymer cements present a unique opportunity to make concrete binders almost entirely out of waste stream materials. Geopolymers made from fly ash, a waste product of coal power generation, as the aluminosilicate source and caustic activating solution were the focus of this study. However, the use of waste stream materials presents many challenges. One major stumbling block is that fly ash is inherently variable in composition and difficult to comprehensively characterize. The purpose of this work was to clarify the relationship between fly ash composition and reactivity in geopolymer cements. Ten fly ashes comprising a wide compositional spectrum were selected for the study and were characterized using quantitative x-ray diffraction and multispectral image analysis (MSIA) of x-ray maps coupled with point compositional analysis. The fly ashes were mixed into geopolymer mortars to determine their reactivity when activated as geopolymers. I hypothesized that the fly ashes that performed well under geopolymer formation conditions would have similarities in the glassy phases identified in them. The fly ashes that resulted in geopolymers with high compressive strengths did have several glassy phases in common. The phases were typically high in calcium, high in silicon, and somewhat low in aluminum. To determine whether the common phases were soluble and therefore likely to be dissolved, a dissolution method was used in which fly ash was mixed with concentrated caustic solution and continuously agitated; after 7 d and 28 d, the solid residues from the dissolution were studied using MSIA. The results showed that most of the glassy phases hypothesized to react were reactive, although the results were somewhat complex due to the heterogeneity of fly ash. The MSIA method proposed in previous work was further developed through this study, and a new way of selecting the training classes for phase composition assignment in the images was proposed. / text

The purpose of this study was to evaluate feedback systems for improving staff adherence to a toileting program at an intermediate care facility for individuals with developmental disabilities. The facility uses interoffice memos in order to provide their staff with feedback. Following baseline, we evaluated the effectiveness of the memo (B), memo plus in-service (C), and memo plus feedback (D) in an ABCDBD reversal design across 4 residences. The results showed that memo plus feedback was the most effective intervention.

Consistent with classical conditioning theories of drug use, previous research has demonstrated that presenting smokers with either exteroceptive (e.g., pictures of cigarettes) or interoceptive (e.g., negative affect) cues results in increased motivation to smoke, as measured by urge and smoking topography (e.g., shorter latency to begin smoking). However, few studies have presented both types of cues to determine whether and how they might interact in the production of smoking motivation, and little research has focused on identifying potential moderators of cue reactivity. In a randomized 2 x 2 crossed factorial between-subjects design, the current study tested whether an interoceptive cue (anxiety induced via a speech preparation task) and an exteroceptive cue (exposure to a lit cigarette) interacted in the production of urge and behavioral reactivity and whether the personality trait of impulsivity moderated these effects. Results indicated main effects but no interactive effects for the two cue types on self-reported urge, no main or interactive effects on smoking topography, and no moderating effects of impulsivity. However, impulsivity was significantly correlated with urge to smoke, self-reported negative affect, and expectancies that smoking relieves negative affect, suggesting that this trait plays an important role in continued tobacco use. Implications for future research on the relationship between impulsivity and smoking behavior are discussed.

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published_or_final_version / Chemistry / Master / Master of Philosophy