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- Doxorubicin (3)
- Drug delivery (3)
- Ultrasound (3)
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- Chemotherapy (2)
- AP/HTPB flame structure (1)
- Acoustic spectroscopy (1)
- Alcohol dimers (1)
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- CO (1)
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Articles 1 - 21 of 21
Full-Text Articles in Chemical Engineering
Transient Molecular Dynamics Simulations Of Viscosity For Simple Fluids, Richard L. Rowley, Jason C. Thomas
Transient Molecular Dynamics Simulations Of Viscosity For Simple Fluids, Richard L. Rowley, Jason C. Thomas
Faculty Publications
A transient molecular dynamics (TMD) method has been developed for simulation of fluid viscosity. In this method a sinusoidal velocity profile is instantaneously overlaid onto equilibrated molecular velocities, and the subsequent decay of that velocity profile is observed. The viscosity is obtained by matching in a least-squares sense the analytical solution of the corresponding momentum transport boundary-value problem to the simulated decay of the initial velocity profile. The method was benchmarked by comparing results obtained from the TMD method for a Lennard-Jones fluid with those previously obtained using equilibrium molecular dynamics (EMD) simulations. Two different constitutive models were used in …
Two-Dimensional Modeling Of Ap/Htpb Utilizing A Vorticity Formulation And One-Dimensional Modeling Of Ap And Adn, Matthew L. Gross
Two-Dimensional Modeling Of Ap/Htpb Utilizing A Vorticity Formulation And One-Dimensional Modeling Of Ap And Adn, Matthew L. Gross
Theses and Dissertations
This document details original numerical studies performed by the author pertaining to the propellant oxidizer, ammonium perchlorate (AP). Detailed kinetic mechanisms have been utilized to model the combustion of the monopropellants AP and ADN, and a two-dimensional diffusion flame model has been developed to examine the flame structure above an AP/HTPB composite propellant. This work was part of an ongoing effort to develop theoretically based, a priori combustion models. The improved numerical model for AP combustion utilizes a “universal” gas-phase kinetic mechanism previously applied to combustion models of HMX, RDX, GAP, GAP/RDX, GAP/HMX, NG, BTTN, TMETN, GAP/BTTN, and GAP/RDX/BTTN. The …
Potential Energy Surfaces For Small Alcohol Dimers. Ii. Propanol, Isopropanol, T-Butanol, And Sec-Butanol, Richard L. Rowley, Christopher M. Tracy, Tapani A. Pakkanen
Potential Energy Surfaces For Small Alcohol Dimers. Ii. Propanol, Isopropanol, T-Butanol, And Sec-Butanol, Richard L. Rowley, Christopher M. Tracy, Tapani A. Pakkanen
Faculty Publications
Potential energy landscapes for homogeneous dimers of propanol, isopropanol, tert-butanol, and sec-butanol were obtained using 735 counterpoise-corrected energies at the MP2/6-311+G(2df,2pd) level. The landscapes were sampled at 15 dimer separation distances for different relative monomer geometries, or routes, given in terms of the yaw, pitch, and roll of one monomer relative to the other and the spherical angles between the two monomer centers (taken as the C atom attached to the O). The resultant individual energy surfaces and their complex topographies were also regressed using a site-site pair potential model using a modified Morse potential that provides a mathematically simple …
Bubble Dynamics Of Ultrasonic Drug Release From Polymeric Micelles, Mario A. Diaz, William G. Pitt
Bubble Dynamics Of Ultrasonic Drug Release From Polymeric Micelles, Mario A. Diaz, William G. Pitt
Faculty Publications
We have reported the ability of Pluronic P-105 micelles to sequester anthracycline drugs and release their contents upon application of 70 kHz ultrasound (US)1 (Figure 1). Optimal targeting to tumors depends on focus and control of US insonation, which is better achieved at higher frequencies. While no evidence of in vitro drug release was found at 500 kHz, drug release at 70 kHz correlates with the intensity of the subharmonic signal in the acoustic spectrum generated by the insonated bubbles2(Figure 2). Having established that bubble oscillations (cavitation) are directly related to drug release at 70 kHz, we now investigate the …
Ultrasonically-Assisted Drug Delivery In Rats Reduces Tumor Growth, William G. Pitt, Beverly L. Roeder, G. Bruce Schaalje, Bryant J. Staples
Ultrasonically-Assisted Drug Delivery In Rats Reduces Tumor Growth, William G. Pitt, Beverly L. Roeder, G. Bruce Schaalje, Bryant J. Staples
Faculty Publications
Previously we have shown that nanosized drug carriers called Plurogels™ sequestered Doxorubicin (Dox) and partially released this drug with application of ultrasound (US) (Fig. 1)1. The application to chemotherapy was successfully demonstrated in a rat tumor model2. However previous studies did not examine the distribution of Dox in the insonated and control tissue. This recent work investigated the effect of two US frequencies and examined the Dox distribution in the insonated and control tumors to determine if US was depositing more Dox at the insonated site.
A New Method For Treating Wells In Reservoir Simulation, Gregory M. Gessel
A New Method For Treating Wells In Reservoir Simulation, Gregory M. Gessel
Theses and Dissertations
A new method for formulating finite difference equations for reservoir simulation has been developed. It can be applied throughout the entire simulated reservoir or to local segments. When applied to cells containing vertical, fully penetrating, straight-line wells in a homogeneous reservoir, the resulting equations are equivalent to Peaceman's classical well equations used in most reservoir simulators today. However, when the new finite difference equations are applied to both the well-containing cells, and their neighbors, the accuracy of the simulation improves substantially. The method produces still better accuracy results when applied throughout the reservoir. Unlike the Peaceman correction, the new method …
Pharmacokinetics Of Ultrasonically-Released, Micelle-Encapsulated Doxorubicin In The Rat Model And Its Effect On Tumor Growth, Bryant J. Staples
Pharmacokinetics Of Ultrasonically-Released, Micelle-Encapsulated Doxorubicin In The Rat Model And Its Effect On Tumor Growth, Bryant J. Staples
Theses and Dissertations
Chemotherapy is one of the most successful cancer treatments used today. Unfortunately, the amount of chemotherapy a patient can receive is limited by the associated negative side effects, such as cardiotoxicity, immune system suppression, and nephrotoxicity. Encapsulation of these drugs, Doxorubicin (DOX) in particular, in stabilized Pluronic micelles (Plurogel TM) shows success in limiting these harmful side effects. In previous studies, low-frequency ultrasound (US) has been shown, in vitro, to locally release DOX from these micelles. In this study, a novel drug delivery system involving the encapsulation of DOX in Plurogel and the release of the drug at the tumor …
Biomass And Coal Fly Ash In Concrete: Strength, Durability, Microstructure, Quantitative Kinetics Of Pozzolanic Reaction And Alkali Silica Reaction Investigations., Shuangzhen Wang
Theses and Dissertations
Biomass represents an important sustainable energy resource, with biomass-coal cofiring representing among the most effective and cost efficient CO2 reduction strategies. Fly ash generated during coal combustion represents a technically advantageous, inexpensive, and environmentally beneficial admixture in concrete production, partially replacing cement. However, strict interpretation of American Society of Testing and Materials (ASTM) and American Concrete Institute (ACI) standards prohibits use of fly ashes from any source other than coal in concrete production; therefore, fly ash from biomass coal cofiring is excluded from use in concrete. This dissertation discusses biomass impacts on concrete properties through experiments conducted on several combinations …
Modeling Three Reacting Flow Systems With Modern Computational Fluid Dynamics, Ralph J. Price
Modeling Three Reacting Flow Systems With Modern Computational Fluid Dynamics, Ralph J. Price
Theses and Dissertations
Computational fluid dynamics (CFD) modeling and analysis were used in three projects: solar CO2 conversion modeling, improved coal combustion modeling using STAR-CD, and premixed combustion modeling. Each project is described below. The solar CO2 conversion modeling project involved CFD simulations of a prototype solar CO2 converter that uses sunlight to dissociate CO2 into CO and O2. Modeling was used to predict the performance of this prototype converter using three CFD software packages, and involved predicting the flow, heat transfer, and chemical kinetics. Accuracy was determined by comparison of model predictions and experimental data. Parametric modeling studies were performed in order …
Production Of Hydrogen And Sulfur From Hydrogen Sulfide In A Nonthermal-Plasma Pulsed Corona Discharge Reactor, Morris D. Argyle, Gui-Bing Zhao, Sanil John, Ji-Jun Zhang, Jerry C. Hamann, Suresh S. Muknahallipatna, Stanislaw Legowski, John F. Ackerman
Production Of Hydrogen And Sulfur From Hydrogen Sulfide In A Nonthermal-Plasma Pulsed Corona Discharge Reactor, Morris D. Argyle, Gui-Bing Zhao, Sanil John, Ji-Jun Zhang, Jerry C. Hamann, Suresh S. Muknahallipatna, Stanislaw Legowski, John F. Ackerman
Faculty Publications
Hydrogen Sulfide (H2S) dissociation into hydrogen and sulfur has been studied in a pulsed corona discharge reactor (PCDR). Due to the high dielectric strength of pure H2S (~2.9 times higher than air), a non-thermal plasma could not be sustained in pure H2S at discharge voltages up to 30kV with our reactor geometry. Therefore, H2S was diluted with another gas with lower dielectric strength to reduce the breakdown voltage. Breakdown voltages of H2S in four balance gases (Ar, He, N2 and H2) have been measured at different H2S concentrations and pressures. Breakdown voltages are proportional to the partial pressure of H2S …
Continuous Co-Separation By Liquid Absorption In Aqueous Cuprous Chloride (Cucl) And Magnesium Chloride (Mgcl2) Solution, Paul J. Foster
Continuous Co-Separation By Liquid Absorption In Aqueous Cuprous Chloride (Cucl) And Magnesium Chloride (Mgcl2) Solution, Paul J. Foster
Theses and Dissertations
The purpose of the research was to design, build, test, and recommend a process to economically separate CO from a gas mixture of CO, CO2, and O2. The general method considered in this research to accomplish the separation was liquid absorption in a packed column. Several experiments were performed to identify the best process solution to use in a prototype. The experiments, based on the COSORB process, consisted of CuCl mixed with a complexing agent (metal tri-chloride) and a solvent (metal tetra-chloride, toluene, ethanol, etc.). The best method consisted of an aqueous solution of CuCl and MgCl2, which has previously …
Structure And Nitrogen Chemistry In Coal, Biomass, And Cofiring Low-Nox Flames, Bradley David Damstedt
Structure And Nitrogen Chemistry In Coal, Biomass, And Cofiring Low-Nox Flames, Bradley David Damstedt
Theses and Dissertations
Addressing global climate change will require increasing sustainable energy usage. Cofiring biomass fuels with coal for electrical power generation is an efficient, cost effective method of CO2 mitigation. This work is an experimental investigation of the flame structure and nitrogen chemistry differences occurring between coal, biomass and cofiring flames. A pilot-scale facility was fired with a dual-feed low-NOx burner capable of independently conveying 2 separate fuels unblended to the burner. Spatially detailed gas species measurements were made for 8 flames, including a coal, straw, finely ground straw, wood, and 4 straw/coal cofiring flames. Particle samples were also obtained from 5 …
The Role Of Ultrasound Cavitation In Liposome Size Reduction, William G. Pitt, Eric S. Richardson, Dixon J. Woodbury
The Role Of Ultrasound Cavitation In Liposome Size Reduction, William G. Pitt, Eric S. Richardson, Dixon J. Woodbury
Faculty Publications
Liposome size is a vital parameter of many quantitative biophysical studies. Sonication, or exposure to ultrasound, is used widely to manufacture artificial liposomes, yet little is known about the mechanism by which liposomes are affected by ultrasound. Cavitation, or the oscillation of small gas bubbles in a pressure-varying field, has been shown to be responsible for many biophysical effects of ultrasound on cells. Collapse cavitation is manifested in the acoustic spectrum by an f/2 subharmonic and an increase in broadband noise. In this study, we attempted to correlate the presence of cavitation with a decrease in liposome size. Lipid suspensions …
A Coarse Grain Model For Dna, Thomas A. Knotts, Nitin Rathore, David C. Schwartz, Juan J. De Pablo
A Coarse Grain Model For Dna, Thomas A. Knotts, Nitin Rathore, David C. Schwartz, Juan J. De Pablo
Faculty Publications
Understanding the behavior of DNA at the molecular level is of considerable fundamental and engineering importance. While adequate representations of DNA exist at the atomic and continuum level, there is a relative lack of models capable of describing the behavior of DNA at mesoscopic length scales. We present a mesoscale model of DNA that reduces the complexity of a nucleotide to three interactions sites, one each for the phosphate, sugar, and base, thereby rendering the investigation of DNA up to a few microns in length computationally tractable. The charges on these sites are considered explicitly. The model is parametrized using …
An Improved Model For Calculating Heats Of Dilution And Equilibrium Constants For High Temperature Aqueous Electrolyte Solutions, Xiaoyun Lin
Theses and Dissertations
At high temperatures, the properties of aqueous electrolyte systems differ markedly from those at 25°C. For mixed-electrolyte dilute solutions at high temperatures, the degree of ion-association is sufficiently large that the association equilibrium must be incorporated in any model describing the solutions. These association reactions usually do not occur to a measurable extent at room temperature. Oscarson and co-workers have designed a correlation model based on the excess Gibbs energy which can correlate log K and ∆H values as well as the heats of dilution for aqueous electrolyte systems as a function of temperature (T) and ionic strength (I) from …
High-Frequency Ultrasound Drug Delivery And Cavitation, Mario Alfonso Diaz
High-Frequency Ultrasound Drug Delivery And Cavitation, Mario Alfonso Diaz
Theses and Dissertations
The viability of a drug delivery system which encapsulates chemotherapeutic drugs (Doxorubicin) in the hydrophobic core of polymeric micelles and triggers release by ultrasound application was investigated at an applied frequency of 500 kHz. The investigation also included elucidating the mechanism of drug release at 70 kHz, a frequency which had previously been shown to induce drug release. A fluorescence detection chamber was used to measure in vitro drug release from both Pluronic and stabilized micelles and a hydrophone was used to monitor bubble activity during the experiments. A threshold for release between 0.35 and 0.40 in mechanical index was …
Using Computational Fluid Dynamics Modeling To Improve The Performance Of A Solar Co2 Converter, Thomas H. Fletcher, Ralph J. Price, Reed J. Jensen
Using Computational Fluid Dynamics Modeling To Improve The Performance Of A Solar Co2 Converter, Thomas H. Fletcher, Ralph J. Price, Reed J. Jensen
Faculty Publications
A solar collector to convert CO2 to CO at high temperature was previously developed, achieving a product with 4-6 mol % CO from pure CO2. Modeling results showed that reactions occurred in the thermal boundary layer of the heated zirconia rod at temperatures greater than 2300 K. This paper describes results of computer modeling of advanced designs meant to increase the conversion of CO from CO2. Several design modifications were tested using the model, including changing the cool-down region configuration, increasing the zirconia rod diameter, and changing the zirconia rod shape. Several operational adjustments were also modeled, including reducing the …
Model Compound Study Of The Pathways For Aromatic Hydrocarbon Formation In Soot, Randall E. Winans, Nancy A. Tomczyk, Jerry E. Hunt, Mark S. Solum, Ronald J. Pugmire, Thomas H. Fletcher
Model Compound Study Of The Pathways For Aromatic Hydrocarbon Formation In Soot, Randall E. Winans, Nancy A. Tomczyk, Jerry E. Hunt, Mark S. Solum, Ronald J. Pugmire, Thomas H. Fletcher
Faculty Publications
As a follow-up of previous work on the flame pyrolysis of biphenyl and pyrene, a more detailed analysis of the pyrolytic products has been done using additional NMR data obtained on the whole soot sample correlated with detailed high-resolution and GC mass spectrometry data on the solvent-extracted portion of the same samples. These latter data complement the earlier NMR data with details of the pre-sooting structures, referred to as “young soot”, in pyrolyzed biphenyl samples collected at 1365, 1410, and 1470 K and pyrene at 1410 and 1470 K. The data reveal the roles played by free-radical-assisted polymerization reactions as …
Heat And Mass Transport In Heat Pipe Wick Structures, Brian D. Iverson, Tyler W. Davis, Suresh V. Garimella, Mark T. North, Sukhvinder S. Kang
Heat And Mass Transport In Heat Pipe Wick Structures, Brian D. Iverson, Tyler W. Davis, Suresh V. Garimella, Mark T. North, Sukhvinder S. Kang
Faculty Publications
A novel experimental approach is developed for characterizing the performance of heat pipe wick structures. This approach simulates the actual operation of wick structures in a heat pipe. Open, partially submerged, sintered copper wicks of varying pore size are studied under the partially saturated conditions found in normal heat pipe operation. A vertical wick orientation, where the capillary lift is in opposition to gravity, is selected to test the wicks under the most demanding conditions. Mass transport measurements of the working fluid, in addition to the temperature field, are obtained for the porous wicks under the action of a discrete …
Effects Of Moisture On Ignition Behavior Of Moist California Chaparral And Utah Leaves, Thomas H. Fletcher, Brent M. Pickett, Steven G. Smith, Gregory S. Spittle, Megan M. Woodhouse, Elizabeth Haake, David R. Weise
Effects Of Moisture On Ignition Behavior Of Moist California Chaparral And Utah Leaves, Thomas H. Fletcher, Brent M. Pickett, Steven G. Smith, Gregory S. Spittle, Megan M. Woodhouse, Elizabeth Haake, David R. Weise
Faculty Publications
Individual cuttings from eight plant species native to California chaparral or Utah were burned in a well-controlled, well-instrumented facility. Gas temperatures above a flat-flame burner were controlled at 987 C and 10 mol% O2, resulting in a heat flux at the leaf surface varying from 80–140 kW/m2. High moisture leaves were observed to burst due to the rapid escape of vapor from the leaf interior. Bubbles in or on the leaf surface were observed for leaves with moderate moisture contents. A large number of leaf temperature measurements were made, along with measurements of the ignition time …
High-Pressure Turbine Deposition In Land-Based Gas Turbines From Various Synfuels, Thomas H. Fletcher
High-Pressure Turbine Deposition In Land-Based Gas Turbines From Various Synfuels, Thomas H. Fletcher
Faculty Publications
Ash deposits from four candidate power turbine synfuels were studied in an accelerated deposition test facility. The facility matches the gas temperature and velocity of modern first-stage high-pressure turbine vanes. A natural gas combustor was seeded with finely ground fuel ash particulate from four different fuels: straw, sawdust, coal, and petroleum coke. The entrained ash particles were accelerated to a combustor exit flow Mach number of 0.31 before impinging on a thermal barrier coating (TBC) target coupon at 1150°C. Postexposure analyses included surface topography, scanning electron microscopy, and x-ray spectroscopy. Due to significant differences in the chemical composition of the …