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Development Of High Performance Gas Separation Membranes Through Intelligent Catalyst And Monomer Design, Kevin Richard Gmernicki 2017 University of Tennessee, Knoxville

Development Of High Performance Gas Separation Membranes Through Intelligent Catalyst And Monomer Design, Kevin Richard Gmernicki

Doctoral Dissertations

Polymer membranes are a valuable tool for separating components of liquid and gas mixtures. Heavily inspired by biological systems, the idea of using the intrinsic properties of polymers to perform otherwise energy-intensive tasks is attractive for applications such as water desalination, natural gas sweetening, and post-combustion carbon capture. Of particular interest to our research group, post-combustion carbon capture is a promising potential solution aimed at reducing the carbon footprint involved with production, transportation, and storage of electrical energy generation.

Every year, the United States produces close to seven billion metric tons of carbon dioxide, of which a significant portion is ...


Channel Bar Morphology, Distribution, And Mining-Related Geochemistry In The Big River, St. Francois County, Missouri: Implications For Geomorphic Recovery, Lindsay Marie Olson 2017 Missouri State University

Channel Bar Morphology, Distribution, And Mining-Related Geochemistry In The Big River, St. Francois County, Missouri: Implications For Geomorphic Recovery, Lindsay Marie Olson

MSU Graduate Theses

Tailings releases associated with large-scale historical Pb mining in St. Francois County, Missouri resulted in system-wide contamination of Pb and excess sediment in the Big River. Previous studies have addressed basin and segment scale variability of the contaminants; however, little is known about reach and bar scale variability. This study addresses how mining sediment inputs influence bar form and geochemistry across a range of scales. Bar sediment samples were collected at 21 reaches and analyzed for particle size and geochemistry, while air photo analysis was used to evaluate channel morphology, bar type, and area. Bar area is initially low in ...


Influence Of Histidine Residues, Ph And Charge Interactions On Membrane-Spanning Peptides, Ashley N. Henderson 2017 University of Arkansas, Fayetteville

Influence Of Histidine Residues, Ph And Charge Interactions On Membrane-Spanning Peptides, Ashley N. Henderson

Theses and Dissertations

Designed transmembrane peptides were employed for investigations of histidine residues within the hydrophobic environment of the lipid bilayer by means of oriented solid-state deuterium NMR spectroscopy. Using the model peptide GWALP23 sequence (GGALW(LA)6LWLAGA) as a host framework, the effects of single and double histidine mutations were explored. Replacement of leucine residue 12 to polar neutral histidine had little influence on the peptide average orientation, however under strongly acidic pH conditions in DOPC bilayers, the histidine becomes positively charged (pKa 2.5) and the GWALP23-H12 peptide exits the membrane and adopts a surface-bound orientation. Conversely, mutation of leucine 14 ...


Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman 2017 University of Kentucky

Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman

Chemistry Faculty Publications

Anthropogenic activities contribute benzene, toluene, and anisole to the environment, which in the atmosphere are converted into the respective phenols, cresols, and methoxyphenols by fast gas-phase reaction with hydroxyl radicals (HO(•)). Further processing of the latter species by HO(•) decreases their vapor pressure as a second hydroxyl group is incorporated to accelerate their oxidative aging at interfaces and in aqueous particles. This work shows how catechol, pyrogallol, 3-methylcatechol, 4-methylcatechol, and 3-methoxycatechol (all proxies for oxygenated aromatics derived from benzene, toluene, and anisole) react at the air-water interface with increasing O3(g) during τc ≈ 1 μs contact time and contrasts their ...


Annual Variation In Event-Scale Precipitation Δ 2 H At Barrow, Ak, Reflects Vapor Source Region, Annie Putman, Xiahong Feng, Leslie Sonder, Eric Posmentier 2017 Dartmouth College

Annual Variation In Event-Scale Precipitation Δ 2 H At Barrow, Ak, Reflects Vapor Source Region, Annie Putman, Xiahong Feng, Leslie Sonder, Eric Posmentier

Open Dartmouth: Faculty Open Access Articles

In this study, precipitation isotopic variations at Barrow, AK, USA, are linked to conditions at the moisture source region, along the transport path, and at the precipita- tion site. Seventy precipitation events between January 2009 and March 2013 were analyzed for δ2H and deuterium ex- cess. For each precipitation event, vapor source regions were identified with the hybrid single-particle Lagrangian inte- grated trajectory (HYSPLIT) air parcel tracking program in back-cast mode. The results show that the vapor source re- gion migrated annually, with the most distal (proximal) and southerly (northerly) vapor source regions occurring during the winter (summer). This may ...


Spectrofluorometric Analysis Of Bisphenol-A In Drinking Water Bottles, Jeff Brochetti 2017 University of Lynchburg

Spectrofluorometric Analysis Of Bisphenol-A In Drinking Water Bottles, Jeff Brochetti

Student Scholar Showcase

Spectrofluorometric Analysis of Bisphenol-A in Drinking Water Bottles

Bisphenol-A (BPA) is of environmental concern due to its ability to act as an endocrine disruptor in humans and many other animals. In the food industry, BPA is widely used in the production of plastic bottles and plastic liners in aluminum cans. Over time, trace amounts of BPA can leach from the container and into the contents inside. A new method of testing for trace amount of BPA involved the formation of an inclusion complex with ß-Cyclodextrin. With the formation of the inclusion complex, it becomes much easier to analyze low concentrations ...


Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali 2017 University of Kentucky

Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali

Chemistry Faculty Publications

How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence ...


Multi-Scaled Approaches For Protecting Montana's Watersheds And Water Resources, Elizabeth Yoder 2017 University of Montana, Missoula

Multi-Scaled Approaches For Protecting Montana's Watersheds And Water Resources, Elizabeth Yoder

Graduate Student Portfolios

The central theme carried among my four portfolio pieces is: using scientific and governmental approaches to conserve watershed health. For the purposes of this portfolio, I define watershed health as a very general term that describes the state of water quantity and quality that is available for human and ecosystem needs in a watershed. I see each of my portfolio pieces focusing on a different scale and method (i.e., science or government, including different levels of government, local, state and federal) for conserving watershed health. My first portfolio piece reviews water quality degradation caused by pharmaceuticals and personal care ...


Detection And Quantitation Of Tetracycline Antibiotics In Agricultural Swine Wastes, Ali Jamal Abdulrheem 2017 wku

Detection And Quantitation Of Tetracycline Antibiotics In Agricultural Swine Wastes, Ali Jamal Abdulrheem

Masters Theses & Specialist Projects

The spread of tetracyclines through agricultural systems is causing the present bacteria to develop antibiotic resistance. The spread of this bacteria, as well as the tetracycline antibiotics in the environment is dangerous because these antibiotics pose health hazards for humans. The overuse of antibiotics, which are added to livestock feed, results in the antibiotics being released into the environment via animal feces. In this research, we have attempted to design an analytical method to isolate antibiotics from agricultural wastes with subsequent detection using liquid chromatography and mass spectrometry (LC-MS). The antibiotics investigated in this study were tetracycline, chlortetracycline, and oxytetracycline ...


Polychlorinated Biphenyls, Polybrominated Biphenyls, Polychlorinated Dibenzo-P-Dioxins And Polychlorinated Dibenzofurans, Prasada Rao S. Kodavanti, Joseph Valdez, Jae-Ho Yang, Margarita Curras Collazo, Bommanna G. Loganathan 2017 United States Environmental Protection Agency, Research Triangle Park, NC.

Polychlorinated Biphenyls, Polybrominated Biphenyls, Polychlorinated Dibenzo-P-Dioxins And Polychlorinated Dibenzofurans, Prasada Rao S. Kodavanti, Joseph Valdez, Jae-Ho Yang, Margarita Curras Collazo, Bommanna G. Loganathan

Faculty & Staff Research and Creative Activity

Environmental contamination levels, human exposure, toxicokinetics, and health effects of PCBs, PBBs, PCDDs/PCDFs are discussed.


Reactivity Of Ketyl And Acetyl Radicals From Direct Solar Actinic Photolysis Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman 2017 University of Kentucky

Reactivity Of Ketyl And Acetyl Radicals From Direct Solar Actinic Photolysis Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The variable composition of secondary organic aerosols (SOA) contributes to the large uncertainty for predicting radiative forcing. A better understanding of the reaction mechanisms leading to aerosol formation such as for the photochemical reaction of aqueous pyruvic acid (PA) at λ ≥ 305 nm can contribute to constrain these uncertainties. Herein, the photochemistry of aqueous PA (5-300 mM) continuously sparged with air is re-examined in the laboratory under comparable irradiance at 38° N at noon on a summer day. Several analytical methods are employed to monitor the time series of the reaction, including (1) the derivatization of carbonyl (C═O) functional ...


Topological And Thermodynamic Factors That Influence The Evolution Of Small Networks Of Catalytic Rna Species, Jessica Anne Mellor Yeates, Philippe Nghe, Niles Lehman 2017 Portland State University

Topological And Thermodynamic Factors That Influence The Evolution Of Small Networks Of Catalytic Rna Species, Jessica Anne Mellor Yeates, Philippe Nghe, Niles Lehman

Chemistry Faculty Publications and Presentations

An RNA-directed recombination reaction can result in a network of interacting RNA species. It is now becoming increasingly apparent that such networks could have been an important feature of the RNA world during the nascent evolution of life on the Earth. However, the means by which such small RNA networks assimilate other available genotypes in the environment to grow and evolve into the more complex networks that are thought to have existed in the prebiotic milieu are not known. Here, we used the ability of fragments of the Azoarcus group I intron ribozyme to covalently self-assemble via genotype-selfish and genotype-cooperative ...


Determination Of Optical Properties Of Secondary Organic Aerosols Using Uv-Vis Spectroscopy, Vanessa Selimovic, Matthew E. Wise, John Shilling 2017 Concordia University - Portland

Determination Of Optical Properties Of Secondary Organic Aerosols Using Uv-Vis Spectroscopy, Vanessa Selimovic, Matthew E. Wise, John Shilling

Matthew E. Wise

  • Aerosols interact differently with the atmosphere depending on:
    • Composition
    • Size
    • Phase
    • Reactivity
    • Optical Properties
  • Reactivity with atmosphere determines impact on Earth’s radiative budget

[excerpt]


Digital Fabrication Of An Atmospheric Aerosol Impactor, Stefan J. Vincent, Shawn Daley, Matthew E. Wise 2017 Concordia University - Portland

Digital Fabrication Of An Atmospheric Aerosol Impactor, Stefan J. Vincent, Shawn Daley, Matthew E. Wise

Matthew E. Wise

Atmospheric aerosol (AA) particles are defined as solid or liquid particles suspended in the air. AA particles smaller than 10 μm (1x10-5 meters) in diameter are small enough to bypass the upper respiratory system which functions as a filter for harmful substances entering the lungs. AA particles can be collected using a device called an aerosol impactor. After collection, the particles can be analyzed offline for chemical composition using a variety of analytical techniques. The weight of a commercially manufactured AA particle impactor poses an issue if it is attached to a mobile AA particle sampling platform such as ...


Capture And Densification Of Floating Hydrophobic Liquids By Natural Granular Materials, Daria Boglaienko 2017 Florida International University

Capture And Densification Of Floating Hydrophobic Liquids By Natural Granular Materials, Daria Boglaienko

FIU Electronic Theses and Dissertations

Densification and submergence of floating crude oil is proposed as a novel oil spills treatment method. Surface application of dry granular materials (e.g., quartz sand, limestone) on top of a floating oil layer increases the density of the floating oil phase/granule mixture and leads to formation of relatively large and stable aggregates with significant amounts of captured oil. The aggregates separate from the floating hydrophobic phase and settle by gravity. Implementation of this method will reduce the impact radius of a spill and its mobility, preventing direct contamination of beaches, coastal flora and fauna.

The major objective of ...


Nitrate Radicals And Biogenic Volatile Organic Compounds: Oxidation, Mechanisms And Organic Aerosol, Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Hermann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert McLaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, Rahul A. Zaveri 2017 Georgia Institute of Technology

Nitrate Radicals And Biogenic Volatile Organic Compounds: Oxidation, Mechanisms And Organic Aerosol, Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Hermann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert Mclaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, Rahul A. Zaveri

Chemistry Faculty Publications

Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of ...


A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy VanLoocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu 2017 Arizona State University

A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu

Andy VanLoocke

Utility of perennial bioenergy crops (e.g., switchgrass and miscanthus) offers unique opportunities to transition toward a more sustainable energy pathway due to their reduced carbon footprint, averted competition with food crops, and ability to grow on abandoned and degraded farmlands. Studies that have examined biogeophysical impacts of these crops noted a positive feedback between near-surface cooling and enhanced evapotranspiration (ET), but also potential unintended consequences of soil moisture and groundwater depletion. To better understand hydrometeorological effects of perennial bioenergy crop expansion, this study conducted high-resolution (2-km grid spacing) simulations with a state-of-the-art atmospheric model (Weather Research and Forecasting system ...


C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski

Wojciech Budzianowski

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Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski 2017 Wroclaw University of Technology

Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Digital Fabrication Of An Atmospheric Aerosol Impactor, Stefan J. Vincent, Shawn Daley, Matthew E. Wise 2017 Concordia University - Portland

Digital Fabrication Of An Atmospheric Aerosol Impactor, Stefan J. Vincent, Shawn Daley, Matthew E. Wise

Math & Science Department (SURI)

Atmospheric aerosol (AA) particles are defined as solid or liquid particles suspended in the air. AA particles smaller than 10 μm (1x10-5 meters) in diameter are small enough to bypass the upper respiratory system which functions as a filter for harmful substances entering the lungs. AA particles can be collected using a device called an aerosol impactor. After collection, the particles can be analyzed offline for chemical composition using a variety of analytical techniques. The weight of a commercially manufactured AA particle impactor poses an issue if it is attached to a mobile AA particle sampling platform such as ...


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