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Faculty Publications

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Articles 241 - 270 of 914

Full-Text Articles in Chemical Engineering

Hypermongone C Accelerates Wound Healing Through The Modulation Of Inflammatory Factors And Promotion Of Fibroblast Migration, Sara E. Moghadam, Moridi Mahdi Farimani, Sara Soroury, Samad N. Ebrahimi, Ehsan Jabbarzadeh May 2019

Hypermongone C Accelerates Wound Healing Through The Modulation Of Inflammatory Factors And Promotion Of Fibroblast Migration, Sara E. Moghadam, Moridi Mahdi Farimani, Sara Soroury, Samad N. Ebrahimi, Ehsan Jabbarzadeh

Faculty Publications

The physiology of wound healing is dependent on the crosstalk between inflammatory mediators and cellular components of skin regeneration including fibroblasts and endothelial cells. Therefore, strategies to promote healing must regulate this crosstalk to achieve maximum efficacy. In light of the remarkable potential of natural compounds to target multiple signaling mechanisms, this study aims to demonstrate the potential of hypermongone C, a polycyclic polyprenylated acylphloroglucinol (PPAP), to accelerate wound closure by concurrently enhancing fibroblast proliferation and migration, promoting angiogenesis, and suppressing pro-inflammatory cytokines. This compound belongs to a family of plants (Hypericum) that traditionally have been used to treat injuries. …


Non-Canonical Amino Acid Labeling In Proteomics And Biotechnology, Aya M. Saleh, Kristen M. Wilding, Sarah Calve, Bradley Charles Bundy, Tamara L. Kinzer-Ursem May 2019

Non-Canonical Amino Acid Labeling In Proteomics And Biotechnology, Aya M. Saleh, Kristen M. Wilding, Sarah Calve, Bradley Charles Bundy, Tamara L. Kinzer-Ursem

Faculty Publications

Metabolic labeling of proteins with non-canonical amino acids (ncAAs) provides unique bioorthogonal chemical groups during de novo synthesis by taking advantage of both endogenous and heterologous protein synthesis machineries. Labeled proteins can then be selectively conjugated to fluorophores, affinity reagents, peptides, polymers, nanoparticles or surfaces for a wide variety of downstream applications in proteomics and biotechnology. In this review, we focus on techniques in which proteins are residue- and site-specifically labeled with ncAAs containing bioorthogonal handles. These ncAA-labeled proteins are: readily enriched from cells and tissues for identification via mass spectrometry-based proteomic analysis; selectively purified for downstream biotechnology applications; or …


Mass-Transfer Driven Spinodal Decomposition In A Ternary Polymer Solution, Douglas R. Tree, Lucas F. Dos Santos, Caden B. Wilson, Timothy R. Scott, Jan Ulric Garcia, Glenn H. Fredrickson Apr 2019

Mass-Transfer Driven Spinodal Decomposition In A Ternary Polymer Solution, Douglas R. Tree, Lucas F. Dos Santos, Caden B. Wilson, Timothy R. Scott, Jan Ulric Garcia, Glenn H. Fredrickson

Faculty Publications

Nonsolvent induced phase separation (NIPS) is a widely occuring process used in industrial membrane production, nanotechnology and Nature to produce microstructured polymer materials. A variety of process-dependent morphologies are produced when a polymer solution is exposed to a nonsolvent that, following a period where mass is exchanged, precipitates and solidifies the polymer. Despite years of investigation, both experimental and theoretical, many questions surround the pathways to the microstructures that NIPS can produce. Here, we provide simulation results from a model that simultaneously captures both the processess of solvent/nonsolvent exchange and phase separation. We show that the time it takes the …


Reactions At Noble Metal Contacts With Methylammonium Lead Triiodide Perovskites: Role Of Underpotential Deposition And Electrochemistry, Ross A. Kerner, Philip Schulz, Jeffrey A. Christians, Sean P. Dunfield, Benjia Dou, Lianfeng Zhao, Glenn Teeter, Joseph J. Berry, Barry P. Rand Apr 2019

Reactions At Noble Metal Contacts With Methylammonium Lead Triiodide Perovskites: Role Of Underpotential Deposition And Electrochemistry, Ross A. Kerner, Philip Schulz, Jeffrey A. Christians, Sean P. Dunfield, Benjia Dou, Lianfeng Zhao, Glenn Teeter, Joseph J. Berry, Barry P. Rand

Faculty Publications

Chemical reactivity of halide perovskites coupled with a low energy of formation makes it a challenge to characterize material properties and achieve long-term device stability. In this study, we elucidate electrochemical reactions occurring at the methylammonium lead triiodide (MAPbI3)/Au interface. X-ray photoemission spectroscopy is used to identify a type of reduction/oxidation reaction termed underpotential deposition (UPD) involving lead, iodine, and hydrogen occurring at interfaces with noble metals. Changes in surface compositions and oxidation states suggest that UPD derived adsorbates at MAPbI3/Au interfaces lower the energy barrier for release of volatile HI and/or I2catalyzing degradation …


Intelligent Machine Learning: Tailor-Making Macromolecules, Yousef Mohammadi, Mohammad Reza Saeb, Alexander Penlidis, Esmaiel Jabbari, Florian J. Stadler, Philippe Zinck, Krzysztof Matyjaszewski Apr 2019

Intelligent Machine Learning: Tailor-Making Macromolecules, Yousef Mohammadi, Mohammad Reza Saeb, Alexander Penlidis, Esmaiel Jabbari, Florian J. Stadler, Philippe Zinck, Krzysztof Matyjaszewski

Faculty Publications

Nowadays, polymer reaction engineers seek robust and effective tools to synthesize complex macromolecules with well-defined and desirable microstructural and architectural characteristics. Over the past few decades, several promising approaches, such as controlled living (co)polymerization systems and chain-shuttling reactions have been proposed and widely applied to synthesize rather complex macromolecules with controlled monomer sequences. Despite the unique potential of the newly developed techniques, tailor-making the microstructure of macromolecules by suggesting the most appropriate polymerization recipe still remains a very challenging task. In the current work, two versatile and powerful tools capable of effectively addressing the aforementioned questions have been proposed and …


Material And Regenerative Properties Of An Osteon-Mimetic Cortical Bone-Like Scaffold, Danial Barati, Ozan Karaman, Seyedsina Moeinzadeh, Safaa Kader, Esmaiel Jabbari Mar 2019

Material And Regenerative Properties Of An Osteon-Mimetic Cortical Bone-Like Scaffold, Danial Barati, Ozan Karaman, Seyedsina Moeinzadeh, Safaa Kader, Esmaiel Jabbari

Faculty Publications

The objective of this work was to fabricate a rigid, resorbable and osteoconductive scaffold by mimicking the hierarchical structure of the cortical bone. Aligned peptide-functionalize nanofiber microsheets were generated with calcium phosphate (CaP) content similar to that of the natural cortical bone. Next, the CaP-rich fibrous microsheets were wrapped around a microneedle to form a laminated microtube mimicking the structure of an osteon. Then, a set of the osteon-mimetic microtubes were assembled around a solid rod and the assembly was annealed to fuse the microtubes and form a shell. Next, an array of circular microholes were drilled on the outer …


Model Predictive Automatic Control Of Sucker Rod Pump System With Simulation Case Study, Brigham Hansen, Brandon Tolbert, Cory Vernon, John Hedengren Feb 2019

Model Predictive Automatic Control Of Sucker Rod Pump System With Simulation Case Study, Brigham Hansen, Brandon Tolbert, Cory Vernon, John Hedengren

Faculty Publications

This work enables accelerated fluid recovery in oil and gas reservoirs by automatically controlling fluid height and bottomhole pressure in wells. Several literature studies show significant increase in recovered oil by determining a target bottomhole pressure but rarely consider how to control to that value. This work enables those benefits by maintaining bottomhole pressure or fluid height. Moving Horizon Estimation (MHE) determines uncertain well parameters using only common surface measurements. A Model Predictive Controller (MPC) adjusts the stroking speed of a sucker rod pump to maintain fluid height. Pump boundary conditions are simulated with Mathematical Programs with Complementarity Constraints (MPCCs) …


Heating Rate And Temperature Effects On Pyrolysis Products From Live Wildland Fuels, Mohammad-Saeed Safdari, Elham Amini, David R. Weise, Thomas H. Fletcher Jan 2019

Heating Rate And Temperature Effects On Pyrolysis Products From Live Wildland Fuels, Mohammad-Saeed Safdari, Elham Amini, David R. Weise, Thomas H. Fletcher

Faculty Publications

Wildland fire, which includes both planned (prescribed fire) and unplanned (wildfire) fires, is an important component of many ecosystems. During wildland fires, low heating rate pyrolysis (slow pyrolysis) occurs during preheating and/or smoldering of plant material. High heating rate pyrolysis (fast pyrolysis) exists in the flame region. Pyrolysis temperature and heating rate play important roles on the yields and the compositions of pyrolysis products. In this work, the effects of pyrolysis temperature and heating rate on the yields and the compositions of pyrolysis products from 14 plant species native to the forests of the southern United States are shown. The …


Correlations Of The Elemental Compositions Of Primary Coal Tar And Char, Andrew P. Richards, Colson Johnson, Thomas H. Fletcher Jan 2019

Correlations Of The Elemental Compositions Of Primary Coal Tar And Char, Andrew P. Richards, Colson Johnson, Thomas H. Fletcher

Faculty Publications

Simulations of large-scale coal combustors rely on accurate submodels to describe the chemical and physical changes in coal during reaction. Typically, simplified empirical submodels are tuned to experimental data to reduce the computational complexity. When data are not readily available, simplifying assumptions are used, which can create inaccuracies and biases in a large simulation. One such simplifying assumption in coal research is how to describe the elemental composition of primary pyrolysis products. This paper explores several different empirical model forms to predict the dry, ash-free fractions of C, H, O, N, and S in both the char and tar, using …


Modified Cpd Model For Coal Devolatilization At Underground Coal Thermal Treatment Conditions, Ding Wang, Thomas H. Fletcher, Swomitra Mohanty, Hoaquan Hu, Eric G. Eddings Jan 2019

Modified Cpd Model For Coal Devolatilization At Underground Coal Thermal Treatment Conditions, Ding Wang, Thomas H. Fletcher, Swomitra Mohanty, Hoaquan Hu, Eric G. Eddings

Faculty Publications

To study coal pyrolysis behavior at underground coal thermal treatment (UCTT) conditions, a modified CPD (M-CPD) model was developed and evaluated using two scales of experiments as well as two different coals, Utah Sufco and Illinois #6. Compared with the original CPD model, three major aspects were changed, including (1) rewriting the algorithm using MATLAB built-in functions; (2) developing a correlation method between coal elemental composition and the initial functional group population to calculate the effect of cross-linking on the lattice structure; and (3) using a two-activation energy approach for gas generation kinetics modeling. Results predicted by the M-CPD model …


Characterization Of Pyrolysis Products From Slow Pyrolysis Of Live And Dead Vegetation Native To The Southern United States, Elham Amini, Mohammad-Saeed Safdari, Jonathan Deyoung, David R. Weise, Thomas H. Fletcher Jan 2019

Characterization Of Pyrolysis Products From Slow Pyrolysis Of Live And Dead Vegetation Native To The Southern United States, Elham Amini, Mohammad-Saeed Safdari, Jonathan Deyoung, David R. Weise, Thomas H. Fletcher

Faculty Publications

Prescribed (i.e., controlled) burning is a common practice used in many vegetation types in the world to accomplish a wide range of land management objectives including wildfire risk reduction, wildlife habitat improvement, forest regeneration, and land clearing. To properly apply controlled fire and reduce unwanted fire behavior, an improved understanding of fundamental processes related to combustion of live and dead vegetation is needed. Since the combustion process starts with pyrolysis, there is a need for more data and better models of pyrolysis of live and dead fuels. In this study, slow pyrolysis experiments were carried out in a pyrolyzer apparatus …


Effects Of Seawater On Carotenoid Production And Lipid Content Of Engineered Saccharomyces Cerevisiae, Yuqi Guo, Shangxian Xie, Joshua Yuan, Katy Kao Jan 2019

Effects Of Seawater On Carotenoid Production And Lipid Content Of Engineered Saccharomyces Cerevisiae, Yuqi Guo, Shangxian Xie, Joshua Yuan, Katy Kao

Faculty Publications

The use of seawater in fermentation can potentially reduce the freshwater burden in the bio-based production of chemicals and fuels. We previously developed a Saccharomyces cerevisiae carotenoids hyperproducer SM14 capable of accumulating 18 mg g−1 DCW (DCW: dry cell weight) of β-carotene in rich media (YPD). In this work, the impacts of seawater on the carotenoid production of SM14 were investigated. When using nutrient-reduced media (0.1× YNB) in freshwater the β-carotene production of SM14 was 6.51 ± 0.37 mg g−1 DCW; however in synthetic seawater, the production was increased to 8.67 ± 0.62 mg g−1 DCW. We found that this …


Review Of Carbonaceous Annealing Effects On O2 And Co2 Coal Reactivity, Troy Michael Holland, Thomas H. Fletcher, Osvalda Senneca Jan 2019

Review Of Carbonaceous Annealing Effects On O2 And Co2 Coal Reactivity, Troy Michael Holland, Thomas H. Fletcher, Osvalda Senneca

Faculty Publications

Coal is, and will remain for the foreseeable future, a critical energy production resource. Advanced models of coal conversion behavior in air and oxy-coal environments enhance the boiler operational efficiency and design optimization. Although coal conversion models have continuously improved over decades of research, not all aspects of coal particle heating and conversion have received equal treatment. Coal particle annealing is one aspect of the coal conversion process that is simultaneously highly sensitive to the conversion environment, exceptionally impactful on coal chemistry, and frequently neglected in coal models. However, the current body of literature has explored numerous aspects of coal …


Pyrolysis Kinetics Of Live And Dead Wildland Vegetation From The Southern United States, Elham Amini, Mohammad-Saeed Safdari, David R. Weise, Thomas H. Fletcher Jan 2019

Pyrolysis Kinetics Of Live And Dead Wildland Vegetation From The Southern United States, Elham Amini, Mohammad-Saeed Safdari, David R. Weise, Thomas H. Fletcher

Faculty Publications

The fundamental combustion behavior of live wildland vegetation is not fully understood. Since the combustion process during wildland fire starts with pyrolysis, there is a need for better understanding of pyrolysis to develop improved wildland fire models. The kinetics of pyrolysis of live and dead wildland vegetation has not been explored in detail. In this study, the pyrolysis kinetics were determined for 14 different plant species (live and dead) which are all native to the forests in the southern United States. Pyrolysis experiments were carried out in a Thermogravimetric analyzer (TGA) under inert conditions at 5 different heating rates ranged …


Dynamic Optimization Of High-Altitude Solar Aircraft Trajectories Under Station-Keeping Constraints, R. Abraham Martin, Nathaniel S. Gates, Andrew Ning, John Hedengren Nov 2018

Dynamic Optimization Of High-Altitude Solar Aircraft Trajectories Under Station-Keeping Constraints, R. Abraham Martin, Nathaniel S. Gates, Andrew Ning, John Hedengren

Faculty Publications

This paper demonstrates the use of nonlinear dynamic optimization to calculate energy-optimal trajectories for a high-altitude, solar-powered unmanned aerial vehicle (UAV). The objective is to maximize the total energy in the system while staying within a 3 km mission radius and meeting other system constraints. Solar energy capture is modeled using the vehicle orientation and solar position, and energy is stored both in batteries and in potential energy through elevation gain. Energy capture is maximized by optimally adjusting the angle of the aircraft surface relative to the sun. The UAV flight and energy system dynamics are optimized over a 24 …


Analysis Of Particle Behavior Inside The Classifier Of A Raymond Bowl Mill While Co-Milling Woody Biomass With Coal, Seyedhassan Fakourian, Andrew R. Fry, Tanner Jasperson Oct 2018

Analysis Of Particle Behavior Inside The Classifier Of A Raymond Bowl Mill While Co-Milling Woody Biomass With Coal, Seyedhassan Fakourian, Andrew R. Fry, Tanner Jasperson

Faculty Publications

Woody biomass cofiring with coal at existing pulverized-coal boilers is known to be a green energy source and is a low-expense alternative for pure coal combustion. Co-milling woody biomass particles (15 wt%) with coal particles (85 wt%) before burning at a boiler is a complex problem because large woody biomass particles (>300 μm) exit the milling system along with the fine particles. A Computational Particle Fluid Dynamics (CPFD) is used in this paper to present a novel analysis about the behavior of woody biomass particles as they are mixed with coal particles inside the classifier. To meet this …


The Effects Of Antigen Size, Binding Site Valency, And Flexibility On Fab-Antigen Binding Near Solid Surfaces, Thomas A. Knotts, Derek B. Bush Oct 2018

The Effects Of Antigen Size, Binding Site Valency, And Flexibility On Fab-Antigen Binding Near Solid Surfaces, Thomas A. Knotts, Derek B. Bush

Faculty Publications

Next generation antibody microarray devices have the potential to outperform current molecular detection methods and realize new applications in medicine, scientific research, and national defense. However, antibody microarrays, or arrays of antibody fragments (“fabs”), continue to evade mainstream use in part due to persistent reliability problems despite improvements to substrate design and protein immobilization strategies. Other factors could be disrupting microarray performance, including effects resulting from antigen characteristics. Target molecules embody a wide range of sizes, shapes, number of epitopes, epitope accessibility, and other physical and chemical properties. As a result, it may not be ideal for microarray designs to …


In-Situ Electrochemical Analysis Of Microbial Activity, Ariane L. Martin, Pongsarun Satjaritanun, Sirivatch Shimpalee, Blake A. Devivo, John Weidner, Scott Greenway, J. Michael Henson, Charles E. Turick Oct 2018

In-Situ Electrochemical Analysis Of Microbial Activity, Ariane L. Martin, Pongsarun Satjaritanun, Sirivatch Shimpalee, Blake A. Devivo, John Weidner, Scott Greenway, J. Michael Henson, Charles E. Turick

Faculty Publications

Microbes have a wide range of metabolic capabilities available that makes them industrially useful organisms. Monitoring these metabolic processes is a crucial component in efcient industrial application. Unfortunately, monitoring these metabolic processes can often be invasive and time consuming and expensive, especially within an anaerobic environment. Electrochemical techniques, such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) ofer a non-invasive approach to monitor microbial activity and growth. EIS and CV were used to monitor Clostridium phytofermentans, an anaerobic and endospore-forming bacterium. C. phytofermentans ferments a wide range of sugars into hydrogen, acetate, and ethanol as fermentation by-products. For this …


Performance Comparison Of Low Temperature And Chemical Absorption Carbon Capture Processes In Response To Dynamic Electricity Demand And Price Profiles, Seyed Mostafa Safdarnejad, John Hedengren, Kody M. Powell Oct 2018

Performance Comparison Of Low Temperature And Chemical Absorption Carbon Capture Processes In Response To Dynamic Electricity Demand And Price Profiles, Seyed Mostafa Safdarnejad, John Hedengren, Kody M. Powell

Faculty Publications

Current projections to the year 2050 reveal that fossil fuels will remain the main source of energy generation. To achieve the target limits of carbon dioxide emission, set by national and international policies, carbon capture will play a key role. Modeling and optimization of various carbon capture technologies such as pre-combustion, oxy-fuel, and post-combustion, when integrated with coal-fired power plants, have been researched extensively in literature. Research on the integration of power generation with capture technologies regarding comparisons between the different schemes in response to dynamic inputs is lacking. This work provides a comparison between a low temperature carbon capture …


Statistically Guided Synthesis Of Mov- Based Mixed Oxide Catalysts For Ethane Partial Oxidation, Juan D. Jimenez, Kathleen Mingle, Teeraya Bureerug, Cun Wen, Jochen Lauterbach Sep 2018

Statistically Guided Synthesis Of Mov- Based Mixed Oxide Catalysts For Ethane Partial Oxidation, Juan D. Jimenez, Kathleen Mingle, Teeraya Bureerug, Cun Wen, Jochen Lauterbach

Faculty Publications

The catalytic performance of Mo8V2Nb1-based mixed-oxide catalysts for ethane partial oxidation is highly sensitive to the doping of elements with redox and acid functionality. Specifically, control over product distributions to ethylene and acetic acid can be afforded via the specific pairing of redox elements (Pd, Ni, Ti) and acid elements (K, Cs, Te) and the levels at which these elements are doped. The redox element, acid element, redox/acid ratio, and dopant/host ratio were investigated using a three-level, four-factor factorial screening design to establish relationships between catalyst composition, structure, and product distribution for ethane partial oxidation. Results show that the balance …


Statistically Guided Synthesis Of Mov-Based Mixed-Oxide Catalysts For Ethane Partial Oxidation, Juan D. Jimenez, Kathleen Mingle, Teeraya Bureerug, Cun Wen, Jochen A. Lauterbach Sep 2018

Statistically Guided Synthesis Of Mov-Based Mixed-Oxide Catalysts For Ethane Partial Oxidation, Juan D. Jimenez, Kathleen Mingle, Teeraya Bureerug, Cun Wen, Jochen A. Lauterbach

Faculty Publications

The catalytic performance of Mo8V2Nb1-based mixed-oxide catalysts for ethane partial oxidation is highly sensitive to the doping of elements with redox and acid functionality. Specifically, control over product distributions to ethylene and acetic acid can be afforded via the specific pairing of redox elements (Pd, Ni, Ti) and acid elements (K, Cs, Te) and the levels at which these elements are doped. The redox element, acid element, redox/acid ratio, and dopant/host ratio were investigated using a three-level, four-factor factorial screening design to establish relationships between catalyst composition, structure, and product distribution for ethane partial oxidation. Results show that the balance …


Rates Of Cavity Filling By Liquids, Dongjin Seo, Alex M. Schrader, Szu-Ying Chen, Yair Kaufman, Thomas R. Cristiani, Steven H. Page, Peter H. Koenig, Yonas Gizaw, Dong Woog Lee, Jacob N. Israelachvili Jul 2018

Rates Of Cavity Filling By Liquids, Dongjin Seo, Alex M. Schrader, Szu-Ying Chen, Yair Kaufman, Thomas R. Cristiani, Steven H. Page, Peter H. Koenig, Yonas Gizaw, Dong Woog Lee, Jacob N. Israelachvili

Faculty Publications

Understanding the fundamental wetting behavior of liquids on surfaces with pores or cavities provides insights into the wetting phenomena associated with rough or patterned surfaces, such as skin and fabrics, as well as the development of everyday products such as ointments and paints, and industrial applications such as enhanced oil recovery and pitting during chemical mechanical polishing. We have studied, both experimentally and theoretically, the dynamics of the transitions from the unfilled/partially filled (Cassie–Baxter) wetting state to the fully filled (Wenzel) wetting state on intrinsically hydrophilic surfaces (intrinsic water contact angle < 90°, where the Wenzel state is always the thermodynamically favorable state, while a temporary metastable Cassie–Baxter state can also exist) to determine the variables that control the rates of such transitions. We prepared silicon wafers with cylindrical cavities of different geometries and immersed them in bulk water. With bright-field and confocal fluorescence microscopy, we observed the details of, and the rates associated with, water penetration into the cavities from the bulk. We find that unconnected, reentrant cavities (i.e., cavities that open up below the surface) have the slowest cavity-filling rates, while connected or non-reentrant cavities undergo very rapid transitions. Using these unconnected, reentrant cavities, we identified the variables that affect cavity-filling rates: (i) the intrinsic contact angle, (ii) …


Modeling Soot Formation From Solid Complex Fuels, Alexander J. Josephson, Rod R. Linn, David O. Lignell Jul 2018

Modeling Soot Formation From Solid Complex Fuels, Alexander J. Josephson, Rod R. Linn, David O. Lignell

Faculty Publications

A detailed model is proposed for predicting soot formation from complex solid fuels. The proposed model resolves two particle size distributions, one for soot precursors and another for soot particles. The precursor size distribution is represented with a sectional approach while the soot particle-size distribution is represented with the method of moments and an interpolative closure method is used to resolve fractional methods. Based on established mechanisms, this model includes submodels for precursor coagulation, growth, and consumption, as well as soot nucleation, surface growth, agglomeration, and consumption. The model is validated with comparisons to experimental data for two …


Hydrogels For Cell Delivery, Esmaiel Jabbari Jul 2018

Hydrogels For Cell Delivery, Esmaiel Jabbari

Faculty Publications

No abstract provided.


Gekko Optimization Suite, Logan Beal, Daniel Hill, Ronald Abraham Martin, John Hedengren Jul 2018

Gekko Optimization Suite, Logan Beal, Daniel Hill, Ronald Abraham Martin, John Hedengren

Faculty Publications

This paper introduces GEKKO as an optimization suite for Python. GEKKO specializes in dynamic optimization problems for mixed-integer, nonlinear, and differential algebraic equations (DAE) problems. By blending the approaches of typical algebraic modeling languages (AML) and optimal control packages, GEKKO greatly facilitates the development and application of tools such as nonlinear model predicative control (NMPC), real-time optimization (RTO), moving horizon estimation (MHE), and dynamic simulation. GEKKO is an object-oriented Python library that offers model construction, analysis tools, and visualization of simulation and optimization. In a single package, GEKKO provides model reduction, an object-oriented library for data reconciliation/model predictive control, and …


Integrated Scheduling And Control In Discrete-Time With Dynamic Parameters And Constraints, Logan Beal, Damon Petersen, David R. Grimsman, Sean Warnick, John Hedengren Jul 2018

Integrated Scheduling And Control In Discrete-Time With Dynamic Parameters And Constraints, Logan Beal, Damon Petersen, David R. Grimsman, Sean Warnick, John Hedengren

Faculty Publications

Integrated scheduling and control (SC) seeks to unify the objectives of the various layers of optimization in manufacturing. This work investigates combining scheduling and control using a nonlinear discrete-time formulation, utilizing the full nonlinear process model throughout the entire horizon. This discrete-time form lends itself to optimization with time-dependent constraints and costs. An approach to combined SC is presented, along with sample pseudo-binary variable functions to ease the computational burden of this approach. An initialization strategy using feedback linearization, nonlinear model predictive control, and continuous-time scheduling optimization is presented. The formulation is applied with a generic continuous stirred tank reactor …


Arrhenius Rate Chemistry-Informed Inter-Phase Source Terms (Arciist), Matthew J. Schwaab, Robert B. Greendyke, Bryan J. Steward Jul 2018

Arrhenius Rate Chemistry-Informed Inter-Phase Source Terms (Arciist), Matthew J. Schwaab, Robert B. Greendyke, Bryan J. Steward

Faculty Publications

Currently, in macro-scale hydrocodes designed to simulate explosive material undergoing shock-induced ignition, the state of the art is to use one of numerous reaction burn rate models. These burn models are designed to estimate the bulk chemical reaction rate. Unfortunately, these burn rate models are largely based on empirical data and must be recalibrated for every new material being simulated. We propose that the use of Arrhenius Rate Chemistry-Informed Interphase Source Terms (ARCIIST) in place of empirically derived burn models will improve the accuracy for these computational codes. A reacting chemistry model of this form was developed for the cyclic …


One-Dimensional Turbulence Modeling For Cylindrical And Spherical Flows: Model Formulation And Application, David O. Lignell, Victoria B. Lansinger, Juan Medina, Marten Klein, Alan R. Kerstein, Heiko Schmidt, Marco Fistler, Michael Oevermann Jun 2018

One-Dimensional Turbulence Modeling For Cylindrical And Spherical Flows: Model Formulation And Application, David O. Lignell, Victoria B. Lansinger, Juan Medina, Marten Klein, Alan R. Kerstein, Heiko Schmidt, Marco Fistler, Michael Oevermann

Faculty Publications

The one-dimensional turbulence (ODT) model resolves a full range of time and length scales and is computationally efficient. ODT has been applied to a wide range of complex multi-scale flows, such as turbulent combustion. Previous ODT comparisons to experimental data have focused mainly on planar flows. Applications to cylindrical flows, such as round jets, have been based on rough analogies, e.g., by exploiting the fortuitous consistency of the similarity scalings of temporally developing planar jets and spatially developing round jets. To obtain a more systematic treatment, a new formulation of the ODT model in cylindrical and spherical coordinates is presented …


Synthesis-Structure-Activity Relationships In Co3o4 Catalyzed Co Oxidation, Kathleen Mingle, Jochen A. Lauterbach May 2018

Synthesis-Structure-Activity Relationships In Co3o4 Catalyzed Co Oxidation, Kathleen Mingle, Jochen A. Lauterbach

Faculty Publications

In this work, a statistical design and analysis platform was used to develop cobalt oxide based oxidation catalysts prepared via one pot metal salt reduction. An emphasis was placed upon understanding the effects of synthesis conditions, such as heating regimen and Co2+ concentration on the metal salt reduction mechanism, the resultant nanomaterial properties (i.e., size, crystal structure, and crystal faceting), and the catalytic activity in CO oxidation. This was accomplished by carrying out XRD, TEM, and FTIR studies on synthesis intermediates and products. Additionally, high-throughput experimentation was employed to study the performance of Co3O4 oxidation catalysts over a wide range …


Baseline Effects Of Lysophosphatidylcholine And Nerve Growth Factor In A Rat Model Of Sciatic Nerve Regeneration After Crush Injury, Ryan L. Wood, Keaton S. Karlinsey, Austin D. Thompson, Mark N. Rigby, Greggory D. Boatright, William G. Pitt, Beverly L. Roeder, Scott C. Steffersen, Alonzo D. Cook May 2018

Baseline Effects Of Lysophosphatidylcholine And Nerve Growth Factor In A Rat Model Of Sciatic Nerve Regeneration After Crush Injury, Ryan L. Wood, Keaton S. Karlinsey, Austin D. Thompson, Mark N. Rigby, Greggory D. Boatright, William G. Pitt, Beverly L. Roeder, Scott C. Steffersen, Alonzo D. Cook

Faculty Publications

Schwann cells play a major role in helping heal injured nerves. They help clear debris, produce neurotrophins, upregulate neurotrophin receptors, and form bands of Büngner to guide the healing nerve. But nerves do not always produce enough neurotrophins and neurotrophin receptors to repair themselves. Nerve growth factor (NGF) is an important neurotrophin for promoting nerve healing and lysophosphatidylcholine (LPC) has been shown to stimulate NGF receptors (NGFR). This study tested the administration of a single intraneural injection of LPC (1 mg/mL for single LPC injection and 10 mg/mL for multiple LPC injections) at day 0 and one (day 7), two …