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Experiments And Modelling Of Micro-Jet Assisted Fluidization Of Nanopowder, Ruud Van Ommen, David M. King, Alan Weimer, Robert Pfeffer, Berend Van Wachem, Samantha Johnson, Niels Looije

10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10

The fluidization of nanoparticle agglomerates can be largely improved by using downward pointing micronozzles, creating a high-velocity jet, as experimentally shown. By discrete particle simulations – treating the agglomerates as single particles – we show that the microjet strongly reduces the amount of gas in voids.

Design Criteria Of Uniflow Cyclones For The Separation Of Solid Particles From Gases, Ulrich Muschelknautz, Paul Pattis, Michael Reinalter, Michael Kraxner

10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10

The main advantages of uniflow cyclones compared to standard reverse flow cyclones are their compact design and their capability of being easily integrated into pipelines. Experiments show that a 0.2m-diameter horizontal uniflow cyclone re-moves 88.6% of 2 g/m3 of fine mineral powder (d10=3m, d50=20m) from 1000 m3/h air at a pressure loss of 2510 Pa (0.364 psi).

Hydrodynamics Of A Cluster Descending At The Wall Of A Cfb Riser - Numerical Study, John R. Grace, Subhashini Vashisth

10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10

The incompressible hydrodynamics of a single parabolic cluster descending at the wall of a CFB riser was numerically simulated using a 2-D Eulerian-Granular model and a segregated time-dependent unsteady solver. Numerical predictions of the velocity of descent and the evolution of cluster shape are in reasonable agreement with experimental results available in the literature.

A Generalized Flow Regime Diagram For Fluid-Solid Vertical Transport, Xiaotao T. Bi

10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10

An ideal generalized flow regime diagram was proposed for fluid-solids vertical transport systems with no bottom and top restrictions. Such an ideal flow regime diagram was further extended to shed light onto the understanding of the flow regimes and instabilities encountered in bottom- restricted bubbling and circulating fluidized bed systems.

Integration Of Communication Constraints Into Physiocomimetic Swarms Via Placement Of Location Based Virtual Particles, Joshua J. Haley

HIM 1990-2015

This thesis describes a change to the Physiocomimetics Robotic Swarm Control framework that implements communication constraints into swarm behavior. These constraints are necessary to successfully implement theoretical applications in the real world. We describe the basic background of swarm robotics, the Physiocomimetics framework and methods that have attempted to implement communications constraints into robotic swarms. The Framework is changed by the inclusion of different virtual particles at a global and local scale that only cause a force on swarm elements if those elements are disconnected from a swarm network. The global particles introduced are a point of known connectivity and …

Fate And Transport Of Escherichia Coli Within Sediment Basins On Active Construction Sites, Elizabeth Tempel

All Theses

The conventional method of controlling sediment-laden runoff on construction sites is the use of sediment basins. These basins slow the velocity of runoff and allow the particles to settle from the water column before discharge to surface waters offsite. This best management practice, however, may create a reservoir for pathogenic bacteria. Sediment is known to provide protection for bacteria; therefore, while these basins decrease sediment loadings to water bodies downstream, they may introduce harmful levels of pathogenic bacteria into these surface waters. In addition to causing human health risks, these high bacteria levels alter natural biological makeup of downstream ecosystems. …

Ultrasonic Methods For The Characterization Of Complex Materials And Material Systems: Polymers, Structured Polymers, Soft Tissue And Bone, Charles Landais

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Understanding the characteristics and structure of materials is of importance in proper modeling and effective design of many products. Complex materials such as polymers, structured material systems, or biological materials provide a particular challenge to many of the traditional methods for doing this. In this dissertation I study the use of ultrasonic wave techniques to characterize several complex materials. These include plastically deformed and aged polycarbonate (PC), a structured PC plate with water filled cavities, bovine bone, and an elastomer used as a skin simulant. In each case, this work was part of a larger project that studied different aspects …

Joule Heating Effects On Electrokinetic Transport In Constriction Microchannels, Sriram Sridharan

All Theses

Microfluidic technology involving multidisciplinary studies including MEMS, chemistry, physics, fluids and heat transfer has been developed into a promising research field in the recent decade. If offers many advantages over conventional laboratory techniques like reduced reagent consumption, faster analysis, easy fabrication and low chemical waste. Microfluidic lab-on-a-chip devices have been used to manipulate cells and particles like sorting, separating, trapping, mixing and lysing. Microfluidic manipulation can be achieved through many methods and insulator based dielectrophoresis (iDEP) is one of the highly used method in the recent years. In iDEP, both DC and AC voltages can be applied to the remote …

Vascular Smooth Muscle Cells In Response To Gold Nanoparticles, William Mcallister

All Theses

In this master's thesis we look at elucidating the interactions between nanoparticles and cells. Specifically, we looked at how the cell mechanics are affected, cytotoxicity of the nanoparticles, and shifts in cell phenotypes. There has been much research looking into whether nanoparticles are cytotoxic, but limited amounts looking at their effect on mechanics especially with vascular smooth muscle cells. This cell type has two distinct phenotypes of synthetic and contractile that each serve different purposes physiologically.
The first experiments we did were cytotoxicity assays to see if the cells could survive the treatment with nanoparticles. If the cells died within …

Investigation Of The Use Of Multi-Criteria Decision-Making Tools For Management Of An Urbanizing Watershed, Reed C. Colton

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The regulation of non-point pollution sources (e.g. agricultural runoff and stormwater discharges) as mandated by the 1972 Clean Water Act, forced a fundamental paradigm shift from “end of the pipe” pollution control to a watershed management approach. Multiple jurisdictions and often conflicting objectives make it difficult to reach stakeholder consensus and execute watershed management decisions. To facilitate decision making when multiple and/or conflicting objectives exist, Multi-Criteria Decision-Making (MCDM) tools were developed for diverse applications, and potentially could be used to facilitate watershed management.

The overall objective of this thesis was to evaluate MCDM tool use to facilitate community-based management of …

Protein Structure-Based Method For Identification Of Horizontal Gene Transfer In Bacteria, Swetha Billa

School of Computing: Dissertations, Theses, and Student Research

Horizontal Gene Transfer is defined as the movement of genetic material from one strain of species to another. Bacteria, being an asexual organism were always believed to transfer genes vertically. But recent studies provide evidence that shows bacteria can also transfer genes horizontally.

HGT plays a major role in evolution and medicine. It is the major contributor in bacterial evolution, enabling species to acquire genes to adapt to the new environments. Bacteria are also believed to develop drug resistance to antibiotics through the phenomenon of HGT. Therefore further study of HGT and its implications is necessary to understand the effects …

Wave Reflection Characteristics Of Permeable And Impermeable Submerged Trapezoidal Breakwaters, Mathew Hornack

All Theses

The present study aims to quantify reflection coefficients in the vicinity of impermeable and permeable submerged trapezoidal breakwaters. Three impermeable breakwater models are tested, each with a unique side slope for the breakwater faces. Two permeable models are tested, one made of PVC pipe and the other consisting of golf balls contained within a mesh cage, to provide two separate porosities. Testing is carried out at the Clemson University Flow Physics Laboratory in a laboratory wave tank with the inclusion of a 1:20 sloping sandy beach to simulate natural environmental conditions. Wave elevations are collected during experiments by two capacitance …

Effects Of Microenvironment On Growth And Differentiation Of Human Dental Pulp Cells, Laura Datko

All Theses

Dental pulp stem cells (DPSCs) have recently been described as a potential stem cell source for various regenerative medicine and tissue engineering applications. They appear to be multipotent, however more characterization is necessary to determine the true potential of these cells. An important aspect of using DPSCs, or any stem cell type, tissue engineering application is the microenvironment within the construct. The microenvironment could include construct mechanical properties, construct composition, and 3D dynamic conditions in vivo. This work aims to study those specific microenvironment effects on DPSCs. To determine the effects of mechanical properties of the substrate on DPSCs, they …

A Quantitative, Technology Independent, Fidelity Metric For Evaluating Bioprinted Patterned Co-Cultures, Matthew Pepper

All Theses

The study of cell-cell interactions is crucial in the understanding of cell behaviors such as tumor genesis, proliferation, migration, metastasis, and apoptosis. To break down the complex web of signals in vivo, researchers must replicate some parts of this environment with in vitro tissue test systems, composed of multiple cell types arranged close enough to communicate with their neighbors, i.e. high-resolution co-culture patterns. The field of bioprinting is specifically focused on creating co-culture patterns for the purposes of cell studies, but the sample resolutions of most bioprinting systems are still too coarse to permit cell communication. No way currently exists …

Aerodynamic Performance Of Extended Formation Flight, Andrew Ning, Tristan Flanzer, Ilan Kroo

Faculty Publications

Close formation flight is of limited practicality for commercial aviation. Our concept of extended formation flight takes advantage of the persistence of cruise wakes by extending the streamwise spacing between aircraft in a formation. This allows the aircraft to fly at safe separation distances from each other, while still benefiting from the upwash of the upstream wake(s). In this paper we are interested in estimating the performance of these extended formations, and estimating some of the effects that limit the longitudinal extent of the formation. We consider the effects of wake rollup, vortex decay, vortex instabilities, vortex motion, and atmospheric …

New Interfacial Nanochemistry On Sensory Bioscaffold-Membranes Of Nanobelts, Feng Chen

Graduate Theses and Dissertations

Nanostructured bioscaffolds and biosensors are evolving as popular and powerful tools in life science and biotechnology, due to the possible control of their surface and structural properties at the nm-scale. Being seldom discussed in literature and long-underexploited in materials and biomedical sciences, development of nanofiber-based sensory bioscaffolds has great promises and grand challenges in finding an ideal platform for low-cost quantifications of biological and chemical species in real-time, label-free, and ultrasensitive fashion. In this study, titanate nanobelts were first of all synthesized, from hydrothermal reactions of a NaOH (or KOH solution) with TiO2 powder, to possess underexploited structure and surface …

Integration Of Ce-Sscp In Genetic Analysis: Fabrication And Optimization Of The Polymer Matrix, Hannah Lintag

Chemical Engineering Undergraduate Honors Theses

Genetic analysis has become an essential aspect in the field of biological research. Genetic material contains an abundance of information that can be harnessed, from the pathological study of diseases to the identification of algal species used for alternative fuel. The detection of genetic species and/or their mutated counterparts is an approach that still warrants improvement, however. Capillary electrophoresis-single strand conformation polymorphism (CE-SSCP) offers a rapid and highly-reproducible means to detect alterations in genetic material. In this project, its implementation in the field of genetic studies as a way to detect mutations in hereditary diseases and identifying species via genetic …

Biodiesel Production From Waste Algae Through Supercritical Methanol And Solid Catalysts, Alexander Lopez

Chemical Engineering Undergraduate Honors Theses

The need for alternate fuels continues to rise as fossil fuel reserves decline, and the effects of harmful fuel emissions on the environment begin to take its toll. One alternate fuel that has great potential is biodiesel. Biodiesel is a non-petroleum based fuel composed of alkyl esters from feedstocks. Using biodiesel as an alternate fuel source has a variety of advantages over traditional petroleum diesel, including producing no SOx emissions and low COx emissions. Another important advantage of biodiesel is that it can be produced from a wide variety of feedstocks. Biodiesel processes using waste cooking oil, animal fats, and …

Nutrient Runoff Following Manure Application, Chance Thayer

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

A field study was completed to measure the effects of varying flow rate on nutrient transport following the application of varying amounts of beef cattle manure to plots containing either no-residue or a wheat residue cover.  Beef cattle manure was applied and incorporated into the soil in May 2010 to meet zero, one, two, four or eight year corn phosphorus requirements. Simulated rainfall events were applied in June and July 2010. The presence of a crop residue cover significantly increased the transport of dissolved phosphorus, total phosphorus, NO₃-N, NH₄-N, and total nitrogen in runoff but decreased …

Decolorization Of An Azo And Anthraquinone Textile Dye By A Mixture Of Living And Non-Living Trametes Versicolor Fungus, Christine M. Dykstra

HIM 1990-2015

Wastewater from the textile industry is difficult to treat effectively due to the prevalent use and wide variety of synthetic dyes that are resistant to conventional treatment methods. White-rot fungi, such as Trametes versicolor, have been found to be effective in decolorizing many of these synthetic dyes and current research is focusing on their application to wastewater treatment. Although numerous studies have been conducted on the ability of both living and nonliving Trametes versicolor to separately decolorize textile dyes, no studies were found to have investigated the use of a mixture of live and dead fungus for decolorization. This study …

Evaluation Of Delivery Conditions For Cutaneous Plasmid Electrotransfer Using A Multielectrode Array, Bernadette Ferraro, Loree C. Heller, Yolmari L. Cruz, Siqi Guo, Amy Donate, Richard Heller

Bioelectrics Publications

Electroporation (EP) is a simple in vivo method to deliver normally impermeable molecules, such as plasmid DNA, to a variety of tissues. Delivery of plasmid DNA by EP to a large surface area is not practical because the distance between the electrode pairs, and therefore the applied voltage, must be increased to effectively permeabilize the cell membrane. The design of the multielectrode array (MEA) incorporates multiple electrode pairs at a fixed distance to allow for delivery of plasmid DNA to the skin, potentially reducing the sensation associated with in vivo EP. In this report, we evaluate the effects of field …

Optical And Raman Characterization Of Ald Alumina Coated Multiwall Carbon Nanotubes And Nanoporous Gold Film, Naod Belai

UNLV Theses, Dissertations, Professional Papers, and Capstones

Due to their large surface to volume ratio nanostructures are inherently unstable. To insure long term stability of nano-devices, they have to be rendered inert to their environment. In this study, nanoporous gold films(NPGF) and multiwall carbon nanotubes were coated with ALD alumina of varying thicknesses. Subsequently, the plasmonic property of the former and electronic property of the latter was monitored by Transmittance and Raman Spectroscopy respectively. Transmittance spectra revealed that NPGF passivated by ALD-alumina maintains its plasmonic properties, i.e. its LSPR supporting properties remained intact. Raman spectra of ALD alumina passivated MWNTs show no coating induced changes in its …

Impacts Of Climate Change And Weather Modification On Hydrologic Characteristics Of Watersheds In The Western United States, Anil Acharya

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research quantifies the impacts of climate change and weather modification (WM) on hydrologic characteristics of watersheds in the arid regions of the western United States. This research performs a long-term simulation of streamflow for present and future climate conditions in the North Platte (NP) Watershed, Wyoming; a shorter duration simulation is then performed to observe the likely impacts of event based changes in an urban watershed in Las Vegas, Nevada.

First, a study is carried out in Chapter 3 that evaluates the impacts of WM on water supply by developing a hydrologic model for the NP Watershed. The variable …

Association Of Oceanic-Atmospheric Oscillations And Hydroclimatic Variables In The Colorado River Basin, Ajay Kalra

UNLV Theses, Dissertations, Professional Papers, and Capstones

With increasing evidence of climatic variability, there is a need to improve forecast for hydroclimatic variables i.e., precipitation and streamflow preserving their spatial and temporal variability. Climatologists have identified different oceanic-atmospheric oscillations that seem to influence the behavior of these variables and in turn can be used to extend the forecast lead time. In the absence of a good physical understanding of the linkages between oceanic-atmospheric oscillations and hydrological processes, it is difficult to construct a physical model. An attractive alternative to physically based models are the Artificial Intelligence (AI) type models, also referred to as machine learning or data-driven …

Modification Of Pathways With Pseudomonas For The Extraction And Subsequent Conversion Of Algae To Butanol, Danielle Frechette

Biological and Agricultural Engineering Undergraduate Honors Theses

As the demand for alternative fuels steadily increases, algae continue to be an excellent source for the development of biofuels. While algae have exhibited substantial potential for butanol production, there are limitations when it comes to the extraction process-its inability to withdraw oils and sugars usable for fermentation from cell walls. The genes of two bacteria were combined, creating a new organism that can both extract sugars and oils from algal cell walls and create butanol, simplifying the fermentation process while increasing efficiency. Pseudomonas flourescens, an obligate aerobe, has been shown in literature to degrade these cell walls to make …

Generation Of Human Ips Cells Using Direct Reprogramming Proteins, Nick Blazic

Biological and Agricultural Engineering Undergraduate Honors Theses

Human induced pluripotent stem (hiPS) cells present the opportunity to advance tissue engineering and regenerative medicine for treating many diseases such as diabetes, Parkinson’s disease, spinal cord injury, and cancer. In recent years, stem cell research has made progress in advancing cell therapy techniques. Similar to human embryonic stem (hES) cells, hiPS cells can differentiate into the three germ layers, which include mesorderm, ectoderm, and endoderm. Thus, they have the potential of being differentiated into all types of cells that are required for tissue repair and regeneration. The advantage that hiPS cells have over hES cells is that they can …

Development Of An Inverse Liquid Chromatographic Technique To Measure Adsorption Of Amino Acid Sorbates Onto Chitosan, Yamama Hafeez

Biological and Agricultural Engineering Undergraduate Honors Theses

Drug delivery is described as the localized sustained delivery of a pharmaceutical agent to the systemic blood circulation and hence to the site of action to produce a desired pharmacological effect [1]. There are three principle ways of drug delivery, first being the injection of the drug loaded on microspheres in this method of drug delivery, microspheres are formed using a combination of ink-jet technology and single emulsion-solvent evaporation techniques. Microspheres of a certain size are produced such as to administer the desired route of administration and the rate of the drug release [1]. Another form of drug delivery commonly …

Enhancing The Differentiation Efficiency Of Human Embryonic Stem Cells Into Insulin-Secreting β-Cells, Katherine Rutledge

Biological and Agricultural Engineering Undergraduate Honors Theses

Recent studies have shown that human embryonic stem cells possess the ability to differentiate into almost any cell type in the bod and they can self-renew in culture conditions (Baetge, D'Amour et al. 26). As the number of Americans with Type 1 Diabetes continues to increase, innovative methods of treating this chronic illness must be developed in order to improve the quality of life for the affected individuals. Human embryonic stem cells (hESCs) have shown the potential to differentiate successfully into insulin-secreting β-cells, and these cultured β-cells can be used for cell-treatment therapies to replace the deficient β-cells in diabetes …

Cost Efficient Method Of Pumping Water For Small, Remote Rural Communities, James Hudson

Chemical Engineering Undergraduate Honors Theses

Many technologies are used for water disinfection. Chlorine, iodine, and ozone are some chemical methods of water disinfection. Filtration, including microfiltration, ultrafiltration, and reverse osmosis, is used to remove bacteria. In addition to chemical and filtration technologies, one can disinfect water using UV irradiation, ultrasonic treatment, electrolysis, solar disinfection, and slow sand filtration.
Currently, there are few solutions being employed in third world settings for communities. The current solutions are either for one household or are part of an existing infrastructure and therefore are not portable. Slow sand filtration is used successfully to provide potable water for individual households. Tablet …

Application Of Nanotechnology For Targeted Delivery Of Antibacterial Enzymes And For Enzyme-Based Coatings On Medical Devices And Implants, Rohan Satishkumar

All Dissertations

The frequency of S. aureus infection and subsequent biofilm formation associated with vascular catheterization has been increasing in recent years and often begins as a local colonization at the site of the catheter insertion. Antimicrobial enzymes and peptides, which are effective against a broad range of pathogens and low rates of resistance, have attracted attention as promising alternative candidates in treatment of infections caused by antibiotic resistant bacteria. The use of nanoparticles as carriers for enzymes, in addition to their size, charge, high surface area per volume etc. offers targeted delivery of enzymes to pathogenic bacteria. We proposed to use …