Chemistry Commons^™

Testing The Underlying Chemical Principles Of The Biotic Ligand Model (Blm) To Marine Copper Systems: Measuring Copper Speciation Using Fluorescence Quenching, Tara N. Tait, James C. Mcgeer, Scott Smith

Chemistry Faculty Publications

Speciation of copper in marine systems strongly influences the ability of copper to cause toxicity. Natural organic matter (NOM) contains many binding sites which provides a protective effect on copper toxicity. The purpose of this study was to characterize copper binding with NOM using fluorescence quenching techniques. Fluorescence quenching of NOM with copper was performed on nine sea water samples. The resulting stability con- stants and binding capacities were consistent with literature values of marine NOM, show- ing strong binding with log K values from 7.64 to 10.2 and binding capacities ranging from 15 to 3110 nmole mg C ^{−1 …}

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of …

Multivariate Statistical Analyses Of Air Pollutants And Meteorology In Chicago During Summers 2010–2012, Katrina Binaku, Martina Schmeling

Chemistry: Faculty Publications and Other Works

Aerosol, trace gas, and meteorological data were collected in Chicago, Illinois during 2010–2012 summer air studies. Ozone, nitrogen oxides, acetate, formate, chloride, nitrate, sulfate, and oxalate concentrations as well as temperature, wind speed, wind direction, and humidity data were explored by both principal component analysis (PCA) and canonical correlation analysis (CCA). Multivariate statistical techniques were applied to uncover existing relationships between meteorology and air pollutant concentrations and also reduce data dimensions.

In PCA, principal components (PC) revealed a relationship of ozone and nitrate concentrations with respect to temperature and humidity, coupled with transport of species from the south in relation …

Development Of High-Performing Polydimethylsiloxane-Based Membranes For Carbon Dioxide Separation, Tao Hong

Doctoral Dissertations

Membrane separation is highlighted as one of the most promising approaches to mitigate the excessive CO₂ [carbon dioxide] emission, due to its significant reduction of energy cost compared with many conventional separation techniques. Unfortunately, the separation performance of current membranes does not meet the practical CO₂/N₂ [nitrogen] separation requirements. And due to the huge volume of industrial flue gas, membranes with exceptionally high permeability are needed for practical reasons.

Currently, the separation mechanism of most polymeric membranes is based on size-sieving. However, this method is not sufficient for CO₂/N₂ separations due to the …

Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner

Electronic Theses and Dissertations

Vernal pools are small seasonal wetlands that are a common landscape feature that contribute to biodiversity in northeastern North American forests. However, even basic information about their biogeochemical functions, such as carbon cycling, is limited. Dissolved gas concentrations (CH₄, CO₂) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH₄ and CO₂ at all sampling dates and locations. Concentrations of dissolved CH₄ and CO₂ ranged …

No Evidence For Trace Metal Limitation On Anaerobic Carbon Mineralization In Three Peatland Soils, Jason K. Keller, Jillian Wade

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatlands store roughly one-third of the terrestrial soil carbon and release the potent greenhouse gas methane (CH₄) to the atmosphere, making these wetlands among the most important ecosystems in the global carbon cycle. Despite their importance, the controls of anaerobic decomposition of organic matter to carbon dioxide (CO₂) and CH₄ within peatlands are not well understood. It is known, however, that the enzymes responsible for CH₄ production require cobalt, iron and nickel, and there is a growing appreciation for the potential role of trace metal limitation in anaerobic decomposition. To explore the possibility of …

Wake Up Barren Soil! Improving Enzymatic Function Of Contaminated Soils, Nina M. Goodey

Sustainability Seminar Series

A legacy of industrial use in metropolitan areas has left many soils contaminated with heavy metals and organic compounds. In some impacted soils, contaminants have altered the soils’ properties and ability to function. Soil microorganisms exude enzymes that break down nutrients, helping to nourish microorganisms and plants. Productive soils are often characterized by high enzymatic activities that are needed to convert decaying matter to plant nutrients. In soils where enzymatic function is low or nonexistent, plants may lack nutrients and fail to thrive. This case-study focuses on such a site within Liberty State Park in Jersey City, NJ, a brownfield …

Simplifying Sample Preparation Using Fabric Phase Sorptive Extraction: Analysis Of Trace Targeted Pollutant Residues In Environmental, Biological And Food Samples, Rodolfo Mesa

FIU Electronic Theses and Dissertations

Sample preparation is an essential component of analytical methods in chemistry. It is not only necessary but also presents an opportunity to increase the effectiveness of the method significantly. There are various commercially available technologies for sample preparation, including numerous variations of LLE, SPE, and SPME. However, these technologies all present significant deficiencies, including the inability to extract directly from complex samples such as whole milk. Instrumental analysis has been improved greatly in the last two decades but still is not applicable to complex samples without sample preparation.

This work presents the theory of FPSE, including the synthesis of sol-gel …

Unmanned Aerial Systems For Monitoring Trace Tropospheric Gases, Travis J. Schuyler, Marcelo I. Guzman

Chemistry Faculty Publications

The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes(UASs) can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces the …

The Clean Air Act And Its Impact On Ground Level Ozone Pollution Levels In Los Angeles, California, Rebecca G. Ford

Honors Theses

Ozone (O₃) occurs naturally as a protective, ultraviolet radiation-shielding “Ozone Layer” in the Stratosphere and as a photochemically produced pollutant in the Troposphere. The Clean Air Act (CAA) of 1970 regulates the emission and concentration of O₃ and five other atmospheric pollutants. Since the signing of the CAA, the ongoing question has been whether or not the National Ambient Air Quality Standards (NAAQS) and regulatory policies have had an effect on decreasing O₃ concentration. The Los Angeles metropolitan area is a prime example of how O₃ can be a public health hazard, and taint a …

Development And Non-Toxic And Stable Perovskites For High Efficiency Solar Cells, Duyen H. Cao

Link Foundation Energy Fellowship Reports

The efficiency of halide perovskite solar cells has dramatically increased from 9% to 22% in less than 5 years.1 They have shown promise toward the future for low cost and highly efficient solar electricity. While there are still considerable rooms for device optimization, it is now the time to tackle the device long-term stability and toxicity challenges. The presence of Pb in the champion material, methylammonium lead iodide CH3NH3PbI3, may prevent this technology from large-scale deployment due to environmental and health concerns. Attempts have been made in replacing Pb with other non-toxic metals such as Sn, Bi, or Sb.2-6 Long-term …

Estimation Of Bubble-Mediated Air–Sea Gas Exchange From Concurrent Dms And Co2 Transfer Velocities At Intermediate–High Wind Speeds, Thomas G. Bell, Sebastian Landwehr, Scott D. Miller, Warren J. De Bruyn, Adrian H. Callaghan, Brian Scanlon, Brian Ward, Mingxi Yang, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Simultaneous air–sea fluxes and concentration differences of dimethylsulfide (DMS) and carbon dioxide (CO2/ were measured during a summertime North Atlantic cruise in 2011. This data set reveals significant differences between the gas transfer velocities of these two gases (1kw/ over a range of wind speeds up to 21ms􀀀1. These differences occur at and above the approximate wind speed threshold when waves begin breaking. Whitecap fraction (a proxy for bubbles) was also measured and has a positive relationship with 1kw, consistent with enhanced bubble-mediated transfer of the less soluble CO2 relative to that of the more soluble DMS. However, the correlation …

Observations Of Greenhouse Gas Isotopologues With Ace-Fts And Waccm, Eric Michael Buzan

Chemistry & Biochemistry Theses & Dissertations

Increases in greenhouse gas concentrations in the atmosphere are the major driver of climate change. Quantifying the sources and sinks of these gases is a major focus of research. Measuring isotopologues, or molecules that differ in isotopic composition, is one useful way of constraining the budget of a molecule as they are highly sensitive to different sources and sinks. However, measurements above the surface have been restricted to a few locations and have only reached the lower stratosphere. Satellite-based remote sensing can achieve nearly global measurement coverage, but so far no satellites have measured isotopologues.

Presented here are measurements of …

Linking Organic Matter Dynamics To Management, Restoration, And Climate In The Florida Everglades, Peter Regier

FIU Electronic Theses and Dissertations

The Florida Everglades is a massive and highly managed subtropical wetland ecosystem, strongly influenced by anthropogenic control of freshwater distribution and highly susceptible to a changing climate, including rising sea-level and changes in temperature and rainfall. Shifting hydrologic regimes impact ecosystem function and biogeochemistry, which in turn control the sources, fate, and transport of organic matter. As a master environmental variable, it is essential to understand how organic matter dynamics will respond to changes in the balance between freshwater and saltwater associated with landscape-scale Everglades restoration efforts and climate change. The research comprising this dissertation improves current understanding of the …

Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca

Civil Engineering ETDs

Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …

Evaluation Of A Filtration Sorbent For Remediation Of Arsenic In Groundwater, Clement Do

Electronic Theses, Projects, and Dissertations

A commercially available product, PURA PhosLock, was identified and evaluated for use as a sorbent to remove dissolved arsenic (As) from drinking water. Although marketed as a product to remove phosphate in aquaria, it is composed of iron oxide hydroxide (i.e., FeO(OH)), which is also known to adsorb dissolved As species from water. Arsenic was measured using standard methods and Graphite Furnace Atomic Absorption Spectroscopy. A first rough filtration test was performed to see if the PhosLock adsorbed As well. About 50 g of PhosLock was used to filter 10 L of tap water containing 100 ppb As. No detectable …

Pine Needle Pyrolysis: Bio-Waste Into Biofuel, Alexandra Fuentes

Honors Theses

This project explores the alternate uses of biomass. In particular it focuses on pine needles as a source for biofuels. Pine needles are of interest because in certain Mountain communities they are collected and removed from residential properties. By removing the pine needles, communities create a “defensible space” to prevent wild fires from destroying homes and property. These needles are often placed in regional landfills. The South Tahoe Refuse and Recycling Services alone has more than 4,340 tons of pine needles dumped at their facility annually. This large amount of biomass can be a potential energy source.

The focus of …

Phosphomolybdic Acid Catalysis Of Cellulose Hydrolysis, Troy R. Dolmetsch

Undergraduate Honors Theses

Renewable sources such as cellulose derived biofuels are sought after in order to replace fossil fuel sources that are currently used to meet energy demands. Cellulose is a biological polymer composed of a chain of glucose molecules. Hydrolysis of cellulosic materials then has potential to serve as a source of renewable energy in the form of biofuels. The crystalline structure of cellulose is very stable, and current methods of catalyzed hydrolysis are inefficient for industrial application. This project explores the use of phosphomolybdic acid (PMA) in water to catalyze hydrolysis of microcrystalline cellulose. Temperature of hydrolysis was varied from 40 …

Characterization Of Dust On Solar Devices In Southern Nevada, Jason Sylva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dust can impact the efficiency of solar energy collection devices, and in some arid environments, dust can reduce solar energy efficiency up to 30%. Reducing the impact of dust is therefore critical in the expansion of solar technology throughout regions where solar energy is utilized. Characterization of suspended and settled particulate matter can assist in developing strategies for dust mitigation. With the characterization of suspended and settled particulate in remote, rural, and urban environments, more informed decisions can be made regarding the selection of coating material on solar panels as well as developing cleaning and maintenance procedures. Particulate matter that …

Design Of 3d Macroporous Inverse Opal Tio2 Binary And Ternary Composites Sensitized With Gold Nanoparticles And Cds Quantum Dots For Photocatalysis, Daniel A. Corella

Master of Science in Chemical Sciences Theses

Materials composed of titanium (IV) oxide (TiO₂) have received enormous scientific interest due to titania’s abundance, non-toxicity, and photocatalytic proficiency, however its large band gap limits its applicability under ambient conditions. Various attempts have been made to incorporate titania into composite systems to sensitize it for activity under a broader range of wavelengths. One such method includes utilizing narrow band gap semiconductors to form an electron transfer process analogous to photosynthesis referred to as a Z-scheme. Z-scheme systems can catalyze the decomposition of aqueous pollutants via generation of reactive oxygen species after input of sunlight. This work reports …

Physiological Effects Of Five Different Marine Natural Organic Matters (Noms) And Three Different Metals (Cu, Pb, Zn) On Early Life Stages Of The Blue Mussel (Mytilus Galloprovincialis), Lygia Sega Nogueira, Adalto Bianchini, Scott Smith, Marianna Basso Jorge, Rachael L. Diamond, Chris M. Wood

Chemistry Faculty Publications

Metals are present in aquatic environments as a result of natural and anthropogenic inputs, and may induce toxicity to organisms. One of the main factors that influence this toxicity in fresh water is natural organic matter (NOM) but all NOMs are not the same in this regard. In sea water, possible protection by marine NOMs is not well understood. Thus, our study isolated marine NOMs by solid-phase extraction from five different sites and characterized them by excitation-emission fluorescence analysis—one inshore (terrigenous origin), two offshore (autochthonous origin), and two intermediate in composition (indicative of a mixed origin). The physiological effects of …

The Coastal Monitor: Vol 2. No 1., John Tanacredi Ph.D.

The Coastal Monitor

There is something enchanting and vibrant about viewing the coast. Every day at CERCOM we are welcomed by either a vivid sunrise, a view of the barrier island Fire Island and a blending of the sky across the horizon, ultimately flooding the Great South Bay with either clouds or sunshine that reveals the Bay’s surface as either shimmering with sunlight, or an integration of sky and water as an endless ocean. I don’t normally wax poetic but the varying sights along the near shore ocean and this embayment beckon our scientific inquisitiveness. What’s below the surface water? How do animals …

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

Graduate Student Portfolios, Professional Papers, and Capstone Projects

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 products …

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 this research …

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 …

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) dynamically …

Evaluation Of Earth-Abundant Monometallic And Bimetallic Complexes For Catalytic Water Splitting, Kenneth Kwame Kpogo

Wayne State University Dissertations

The development of affordable water splitting catalysts from Earth-abundant transition metal ions such as Co and Mn is of immense scientific interest. Aiming to develop an efficient water splitting catalyst, a Co(II) complex featuring an asymmetric, pentadentate quinolyl-bispyridine ligand with a phenylenediamine backbone was synthesized and characterized by spectroscopic, spectrometric, and X-ray analysis. The Co ion was selected because of its ability to undergo redox conversions from 3d5 CoIV through 3d8 CoI thereby making it a suitable catalyst that can withstand harsh structural and electronic changes during catalysis. The electrocatalytic water reduction activity of the catalyst at neutral pH gave …

The Applications Of Rate Constants In Commercial Methane Digesters, Alyssa Nuñez

Natural Sciences Student Research Presentations

This slide presentation for the Natural Sciences Poster Session at Parkland College summarizes a study conducted to test the effectiveness of rate constants to measure stability and productivity in commercial methane digesters. The study concluded that using rate constants can improve peak production and make methane order an economically viable energy option. The study also concluded that nickel supplements have a large effect on rate constants.

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

Wojciech Budzianowski

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

Wojciech Budzianowski

No abstract provided.