Pool boiling process is frequently encountered in a number of engineering applications. It is difficult to exactly predict the heat transfer coefficient. This is because the boiling phenomenon is rather complex and influenced by many factors, such as surface condition, heater size, geometry, material, arrangement of heated rods, and refrigerants, etc. The key boiling parameters (bubble dynamics data) such as bubble departure diameter, frequency, velocity and nucleation site density will be varied in such different heated surface resulting in the different effect of heat transfer. Furthermore, more fundamental of the physical phenomenon can be obtained. This study was performed experimentally. R-134a and R-600a were used as refrigerants. The surface condition will be changed with plasma spray coating. It is expected that the surface condition can affect the nucleate boiling heat transfer in certain degree. In addition, using the high speed digital vide camera and LDV to measure the bubble diameter and dynamics of R-600a and R-134a while growing. According of the results of experiments. The boiling curves in different situation were drawn and the influences of heat transfer coefficients by bubble velocity was also examinate. Finally, to broaden our basic understanding of different characteristics of refrigeration surface condition and heat transfer coefficient, thermal design data of a flooded type evaporator of high performance as well as more and further physical insight of the above-stated nucleate boiling heat transfer can be acquired. The results will hopefully be helpful not only for the academia but for the industry.

Laminated and annually-laminated sediments are found in Loe Pool. The origins of such laminations are investigated and evidence for their conditions of formation are presented. In all sediment analysed the combustion residue was greater than 80%, and in the black and grey annually-laminated sediment the organic matter was less than 3%. This indicated that the sediment was dominated by a minerogenic input. The high lacustrine sediment concentrations of copper, zinc and other heavy metals together with evidence from analysis of magnetic variables which indicated high levels of haematite, confirmed that a major sediment source was effluent from mine waste. Analysis of individual black and grey annual laminations revealed increased concentrations of chlorophyll c, phaeopigments and perylene together with a lower C: N ratio in the black lamination. This indicated formation of the black layer in the summer months. From the high iron: manganese ratio and the low concentrations of calcium and carbonate in the black lamination as compared with the grey layer it was apparent that the black lamination was formed under conditions of oxygen shortage, and the grey lamination was formed when the bottom waters were fully oxygenated. It was concluded that from the analysis of selected physical and chemical properties of individual laminations it was possible to identify the principal sediment source, the likely season of deposition of each lamination and the palaeo-redox condition of the lake at that time. From this information a hypothesis of the formation of the laminated sediments in Loe Pool is proposed. It is suggested that a dominant factor controlling sediment composition was the redox conditions at the time of deposition. These conditions were primarily influenced by lake depth, lake mixing, input of allochthonous material and the oxygen demand of sedimenting material.

This report describes the processes, working habits, materials, and multiple iterations of my work over the past three years. I reflect more in depth on my final series of work in which I have incorporated images of empty pool structures into paintings and large drawings. I consider the pool images metaphors for containment, control of the landscape, the unknowable, and in both a material and psychological sense, the void. The objects I exhibit, drawings, paintings and prints, are generated using a convoluted process. Rather than working in a systematic way, I negotiate rapid impulses, subjective goals, and thematic consistency. When I use figure/ground reversal and gestural drawing, I look to create a hand-touched surface that generates a sense of uneasiness in the composition, and a subjective disruption in the landscape. / text

The species pool for a site is defined as that set of species which have a non-zero probability of maintaining viable populations under the prevailing environmental conditions. it may contain many more species than are actually present in the community of the site. The science of community assembly attempts to understand how particular communities arise from the welter of possible species combinations. The assembly of a grassland plant community from the local species pool was examined in a phylogenetically corrected trait-based study. Competition theory suggests coexisting species should be less similar than expected by chance, whilst environmental sorting theory suggests they should be more similar. This work suggests that, at the whole community scale, species tend to be more similar and that their likelihood of occurrence in communities can to an extent be predicted from their traits. Experimental studies revealed a complicated picture. Species naturally occurring in the community did not show convincing signs of outperforming their absent congeners. Community composition appears to depend in considerable measure upon chance events such as seed dispersal coinciding with the availability of vacant microsites in the community, rather than just a sorting process in which the best suited species are invariably present. These findings suggest that it modelling community assembly is possible, but that it is unlikely ever to be an exact science because it is influenced to a large extent by unpredictable events.

Graduation date: 2006

Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 73-78).

Although sand deposits are present on many intertidal rocky shores, their effects on species richness, zonation and trophic structure have often been overlooked. This study is the first to recognise sand as an important abiotic factor on South African rocky shores. Rocky shores in the eastern Cape Province of South Africa are subject to extensive sand inundation and are composed of two hard substrata of differing topographies. Four sites on one substratum and six on the other were sampled quantitatively using quadrats. The biota were identified, counted and/ or weighed to provide a matrix of species biomass and numbers in separate zones. This matrix was then analysed using ordination and classification. A total of 321 species were identified which is more than local rocky or sandy shores. While the intermediate disturbance hypothesis would predict high species richness on these shores, it does not fully explain this richness nor the distribution of species assemblages. Habitat heterogeneity, including the dynamics of sand deposits, is strongly influenced by substratum topography and is the most important factor generating species richness. Abrasion by sand (sand scour) causes local reductions in richness but the presence of semi-permanent sand deposits allows habitation by psammophilic and sand-dependent species. As a result the biota of a sand inundated rocky shore includes both a full rocky shore and a large sandy beach component. Substratum topography controls patterns of sand deposition and retention and community analysis showed that samples were clustered primarily according to species richness and secondarily according to substratum type. Ordination of species identified an arc of species assemblages of decreasing levels of sand tolerance. These corresponded to sample groupings so that th assemblages found in various habitats were characterised by particular levels of sand tolerance. The presence of sand has a negative effect on the biomass of primary producers and filter feeders but a positive effect on the biomass of deposit feeders. Because sand is retained to different degrees in different zones, trophic structure varies between zones and to a lesser extent, between rock types. In general, however, the trophic structure of sand inundated rocky shores is similar to that of non-inundated shores.

Temporary wetlands are important breeding sites for herpetofauna, including species of concern, but are often overlooked in conservation planning and management decisions. I conducted surveys of herpetofauna communities and quantified habitat variables surrounding isolated, upland and stream-connected ephemeral pools on Tombigbee National Forest and Noxubee National Wildlife Refuge in north-central Mississippi from March 2004 ? March 2006 to compare herpetile species assemblages between different classes of temporary wetlands, determine use of pools as reproductive sites for amphibians, and determine faunal-habitat relationships for herpetofauna. Species richness and abundance of terrestrial herpetiles differed significantly between upland and floodplain pools. Upland pools contributed substantially more to the diversity of herpetiles than floodplain pools. Upland pools supported significantly greater abundance of larval Ambystomatid salamanders and central newts (larvae and adults). Forest overstory and ground coverage components influenced amphibian abundance such as abundance of mature trees, standing snags, downed woody debris, and litter depth.

As the body moves through space ephemeral lines of movement are created. These lines of movement are influenced by body tendencies. We learn from the body by watching the path and patterning of movement. From the study of the movement of the body, theories of spacial movement were developed. The goal of my project is to draw from spacial movement theory to create an architectural expression that motivates movement of the body on my site and through my building. The focus of my thesis is the movement theory of Rudolph Laban (1879-1958), a modern dance pioneer and a spacial movement theorist. / Master of Architecture

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