Environmental Chemistry Commons^™

Blue Carbon In Freshwater / Brackish Marshes On The Barrier Islands Of Virginia Aboveground Net Primary Productivity And Carbon Pools, Emily Caitlin Adams

Biological Sciences Theses & Dissertations

"Blue carbon" is a relatively new concept describing carbon distributed tidally and sequestered via net production within coastal ecosystems, including seagrass beds, mangrove forests, and salt-water marshes. These systems sequester carbon at least 10 times faster than terrestrial systems. Fresh to brackish wetlands that receive irregular tidal influence due to overwash and storm events have not been typically studied as blue carbon systems. My objective was to quantify carbon pools within four interdunal fresh to brackish marshes on Hog Island, Virginia to determine their blue carbon potential. Marshes 1 and 2 were farthest from the ocean, below and above a …

Blue Carbon In Coastal Freshwater/Brackish Marshes On The Barrier Islands Of Virginia: Belowground Carbon Dynamics, Nathan M. Sedghi

Biological Sciences Theses & Dissertations

Some coastal ecosystems sequester substantially more carbon (blue carbon) than land locked systems due to high net primary production and deposition associated with oceanic influences. Most blue carbon research has focused on mangroves, seagrass beds, and salt marshes. Studies on blue carbon potential of coastal freshwater marshes are less common. Barrier islands frequently flood, with seawater reaching interior ecosystems. I examined brackish/freshwater marshes on Virginia barrier islands for possible roles as blue carbon systems. I studied four interior marshes on Hog Island, which varied in proximity to a direct overwash path and protection by a trail berm that divides northern …

Polycyclic Aromatic Hydrocarbon Determination In Liver Of Menhaden Exposed To The Deep Water Horizon Oil Spill, Rebecca Hawke

Seton Hall University Dissertations and Theses (ETDs)

The April 2010 BP® oil spill has caused great concern for ecological impacts in the Gulf of Mexico. Crude oil contains polycyclic aromatic hydrocarbon (PAHs) and oil spills increase the exposure of aquatic organisms to this class of chemicals. The overall detrimental health effects associated with PAH exposure depend on the exposure period, the concentration of PAHs, and the toxicity of the PAHs in the mixture. Brevoortia tyrannus and Brevoortia patronus are filter feeding fish commonly known as menhaden and account for over 40% of the commercial industry fisheries catch. As primary consumers, they are a major link in the …

On-Road Heavy-Duty Vehicle Emissions Monitoring System, Gary A. Bishop, Rachel Hottor-Raguindin, Donald H. Stedman, Peter Mcclintock, Ed Theobald, Jeremy D. Johnson, Doh-Won Lee, Josias Zietsman, Chandan Misra

Fuel Efficiency Automobile Test Publications

The introduction of particulate and oxides of nitrogen (NO_x) after-treatment controls on heavy-duty vehicles has spurred the need for fleet emissions data to monitor their reliability and effectiveness. The University of Denver has developed a new method for rapidly measuring heavy-duty vehicles for gaseous and particulate fuel specific emissions. The method was recently used to collect 3,088 measurements at a Port of Los Angeles location and a weigh station on I-5 in northern California. The weigh station NO_x emissions for 2014 models are 73% lower than 2010 models (3.8 vs. 13.9 gNO_x/kg of fuel) and …

Comparing Three Methods For Estimating Ozone Depleting Substance Substitute Greenhouse Gases: Case Study Of The New York City Region, Wallace A. Murray Iii

Theses and Dissertations

This thesis evaluates the United States Environmental Protection Agency (EPA) method for estimating emissions from one source, Ozone Depleting Substances Substitutes (ODS substitutes) by comparing results for the New York City Metropolitan Statistical Area (NYC-MSA) with results from two other methodologies. The EPA’s method utilizes population data and GDP data to estimate and geographically allocate emissions, with little regard for the geographies of industrial activity. The two alternative methods use data for industrial employment and activity to provide results for comparison and perhaps a more accurate accounting and allocation of emissions throughout the NYC-MSA.

Chloroamino Acids As A Chemical Explanation For Viking Labeled Release Soil Activity On Mars, John C. Hironimus

STAR Program Research Presentations

The Viking missions to Mars, which took place in the 1970’s, performed several experiments on martian soil in an attempt to discern if there was microbial life present. In one set of experiments, a nutrient solution containing amino acids and organic substrates tagged with carbon-14 was injected into sample cells containing martian soil, and the evolution of labeled CO2 was monitored. The evolution of labeled CO2 indicated that there was a process occurring that broke down the nutrients in solution and released CO2 as a byproduct. Cellular metabolism releases CO2, so this result supported the idea of microbial life on …

Determination Of Total Peroxide Content In Secondary Organic Aerosol Particles, Matthew E. Wise, John Shilling, Ryan Caylor

CUP Faculty Research

Secondary organic aerosol particles (SOA) formed from the oxidation of monoterpenes can impact the Earth’s radiation balance, act as cloud condensation nuclei and negatively affect human health. In the initial Visiting Faculty Program application, we proposed the use of an ultraviolet-visible spectrometer equipped with a liquid waveguide capillary flow cell to determine the extent to which SOA absorb visible light. The inclusion of Concordia University in the Secondary Organic Aerosol From Forest Emissions Experiment (SOAFFEE) laboratory campaign at PNNL necessitated a change in the proposed experiments. An iodometric-spectrophotometric (IS) technique was developed to quantify the total peroxide content in SOA. …

Determination Of The Optical Properties Of Secondary Organic Aerosol Particles, Matthew E. Wise, John Shilling, Felisha Imholt, Ryan Caylor

CUP Faculty Research

The enhanced greenhouse effect is currently considered to be our most important global environmental problem. While the magnitude of radiation absorbed by greenhouse gases is known to a high certainty, the absorption of radiation by atmospheric aerosol particles is not. In the initial Visiting Faculty Program application, we proposed the use of an ultraviolet-visible (UV/Vis) spectrometer equipped with a liquid waveguide capillary flow cell to determine the extent to which secondary organic aerosol particles (SOA) absorb visible light. Early in the research period, the UV/Vis technique was optimized for three solvent systems (methanol, water and 0.1 M hydrochloric acid). Using …

Pyrolysis-Gc-Ms For The Rapid Environmental Forensic Screening Of Contaminated Brownfield Soil, Azucena Lara-Gonzalo, Michael A. Kruge, I Lores, B Gutiérrez, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

An abandoned chemical plant in Asturias (Spain) was studied using a multi-faceted molecular fingerprinting approach, demonstrating that it is possible to: (1) carefully unravel tangled evidence resulting from multiple pollution sources, and (2) recognize major contaminants largely ignored by conventional analyses. This methodology employed a battery of GC-MS analyses of liquid chromatographic fractions of soil extracts, plus the pyrolysis products of the soil extract's asphaltene fraction and the whole soil itself. In this example, coal tar distillation and the subsequent production of naphthalene, phenols and polymer resins are responsible for most of the soil contamination. Styrene, naphthalene, indene, and their …

Analytical Pyrolysis Principles And Applications To Environmental Science, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Over the past half century, analytical pyrolysis has proven itself to be an effective means for the semiquantitative characterization of complex macromolecular organic substances. It has been demonstrated that instruments such as Py-FID, Py-MS, and in particular, Py-GC/MS can provide valuable geochemical insights when applied to a wide variety of problems in environmental science. The more widespread use of analytical pyrolysis methods in the evaluation of environmental pollution is recommended, because of their relatively low cost and information-rich results.

Pyrolysis is the heating of organic substances in an inert, oxygen-free atmosphere, thereby avoiding combustion. When performed on a large scale, …

Magnetic Mineral Diagenesis In The River‐Dominated Inner Shelf Of The East China Sea, China, Can Ge, Weiguo Zhang, Chenyin Dong, Yan Dong, Jinyan Liu, Nguyen Thi Thu Hien, Huan Feng, Lizhong Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The inner shelf of the East China Sea is a river-dominated margin characterized by fine-grained mud deposits and a rapid sedimentation rate. Three short sediment cores (similar to 2.7m in length) were examined to characterize spatial variations in magnetic mineral diagenesis. The sediment cores were analyzed for sedimentation rates, magnetic properties, particle size distribution, organic carbon, and total sulfur content. The two more proximal cores with higher sedimentation rates (similar to 2.2cm/yr and similar to 0.96cm/yr) do not exhibit obvious effects of reductive dissolution of magnetite with increasing depth, which is consistent with their lower total sulfur content. The offshore …

Comparing Bulk Aerosol Profiles In The Mixed Layer In Coastal Los Angeles And The Inland Empire, Taia Sean Wu

Scripps Senior Theses

Characteristic westerly sea breeze carries air over the Los Angeles Basin in Southern California to the Inland Empire approximately 50 miles inland, directly impacting air quality in both of these two highly polluted regions. As particles play a critical role in air quality and human health, this study compares the bulk aerosol profiles of the Los Angeles pollution "source" and Inland Empire "receptor" regions during the 2013 and 2014 NASA Student Airborne Research Program (SARP) campaigns onboard the NASA DC-8 airborne laboratory. The source and receptor regions were characterized by a series of missed approaches at the Los Angeles International …

Cytotoxic Activity Of Triazole-Containing Alkyl Β-D-Glucopyranosides On A Human T-Cell Leukemia Cell Line, E. Davis Oldham, Larissa M. Nunes, Armando Varela-Ramirez, Stephen E. Rankin, Barbara L. Knutson, Renato J. Aguilera, Hans-Joachim Lehmler

Chemistry and Physics

Simple glycoside surfactants represent a class of chemicals that are produced from renewable raw materials. They are considered to be environmentally safe and, therefore, are increasingly used as pharmaceuticals, detergents, and personal care products. Although they display low to moderate toxicity in cells in culture, the underlying mechanisms of surfactant-mediated cytotoxicity are poorly investigated.

Derivatization And Separation Of Natural Estrogens (Estrone, 17Β-Estradiol, And Estriol) Using Gas Chromatography With Flame Ionization Detection (Gc-Fid), Dena L. Guptill

Masters Theses

A major cause of concern for estrogens found in the environment is that even at very low concentrations (10-100 ng/L) they can have a negative effect on aquatic ecosystems by disrupting endocrine systems. Due to the increasing importance of monitoring the levels of estrogens in the environment, a detection method was developed to identify and quantify three natural estrogens (estrone, 17β-estradiol and estriol) using gas chromatography with flame ionization detection (GC-FID). In addition, the efficacy of two derivatizing agents, N,O-bis(trimethylsilyl) acetamide (BSTA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), was evaluated. The GC detector (FID) was most responsive with E3, followed by E1 and …

Investigation Of Natural Perchlorate Levels In Antarctic Snow In Relation To The Ozone Hole, Thomas Crawford, Alexandria Kub, Han Vid Cho

The Journal of Undergraduate Research

Snow samples collected from the West Antarctic Ice Sheet Divide in January 2013 were analyzed for perchlorate concentrations to determine a possible seasonal variation. These samples were dated for the years 2007 through 2012 using annual variations in sulfate concentration as determined by an ion chromatography (IC) method. Perchlorate concentrations in the samples were measured with an IC instrument paired with tandem mass spectrometry detection. The concentration data show that perchlorate reached an annual maximum concentration in the austral autumn seasons, assuming that snowfall was relatively constant throughout the course of each year. Comparison with published total column ozone density …

On The Catalytic Activity Of Palladium Nanoparticles-Based Anodes Towards Formic Acid Electro-Oxidation: Effect Of Electrodeposition Potential, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof

Chemical Engineering

In this investigation, the catalytic activity of palladium nanoparticles (PdNPs)-modified glassy carbon (GC) (simply noted as PdNPs/GC) electrodes towards the formic acid electro-oxidation (FAO) was investigated. The deposition of PdNPs on the GC substrate was carried out by a potentiostatic technique at different potentials and the corresponding influence on the particles size and crystal structure of PdNPs as well as the catalytic activity towards FAO was studied. Scanning electron microscopy (SEM) demonstrated the deposition of PdNPs in spherical shapes and the average particle size of PdNPs deposited at a potential of 0 V vs. Ag/AgCl/KCl(sat.) was the smallest (ca. 8 …

The Green Chemistry And Filipino Approach To High School Experiments In Saint Paul College Pasig, Ronald G. Santos, Armando M. Guidote Jr

Chemistry Faculty Publications

This paper is a call for teachers to initiate measures in improving the quality of high school chemistry education in the Philippines and that is by going back to practical laboratory work. The experiment presented in this paper is a proof to the possibility of tailor-made experiments that integrate principles of green chemistry. Integrating green chemistry concepts in the design of high school chemistry experiments makes students aware of the responsibility that goes with the use and production of chemicals. Moreover, the experiment was designed to consciously integrate aspects of Filipino culture, values, and traditions. Such enculturation of chemistry by …

Global Ozone Chemistry And Related Trace Gas Data Records For The Stratosphere (Gozcards): Methodology And Sample Results With A Focus On Hcl, H20, And 03, L. Froidevaux, J. Anderson, H. J. Wang, R. A. Fuller, M. J. Schwartz, M. L. Santee, N. J. Livesey, H. C. Pumphrey, P. F. Bernath, J. M. Russell Iii, M. P. Mccormick

Chemistry & Biochemistry Faculty Publications

We describe the publicly available data from the Global OZone Chemistry And Related trace gas Data records for the Stratosphere (GOZCARDS) project and provide some results, with a focus on hydrogen chloride (HCl), water vapor (H₂O), and ozone (O₃). This data set is a global long-term stratospheric Earth system data record, consisting of monthly zonal mean time series starting as early as 1979. The data records are based on high-quality measurements from several NASA satellite instruments and the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) on SCISAT. We examine consistency aspects between the various data sets. …

The Biogeochemistry Of Elemental Sulfur Contaminated Soils: Insights Into Effective Remediation, Michael Ryan Mctee

Graduate Student Theses, Dissertations, & Professional Papers

Soil contamination that results from elemental sulfur (S⁰) deposition is a new occurrence. Elemental sulfur is stockpiled as a byproduct from the oil and gas industry and is deposited by biodegradable trap and skeet targets at shooting ranges. Chemolithotrophs and mixotrophs can oxidize S⁰ to H₂SO₄. Consequently, in areas where excess S⁰ is deposited or stockpiled, soils can acidify to pH values observed with acid mine drainage.

I studied S⁰ contamination at a former sporting clay range. For seven years, the range used biodegradable trap and skeet targets that contained S …

Characterization Of Pm2.5 From Residential Woodstove Use For Source Apportionment Application, Virginia M. Porden

Graduate Student Theses, Dissertations, & Professional Papers

Results are presented for the comparative analysis of the PM_2.5 (Particulate Matter <2.5 µm) emissions from an EPA certified and a Traditional style wood stove using western larch. A total of 92 Quartz QMA 47mm filters were collected using a BGI PM_2.5 SSC (Sharp Cut Cyclone) sampler from each stove type and analyzed on a gas chromatograph-mass spectrometer against blank and deuterated internal standards. The results were analyzed using a Welch’s t-test (α > 0.05) to statistically differentiate between stove designs for temperature, mass, levoglucosan, resin acids (abietic and dehydroabietic), and polycyclic aromatic hydrocarbons [PAH] (acenaphthene, anthracene, benz(a)anthracene, pyrene, and retene). There was no statistical difference in levoglucosan PM_2.5 mass fraction between the stove types, yielding a mean levoglucosan fraction of 9.25% and 95% confidence interval of 8.43% …