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Integration Of Composite Nanomaterials Into Anode And Cathode Designs, Claudia Wuillma Narváez Villarrubia

Chemical and Biological Engineering ETDs

This research introduces the use of bucky' papers based on SWNTs as anode electrode materials for the oxidation of NADH and L-Malate oxidation by poly(methylengreen) and malate dehydrogenase respectively. SWNTs were used to create an electrode design consisting of high surface area-hierarchically ordered carbon nanomaterials with controlled surface chemistry. Additionally, this research introduces new cathodes designs based on buckeye and toray papers for air-breathing and liquid electrolyte modes. Buckeye and 0.11mm-thick toray papers are used to design the air-breathing cathode by immobilization of Laccase using a non-covalent linking agent. The liquid electrolyte cathode, designed to be applied in implantable devices, …

Assessment Of The Biocompatibility, Stability, And Suitability Of Novel Thermoresponsive Films For The Rapid Generation Of Cellular Constructs, Jamie Reed

Chemical and Biological Engineering ETDs

Stimuli responsive polymers (SRP) are of great interest in the bioengineering community due to their use in applications such as drug delivery and tissue engineering. One example of an SRP is poly(N-isopropyl acrylamide) or pNIPAM. This SRP has the capability of changing its conformation with a slight temperature change: adherent mammalian cells spontaneously release as a confluent cell sheet, which can be harvested for cell sheet engineering purposes. Since its initial use in 1968, many researchers have used pNIPAM to obtain a cell sheet composed of their cell type of interest. The differing protocols used for these diverse cell types, …

Synthesis And Characterization Of Cdse-Zns Core-Shell Quantum Dots For Increased Quantum Yield, Joshua James Angell

Master's Theses

Quantum dots are semiconductor nanocrystals that have tunable emission through changes in their size. Producing bright, efficient quantum dots with stable fluorescence is important for using them in applications in lighting, photovoltaics, and biological imaging. This study aimed to optimize the process for coating CdSe quantum dots (which are colloidally suspended in octadecene) with a ZnS shell through the pyrolysis of organometallic precursors to increase their fluorescence and stability. This process was optimized by determining the ZnS shell thickness between 0.53 and 5.47 monolayers and the Zn:S ratio in the precursor solution between 0.23:1 and 1.6:1 that maximized the relative …

Keeping Employees Alive And Well, Farman A. Moayed

Department of Built Environment

No abstract provided.

The Occurrence Of False Positive Tests For Gunshot Residue Based On Simulations Of The Suspect's Occupation, Christopher R. Dockery, Matthew B. Rosenberg, Kimberly Kammerdiener, Lauren E. Mcadams

Faculty Articles

Samples collected from high-risk occupations, or simulations thereof, are analyzed for elemental composition using laser-induced breakdown spectroscopy (LlBS) to determine the occurrence of false positive gunshot residue results generated in the work environment. Previous work involving the study of lifetime of detectable amounts of gunshot residue on the hands of a suspect shooter found that gunshot residue exists up to 5.27 days after a firearm discharge. However, certain environmental and/or occupational false positive tests for gunshot residue could result when sampling non-shooters. Samples collected from occupations or simulations thereof include welding, pyrotechnics, key cutting, mechanics, and paper products all of …

Dynamics Of Oxidized And Reduced Iron In A Northern Hardwood Forest, Colin B. Fuss, Charles T. Driscoll, Chris E. Johnson, Robert J. Petras, Timothy J. Fahey

Civil and Environmental Engineering - All Scholarship

Iron (Fe) is ubiquitous in forest ecosystems and its cycle is thought to influence the development of soil, particularly Spodosols (podsolization), and the biogeochemistry of macronutrients such as carbon (C), nitrogen (N), and phosphorus (P), as well as many trace metals. The cycle of Fe in northern hardwood forests remains poorly understood. To address some of these uncertainties, we constructed a biogeochemical budget of Fe for a small catchment at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, USA. Horizonal, temporal, and elevational patterns of concentrations and fluxes of oxidized and reduced Fe species were assessed …

A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

The application of traditional approaches to the design of efficient facilities can be tedious and time consuming when uncertainty and a number of constraints exist. Queuing models and mathematical programming techniques are not able to capture the complex interaction between resources, the environment and space constraints for dynamic stochastic processes. In the following study discrete event simulation is applied to the facility planning process for a grain delivery terminal. The discrete event simulation approach has been applied to studies such as capacity planning and facility layout for a gasoline station and evaluating the resource requirements for a manufacturing facility. To …

Modeling And Control For Heave Dynamics Of A Flexible Wing Micro Aerial Vehicle Distributed Parameter System, Lisa M. Kuhn

Doctoral Dissertations

In recent years, much research has been motivated by the idea of biologically-inspired flight. It is a conjecture of the United States Air Force that incorporating characteristics of biological flight into air vehicles will significantly improve the maneuverability and performance of modern aircraft. Although there are studies which involve the aerodynamics, structural dynamics, modeling, and control of flexible wing micro aerial vehicles (MAVs), issues of control and vehicular modeling as a whole are largely unexplored. Modeling with such dynamics lends itself to systems of partial differential equations (PDEs) with nonlinearities, and limited control theory is available for such systems.

In …

Nanofabrication Of Halloysite-Pcl Composite Scaffolds And Functionalization Of Titanium For Tissue Regeneration, Shraddha Parshottambhai Patel

Doctoral Dissertations

Major medical needs may be achieved through regenerative medicine. Nanotechnology has triggered a research revolution in many important areas such as the biomedical sciences and bioengineering at the molecular level which has grown significantly due to the availability of new analytical applications and tools based on nanotechnology. Clinical conditions and diseases being targeted by nanotechnology research include burns, Alzheimer's and Parkinson's disease, implant failure, improved wound healing, birth defects, osteoporosis and congestive heart defects. Therapeutic use of growth factors and drugs to stimulate the production and/or function of endogenous cells represents a key area of regenerative medicine. The development of …

Maximum Likelihood Approach To Pointwise Estimation In Statistical Data Processing Under Interval Uncertainty, Nitaya Buntao, Sa-Aat Niwitpong, Vladik Kreinovich

Departmental Technical Reports (CS)

Traditional statistical estimates C(x₁, ..., x_n) for different statistical characteristics (such as mean, variance, etc.) implicitly assume that we know the sample values x₁, ..., x_n exactly. In practice, the sample values X_i come from measurements and are, therefore, in general, different from the actual (unknown) values X_i of the corresponding quantities. Sometimes, we know the probabilities of different values of the measurement error ΔX_i = X_i - x_i, but often, the only information that we have about the measurement error is the upper bound Δ_{i …}

Using A Systemic Model Of Accident For Improving Innovative Technologies: Application And Limitations Of The Stamp Model To A Process For Treatment Of Contaminated Substances, Karim Hardy, Franck Guarnieri

Publications

This paper presents the STAMP accident model, based on systems theory, and describes its application in the context of risk prevention related to the remediation of contaminated materials. The implementation of the model is described, and results are presented both in methodological and technical terms.

Structure And Optical Properties Of Self-Assembled Multicomponent Plasmonic Nanogels, Tao Cong, Satvik N. Wani, Peter Anthony Paynter, Radhakrishna Sureshkumar

Biomedical and Chemical Engineering - All Scholarship

Multicomponent plasmonic nanogels (PNGs) capable of broadband absorption of light in the 400-700 nm wavelength range were synthesized by the self-assembly of metal nanoparticles with wormlike surfactant micelles. Small angle x-ray scattering and rheological experiments suggest that the nanoparticles bridge micelle fragments to aid the formation a stable gel phase with exceptional color uniformity. Their optical absorbance could be robustly tuned by changing the nanoparticle type (Au/Ag), size, shape, and/or concentration. The PNGs have relatively low viscosity and are thermoreversible. Potential applications to the manufacturing of coatings and interfaces for solar energy harvesting and reconfigurable optical devices can be envisioned.

Synthesis And Characterization Of Tethered Poly(N-Isopropylacrylamide) For Quantitative Cell Adhesion Studies, Phanindhar J. Shivapooja

Chemical and Biological Engineering ETDs

Environmentally responsive (or smart') polymers represent a new approach for controlling biofouling release. Poly(N-isopropylacrylamide) (PNIPAAm) is a thermo responsive polymer that can potentially be used to control biofouling, as it exhibits a change in its relative hydrophobicity above and below its lower critical solution temperature (LCST ~ 32\uf0b0C). This thesis reports on grafted PNIPAAm brushes, synthesized using a relatively simple and rapid method which allows atom transfer radical polymerization (ATRP) in presence of air. In this study the structure, purity and thermally responsive behavior of grafted brushes have been characterized using X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectroscopy, Fourier …

Ionic Self-Assembly Of Porphyrin Micro-Nano Structures For Solar Hydrogen Evolution, Yongming Tian

Chemical and Biological Engineering ETDs

This research project develops self-assembled porphyrin micro-nano structures and their metal nanocomposites for efficient solar H2 evolution. The project is composed of three inter-related tasks. The first task is to develop the synthetic methods for preparing the binary porphyrin micro-nano structures by ionic self-assembly under various aqueous solution conditions. Although the porphyrin molecules have been widely studied in artificial photosynthesis, the porphyrin monomers absorb light in a limited range of the solar spectrum and are unstable in solution. In using ionic selfassembly of two oppositely charged porphyrin molecules, we successfully synthesized the more robust micro/nano clover-like structures to replace the …

Biofilter Media Characterization Using Water Sorption Isotherms, Guilherme Del Nero Maia, George B. Day, Richard S. Gates, Joseph L. Taraba

Biosystems and Agricultural Engineering Faculty Publications

Compost material has been used extensively as a gas‐phase biofilter media for contaminant gas treatment in recent years. One of the biggest challenges in the use of this type of material is adequate control of compost moisture content and understanding its effect on the biofiltration process. The present work provides a methodology for characterization of biofilter media under low moisture conditions. Results indicated that low levels of equilibrium moisture content (EMC) were obtained for high levels of equilibrium relative humidity (ERH), i.e., 99% ERH produced EMC of approximately 20% (dry basis) at 25° C. Most bacteria struggle to survive in …

Detection Of Specific Biological Antigens Using Ac Electrochemical Impedance Spectroscopy, Darrel Angelo Mazzari

Dissertations (1934 -)

When certain antigens are present in our environment, a rapid, on-site, accurate, selective, and repeatable detection method can be invaluable in preventing illness or saving lives. Rapid detection of these antigens is important to avert spreading infections.

Currently, capturing a sample and sending it to a laboratory can take weeks to get results, which can be much too long. Conventional sensing methodologies include various electrical measurements as capacitive, potentiometric, piezoelectric, surface plasmon resonance (SPR), and quartz crystal microbalance (QCM). Of particular power and interest is Alternating Current (AC) Electrochemical Impedance Spectroscopy (EIS) which provides for the characterization of the electrical …

Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …

Monitoring Of Mesenchymal Based Constructs Using Magnetic Resonance Elastography, Evan T. Curtis

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Evaluating the functionality of an engineered material lies in the proper characterization of its material and functional properties. In the treatment of musculoskeletal disorders, engineered bone or fat tissue must behave as an adequate replacement else failure of the material could result in discomfort and further surgical procedures. A significant material characteristic that reflects tissue development is the mechanical properties (i.e. shear strength and viscosity). Shear strength and viscosity provide an indication of how efficient the material is in dissipating energy. Energy dissipation occurs naturally in many tissues including fat and can prevent damage to deeper tissues. Many of the …

An Enzymatic Treatment Of Soil-Bound Prions Effectively Inhibits Replication, Samuel Saunders, Jason C. Bartz, Kurt C. Vercauteren, Shannon L. Bartelt-Hunt

Department of Civil and Environmental Engineering: Faculty Publications

Chronic wasting disease (CWD) and scrapie can be transmitted through indirect environmental routes, possibly via soil, and a practical decontamination strategy for prion-contaminated soil is currently unavailable. In the laboratory, an enzymatic treatment under environmentally relevant conditions (22°C, pH 7.4) can degrade soil-bound PrPSc below the limits of Western blot detection. We developed and used a quantitative serial protein misfolding cyclic amplification (PMCA) protocol to characterize the amplification efficiency of treated soil samples relative to controls of known infectious titer. Our results suggest large (104- to >106-fold) decreases in soil-bound prion infectivity following enzyme treatment, demonstrating that a mild enzymatic …

Transport Of Trace Elements In Runoff From Unamended And Pond‐Ash Amended Feedlot Surfaces, Jason R. Vogel, John E. Gilley, Gary L. Cottrell, Brian L. Woodbury, Elaine D. Berry, Roger Eigenberg

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The use of pond ash (fly ash that has been placed in evaporative ponds for storage and subsequently dewatered) for feedlot surfaces provides a drier environment for livestock and furnishes economic benefits. However, pond ash is known to have high concentrations of trace elements, and the runoff water‐quality effects of feedlot surfaces amended with pond ash are not well defined. For this study, two experimental units (plots) were established in eight feedlot pens. Four of the pens contained unamended soil surfaces, and the remaining four pens had pond‐ash amended surfaces. Before each test, unconsolidated surface material was removed from four …

Finding Robust-Under-Risk Solutions For Flowshop Scheduling, Steven O. Kimbrough, Ann Kuo, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

We propose and explore, in the context of benchmark problems for flowshop scheduling, a risk-based concept of robustness for optimization problems. This risk-based concept is in distinction to, and complements, the uncertainty-based concept employed in the field known as robust optimization. Implementation of our concept requires problem solution methods that sample the solution space intelligently and that produce large numbers of distinct sample points. With these solutions to hand, their robustness scores are easily obtained and heuristically robust solutions found. We find evolutionary computation to be effective for this purpose on these problems.

A Probabilistic Analysis Of A Simplified Biogeography-Based Optimization Algorithm, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Biogeography-based optimization (BBO) is a population-based evolutionary algorithm (EA) that is based on the mathematics of biogeography. Biogeography is the study of the geographical distribution of biological organisms. We present a simplified version of BBO and perform an approximate analysis of the BBO population using probability theory. Our analysis provides approximate values for the expected number of generations before the population's best solution improves, and the expected amount of improvement. These expected values are functions of the population size. We quantify three behaviors as the population size increases: first, we see that the best solution in the initial randomly generated …

The Effects Of System Reliability And Time Pressure On Unoccupied Aircraft Systems Operator Performance And Mental Workload, Rania Wageh Ghatas

Doctoral Dissertations and Master's Theses

Unoccupied Aircraft Systems (UAS) are in the midst of aviation`s next generation. UAS are being utilized at an increasing rate by military and security operations and are becoming widely popular in usage from search and rescue and weather research to homeland security and border patrol. The Federal Aviation Administration (FAA) is currently working to define acceptable UAS performance standards and procedures for routine access for their use in the National Airspace System (NAS). This study examined the effects of system reliability and time pressure on unoccupied aircraft systems operator performance and mental workload. Twenty-four undergraduate and graduate students, male and …

Noninvasive Imaging Of The Human Rod Photoreceptor Mosaic Using A Confocal Adaptive Optics Scanning Ophthalmoscope, Alfredo Dubra, Yusufu N. Sulai, Jennifer L. Norris, Robert F. Cooper, Adam M. Dubis, David R. Williams, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

The rod photoreceptors are implicated in a number of devastating retinal diseases. However, routine imaging of these cells has remained elusive, even with the advent of adaptive optics imaging. Here, we present the first in vivo images of the contiguous rod photoreceptor mosaic in nine healthy human subjects. The images were collected with three different confocal adaptive optics scanning ophthalmoscopes at two different institutions, using 680 and 775 nm superluminescent diodes for illumination. Estimates of photoreceptor density and rod:cone ratios in the 5°–15° retinal eccentricity range are consistent with histological findings, confirming our ability to resolve the rod mosaic by …

Statistical Optimizations Of Muscle Action Potentials Based On Modeling And Analysis Of Ion Channel Dynamics, Gyutae Kim

Electrical & Computer Engineering Theses & Dissertations

An Electromyogram (EMG) is an electrical signal, which is measured from a skeletal muscle during voluntary and involuntary contractions. EMGs are useful in interpreting pathological states of the musculoskeletal system. In particular, EMGs offer valuable information concerning the timing of muscular activity and its relative intensity. Various EMG models have developed with many different purposes from a pure mathematical model to a pattern structure model [17,46]. Sophisticated EMG models are necessary to examine the effects of small changes in muscular morphology and activities [46]. Due to the crucial importance of EMG models, all factors in the model should be precise …

The Tracking Performance Of Distributed Recoverable Flight Control Systems Subject To High Intensity Radiated Fields, Rui Wang

Electrical & Computer Engineering Theses & Dissertations

It is known that high intensity radiated fields (HIRF) can produce upsets in digital electronics, and thereby degrade the performance of digital flight control systems. Such upsets, either from natural or man-made sources, can change data values on digital buses and memory and affect CPU instruction execution. HIRF environments are also known to trigger common-mode faults, affecting nearly-simultaneously multiple fault containment regions, and hence reducing the benefits of n-modular redundancy and other fault-tolerant computing techniques. Thus, it is important to develop models which describe the integration of the embedded digital system, where the control law is implemented, as well …

Automatic High-Fidelity 3d Road Network Modeling, Jie Wang

Computational Modeling & Simulation Engineering Theses & Dissertations

Many computer applications such as racing games and driving simulations frequently make use of 3D high-fidelity road network models for a variety of purposes. However, there are very few existing methods for automatic generation of 3D realistic road networks, especially for those in the real world. On the other hand, vast road network GIS data have been collected in the past and used by a wide range of applications, such as navigation and evaluation. A method that can automatically produce 3D high-fidelity road network models from 2D real road GIS data will significantly reduce both the labor and time needed …

A Systemic Approach To Next Generation Infrastructure Data Elicitation And Planning Using Serious Gaming Methods, Ersin Ancel

Engineering Management & Systems Engineering Theses & Dissertations

Infrastructure systems are vital to the functioning of our society and economy. However, these systems are increasingly complex and are more interdependent than ever, making them difficult to manage. In order to respond to increasing demand, environmental concerns, and natural and man-made threats, infrastructure systems have to adapt and transform. Traditional engineering design approaches and planning tools have proven to be inadequate when planning and managing these complex socio-technical system transitions. The design and implementation of next generation infrastructure systems require holistic methodologies, encompassing organizational and societal aspects in addition to technical factors. In order to do so, a serious …

Unintended Consequences: Potential Downsides Of The Air Force's Conversion To Biofuels, Mark N. Goltz, Charles A. Bleckmann, Charles M. Mackay, Khai Vuong, Jerrod P. Mccomb

Faculty Publications

The desire to reduce US dependence on foreign energy, ongoing environmental concerns, and the rising cost of petroleum have sparked significant development of greener alternative and renewable energy sources such as alcohol-based biofuels. To address these issues, the Department of Defense DOD has moved to diminish its reliance on petroleum for fueling aircraft and ground equipment. The US Air Force, in alignment with DOD objectives, has initiated several goals for reducing its use of energy: (1) decrease the use of petroleum-based fuel by 2 percent annually for the vehicle fleet, (2) increase the use of alternative fuel in motor vehicles …

Using Nanotechnology To Detect Nerve Agents, Mark N. Goltz, Dong-Shik Kim, Leeann Racz

Faculty Publications

Nanotechnology has opened a wide range of opportunities having potential impacts in areas as diverse as medicine and consumer products. In collaboration with researchers at the University of Toledo UT, Air Force Institute of Technology AFIT scientists are exploring the possibility of using a nanoscale organic matrix to detect organophosphate OP nerve agents. Current techniques for detecting OP compounds are expensive and time consuming. Developing a nanoscale organic matrix sensor would allow for direct, real-time sensing under field conditions. This article describes the science behind such a sensor and its possible applications. High-performance sensors are needed to protect Soldiers and …