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Chemistry

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Full-Text Articles in Physical Sciences and Mathematics

Impact Of Ocean Acidification On Aphotic Biogeochemical Production Of Reactive Oxygen Species, Sarah Ann Murphy May 2015

Impact Of Ocean Acidification On Aphotic Biogeochemical Production Of Reactive Oxygen Species, Sarah Ann Murphy

Theses and Dissertations

Reactive oxygen species (ROS) are critical to global maintenance of the global organic carbon cycle, sulfur cycle, oxygen cycle, and transition metal cycles. The primary source of ROS is commonly considered to be photolysis or photochemically driven reactions, however ROS also exist in aphotic zones. A geochemical mechanism for the same in dark environments based on the tidally driven, episodic movement of anoxic groundwaters through oxidized, Fe(III) rich sediments is shown. Predictive models were developed based on in vitro experiments and tested using sediment samples collected from a saline tidal creek in the estuary at Murrell’s Inlet, South Carolina. These …


Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles May 2015

Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles

University Scholar Projects

Central to the advancement of small molecule synthesis is the ability to develop methodologies that reimagine well known chemistry in a new, environmentally friendly manner. In this thesis two central themes emerge: oxoammonium salt oxidations and trifluoromethyl incorporation using fluoroform gas. Several projects have been developed surrounding oxoammonium salt chemistry, which are featured by their mild conditions, ease of use, and the metal-free, recyclable nature of the oxidant. Trifluoromethylation using fluoroform gas finds its utility in the use of a potent greenhouse gas waste product as a benchtop reagent.


Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles May 2015

Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles

Honors Scholar Theses

Central to the advancement of small molecule synthesis is the ability to develop methodologies that reimagine well known chemistry in a new, environmentally friendly manner. In this thesis two central themes emerge: oxoammonium salt oxidations and trifluoromethyl incorporation using fluoroform gas. Several projects have been developed surrounding oxoammonium salt chemistry, which are featured by their mild conditions, ease of use, and the metal-free, recyclable nature of the oxidant. Trifluoromethylation using fluoroform gas finds its utility in the use of a potent greenhouse gas waste product as a benchtop reagent.


Chemistry And Biochemistry News, Georgia Southern University Apr 2015

Chemistry And Biochemistry News, Georgia Southern University

Department of Chemistry and Biochemistry News (2015-2023)

  • Chemistry Students Make a Splash at GSU Research Symposium


Learning Chemistry Through Experimentation, Brent Kamba `, Dr. Jennifer Nielson Apr 2015

Learning Chemistry Through Experimentation, Brent Kamba `, Dr. Jennifer Nielson

Journal of Undergraduate Research

There is a great need for students to learn scientific skills in Uganda. Very few students pass the national chemistry exams (about 40%) and even fewer go on to study science fields in higher education. The teaching methods in Uganda are a little bit old fashion where students often just learn facts and practise rote memorization. Rarely do they develop the critical and analytical skills to help them succeed in science jobs. Teachers also express that the curriculum is very theoretical, and not experimental.


Microbial Communities Of The Providence River, Jacqueline Kratch Apr 2015

Microbial Communities Of The Providence River, Jacqueline Kratch

Honors Projects in Science and Technology

The Providence River has been industrialized for over one-hundred years. Industries such as oil storage and metal recycling facilities have left high levels of pollutant metals, including lead (Pb), in the soil and water. The elevated Pb concentrations in these environments influence the selection of Pb resistance mechanisms in the bacterial community1. One mechanism of heavy metal resistance is the Pb efflux pump, consisting of proteins in the cell membrane that aid in the transport of Pb out of the cell2. In this study we investigated the co-occurrence of Pb efflux pumps and antibiotic efflux pumps in bacteria from Pb …


Chemistry And Biochemistry News, Georgia Southern University Apr 2015

Chemistry And Biochemistry News, Georgia Southern University

Department of Chemistry and Biochemistry News (2015-2023)

  • Eagles Fly to Denver for Chemistry Presentations


Assessment Of Silk Degradation Using Pyrolysis, Conor Makepeace Apr 2015

Assessment Of Silk Degradation Using Pyrolysis, Conor Makepeace

Honors Projects in Science and Technology

The purpose of this research is to investigate the molecular constitution of silk and the specific causes of post-production degradation in silk material. This capstone project focused specifically on the conditions and degradation of ancient Chinese silk products provided by the Chinese National Silk Museum. Modern silk products were artificially degraded and compared to the ancient silk using Py-GC-MS and comparative analytic techniques. This investigation revealed that the ancient silk products most likely underwent degradation in elevated temperatures while in the presence of moisture and the absence of sunlight or UV radiation during long term burial.


A Comparison Of Student Perceptions To Actual Performance In Chemistry, Ross Hudson Mar 2015

A Comparison Of Student Perceptions To Actual Performance In Chemistry, Ross Hudson

Dr Ross Hudson

This research was part of a larger study into student performance in senior chemistry with regard to question type and content. This paper examines student perceptions about question type and context and compares these perceptions to actual performance. How students perceive different types of questions and how it influences their self-belief and motivation were the focus of this study. Student responses to different styles or types of questions have been well researched over time. In this study Year 11 chemistry students were quizzed about their preferences to Multiple-Choice questions and Open Response question types and how the presence of each …


Binding-Induced, Turn-On Fluorescence Of The Egfr/Erbb Kinase Inhibitor, Lapatinib, James N. Wilson Mar 2015

Binding-Induced, Turn-On Fluorescence Of The Egfr/Erbb Kinase Inhibitor, Lapatinib, James N. Wilson

James N Wilson

We report the photophysical properties, binding-induced turn-on emission, and fluorescence imaging of the cellular uptake and distribution of lapatinib, an EGFR/ERBB inhibitor. Lapatinib, a type II, i.e. inactive state, inhibitor that targets the ATP binding pocket of the EGFR family of receptor tyrosine kinases. DFT calculations predict that the 6-furanylquinazoline core of lapatinib should exhibit an excited state with charge transfer character and an S0 to S1 transition energy of 3.4 eV. Absorption confirms an optical tran- sition in the near UV to violet, while fluorescence spectroscopy shows that photoemission is highly sensi- tive to solvent polarity. The hydrophobicity of …


Long-Term Midlatitude Mesopause Region Temperature Trend Deduced From Quarter Century (1990-2014) Na Lidar Observations, Chiao Y. She, D. A. Krueger, Tao Yuan Mar 2015

Long-Term Midlatitude Mesopause Region Temperature Trend Deduced From Quarter Century (1990-2014) Na Lidar Observations, Chiao Y. She, D. A. Krueger, Tao Yuan

All Physics Faculty Publications

The long-term midlatitude temperature trend between 85 and 105 km is deduced from 25 years (March 1990-December 2014) of Na Lidar observations. With a strong warming episode in the 1990s, the time series was least-square fitted to an 11-parameter nonlinear function. This yields a cooling trend starting from an insignificant value of 0.64 ± 0.99 K decade-1 at 85 km, increasing to a maximum of 2.8 ± 0.58K decade-1 between 91 and 93 km, and then decreasing to a warming trend above 103 km. The geographic altitude dependence of the trend is in general agreement with model predictions. …


The Creation And Evaluation Of Novel Canine Training Aids For Cocaine Using Molecularly Encapsulated Sol-Gel Polymers And An Investigation Of Canine Field Accuracy, Michelle Cerreta Mar 2015

The Creation And Evaluation Of Novel Canine Training Aids For Cocaine Using Molecularly Encapsulated Sol-Gel Polymers And An Investigation Of Canine Field Accuracy, Michelle Cerreta

FIU Electronic Theses and Dissertations

Biological detectors, such as canines, are valuable tools used for the rapid identification of illicit materials. However, recent increased scrutiny over the reliability, field accuracy, and the capabilities of each detection canine is currently being evaluated in the legal system. For example, the Supreme Court case, State of Florida v. Harris, discussed the need for continuous monitoring of canine abilities, thresholds, and search capabilities. As a result, the fallibility of canines for detection was brought to light, as well as a need for further research and understanding of canine detection. This study is two-fold, as it looks to not only …


Science Classics, Mark Masthay Feb 2015

Science Classics, Mark Masthay

Mark Masthay

An essay on the impact of the works in the Imprints and Impressions: Milestones in Human Progress, an exhibition of rare books from the collection of Stuart Rose. Exhibition was held Sept. 29-Nov. 9, 2014, at the University of Dayton.


Chemistry Of Hydrogen Oxide Radicals (Hox) In The Arctic Troposphere In Spring, J Mao, D J. Jacob, M J. Evans, J R. Olson, X Ren, W H. Brune, T M. St. Clair, J D. Crounse, K M. Spencer, M R. Beaver, P O. Wennberg, M J. Cubison, J L. Jimenez, A Fried, P Weibring, J G. Walega, S R. Hall, A J. Weinheimer, R C. Cohen, G Chen, J H. Crawford, C Mcnaughton, A D. Clarke, L Jaegle, Jenny A. Fisher, R M. Yantosca, P Le Sager, C C. Carouge Feb 2015

Chemistry Of Hydrogen Oxide Radicals (Hox) In The Arctic Troposphere In Spring, J Mao, D J. Jacob, M J. Evans, J R. Olson, X Ren, W H. Brune, T M. St. Clair, J D. Crounse, K M. Spencer, M R. Beaver, P O. Wennberg, M J. Cubison, J L. Jimenez, A Fried, P Weibring, J G. Walega, S R. Hall, A J. Weinheimer, R C. Cohen, G Chen, J H. Crawford, C Mcnaughton, A D. Clarke, L Jaegle, Jenny A. Fisher, R M. Yantosca, P Le Sager, C C. Carouge

Jenny A Fisher

We use observations from the April 2008 NASA ARCTAS aircraft campaign to the North American Arctic, interpreted with a global 3-D chemical transport model (GEOS-Chem), to better understand the sources and cycling of hydrogen oxide radicals (HOx≡H+OH+peroxy radicals) and their reservoirs (HOy≡HOx+peroxides) in the springtime Arctic atmosphere. We find that a standard gas-phase chemical mechanism overestimates the observed HO2 and H2O2 concentrations. Computation of HOx and HOy gas-phase chemical budgets on the basis of the aircraft observations also indicates a large missing sink for both. We hypothesize that this could reflect HO2 uptake by aerosols, favored by low temperatures and …


The Importance Of Context: An Exploration Of Factors Influencing The Adoption Of Student-Centered Teaching Among Chemistry, Biology, And Physics Faculty, Travis J. Lund, Marilyne Stains Jan 2015

The Importance Of Context: An Exploration Of Factors Influencing The Adoption Of Student-Centered Teaching Among Chemistry, Biology, And Physics Faculty, Travis J. Lund, Marilyne Stains

Chemistry Department: Faculty Publications

Background: Research at the secondary and postsecondary levels has clearly demonstrated the critical role that individual and contextual characteristics play in instructors’ decision to adopt educational innovations. Although recent research has shed light on factors influencing the teaching practices of science, technology, engineering, and mathematics (STEM) faculty, it is still not well understood how unique departmental environments impact faculty adoption of evidence-based instructional practices (EBIPs) within the context of a single institution. In this study, we sought to characterize the communication channels utilized by STEM faculty, as well as the contextual and individual factors that influence the teaching practices …


Restoration Of Headwater And Coastal Fens In The Lake Superior Basin Of Upper Michigan, James A. Bess Jan 2015

Restoration Of Headwater And Coastal Fens In The Lake Superior Basin Of Upper Michigan, James A. Bess

Dissertations, Master's Theses and Master's Reports - Open

In 2009, research projects were initiated at Michigan Technological University to develop restoration techniques for headwater fens and coastal wetlands in the southern Lake Superior Basin in Michigan’s Upper Peninsula. The primary focus of these was to quantify the efficacy of using locally collected seeds as a technique for wetland restoration. Two primary sites were selected, the Sleeper Lake Fen complex in Luce County and the Portage Waterway-Keweenaw Bay region of Lake Superior in Baraga and Houghton Counties. At the Sleeper Lake site, a combination of heavy machinery, seeding and mulch application was used to restore a 1.6 km ditch …


Theoretical Examination Of Solvent And R Group Dependence In Gold Thiolate Nanoparticle Synthesis, Suzanne M. Neidhart, Brian M. Barngrover, Christine M. Aikens Jan 2015

Theoretical Examination Of Solvent And R Group Dependence In Gold Thiolate Nanoparticle Synthesis, Suzanne M. Neidhart, Brian M. Barngrover, Christine M. Aikens

Faculty Publications

The growth of gold thiolate nanoparticles can be affected by the solvent and the R group on the ligand. In this work, the difference between methanol and benzene solvents as well as the effect of alkyl (methyl) and aromatic (phenyl) thiols on the reaction energies and barrier heights is investigated theoretically. Density functional theory (DFT) calculations using the BP86 functional and a triple ζ polarized basis set show that the overall reaction favors methylthiol over phenylthiol with reaction energies of −0.54 and −0.39 eV in methanol, respectively. At the same level of theory, the methanol solvent is favored over the …


07. Criminal Justice, Northeastern State University Jan 2015

07. Criminal Justice, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


04. Botany, Northeastern State University Jan 2015

04. Botany, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


06. Computer Science, Northeastern State University Jan 2015

06. Computer Science, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


03. Biology, Northeastern State University Jan 2015

03. Biology, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


08. Engineering, Northeastern State University Jan 2015

08. Engineering, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


10. Forensic Science, Northeastern State University Jan 2015

10. Forensic Science, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


11. Genetics, Northeastern State University Jan 2015

11. Genetics, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


14. Optometry, Northeastern State University Jan 2015

14. Optometry, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


16. Physics, Northeastern State University Jan 2015

16. Physics, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


17. Psychology, Northeastern State University Jan 2015

17. Psychology, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


13. Mathematics, Northeastern State University Jan 2015

13. Mathematics, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


18. Statistics, Northeastern State University Jan 2015

18. Statistics, Northeastern State University

Oklahoma Research Day Abstracts

No abstract provided.


Characterization Of Cold Drawn Poly L Lactic Acid By Raman Spectroscopy And Raman Hyperspectral Imaging, Ramya Sudha Muttavarapu Jan 2015

Characterization Of Cold Drawn Poly L Lactic Acid By Raman Spectroscopy And Raman Hyperspectral Imaging, Ramya Sudha Muttavarapu

ETD Archive

Artificial modulation of bone growth and repair processes is an important area of current research. Studies have established that the micro mechanical and bulk physical properties of a polymer implant influence its performance behavior and degradation patterns in the body. One important parameter for the class of polymers known as polylactides is the degree of crystalline character. Hence, studying the bulk and micro crystalline composition of an important polymer implant, Poly-L-Lactic acid is the objective of this study. Poly-L-Lactic acid has elastic properties that can be tailored to resemble natural bone and its reaction to mechanical stress. Varying degrees of …