Physical Sciences and Mathematics Commons^™

Commercial Program Development For A Ground Loop Geothermal System: Energy Loads, Gui, Turbulent Flow, Heat Pump Model And Grid Study, Paul A. Gross Ii

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The use of the earth's thermal energy to heat and cool building space is nothing new; however, the heat transfer approximations used in modeling geothermal systems, leave uncertainty and lead to over sizing. The present work is part of a Wright State effort to improve the computer modeling tools used to simulate ground loop geothermal heating and cooling systems. The modern computer processor has equipped us with the computation speed to use a finite volume technique to solve the unsteady heat equation with hourly time steps for multi-year analyses in multiple spatial dimensions. Thus we feel there is more need …

The Kozeny-Carman Equation Considered With A Percolation Threshold, Lee Brenson Porter Ii

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A procedure has been developed for calculating permeability (k) from the Kozeny-Carmen equation, a procedure that links ideas from percolation theory with the ideas of Koltermann and Gorelick (1995) and Esselburn et al. (2011). The approach focuses on the proportion of coarser pores that are occupied by finer sediments and defines a threshold proportion. For proportions below this threshold, the unoccupied coarser pores percolate. Following the ideas of Koltermann and Gorelick (1995), the effective grain-size term in the Kozeny-Carman equation is calculated using the geometric mean if below the threshold proportion, and with the harmonic mean if above. Following ideas …

Analysis Of An Eocene Bone-Bed, Contained Within The Lower Lisbon Formation, Covington County, Alabama, Angela Ann Clayton

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A fossiliferous lag layer is exposed, at low water levels, next to Point "A" Dam north of River Falls, Alabama. The location of the research site was a coastal region, during the Middle Eocene, and most likely an estuary with complex depositional systems due to the interaction of fluvial and tidal processes. Most of the vertebrate remains at this locality are well preserved and indicate a low-energy environment. The exposure consists of unconsolidated sands rich with Chondrichthyan and Reptilian remains. Little work has been conducted at this location and the exposure was thought to be conformable. With a thorough lithological …

Marine Vertebrate Remains From Middle-Late Devonian Bone Beds At Little Hardwick Creek In Vaughns Mill, Kentucky And At The East Liberty Quarry In Logan County, Ohio, John M. James

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Stratigraphic, lithologic, faunal and condont biozone analysis will provide insight to whether or not East Liberty Bone Bed, in Logan County, Ohio, and Little Hardwick Creek Bone Bed C, in Vaughns Mill, Kentucky, are chronostratigraphic correlations to one another; they are separated by 370 kilometers (230 miles). Material from each bed was collected and broken down in acid and analyzed. Remaining residue after acid treatment was analyzed under a dissecting microscope for lithological and fossil contents, identified from previous fossil vertebrate findings at other locations.

Final analysis of these beds showed that lithologically and faunally they are very similar. However, …

Methylmercury In Mosquitoes: Impact Of A Large Coal-Fired Power Station In Central Ohio, Matthew J. Konkler

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Emissions from coal-fired utilities are the major anthropogenic source of mercury (Hg) to the atmosphere. Because emitted Hg may be deposited near the source, there are concerns on levels of toxic monomethylmercury (MeHg) in local biota. We investigated the potential impact of a large Hg-emitting (> 500 kg Hg y-1) coal-fired power station on MeHg levels in mosquitoes near the Conesville power station in central Ohio. Mosquitoes were sampled with CO2-baited traps at 23 locations within a 60 km radius of the utility and at three reference sites distant from Hg combustion sources. MeHg in mosquitoes within a 30-km radius …

Commercial Program Development For A Ground Loop Geothermal System: G-Functions, Commercial Codes And 3d Grid, Boundary And Property Extension, Kyle L. Hughes

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The rise in fossil fuel consumption and green house gas emissions has driven the need for alternative energy and energy efficiency. At the same time, ground loop heat exchangers (GLHE) have proven capable of producing large reductions in energy use while meeting peak demands. However, the initial cost of GLHEs sometimes makes this alternative energy source unattractive to the costumer. GLHE installers use commercial programs to determine the length of pipe needed for the system, which is a large fraction of the initial cost. These commercial programs use approximate methods to determine the length of pipe mainly due to their …

Littoral Zone Structure, Energy Mobilization And Benthic Food Webs In Oligotrophic Northern Temperate Lakes, Shawn P. Devlin

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Lakes are usually described by pelagic-based characteristics such as trophic status or stratification and mixing regimes. These categorization schemes neglect among-lake differences in the physical and biological structure of the littoral zone. The extensive use of stable isotopes has led to a better integration of pelagic dynamics and littoral processes in limnology. In order to further our understanding of littoral trophic dynamics I conducted a detailed investigation of benthic primary production, littoral sediment bacterial production, and zoobenthic consumer resource use in oligotrophic temperate lakes. I have found that among-lake variation in benthic primary and bacterial production reflects littoral zone structure. …

Ab Initio Simulations Of Graphene-Based Nanosensor For Detecting No2 And Li, Ahmed Jama Hassan

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Nanosensors, i.e., sensors based on nanomaterials, have the potential of superior performance owing to their size effect, and can have significant effects on detection of pollutants in the environment. Various nanowires have been used in this context. Here we investigate the possibility of NO2 and Li detection using the quantum conductance change in graphene nanoribbon. Quantum conductance modification in graphene nanoribbon upon NO2/Li adsorption was calculated using ab initio methods. The optimized structures of the adsorbed NO2 indicated two different geometries where either nitrogen or oxygen was closer to the graphene lattice. The former resulted in charge transfer from NO2 …