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Full-Text Articles in Physical Sciences and Mathematics

Summer Land Surface Temperature: Small-Local Variation In Intro-Urban Environment In El Paso, Tx, Mactar Mohamed Jan 2013

Summer Land Surface Temperature: Small-Local Variation In Intro-Urban Environment In El Paso, Tx, Mactar Mohamed

Open Access Theses & Dissertations

ABSTRACT

It has been well documented that rapid urbanization and population growth have led to the transformation of the natural landscape into anthropogenic urban land and changed such surface physical properties as albedo, energy balance, and surface roughness. Cities, therefore, will be warmer at the urban areas than the rural lands; this situation creates a phenomenon called Urban Heat Island (UHI).

In the recent decades, numerous approaches to study the variation of land surface temperature during daytime have emerged; however, little is known about the variation during nighttime. This study addressed the spatial variation of Summer Nighttime Land Surface Temperature …


Assessing The Equity Implications Of Greenspace Distribution In An Arid Region, Abdelatif Eldeb Jan 2013

Assessing The Equity Implications Of Greenspace Distribution In An Arid Region, Abdelatif Eldeb

Open Access Theses & Dissertations

In the last few decades, vegetation deterioration is receiving increased attention because of its adverse impacts on societal and human health, environmental sustainability, and quality of life. I have selected two cities in Chihuahua Desert region (El Paso and Juarez) as case study sites to develop a novel and applicable methodology for integrating remotely sensed data of different spectral and spatial resolutions into an analysis of the spatial distribution of an urban amenity. The primary objective of this research is to determine if the spatial distribution of greenspace in 2010 is equitable with respect to socio-demographics in El Paso and …


Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley Jan 2013

Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley

Open Access Theses & Dissertations

The last 30 years materials engineers have been under continual pressure to develop materials with a greater temperature potential or to produce configurations that can be effectively cooled or otherwise protected at elevated temperature conditions. Turbines and thrust chambers produce some of the harshest service conditions for materials which lead to the challenges engineers face in order to increase the efficiencies of current technologies due to the energy crisis that the world is facing. The key tasks for the future of gas turbines are to increase overall efficiencies to meet energy demands of a growing world population and reduce the …


Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller Jan 2013

Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller

Open Access Theses & Dissertations

Arctic environments have gained interest recently due to their sensitivity to climate change. As warming has created longer growing seasons, extended ice-free periods as well as permafrost thaw, the production in freshwater ecosystems has the potential to be greatly impacted. It is hypothesized that as climate change and warming occurs, increases in primary production will occur and ponds will become carbon sinks. Net ecosystem production (NEP) was determined using phytoplankton and periphyton samples collected weekly during the growing season (June - August) from arctic tundra ponds near Barrow, Alaska. Enrichment with 14C was used to determine both weekly photosynthetic rates …


Developing A Sustainable Ecotourism Foundation In Indonesian National Parks Using Cross-Cultural Adaptation And Communication Framing, Adriana Salas Jan 2013

Developing A Sustainable Ecotourism Foundation In Indonesian National Parks Using Cross-Cultural Adaptation And Communication Framing, Adriana Salas

Open Access Theses & Dissertations

Previous research on ecotourism in Southeast Asia has focused on its positive and negative effects for conservation. However, the focus in this particular study is to look at what it takes to run a successful ecotourism site in four diverse areas in Indonesia using communication elements like cross-cultural adaptation and communication framing. Communication should be used as a baseline for a successful site and should be used as the most useful tool to address issues and challenges in ecotourism project development.

A successful ecotourism site must carefully look at how their ideas and programs are framed. Ecotourism must also create …


Endocrine Disrupting Compound 4-Nonylphenol And Neurodegeneration, Jessica Martinez Jurado Jan 2013

Endocrine Disrupting Compound 4-Nonylphenol And Neurodegeneration, Jessica Martinez Jurado

Open Access Theses & Dissertations

Neurodegeneration, a progressive loss of nerve cells (neurons), occurs in many neurological disorders including Alzheimer's disease, Parkinson's disease, Schizophrenia, and drug addiction. Cytoskeletal disruption in neurons and aggregation of proteins associated with these disorders is the hallmark of neurodegeneration. However, the cause of neurodegenerative disorders is unknown and currently there are no effective drug treatments. Aging is the most consistent risk factor for developing a neurodegenerative disorder, and recent evidence suggests that environmental factors, which act as endocrine disruptors, pose a risk in the disease process. 4- nonylphenol (4-NP), an endocrine-disrupting compound (EDC), has been shown to affect brain development …


Synthetic Asphaltene As A Novel Dye In Dye Sensitized Solar Cells Dsscs, Hassan Sharif Jan 2013

Synthetic Asphaltene As A Novel Dye In Dye Sensitized Solar Cells Dsscs, Hassan Sharif

Open Access Theses & Dissertations

This dissertation approves the possibility of the first time use of synthetic asphaltene as new dye in dye sensitized solar cells. In which the conversion efficiency of synthetic asphaltene DSSC has improved up to 2.0 %. Synthetic asphaltene sample was prepared from the starting material as in literature and applied for various solar cell parameters of TiO2 based dyesensitized solar cell DSSC. DSSCs were fabricated using the synthetic asphaltene as dye. Different variables and parameters were carried out to test the photovoltaic performance of the cells, these parameters include open-circuit voltage, short-circuit current; fill factor. The first result was obtained …


Pressure And Heat Flux Effects On The Heat Transfer Characteristics Of Liquid Methane, Chance Paul Garcia Jan 2013

Pressure And Heat Flux Effects On The Heat Transfer Characteristics Of Liquid Methane, Chance Paul Garcia

Open Access Theses & Dissertations

The heat transfer effects on liquid methane are investigated with the use of a carbo-thermal rig at the Center for Space Exploration Technology Research (cSETR) located at the University of Texas at El Paso (UTEP). The cSETR carbo-thermal rig design approach is presented along with the design of a methane condensing mobile unit (MCMU) to supply the laboratory and rig with liquid methane. The proposed research will generate useful insight in to heat transfer coefficient behavior, non-dimensional correlations, different flow conditions, varied inlet conditions, and varied heat flux for a subscale test article applicable to a regenerative cooled rocket engine …


Propagation Of Interval And Probabilistic Uncertainty In Cyberinfrastructure-Related Data Processing And Data Fusion, Christian Servin Jan 2013

Propagation Of Interval And Probabilistic Uncertainty In Cyberinfrastructure-Related Data Processing And Data Fusion, Christian Servin

Open Access Theses & Dissertations

Data uncertainty affects the results of data processing. So, it is necessary to find out how the data uncertainty propagates into the uncertainty of the results of data processing. This problem is especially important when cyberinfrastructure enables us to process large amounts of heterogeneous data. In the ideal world, we should have an accurate description of data uncertainty, and well-justified efficient algorithms to propagate this uncertainty. In practice, we are often not yet in this ideal situation: the description of uncertainty is often only approximate, and the algorithms for uncertainty propagation are often not well-justified and not very computationally efficient. …


Investigation Of The Radiative Heat Release Factor Of Premixed Oxy-Syngas Flames, Martin De La Torre Jan 2013

Investigation Of The Radiative Heat Release Factor Of Premixed Oxy-Syngas Flames, Martin De La Torre

Open Access Theses & Dissertations

A significant part of the United States is being powered by combustion devises relying on coal since it is abundant and is a high emitting source of electricity per unit energy, however; the burning of this fuel is responsible for a significant contribution for the pollutant emissions causing global warming. Because coal is one of the main sources of energy in the U.S. and around the globe, the scientific community has been investigating ways to meet current and future governmental emission requirements. It is now well established that radiating heat from the flame is a major contributor of the heat …


An Evaluation Of The Cerro Process As An Efficient Ro Concentrate Management System, Guillermo Guadalupe Delgado Jan 2013

An Evaluation Of The Cerro Process As An Efficient Ro Concentrate Management System, Guillermo Guadalupe Delgado

Open Access Theses & Dissertations

The Concentrate Enhanced Recovery Reverse Osmosis (CERRO) Process is a new method to treat RO concentrate and brackish water with high concentrations of silica and calcium sulfate. Prior investigations have shown that the CERRO process can treat this kind of water without fouling or scaling the membranes, but the main factors that allow the system to operate in such conditions were not studied. The research presented here is an evaluation of the CERRO process as an efficient RO concentrate management system. The parameters of operation of the system were evaluated and improved. The precipitation of calcium sulfate was identified as …


Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob Jan 2013

Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob

Open Access Theses & Dissertations

Numerous studies have been conducted on the modification of local weather by the urban environment. In studying urban environmental effects on the urban heat island (UHI), researchers have investigated influences such as land use, vegetation density, topography, population density, and neighborhood socioeconomic status. Many studies have used data collected from field observations, while other studies relied solely on computer modeling. This Dissertation research used a spatial analysis approach, which has been less widely employed, to investigate neighborhood level biophysical, built environmental and socio-demographic determinants of the El Paso and Juárez UHI. The research utilized inexpensive data obtained from US and …


Interaction Of Ceo2 And Zno Nanoparticles Towards The Symbiotic Association Of Alfalfa (Medicago Sativa) And Sinorhizobium Meliloti In Soil, Susmita Bandyopadhyay Jan 2013

Interaction Of Ceo2 And Zno Nanoparticles Towards The Symbiotic Association Of Alfalfa (Medicago Sativa) And Sinorhizobium Meliloti In Soil, Susmita Bandyopadhyay

Open Access Theses & Dissertations

The production of engineered nanoparticles (ENPs) has rapidly increased due to their wide range of applications in the field of electronics, medicine, chemistry and biology. Consequently, concerns have risen about the environmental release and potential negative impact of NPs. A few reports have described the effects of TiO2 NPs and quantum dots upon nitrogen fixing bacteria. However, the understanding of the interaction of NPs in plant-microbe interface (symbiotic association), like alfalfa (Medicago sativa L.)-Sinorhizobium meliloti, is still in its infancy. Alfalfa is the world's most important forage crop. It grows in association with S. meliloti, which is very important in …


Lead And Associated Heavy Metal Distribution In El Paso, Texas, Ali Ragab Elkekli Jan 2013

Lead And Associated Heavy Metal Distribution In El Paso, Texas, Ali Ragab Elkekli

Open Access Theses & Dissertations

Contamination by lead and other heavy metals is one of the most important environmental concerns of today, locally and globally. This issue has led scientists and researchers to study the effect of heavy metals and their distribution in the environment. The aim of the present research is to document the concentration and geographic distribution of heavy metals in El Paso.

The selected heavy metals in the El Paso soil are lead, cadmium, chromium, zinc, antimony and copper. The soil sample for the study was collected during a previous community lead study (RO1 ESO11367; 2001-2006). 500 superficial soils samples were collected …


Urban Impact Of Dissolved Metals In The Paso Del Norte Segment Of The Rio Grande, Sumayeh Ahmad Freiwan Jan 2013

Urban Impact Of Dissolved Metals In The Paso Del Norte Segment Of The Rio Grande, Sumayeh Ahmad Freiwan

Open Access Theses & Dissertations

The Paso del Norte segment of the Rio Grande experiences two seasons per year; the (wet) irrigation season and the (dry) non-irrigation season. The goal of this study was to improve the understanding of occurrence and contribution of dissolved metals in this region during the non-irrigation season. The objectives of this study were to (1) evaluate the impact of anthropogenic sources of metals on the Rio Grande water quality during the non-irrigation season, and (2) estimate the metal loads carried by the flow to the downstream region of El Paso. In order to evaluate the surface water quality of the …


Lead And Associated Heavy Metal Distribution In Ciudad Juarez, Mexico, Samia Elfituri Grimida Jan 2013

Lead And Associated Heavy Metal Distribution In Ciudad Juarez, Mexico, Samia Elfituri Grimida

Open Access Theses & Dissertations

Concern over the extent and sources of heavy metals exposure has arisen worldwide since their significant effects have been discovered in the environment. There is general agreement that research is needed to examine the residual lead and its association to heavy metals contamination in soil and quantify the health hazards. This research was directed to quantify and document the geographic distribution of lead and associated heavy metals concentration in Ciudad Juarez, Mexico. Lead, cadmium, chromium, zinc, and copper were selected to analysis. The soil samples used in this research were collected during a previous Encountors Binational Community Lead Study (RO1ES …


Determination Of The Effects Of Zno And Ceo2 Nanoparticles In Mesquite (Prosopis Juliflora) And Soybean (Glycine Max): Synchrotron And Spectroscopic Approaches, Jose Angel Hernandez Viezcas Jan 2013

Determination Of The Effects Of Zno And Ceo2 Nanoparticles In Mesquite (Prosopis Juliflora) And Soybean (Glycine Max): Synchrotron And Spectroscopic Approaches, Jose Angel Hernandez Viezcas

Open Access Theses & Dissertations

The rapid growth of nanotechnology is exposing the environment to abnormal concentrations of engineered nanoparticles (NPs). There is concern about the unknown consequences of NPs on the environment and human health. This Dissertation has relied significantly on Synchrotron and other spectroscopic techniques to give insights on the effects, speciation and distribution of two metal oxide nanoparticles (ZnO, CeO2) on two plant species (Mesquite and Soybean). We evaluated the effects of ZnO (10 nm) and CeO2 (8 nm) NPs on a plant species native to the semi-arid regions of North America, Mesquite (Prosopis juliflora velutina). Mesquite plants grown in hydroponic culture …


Toward New Data And Information Management Solutions For Data-Intensive Ecological Research, Christine Marie Laney Jan 2013

Toward New Data And Information Management Solutions For Data-Intensive Ecological Research, Christine Marie Laney

Open Access Theses & Dissertations

Ecosystem health is deteriorating in many parts of the world due to direct and indirect anthropogenic pressures. Generating accurate, useful, and impactful models of past, current, and future states of ecosystem structure and function is a complex endeavor that often requires vast amounts of data from multiple sources and knowledge from collaborating researchers. Ecological data collection has improved rapidly over the past few decades due to the development, innovation, and large scale deployment of automated sensors, which are capable of measuring a gamut of ecosystem properties over broad spatiotemporal scales. Although complex ecosystem models and analyses are increasingly parameterized with …


Assessment Of Water Quality And Benthic Macroinvertebrate Community In A Wastewater Receiving Constructed Wetland, Jennifer Lynn Martinez Jan 2013

Assessment Of Water Quality And Benthic Macroinvertebrate Community In A Wastewater Receiving Constructed Wetland, Jennifer Lynn Martinez

Open Access Theses & Dissertations

In the El Paso region around the 1930s there was a loss of riparian areas and wetlands due to canalization of the Rio Grande. In an attempt to bring back native flora and fauna that once flourished in the floodplain of the Rio Grande region, the creation of Rio Bosque Wetlands Park (RBWP; El Paso Co., TX) was initiated in 1995. As part of the construction agreement, El Paso Water Utilities agreed to provide water to fill the wetland upon its completion. Beginning in 1998, RBWP was filled with treated effluent from the adjacent Roberto Bustamante Wastewater Treatment Plant (WWTP) …


Refining Molecular Approaches For Bacterial Source Tracking (Bst) In Texas, Joy Truesdale Jan 2013

Refining Molecular Approaches For Bacterial Source Tracking (Bst) In Texas, Joy Truesdale

Open Access Theses & Dissertations

Bacterial source tracking (BST) is a new science that aids in identifying sources of human and animal fecal contamination of environmental water. There are currently two approaches used in BST, library-dependent and library-independent methods. The fecal bacterium E. coli is often used in library dependent methods because it indicates fecal contamination, has been used in human health risk assessments, and has water quality regulatory significance. A disadvantage of E. coli library dependent BST methods is that identification libraries of E. coli isolated from known fecal sources are needed to identify the sources of E. coli isolated from water samples. Further, …


Automatic Memory Management Policies For Low Power, Memory Limited, And Delay Intolerant Devices, Md Abu Jahid Jan 2013

Automatic Memory Management Policies For Low Power, Memory Limited, And Delay Intolerant Devices, Md Abu Jahid

Open Access Theses & Dissertations

Mobile devices such as smartphones and tablets are energy and memory limited, and implement graphical user interfaces that are intolerant of computational delays. Mobile device platforms supporting apps implemented in languages that require automatic memory man- agement, such as the Dalvik (Java) virtual machine within Google's Android, have become dominant. It is essential that automatic memory management avoid causing unacceptable interface delays while responsibly managing energy and memory resource usage. Dalvik's automatic memory management policies for heap growth and garbage collection scheduling utilize heuristics tuned to minimize memory footprint. These policies result in only marginally acceptable response times and garbage …


Deprivation And Hispanic Health Paradox: Neighborhood Effects On Children's Wheezing In El Paso, Texas, Young-An Kim Jan 2013

Deprivation And Hispanic Health Paradox: Neighborhood Effects On Children's Wheezing In El Paso, Texas, Young-An Kim

Open Access Theses & Dissertations

This study examines the impact of hypothetical health determinants - including objective and relative economic deprivation, as well as foreign-born composition -at the neighborhood-level on respiratory wheezing among Hispanic children in El Paso, Texas while accounting for individual-level covariates based on hierarchical logistic modeling (HLM). Due to El Paso's majority Latino/a population, focus is placed on the so-called "Hispanic health paradox" through analysis of the impact of neighborhood foreign-born composition on Hispanic children's wheezing. Neighborhood-level variables at the census tract-level are derived from US Census data. The percent of families in poverty and the GINI coefficient for income (income inequality) …


Optimization Of Biomass Logistics System Using Genetic Algorithm And Particle Swarm Optimization For Biofuel Production, Ethel Regina Martinez-Schabez Jan 2013

Optimization Of Biomass Logistics System Using Genetic Algorithm And Particle Swarm Optimization For Biofuel Production, Ethel Regina Martinez-Schabez

Open Access Theses & Dissertations

As time goes by, Renewable Energy keeps proving to be an important and potential replacement for fossil fuels. All the different types of Renewable Energy offer a relief to the environmental aftermaths of the prolonged reliance on fossil fuel energy. Bioenergy is one of the types of Renewable Energy that can help by minimizing the emissions of fossil fuels. The Energy Independence and Security Act mandates the use of 21 billion gallons of advanced biofuels including 16 billion gallons of cellulosic biofuels by the year 2022. Biomass and Biofuels can clearly become a significant aid to sustainably supply energy in …


Carbon Emissions From Soil Respiration In The Northern Chihuahuan Desert Shrubland, Anna Cristina Ortiz Jan 2013

Carbon Emissions From Soil Respiration In The Northern Chihuahuan Desert Shrubland, Anna Cristina Ortiz

Open Access Theses & Dissertations

The United States Department of Agriculture's Jornada Experimental Range (JER), is located in the northern Chihuahuan Desert in southern New Mexico and historically functioned as an experimental rangeland for cattle grazing. Historical grazing in the US Southwest has been identified as a leading, but not the sole, factor that has led to the conversion of pristine grasslands to shrublands, such has been the case on the JER. The estimated increased variability in precipitation intensity and frequency that is predicted to occur with climate warming will likely affect ecosystem responses from ecological processes including primary productivity, microbial decomposition, and thus respiration. …


Geochemical Characterization Of Mineral Dust Sources In The Chihuahuan Desert And Southern High Plains Regions, Porfirio Peinado Jan 2013

Geochemical Characterization Of Mineral Dust Sources In The Chihuahuan Desert And Southern High Plains Regions, Porfirio Peinado

Open Access Theses & Dissertations

The Chihuahuan Desert (northern Chihuahua, southern New Mexico, and far west Texas) and the southern High Plains (west Texas and eastern New Mexico) regions have been identified as one of the most persistent dust producing regions of North America. Regional-scale dust storms have been observed by satellite imagery to identify sources of dust, resulting in collection and examination of physical soil samples to better understand the source signatures (geochemical characteristics) of dust origins in these two regions.

The soil characteristics were examined through several techniques: Particle Size Distribution, X-Ray Diffraction (XRD), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), and Total …


Environmental Education Through The Lens Of Diverse Elementary School Students In The United States: A Phenomenographic Study, Brissa Yazmin Quiroz Jan 2013

Environmental Education Through The Lens Of Diverse Elementary School Students In The United States: A Phenomenographic Study, Brissa Yazmin Quiroz

Open Access Theses & Dissertations

Global environmental change is occurring, putting our planet under pressure. Children need to understand not only why the environment is important, but also their role as citizens of a globalized society and their necessary contribution to solving global problems. Students carry their own perspectives about the environment and education, and these differing perspectives should be a significant topic for environmental education research. Recent research studies have included the conceptualization of nature and the environment through children's eyes; yet, no studies have examined the concept of environmental education through the eyes of diverse children. Minority voices and experiences are not frequently …


Heavy Metal Pollution In The Paso Del Norte Region:Historical Reconstruction And Source Interpretation, Eugenia G. Shekhter Jan 2013

Heavy Metal Pollution In The Paso Del Norte Region:Historical Reconstruction And Source Interpretation, Eugenia G. Shekhter

Open Access Theses & Dissertations

A unique and complex situation of heavy metal pollution arose in the El Paso del Norte region, one of the largest and oldest metropolitan areas on the US-Mexican border. This region with its complex topography is home to more than 2.2 million people sharing the same environment. Although many studies have been conducted in the region to identify the sources of environmental contamination, the cumulative history of heavy metal pollution is still incomplete. In order to identify the patterns of heavy metal dispersion and to test the hypothesis that the American Smelting and Refining Company (ASARCO) was a considerable contributor …


An Approach To Power Efficiency Determination In The Solar Energy Systems Using Central Composite Design And Box-Behnken Design, Juan Venegas Mendez Jan 2013

An Approach To Power Efficiency Determination In The Solar Energy Systems Using Central Composite Design And Box-Behnken Design, Juan Venegas Mendez

Open Access Theses & Dissertations

We are living in an industrialized world that relies on fossil fuels. The ways, in which these fossil fuels have damaged the earth, in special the environment is worth of special attention and corrective actions. In our days, the climate change (global warming) it is becoming the number one topic. These changes are affecting our health, comfort and our way of living. Solar systems have been working among us since several years, but the truth is that most of us really don't understand how they work and more important, how they work in time in different conditions. Solar panels are …


Recovering Magnesium Hydroxide And Sodium Chloride From Zero Discharge Desalination Concentrate Streams, Alemayehu Asfaw Yetayew Jan 2013

Recovering Magnesium Hydroxide And Sodium Chloride From Zero Discharge Desalination Concentrate Streams, Alemayehu Asfaw Yetayew

Open Access Theses & Dissertations

UTEP and Veolia Water Solutions & Technologies have been demonstrating and commercializing the Zero Discharge Desalination (ZDD) technology as part of a three year project sponsored by the U.S. Bureau of Reclamation. ZDD is able to achieve up to 98% recovery by desalinating brackish groundwater. ZDD is typically comprised of a reverse osmosis (RO) or nanofiltration (NF) system and a unique variation of electrodialysis called electrodialysis metathesis (EDM). The ZDD technology increases the yield of fresh water from water supplies that contain enough CaSO4 to cause precipitation problems when the water is treated with RO or NF alone. The EDM …