Other Chemical Engineering Commons^™

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO₂-supplemented raceway ponds, each with a 33-m² surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …

Inhalable Nanocomposites And Anticancer Agents For Cancer Therapy, Nathanael A. Stocke

Theses and Dissertations--Chemical and Materials Engineering

Cancer is designated as the leading cause of mortality worldwide and lung cancer is responsible for nearly 30% of all cancer related deaths. Over the last few decades mortality rates have only marginally increased and rates of recurrence remain high. These factors, among others, suggest the need for more innovative treatment modalities in lung cancer therapy. Targeted pulmonary delivery is well established for treating pulmonary diseases such as asthma and provides a promising platform for lung cancer therapy. Increasing local deposition of anticancer agents (ACAs) and reducing systemic exposure of these toxic moieties could lead to better therapeutic outcomes and …

In-Package Nonthermal Plasma Degradation Of Pesticides On Fresh Produce, N. Misra, Shashi Pankaj, Tony Walsh, Finbarr O'Regan, Paula Bourke, Patrick J. Cullen

Articles

In-package nonthermal plasma (NTP) technology is a novel technology for the decontamination of foods and biological materials. This study presents the first report on the potential of the technology for the degradation of pesticide residues. A cocktail of pesticides, namely Azoxystrobin, Cyprodinil, Fludioxonil and Pyriproxyfen was tested on strawberries. The concentrations of these pesticides were monitored in priori and post- plasma treatment using GC-MS/MS. An applied voltage and time dependent degradation of the pesticides was observed for treatment voltages of 60, 70 and 80 kV and treatment durations ranging from 1 to 5 min, followed by 24 h in-pack storage. …

Combining Monte Carlo Transport And Level Set Surface Evolution For Modeling Vapor Phase Deposition Of Thin Films Over Sub-Micron Features, John Lewis Smith

Graduate Theses - Chemical Engineering

A hybrid scheme is used to model the vapor phase deposition of thin films at the feature scale. The transport of the chemical species to the substrate surface is modeled with a Collisionless Direct Simulation Monte Carlo (DSMC) method. The Level Set Method is used to model the growth of the thin-film on the substrate. The convergence criteria for these methods were not found in literature.

The governing equations for the Level Set Method are, in general, non-linear partial differential equations. The coupling of the DSMC Method with the Level Set Method results in a set of non-Gaussian stochastic non-linear …

Electrospinning Applications Air Filtration And Superhydrophobic Materials, Negar Ghochaghi, Adetoun Taiwo

Graduate Research Posters

Electrospinning is a widely applicable technique that generates non-woven fibers in the micro and nano range. In this project two of its applications are highlighted namely filtration media and enhancement of wettability. The first project demonstrates that electrospinning can be used to produce new fiber filtration media with controlled microstructure. The bimodal and unimodal orthogonal and random filters were made and characterized against their filtration efficiency and pressure drop. Figure of Merit (FOM) was also calculated and discussed. It is shown that the FOM increases when the electrospun fibers are arranged into alternating layers of aligned course and fine fibers. …

Multiscale Modeling Of Enzyme-Catalyzed Methanol Production By Particulate Methane Monooxygenase, Katherine K. Bearden

Doctoral Dissertations

In this work, the conversion of methane to methanol by the particulate Methane Monooxygenase (pMMO) enzyme is investigated using a multi-scale modeling approach. This enzyme participates in carbon cycling and aids in the removal of harmful atmospheric methane, converting it to methanol. The interaction between pMMO and a neighboring enzyme that is present in the same organism is studied, and the unknown pMMO active site is elucidated and tested for methane oxidation towards the production of methanol.

Fundamental knowledge of pMMO's mechanism is not fully understood. Understanding how this enzyme works in nature will provide information towards designing efficient synthetic …

Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. J. Metting, Johnathan K. Bunn, Ellen A. Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason R. Hattrick-Simpers

Faculty Publications

A gradient annealing cell has been developed for the high-throughput study of thermalannealing effects on thin-film libraries in different environments. The inexpensive gradientannealing unit permits temperature gradients as large as 28 °C/mm and can accommodate samples ranging in length from 13 mm to 51 mm. The system was validated by investigating the effects of annealing temperature on the crystallinity, resistivity, and transparency of tin-doped indium oxide deposited on a glass substrate by magnetron sputtering. The unit developed in this work will permit the rapid optimization of materials properties such as crystallinity, homogeneity, and conductivity across a variety of applications.

Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers

Faculty Publications

High throughput (combinatorial) materials science methodology is a relatively new research paradigm that offers the promise of rapid and efficient materials screening, optimization, and discovery. The paradigm started in the pharmaceutical industry but was rapidly adopted to accelerate materials research in a wide variety of areas. High throughput experiments are characterized by synthesis of a “library” sample that contains the materials variation of interest (typically composition), and rapid and localized measurement schemes that result in massive data sets. Because the data are collected at the same time on the same “library” sample, they can be highly uniform with respect to …

Cloning And Characterization Of Sas0754, A Hypothetical Protein From Community Associated Staphylococcus Aureus, Unknown Unknown

Symposium 2012

Community associated Staphylococcus aureus (strain MSSA476) is a gram positive cocci capable of infecting many different parts of the body and known to cause serious infections that can be fatal, such as bacterial arthritis and acute endocarditis. To find effective ways of fighting against CA-MRSA strains we must learn more about their ability to infect. The focus of this study was cloning and characterization of a protein referred to as SAS0754. The size of SAS0754 is 340 amino acids and the gene sequence is 1023 nucleotides. The hypothetical function of this protein is that it is an extracellular matrix binding …

A Convenient Synthesis Of 2,6-Dichlorohomonicotinic Acid, Chase Buchanan, Richard W. Fitch

Symposium 2012

In our synthetic efforts toward the alkaloid phantasmidine, we required a convenient source of the title compound. Herein, we describe a short synthesis of 2,6-dichlorohomonicotinic acid by direct allylation of 2,6-dichloropyridine with LDA/allyl chloride, followed by permanganate oxidation of the side chain [figure1]. Yields for the allylation are high, while permanganate oxidation required more adjustment. Successful conditions require the modest acidification of the mixture with acetic acid and cleanup by acid base workup. No chromatography is needed.

Convenient Parallel Synthesis Of Alkyl- And Aryl-S-Tert-Butyl Thiothers, Rebecca Norcross, Jessica Stanfield, Richard W. Fitch

Symposium 2012

While preparing novel cysteine derivatives as oxidation catalysts, we needed S-tert-butylcysteine. We also examined acid-promoted tert-butylation of thiols using tert-butanol as reagent and solvent. While cysteine and aminoethanethiol work well using tBuOH in 4M HCl, other thiols fail in the aqueous environment and aerobic conditions. We examined a variety of aliphatic and aromatic thiols in tBuOH with H2SO4 catalysis and found that argon sparging and the use of 1 eq of acid led to good yields in a parallel format.

The Impact Of Driving Conditions On Phev Battery Performance, Nathan Christensen, John Patten, Steven Srivastava, Gary P. Nola

Green Manufacturing Research Journal

The battery performance of a modified Prius with a 5 kWh plug-in battery was documented for a year to determine the impact of environmental conditions and user attributes on vehicle performance.  Both fuel economy and pure electrical efficiency were compared to ambient temperature.  The fuel economy has a positive relationship with ambient temperature until approximately 70˚F where the efficiency begins to drop.  Electrical performance has a positive linear relationship with ambient temperature.  With the emergence of electric vehicles (EVs) and PHEVs from a variety of automotive manufacturers, information on EV and PHEV performance for consumers will become more important.

Optical Cell For Combinatorial In Situ Raman Spectroscopic Measurements Of Hydrogen Storage Materials At High Pressures And Temperatures, Jason R. Hattrick-Simpers, Wilbur S. Hurst, Sesha S. Srinivasan, James E. Maslar

Faculty Publications

An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storagematerials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element …

An Infrared Imaging Method For High-Throughput Combinatorial Investigation Of Hydrogenation-Dehydrogenation And New Phase Formation Of Thin Films, H. Oguchi, Jason R. Hattrick-Simpers, I. Takeuchi, E. J. Heilweil, L. A. Bendersky

Faculty Publications

We have developed an infrared imaging setup enabling in situ infrared images to be acquired, and expanded on capabilities of an infrared imaging as a high-throughput screening technique, determination of a critical thickness of a Pd capping layer which significantly blocks infrared emission from below, enhancement of sensitivity to hydrogenation and dehydrogenation by normalizing raw infrared intensity of a Mg thin film to an inert reference, rapid and systematic screening of hydrogenation and dehydrogenation properties of a Mg–Ni composition spread covered by a thickness gradient Pd capping layer, and detection of formation of a Mg₂Si phase in a …

The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason R. Hattrick-Simpers, D. Banerjee, Y. Liu, Z. L. Wang, J. P. Liu, S. E. Lofland, D. Josell, I. Takeuchi

Faculty Publications

The effect of the crystallinity and the grain texturing of CoPt hard layers on exchange coupled Fe/CoPt soft/hard magnetic systems was studied using gradient thickness multilayer thin films. We have studied the hard layer structures by transmission electron microscopy and x-ray diffraction, and characterized the exchange coupling interaction through magnetization loops obtained by the magneto-optical Kerr effect measurement. We found that exchange coupling strongly depends on the crystalline characteristics of the CoPt hard layer. There is correlation between the mixture of different grain orientations of the CoPt hard layer and coupling efficiency. In particular, interlayer coupling is enhanced when there …

Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya

Faculty Publications

A high-throughput high-sensitivity optical technique for measuringmagnetostriction of thin-film composition-spread samples has been developed. It determines the magnetostriction by measuring the induced deflection of micromachined cantilever unimorph samples. Magnetostrictionmeasurements have been performed on as-deposited Fe–Ga and Fe–Ga–Al thin-film composition spreads. The thin-film Fe–Ga spreads display a similar compositional variation of magnetostriction as bulk. A previously undiscovered peak in magnetostriction at low Ga content was also observed and attributed to a maximum in the magnetocrystalline anisotropy. Magnetostrictive mapping of the Fe–Ga–Al ternary system reveals the possibility of substituting up to 8at.%Al in Fe₇₀Ga₃₀ without significant degradation of magnetostriction.

Demonstration Of Magnetoelectric Scanning Probe Microscopy, Jason R. Hattrick-Simpers, Liyang Dai, Manfred Wuttig, Ichiro Takeuchi, Eckhard Quandt

Faculty Publications

A near-field room temperature scanning magnetic probe microscope has been developed using a laminated magnetoelectric sensor. The simple trilayer longitudinal-transverse mode sensor, fabricated using Metglas as the magnetostrictive layer and polyvinylidene fluoride as the piezoelectric layer, shows an ac field sensitivity of 467±3μV∕O_e in the measured frequency range of 200Hz–8kHz. The microscope was used to image a 2mm diameter ring carrying an ac current as low as 10⁻⁵A. ac fields as small as 3×10⁻¹⁰T have been detected.

Rapid Structural Mapping Of Ternary Metallic Alloy Systems Using The Combinatorial Approach And Cluster Analysis, C. J. Long, Jason R. Hattrick-Simpers, M. Murakami, R. C. Srivastava, I. Takeuchi, V. L. Karen, X. Li

Faculty Publications

We are developing a procedure for the quick identification of structural phases in thin film composition spread experiments which map large fractions of compositional phase diagrams of ternary metallic alloy systems. An in-house scanning x-ray microdiffractometer is used to obtain x-ray spectra from 273 different compositions on a single composition spread library. A cluster analysissoftware is then used to sort the spectra into groups in order to rapidly discover the distribution of phases on the ternary diagram. The most representative pattern of each group is then compared to a database of known structures to identify known phases. Using this method, …

Data Management And Visualization Of X-Ray Diffraction Spectra From Thin Film Ternary Composition Spreads, I. Takeuchi, C. J. Long, O. O. Famodu, M. Murakami, Jason R. Hattrick-Simpers, G. W. Rubloff, M. Stukowski, K. Rajan

Faculty Publications

We discuss techniques for managing and visualizing x-ray diffraction spectrum data for thin film composition spreads which map large fractions of ternary compositional phase diagrams. An in-house x-ray microdiffractometer is used to obtain spectra from over 500 different compositions on an individual spread. The MATLAB software is used to quickly organize the data and create various plots from which one can quickly grasp different information regarding structural and phase changes across the composition spreads. Such exercises are valuable in rapidly assessing the “overall” picture of the structural evolution across phase diagrams before focusing in on specific composition regions for detailed …

Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason R. Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. L. Wang, J. P. Liu, S. E. Lofland, Somdev Tyagi, J. W. Freeland, D. Giubertoni, M. Bersani, M. Anderle

Faculty Publications

We have fabricated Fe∕Sm–Co bilayers with gradient Fe thicknesses in order to systematically study the dependence of exchange coupling on the thickness of the Fe layer. The Fe layer was deposited at two different temperatures (150 and 300°C) to study the effect of deposition temperature on the exchange coupling. Magneto-optical Kerr effect and x-ray magnetic circular dichroism (XMCD) have been employed as nondestructive rapid characterization tools to map the magnetic properties of the gradient samples. Systematic enhancement in exchange coupling between the soft layer and the hard layer is observed as the soft layer thickness is decreased. Separate exchange couplings …

Fuel Cells, Frederick J. Munster Jr.

Maine Collection

Fuel Cells

by Frederick J. Munster Jr.

Edited by: Mr. Christopher Carroll

Maine Department of Economic Development, Augusta, Maine, 1998.

Contents: Hydrogen / Hydrogen Safety / Electrolysis / Electrolyzers / History of Fuel Cells / How Fuel Cells Operate / Fuel Cell Types / Fuel Cell Electrochemistry / Power Systems / Fuel Cells in Transportation / Hydrogen Powered Internal Combustion Engines / Home, Garden, Education and Industry / For More Information / Glossary / References

Galvanostatic Pulse And Pulse Reverse Plating Of Zinc-Nickel Alloys From Sulfate Electrolytes On A Rotating Disc Electrode, Branko N Popov, M. Ramasubramanian, S. N. Popova, Ralph E. White, K-M. Yin

Faculty Publications

Galvanostatic pulse and pulse reverse techniques have been used to study the plating of zinc–nickel alloys in the presence of nonyl phenyl polyethylene oxide. The effects of average current density, rotation speed of disc electrode and the presence of nonyl phenyl polyethylene oxide in the electrolyte on deposition of zinc–nickel alloys were evaluated. Zinc–nickel plating bath solution chemistry was studied by determining the equilibrium concentrations at various pH levels. It was found that the alloy composition was determined by solution equilibria, mass transfer of the electroactive species within the diffusion layer and by the surface coverage of nonyl phenyl polyethylene …