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Title: OPTIMAL BIDDING STRATEGY FOR HYDRO UNIT
Creator: Zhu, Renchen
Date: 2013-04-30, 2013-05
Description: The bidding price for the renewable energy is very different from some traditional energy, like gas, coal and so on, because when we produced...
Show moreThe bidding price for the renewable energy is very different from some traditional energy, like gas, coal and so on, because when we produced the renewable energy, the only cost is the generator unit cost, for example, wind power, water power and so on. People never need to pay the fuel price for the solar, water or wind. So here come one question how can we decide the energy price for these power. As we all know, the bidding price decided the profit for the generating company. Nowadays, more and more researches have been done in this field for every company want a good price to earn the highest profit. But for the renewable energy, they are different from the traditional energy which price is determined by the fuel price. So how to decide the bidding price of the renewable energy will be a good topic and question for us. To solve this problem, I will try to use an idea called minimum the imbalance in order to maximum the profit for those owners. This idea first has been applied in the wind unit. For my thesis, I will apply this idea to the hydro unit both with the storage and without storage. For each part, I will use some data to test. By these testing, the result will show this bidding strategy will be better.
M.S. in Electrical Engineering, May 2013
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Title: THERMODYNAMICS AND PHASE EQUILIBRIA OF HEUSLER ALLOYS
Creator: Chung, Yoonsung
Date: 2011-09, 2011-07
Description: Heusler compounds are of great interest for their properties such as shape memory, thermoelectric, ferromagnetic and spin polarization effects...
Show moreHeusler compounds are of great interest for their properties such as shape memory, thermoelectric, ferromagnetic and spin polarization effects that could lead to new mechanical and electronic devices. Currently, the study of Heusler alloys is focused on their electronic and magnetic properties, but the high temperature thermodynamic properties of these compounds have not been covered as much. A thorough knowledge of the thermodynamic properties and phase equilibria is required for developing this kind of alloys. This thesis is part of a systematic investigation of the thermodynamics and phase equilibria of ternary Heusler alloy systems. In this work, the high temperature reaction calorimeter was used to obtain the standard enthalpy of formation of compounds in the Ni2XSn (X = Ti, Zr, Hf, V and Nb) and Ni2TiX (X = Ga and In) ternary systems. It was confirmed the compound Ni2TaSn does not exist in the Heusler structure A Setaram Ligne 96 drop calorimeter was used to measure the heat content of Ni2TiSn as a function of temperature. Phase equilibria and crystal structures of Ni2TiSn, Ni2TiGa and Ni2TiIn were determined using XRD, SEM and EDS.
M.S. in Materials Science & Engineering, July 2011
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Title: ISOLATION OF MONOSPECIFIC ANTIBODY AGAINST SPLICED VARIANT OF DYSTROPHIN PROTEIN USING YEAST SURFACE DISPLAY TECHNIQUE
Creator: Saraswathi, Raj Prabu Vijayakumar
Date: 2011-05-04, 2011-05
Description: Dystrophin gene is the largest in the human genome with 79 exons covering greater than 0.1% of the total genome, located on the Xp21 locus of...
Show moreDystrophin gene is the largest in the human genome with 79 exons covering greater than 0.1% of the total genome, located on the Xp21 locus of the “X” chromosome resulting in a 427kDa protein, “Dystrophin”. Dystrophin is an important cytoskeletal protein which belongs to the β-Spectrin/α-actinin family of proteins. It comprises of an amino terminal domain, alpha helical coiled structure COOH domain, central rod region with 24 STRs and four proline rich hinge regions. It plays a vital role in localizing the Dystrophin glycoprotein complex (DGC) in the Sarcollema and is associated with the DGC in controlling the signaling events of certain proteins associated with DGC. The large size of the gene makes it more vulnerable to mutations resulting in partially functional or non-functional Dystrophin. The absence of Dystrophin results in disruption of sub sarcolemma-extracellular matrix linkage, loss of nitric oxide, progressive muscle weakening and muscle wasting leading to the death of patients typically before the end of their teenage. In certain cases alternatively spliced isoforms produce Dystrophin with reduced length yet stable and completely functionality. The main focus of this project was to select monospecific antibody against the more stable alternatively spliced variant D14 (15”16”) 17, which is functional and more stable compared to unspliced parent D14:17. The yeast surface display technique was used to effectively screen and select the yeast scFv clones containing the monospecific antibody against our target spliced variant D14 (15”16”) 17 protein and D2:3. The yeast scFv sub population was enriched by repeated MACS and FACS selection. Test colonies picked from the enriched scFv pool were confirmed via PCR and restriction digestion analysis. The scFv for the respective antigens were then sub cloned into pPnnl-9 secretion vector using YVH10 yeast cells via LiTRAFCO method. It was clear that by repeated MACS and FACS selection the scFv pool can be enriched and the yeast scFv clone sub population can be reduced to a significant level. The scFv sub cloned into Pnnl-9 secretion vector can be purified using affinity chromatography and the further affinity and avidity studies can be conducted.
M.S. in Biology, May 2011
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Title: L2E ESTIMATOR FOR THE CATEGORICAL MODEL WITH ELASTIC NET PENALTY
Creator: Wang, Yuan
Date: 2017, 2017-07
Description: The logistic regression model is an important generalized linear model for the categorical data. The maximum likelihood estimation is mostly...
Show moreThe logistic regression model is an important generalized linear model for the categorical data. The maximum likelihood estimation is mostly used in estimating the parameters of the logistic regression model. However, the maximum likelihood estimation is very sensitive to outliers which will cause the inaccuracies of the fitted parameters and model selection in high-dimensional regression. Chi and Scott (2014) demonstrated by simulation that minimizing the integrated square error or L2 estimation (L2E) is a robust method to fit 2-class categorical models. They also showed that the L2E estimation method can select the right model even in the presence of many outliers in high dimensional scenarios. In my thesis, I extended the L2E estimation method from 2-class to 3-class based on the MM algorithm by Chi and Scott (2014). Then I demonstrated the properties above for 2-class categorical models are also applicable to 3-class ones.
M.S. in Applied Mathematics, July 2017
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Title: PARAMETRIC IMAGE ESTIMATION IN ANALYZER-BASED PHASE CONTRAST IMAGING
Creator: Caudevilla, Oriol
Date: 2014, 2014-07
Description: Since the discovery of X-rays, by W.E. Roentgen in 1895, absorption-contrast imaging has been widely used in medical diagnostic, for example:...
Show moreSince the discovery of X-rays, by W.E. Roentgen in 1895, absorption-contrast imaging has been widely used in medical diagnostic, for example: mammography, chest X-ray, angiography etc. Over the last 25 years many researchers have shown that phase-contrast X-ray imaging is capable of obtaining a better contrast then classical absorption-contrast imaging. This is especially true in soft tissue imaging like mammography or at higher Xrays energies. During the past five years a significant effort has made in development of a tabletop analyzer-based phase-contrast system. In this system a perfect crystal is used to generate a quasi-monochromatic beam, which after interacting with an object is analyzed by a second perfect crystal called analyzer. The need of quasi-monochromatic beam and the low brilliance of conventional X-ray sources (CXS) has been the major limiting factor for tabletop systems. The work presents in this thesis aims to develop novel reconstruction methods for tabletop analyzer-based phase-contrast imaging (ABI) systems. The presented reconstruction methods goal is to minimize the impact of CXS low brilliance by utilizing phase-contrast image formation model and maximum or maximum-a-posteriori Poisson likelihood approach. Finally, a fast-convergent conjugate gradient optimization algorithm has been derived specifically for Poisson likelihood function maximization.
M.S. in Electrical Engineering, July 2014
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Title: An Alternative Car Show: An Alternateive Vehicle Insfrastructure
Creator: Hopkins, Kyle
Date: 2010-07-29

Title: Thermal conductivity
Creator: Bauer, W. Ernest, Jr
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/thermalconductiv00baue
Thesis (B.S.)--Armour Institute of Technology; Includes folded leaves in back pocket

Title: POWER ANALYSIS AND CONTROL OPTIMIZATION OF A HIGH GAIN RESONANT DC-DC CONVERTER
Creator: Wu, Haowen
Date: 2017, 2017-05
Description: Applications of DC-DC converter require a high power, high efficiency performance, especially for automotive applications and renewable energy...
Show moreApplications of DC-DC converter require a high power, high efficiency performance, especially for automotive applications and renewable energy applications. A desired converter should have a fast response, stable output in different conditions. This thesis studies a novel high gain DC-DC resonant converter and its control. Based on the circuit analysis and operation evaluation, feed-forward and feedback control methods are proposed in order to achieve stability under variety of changes. Moreover, circuit topology is investigated in response to the efficiency improvement. Simulations in PSIM, PLECS and MATLAB Simulink have been carried out to validate the controller design and topology development. The simulation results are in consistence to the theoretical analysis. The overall high efficiency at nominal operating point is further increased.
M.S. in Electrical Engineering, May 2017
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Title: RECEIVER AUTONOMOUS INTEGRITY MONITORING AGAINST ORBIT EPHEMERIS FAULTS IN CARRIER PHASE DIFFERENTIAL GPS
Creator: Stevanovic, Stefan
Date: 2013-04-18, 2013-05
Description: This work investigates the potential of the Global Positioning System (GPS) to enable a safe approach for rendezvous applications including...
Show moreThis work investigates the potential of the Global Positioning System (GPS) to enable a safe approach for rendezvous applications including shipboard landing of military aircraft. GPS has been shown to have the necessary accuracy for such an operation, and could potentially replace the existing radar or laser based systems. [Kha08][WPF08]1 However, to ensure safe operation, GPS must also be able to avoid hazardous situations. Shipboard aircraft approach navigation is an example rendezvous application requiring both high accuracy and high integrity. In this work, GPS measurement error models and orbit ephemeris fault (OEF) detection algorithms are developed for rendezvous applications, and performance is analyzed for the aircraft shipboard landing application. Both reference station and user based monitors can be used for orbit ephemeris fault detection. The available reference monitors either require a stationary reference receiver, or cannot protect against all types of orbit ephemeris faults. As an alternative, this work develops and investigates the use of receiver autonomous integrity monitoring (RAIM), which is user-based. Two contrasting algorithms, differential RAIM (DRAIM) and relative RAIM (RRAIM) are derived and analyzed for a realistic shipboard landing application. DRAIM is most effective when the aircraft first begins the approach. On the other hand, RRAIM performs best near the end of the approach. Assessing integrity risk is shown to be a major challenge for the RRAIM algorithm. Thus, a new unified RAIM (URAIM) concept is introduced. It seamlessly integrates DRAIM and RRAIM into a single detection algorithm, and also facilitates integrity risk evaluation. This is because the URAIM measurement equation can be used for both position estimation as well as fault detection. 1Corresponding to references in the Bibliography. xii Since high accuracy is desired, fixing integer cycle ambiguities is required. The Enforced Position-Domain Integrity-Risk Cycle Resolution Algorithm (EPIC) method of integrity risk bounding is used along with the URAIM fault detection algorithm in what we call the EPIC-URAIM algorithm. In general, the OEF will interfere with the cycle resolution process. In this work, the EPIC integrity risk bound formula is modified to account for the presence of an OEF. The EPIC-URAIM algorithm is simulated for 1507 sea-based locations around the globe. An average global availability of accuracy and integrity of 98.6% is achieved. This work illustrates the feasibility of detecting orbit ephemeris faults with integrity, while simultaneously meeting stringent accuracy requirements for real-time rendezvous navigation applications.
M.S. in Mechanical and Aerospace Engineering, May 2013
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Title: FABRICATION, CHARACTERIZATION AND RELEASE STUDIES OF LOW DENSITY POLYETHYLENE/CLAY NANOCOMPOSITES
Creator: Zhao, Ziqian
Date: 2015, 2015-07
Description: Nanocomposites exhibit enhanced physical properties including mechanical strength, thermal stability, and gas barrier properties. The...
Show moreNanocomposites exhibit enhanced physical properties including mechanical strength, thermal stability, and gas barrier properties. The development of nanocomposites has led to applications in food industry, mostly in food packaging. The application of nanocomposites in food packaging may extend the shelf life of a food, thus increasing the market value for manufactures. However, there is limited data and research to assess the risk of exposure of nanomaterials to consumers. This project aims at evaluating the factors that can influence the release of nanomateirals in low density polyethylene/clay nanocomposites films. Nanocomposites based on low density polyethylene (LDPE), containing 1, 3, 5 and 7 wt.% of Cloisite 20A and maleic anhydride-grafted polyethylene (MAPE) as a compatibilizer were prepared by melt compounding and characterized in this thesis project. Cloisite 20A is mostly composed of montmorillonite (MMT), which is commonly used as a nanoscale size filler. LDPE/Clay nanocomposite films containing MMT and three mass equivalents of MAPE were successfully extruded into thin films with good optical clarity. The materials were characterized by using transmission electron microscope (TEM), thermogravimetric analysis (TGA), oxygen permeation analysis and a material testing machine. Important properties such as tensile modulus, oxygen transmission rate, thermal resistance and glass transition temperature were measured. Nanocomposite films were immersed in three kinds of food simulants (absolute ethanol, 3% acetic acid and deionized water). Storage time, storage temperature and percent fill of clay were evaluated as the factors that can influence the release of nanomaterials. The content of released of Al, Mg, and Si was quantified using inductively coupled plasma mass spectrometry (ICP-MS). Mg, Al and Si were continuously released from nanocomposite films in duration of 30 days. Fastest releasing speed was found in 3% aqueous acid at 75 °C, and lower temperature can largely decrease the release of nanoparticles. This project is an initial attempt to assess the risks from the use of nanocomposites as food packaging.
M.S. in Food Safety and Technology, July 2015
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Title: SURVIVAL OF SALMONELLA ON CHAMOMILE, PEPPERMINT AND GREEN TEA DURING STORAGE RELATED TO TEMPERATURE AND HUMIDITY
Creator: Chen, Zhengzai
Date: 2013-04-24, 2013-05
Description: Botanical/herbal teas may contain antimicrobial compounds that will affect the survival and persistence of the native as well as contaminant...
Show moreBotanical/herbal teas may contain antimicrobial compounds that will affect the survival and persistence of the native as well as contaminant microflora. Although Salmonella are known for their ability to survive in low water activity environments, their survival on dry botanical/herbal teas has not been examined. The purpose of this work is to determine the survival of Salmonella on three types of teas, chamomile peppermint, and green tea under different storage conditions. In addition, the ability of Salmonella to grow in tea brewed with contaminated product was examined. A cocktail of four Salmonella serovars was inoculated onto 1 g samples of chamomile, peppermint, and green tea to give a starting cell population of approximately 10 log cfu/g. The inoculum was allowed to dry prior to storage at 25 °C and 35 °C and at low (<30% RH) and high (> 90% RH) humidity levels. At different time intervals up to 6 months, triplicate samples at each condition were evaluated for surviving Salmonella populations. In addition, samples were used to produce a low-temperature (sun) brewed tea and inoculated. Growth was assessed after 24 hr. Under the four storage conditions tested, survival followed the order 25°C/low RH > 35°C/low RH > 25°C/high RH > 35°C/high RH. Salmonella losses at 25°C/low RH occurred primarily during drying, after which populations showed little declines over 6 months. In contrast Salmonella decreased below detection after 45 days at 35°C and high RH in all teas tested. All teas tested supported the growth of Salmonella after brewing. Storage conditions significantly impact the survival of Salmonella in dried herbal teas. If Salmonella survives after storage, it may also survive and grow after a home brewing process.
M.S. in Food Safety and Technology, May 2013
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Title: IN VITRO STUDIES OF VIRULENCE SUPPRESSION ON P. AERUGINOSA BY PHOSPHATE / POLYPHOSPHATE-LOADED NANOPARTICLES
Creator: Yin, Yushu
Date: 2015, 2015-07
Description: Critically ill patients harbor multi-drug resistant pathogens that can activate their virulence in the response to low nutrient conditions and...
Show moreCritically ill patients harbor multi-drug resistant pathogens that can activate their virulence in the response to low nutrient conditions and host stress derived factors. It was recently shown that the oversupply of inorganic phosphate to bacterial environment can profoundly suppress the virulence of pathogens. Here we hypothesized that phosphateand/ or polyphosphate-loaded nanoparticles can present a tool to deliver and slowly release phosphate in pathogen-rich niche, thereby suppressing bacterial virulence. In this work, a designed study on effect of different phosphate levels (including the phosphate released from hydrogel nanoparticles) on virulence of P. aeruginosa is addressed. In this work, we developed formulations for preparing hexametaphosphate-loaded nanoparticles on the basis of that for phosphate loaded nanoparticles. We utilized inverse miniemulsion polymerization in the synthesis of these nanoparticles. Polyethylene glycol diacrylate (PEGDA, moleculat weight of 575 Da) and N-vinyl pyrrolidone (molecular weight: 111.14 Da ) were chosen to be the initial monomers because the main crosslinker, polyethylene glycol is a kind of biocompatible material that has been approved by the U.S. Food and Drug Administration (FDA). Several parameter could be adjusted among the experiment. We selected the monomer mole fraction of PEGDA-575 as our parameter. After the synthesis, a nanoparticle size distribution between 110 nm and 150 nm was obtained. And these nanoparticles were proved to be able to release phosphate and hexametaphosphate as drug molecules. Although there were release bursts in the test of release kinetics, the crosslink density could be adjusted in following researches. The second part of this study is to test the virulence suppression effect of the nanoparticles in in vitro experiment on a kind of opportunistic pathogen, P. aeruginosa. This kind of gram-negative bacteria is one of the common intestinal microbial communities. We presented the strategy of suppressing virulence while containing rather than killing the bacteria. As a result, polyphosphate loaded nanoparticles showed to be the most effective one among several experiment groups. This result gave this study a promising future in further research in several aspects, such as in vivo test in biomedical and biomedical engineering.
M.S. in Chemical Engineering, July 2015
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Title: PHASE EQUILIBRIA AND THERMODYNAMIC MEASUREMENTS OF SOME HEUSLER COMPOUNDS
Creator: Chen, Song
Date: 2012-08-14, 2012-07
Description: Heusler alloys are compounds based on the original Heusler phase Cu2MnAl which are ternary intermetallics with a particular chemical...
Show moreHeusler alloys are compounds based on the original Heusler phase Cu2MnAl which are ternary intermetallics with a particular chemical stoichiometric formula X2YZ and face-centered cubic structure. Heusler alloys are of interest because of a range of physical phenomena which may occur in them that can be applied in mechanical or electronic devices, including shape memory property and disorder/order phenomenon. In this work, a high temperature drop calorimeters and Setaram calorimeters were used to obtain the enthalpy of formation and heat capacity of compounds in the Mn-based Heusler compounds (X2MnZ). Lattice parameters of these compounds were determined with XRD, and phase equilibria in these alloy system were studied in this work. Phase transformations were studied with DSC and dilatometry. The work is aimed at populating databases for computational thermodynamics, developing an understanding of alloying and clarifying phase equilibria.
M.S. in Material Science and Engineering, July 2012
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Title: Thermostatic temperature control for gas engine jacket water
Creator: Gross, Morton G, Steiner, Albert J.
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/thermostatictemp00gros
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 3-4

Title: The yield of acetic acid as influenced by temperature in wood distillation
Creator: Marx, Walter L.
Date: 2009, 1913
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/yieldofaceticaci00marx
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 22

Title: IN VITRO ASSAYS FOR ASSESSING THE IMPACT OF PROCESSING ON THE ALLERGENIC POTENTIAL OF MILK ALLERGENS
Creator: Zhao, Yuhui
Date: 2014, 2014-07
Description: A better understanding of how processing may affect the allergenicity of proteins will allow a more accurate allergen risk assessment and...
Show moreA better understanding of how processing may affect the allergenicity of proteins will allow a more accurate allergen risk assessment and achieve a greater success in food allergy management. To determine whether food processing can affect the allergenic potential of proteins, immunochemical methods are commonly used, however, these methods are not able to determine changes in the proteins’ ability to elicit allergic reactions. Although food challenge studies are the gold standard for determining the allergenicity of proteins, such studies are seldom performed due to ethical reasons and the difficulty in recruiting a sufficient number of study participants. In recent years, a number of mediator release assays have been developed to measure the allergenic potential of food proteins in vitro. How these cell-based assays can be used to assess the impact of thermal or other processing conditions on the allergenic potential of proteins remains to be determined. This study evaluated the use of sensitized rat basophilic leukemia (RBL) cells for assessing the impact of boiling on the allergenic potential of milk allergens by measuring changes in the proteins’ ability to induce cell degranulation and the release of β-hexosaminidase. RBL-2H3 cells sensitized with rat IgEs that were specifically raised against NIST non-fat milk standard reference material, β-lactoglobulin (BLG), α-lactalbumin (ALA) and α-casein (αCAS) were challenged with various concentrations of each allergen in its native and processed (boiled in PBS for 10 min) forms. Cell degranulation caused by the allergen was monitored by measuring the release of β-hexosaminidase. All allergens (NIST milk, BLG, ALA, and αCAS) were able to induce the release of β-hexosaminidase, up to 43.1%. A decrease in % release of β-hexosaminidase was observed when cells were challenged with a decreasing concenration xi of the ALA and milk allergens. Boiling of nonfat milk, ALA, BLG and αCAS caused an increase in the % release of β-hexosaminidase from sensitized cells across antigen concentrations from 10-6 mg/mL to 1 mg/mL. In conclusion, this study demonstrated that the in vitro mediator release assay method may serve as a useful model to evaluate the impact of thermal processing on the allergenic potential of milk allergens.
M.S. in Food Safety and Technology, July 2014
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Title: FINFET BASED STANDARD CELL LIBRARY CHARACTERIZATION
Creator: Yuan, Yu
Date: 2015, 2015-07
Description: In this work, four standard cell libraries based on FinFET technology have been characterized and implemented. The first library uses the BSIM...
Show moreIn this work, four standard cell libraries based on FinFET technology have been characterized and implemented. The first library uses the BSIM-CMG and PTM-MG models, which represents the common multi-gate devices. Two libraries are based on the BSIM-IMG model, operating in short-gate (corresponding to low-Vt) mode and lowpower (corresponding to high-Vt) mode separately. Synthesis and simulation of BSIMCMG based library is presented and compared to the conventional 45nm CMOS library, FreePDK45. The results show acceptable accuracy of the library based on BSIM-CMG model. For the libraries based on BSIM-IMG model, Short-Gate (SG) mode, Low-Power (LP) mode and the mixed-mode (combining both SG and LP modes) have been analyzed. The results proved that the low-power independent multi-gate FinFET can be used for leakage power reduction, just like the bulk CMOS high-Vt devices. At the end of this work, another library based on CCS model was characterized and verified, which show far better accuracy in terms of both timing and power modeling.
M.S. in Electrical Engineering, July 2015
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Title: PREPARATION FOR IMPLANTATION OF AN INTRACORTICAL VISUAL PROSTTIESIS IN A HUMAN: WORKING TOWARDS SATURATION
Creator: Troyk, Melissa J
Date: 2017, 2017-07
Description: The research focused on restoring visual perception via a vision prosthetic is progressing at a rapidly advancing rate. Previous research on...
Show moreThe research focused on restoring visual perception via a vision prosthetic is progressing at a rapidly advancing rate. Previous research on the experiences and perspectives of past, current, and potential vision prosthesis users has demonstrated that the decision to obtain a vision prosthetic is driven by a variety of unique factors and variables that merge with one another during the process of deciding to participate in clinical vision prosthesis research (Lane, Huyck, Troyk, & Schug, 2012; Lane, Nitsch, Huyck, Troyk, & Schug, 2014; Lane, Nitsch, & Troyk, 2015). The purpose of the current study was twofold: 1) to determine if our understanding of the experiences and perspectives of potential vision prosthesis users was nearing saturation, and 2) to understand the perspectives of potential vision prosthesis users who are veterans. Data were analyzed in accordance with qualitative analysis procedures. Results identified several new themes and subthemes that were determined to be important to our understanding of potential users’ perspectives of an intracortical vision prosthesis device. A preliminary framework is proposed for understanding how the identified themes and subthemes merge during the process of deciding to participate in an experimental vision prosthesis human clinical trial. The results demonstrated that while progress has been made, there is still more to learn about blind individuals’ perspectives of vision prostheses and how they would decide to participate in vision prosthesis research.
M.S. in Psychology, July 2017
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Title: Functionalized Polyoxovanadates: Synthesis, Characterization and Properties
Creator: Zheng, Yujuan
Date: 2012-04-30, 2011-12
Description: The compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom...
Show moreThe compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom in place of a single oxygen atom in each of the six vanadium-oxygen octahedra. Attached to each nitrogen are two alkoxide arms (-O-C-C-) which terminate on separate oxygen atoms of the octahedra. A third ethoxy group (-CH2-CH2-OH) dangles freely from each nitrogen atom. The functionalized cationic core [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]+ is generated in situ and is cationic with a charge of +1. Chloride is the counteranion. Each vanadium addenda atom is the +4 oxidation state, and the six unpaired electrons result in interesting magnetic properties. C0 is obtained by reaction of a vanadium oxide source triethanolamine. The purpose of the research described here was to adapt the synthetic protocol associated with triethanolamine to other similar ligands. Ligand choice was motivated by the broader goal of this research group to form (extended) hybrid electronic and magnetic materials by chemically bonding POM cores to chemically interesting ligands, such as dyes or other POM cores. In this regard, the original triethanolamine derivative has a number of shortcomings; chief among them is the inaccessibility of the alcoholic functional group chemistry---due to its low pH---that otherwise might have been used to form linkages through the dangling alkoxy arms. Additionally, linkages containing paraffinic carbon (-C-C-), which is not a good conduit of electronic interaction, are chemically undesirable where the synthetic goal is hybrid structures with interesting electronic and magnetic properties. The results associated with the three ligands, diethanolamine, N,N'-Bis(2-hydroxyethyl)ethylenediamine, and N,N-Bis(2-hydroxyethy) ethylenediamine, are described herein. Diethanolamine was chosen because---based on a structural comparison to triethanolamine---it was expected to produce a structure having a hydrogen atom in place of the dangling ethoxy arms, which was indeed the result. We considered this structure highly desirable becasue of the potential lability of the hydrogen atom (-N-H), which would allow us to functionalist the core directly. The resulting compounds are characterized by single-crystal X-ray diffraction, elemental analysis, mass spectroscopy, thermogravimetric analysis, FT-IR and UV-Vis spectroscopy, maganometric titration, temperature-dependent magnetic susceptibility measurements, and cyclic voltammetry. The results of the cyclicvoltammetric investigation are consistent with the labile hydrogen atom (-N-H).
M.S. in Chemistry, December 2011
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Title: MULTIPLE-INPUT MULTIPLE-OUTPUT NONLINEAR CONTROL OF SELECTIVE CATALYTIC REDUCTION SYSTEMS
Creator: Dong, Siwei
Date: 2015, 2015-05
Description: Selective catalytic reduction (SCR) is one of the most promising solutions to meet the future nitrogen oxides (NOx) emissions regulations for...
Show moreSelective catalytic reduction (SCR) is one of the most promising solutions to meet the future nitrogen oxides (NOx) emissions regulations for heavy-duty diesel vehicles. However, such vehicles often operate in highly transient operations in which mobile selective catalytic reduction systems encounter significant efficiency challenges, especially when the engine is under a low load. A detailed simulation model of the SCR system was developed in the Gamma Technologies simulation suite and a baseline model of feedback control on SCR was constructed. Experiment data for the exhaust gas composition and conditions from a Cummins ISB engine was used to provide the input parameters for the SCR model. The results reveal that in the low-load conditions, the efficiency of NOx reduction in the SCR system is very low, and the level NOx concentration exiting the vehicle could be over 5 times than the limitation set by the US Environmental Protection Agency (EPA). However, these issues are encountered in part due to the fact that current SCR controls focus solely on the aftertreatment components and treat the incoming engine output conditions as system disturbances. To address the low NOx conversion problems encountered in low load conditions, a new integrated engine and aftertreatment control model was designed. This integrated approach improves the SCR system efficiency by using available feedback and modulating the upstream air/fuel ratio to provide more favorable SCR inlet conditions. From experiment data analysis, the engine’s air/fuel ratio is shown to have a critical impact on exhaust gas temperature and exhaust oxygen fraction, which highly affect the SCR reactions. In order to integrate the engine and aftertreatment system, a model of the SCR dynamics was created and validated and a simple model of the relationship between the engine’s air/fuel ratio and resulting exhaust temperature and composition is leveraged. The new model-based control strategy is proven to be effective to improve SCR system performance at low-load operations. With a small value shift in air/fuel ratio, the efficiency of low-load SCR system can increase from 40% to 85% at low load operating conditions.
M.S. in Mechanical and Aerospace Engineering, May 2015
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