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2012

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Knn-R: Building Secure And Efficient Outsourced Knn Query Service With The Rasp Encryption, Huiqi Xu Jan 2012

Knn-R: Building Secure And Efficient Outsourced Knn Query Service With The Rasp Encryption, Huiqi Xu

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With the wide deployment of public cloud computing infrastructures, outsourcing database services to the cloud has become an appealing solution to save operating expense. However, some databases might be so sensitive or precious that the data owner does not want to move to the cloud unless the security is guaranteed. On the other hand, a secure outsourced service should still provide efficient query processing and significantly reduce the inhouse workload to fully realize the benefits of outsourcing. We summarize these key features for an outsourced service as the CPEL criteria: data Confidentiality, query Privacy, Efficient query processing, and Low inhouse …


Effects Of Elevated Glucocorticoid Levels On Dentate Gyrus Development, Zachary Dale Vallandingham Jan 2012

Effects Of Elevated Glucocorticoid Levels On Dentate Gyrus Development, Zachary Dale Vallandingham

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Exogenous glucocorticoids are commonly used in modern medications and animal studies examining the effects of glucocorticoids on the developing brain report inconsistent results. Recent reports have questioned the reliability of available drug delivery methods in mice (Herrmann et al., 2009). In our laboratory, variable behavioral results using trace eyeblink conditioning (EBC) suggest that we may be having similar problems delivering glucoroticoids to developing rat pups (Claflin et al., 2005, 2011). Subcutaneous pellets and osmotic minipumps resulted in impaired learning during trace eyeblink conditioning whereas subcutaneous injection of corticosterone (CORT) resulted in facilitation of learning on the same task. One of …


Relationship Between Log Permeability And Fraction Of Finer Grains In Bimodal Sediment Mixtures, Steven M. Verdibello Jan 2012

Relationship Between Log Permeability And Fraction Of Finer Grains In Bimodal Sediment Mixtures, Steven M. Verdibello

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In sediment mixtures of two grain-size components, the mixture porosity (Φ) and permeability (k) both vary non-linearly as a function of the grain size and the volume fraction of each component. A porosity minimum (Φmin) occurs near the mixture fraction at which the volume of the finer grains equals the original pore volume of the coarser grains. An abrupt change in slope has been observed in the non-linear relationship between log(k) and the volume fraction of finer grains (rf). This slope change should occur at the rf where coarser pore pathways change from continuous to discontinuous. In this study, fine …


Direct Optimization Of Ranking Measures For Learning To Rank Models, Li Li Guo Jan 2012

Direct Optimization Of Ranking Measures For Learning To Rank Models, Li Li Guo

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The main challenge in learning-to-rank for information retrieval is the difficulty to di- rectly optimize ranking measures to automatically construct a ranking model from training data. It is mainly due to the fact that the ranking measures are determined by the order of ranked documents rather than the specific values of ranking model scores, thus they are non-convex, nondifferentiable and discontinuous. To address this issue, listwise approaches have been proposed where loss functions are defined either by exploiting a probabilistic model or by optimizing upper bounds or smoothed approximations of ranking measures. Even though very promising results have been achieved, …


A Geophysical Investigation Searching For Archaeological Features At Sunwatch Indian Village, Danielle Torridi Jan 2012

A Geophysical Investigation Searching For Archaeological Features At Sunwatch Indian Village, Danielle Torridi

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A near-surface geophysical survey was conducted at SunWatch Indian Village in Dayton, Ohio. The main motivations for this investigation were to evaluate geophysical methods to locate, map, and identify features associated with the SunWatch Indian Village archaeological site and to expand the area surveyed. Previous studies (Houston, 2002; Miller, 2004) have determined that burials covered with limestone slabs are relatively easy to detect and map geophysically with GPR and electrical resistivity. This was reconfirmed in this study by collecting 3D GPR data over a 'control' location previously surveyed by Houston (2002) and Miller (2004). However, similar anomalies were not observed …


The Influence Of Streambed Heterogeneity On Hyporheic Exchange In Gravelly Rivers, Yaoquan Zhou Jan 2012

The Influence Of Streambed Heterogeneity On Hyporheic Exchange In Gravelly Rivers, Yaoquan Zhou

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Hyporheic exchange can be influenced by channel meanders, by streambed topography, and by the heterogeneity within subsurface sediments. Fluvial systems with streambed sediments composed of sandy gravel can be heterogeneous and contain open-framework gravel stratasets that comprise roughly one-third of the sedimentary deposit by volume. The open-framework gravel stratasets have an average lateral length scale on the order of 10 m, average thickness on the order of a decimeter, and an average dip on the order of 10 degrees downstream. The hydraulic conductivity of open-framework gravel stratasets is on the order of 10-1 m/s, and for the larger volume of …


Evaluating The Effect Of Hyporheic Exchange On Intake Temperatures Of Open-Loop Geothermal Wells In Glacigenic Outwash Aquifers, Nathan Grigsby Jan 2012

Evaluating The Effect Of Hyporheic Exchange On Intake Temperatures Of Open-Loop Geothermal Wells In Glacigenic Outwash Aquifers, Nathan Grigsby

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Subsurface heat flow was simulated to study the effect of hyporheic exchange on groundwater intake temperatures of open-loop geothermal wells in glacigenic-outwash aquifers in the North American midcontinent. The model represents an aquifer kilometers wide, on the order of 100m thick, and directly connected to a perennial river. The aquifer has bimodal hydraulic conductivity with a geometric mean on the order of 100m/day, an effective thermal conductivity of 2.33W/mK, and specific heats on the order of 106J/(m^3 K) for water and 103J/kgK for solids. The aquifer is initially set to a temperature of 12.85 °C and the river is fixed …


Cometabolic Degradation Of Halogenated Aliphatic Hydrocarbons By Aerobic Microorganisms Naturally Associated With Wetland Plant Roots, Madelyn M. Smith Jan 2012

Cometabolic Degradation Of Halogenated Aliphatic Hydrocarbons By Aerobic Microorganisms Naturally Associated With Wetland Plant Roots, Madelyn M. Smith

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Wetland systems provide both anaerobic (reducing) and aerobic (oxidizing) zones for the biodegradation of chlorinated aliphatic hydrocarbons (CAH). In particular, wetland plant roots provide micro-oxidizing environments for methanotrophic bacteria from the presence of methane, which is produced in anaerobic zones, and oxygen, which is brought to the subsurface by roots of wetland plants; this shows the potential for cometabolic degradation of common organic pollutants.

This study explored the natural attenuation of CAHs by methanotrophic bacteria naturally associated with roots of the common wetland plant, Carex comosa. Root microcosms were amended with varying concentrations of methane; trichloroethene; cis 1,2-dichloroethene; 1,2-dichloroethane; or …


Effect Of Cooling Rate And Mold Counter Pressure On The Crystallinity And Foaming Control In Microcellular Injection Molded Polypropylene Parts, Jeffrey Scott Cousineau Jan 2012

Effect Of Cooling Rate And Mold Counter Pressure On The Crystallinity And Foaming Control In Microcellular Injection Molded Polypropylene Parts, Jeffrey Scott Cousineau

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Microcellular polymer injection molding is a growing industry technique due to its ability to produce dimensionally stable stress free parts while reducing cycle time, material usage, and energy costs. The process was invented by Dr. Nam P. Suh at the Massachusetts Institute of Technology in the early 1980's. The basic idea is to dissolve a supercritical fluid into the polymer melt which will nucleate and expand within the part core after injection during the cooling stage. Microcellular polymer injection molding is becoming increasingly popular in automotive, semiconductor, and industrial applications. While the technique has been widely successful using amorphous polymers, …


Poly(Arylene) Ethers Prepared From Functionalized 3,5-Difluorotriphenylphosphine Oxide, Courtney M. Sutherland Jan 2012

Poly(Arylene) Ethers Prepared From Functionalized 3,5-Difluorotriphenylphosphine Oxide, Courtney M. Sutherland

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The di-iodinated derivative of 3,5-difluorotriphenyl phosphine oxide, 3,5-DiFTPO-I2, was synthesized for the modification of poly(arylene ether phosphine oxide)s, PAEPOs. The di-iodinated monomer was polymerized to afford the di-iodinated polymer, a pre-cursor for tailoring solubility and the thermal properties of the PAEPO derivatives via functionalization. The di-iodinated polymer was post-functionalized via the Suzuki Miyaura cross coupling reaction with a variety of boronic acids. The successful conversion of the iodo groups, along with the immense number of possible functional groups that can be introduced to the di-iodinated polymer makes PAEPO-derivative a highly useful thermoplastic with a wide range of potential uses.

The …


Mhc Class I Expression In Murine Fibroblast And Keratinocyte Cell Lines During The First Twenty-Four Hours Of Infection With Herpes Simplex Virus-1 (Hsv-1), Prasanthi Kumchala Jan 2012

Mhc Class I Expression In Murine Fibroblast And Keratinocyte Cell Lines During The First Twenty-Four Hours Of Infection With Herpes Simplex Virus-1 (Hsv-1), Prasanthi Kumchala

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The hypothesis of this study is: HSV-1 infection of murine fibroblasts and keratinocytes inhibits expression of MHC class I molecules during first 24 hours of infection. IFN-γ pretreatment of fibroblasts protected the cells from virus-induced inhibition of MHC class I expression, but did not protect keratinocytes. Herpesviruses are known for their ability to establish persistent infections. Herpesviruses exert many different ways to suppress host defense mechanisms. One such way is by down regulating expression of the major histocompatibility complex I (MHC I) molecules in infected cells. Epidermal cells such as keratinocytes are the major sites for herpes simplex virus type …


Characterization Of Ceramic Composite Materials Using Terahertz Non-Destructive Evaluation Techniques, Lindsay Owens Jan 2012

Characterization Of Ceramic Composite Materials Using Terahertz Non-Destructive Evaluation Techniques, Lindsay Owens

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The characterization of defects such as rust, voids, etc. on materials and the analysis and prediction of strain and stress induced breakdown are well known applications of non-destructive evaluation (NDE) techniques. THz radiation has been suggested as an effective NDE tool for use in the field of ceramics and ceramic matrix composite materials (CMC), via THz spectroscopy and imaging. The goal of this research is to monitor the progression of thermal and mechanical damage applied to the CMC materials using terahertz spectroscopic imaging in order to create a predictive model that will correlate THz imaging data of these materials to …


The Effects Of Hsv-1 Challenge On Polarized Murine Macrophages: An In Vitro Model Using The J774a.1 Murine Macrophage Cell Line, Adam Craig Reichard Jan 2012

The Effects Of Hsv-1 Challenge On Polarized Murine Macrophages: An In Vitro Model Using The J774a.1 Murine Macrophage Cell Line, Adam Craig Reichard

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In our current study we examined the effects of HSV-1 challenge on J774A.1 macrophages polarized to either a proinflammatory (M1) or anti-inflammatory (M2) phenotype. Polarized J774A.1 macrophages were characterized using CD14-CD86 and SOCS1-SOCS3 expression levels. SOCS proteins are a family of proteins that are capable of inhibiting cytokine-signaling pathways. HSV-1 up regulates expression of SOCS1 protein levels in infected cells, inhibiting the ability of infected cells to produce proinflammatory products (Nowoslawski Akhtar and Benveniste, 2011). This study shows that signals within the microenvironment play a greater role in macrophage polarization, and SOCS1-SOCS3 expression levels, than does HSV-1 challenge. M1 macrophages …


Linked Open Data Alignment & Querying, Prateek Jain Jan 2012

Linked Open Data Alignment & Querying, Prateek Jain

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The recent emergence of the "Linked Data" approach for publishing data represents a major step forward in realizing the original vision of a web that can "understand and satisfy the requests of people and machines to use the web content" i.e. the Semantic Web. This new approach has resulted in the Linked Open Data (LOD) Cloud, which includes more than 295 large datasets contributed by experts belonging to diverse communities such as geography, entertainment, and life sciences. However, the current interlinks between datasets in the LOD Cloud, as we will illustrate,are too shallow to realize much of the benefits promised. …


Digital Wideband Spectral Sensing Receiver, Lawrence D. Burich Jan 2012

Digital Wideband Spectral Sensing Receiver, Lawrence D. Burich

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Detecting, channelizing, and characterizing radio frequency signals is a fundamental requirement for electronic warfare receivers as well as in commercial wireless applications where it is important to determine activity/inactivity in specified bands for spectral sharing and interference avoidance. Spectral sensing receivers are required to cover bandwidths in the GHz range and channelize signals into frequency bins in the kilo-hertz or mega-hertz range depending on the application. The difficulty is to detect, then determine spectral characteristics of multiple signals with varying power levels and signal characteristics in real time. A number of current Digital Wideband Spectral Sensing Receiver (DWSSR) architectures are …


Integrity Monitoring Techniques For Vision Navigation Systems, Nicholas Allen Baine Jan 2012

Integrity Monitoring Techniques For Vision Navigation Systems, Nicholas Allen Baine

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In aviation applications, navigation integrity is paramount. Integrity of GPS systems is well established with set standards. Vision based navigation systems have been found to be an adequate substitute for GPS, when it is unavailable but are unlikely to be utilized until there is a measure for system integrity. Work has been done to detect the effect of a single measurement pair being corrupted with a bias; however, the measurement geometry varies greatly with the environment. The environment could be sparse in visual features to track, or the environment could be rich with features. With more features, there is a …


Why Is There Such A High Concentration Of Vertebrate Remains Within A Bone-Bed Along Clapp Creek, Williamsburg County, South Carolina?, Jennifer R. Soehner Jan 2012

Why Is There Such A High Concentration Of Vertebrate Remains Within A Bone-Bed Along Clapp Creek, Williamsburg County, South Carolina?, Jennifer R. Soehner

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A phosphatic bone-bed occurs along Clapp Creek in Kingstree, South Carolina, within the east-central portion of the coastal plain. The location of the research site is within the Chicora Member of the Williamsburg Formation. The paleoenvironment of this site was most likely a complex estuary with microenvironments that included tidal channels, tidal deltas, tidal flats, marshes and subtidal bays. The high diversity and large time span in the bone-bed is explained by the transgressive environment and storm deposits. The phosphate content of the bone-bed is from the calcium phosphate occurring in the coprolites of carnivores and the higher concentration of …


Computational Investigations Of The Adsorption Of Molecular Hydrogen On Graphene-Based Nanopore Model, Jared Duncan Jan 2012

Computational Investigations Of The Adsorption Of Molecular Hydrogen On Graphene-Based Nanopore Model, Jared Duncan

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Computational modeling using classical grand canonical Monte Carlo simulations and first-principles calculations were carried out to study the adsorption of molecular hydrogen on nanoporous carbon modeled by the slit- pore geometry. It has previously been shown that hydrogen adsorption on pristine porous carbon has dependence on pore size and that an optimum pore size, which exhibits the maximum mass uptake, exists. There have been suggestions that doping graphitic nanocarbon structures with Pd enhances their adsorption capacity. The pore-size dependence of this change in adsorption brought about by Pd and the conditions at which improvement in adsorption can occur have not …


Enhancing Description Logics For Rules Coverage, David Carral Martinez Jan 2012

Enhancing Description Logics For Rules Coverage, David Carral Martinez

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This thesis is a formal study on how to extend the set of logic constructors of description logics languages, used for knowledge representation in the Semantic Web field to capture some of the previously exclusive rules expressivity. Description Logics, the logics underpinning the Web Ontology Language OWL, and rules are currently the most prominent paradigms used for modeling knowledge for the Semantic Web. While both of these approaches are based on classical logic, the paradigms also differ significantly, so that naive combinations result in undesirable properties such as undecidability. Recent work has shown that many rules can in fact be …


Turbine Base Pressure Active Control Through Trailing Edge Blowing, Bayindir Huseyin Saracoglu Jan 2012

Turbine Base Pressure Active Control Through Trailing Edge Blowing, Bayindir Huseyin Saracoglu

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The desire for high performance and low fuel consumption aero-engines has been pushing the limits of the turbomachinery and leading cutting-edge engine designs to fulfill the demand. The number of stages is reduced to achieve the same pressure ratios over lighter turbines. The extreme expansion requirements result in transonic-supersonic flow fields. Transonic and supersonic turbines are exposed to the shock waves that appear at the trailing edge of the airfoils, generating substantial efficiency deduction due to the interaction with the boundary layer. Furthermore, pressure fluctuations created by the shocks result in unsteady forcing on downstream components and eventually cause high …


A Hardware Compact Genetic Algorithm For Hover Improvement In An Insect-Scale Flapping-Wing Micro Air Vehicle, Kathleen M. Timmerman Jan 2012

A Hardware Compact Genetic Algorithm For Hover Improvement In An Insect-Scale Flapping-Wing Micro Air Vehicle, Kathleen M. Timmerman

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Wing and airframe damage to insect scale micro air vehicles potentially cause significant losses in pose and position control precision. Although one can imagine many possible means of adapting the flight controllers to restore precise pose and position control, severe limits on computational resources available on-board an insect sized vehicle render many of them impractical. Additionally, limits on sensory capability degrade any such vehicle's ability to critique its own performance. Any adaptive solutions one would propose to recover flight trajectory precision, therefore, would require a resource light implementation, preferably without need for relatively expensive floating-point operations, along with the capability …


Prediction Of Optimal Bayesian Classification Performance For Ladar Atr, Kristjan H. Greenewald Jan 2012

Prediction Of Optimal Bayesian Classification Performance For Ladar Atr, Kristjan H. Greenewald

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We consider the problem of LADAR ATR classifier performance prediction in the presence of arbitrary nuisance parameters including but not limited to pose. We use several noise models for both range images and point clouds that are significantly more accurate and complex than the Gaussian models used by previous non-Monte Carlo prediction methods. Two accurate new methods of efficiently predicting the optimum Bayesian classification performance are then derived, and applied to the noise models. Advantages of these methods include significant gains in accuracy for medium to high noise levels and the ability to handle target near symmetry. Extensions are developed …


Terahertz Time Domain Spectroscopy And Fresnel Coefficient Based Predictive Model, Justin C. Wheatcroft Jan 2012

Terahertz Time Domain Spectroscopy And Fresnel Coefficient Based Predictive Model, Justin C. Wheatcroft

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An optical material parameter predictive model that accounts for sample to air interfaces was developed. The model predicts how a terahertz time-domain spectroscopy time domain pulse will be affected as it passes through a given thickness of a material. The model assumes a homogenous, linear, isotropic dielectric or semiconductor. The inputs to the model are the real and imaginary refractive indices across the desired frequency band. Different dielectric material's optical parameters were taken from the literature and the predicted time domain pulses were shown. It was also shown that the refractive index and absorption coefficient for samples that were optically …


Modeling The Exfoliation Rate Of Graphene Nanoplatelet Production And Application For Hydrogen Storage, Cory Knick Jan 2012

Modeling The Exfoliation Rate Of Graphene Nanoplatelet Production And Application For Hydrogen Storage, Cory Knick

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Graphene is a unique and revolutionary new nanomaterial. A method for it's production had a U.S. patent application in 2002 (patent issued in 2006), it was produced via mechanical exfolia-tion in 2004, and subsequently the Nobel Prize in Physics was awarded in 2010 for it. These events have sparked a surge of graphene-related research. In order for graphene to be widely studied and incorporated into emerging technologies, a versatile method for large scale produc-tion of high-quality graphene is required. Current methods are either slow or expensive which limits the scale-up of graphene production. Very recently, the liquid phase exfoliation of …


Computational Study On Micro-Pilot Flame Ignition Strategy For A Direct Injection Stratified Charge Rotary Engine, Zachary Steven Votaw Jan 2012

Computational Study On Micro-Pilot Flame Ignition Strategy For A Direct Injection Stratified Charge Rotary Engine, Zachary Steven Votaw

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The Office of Security of Defense's Assured Fuels Initiative has recently been pressing for a single fuel battle space. This endeavor requires modifying many of the vehicle power plants currently in operation throughout the Armed Forces. The RQ-7 Shadow, an unmanned aerial vehicle (UAV) utilized by the Marine Corp and Army for reconnaissance purposes, is powered by UEL's AR741 rotary engine and functions on aviation fuel. One effort underway has been focused on developing this rotary engine system to operate on heavy fuels using direct injection technology and charge stratification. Although the rotary engine has many advantages over standard reciprocating …


Suppressor Of Cytokine Signaling (Socs) 1 & 3 Expression In Hsv-1- Infected And Interferon-Γ-Treated Neuro-2a Cells, Melinda Jones Jan 2012

Suppressor Of Cytokine Signaling (Socs) 1 & 3 Expression In Hsv-1- Infected And Interferon-Γ-Treated Neuro-2a Cells, Melinda Jones

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This study examined the effects of HSV-1 infection and IFN-γ treatment on Neuro-2A cells. HSV-1 induces expression of SOCS1 and SOCS3 in infected cells, inhibiting the ability of these cells to produce the pro inflammatory, antiviral cytokine IFN-γ (Nowoslawski and Benveniste, 2011). SOCS1 and SOCS3 levels were determined in IFN-γ-treated cells, virus-infected cells, and cells that were both IFN-γ-treated and virus-infected. Results were compared with untreated, uninfected control cells. Flow cytometry data analysis showed a slight decrease in SOCS1 and SOCS3 protein levels in cells treated with IFN-γ for 6 hours compared to control cells. A significant decrease in SOCS1 …


System Optimization And Patient Translational Motion Correction For Reduction Of Artifacts In A Fan-Beam Ct Scanner, Zachary Gordon Lee Wise Jan 2012

System Optimization And Patient Translational Motion Correction For Reduction Of Artifacts In A Fan-Beam Ct Scanner, Zachary Gordon Lee Wise

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In computed tomography (CT) systems, many different artifacts may be present in the reconstructed image. These artifacts can greatly reduce image quality. For our laboratory prototype CT system, a fan-beam/cone-beam focal high-resolution computed tomography (fHRCT) scanner, the major artifacts that affect image quality are distortions due to errors in the reconstruction algorithm's geometric parameters, ring artifacts caused by uncalibrated detectors, cupping and streaking created by beam hardening, and patient-based motion artifacts. Optimization of the system was required to reduce the effects of the first three artifact types, and an algorithm for correction of translational motion was developed for the last. …


Phosphorus Mass Balance For Hypertrophic Grand Lake St. Marys, Ohio, Astrea Taylor Jan 2012

Phosphorus Mass Balance For Hypertrophic Grand Lake St. Marys, Ohio, Astrea Taylor

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A phosphorus (P) budget was created for Grand Lake St Marys (GLSM), a hypertrophic lake in Ohio with a highly agricultural watershed. Inputs totaled 71,200 ± 8,400 kg P, with tributaries contributing the majority of P inputs at 60,100 ± 4,500 kg P (84%). Other inputs included benthic flux at 9% (internal loading), point-source discharges into streams at 5%, and atmospheric deposition at 1%. Rainfall in 2011 was greater than average, which may affect results when comparing this P budget to years with average rainfall. Transport of P by two rivers draining GLSM was approximately three times greater than benthic …


Central Arctic Lithostratigraphy: Implication For Sediment Transport And Paleoceanography, Edward Augustus Council Iii Jan 2012

Central Arctic Lithostratigraphy: Implication For Sediment Transport And Paleoceanography, Edward Augustus Council Iii

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Multiple cores from the Arctic were analyzed by XRF methods to determine the western Arctic lithostratigraphy as expressed in its geochemistry. In general, glacial and interglacial events have distinctly different chemistry. During glacial events, the sediments have elevated Ti, Fe, Rb, and Zr concentrations and depressed Sr and Mn concentrations. The opposite is true of the brown layers, where Ti, Fe, Rb and Zr are lower with higher levels of Mn and Sr. These data indicate that there are 18 chemically unique lithologic units (LUs) that exist among MIS-1 to MIS-16 age sediments. Isopach maps indicate two general depositional patterns …


Synthesis Of Mixed Metal Trinuclear Cluster Of Molybdenum And Tungsten And Their Electrochemistry In Ionic Liquids, Jessica Ann Davis Jan 2012

Synthesis Of Mixed Metal Trinuclear Cluster Of Molybdenum And Tungsten And Their Electrochemistry In Ionic Liquids, Jessica Ann Davis

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Research is being done to find a material to improve the efficiency of the ethanol fuel cell by using a platinum free catalyst. Mo2WO2(O2CCH3)6 cluster was synthesized using Mo2(O2CCH3)4 dimer and Na2WO4. One ionic liquid, EMImBF4, was synthesized using methylimidazolim and chloroethane in the first step, and EMImCl and NaBF4 in the second step. The electrochemical properties of the ionic liquid and the metal cluster were studied. A potential window for the EMImBF4 was found to be 3.2 V. The ionic liquid has a wider potential window, and allowed for the observation of the redox properties of Mo2WO2(O2CCH3)6. The electrochemistry …