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Full-Text Articles in Engineering

Effects Of Air-Injection Pressure On Airflow Pattern Of Air Sparging, Arvin Farid, Atena Najafi, Jim Browning, Elisa Barney Smith Oct 2021

Effects Of Air-Injection Pressure On Airflow Pattern Of Air Sparging, Arvin Farid, Atena Najafi, Jim Browning, Elisa Barney Smith

Civil Engineering Faculty Publications and Presentations

Air sparging is a remediation technology for treating soil/groundwater contaminated with volatile organic compounds (VOCs). VOC removal during air sparging is rendered less effective because of the random formation of air channels, creating preferential paths for airflow, thus limiting remediation to these channels, referred to as a zone of influence (ZOI). Pulsation is a popular method used to improve the effectiveness of air sparging through cyclic operation, with the hope that air channels would form elsewhere. Pulsation makes air sparging more time-consuming. This paper studies the effects of one cycle of pulsation and air pressure on the airflow pattern and …


Excited-State Lifetimes Of Dna-Templated Cyanine Dimer, Trimer, And Tetramer Aggregates: The Role Of Exciton Delocalization, Dye Separation, And Dna Heterogeneity, Jonathan S. Huff, Daniel B. Turner, Olga A. Mass, Lance K. Patten, Christopher K. Wilson, Simon K. Roy, Matthew S. Barclay, Bernard Yurke, William B. Knowlton, Paul H. Davis, Ryan D. Pensack Sep 2021

Excited-State Lifetimes Of Dna-Templated Cyanine Dimer, Trimer, And Tetramer Aggregates: The Role Of Exciton Delocalization, Dye Separation, And Dna Heterogeneity, Jonathan S. Huff, Daniel B. Turner, Olga A. Mass, Lance K. Patten, Christopher K. Wilson, Simon K. Roy, Matthew S. Barclay, Bernard Yurke, William B. Knowlton, Paul H. Davis, Ryan D. Pensack

Materials Science and Engineering Faculty Publications and Presentations

DNA-templated molecular (dye) aggregates are a novel class of materials that have garnered attention in a broad range of areas including light harvesting, sensing, and computing. Using DNA to template dye aggregation is attractive due to the relative ease with which DNA nanostructures can be assembled in solution, the diverse array of nanostructures that can be assembled, and the ability to precisely position dyes to within a few Angstroms of one another. These factors, combined with the programmability of DNA, raise the prospect of designer materials custom tailored for specific applications. Although considerable progress has been made in characterizing the …


First-Principles Studies Of Substituent Effects On Squaraine Dyes, German Barcenas, Austin Biaggne, Olga A. Mass, Christopher K. Wilson, Ryan D. Pensack, Jeunghoon Lee, William B. Knowlton, Bernard Yurke, Lan Li May 2021

First-Principles Studies Of Substituent Effects On Squaraine Dyes, German Barcenas, Austin Biaggne, Olga A. Mass, Christopher K. Wilson, Ryan D. Pensack, Jeunghoon Lee, William B. Knowlton, Bernard Yurke, Lan Li

Materials Science and Engineering Faculty Publications and Presentations

Dye molecules that absorb light in the visible region are key components in many applications, including organic photovoltaics, biological fluorescent labeling, super-resolution microscopy, and energy transport. One family of dyes, known as squaraines, has received considerable attention recently due to their favorable electronic and photophysical properties. In addition, these dyes have a strong propensity for aggregation, which results in emergent materials properties, such as exciton delocalization. This will be of benefit in charge separation and energy transport along with fundamental studies in quantum information. Given the high structural tunability of squaraine dyes, it is possible that exciton delocalization could be …


An Alternative Approach To Nucleic Acid Memory, George D. Dickinson, Golam Md Mortuza, William Clay, Luca Piantanida, Christopher M. Green, Chad Watson, Eric J. Hayden, Tim Andersen, Wan Kuang, Elton Graugnard, Reza Zadegan, William L. Hughes Apr 2021

An Alternative Approach To Nucleic Acid Memory, George D. Dickinson, Golam Md Mortuza, William Clay, Luca Piantanida, Christopher M. Green, Chad Watson, Eric J. Hayden, Tim Andersen, Wan Kuang, Elton Graugnard, Reza Zadegan, William L. Hughes

Materials Science and Engineering Faculty Publications and Presentations

DNA is a compelling alternative to non-volatile information storage technologies due to its information density, stability, and energy efficiency. Previous studies have used artificially synthesized DNA to store data and automated next-generation sequencing to read it back. Here, we report digital Nucleic Acid Memory (dNAM) for applications that require a limited amount of data to have high information density, redundancy, and copy number. In dNAM, data is encoded by selecting combinations of single-stranded DNA with (1) or without (0) docking-site domains. When self-assembled with scaffold DNA, staple strands form DNA origami breadboards. Information encoded into the breadboards is read by …


Substituent Effects On The Solubility And Electronic Properties Of The Cyanine Dye Cy5: Density Functional And Time-Dependent Density Functional Theory Calculations, Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li Feb 2021

Substituent Effects On The Solubility And Electronic Properties Of The Cyanine Dye Cy5: Density Functional And Time-Dependent Density Functional Theory Calculations, Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li

Materials Science and Engineering Faculty Publications and Presentations

The aggregation ability and exciton dynamics of dyes are largely affected by properties of the dye monomers. To facilitate aggregation and improve excitonic function, dyes can be engineered with substituents to exhibit optimal key properties, such as hydrophobicity, static dipole moment differences, and transition dipole moments. To determine how electron donating (D) and electron withdrawing (W) substituents impact the solvation, static dipole moments, and transition dipole moments of the pentamethine indocyanine dye Cy5, density functional theory (DFT) and time-dependent (TD-) DFT calculations were performed. The inclusion of substituents had large effects on the solvation energy of Cy5, with pairs of …


Design And Implementation Of Fully Integrated Cmos On-Chip Bandpass Filter With Wideband High-Gain Low Noise Amplifier, Yu Wang Jan 2021

Design And Implementation Of Fully Integrated Cmos On-Chip Bandpass Filter With Wideband High-Gain Low Noise Amplifier, Yu Wang

Browse all Theses and Dissertations

Current trends of fully integrated CMOS on-chip bandpass filter are classified into 1) the component level (i.e., active inductor, Q-enhanced passive inductor, negative resistance cancellation), and 2) the circuit level (i.e., adding transmission zeros on stopband, applying the zigzag technique for fewer inductors, superposition of different resonators). The demand for monolithic designs for portable devices attracts market interest in a fully integrated CMOS on-chip bandpass filter. Optimized minimal inductors (OMI) bandpass filter is a good platform for use in both active and passive bandpass filters, mainly because 1) it provides good stopband rejection for high interface attenuation, and 2) the …


The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer Jan 2021

The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer

Browse all Theses and Dissertations

A new method for analyzing the effectiveness of NMR impulse power amplifiers was developed using a classical linear systems approach to NMR. The method demonstrates a way to compare NMR power amplifiers and outputs. Thermodynamic calculations and the harmonic content of NMR amplifiers is presented to provide a complete description of the NMR power amplifier design problem. A design procedure for class E NMR power amplifiers with a pi-impedance matching network is outlined for matching the amplifier to the transmitter coil. The thesis concludes with the presentation of a 53 MHz power amplifier developed with the procedure. The complete amplifier …


Interferometry Analysis Method For Colliding Plasma Generated With Exploded Wires, Michael D. Gruesbeck Jan 2021

Interferometry Analysis Method For Colliding Plasma Generated With Exploded Wires, Michael D. Gruesbeck

Browse all Theses and Dissertations

Building upon recent work to estimate electron and ion densities from paired interferograms, the current work develops a model for the 2D interference phase function. Unlike the previous work that only estimated a radial plasma profile from images of a singly exploded straight Cu wire, we estimate 2D properties from a colliding plasma generated from two simultaneously exploded wires. First, a 2D phase model is proposed for the interference patterns of the images taken at 1064 nm and 532 nm. Then, the model parameters are estimated using Fourier analysis. Secondly, the plasma region in each image is partitioned into subregions …


Hardware Security And Side Channel Power Analysis For 16x16 Booth Multiplier In 65nm Cmos Technology, Kanchan Vissamsetty Jan 2021

Hardware Security And Side Channel Power Analysis For 16x16 Booth Multiplier In 65nm Cmos Technology, Kanchan Vissamsetty

Browse all Theses and Dissertations

As feature size is scaling down, dynamic power consumption reduces but static power consumption increases. Due to the increase of static power, leakage currents as a source, the information can be exploited successfully as a side-channel to recover the secrets of the cryptographic implementations. An attacker who has access to the hardware fabrication can insert a Trojan to the design to steal or alter information. In this thesis, a post-fab static voltage variation/detection technique is developed to detect the potential fabrication process Trojan insertion. The technique is, dividing the designed circuit into N equal segments, where each segment would have …


Deep Learning For Compressive Sar Imaging With Train-Test Discrepancy, Morgan R. Mccamey Jan 2021

Deep Learning For Compressive Sar Imaging With Train-Test Discrepancy, Morgan R. Mccamey

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We consider the problem of compressive synthetic aperture radar (SAR) imaging with the goal of reconstructing SAR imagery in the presence of under sampled phase history. While this problem is typically considered in compressive sensing (CS) literature, we consider a variety of deep learning approaches where a deep neural network (DNN) is trained to form SAR imagery from limited data. At the cost of computationally intensive offline training, on-line test-time DNN-SAR has demonstrated orders of magnitude faster reconstruction than standard CS algorithms. A limitation of the DNN approach is that any change to the operating conditions necessitates a costly retraining …


Reconfigurable Antenna Array Using The Pin-Diode-Switched Printed Square Spiral Element, Corey M. Stamper Jan 2021

Reconfigurable Antenna Array Using The Pin-Diode-Switched Printed Square Spiral Element, Corey M. Stamper

Browse all Theses and Dissertations

A dual-band array of reconfigurable elements is modeled and simulated. The array consists of four single square spiral microstrip antennas that are corporately fed and are used as a unit cell. The single square spiral uses two PIN diodes as switching elements to achieve reconfiguration. The array has four switch states that can operate over four discrete frequencies in the S and C bands. The unit cell radiation pattern is used with the pattern multiplication model to quickly simulate the array pattern of larger arrays. A 3 x 3 array of the unit cells is modeled with only the center …


The Effect Of Winding Curvature And Core Permeability On The Power Losses And Leakage Inductance Of High-Frequency Transformers, Daniel J. Whitman Jan 2021

The Effect Of Winding Curvature And Core Permeability On The Power Losses And Leakage Inductance Of High-Frequency Transformers, Daniel J. Whitman

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At the frequencies used in switching dc-dc converters, the skin and proximity effects have a significant effect on both the losses and leakage inductance of the transformers used in these circuits. Analytical expressions that have been derived to calculate ac resistance and leakage inductance have primarily used a 1-D approximation. They also have used Cartesian coordinates or approximations that are equivalent to Cartesian coordinates, as well as usually assuming an ideal core of infinite permeability. The classical result in the case of the resistance/losses is Dowell’s equation, and there are analogous results for leakage inductance. This dissertation derives new equations …