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Evaluation Of First Order Error Induced By Conservative-Tracer Temperature Approximation For Mixing In Karstic Flow, Philippe Machetel, David A. Yuen 2015 Geosciences Montpellier CNRS/UM2/UMR5243

Evaluation Of First Order Error Induced By Conservative-Tracer Temperature Approximation For Mixing In Karstic Flow, Philippe Machetel, David A. Yuen

Sinkhole Conference 2015

Fluid dynamics in karst systems is complex due to the heterogeneity of hydraulic networks that combine the Porous Fractured Matrix (PFM) and the interconnected drains (CS). These complex dynamic systems often need to be treated as “black boxes” in which only input and output properties are known. In this work, we propose to assess the first-order error induced by considering the temperature as a conservative tracer for flows mixing in karst (fluvio-karst). The fluvio-karstic system is treated as an open thermodynamic system (OTS), which exchanges water and heat with its surrounding. We propose to use a cylindrical PFM drained by …


Numerical Simulation Of Karst Soil Cave Evolution, Long Jia, Yan Meng, Zhende Guan, Lipeng Liu 2015 Institute of Karst Geology and Key Laboratory of Karst Collapse Prevention

Numerical Simulation Of Karst Soil Cave Evolution, Long Jia, Yan Meng, Zhende Guan, Lipeng Liu

Sinkhole Conference 2015

This study is focused on numerical simulation of the formation and development of karst soil caves related to cover-collapse sinkholes. The so-called ‘karst soil cave’ refers to the caves formed in the soil layers above bedrock of sinkhole regions. Because the soil caves are formed and developed under groundwater seepage, studying groundwater level changes can help understand soil cave development and collapse. Based on the improved Terzaghi loosening pressure theory and using excess pore water pressure, two kinds of critical groundwater level decline are discussed. The first, denoted as ∆H0, is the critical groundwater level decline related to soil cave …


Building Codes To Minimize Cover Collapses In Sinkhole-Prone Areas, George Veni, Connie Campbell Brashear, Andrew Glasbrenner 2015 National Cave and Karst Research Institute

Building Codes To Minimize Cover Collapses In Sinkhole-Prone Areas, George Veni, Connie Campbell Brashear, Andrew Glasbrenner

Sinkhole Conference 2015

Cover- collapse sinkholes are forming with increasing frequency under buildings. Analyses of sinkhole distribution in Beacon Woods, Florida, preliminarily indicate their occurrence is an order of magnitude greater in urban versus undeveloped areas, suggesting the structures themselves are enhancing the collapse process. The most likely causes are induced recharge via at least one of two sources. First, runoff and drainage from roads, structures, and impoundments that is not adequately dispersed will promote sinkhole development. Second, leaking water, sewer, and septic systems beneath or adjacent to a structure will also promote collapse. The process of cover-collapse from induced recharge is well …


Hazard Of Sinkhole Flooding To A Cave Hominin Site And Its Control Countermeasures In A Tower Karst Area, South China, Fang Guo, Guanghui Jiang, Kwong Fai Andrew Lo, Qingjia Tang, Yongli Guo, Shaohua Liu 2015 Institute of Karst Geology, Chinese Academy of Geological Sciences

Hazard Of Sinkhole Flooding To A Cave Hominin Site And Its Control Countermeasures In A Tower Karst Area, South China, Fang Guo, Guanghui Jiang, Kwong Fai Andrew Lo, Qingjia Tang, Yongli Guo, Shaohua Liu

Sinkhole Conference 2015

Zengpiyan Cave, one of the most important cave hominin sites of the Neolithic in the South of China, was listed on the national register of cultural preservation sites in 2001. Large quantities of precious material in the Zengpiyan site were unearthed since the beginning of the trial excavation in 1973. These materials include hominin skeletal remains, fire pits, human burials, stone implements, tools fashioned from mollusk shells and animal or plant fossils. According to the historical record, ancient people lived in caves in the karst plain of Guilin. They moved out of the caves approximately 7000 years ago. These cave …


Study On Monitoring And Early Warning Of Karst Collapse Based On Botdr Technique, Zhende Guan 2015 Institute of Karst Geology, CAGS

Study On Monitoring And Early Warning Of Karst Collapse Based On Botdr Technique, Zhende Guan

Sinkhole Conference 2015

Brilliouin Optical Time Domain Reflectometer (BOTDR) is a newly developed measurement and monitoring technique, which utilizes Brilliouin spectroscopy and Optical Time Domain Reflectometer (Jiang et al., 2006; Zhang et al., 2009; Xu et al.,2011) to measure strain generated in optical fibers as distributed in the longitudinal direction. This paper introduces the principle and characters of BOTDR technique firstly, and makes an example of karst collapse monitoring at section K14 of highway from Guilin to Yangshuo. And we talk about how to use this technique in underlying karst collapse monitoring in karst highway, discuss environmental factors, like temperature and vehicle dynamic …


Karst Spring Cutoffs, Cave Tiers, And Sinking Stream Basins Correlated To Fluvial Base Level Decline In South-Central Indiana, Garre A. Conner 2015 Pangea Geoservices

Karst Spring Cutoffs, Cave Tiers, And Sinking Stream Basins Correlated To Fluvial Base Level Decline In South-Central Indiana, Garre A. Conner

Sinkhole Conference 2015

The Mitchell Aquifer averages 80m in thickness and underdrains a karst region in the Crawford Upland and Mitchell Plateau region in south-central Indiana (110,000 km2). The Springville Escarpment is a transitional boundary between the upland and plateau. Cave stream linking between cave tiers in the aquifer and correlation of cave tier inception horizons to a base level decline surface is interpreted for the Kirby Watershed, encompassing the prekarst headland of Indian Creek (42km2). The watershed was severed from lower Indian Creek at Eller Col by limestone cavern drainage on the ridge between White River and East Fork. Correlation of recharge …


Tracer Studies Conducted Nearly Two Decades Apart Elucidate Groundwater Movement Through A Karst Aquifer In The Frederick Valley Of Maryland, Keith A. White, Michael K. Cobb, Thomas Aley, Ethan Weikel 2015 ARCADIS, Inc.

Tracer Studies Conducted Nearly Two Decades Apart Elucidate Groundwater Movement Through A Karst Aquifer In The Frederick Valley Of Maryland, Keith A. White, Michael K. Cobb, Thomas Aley, Ethan Weikel

Sinkhole Conference 2015

A pair of groundwater tracer studies at a single karst test site were completed 18 years apart. The results of these studies have provided evidence of both relatively rapid advective transport via conduits and an extreme capacity for dye storage and retardation. The tracer results, coupled with other subsurface investigation data, are used to develop a conceptual model for groundwater movement through this karst aquifer in the Frederick Valley of Maryland, as well as identify implications for remediation. Three fluorescent tracer dyes used in the initial study were detected in several background monitoring locations established for the second study conducted …


Integration And Delivery Of Interferometric Synthetic Aperture Radar [Insar] Data Into Stormwater Planning Within Karst Terranes, Brian Bruckno, Andrea Vaccari, Edward Hoppe, Scott Acton, Elizabeth Campbell 2015 University of Nebraska-Lincoln

Integration And Delivery Of Interferometric Synthetic Aperture Radar [Insar] Data Into Stormwater Planning Within Karst Terranes, Brian Bruckno, Andrea Vaccari, Edward Hoppe, Scott Acton, Elizabeth Campbell

Department of Earth and Atmospheric Sciences: Faculty Publications

As part of two USDOT-funded studies focused on the development of satellite-based Interferometric Synthetic Aperture Radar (InSAR) technology, the researchers integrated InSAR-derived point cloud data into the transportation design process to optimize the location of a stormwater management system in a karst terrane. After initial validation, the InSAR data (over 1.67 million data points comprising various “scatterers”) were brought into a GIS dataframe and georeferenced to locations of known sinkholes. This dataset was then used to evaluate karst hazard within a 40x40km data frame located in the Valley and Ridge Province of Virginia. The group identified systematic kinematic differences in …


Investigations Of The Presence Of Caffeine In The Rudawa River, Kraków, Poland, Agnieszka Jagoda, Witold Zukowski, Barbara Dąbrowska 2015 Cracow University of Technology

Investigations Of The Presence Of Caffeine In The Rudawa River, Kraków, Poland, Agnieszka Jagoda, Witold Zukowski, Barbara Dąbrowska

Witold Zukowski

Caffeine concentration in surface water (Rudawa River, Kraków, Poland) has been being investigated since 2011. The method applied for investigations was developed in 2011, and the first series of measurements of caffeine concentration in surface water began in 2011. Caffeine concentration was determined by the gas chromatography-mass spectrometry (GC-MS) method. Solid phase extraction (SPE) was used to enrich the concentration of caffeine in water samples. As an internal standard, the caffeine isotope (13)C3 in methanol (Sigma Aldrich) was used. The values of four additional parameters (concentration of nitrates, biochemical oxygen demand after 7 days, number of Escherichia coli and number …


Label-Free Surface-Enhanced Raman Spectroscopy-Linked Immunosensor Assay (Slisa) For Environmental Surveillance, vinay bhardwaj 2015 Florida International University

Label-Free Surface-Enhanced Raman Spectroscopy-Linked Immunosensor Assay (Slisa) For Environmental Surveillance, Vinay Bhardwaj

FIU Electronic Theses and Dissertations

The contamination of the environment, accidental or intentional, in particular with chemical toxins such as industrial chemicals and chemical warfare agents has increased public fear. There is a critical requirement for the continuous detection of toxins present at very low levels in the environment. Indeed, some ultra-sensitive analytical techniques already exist, for example chromatography and mass spectroscopy, which are approved by the US Environmental Protection Agency for the detection of toxins. However, these techniques are limited to the detection of known toxins. Cellular expression of genomic and proteomic biomarkers in response to toxins allows monitoring of known as well as …


Spatial Variability Of Subsurface Soil Conditions Causing Roadway Settlements, Ömer Bilgin, Kevin Arens, Mark Salveter, Alexander Dettloff 2015 University of Dayton

Spatial Variability Of Subsurface Soil Conditions Causing Roadway Settlements, Ömer Bilgin, Kevin Arens, Mark Salveter, Alexander Dettloff

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Settlement of problematic soils constituting the roadway subgrade may result in pavement distress and structural failure, requiring periodic pavement patching and resurfacing. Many of these problems occur as a result of the settlement of soft cohesive and organic soils. Due to the extent of roadway projects and the limited frequency of boring locations, spatial variability of subsurface soil conditions, and sometimes due to an inadequate extent of exploration, these problematic soils may not be identified suitably during subsurface explorations. An extensive subsurface exploration program was implemented for detailed characterization of subsurface conditions for a relatively short section of an existing …


The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai 2015 Marquette University

The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai

Dissertations (1934 -)

Anaerobic digestion (AD), the conversion of complex organic matter to methane, occurs through a series of reactions mediated by different guilds of microorganisms. AD process imbalances, such as organic overload or high organic loading rates (OLR), can result in the accumulation of volatile fatty acids (VFA) e.g., propionate, which must be degraded to maintain stable reactor function. VFAs are metabolized by syntrophic fatty-acid degrading bacteria (SFAB) in association with methanogenic archaea (collectively, syntrophic microbial communities, SMC). Despite their indispensable role in AD, little is known about the ecology of SFAB, especially under stressed conditions. To facilitate ecological studies, four quantitative …


Recent Progress In Performance Evaluations And Near Real-Time Assessment Of Operational Ocean Products, Fabrice Hernandez, Edward Blockley, Gary B. Brassington, Fraser Davidson, Prasanth Divakaran, Marie Drévillon, Shiro Ishizaki, Marcos Garcia-Sotillo, Patrick J. Hogan, Priidik Lagemaa, Bruno Levier, Matthew Martin, Avichal Mehra, Christopher Mooers, Nicolas Ferry, Andrew Ryan, Charly Regnier, Alistair Sellar, Gregory C. Smith, Sarantis Sofianos, Todd Spindler, Gianluca Volpe, John Wilkin, Edward Zaron, Aijun Zhang 2015 Institut de Recherche pour le Développement

Recent Progress In Performance Evaluations And Near Real-Time Assessment Of Operational Ocean Products, Fabrice Hernandez, Edward Blockley, Gary B. Brassington, Fraser Davidson, Prasanth Divakaran, Marie Drévillon, Shiro Ishizaki, Marcos Garcia-Sotillo, Patrick J. Hogan, Priidik Lagemaa, Bruno Levier, Matthew Martin, Avichal Mehra, Christopher Mooers, Nicolas Ferry, Andrew Ryan, Charly Regnier, Alistair Sellar, Gregory C. Smith, Sarantis Sofianos, Todd Spindler, Gianluca Volpe, John Wilkin, Edward Zaron, Aijun Zhang

Civil and Environmental Engineering Faculty Publications and Presentations

Operational ocean forecast systems provide routine marine products to an ever-widening community of users and stakeholders. The majority of users need information about the quality and reliability of the products to exploit them fully. Hence, forecast centres have been developing improved methods for evaluating and communicating the quality of their products. Global Ocean Data Assimilation Experiment (GODAE) OceanView, along with the Copernicus European Marine Core Service and other national and international programmes, has facilitated the development of coordinated validation activities among these centres. New metrics, assessing a wider range of ocean parameters, have been defined and implemented in real-time. An …


Techno-Economic Analysis Of Protein Concentrate Produced By Flash Hydrolysis Of Microalgae, Alexander Nana Yaw Asiedu 2015 Old Dominion University

Techno-Economic Analysis Of Protein Concentrate Produced By Flash Hydrolysis Of Microalgae, Alexander Nana Yaw Asiedu

Civil & Environmental Engineering Theses & Dissertations

Process simulation and techno-economic analysis of 95wt.% protein concentrate from microalgae has been performed using SuperPro Designer v. 9.0. This work, first of its kind, is focused on the economic analysis of protein concentrate that includes processes such as microalgae cultivation, harvesting, protein extraction and drying steps. A baseline capacity of 160 MT/day protein concentrate production on commercial basis has been analyzed. This throughput requires 336 MT/day dry algae (54 wt.% protein). The amount of carbon dioxide required to grow this quantum of algae is estimated to be 648 MT/day, which is produced from an in situ 21 MW power …


A Risk Assessment Of The Impacts Of Coastal Flooding And Sea Level Rise On The Existing And New Pump Stations 113, Norfolk, Va, David A. Pezza 2015 Old Dominion University

A Risk Assessment Of The Impacts Of Coastal Flooding And Sea Level Rise On The Existing And New Pump Stations 113, Norfolk, Va, David A. Pezza

Civil & Environmental Engineering Theses & Dissertations

The author assessed the risk to a wastewater pump station and a planned replacement located nearby due to coastal flooding and rising sea levels. The locations for the pump stations are in the Larchmont neighborhood by the Lafayette River tidal estuaries in Norfolk, Virginia. The Lafayette River is a tributary to the Elizabeth River, which flows to the Chesapeake Bay. The low-lying areas along the river are subject to coastal surges caused by tropical and extra-tropical storms that flood the bay.

The region is considered one of the urban areas most exposed to the accelerating rate of rising sea levels. …


Comparing Nutrient Recovery Via Rapid (Flash Hydrolysis) And Conventional Hydrothermal Liquefaction Processes For Microalgae Cultivation, Caleb Richard Talbot 2015 Old Dominion University

Comparing Nutrient Recovery Via Rapid (Flash Hydrolysis) And Conventional Hydrothermal Liquefaction Processes For Microalgae Cultivation, Caleb Richard Talbot

Civil & Environmental Engineering Theses & Dissertations

Algal biofuels have the potential to provide a scalable source of renewable fuels in the near future. The high nutrient use in algae cultivation and its recovery and recycling is one of the challenges that may limit the scalability and sustainability of algal biofuels. The present study evaluates the use of Hydrolysate obtained after Flash Hydrolysis (FH) of Scenedesmus at 280 C as a nutrient source for microalgae cultivation. FH Hydrolysate nutrient recycling was compared with low temperature batch Hydrothermal Liquefaction (HTL) nutrient recycling. Oocystis and Scenedesmus were cultivated using Hydrolysate as a partial phosphorous (P) and nitrogen (N) source. …


Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman 2015 University of Kentucky

Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air–solid interface under variable relative humidity (RH = 0–90%). The maximum reactive uptake coefficient of O3(g) by catechol γO3 = (7.49 ± 0.35) × 10–6 occurs for …


Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian 2015 The University of Western Ontario

Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian

Electronic Thesis and Dissertation Repository

Microbial fuel cells (MFCs) are widely researched for application in wastewater treatment. However, the current anodes used in MFCs often suffer from high fabrication cost and uncontrollable pore sizes. In this thesis, three-dimensional printing technique was utilized to fabricate anodes with different micro pore sizes for MFCs. Copper coating and carbonization were applied to the printed polymer anodes to increase the conductivity and specific surface area. Voltages of MFCs with various anodes were measured as well as other electrochemical tests such as linear sweep voltammetry and electrochemical impedance spectroscopy. 3D copper porous anode produced higher maximum voltages and power densities …


Influence Of Waves On Groundwater Flows And Geochemistry In A Sandy Nearshore Aquifer: A Combined Field And Modelling Study, Spencer S. Malott 2015 The University of Western Ontario

Influence Of Waves On Groundwater Flows And Geochemistry In A Sandy Nearshore Aquifer: A Combined Field And Modelling Study, Spencer S. Malott

Electronic Thesis and Dissertation Repository

Waves are known to influence the flux of pollutants to coastal waters via groundwater discharge. This study combines field measurements with numerical groundwater modelling to evaluate the influence of a period of intensified wave conditions (wave event) on nearshore groundwater flows and geochemistry in a sandy freshwater beach. Comprehensive vertical nested pressure transducer data obtained over a 2.5 day isolated wave event reveal the development of transient groundwater flow recirculations through the nearshore aquifer combined with enhanced water exchange across the sediment-water interface (i.e., beach face). The wave-induced groundwater flows were simulated in FEFLOW using a phase-averaged wave setup approach …


The Effect Of Urbanization On The Embodied Energy Of Drinking Water In Tampa, Florida, Mark Vincent Eli Santana 2015 University of South Florida

The Effect Of Urbanization On The Embodied Energy Of Drinking Water In Tampa, Florida, Mark Vincent Eli Santana

USF Tampa Graduate Theses and Dissertations

Increasing urbanization has serious implications for resource and energy use. One of these resources is drinking water. The increased amount of impervious surfaces associated with urban development is responsible for increased runoff during rain events, which may have a negative impact on the quality of nearby bodies of water, including drinking water sources. The growing populations associated with urbanization require a higher water demand. In addition, urban drinking water systems use energy to collect, treat, and distribute a safe reliable effluent to users. Therefore, this study focuses on the degree to which urbanization influences the embodied energy of drinking water …


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