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SYNTHESIS OF ADAMANTANE DERIVATIVES INFLUENCED BY THE STUDY OF SHORT ALKANESAdena Issaian, Antoine Stopin, Miguel Garcia-Garibay.
University of California, Los Angeles, Los Angeles, CA.
Molecular gyroscopes are bulky organic molecules designed to induce particular crystalline structures that contain rotating functional units. Their ability to undergo rapid rotation makes them susceptible to changes in transmission Sciences Physical of light, which makes them appealing for technological innovations in the area of electrooptic displays such as liquid crystals. To develop a platform for the design of these molecules, our project focuses on the synthesis of new tetragonal rigid compounds related to molecular gyroscopes, which will improve the understanding of crystallization of bulky molecules. Since tetraphenyladamantane moieties have shown distinct crystalline structures and rigidity, they were selected as the core of the molecules. Ethane and propane analogs based on tetraphenyladamantane, with their symmetry and possible rotational abilities, were selected in this project to be the first target molecules. Initially, bromoadamantane was reacted with t-butylbromide and aluminum chloride in benzene to yield triphenyladamantane with 71% yield, which made it possible to use it as the next precursor in the pathway. Therefore, through a radical reaction, the synthesis of bromotriphenyl adamantane, with 89% yield, was completed as confirmed by NMR. The synthesis of the final compounds based on tetraphenyladamantane moieties is in progress. Once obtained, their fluorescence and rotational and crystalline properties will be studied to improve our understanding of bulky rigid molecules. These results will later help advance the area of engineering of motion in crystals and electrooptic displays, which are essential for more improvements in the field of liquid crystal technology.
A STUDY OF THE PHYSICOCHEMICAL PROPERTIES OF FIVE GADOLINIUM (III) LIGANDS USING QUANTUM
CHEMICAL METHODSAlexander Roitburt, Maria Benavides.
University of Houston-Downtown, Houston, TX.
The aim of our study was to investigate the physicochemical properties of chelated gadolinium (III) complexes commonly used as contrast media in magnetic resonance imaging (MRI) through the use of computational molecular modeling techniques, specifically, Gaussian functions. Contrast media are used in diagnostic radiology to increase the clarity of various abnormal tissues in MRI. Currently, all approved Gadolinium (III)-based contrast agents are formed through nine-coordinate complexes using various ligands, which alter the ion’s imaging properties, as well as ensure its safe passage through the body. Our study focused on determining the properties of five such ligands; DTPA,
249 UNDERGRADUATE POSTER ABSTRACTS
Cy2DTPA, MS-264-L, BOPTA, and B-21326/7. The study of these structures and their properties is necessary in order to better understand and predict their behavior in physiological systems. Our calculations were performed using density functional theory (DFT) with 2 basis sets (3-21G and 6-31G) to obtain the equilibrium geometries, vibrational frequencies, and IR spectra for the ligands. The highest occupied molecular orbital (HOMO) to lowest occupied molecular orbital (LUMO) energy gap values for all compounds are greater than 4 eV suggesting that the ligands are chemically stable. The compounds exhibit dipole moments ranging between 4 to 5 Debye indicating they possess polar character. Our computed vibrational frequencies were found to be in agreement with experimental values, indicating that our proposed models are fair representations of the actual molecular structures.
WHY EVERYONE SHOULD EAT MORE FRUITS AND VEGETABLES: RADICAL SCAVENGING AND METAL
CHELATING ABILITIES OF PHENOLIC COMPOUNDSDavid Pichardo, Cynthia Selassie.
Pomona College, Claremont, CA.
Scientific studies have increasingly demonstrated that diets rich in fruits, nuts, vegetables, spices, and plant-derived beverages such as red wine reduce the risk of many types of chronic diseases such as cancer, cardiovascular, and neurodegenerative diseases. As we continue to learn more about why diets high in these foods lead to reduced risk of chronic disease, the scientific community has developed an increasing interest in the phytochemicals present in these foods. Amongst these phytochemicals are phenolic compounds, which have been shown to demonstrate significant antioxidant activity and disease-preventive effects. Many chronic diseases have been at least partially attributed to damage caused by reactive oxygen species that can cause deleterious changes to complex cellular molecules such as protein and DNA. By serving as antioxidants, phenolic compounds have the ability to “quench” these reactive oxygen radicals. Additionally, these compounds have an ability to chelate metals, allowing them to mask the prooxidant activity of metals such as iron (Fe2+). This study uses two assays to determine the radical scavenging and metal-chelating abilities of a variety of phenolic compounds. The data that was generated is then used to develop a quantitative structure activity relationship (QSAR) model that allows us to gain an understanding of how the structures and physicochemical attributes of these phenolic entities affect their metal-chelating and radical scavenging abilities, and eventual cytotoxicities. These results should help us learn more about the abilities of polyphenolics to combat oxidative stress induced by both internal and external factors.
SYNTHESIS AND CHARACTERIZATION OF NOVEL ZINC COMPLEXES AS MODELS FOR HYDROLASESMayra Pedraza1, Ghezai Musie, Rebecca Joy.
University of Texas at San Antonio, San Antonio, TX.
In an attempt to develop synthetic models of phosphohydrolase enzymes, noble mono and dinuclear metal complexes using a highly versatile ligand, N,N’-Bis[2-carboxybenzomethyl]-N,N’-Bis[carboxymethyl]-1,3-diaminopropan-2-ol, and various metal ions (Zn2+, Cu2+, Ni2+) have been synthesized. The complexes have been fully characterized using spectroscopic and crystallographic techniques. The ligand, H5ccdp, provided a unique synthetic opportunity to either selectively tether an intramolecular H-bonding network or incorporate a second metal ion into its coordination cavity.
In this presentation, the synthesis and characterization of these novel complexes will be discussed. (Partially funded by NIGMS MBRS-RISE GM060655.)
EARTH SCIENCES/OTHER PHYSICAL SCIENCESFRI-176
EXPANDING MINIMUM PROBABILITY FLOW TO SECOND CLOSEST NEIGHBOR: A STUDY OF TRANSITIONMATRICES Trevor Grand Pre1, Joe Thurakal2, Mike DeWeese2.
DePaul University, Chicago, IL, 2University of California, Berkeley, Berkeley, CA.
1 The DeWeese group has developed a powerful algorithm called minimum probability flow learning for fitting probabilistic models to data. This approach uses a transition matrix that is extremely sparse. The current algorithm uses a transition matrix that maps 2 states differing by 1 bit flip. We hope to expand the algorithm to incorporate states
that differ by 2 spin flips. Expanding the code is the precursor step to optimizing the transition matrix and ultimately creating a faster and more efficient way for fitting probabilistic models to data.
SEASONAL AND DIURNAL COMPONENTS OF WIND POWER AT CRYSTAL COVE PARKAndrew Miller, Charles Zender.
The College of New Jersey, Ewing, NJ, 2University of California, Irvine, Irvine, CA.
1 Wind power is an incredible source of energy that can meet some of California’s high energy demand. With the recent closing of its last nuclear plant, California is more dependent on fossil fuels, making our results even more important. Estimates of coastal wind power have shown that wind power potential in Orange County is weak to moderate, but these estimates do not include the contribution of the diurnal sea breeze to this wind power. This is because data collection of wind power measurements has only occurred twice throughout the day, as opposed to our measurements of wind power, speed, and direction, which have been collected every half hour at Crystal Cove by the meteorology station operated by the University of California, Irvine. The contribution of the sea breeze to wind power is likely significant due to the cubic relationship between wind speed and wind power. Specifically, we will analyze and present data from 2008 to present to characterize both the diurnal and seasonal components of wind power at Crystal Cove Park.
ORIGIN OF METHANE AND OTHER HYDROCARBONS IN MAGMATIC SYSTEMSCristian Virrueta, David Hilton.
Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA.
Tectonic systems such as divergent, convergent, and transform plate boundaries provide geochemists a wide array of volcanic and geothermal edifices to probe the Earth’s interior in order to further understand our planet. The study of carbon isotopes within volatile gases, such as methane, can help pinpoint the origin of these gases and provide evidence of any crustal interaction that takes place during passage from the magmatic source to the surface. In order to study the 13C/12C ratio in methane, a network of glass lines under vacuum pressure are needed to separate, combust, and capture the carbon from geothermal samples prior to analysis using mass spectrometry. We aim to investigate and characterize the carbon isotopic composition of methane at different plate boundaries utilizing
NOVEL RARE EARTH NANOPARTICLES FOR THE DETECTION OF HEAVY METALS IN THE ENVIRONMENTBrian Yust1, Wade Jackson Jr.2.
University of Texas at San Antonio, San Antonio, TX, 2Jackson State University, Jackson, MS.
1 With heavy industrialization in developing countries and little environmental regulation, heavy metals are increasingly being found in the water supply. Water used for irrigation is becoming a major issue because contaminates within it can cause major issues for humans and the environment. Specifically, crops that require flood irrigation such as rice are particularly susceptible to absorbing these toxic elements (heavy metals) and entering into the food supply, which could be detrimental to those who consume them. With proper surface functionalization and the use of rare earth nanoparticles, the presence of heavy metal ions can interact with these nanoparticles and be quantified by quenching a fluorescent signal, shift absorption and through aggregation of particles. With the development of new detection techniques to identify toxic metals such as lead, mercury, and arsenic, sensing for these metals can be obtained through a three-step process. This process includes synthesis, characterization, and surface functionalization. In developing a novel detection scheme, we hope to lay the groundwork for a simple field test such as a test strip or coated cuvette to allow the detection of small amounts of these elements rather than having to send samples to a laboratory. Ultimately, these newly discovered technological materials will be used for a field-ready detection method
for detecting these elements, consequently improving the quality of life for human beings that consume large amounts of these crops and the environments in which these crops are produced.
A FOCUSED STUDY OF METHANE LEAKAGE FROM COMPRESSED NATURAL GAS STATIONS IN THE LOS
ANGELES BASINValerie Carranza1, Francesca Hopkins2, Joshua Miu2, James Randerson2.
Los Angeles Valley College, Valley Glen, CA, 2University of California, Irvine, Irvine, CA.
1 In recent years, natural gas has taken on a larger role in the national energy policy discourse. Natural gas is seen as a fuel that can reduce American dependence on foreign energy and reduce greenhouse gas emissions. However, in terms of net benefits and costs, the implications of increased natural gas consumption are not fully understood; for example, better measurements of methane leakages in natural gas infrastructure are needed to accurately assess the impact of increased natural gas usage on local and regional climates. The goal of our research is to provide a focused analysis of potential methane leakages from compressed natural gas (CNG) stations in the Los Angeles Basin. To improve our understanding of methane leakages, we used a mobile laboratory that is outfitted with cavity-ring down spectrometers measuring concentrations of CH4, CO2, and CO. In addition, we take mobile measurements of C2H6 and O3. A handheld methane analyzer was used as a comparison and accuracy tool in measuring CH4. Data analysis will be conducted with the use of ArcGIS and Matlab. We predict that daytime CH4 emissions at CNG stations will be higher relative to nighttime. Additionally, our team speculates higher methane leakages from CNG storage tanks compared to CNG pumps. By finding sources of methane leakages in specified CNG stations and by gaining a better understanding of the spatial and temporal patterns of CH4 emissions, our research can provide valuable information to reduce the climate footprint of the natural gas industry.
ANALYSIS OF LEAF AREA INDEX USING REFLECTANCE DATA ACROSS AN ELEVATION TRANSECT AS A
BASIS FOR ECOLOGICAL MODELSDion Kucera1, Shane Grigsby2.
Humboldt State University, Arcata, CA, 2University of California, Santa Barbara, Santa Barbara, CA.