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Nigella Sativa Methanol Extract Inhibits Pc-3 Cell Line Colonization, Induced Apoptosis, And Modulated Lc3-Based Autophagy, Yusuf Toy, Merve Kivrik, Marwa H. Alkhafaji, Aryan M. Faraj, Ibrahim H. Gecibesler, Can A. Ağca May 2022

Nigella Sativa Methanol Extract Inhibits Pc-3 Cell Line Colonization, Induced Apoptosis, And Modulated Lc3-Based Autophagy, Yusuf Toy, Merve Kivrik, Marwa H. Alkhafaji, Aryan M. Faraj, Ibrahim H. Gecibesler, Can A. Ağca

Karbala International Journal of Modern Science

Nigella sativa has various pharmacological properties and has been used throughout history for a variety of reasons. However, there is limited data about the effects of Nigella sativa (NS) on human cancer cells. This study aimed at observing the roles of methanolic extract of N. sativa on apoptosis and autophagy pathway in the Human PC3 (prostate cancer) cell line. The cell viability was checked by MTT assay. Clonogenic assay was performed to demonstrate clonogenicity and Western blot was used to check caspase-3, TIGAR, p53, and LC3 protein expression. The results demonstrated that PC3 cell proliferation was inhibited, caspase-3 and p53 …


Ultrasound-Assisted Dibutyl Phthalate Nanocapsules Preparation And Its Application As Corrosion Inhibition Coatings, Uday Bagale, Ammar Kadi, Irina Potoroko, Vinay Rangari, Minakshi Mahale May 2022

Ultrasound-Assisted Dibutyl Phthalate Nanocapsules Preparation And Its Application As Corrosion Inhibition Coatings, Uday Bagale, Ammar Kadi, Irina Potoroko, Vinay Rangari, Minakshi Mahale

Karbala International Journal of Modern Science

The current research employs an encapsulation of dibutyl phthalate (DBP) as a corrosion inhibitor in situ polymerization using a sonochemical method to form nanocapsules. The prepared nanocapsules were characterization by using Malvern particle size, Fouri-er transforms infrared spectroscopy (FTIR), Scanning electron microscope (SEM) and Transmission electron microscope (TEM), and thermal and mechanical test to check particle size, morphology, and stability of nanocapsules. Later prepared DBP nanocapsules were incorporated in standard epoxy coating to check its corrosion inhibition resistance. The results show that nanocapsules are spherical, with an average particle size of 337 nm. Scratch nanocapsules epoxy coating shows improves coating …


Heterogeneous Catalytic Degradation Of Dye By Fenton-Like Oxidation Over A Continuous System Based On Box–Behnken Design And Traditional Batch Experiments, Imad M. Luaibi, Mohammed A. Atiya, Ahmed K. Hassan, Zainab A. Mahmoud May 2022

Heterogeneous Catalytic Degradation Of Dye By Fenton-Like Oxidation Over A Continuous System Based On Box–Behnken Design And Traditional Batch Experiments, Imad M. Luaibi, Mohammed A. Atiya, Ahmed K. Hassan, Zainab A. Mahmoud

Karbala International Journal of Modern Science

In this study, iron was coupled with copper to form a bimetallic compound through a biosynthetic method, which was then used as a catalyst in the Fenton-like processes for removing direct Blue 15 dye (DB15) from aqueous solution. Characterization techniques were applied on the resultant nanoparticles such as SEM, BET, EDAX, FT-IR, XRD, and zeta potential. Specifically, the rounded and shaped as spherical nanoparticles were found for green synthesized iron/copper nanoparticles (G-Fe/Cu NPs) with the size ranging from 32-59 nm, and the surface area was 4.452 m2/g. The effect of different experimental factors was studied in both batch and continuous …


Optical Measurement And Performance Prediction Of Solar Pv System In Al-Khidhir Zone/Iraq, Faten Sh. Zainulabdeen, Jaber O. Dahloos, Ahmed F. Atwan, Naseer K. Kasim May 2022

Optical Measurement And Performance Prediction Of Solar Pv System In Al-Khidhir Zone/Iraq, Faten Sh. Zainulabdeen, Jaber O. Dahloos, Ahmed F. Atwan, Naseer K. Kasim

Karbala International Journal of Modern Science

People have tended for investing the sources of renewable energy, especially solar energy, as they are clean and environmentally friendly sources. The present work aims to invest the measured data of solar irradiance, maximum ambient temperatures and wind speed provided by Al Khidhir Meteorological Station to predict the minimum performance of photovoltaic solar systems (NT-R0E3E-SHARP) for electric power generation. The single diode model is used to calculate the minimum output power produced by solar module and its minimum conversion efficiency based on soalr irradiance, maximum ambient temperatures and wind speed throughout 2020. The results indicate that the annual solar irradiance …


Monte Carlo Study Of Lepton Flavor Universality Violation In B Decays With Belle Ii Simulation, Sakul Mahat May 2022

Monte Carlo Study Of Lepton Flavor Universality Violation In B Decays With Belle Ii Simulation, Sakul Mahat

Honors Theses

Belle II, the first super B-Factory experiment, is designed to make precise measurements of weak interaction parameters and search for New Physics beyond the Standard Model of particle physics. The Standard Model of particle physics is a theory that classifies all known elementary particles and describes three of the four known fundamental forces in the universe. Physics beyond the Standard Model that addresses the theoretical developments needed to explain the deficiencies in the Standard Model is often referred to as New Physics. One of the assumptions of the Standard Model is that the couplings of particles that mediate the weak …


Approaching Quantum-Limited Electrometry In The Single-Photon Regime, Sisira Kanhirathingal May 2022

Approaching Quantum-Limited Electrometry In The Single-Photon Regime, Sisira Kanhirathingal

Dartmouth College Ph.D Dissertations

Mesoscopic quantum systems currently serve as essential building blocks in many quantum information and metrology devices. This thesis investigates the potential of quantum-limited detection in a mesoscopic electrometer named the cavity-embedded Cooper pair transistor (cCPT). As one application, this charge detector can act as the basis for an optomechanical system in the single-photon strong coupling regime. The realization of this scheme would entail near quantum-limited, ultra-sensitive electrometry at the single-photon level, the feasibility of which is studied at length in this thesis.

On the one hand, we approach this question using a fundamental, first-principles study, where an operator scattering model …


Surface Plasmon Characterization In Ag Nanotriangles For Evaluation Of Fano Resonance Conditions, Nabila Islam May 2022

Surface Plasmon Characterization In Ag Nanotriangles For Evaluation Of Fano Resonance Conditions, Nabila Islam

Student Research Symposium

Surface plasmon polariton (SPP) is a collective oscillation of electrons and light at the metal -dielectric interface excited by the incident radiation on metal surface through the momentum matching conditions. The properties of SPPs and the resonance conditions are highly dependent on the confining materials and geometry of the confining nanostructure. The sensitivity of the surface plasmon resonance to the property of the confining materials made Surface plasmon resonance (SPR) sensors a central tool for biosensing. However, the frequency resolution of SPR sensors is typically limited by the broad resonance of the SPR mode. The resolution can be enhanced through …


Using Digital Holographic Microscopy To Characterize Vibrio's Chemotaxis, Jacqueline Acres, Eric Valentino May 2022

Using Digital Holographic Microscopy To Characterize Vibrio's Chemotaxis, Jacqueline Acres, Eric Valentino

Student Research Symposium

Vibrio alginolyticus is a marine bacterium that displays distinctive chemotactic behavior. Chemotaxis is the ability to move in response to a concentration gradient, either in the direction of nutrients or away from repellants. Vibrio's single, polar flagellum allows it to form a tight cloud in the presence of a chemoattractant. In this work, we experimentally characterize cloud sizes after both normal culture conditions and simulated microgravity using digital holographic microscopy or DHM. DHM allows visualization of volumetric samples by recording x,y,z and t information in holograms. Plane-by-plane reconstruction retrieves the z-plane information which can then by stitched together into hyperstacks …


Stabilization Of Phenanthrene Anions In Helium Nanodroplets, Siegfried Kollotzek, Farhad Izadi, Miriam Meyer, Stefan Bergmeister, Fabio Zappa, Stephan Denifl, Olof E. Echt, Paul Scheier, Elisabeth Gruber May 2022

Stabilization Of Phenanthrene Anions In Helium Nanodroplets, Siegfried Kollotzek, Farhad Izadi, Miriam Meyer, Stefan Bergmeister, Fabio Zappa, Stephan Denifl, Olof E. Echt, Paul Scheier, Elisabeth Gruber

Faculty Publications

It has been debated for years if the polycyclic aromatic hydrocarbon phenanthrene exists in its anionic form, or, in other words, if its electron affinity (EA) is positive or negative. In this contribution we confirm that the bare phenanthrene anion Ph- created in a binary collision with an electron at room temperature has a lifetime shorter than microseconds. However, the embedding of neutral phenanthrene molecules in negatively charged helium nanodroplets enables the formation of phenanthrene anions by charge transfer processes and the stabilization of the latter in the ultracold environment. Gentle shrinking of the helium matrix of phenanthrene-doped HNDs …


Search For Higgsinos Decaying To Two Higgs Bosons And Missing Transverse Momentum In Proton-Proton Collisions At √S = 13 Tev, A. Tumasyan May 2022

Search For Higgsinos Decaying To Two Higgs Bosons And Missing Transverse Momentum In Proton-Proton Collisions At √S = 13 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

Results are presented from a search for physics beyond the standard model in proton-proton collisions at √s = 13TeV in channels with two Higgs bosons, each decaying via the process H ⟶ b[], and large missing transverse momentum. The search uses a data sample corresponding to an integrated luminosity of 137 fb−1 collected by the CMS experiment at the CERN LHC. The search is motivated by models of supersymmetry that predict the production of neutralinos, the neutral partners of the electroweak gauge and Higgs bosons. The observed event yields in the signal regions are found to be consistent with …


The Lick Agn Monitoring Project 2016: Dynamical Modeling Of Velocity-Resolved Hβ Lags In Luminous Seyfert Galaxies, Lizvette Villafaña, Peter R. Williams, Tommaso Treu, Brendon J. Brewer, Aaron J. Barth, Vivian U, Vardha N. Bennert, H. Alexander Vogler, Hengxiao Guo, Misty C. Bentz May 2022

The Lick Agn Monitoring Project 2016: Dynamical Modeling Of Velocity-Resolved Hβ Lags In Luminous Seyfert Galaxies, Lizvette Villafaña, Peter R. Williams, Tommaso Treu, Brendon J. Brewer, Aaron J. Barth, Vivian U, Vardha N. Bennert, H. Alexander Vogler, Hengxiao Guo, Misty C. Bentz

Physics

We have modeled the velocity-resolved reverberation response of the Hβ broad emission line in nine Seyfert 1 galaxies from the Lick Active Galactic Nucleus (AGN) Monitoring Project 2016 sample, drawing inferences on the geometry and structure of the low-ionization broad-line region (BLR) and the mass of the central supermassive black hole. Overall, we find that the Hβ BLR is generally a thick disk viewed at low to moderate inclination angles. We combine our sample with prior studies and investigate line-profile shape dependence, such as log₁₀(FWHM/σ), on BLR structure and kinematics and search for any BLR luminosity-dependent trends. We …


Hinged Temperature-Immune Self-Referencing Fabry–Pérot Cavity Sensors, Jeremiah C. Williams, Hengky Chandrahalim May 2022

Hinged Temperature-Immune Self-Referencing Fabry–Pérot Cavity Sensors, Jeremiah C. Williams, Hengky Chandrahalim

AFIT Patents

A passive microscopic Fabry-Pérot Interferometer (FPI) sensor includes a three-dimensional microscopic optical structure formed on a cleaved tip of the optical fighter using a two-photon polymerization process on a photosensitive polymer by a three-dimensional micromachining device. The three-dimensional microscopic optical structure having a hinged optical layer pivotally connected to a distal portion of a suspended structure. A reflective layer is deposited on a mirror surface of the hinged optical layer while in an open position. The hinged optical layer is subsequently positioned in the closed position to align the mirror surface to at least partially reflect a light signal back …


Particle-In-Cell Simulations Of Ion Dynamics In A Pinched-Beam Diode, Jesse C. Foster, John W. Mcclory, S. B. B. Swanekamp, D. D. Hinshelwood, A. S. Richardson, Paul E. Adamson, J. W. Schumer, R. W. James, P. F. Ottinger, D. Mosher May 2022

Particle-In-Cell Simulations Of Ion Dynamics In A Pinched-Beam Diode, Jesse C. Foster, John W. Mcclory, S. B. B. Swanekamp, D. D. Hinshelwood, A. S. Richardson, Paul E. Adamson, J. W. Schumer, R. W. James, P. F. Ottinger, D. Mosher

Faculty Publications

article-in-cell simulations of a 1.6 MV, 800 kA, and 50 ns pinched-beam diode have been completed with emphasis placed on the quality of the ion beams produced. Simulations show the formation of multiple regions in the electron beam flow characterized by locally high charge and current density (“hot spots”). As ions flow through the electron-space-charge cloud, these hot spots electrostatically attract ions to produce a non-uniform ion current distribution. The length of the cavity extending beyond the anode-to-cathode gap (i.e., behind the cathode tip) influences both the number and amplitude of hot spots. A longer cavity length increases the number …


Search For Heavy Resonances Decaying To A Pair Of Lorentz-Boosted Higgs Bosons In Final States With Leptons And A Bottom Quark Pair At √S = 13 Tev, A. Tumasyan May 2022

Search For Heavy Resonances Decaying To A Pair Of Lorentz-Boosted Higgs Bosons In Final States With Leptons And A Bottom Quark Pair At √S = 13 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

A search for new heavy resonances decaying to a pair of Higgs bosons (HH) in proton-proton collisions at a center-of-mass energy of 13TeV is presented. Data were collected with the CMS detector at the LHC in 2016–2018, corresponding to an integrated luminosity of 138 fb−1. Resonances with a mass between 0.8 and 4.5TeV are considered using events in which one Higgs boson decays into a bottom quark pair and the other into final states with either one or two charged leptons. Specifically, the single-lepton decay channel HH ⟶ b[]WW* ⟶ b[]ℓvq[]' and the dilepton decay channels HH ⟶ …


Optical Vortex Generation Using 3-D Printed Reflection And Transmission Holograms, Tara R. Crowe May 2022

Optical Vortex Generation Using 3-D Printed Reflection And Transmission Holograms, Tara R. Crowe

Honors Capstone Projects and Theses

No abstract provided.


Seasonal Variations In Global Ionospheric Total Electron Content, Jason Knudsen May 2022

Seasonal Variations In Global Ionospheric Total Electron Content, Jason Knudsen

Physics Capstone Projects

As the Sun ionizes atoms and molecules in the Earth’s ionosphere, the region of atmosphere above approximately 100 km in altitude, the created ionization in this region affects many of the systems that we rely on in daily life. This includes cellular service, GPS navigation, weather forecasting, and credit card data. A good measure for the level of ionization in the ionosphere is total electron content (TEC), which is the number of electrons in a square column above a given geographic location. The TEC over a geographic location influences the propagation of radio waves that traverse that section of the …


Hhl Algorithm On The Honeywell H1 Quantum Computer, Adrik B. Herbert, Eric A. F. Reinhardt May 2022

Hhl Algorithm On The Honeywell H1 Quantum Computer, Adrik B. Herbert, Eric A. F. Reinhardt

Discovery Undergraduate Interdisciplinary Research Internship

The quantum algorithm for linear systems of equations (HHL algorithm) provides an efficient tool for finding solutions to systems of functions with a large number of variables and low sensitivity to changes in inputs (i.e. low error rates). For complex problems, such as matrix inversion, HHL requires exponentially less computational time as compared with classical computation methods. HHL can be adapted to current quantum computing systems with limited numbers of qubits (quantum computation bits) but a high reusability rate such as the Honeywell H1 quantum computer. Some methods for improving HHL have been proposed through the combination of quantum and …


Aloso: Spectroscopy And Structure Of A New Group Of Astrochemical Molecules, Vincent J. Esposito, Tarek Trabelsi, Joseph S. Francisco May 2022

Aloso: Spectroscopy And Structure Of A New Group Of Astrochemical Molecules, Vincent J. Esposito, Tarek Trabelsi, Joseph S. Francisco

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

No abstract provided.


Nessie Notation: A New Tool In Sequential Substitution Systems And Graph Theory For Summarizing Concatenations, Colton Davis May 2022

Nessie Notation: A New Tool In Sequential Substitution Systems And Graph Theory For Summarizing Concatenations, Colton Davis

Student Research

While doing research looking for ways to categorize causal networks generated by Sequential Substitution Systems, I created a new notation to compactly summarize concatenations of integers or strings of integers, including infinite sequences of these, in the same way that sums, products, and unions of sets can be summarized. Using my method, any sequence of integers or strings of integers with a closed-form iterative pattern can be compactly summarized in just one line of mathematical notation, including graphs generated by Sequential Substitution Systems, many Primitive Pythagorean Triplets, and various Lucas sequences including the Fibonacci sequence and the sequence of square …


Synthesis, Characterization, And Functionality Of Novel 2d Material Sn3p2, Cory Stephenson May 2022

Synthesis, Characterization, And Functionality Of Novel 2d Material Sn3p2, Cory Stephenson

Physics Undergraduate Honors Theses

In recent years, two-dimensional (2D) materials have gained a lot of attention due to their potential applications in devices and their promise to revolutionize technology. In our group, we are capable of synthesizing such materials and study their properties. I have discovered a new material of the tin-phosphorus family that displays the 2D layered structure and therefore shows potential to be used in future devices due to this reduced dimensionality from the typical three-dimensional counterpart. This 2D structure may allow for new phenomena to emerge as there is no longer any interatomic interactions along the z- axis. Under this motivation, …


Characteristics Of Mesospheric Temperature And Gravity Waves Over Chile In 2020-2021, Damien M. Devitt, Kenneth Zia May 2022

Characteristics Of Mesospheric Temperature And Gravity Waves Over Chile In 2020-2021, Damien M. Devitt, Kenneth Zia

Physics Capstone Projects

Gravity waves (GWs) are often confused with gravitational waves in the fabric of space time. However, there is a clear distinction between them. Gravity wave is a term used by the atmospheric research field to describe perturbations in the atmosphere. Gravity pulls the perturbations down and causes oscillations, these present in the form of waves. The best visualization is to think of ripples on a pond, as the ripple reaches its peak gravity pulls the ripple down and creates an oscillating effect.


Thermal Expansion And Phonon Anharmonicity Of Cuprite Studied By Inelastic Neutron Scattering And Ab Initio Calculations, C. N. Saunders, D. S. Kim, O. Hellman, Hillary L. Smith, N. J. Weadock, S. T. Omelchenko, G. E. Ganroth, C. M. Bernal-Choban, S. H. Lohaus, D. L. Abernathy, B. Fultz May 2022

Thermal Expansion And Phonon Anharmonicity Of Cuprite Studied By Inelastic Neutron Scattering And Ab Initio Calculations, C. N. Saunders, D. S. Kim, O. Hellman, Hillary L. Smith, N. J. Weadock, S. T. Omelchenko, G. E. Ganroth, C. M. Bernal-Choban, S. H. Lohaus, D. L. Abernathy, B. Fultz

Physics & Astronomy Faculty Works

Inelastic neutron scattering measurements were performed with a time-of-flight chopper spectrometer to observe phonons in all parts of the Brillouin zone of a single crystal of cuprite Cu₂ O. We reduced the experimental data to phonon dispersions in the high-symmetry directions, and changes between 10 and 300 K are reported. In this paper, we show ab initio quasiharmonic (QH) and anharmonic (AH) calculations of phonon dispersions. We performed all AH calculations with a temperature-dependent effective potential method. Both QH and AH calculations account for the small negative thermal expansion of cuprite at low temperatures. However, the measured temperature-dependent phonon behavior …


Ongoing Calculus In The Cerebral Cortex, Luke Long May 2022

Ongoing Calculus In The Cerebral Cortex, Luke Long

Physics Undergraduate Honors Theses

Various modes of neuronal computations have long been theorized to be possible based on the structure and geometry of the brain. These computations also seem necessary for many of the integral functions of the brain, like information processing and regulatory processes in the body. However, experimental data directly supporting these claims have been rare.

In this study, data collected in mice from a large number of neurons over a long period of time provided the opportunity to search for some of these computations, specifically change detection and squaring calculations. Using Matlab, the goal of this analysis was to find statistically …


Stem Club, Camden Jones, Erica Gesner, Amber Gadeken May 2022

Stem Club, Camden Jones, Erica Gesner, Amber Gadeken

Honors Program: Expanded Learning Clubs

The goal of this club is to introduce various topics stemming from different fields in science. We hope to excite the students about science and show them how important it is to their everyday lives. This club also aims to provide free education to underserved communities.


Scale-Free Behavioral Dynamics Directly Linked With Scale-Free Cortical Dynamics, Sabrina Jones May 2022

Scale-Free Behavioral Dynamics Directly Linked With Scale-Free Cortical Dynamics, Sabrina Jones

Physics Undergraduate Honors Theses

In organisms, an interesting phenomenon occurs in both behavior and neuronal activity: organization with fractal, scale-free fluctuations over multiple spatiotemporal orders of magnitude (1,2). In regard to behavior, this sort of complex structure-- which manifests itself from small scale fidgeting to purposeful, full body movements-- may support goals such as foraging (3-6), visual search (4), and decision making (7,8). Likewise, the presence of this sort of structure in the cerebral cortex in the form of spatiotemporal cascades, coined “neuronal avalanches,” may offer optimal information transfer (9). Thus, when considering the functional relationship between the cerebral cortex and movements of the …


Emergent Spectra Of Young X-Ray Emitting Populations Across Environments, Alex Siebenmorgen May 2022

Emergent Spectra Of Young X-Ray Emitting Populations Across Environments, Alex Siebenmorgen

Physics Undergraduate Honors Theses

We construct reasonably accurate models of the X-Ray spectra of a multitude of sources in M51. We construct both average and individual models for the sources, which are split into 16 groups as the counts per source increases. Then, we create a plot to show how the model-predicted values of column density (nH) and photon index (gamma) change with luminosity. These models will be used to create an accurate X-Ray stellar energy distribution (SED) for M51, and to better understand how the SED changes with environmental factors like metallicity and star formation rate (SFR).


Generation & Kinetic Studies Of Porphyrin Chromium-Oxo Intermediates, Iyanu Olumide Ojo May 2022

Generation & Kinetic Studies Of Porphyrin Chromium-Oxo Intermediates, Iyanu Olumide Ojo

Masters Theses & Specialist Projects

Recent emerging applications of chromium porphyrin complexes are generating increasing interest in oxidation chemistry and catalysis. Its recent application as metal-organic frames in spintronic devices supports the rich electronic system of chromium metal. Through the past decades, first-row transition metalloporphyrins have served as biomimetic oxidation catalysts and models of cytochrome P450 enzymes. However, the oxygen atom transfer mechanism of chromium porphyrin complexes, most especially in sulfide oxidation reactions, has been scarcely investigated.

In this study, high-valent chromium-oxo porphyrin species, namely CrIV-oxo and CrV-oxo species, with electron-donating tetramesitylporphyrin(TMP) ligand were successfully generated and characterized with UV-vis, ESI-MS, …


An Afm Approach Applied In A Study Of Α-Crystallin Membrane Association: New Insights Into Lens Hardening And Presbyopia Development, Nawal K. Khadka, Raju Timsina, Laxman Mainali May 2022

An Afm Approach Applied In A Study Of Α-Crystallin Membrane Association: New Insights Into Lens Hardening And Presbyopia Development, Nawal K. Khadka, Raju Timsina, Laxman Mainali

Physics Faculty Publications and Presentations

The lens of the eye loses elasticity with age, while α-crystallin association with the lens membrane increases with age. It is unclear whether there is any correlation between α-crystallin association with the lens membrane and loss in lens elasticity. This research investigated α-crystallin membrane association using atomic force microscopy (AFM) for the first time to study topographical images and mechanical properties (breakthrough force and membrane area compressibility modulus (KA), as measures of elasticity) of the membrane. α-Crystallin extracted from the bovine lens cortex was incubated with a supported lipid membrane (SLM) prepared on a flat mica surface. The …


Acoustic Waves In The Upper Atmosphere, Geoffrey Blayne Schulthess May 2022

Acoustic Waves In The Upper Atmosphere, Geoffrey Blayne Schulthess

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Atmospheric waves can be generated by tropospheric sources such as earthquakes and explosions, causing significant disturbances in the upper atmosphere and ionosphere, where radio wave communications take place. For this analysis, they will be separated into two sub-groups called acoustic waves and gravity waves. Because each of these waves have unique frequency ranges, they can be observed and measured in order to determine their source type and location. Past studies attempted to build the connections between these waves with severe storms and earthquakes, which have improved our understanding of their complexity. Because of the complex nature of these waves, simplified …


Electrothermal Plenum Thruster Simulations Varying Input Pressure And Voltage, Naomi Nicole Ingram May 2022

Electrothermal Plenum Thruster Simulations Varying Input Pressure And Voltage, Naomi Nicole Ingram

Open Access Theses & Dissertations

A radiofrequency electrothermal thruster is designed and simulated to create a low ionization energy plasma from a neutral propellant using a radio-frequency power. With an asymmetrical surface area ratio between the grounded and powered electrode, ion-neutral charge exchange collisions occurring within the propellant result in propellant heating. The Electrothermal Plenum Thruster conducts this propellant heating in an annular plenum chamber in attempt to maximize propellant heating. A software called CFD-ACE+ is utilized to demonstrate the effects of an enhanced sheath from the asymmetrical power coupling arrangement. Two sets of simulations are run to understand how input variables affect the plasma …