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Full-Text Articles in Civil and Environmental Engineering

Spatiotemporal Distribution Of Eutrophication In Lake Tai As Affected By Wind, Wenhui Zhang, Qiujin Xu, Xixi Wang, Xiaozhen Hu, Cheng Wang, Yan Pang, Yanbin Hu, Yang Zhao, Xiao Zhao Jan 2017

Spatiotemporal Distribution Of Eutrophication In Lake Tai As Affected By Wind, Wenhui Zhang, Qiujin Xu, Xixi Wang, Xiaozhen Hu, Cheng Wang, Yan Pang, Yanbin Hu, Yang Zhao, Xiao Zhao

Civil & Environmental Engineering Faculty Publications

One common hypothesis is that wind can affect concentrations of nutrients (i.e., nitrogen and phosphorus) and chlorophyll-a (Chl-a) in shallow lakes. However, the tests of this hypothesis have yet to be conclusive in existing literature. The objective of this study was to use long-term data to examine how wind direction and wind speed affect the spatiotemporal variations of total nitrogen (TN), total phosphorus (TP) and Chl-a in Lake Tai, a typical shallow lake located in east China. The results indicated that the concentrations of nutrients and Chl-a tended to decrease from the northwest to the southeast of Lake Tai, with …


Heavy Metal Distribution And Groundwater Quality Assessment For A Coastal Area On A Chinese Island, Sha Lou, Shuguang Liu, Chaomeng Dai, An Tao, Bo Tan, Gangfeng Ma, Roman Sergeeyvich Chalov, Sergey Romanovich Chalov Jan 2017

Heavy Metal Distribution And Groundwater Quality Assessment For A Coastal Area On A Chinese Island, Sha Lou, Shuguang Liu, Chaomeng Dai, An Tao, Bo Tan, Gangfeng Ma, Roman Sergeeyvich Chalov, Sergey Romanovich Chalov

Civil & Environmental Engineering Faculty Publications

Chongming Island is located in the lower Yangtze Estuary in China. Due to the Leachate from a refuse landfill and the hydrodynamics of the Yangtze Estuary, the groundwater environment is particularly complicated on Chongming Island. Field observations were carried out around the landfill disposal site. The groundwater table, temperature, pH, salinity, and dissolved oxygen were measured in the field by portable equipment, and 192 water samples were collected at eight groundwater sites and one surface water site. Through laboratory analysis we found the highest measured concentration of Cr to be 54.07 μg/L, and the measured concentration of Zn was in …


College Of Engineering Senior Design Competition Fall 2016, University Of Nevada, Las Vegas Dec 2016

College Of Engineering Senior Design Competition Fall 2016, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …


Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub Dec 2016

Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub

Electronic Theses and Dissertations

The Delaware Basin of West Texas and southeastern New Mexico is the major western subdivision of the Permian Basin and a northern extension of the Chihuahuan Desert. The major evaporite unit within the Delaware Basin is the Castile Formation, which consists of gypsum/anhydrite and is highly susceptible to dissolution and karsting. Manifestations of karst within the Castile outcrop are abundant and include sinkholes, subsidence features and caves, both epigene and hypogene in origin.

Land reconnaissance surveys conducted during the summer of 2015 documented abundant karst landforms in close proximity to a major thoroughfare, RM 652, in Culberson County, Texas. 2D …


Policy Design Tool For Managing Indoor Residential Water Demand In Water-Scarce Regions, Mujahed M. Thneibat Dec 2016

Policy Design Tool For Managing Indoor Residential Water Demand In Water-Scarce Regions, Mujahed M. Thneibat

Open Access Dissertations

In view of population growth; climate change; and economic evolution, water resources in numerous parts of the world have reached their natural capacities. Consequently, the ability of many countries to grow; meet the basic needs of inhabitants; and protect the environment will be endangered like never before unless water resources are smartly handled and managed. ^ In the past few decades, many developed and developing countries have suffered from water scarcity, and more are certain to follow. The water security dilemma is much more challenging in developing countries. Water utilities have had to follow regulatory plans to manage demand on …


Overseas Chinese Environmental Engineers And Scientists Association (Oceesa) Report, Dec 2016., Yung-Tse Hung, Wen-Chi Ku, Lawrence K. Wang Dec 2016

Overseas Chinese Environmental Engineers And Scientists Association (Oceesa) Report, Dec 2016., Yung-Tse Hung, Wen-Chi Ku, Lawrence K. Wang

Civil and Environmental Engineering Faculty Publications

This Overseas Chinese Environmental Engineers and Scientists Association (OCEESA) report is 2016 Directory of Overseas Chinese Environmental Engineers and Scientists Association (OCEESA), Report number: OCEESA/JL-2016/33D1, December 2016, ISSN 1072 -7248. This report was prepared by Yung-Tse Hung, Permanent Executive Director, OCEESA. This report includes OCEESA contact information, list of OCEESA Directors, list of OCEESA past presidents, OCEESA membership data, constitutions and by laws of OCEESA (5 November 2000 edition), constitutions and by laws of OCEESA (14 February 2006 edition), constitutions and by laws of OCEESA (27 October 2013 edition), membership application form, letter from Wen-Chi Ku to confirm Yung-Tse Hung …


Field Emissions Of (Hydro)Chlorofluorocarbons And Methane From A California Landfill, Alexander H. Sohn Dec 2016

Field Emissions Of (Hydro)Chlorofluorocarbons And Methane From A California Landfill, Alexander H. Sohn

Master's Theses

A comprehensive field investigation was conducted at Potrero Hills Landfill (PHL) located in Suisun City, California to quantify emissions of twelve (hydro)chlorofluorocarbons (i.e. F-gases). The specific target constituents for this study included CFC-11, CFC-12, CFC-113, CFC-114, HCFC-21, HCFC-22, HCFC-141b, HCFC-142b, HCFC-151a, HFC-134a, HFC-152a, and HFC-245fa. The majority of the F-gas emission studies have been conducted outside of the United States and very limited field landfill emission data are available in the United States. Because of historical usage of blowing agents in insulation foams including CFC-11, HCFC-142b, HFC-134a, and HFC-245fa, models reported in literature predicted high F-gas emissions from a landfill …


Spatial Distribution Of Antibiotic Resistance In Soils Receiving Beef Feedlot Runoff, Scott Speicher Dec 2016

Spatial Distribution Of Antibiotic Resistance In Soils Receiving Beef Feedlot Runoff, Scott Speicher

Department of Environmental Engineering: Theses and Other Student Research

A study was conducted to provide new insight on the potential contribution to antibiotic resistance from the land application of beef feedlot runoff to soil. This study reports the distribution and quantity of antibiotic resistant bacteria (ARBs), fecal indicator bacteria (FIB), and antibiotic resistance genes (ARGs) in soil from (i) a field receiving long-term application of beef feedlot runoff holding pond effluent and (ii) a cool-season pasture with no history of supplemental manure application.

Soil samples were collected June 2015 at the U.S. Meat Animal Research Center near Clay Center, Nebraska. A response surface sampling design (RSSD) model based on …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2016

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and permittable option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed Managed Aquifer Recharge (MAR) harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services …


Benchmark Levels For The Consumptive Water Footprint Of Crop Production For Different Environmental Conditions: A Case Study For Winter Wheat In China, La Zhuo, Mesfin Mekonnen, Arjen Y. Hoekstra Nov 2016

Benchmark Levels For The Consumptive Water Footprint Of Crop Production For Different Environmental Conditions: A Case Study For Winter Wheat In China, La Zhuo, Mesfin Mekonnen, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Meeting growing food demands while simultaneously shrinking the water footprint (WF) of agricultural production is one of the greatest societal challenges. Benchmarks for the WF of crop production can serve as a reference and be helpful in setting WF reduction targets. The consumptive WF of crops, the consumption of rainwater stored in the soil (green WF), and the consumption of irrigation water (blue WF) over the crop growing period varies spatially and temporally depending on environmental factors like climate and soil. The study explores which environmental factors should be distinguished when determining benchmark levels for the consumptive WF of crops. …


Simulation Of Value Stream Mapping And Discrete Optimization Of Energy Consumption In Modular Construction, Md Mukul Chowdhury Nov 2016

Simulation Of Value Stream Mapping And Discrete Optimization Of Energy Consumption In Modular Construction, Md Mukul Chowdhury

Theses and Dissertations

With the increased practice of modularization and prefabrication, the construction industry gained the benefits of quality management, improved completion time, reduced site disruption and vehicular traffic, and improved overall safety and security. Whereas industrialized construction methods, such as modular and manufactured buildings, have evolved over decades, core techniques used in prefabrication plants vary only slightly from those employed in traditional site-built construction. With a focus on energy and cost efficient modular construction, this research presents the development of a simulation, measurement and optimization system for energy consumption in the manufacturing process of modular construction. The system is based on Lean …


Pepper Mild Mottle Virus As A Surrogate For Enteric Viruses: Implications For Assessing Water Quality, Erin Michelle Symonds Nov 2016

Pepper Mild Mottle Virus As A Surrogate For Enteric Viruses: Implications For Assessing Water Quality, Erin Michelle Symonds

USF Tampa Graduate Theses and Dissertations

Less than 10% of the world’s domestic wastewater is disinfected prior to discharge into surface waters; therefore, human exposure to diverse wastewater-related pathogens results in millions of cases of illness each year. Among the enteric pathogens, viruses represent an important group of emerging pathogens and are frequently the cause of food- and water-borne outbreaks of illness. Although the World Health Organization and many government agencies mandate the use of bacterial indicators to identify poor microbial water quality, it is well known that these indicators poorly correlate with fecal pollution contamination events and risk of disease. The field of public health-related …


Wind Power: Frustrating Yet Inevitable, Garth Woodruff Nov 2016

Wind Power: Frustrating Yet Inevitable, Garth Woodruff

Faculty Publications

No abstract provided.


Effects Of Surrounding Water Table On A Forested Wetland Habitat In East Coast Of Virginia, Lane Stokes Oct 2016

Effects Of Surrounding Water Table On A Forested Wetland Habitat In East Coast Of Virginia, Lane Stokes

Civil & Environmental Engineering Theses & Dissertations

Exchanges into and out of a wetland, including surface water flow, groundwater flow, and constituents in the flows, usually determine the wetland physicochemical characteristics and biodiversity. To date, of these three exchanges, groundwater flow is the least studied, particularly in the United States of America. In this thesis, field observations were conducted at a forested non-tidal wetland, located on a flat hilltop. The position of the wetland is such that groundwater outflow is the only significant exchange that could be impacted by the surrounding land use. In addition, a spatially variable steady-state model was set up to extrapolate the observations …


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 3 - 2016/06/15), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 3 - 2016/06/15), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/2 - Play 3 - 2016/06/12), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/2 - Play 3 - 2016/06/12), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/3 - Play 1 - 2016/06/08), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/3 - Play 1 - 2016/06/08), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 2 - 2016/06/14), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 2 - 2016/06/14), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/3 - Play 2 - 2016/06/08), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/3 - Play 2 - 2016/06/08), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 1 - 2016/06/10), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 1 - 2016/06/10), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/2 - Play 3 - 2016/06/12), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/2 - Play 3 - 2016/06/12), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1 - Play 1 - 2016/06/07), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1 - Play 1 - 2016/06/07), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10/11 - Play 4 - 2016/06/21), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10/11 - Play 4 - 2016/06/21), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10/11 - Play 4 - 2016/06/21), David Hanson Aug 2016

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10/11 - Play 4 - 2016/06/21), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.


Nanostructured Thin Film Synthesis By Aerosol Chemical Vapor Deposition For Energy Storage Applications, Tandeep Singh Chadha Aug 2016

Nanostructured Thin Film Synthesis By Aerosol Chemical Vapor Deposition For Energy Storage Applications, Tandeep Singh Chadha

McKelvey School of Engineering Graduate Student Theses & Dissertations

Renewable energy sources offer a viable solution to the growing energy demand while mitigating concerns for greenhouse gas emissions and climate change. This has led to a tremendous momentum towards solar and wind-based energy harvesting technologies driving efficiencies higher and costs lower. However, the intermittent nature of these energy sources necessitates energy storage technologies, which remain the Achilles heel in meeting the renewable energy goals. This dissertation focusses on two approaches for addressing the needs of energy storage: first, targeting direct solar to fuel conversion via photoelectrochemical water-splitting and second, improving the performance of current rechargeable batteries by developing new …


Calcium Carbonate Formation In Energy-Related Subsurface Environments And Engineered Systems, Qingyun Li Aug 2016

Calcium Carbonate Formation In Energy-Related Subsurface Environments And Engineered Systems, Qingyun Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Geologic CO2 sequestration (GCS) in subsurface saline aquifers is a promising strategy to mitigate climate change caused by increasing anthropogenic CO2 emissions from energy production. At GCS sites, interactions between fluids and geomedia are important because they can affect CO2 trapping efficiency and the safety of CO2 storage. These interactions include the dissolution and precipitation of minerals. One of the most important minerals is calcium carbonate, because it can permanently trap CO2.

In this work, Portland cement was used as a model geomedium to investigate the chemical reactions, mechanical alterations, transport of reactive fluids, and the interplay of all these …


Exploring Regional And Telecoupled Land Use Change Impacts From Environmental Shocks, Kevin Hill, Liz Wachs, Brady Hardiman, David Yu, Shweta Singh Aug 2016

Exploring Regional And Telecoupled Land Use Change Impacts From Environmental Shocks, Kevin Hill, Liz Wachs, Brady Hardiman, David Yu, Shweta Singh

The Summer Undergraduate Research Fellowship (SURF) Symposium

Natural disasters or environmental shocks have the potential to disrupt local agricultural systems as well as distant agricultural systems through cascading effects. In this work we selected two distinct environmental shocks and traced their cascading effects on land use change. Quantifying cascading effects is a salient issue because climate change forecasts indicate an increase in frequency and intensity of global environmental shocks. This study incorporated the concept of telecoupled systems involving interrelating ecological, economic and political/social components. A telecoupled framework involving cascading effects was implemented using three approaches. The first approach involved using bilateral agricultural trade matrix data to analyze …


The Role Of Organic Matter In The Fate And Transport Of Antibiotic Resistance, Metals, And Nutrients In The Karst Of Northwest Arkansas, Victor Lee Roland Ii Aug 2016

The Role Of Organic Matter In The Fate And Transport Of Antibiotic Resistance, Metals, And Nutrients In The Karst Of Northwest Arkansas, Victor Lee Roland Ii

Graduate Theses and Dissertations

Organic matter (OM) in the environment acts as a nutrient, but may also act as a transport vector for harmful chemical compounds and bacteria. Acetate is a labile form of OM produced during fermentation in anaerobic lagoons used to store animal fecal-waste from concentrated animal feeding operations (CAFOs). Dry and liquid fertilizers from CAFOs pose a threat to groundwater by introducing excessive amounts of nutrients (e.g. OM, nitrate and ammonia), metals, and antibiotic compounds. In the epikarst of Northern Arkansas in the Buffalo River watershed additional input of labile dissolved organic carbon (DOC) from liquid CAFO waste-fertilizers was hypothesized to …


Asbestos Cement Pipe Condition Assessment And Remaining Service Life Prediction, Abiy Melles Ghirmay Aug 2016

Asbestos Cement Pipe Condition Assessment And Remaining Service Life Prediction, Abiy Melles Ghirmay

Graduate Theses and Dissertations

This research details a condition assessment of asbestos cement (AC) pipe within in the Bella Vista Village Property Owners Association water distribution system. Bella Vista Village contains appropriately 300 miles of AC pipe with nominal diameters from 6-14 inch. The goal of the research is to determine the current condition of AC pipe within the system and predict future performance of the pipes. AC pipe samples were obtained from 23 locations disturbed across the distribution system with nominal pipe diameters of 6-8 inch. Estimates of current level of degradation were obtained using phenolphthalein staining and hardness measurements of each sample. …


Evaluating A Measure-Calculate Method For Determining Sediment Oxygen Demand In Lakes, Adrian Beirise Aug 2016

Evaluating A Measure-Calculate Method For Determining Sediment Oxygen Demand In Lakes, Adrian Beirise

Graduate Theses and Dissertations

A steady-state mass diffusion model used with simple measurable and calculable inputs for determining sediment oxygen demand (SOD) is compared to an intact core incubation (ICI) SOD method using samples from three lakes. The mass diffusion model coupled with inputs is known as the measure-calculate method (M-C) and is a potential alternative to existing methods for measuring SOD which are more complex, time-consuming, and costly. The M-C method requires inputs for volumetric sediment oxygen uptake (Ṅsed), sediment density and porosity, and water properties. Ṅsed was determined by suspending sediment in oxygen-saturated water with a DO probe and determining the steady …