Physical Sciences and Mathematics Commons^™

Experimental And Numerical Investigation Of The Effect Of Fuel Composition On Flame Stability On A Gas Turbine Combustor, Gilberto Corona

Open Access Theses & Dissertations

Gas turbines are used for power generation and aviation all over the world. Fossil fuels remain the main source of energy for the operation of gas turbines but the recent increase in environmental awareness has influenced government agencies to impose stringent limits on pollutant emissions from power generation plants. Pollutant emissions control is one of the major challenges for gas turbine designers. In this study, experimental methods and computational fluid dynamics (CFD) technologies are used to study the problems that arise when coal derived fuels are used in Gas Turbine Combustors.

Gas turbine designers need both experimental data and combustion …

Influence Of Orography On The Weather Patterns And Water Availability Of A Topographically Complex Chihuahuan Desert Region, Fernanda De La Cerda Camargo

Open Access Theses & Dissertations

Arid and semi-arid ecosystems cover a large extent of the planet's land surface and are highly susceptible to/and dependent on resource availability patterns, especially precipitation. Topography affects large scale weather patterns and redistributes precipitation which creates a variety of microclimates in complex landscapes; how these patterns are modified, however, is still not fully understood. Climate change models for arid and semi-arid ecosystems predict a change towards more extreme precipitation events; understanding the mechanisms involved in redistributing precipitation is crucial for the protection of these areas. Indio Mountains Research Station (IMRS) is located in the northern Chihuahuan Desert and seems to …

Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos

Open Access Theses & Dissertations

Environmental scientists use advanced sensor technology such as meteorological towers, wireless sensor networks and robotic trams equipped with sensors to perform data collection at remote research sites. Because the amount of environmental sensor data acquired by such instruments is increasing, the ability to evaluate the accuracy of the data at collection time and to check that the instrumentation is operating correctly become critical in order to not lose valuable time and information. The goal of the research is to define a solution, based on software-engineering techniques, to support the scientist's ability to specify data properties that can identify anomalies in …

Development Of A Low-Cost Network Of Webcams For Monitoring Plant Phenology In A Chihuahuan Desert Shrubland, Libia Gonzalez

Open Access Theses & Dissertations

Phenology is the study of the timing of natural events such as the schedule of plant life-cycle events like bud burst, flowering, seed set and senescence. Many factors control plant phenological dynamics including climate. As such, phenology has been shown in published literature to be one of the best biological indicators of climate variability and change. Recent advantages in digital photography and digital image processing have opened new opportunities for inexpensive, repeatable and automated capture of plant and landscape phenological dynamics. This technology, however, remains poorly studied in terms of its capacity to depict the development of different plant phenophases, …

Investigation On Flame Characteristics Of Oxy-Fuel Combustion, Md R. Islam

Open Access Theses & Dissertations

Oxy-fuel combustion is currently being considered by the U.S Department of Energy as a promising technology for efficient carbon capture. This technology could substantially reduce NOx and CO2 emissions. In addition, the implementation of oxy-fuel combustion technology in a power generation system could potentially reduce negative environmental impacts of fossil fuel use. It also encourages the use of reliable and domestic energy sources. The U.S. Department of Energy has made efforts to investigate the performance of a CO2 and H2O diluted oxy-fuel combustion system in a high-pressure combustor. In an effort to better understand and characterize the fundamental flame characteristics …

Patterns And Controls Of Erosion Along The Barrow Environmental Observatory Coastline, Northern Alaska, Adrian Aguirre

Open Access Theses & Dissertations

With pronounced arctic warming that is linked to loss of sea ice, sea level rise, and land cover change, over the coming decades arctic coastal regions are likely to undergo amongst the most dramatic changes of any ecosystem on Earth. This study used foot surveys and a Differential Global Positioning System (DGPS) to document at a high spatial (horizontal and vertical) resolution, the spatiotemporal dynamics of the eroding bluff along the coastline of the Barrow Environmental Observatory between 2003 and 2009. The coastline consists of an eroding bluff bordered by a shallow muddy lagoon. The coast is protected from strong …

Incorporating Sustainability Into Urban Infrastructures: The Tension Between Bio-Cultural Aspects And Environmental Considerations, Shane Epting

Open Access Theses & Dissertations

The following arguments focus on how to think about sustainability as it relates to technology and the non-human world within an anthropocentric framework. We end up with a picture showing that humankind needs to change the ways in which we look at anthropocentric concerns. Secondly, the discussion that leads up to the final picture details the urgency that guides the thinking behind the implementation of sustainability. Because, as the West learns to live in an entirely new sense that is consistent with holding humankind's desire for existence as a permanent situation, one finds that this notion must be paramount for …

Comparison Of Two Environmental Health Education Methods To Reduce Exposure To Residential Pesticides In Hispanic, Patricia M. Juarez-Carrillo

Open Access Theses & Dissertations

ABSTRACT

Exposure to pesticides is associated with adverse health outcomes including poisonings, short-term signs and symptoms, and long-term adverse health outcomes including developmental and cognitive impairments, certain types of cancer, and damages to the endocrine, nervous, and reproductive systems. This study tested two educational methods aimed to help Hispanic, Spanish-speaking mothers living in the U.S.-México border make informed decisions about pesticides applied in their homes. 230 women were randomly allocated to a) a small group talk, b) a graphic booklet, or c) a control group. The outcomes were the knowledge level about the risks of pesticides and the pest prevention …

Adaptation Of Low Impact Design To The Desert Southwest, Abubaker Ali Alamailes

Open Access Theses & Dissertations

A low Impact Development (LID) practices were used to design an Integrated Management Practices (IMP) system for a residential lot .The design was adapted to the Desert Southwest region based on twenty years of climate data including precipitation and temperature for three representative cities: El Paso, TX, Albuquerque, NM, and Phoenix, AZ. In order to capture stormwater runoff close to its source and to provide as much stored water as possible for plants, LID practices including bioretention cells and vegetated swales were applied throughout the lawn. The purpose of the design is to maintain the pre-development hydrologic characteristics of the …

Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel

Open Access Theses & Dissertations

In the last two decades, synchrotron based techniques have gained popularity and been increasingly used in environmental sciences. The present dissertation has relied significantly in the use of synchrotron based techniques to study the speciation, coordination, and distribution of toxic metal(loids) in plants. This study included three plant species: Parkinsonia florida, Prosopis juliflora, and Zea mays. P. florida is a plant species native to the semi-desert regions of North America. The cultivation characteristics of this shrub/tree suggest that it could be used for phytoremediation purposes in semiarid regions. P. florida plants were tested for their capacity to remove arsenic (As) …

Monitoring Ecosystem Dynamics In An Arctic Tundra Ecosystem Using Hyperspectral Reflectance And A Robotic Tram System, Santonu Goswami

Open Access Theses & Dissertations

Global change, which includes climate change and the impacts of human disturbance, is altering the provision and sustainability of ecosystem goods and services. These changes have the capacity to initiate cascading affects and complex feedbacks through physical, biological and human subsystems and interactions between them. Understanding the future state of the earth system requires improved knowledge of ecosystem dynamics and long term observations of how these are being impacted by global change. Improving remote sensing methods is essential for such advancement because satellite remote sensing is the only means by which landscape to continental-scale change can be observed.

The Arctic …

Quality Of Wastewater In The El Paso, Texas Region--Analysis Of Pharmaceuticals And Personal Care Products Using High Performance Liquid Chromatography Tandem Mass Spectrometry, Rodolfo Guerrero Jr.

Open Access Theses & Dissertations

Pharmaceuticals and Personal Care Products (PPCPs), such as household cleaning materials, prescription medication, and personal hygiene products, are pollutants of emerging concern that are found in 80% of our water system. Because of their applications, PPCPs are subsequently being released into wastewater; however, current wastewater treatment facilities are not regulated or designed to remove PPCPs. Therefore, these compounds are discharged into the environment on a continual basis. The effects of PPCPs on human health are not yet well known; however, recent research has found that exposure to these chemicals has some adverse developmental effects on aquatic species at low concentrations …

Application Of The Water Poverty Index In Border Colonias Of West Texas, Marcelo Korc

Open Access Theses & Dissertations

This study applied the Water Poverty Index (WPI) in border colonias and other rural areas of west Texas. The colonias are mostly unincorporated communities located primarily in New Mexico and Texas along the border with Mexico and are characterized by high poverty rates and substandard living conditions. In Texas, access to drinking water and sanitation services has been identified as one of the most significant determinants of health in over 350 colonias with about 50 thousand residents.

The WPI is a multidimensional measure that links household welfare with water availability. WPI components were identified and prioritized by a wide range …

An Experimental Study On The Effect Of Particle Geometry On Drag And Flow Behaviors In A Packed Fluidized Bed, Md Mahamudur Rahman

Open Access Theses & Dissertations

Gasification offers a promising solution to producing fuels effectively in the coming years by providing a low-cost energy system, clean environmental performance, and reliability. Feedstock is prepared and fed to a gasifier in either a dry form or as slurry (mixed with water). One application of this technology uses heat, pressure, and steam to convert feedstock into a gaseous mixture, composed primarily of carbon monoxide (CO) and hydrogen (H2), named as syngas. Several technical and commercial issues were identified by the Nation Energy Technology Laboratory (NETL) in 2006 Multiphase workshop. US Department of Energy (DOE) is now focusing on attaining …

Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez

Open Access Theses & Dissertations

Assessing the quality of sensor data in environmental monitoring applications is important, as erroneous readings produced by malfunctioning sensors, calibration drift, and problematic climatic conditions, such as icing or dust, are common.Traditional data quality checking and correction is a painstaking manual process, so the development of automatic systems for this task is highly desirable.

This study investigates machine learning methods to identify and clean incorrect data from a real-world environmental sensor network, the Jornada Experimental Range, located in Southern New Mexico. We evaluated several learning algorithms and data replacement schemes, and developed a method to identify the problematic sensor. The …

Joint Geophysical Data Analysis For Geothermal Energy Exploration, Antony Munika Wamalwa

Open Access Theses & Dissertations

Geophysical data modelling often yields non-unique results and hence the interpretation of the resulting models in terms of underlying geological units and structures is not a straightforward problem. However, if multiple datasets are available for a region of study, an integrated interpretation of models for each of the geophysical data may results to a more realistic geological description. This study not only demonstrates the strength of resistivity analysis for geothermal fields but also the gains from interpreting resistivity data together with other geophysical data such as gravity and seismic data. Various geothermal fields have been examined in this study which …

Analysis Of Endocrine Disrupting Compounds In Wastewater Treatment Plants: A Perspective Of Trans-Boundary Waterborne Pollution, Roberto De La Torre

Open Access Theses & Dissertations

Recent decades have brought an increasing concern of potential adverse human and ecological health effects resulting from Endocrine Disruptor Compounds (EDCs). In particular from new emerging compounds such as natural estrogens (e.g., 17©¬-estradiol, estrone), synthetic estrogens (e.g., 17Â¥á-ethynylestradiol), bisphenol A (BPA), nonylphenol ethoxylates (NPEOS), and nonylphenol (NP). These chemicals which are also known as organic wastewater contaminants are released directly to the environment after passing through wastewater treatment plants (WWTPs), which often are not designed to remove them from the effluent. The occurrence of the aforementioned compounds in surface water is becoming of increasing concern worldwide, and has led to …

Development Of A Web-Based Geographic Information System For Arctic Science, George Walker Johnson

Open Access Theses & Dissertations

Environmental science is a large field of study that requires the acquisition of data for decision making in solving environmental issues. Leveraging desktop geographic information systems (GIS) and web-based GIS (WebGIS) systems for assisting in the problem solving processes can benefit both the research community and policy makers for decision making activities. Ensuring interoperability between desktop, web, and server GIS is essential for maximizing access, sharing and manipulation of data. Interoperability is maximized through the adoption of best practices, use of open standards, and utilization of Spatial Data Infrastructures (SDI). While many of the interoperability challenges such as infrastructure, data …

Assessment Of Intra-Urban Traffic-Related Air Pollution On Asthmatic Children's Exposure At Schools In The Paso Del Norte Region, Amit Ugamraj Raysoni

Open Access Theses & Dissertations

Traffic-related air pollution can be a major public health concern in any urban area. This problem is compounded in the Paso del Norte region that has experienced rapid economic growth, and a substantial number of people living in close vicinity of major roadways. The desert surroundings, arid weather, frequent temperature inversions, heavy border traffic at the international ports of entry between El Paso and Ciudad Juárez, and poorly maintained vehicle fleet further exacerbates this problem. A growing body of air quality and epidemiologic research has discerned the linkage between traffic emissions and respiratory disorders.

Initial health investigations in the Paso …

Airborne Lead In El Paso, 1977-1999, Ingrid B. Camacho

Open Access Theses & Dissertations

Airborne lead is an important component of the biogeochemical make-up of ambient air. Most of the lead emitted to the atmosphere has been in the form of particulate matter.

This study evaluated airborne lead levels in the El Paso airshed at different intervals over the span of three decades between 1977 and 1999. Levels of lead and related metals for a number of years and from a number of sampling stations in El Paso were available from Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analyses previously conducted in Prof. Pingitore's laboratory at UTEP.

Data consisted of some 200 samples, each a …

Development Of An Expert System To Aid In The Selection Of Sustainability Design Engineering Methods, Pedro Renato Acosta

Open Access Theses & Dissertations

The objective of this thesis is to present the development of an expert system to aid designers in the selection of design methods, in particular for sustainability methods. When practicing engineers need help in their design process, they look for design methods and tools; this is a challenge especially for inexperienced engineers in the sustainability area. Engineers, due to time constrains, will only utilize one or few methods during their professional life. The origin of this situation can be traced to engineering education, where it is typical that an instructor prefers one or few methods in particular, and even when …

Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady

Open Access Theses & Dissertations

For some environmental science applications, Unmanned Aircraft Systems (UASs) are increasingly recognized for their capacity to collect remotely sensed data in a safer, more efficient and effective manner than is permitted with manned aircraft and satellite remote sensing platforms. To date, however, technological, human, and other challenges have constrained adoption of UASs in the environmental sciences. This study developed and tested a new UAS for an archetypical environmental science research group (stakeholder) composed of non-UAS experts. Specifically, this thesis: 1) Assessed the research and operational needs of the stakeholder to determine the optimum UAS platform; 2) Developed an Unmanned Aerial …

Asphaltene As Light Harvesting Material In Dye Sensitized Solar Cell, Rajab Emhemed Abujnah

Open Access Theses & Dissertations

This Dissertation characterizes the first asphaltene DSSC (dye-sensitized solar cell), in which light to electricity conversion efficiency has improved from 0 % to 1.8 %. Four natural organic asphaltene factions, namely, un-fractionated asphaltene, Fr. 1 Asphaltene, Fr.2 asphaltene, Fr.3 and Fr.4 were extracted and tested for various solar cell parameters of TiO2 based dye-sensitized solar cell DSSC. DSSCs were fabricated using the four individual asphaltene dyes. The photovoltaic performance of the cells was examined by determining the various parameters such as open-circuit voltage, short-circuit current, fill factor, and series resistance. The overall energy conversion efficiency was also measured to correlate …

A Framework For Strategic Sustainable Supply Chain Design, Abril Paola Vazquez

Open Access Theses & Dissertations

Sustainable supply chain management has raised interest considerably in recent years; due to environmental concerns from society as well industries. There is a high interest in the industries to solve this problem but many of the frameworks are directed to specific situation or structure. A strategic sustainable supply chain design framework is presented with the purpose of providing many companies, including small and big industries, the means to maintain an eco-friendly operation. These include; industry plants, distribution centers, and retailers.