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Combined Model Predictive Control And Scheduling With Dominant Time Constant Compensation, Logan Beal, Junho Park, Damon Petersen, Sean C. Warnick, John Hedengren 2017 Brigham Young University

Combined Model Predictive Control And Scheduling With Dominant Time Constant Compensation, Logan Beal, Junho Park, Damon Petersen, Sean C. Warnick, John Hedengren

All Faculty Publications

Linear model predictive control is extended to both control and optimize a product grade schedule. The proposed methods are time-scaling of the linear dynamics based on throughput rates and grade-based objectives for product scheduling based on a mathematical program with complementarity constraints. The linear model is adjusted with a residence time approximation to time-scale the dynamics based on throughput. Although nonlinear models directly account for changing dynamics, the model form is restricted to linear differential equations to enable fast online cycle times for large-scale and real-time systems. This method of extending a linear time-invariant model for scheduling is designed for ...


Crystal Engineering Of Active Pharmaceutical Ingredients With Low Aqueous Solubility And Bioavailability, Jenna M. Skieneh 2017 The University of Western Ontario

Crystal Engineering Of Active Pharmaceutical Ingredients With Low Aqueous Solubility And Bioavailability, Jenna M. Skieneh

Electronic Thesis and Dissertation Repository

Approximately 75% of new molecular entities approved by the Food and Drug Administration (FDA) for use in the pharmaceutical industry are found to have poor aqueous solubility. This undesirable attribute leads to consequences such as higher doses required to reach therapeutic levels, greater vulnerability to food effects, lesser fraction absorbed in the small intestine and damage to the environment due to increased quantity of excretion. The addition of an excipient (i.e. a FDA approved inactive ingredient) to the molecular structure of an active pharmaceutical ingredient (API) through intermolecular bonding is of growing interest because the properties of the API ...


Performance Characterization Of Coagulation Pretreatment For Two Industrial Effluents, Jing Wan 2017 The University of Western Ontario

Performance Characterization Of Coagulation Pretreatment For Two Industrial Effluents, Jing Wan

Electronic Thesis and Dissertation Repository

In this work, performances of coagulation and flocculation were tested for two different industrial effluents. Coagulation-Flocculation and activated carbon adsorption were applied for the remediation of oil sands process-affected water (OSPW), generated from oil sands operations in Alberta, Canada. OSPW is a complex mixture of suspended solids, various suspended and dissolved organic compounds. Alum and natural coagulant Opuntia ficus-indica (OFI) were used as the coagulants, and the process was optimized to improve the removal of turbidity and dissolved organic carbon (DOC). The maximum removal of 98% and 63% in turbidity and DOC from OSPW, respectively occurred at pH=6.32 ...


Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca G. Ong, David B. Hodge 2017 Michigan State University

Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca G. Ong, David B. Hodge

Rebecca Ong

Background

Heterogeneity within herbaceous biomass can present important challenges for processing feedstocks to cellulosic biofuels. Alterations to cell wall composition and organization during plant growth represent major contributions to heterogeneity within a single species or cultivar. To address this challenge, the focus of this study was to characterize the relationship between composition and properties of the plant cell wall and cell wall response to deconstruction by NaOH pretreatment and enzymatic hydrolysis for anatomical fractions (stem internodes, leaf sheaths, and leaf blades) within switchgrass at various tissue maturities as assessed by differing internode.

Results

Substantial differences in both cell wall composition ...


Enhanced Oxidation Of Organic Contaminants By Ferrate: Acid-Activated And Silica Gel-Enhanced Ferrate(Vi) Oxidation Processes, Kyriakos Manoli 2017 The University of Western Ontario

Enhanced Oxidation Of Organic Contaminants By Ferrate: Acid-Activated And Silica Gel-Enhanced Ferrate(Vi) Oxidation Processes, Kyriakos Manoli

Electronic Thesis and Dissertation Repository

Recently, the tetraoxy high-valent iron(VI), known as ferrate(VI) (Fe(VI); FeVIO42), received a great attention as a water-treatment chemical, because of its unique oxidation, disinfection, and coagulation properties. Though Fe(VI) has shown remarkable efficiency in oxidizing several pollutants in water, it has sluggish reactivity with some emerging organic contaminants, especially at basic pH conditions. Thus, the main objective of this PhD thesis was to activate or catalyze Fe(VI) oxidation reactions, at mild alkaline pH conditions, to enhance the oxidative transformation of organic pollutants and reduce the required dosage of Fe(VI) and ...


Regeneration Potential Of Activated Petroleum Coke For Application In Oil Sands Process-Affected Water, Sreejon Das 2017 The University of Western Ontario

Regeneration Potential Of Activated Petroleum Coke For Application In Oil Sands Process-Affected Water, Sreejon Das

Electronic Thesis and Dissertation Repository

Cost effective regeneration of spent adsorbent is crucial for large scale application of adsorption as a viable separation process. While adsorption studies are abundant in literature, systematic and comprehensive regeneration studies are seldom reported in open literature. A proprietary activated carbon from petroleum coke was used for the removal of model naphthenic acids (NAs) and organic compounds from oil sands process-affected water (OSPW). A systematic and comprehensive study was conducted to regenerate the adsorbents. Methanol with aqueous NaOH (pH adjusted to around 12) was applied to regenerate the spent commercially available granular activated carbon (GAC) and activated petroleum-coke (APC). Optimization ...


Surface Tension, Interfacial Tension And Phase Behavior: Interactions Of Surfactant/Polymer Solutions With Crude Oil, Michael A. Steinerd, Jaeyub Chung, Bryan W. Boudouris, Nathan C. Schultheiss, Elias I. Franses 2017 Purdue University

Surface Tension, Interfacial Tension And Phase Behavior: Interactions Of Surfactant/Polymer Solutions With Crude Oil, Michael A. Steinerd, Jaeyub Chung, Bryan W. Boudouris, Nathan C. Schultheiss, Elias I. Franses

The Summer Undergraduate Research Fellowship (SURF) Symposium

Advanced oil recovery techniques, beyond primary and secondary recovery, are required in order to produce additional oil in existing reservoir rock. Here, we evaluated a combination of polymer and surfactant aqueous solutions, in order to generate a working fluid capable of achieving high-performance enhanced oil recovery (EOR). In this recovery process, surfactant is added to the water flooding mixture in order to lower the interfacial tension between the oil and the water. If the interfacial tension can be decreased by ~1,000-fold, then the aqueous solution can mobilize and displace the oil. Moreover, a polymer is added to the aqueous ...


Modeling The Aqueous-Phase Copper Ion-Exchange Behavior Onto Ssz-13 Zeolites, Brian N. Bayer, Rajamani Gounder, Trevor M. Lardinois 2017 Purdue University

Modeling The Aqueous-Phase Copper Ion-Exchange Behavior Onto Ssz-13 Zeolites, Brian N. Bayer, Rajamani Gounder, Trevor M. Lardinois

The Summer Undergraduate Research Fellowship (SURF) Symposium

Copper-exchanged zeolites are utilized as catalysts for the selective catalytic reduction of nitrogen oxides, which are atmospheric pollutants found in diesel engine exhaust. The total amount of copper ions and the types of copper species (Cu(II) or Cu(II)OH) exchanged onto a zeolite can be varied. Copper is exchanged onto SSZ-13 (an aluminosilicate zeolite with the chabazite topology) during a process known as aqueous ion exchange, where the zeolite is mixed in a copper-containing solution. The distribution of copper on SSZ-13 is influenced by exchange conditions, including the molarity, temperature, and pH of the copper solution. The effect ...


Metabolic Comparison Of Wild-Type And Transgenic Synechocystis Pcc 6803 Cyanobacteria, Ian A. McLuckey, John A. Morgan, Joel Yu King Hing 2017 Purdue University

Metabolic Comparison Of Wild-Type And Transgenic Synechocystis Pcc 6803 Cyanobacteria, Ian A. Mcluckey, John A. Morgan, Joel Yu King Hing

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Calvin-Benson (CBB) cycle is an essential part of nature. This phenomenon allows carbon molecules in carbon dioxide from the atmosphere to be converted into useful energy in the form of sugars. Cyanobacteria are single-celled organisms capable of utilizing energy from sunlight to drive this cycle and are also readily engineered. In hopes of improving this cycle, we compared a wild-type version of the Synechocystis PCC6803 cyanobacteria to an engineered version overexpressing the enzyme FBA (fructose-biphosphate aldolase), called 70 glpX, to deduce how the overexpressing strain is able to be more photosynthetically efficient. To do this, comparative metabolomics were done ...


Capsule-Based Dropwise Additive Manufacturing With Pharmaceutical Suspensions, Kaitlyn N. Buck, Andrew J. Radcliffe, Gintaras V. Reklaitis 2017 Purdue University

Capsule-Based Dropwise Additive Manufacturing With Pharmaceutical Suspensions, Kaitlyn N. Buck, Andrew J. Radcliffe, Gintaras V. Reklaitis

The Summer Undergraduate Research Fellowship (SURF) Symposium

Current manufacturing of pharmaceutical products focuses on creating a standard dosage of the active pharmaceutical ingredient (API); however, dosages often need to be altered or customized to account for a patient’s age, weight, comorbidity, and other genetic factors. A potential method for dispensing precise dosages of API suspensions through dropwise addition is detailed in the following paper. By using a drop-on-demand printing rig, a series of suspensions comprised of varying volume fractions of a micron-scale API in a carrier fluid were printed, and individual drop volumes were analyzed using high-resolution imaging. From this, capsules with 1 mg dosages and ...


Carbon Removal And Optoelectronic Property Tuning In Copper Arsenic Sulfide Thin Films Through Ligand Exchange And Alloying, Louis R. Schroeder, Scott McClary, Rakesh Agrawal 2017 Purdue University

Carbon Removal And Optoelectronic Property Tuning In Copper Arsenic Sulfide Thin Films Through Ligand Exchange And Alloying, Louis R. Schroeder, Scott Mcclary, Rakesh Agrawal

The Summer Undergraduate Research Fellowship (SURF) Symposium

Solution processed thin film solar cells are attractive alternatives to conventional energy sources due to low waste generation, flexibility in substrate choice, and scalability. The novel semiconductor Cu3AsS4 in the enargite phase has a near ideal band gap of 1.4 eV and has earth abundant constituent elements; yet single-junction solar cells have yielded low efficiencies due to a secondary carbonaceous phase present, among other issues. This carbonaceous phase may be eliminated by exchanging the carbonaceous ligands with molecular metal chalcogenides. To characterize the ligand exchanged particles, UV-Vis-NIR spectroscopy, Raman spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy ...


Modal Phonon Transport Across Interfaces By Non-Equilibrium Molecular Dynamics Simulation, Yang Zhong, Tianli Feng, Xiulin Ruan 2017 Purdue University

Modal Phonon Transport Across Interfaces By Non-Equilibrium Molecular Dynamics Simulation, Yang Zhong, Tianli Feng, Xiulin Ruan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Phonons represent the quantization of lattice vibration, responsible for heat transfer in semiconductors and dielectrics. Phonon heat conduction across interfaces is crucially important for the thermal management of real-life devices such as smartphones, electric vehicles, and satellites. Although recent studies have broadly investigated spectral phonon contribution to lattice thermal conductivity, the mechanism of phonon modal transport across interfaces is still not well-understood. Previous models, including the acoustic mismatch model (AMM) and diffuse mismatch model (DMM), only consider elastic process while neglecting inelastic phonon contributions. Herein, we employ spectral Non-Equilibrium Molecular Dynamics Simulation (NEMD) to probe the temperature and heat flux ...


Separation Of Rare Earth Elements From Aluminum Using Ion-Exchange Chromatography, Shabrina Nurfitriani, Hoon Choi, Nien-Hwa Linda Wang 2017 Purdue University

Separation Of Rare Earth Elements From Aluminum Using Ion-Exchange Chromatography, Shabrina Nurfitriani, Hoon Choi, Nien-Hwa Linda Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Demand of rare earth elements (REEs) has increased tremendously due to their key roles in electronics and emerging technology. Recently, new technology was developed at Purdue to extract REEs from coal fly ash. This study is focused on the separation of aluminum ions (Al), a major impurity in the extract, from REEs. The goal is to test the feasibility of an ion-exchange process for separating REEs from a highly-concentrated Al solution. First, we reduced the resin particle size to decrease dispersion and diffusion effects, to increase resin productivity, and to reduce the amounts of REEs and the ion-exchange resin required ...


Cell-Free Synthesis Of Proteins With Unnatural Amino Acids: Exploring Fitness Landscapes, Engineering Membrane Proteins And Expanding The Genetic Code, Song Min Schinn 2017 Brigham Young University

Cell-Free Synthesis Of Proteins With Unnatural Amino Acids: Exploring Fitness Landscapes, Engineering Membrane Proteins And Expanding The Genetic Code, Song Min Schinn

All Theses and Dissertations

Unnatural amino acids (uAA) expand the structural and functional possibilities of proteins. Numerous previous studies have demonstrated uAA as a powerful tool for protein engineering, but challenges also remain. Three notable such challenges include: (1) the fitness of uAA-incorporated proteins are difficult to predict and time-consuming to screen with conventional methods, (2) uAA incorporation in difficult-to-express proteins (e.g. membrane proteins such as G-protein coupled receptors) remain challenging, and (3) the incorporation of multiple types of uAA are still limited. In response, we pose cell-free protein synthesis (CFPS), a rapid and versatile in vitro expression system, as a platform to ...


Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca G. Ong, David B. Hodge 2017 Michigan State University

Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca G. Ong, David B. Hodge

Department of Chemical Engineering Publications

Background

Heterogeneity within herbaceous biomass can present important challenges for processing feedstocks to cellulosic biofuels. Alterations to cell wall composition and organization during plant growth represent major contributions to heterogeneity within a single species or cultivar. To address this challenge, the focus of this study was to characterize the relationship between composition and properties of the plant cell wall and cell wall response to deconstruction by NaOH pretreatment and enzymatic hydrolysis for anatomical fractions (stem internodes, leaf sheaths, and leaf blades) within switchgrass at various tissue maturities as assessed by differing internode.

Results

Substantial differences in both cell wall composition ...


Batch And Fed Batch Cultivation And Harvesting Of Nannochloropsis Gaditana For Environmental Applications, Roopa P. Devasya 2017 The University of Western Ontario

Batch And Fed Batch Cultivation And Harvesting Of Nannochloropsis Gaditana For Environmental Applications, Roopa P. Devasya

Electronic Thesis and Dissertation Repository

Two challenging problems facing our world are the exhaustion of fossil fuels and climate change. Microalgae are eukaryotic phototrophs or prokaryotic cyanobacteria (blue green algae) that are able to capture CO2 and produce lipids suitable for biodiesel, thus can mitigate these challenges. The potential application of microalgae biomass for biofuel production is a clean and sustainable approach to replace fossil fuels. An important consideration for reducing the cost of biofuel is the economical production of algal biomass with high lipid yields. In this study, the marine microalgae Nannochloropsis gaditana were investigated for biomass and lipid production using two ...


Particle Deposition Behavior From Coal-Derived Syngas In Gas Turbines At Modern Turbine Inlet Temperatures, Robert Laycock 2017 Brigham Young University

Particle Deposition Behavior From Coal-Derived Syngas In Gas Turbines At Modern Turbine Inlet Temperatures, Robert Laycock

All Theses and Dissertations

Certain types of fuel used for combustion in land-based gas turbines can contain traces of ash when introduced into a gas turbine. Examples include synfuel, from the gasification of coal, and heavy fuel oil. When these ash particles travel through the hot gas path of the gas turbine they can deposit on turbine vanes and blades. As deposits grow, they can reduce turbine efficiency and damage turbine hardware. As turbine inlet temperatures increase, ash deposition rates increase as well.Experiments were conducted in the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University to better understand ash deposition behavior at ...


Enhancing Co-Water Mass Transfer By Functionalized Mcm41 Nanoparticles, Haiyang Zhu, Brent H. Shanks, Theodore J. Heindel 2017 Iowa State University

Enhancing Co-Water Mass Transfer By Functionalized Mcm41 Nanoparticles, Haiyang Zhu, Brent H. Shanks, Theodore J. Heindel

Theodore J. Heindel

Organic groups are grafted to ∼250-nm-diameter MCM41 nanoparticles with a spherical morphology to enhance the CO-water volumetric mass-transfer coefficient (kLa) for synthesis gas fermentation. The results indicate that (i) ∼250-nm MCM41 nanoparticles show a higher kLa value than large silica particles (1.4 and 7 μm), (ii) surface hydroxyl groups on MCM41 nanoparticles play an important role in mass-transfer enhancement, (iii) organic groups grafted to MCM41 modify the mass-transfer enhancement, and (iv) mercaptan groups grafted to MCM41 show the most mass-transfer enhancement of ∼1.9 times that of no nanoparticle addition. The CO-water mass-transfer enhancement depends on the interaction between ...


Effect Of Electrolytes On Co-Water Mass Transfer, Haiyang Zhu, Brent H. Shanks, Theodore J. Heindel 2017 Iowa State University

Effect Of Electrolytes On Co-Water Mass Transfer, Haiyang Zhu, Brent H. Shanks, Theodore J. Heindel

Theodore J. Heindel

The influence of various electrolytes such as sulfate, nitrate, and chloride on CO-water mass transfer was investigated in this study. The results indicate that the enhancement in the CO-water volumetric masstransfer coefficient ranged from 1.5 to 4.7 times that of a baseline system without electrolytes, depending on electrolyte type and concentration. For those electrolytes with the same anions, copper-containing electrolytes provided stronger enhancement, whereas for those electrolytes with the same cations, sulfate-containing electrolytes showed stronger enhancement. By measuring both the CO-water volumetric mass-transfer coefficient (kLa) and the mass-transfer coefficient (kL), it was found that the electrolytes inhibit gas ...


High Throughput Characterization Of Adult Stem Cells Engineered For Delivery Of Therapeutic Factors For Neuroprotective Strategies, Anup D. Sharma, Pavel A. Brodskiy, Emma M. Petersen, Melih Dagdeviren, Eun-Ah Ye, Surya K. Mallapragada, Donald Sakaguchi 2017 Iowa State University

High Throughput Characterization Of Adult Stem Cells Engineered For Delivery Of Therapeutic Factors For Neuroprotective Strategies, Anup D. Sharma, Pavel A. Brodskiy, Emma M. Petersen, Melih Dagdeviren, Eun-Ah Ye, Surya K. Mallapragada, Donald Sakaguchi

Surya K Mallapragada

Mesenchymal stem cells (MSCs) derived from bone marrow are a powerful cellular resource and have been used in numerous studies as potential candidates to develop strategies for treating a variety of diseases. The purpose of this study was to develop and characterize MSCs as cellular vehicles engineered for delivery of therapeutic factors as part of a neuroprotective strategy for rescuing the damaged or diseased nervous system. In this study we used mouse MSCs that were genetically modified using lentiviral vectors, which encoded brain-derived neurotrophic factor (BDNF) or glial cell-derived neurotrophic factor (GDNF), together with green fluorescent protein (GFP).

Before proceeding ...


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