The energetics of cast calcium sulfate dihydrate-aluminium thermites was explored and its use as a potential metal-cutting tool was investigated. Thermite is a pyrotechnic composition that undergoes a highly exothermic reaction that burns relatively slowly. It is often used in cutting, welding and incendiary devices. Consolidation of thermite by casting was chosen to enable control of the burning front. The base case thermite comprised 60 wt-% calcium sulfate dihydrate oxidiser and 40 wt-% aluminium fuel. Addition of additives were considered for their effect on the cast thermite’s setting time, density, surface temperature, reaction products and burn rate. EKVI and FactSage thermodynamic simulations were used to determine optimum compositions for the various systems. The thermite powder compositions were sieved before mixing with water and casting in a mould. The casts were allowed to set for 3 days to form calcium sulfate dihydrate-aluminium compositions. The copper sulfate pentahydrate additive was found to significantly decrease the setting time of the casts. The heat of hydration of the base case was 59 ± 8 J g−1 . The compressive strength reached 2.9 ± 0.2 MPa, the open air burn rate was 12.0 ± 1.6 mm s −1 and a maximum surface temperature of 1370 ± 64 °C was recorded using a pyrometer. Bomb calorimetry indicated an energy output of 7.96 ± 1.07 MJ kg−1 , slightly lower than predicted by the EKVI simulation. The density of the castings was varied by either adding hollow sodium borosilicate glass spheres or by adding excess water. The glass spheres resulted in a burn rate that decreased nonlinearly with decreasing cast density. The excess water made no changes to the burning, except for increasing the burn rate of the copper sulfate pentahydrate-based thermite. Calcium sulfate in the casts was also dehydrated by thermal treatments at 155 °C and 200 °C. This resulted in significant increases in the burn rate due to the porosity created by the evaporation of the hydration waters. Castings that were thermally treated in an oven at 155 °C were successful in puncturing part of an aluminium block in confined burn tests. A hole with a diameter of ~13.6 mm and depth of ~7 mm was produced. It is recommended that the composition with copper sulfate pentahydrate be used as a binder in further tests. / Dissertation (MEng)--University of Pretoria, 2018. / Chemical Engineering / MEng / Unrestricted

This study investigated the impact of a psychoeducational and experiential structured counselor self-care curriculum, developed by Drs. Charles and Kathleen Figley, on compassion fatigue and the prevention of professional impairment as measured by the Professional Quality of Life (ProQOL), Version 5. Volunteer licensed professional counselors, supervisors, and interns from four children's advocacy centers in Texas were assigned to treatment group (n = 21; 20 females, 1 male; mean age 34.4 years) or waitlist control group (n = 21; 19 females, 2 males; mean age 34.6 years). Participating counselors identified themselves ethnically as 64% Caucasian, 26% Hispanic, 7% African-American, and 2% Native-American. Employing a quasi-experimental design, three reliability-corrected analysis of covariance (ANCOVA) were utilized to analyze the data with an alpha level of .05 to assess statistical significance and partial eta squared to assess effect size. With pre-test scores as the covariate, results revealed in the experimental group a statistically significant reduction with large treatment effect for burnout (p = .01; partial ?2 = .15), a statistically nonsignificant reduction with a medium effect for secondary traumatic stress (p = .18; partial ?2 = .05), and a statistically nonsignificant increase with a medium effect for compassion satisfaction (p = .06; partial ?2= .09). Findings supported the use of this curriculum to train counselors on self-care as required of professional counselors by the American Counseling Association code of ethics and listed as a necessary skill in the standards of the Council for Accreditation of Counseling and Related Educational Programs.

The relationship between occupational stress and burnout was investigated through a meta-analysis of 81 studies and 364 correlations. Occupational stress was measured by role conflict, role ambiguity, workload, cumulative role stress, job specific stress/stressors, and work setting characteristics. Burnout was measured by the Maslach Burnout Inventory, 1981 and 1986 versions, emotional exhaustion, depersonalization, and reduced personal accomplishment components of burnout, measures of tedium, and the Staff Burnout Scale for Health Professionals. Thirty occupations in human and non-human service organizations throughout four publication periods were examined. Results indicated occupational stress strongly predicts burnout in non-human service organizations like industry and manufacturing as well as the human services. Job specific stressors most strongly predict burnout across organization types and occupation. Occupational stress predicts emotional exhaustion and depersonalization more than perceptions of reduced personal accomplishment. The findings support the use of transactional models of stress which consider occupational context as a precipitator of burnout, especially emotional exhaustion.

Portugal is one of the Mediterranean countries that besides its natural condition to occur forest fires, has had an increase of forest fires during the last decades and has a consequence the increase of the burned surface and the costs associated, economic, social and environmental. This study case took place in Serra da Freita, a mountain region in the north of Portugal in the Aveiro District. The aim of this case study was to establish a relation between forest fires, erosion and social consequences for the region. For this purpose, a mixed approach was used with Remote sensing to acquire burn severity (dNBR) by comparing the areas before and after forest fires, soil analyses, and with a questionnaire to the local community to comprehend how they are affected. The results obtained permits to understand that not only the forest fires have a direct impact on the soil erosion, but also affect the local community by promoting the abandonment of the area.

Rangelands are heterogeneous working landscapes capable of supporting livestock production and biodiversity conservation, and heterogeneity-based rangeland management balances the potentially opposing production and conservation goals in these working landscapes. Within fire-dependent ecosystems, patch-burn grazing aims to create landscape patterns analogous to pre-European rangelands. Little work has tested the efficacy of patch-burn grazing in northern US Great Plains. We investigated patch contrast in above and belowground ecosystem properties and processes during the summer grazing seasons from 2017 ? 2020 on three patch-burn pastures stocked with cow-calf pairs and three patch-burn pastures stocked with sheep. We focused on vegetation structure, plant community composition, forage nutritive value, grazer selection, livestock weight gain, soil nutrient pools, soil microbial community composition, and decomposition activity. We used mixed-effect models and ordinations to determine whether differences: along the time since fire intensity gradient, between ecological sites, and between grazer types existed. Despite no significant shifts in the plant community, structural heterogeneity increased over time as the number of time since fire patches increased and was higher than homogeneously managed grasslands. Grazing livestock preferred recently burned patches where the available forage had a higher nutritive value and lower available biomass than surrounding patches at a given point in time. With the exception of 2018, livestock weight gains were consistent. Soil nutrient pools and microbial abundances differed more by ecological site than by the time since fire intensity gradient, and ecological sites exhibited similar nutrient and microbial responses to the time since fire intensity gradient. That belowground response variables were mostly resistant to patch-burn grazing is supportive of further use of this management, especially given the desirable results with aboveground response variables.

The concept of compassion fatigue (CF) emerged in the early 1990s in North America to explain a phenomenon observed in nurses employed in emergency departments. A precursor to burnout, CF is a well-known phenomenon associated with emotional exhaustion, depersonalization, and an inability to work effectively. In nurses, CF has been shown to reduce productivity, increase staff turnover and sick days, and lead to patient dissatisfaction and risks to patient safety. The aim of this study was to determine if the use of a Watson Room designated as a 'quiet zone' with warm colors on the wall, massage chair, and soothing sounds in the workplace environment, reduced CF in clinical nurses at the bedside in acute care settings. The data came from a survey of nurses (n = 19) working in a level 1 trauma center in an acute care setting. This quantitative study was conducted over a two week period. A single-group of nurses completed both a pre and post professional quality of life (ProQol) survey, a 30 item self-measurement of positive and negative aspects of caring. The ProQol operationalizes in three subcategories: compassion satisfaction (10 items), burnout (10 items), and CF (10 items). The ProQOL survey results showed statistically significant differences in the mean scores in all three categories. Paired samples t tests indicate the Watson Room proved to be successful in increasing compassion satisfaction (p = .009), decreasing burnout (p = .002), and decreasing secondary trauma/CF respectively (p = .02). This study shows the importance of nurses taking care of themselves while taking care of others. Understanding CF and devising and implementing interventions to address the subject are important for nurses and patients.

Data were collected from 388 administrators from ten urban and suburban school districts in Oregon and Washington to identify the work values of public school administrators, (as measured by the Ohio Work Values Inventory, OWVI), and determine the relationship between public school administrator role perceptions associated with burnout, (as measured by the Administrator Role Perception Inventory, ARPI), and their work values. The data were analyzed by levels of administration, background data and specific scales on the instruments. Cluster sampling by district was used; i.e. all administrators within each of ten school districts in Oregon and Washington comprised the initial sample of 701 administrators. The independent variables of the study were level of administration and the biographical descriptors of sex, age, education, administrative work experience and years of administrative experience at the same job and at the same location. The dependent variables were the seven constructs of the ARPI and the eleven constructs of the OWVI. The results indicated only moderate burnout in administrators in the sample and no statistically significant differences in the burnout among different levels of administration, although respondents reported moderate to considerable job stress. There were no significant differences in the burnout of male and female administrators and in nine of the 11 work values measured. Women administrators assigned statistically significantly more importance to the work values of Self-realization and Ideas/Data. In total, there were 35 statistically significant correlations between the OWVI scales and the ARPI subscales and the Total ARPI scale, indicating there are statistically significant relationships between administrator work values and role perceptions associated with burnout. Statistically significant differences were found between three work values of central office administrators and elementary school administrators, with central office administrators assigning statistically significantly more importance to the work values of Independence and Prestige and less importance to Altruism than did elementary school administrators and statistically significantly more importance to Independence than building administrators. Respondents assigned the greatest importance to the work value of Task Satisfaction and the least importance to Solitude. Administrators assigned considerable importance to the work values of Altruism, Independence and Ideas/Data Orientation.

It was accidentally discovered in the 1940s that the addition of lead to double-base propellants, resulted in beneficial burn rate phenomena. However, due to its toxicity the Department of Defense has been trying to find a replacement for lead over the last decade. Research efforts with this goal in mind have generally used the same methodology of either adding different metals, using different grain sizes, or using different concentrations to obtain the same burn rate effects as lead. Although some metal oxides demonstrated significant promise, they also depleted the double-base propellant stabilizer faster than acceptable, decreasing shelf life. The research explored herein does not take the same approach, but rather attempts to replace lead and solve the stability problem at the molecular level using a novel design. The new method was to synthesize a stabilizer ligand complex with a less toxic metal to create a complex that both stabilized the propellant and provides a burn rate modifying agent. First, the synthesises of two leaded complexes, tetrakis (µ3-(4-methyl-3-nitrophenyl imido lead (II))) and bis(dinitrophenyl imido lead(II)) are reported as both a proof of concept and to determine a feasible synthetic pathway. After various unsuccessful attempts using common stabilizer molecules as ligands, n-phenylurea was identified as a suitable analogous stabilizer molecule and was bonded to a cobalt center to create hexa-1-phenylurea cobalt(II) nitrate. Additionally and serendipitously, unreported complexes of metal ions with dicyanamide were discovered, which generated a discussion between ligand strength and metal center. Each of the complexes are characterized in depth and many physical properties determined. / Chemistry

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