Bulletin of the American Physical Society
12th Annual Meeting of the Northwest Section of the APS
Volume 55, Number 6
Friday–Saturday, October 1–2, 2010; Walla Walla, Washington
Session D1: Poster Session (4:30-6:00PM) |
Hide Abstracts |
Room: Cordiner Hall Foyer |
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D1.00001: Relativistic Mass Change in the Fields of Gravitation, Non-Holonomity, and Deformation Dmitri Rabounski This study targets solving the scalar geodesic equation (equation of energy) of a mass-bearing particle travelling in the gravitational field, the field of non-holonomity (rotation) of space, and the field of deformation of space, which are the only three external factors present in the equation. The obtained solutions manifest a change in the mass of the particle according to the distance travelled in the corresponding field. The mass defect due to the field of gravitation is known. The effects of the fields of space non-holonomity and space deformation have not been studied before. In contrast to the gravitational mass defect, registered in the gravitational field near the Earth, these two effects are much smaller: they reach the measurable limit 10$^{-10}$ only in space travel within cosmological distances. A complete report of this study has been submitted to The~Abraham Zelmanov Journal. [Preview Abstract] |
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D1.00002: Stellar Mass Functions using OGLE and MOA Gravitational Microlensing Events Diane Feuillet, Kailash Sahu Gravitational microlensing is an astronomical phenomenon that can be extremely useful in finding a variety of information, ranging from determining mass of the lens to detecting extra solar planets and black holes. The OGLE and MOA groups provide a catalogue of more than 5000 microlensing events observed in the direction of the Galactic bulge over the past ten years. The duration of the event can be used to get a statistical estimate of the mass of the lens. This information was used to derive the present-day mass function of the lenses, which include stars and stellar remnants, in the direction of the Galactic bulge. One can then compare this mass function with the accepted initial mass function of the Galaxy. Compared to the initial mass function, we found a slight excess of high mass objects in the Galactic bulge from the microlensing events. [Preview Abstract] |
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D1.00003: Dune Morphology and Substrate Dependence on Titan Graham Vixie, Jason Barnes, Jani Radebaugh We are using Cassini's Visual and Infrared Mapping Spectrometer (VIMS) to study Titan's sand. Specifically, we are constraining the sand's composition, the precise composition of which is still unknown. Water ice has been ruled out, leaving atmospherically-derived hydrocarbons as the best fit. The means of constraint involved spectrally unmixing images of Titan's dunes. We selected our spectral endmembers using high resolution VIMS IR images (noodle maps), specifically from T20. We have 5 spectral endmembers, labeled by color from VIMS IR maps: dark brown, dark blue, Xanadu bright, equatorially bright, and 5- micron bright. We set up a linear model to test on mixed substrate pixels from the northern Fensal sand dunes. Our model assumes some percent dark brown (sand) and some percent one other endmember. The product is a substrate map of Titan's dune fields, which we will compare with RADAR maps of the same area. Our results will determine if substrate type plays a role in dune morphology and location. [Preview Abstract] |
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D1.00004: Sharing new data from Solar Dynamics Observatory Benji Friedman, E.J. Zita, Zoe Frank New data from the Solar Dynamics Observatory (SDO) provides opportunities to share exciting information about the Sun with people outside the field of science. This presents the challenge of how best to communicate important findings to an audience that may not know the astrophysical vernacular to understand what's going on. This summer, I worked on various methods, including Facebook and Lockheed Martin's Picture of the Day website, to inform the public about the Sun, that mysterious star on which we rely. I will describe methods for finding interesting new solar events, making pictures and movies of solar dynamics, and uploading and annotating them for the public. [Preview Abstract] |
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D1.00005: Solar Plasma Flows and Convection in Oblique Magnetic Fields Christina Smith, E.J. Zita, Neal Hurlburt Moving charges in the Sun's plasma create a complex network of magnetic fields. This is at the heart of dynamic solar events, such as active regions, sunspots, and coronal mass ejections. We study magnetoconvection, the motion of magnetized ionized fluids (plasmas), to better understand the Sun. Models of solar magnetoconvection often assume simplified magnetic fields that are either completely vertical or horizontal. Realistic fields, however, are often inclined at oblique angles. We analyze high resolution data from the Solar Optical Telescope on the Hinode spacecraft, and compare velocities with magnetic field inclinations. We then compare results with predictions from a numerical model of nonlinear compressible convection in oblique magnetic fields. [Preview Abstract] |
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D1.00006: Waves and oscillations in the solar atmosphere Christopher Ballou, Mark Cheung, E.J. Zita, Christina Smith The high temperature plasma of the solar corona and chromosphere is permeated by magnetic fields. The field lines are traced by superheated plasma which allows for observations with diverse wavelengths of light. We can observe and analyze waves and oscillations excited in the solar atmosphere, to gain insight into structures and dynamics of solar active regions. Using images from the Atmospheric Imaging Assembly onboard NASA's Solar Dynamics Observatory, we analyze select oscillations in the solar corona and chromosphere. We use computational and analytical techniques to calculate wave properties and to develop deeper understanding of compelling observations. [Preview Abstract] |
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D1.00007: Beyond the Limb: A Narrow Band EUV search for Background Objects with the AIA Sam Schonfeld As the star closest to Earth, the Sun provides us with the opportunity to study up close and test models for X-ray stellar activity. ~Its close proximity (and consequent brightness), however, makes it challenging to observe the Sun and other celestial objects with the same instrument; thus instrumental cross-calibration difficulties have complicated comparison of the Sun with other stars. ~The new Solar Dynamics Observatory (SDO) launched in February 2010 may at last allow for direct comparison of the Sun and other stars. ~The Atmospheric Imaging Assembly (AIA) onboard the SDO, a series of telescopes taking images of the full Sun at high spatial and temporal resolution in seven extreme ultraviolet (EUV) pass bands, can potentially observe background objects passing within the field of view of the telescopes off the limb of the Sun. ~Young stars and other strong X-ray and EUV emitters may be bright enough to observe after careful background subtraction. Using technical specifications of the telescopes and measured X-ray fluxes of various background sources, we determined that with exposure times of the order of minutes, significantly longer than the standard $\sim $3s exposure, we should be able to observe the brightest background sources when they pass in the AIA field of view. ~We also began determining what kinds of instrumental limitations we need to overcome and how best to make observations of these dim~background sources. [Preview Abstract] |
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D1.00008: Deriving Telescope Properties Using Daytime Sky Observations Shannon Hall, David Harrington High-resolution spectropolarimetry in night-time astronomy is a relatively new but powerful remote sensing technique. In order to make accurate spectropolarimetric measurements using large telescopes it is necessary to derive the calibration of the telescope by recovering the Mueller matrix elements. These calibrations are typically difficult to recover and are functions of wavelength and telescope pointing. We demonstrate a novel technique using observations of the bright, highly polarized, and easily accessible daytime sky. With the calibration of the AEOS 3.67m telescope on Haleakala and the new low-resolution spectropolarimeter LoVIS we illustrate the spectropolarimetric accuracy with observations of AB Aurigae. [Preview Abstract] |
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D1.00009: Optical pumping of gaseous rubidium with elliptically polarized light Kristen Norton, Samantha Nhim, Michaela Kleinert In this poster we will demonstrate a method of visualizing quantum mechanical selection rules and optical pumping effects with a laser diode. We obtain Doppler-free absorption spectra of gaseous rubidium at room temperature using pump-probe absorption spectroscopy with elliptically polarized light. We investigate how the relative polarizations and intensities of the pump and probe beams affect the Doppler-free absorption signal. We will also show how to create an economical method to increase frequency stability of an external-cavity laser diode. [Preview Abstract] |
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D1.00010: Investigating Surface-Enhanced Coherent Anti-Stokes Raman Spectroscopy for Biological Imaging Sarah R. Nichols, Brandon R. Bachler, Jennifer P. Ogilvie Due to the intrinsic molecular contrast it provides, biological imaging based on coherent anti-Stokes Raman scattering (CARS) is appealing. However, weak CARS signals from most biological samples have restricted the applications of CARS microscopy to imaging high number density vibrations such as C-H stretching modes from lipids and proteins. Surface-enhanced CARS (SECARS) offers the possibility of significantly enhanced sensitivity: nanostructured metallic surfaces provide localized field enhancements, increasing CARS signal levels by several orders of magnitude. We are currently investigating coherent and incoherent Raman scattering signals on nanostructured gold substrates to assess the potential sensitivity gain available to biological imaging based on SECARS. [Preview Abstract] |
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D1.00011: Customizing a CRDS Trace Gas Analyzer for Dark Matter Experiments Jared Thompson, Kara Keeter Some proposed dark matter detectors require large amounts of noble gases with ultra-low levels of impurities such as H$_{2}$O, O$_{2}$, and N$_{2}$. There are no commercially available gas analyzers sensitive enough to detect these impurities at the low levels required by these detectors ($<$1 ppb). In order to reach the required impurity detection limits we will customize a Cavity Ring-Down Spectroscopy system. CRDS involves trapping monochromatic light between two highly reflective super-mirrors placed on both sides of the sample chamber, leading to an extremely long ($>$1 km) effective path length through the sample. By comparing the decay rates of light intensity at a resonance frequency of the impurity with that of light that is off-resonance, the concentration of absorbing material (the impurity) is obtained. We will gain improved sensitivity over existing technology by lengthening the gas cavity, optimizing the gas-flow routes, and enhancing the laser and detection electronics. The BHSU CRDS system will first be used for the depleted argon-based dark matter detectors DARKSIDE and MAX. The system will then also be available for xenon-based dark matter detectors such as LUX. This system may also be of interest commercially. [Preview Abstract] |
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D1.00012: Numerical Result of Supersymmetric Klein-Gordon Equation. Plausible Observation of Supersymmetric-Meson Victor Christianto, Florentin Smarandache In the context of some recent papers suggesting CT-symmetric QM in order to generalize PT-symmetric QM, in this paper we present an idea that there is quite compelling reasoning to argue in favor of supersymmetric extension of Klein-Gordon equation. Its numerical solutions in some simplest conditions are presented. Since the potential corresponding to this supersymmetric KGE is neither Coulomb, Yukawa, nor Hulthen potential [2a], then one can expect to observe a new type of matter, which may be called ``supersymmetric-meson.'' Its presence may be expected in particular in the process of breaking of Coulomb barrier in low energy schemes. Further observation is of course recommended in order to refute or verify this proposition. [Preview Abstract] |
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D1.00013: A Dynamic Analysis of Secretory Granules Containing Proteins Involved In Learning Louis Prahl, Alex Simon, Conor Jacobs, Audrey Fulwiler, Lindsay Hilken, Bethe Scalettar, Janis Lochner Formation and encoding of long-term memories requires a series of structural changes at synapses, or sites of neuronal communication, in the hippocampus; these changes are mediated by neuromodulatory proteins and serve to strengthen synapses to improve communication. Two prominent neuromodulators, tissue plasminogen activator (tPA) and brain-derived neurotrophic factor (BDNF), are copackaged into secretory granules (SGs) in the body of nerve cells and are transported to distal synapses by motor proteins. At synapses, particularly presynaptic sites, the fate of tPA and BDNF is largely unknown. Motivated by this, and by recent data implicating presynaptic BDNF in early phases of learning, we used fluorescence microscopy to elucidate dynamic properties of presynaptic tPA and BDNF. We find that presynaptic SGs containing tPA and/or BDNF undergo Brownian and anomalous diffusive motion that, in 75{\%} of cases, is so slow that it typically would be classified as immobility. These results suggest that tPA and BDNF are retained at presynaptic sites to facilitate their corelease and role in learning. [Preview Abstract] |
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D1.00014: Precise Color Tuning via Hybrid Quantum Dot Light-Emitting Electrochemical Cells Amanda Norell Bader, Anton Ilkevich, Janelle Leger Quantum dots (QDs) are of much interest as the active emitter in an organic light-emitting device due to their size-tunable band-gap energies, allowing device color to be carefully tuned over the entire spectrum by simply varying the size of QDs used. Colloidal QDs are compatible with solution processing techniques used to fabricate polymer light-emitting devices, resulting in inexpensive, low temperature, large area device fabrication on flexible substrates. QDs are more stable and have higher photoluminescence efficiency than organic emitters, but their efficacy in a typical polymer LED is limited by an insulating surface ligand layer that presents a charge tunneling barrier. This leads to unwanted emission from the polymer host material. A light-emitting electrochemical cell (LEC) structure presents a novel solution to this problem by limiting the emissive region thickness in the polymer/QD film. Emission spectra of QD-LECs composed of a two different sizes of QDs blended into a single polymer film show better color purity than polymer-only LECs, with nearly pure emission from the QDs. Relative intensity of the two narrow QD emission peaks is precisely controlled by varying the mass ratio between the QDs, directly changing device color. This novel QD-LEC structure has the potential to improve the performance of polymer optoelectronic devices, particularly in solid-state lighting. [Preview Abstract] |
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D1.00015: Nanoporous platinum: synthesis via dealloying Nathan Abrams, Aditya Abburi, W.J. Yeh Nanoporous structures with high active surface areas are critical for a variety of applications. We demonstrate the synthesis of nanoporous platinum thin films by dealloying. Dealloying is a corrosion process in which one or more elements are selectively removed from an alloy leading to a 3-dimensional porous structure of the more noble element. Cu$_{80}$Pt$_{20}$ films ($\sim $100--250~nm thick) are formed by cosputtering and dealloyed in aqueous H$_{2}$SO$_{4}$ solutions to selectively remove copper while allowing self-assembly of platinum into a nanoporous structure. The platinum nanoporous layers have a pore size of 20--100~nm, a surface area enhancement $>$20 times. Applications for these structures range from high surface area electrodes for biomedical sensors to use as skeletal structures for fundamental studies (e.g. low temperature heat exchangers or sensitivity of surface diffusivity to chemical environment). In this work we will review our current method of synthesis of the alloy thin film and include our most recent results demonstrating porosity in Pt. [Preview Abstract] |
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D1.00016: Polarization dependence of Landau parameters for normal Fermi liquids in two-dimensions David Li, Roger Anderson, Michael Miller Landau's formulation of his normal Fermi liquid theory was a key development in condensed matter and nuclear physics permitting one to describe the behavior and properties of a class of strongly interacting fermions with just a handful of microscopic parameters. We shall examine an application of normal Fermi liquid theory to two-dimensional fermion systems with a finite polarization. Two dimensional systems have practical importance as thin films, devices, and possibly models for certain high T$_{c}$ superconductors. Two dimensions offers one important theoretical advantage: the constant density of states permits calculations to be done exactly which in three dimensions would not be possible. In a low density approach we shall calculate exact, analytic expressions to quadratic order in the s-wave and p-wave interaction parameters for the basic Landau parameters, $f^{\uparrow \uparrow},f^{\uparrow \downarrow },f^{\downarrow \downarrow }$. This will enable us to study the polarization dependence of the state-dependent effective masses, the spin susceptibility, the compressibility, zero sound and spin-zero sound. Application of these results is made by studying and predicting the polarization properties of thin ${ }^3$He films. [Preview Abstract] |
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D1.00017: Study on bulk nanostructured MnBi permanent magnet prepared by spark plasma sintering Dongtao Zhang, Suai Cao, Ming Yue, Weiqiang Liu, Jiuxing Zhang, You Qiang In this paper, we report on the structure and magnetic properties of bulk nanostructured Mn100-xBix (x = 40, 45, and 52) permanent magnets prepared by spark plasma sintering (SPS) technique. Effect of Mn/Bi ratio on the MnBi low temperature phase (LTP) formation and magnetic properties of the magnets was investigated. Increase of bismuth amount in the synthesized magnets leads to better formation of LTP, resulting in the improvement of both magnetization (at 2 Tesla) and ramanence, but reducing the coercivity of the magnets. Ms increases from 27.87 emu/g for Mn60Bi40 to 45.31 emu/g for Mn48Bi52, while the coercivity decreases from 10.5 kOe to 7.87 kOe at room temperature. For the Mn48Bi52 magnet, TEM observation shows that its microstructure is composed of fine and uniform grains with an average size of 140 nm. The density of the magnet is 8.7g/cm3, which is over 93\% of its theoretical density. Further magnetic measurement at 423 K shows that the Mn60Bi40 magnet possesses a high coercivity of 19 kOe, indicating a strong positive temperature coefficient of coercivity of the bulk nanostructured MnBi permanent magnets. [Preview Abstract] |
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D1.00018: Plasmon Polariton Modes in High Index Dielectric Structures Trevor Morgan, Matt Oostman, Zach Graeber, Brad Johnson, Steve McDowall, Janelle Leger The need to interface optical signals with increasingly small electronic components has led to an interest in subwavelength waveguides. Waveguides based on the excitation of surface plasmon polaritons (SPPs) are promising for short-range applications. However, in these structures Ohmic damping significantly limits propagation length. High index dielectric plasmon polariton modes (HID-PPMs) are surface-constructed waves that exist in structures having a core dielectric layer with a higher refractive index than the glass substrate. Modes in this region exhibit oscillatory electric fields with the bulk of their electric field confined in the dielectric layer, similar to a TIR waveguide. Damping losses may therefore be drastically reduced in such structures. Unlike TIR waveguides, HID-PPMs can be excited along the full length of the waveguide, improving device versatility. Here we report the observation of HID-PPMs in Au/TiO2/Au structures using attenuated total reflection measurements. Results are in good agreement with theory. Waveguides based on HID-PPMs have the potential to improve a broad range of applications which rely on low loss energy transmission or compatibility with nanoscale components, such as telecommunications, optical signal processing, and solar concentration. [Preview Abstract] |
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D1.00019: Production and Rare Earth Doping of Aerogels Genderzon Montejo, Freddy Sanchez, Dylan Wenzlau, Kurt Hoffman We present recent studies into several methods for making Aerogels. We used both critical point drying methods and chemical dehydroxylation to achieve low density glasses. We used an SEM to characterize the increased pore sizes in these glass materials. In addition, we will present preliminary results of our efforts to add rare earth ions to the glass structure. We are attempting to add the rare earth ions to the glass while avoiding the clustering problems normally encountered in the sol-gel synthesis technique. [Preview Abstract] |
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D1.00020: Energy Transfer Studies of Tb Doped Sol-gel glasses Freddy Sanchez, Genderzon Montejo, Dylan Wenzlau, Kurt Hoffman We present recent studies of the effects of energy transfer on the time evolution of Tb$^{3+}$ emission lines in sol-gel glasses. Utilizing a multichannel analyzer we are now able to measure the lifetimes of weak emission lines from the sol-gel glasses. The measured decay signals have been analyzed using theoretical models to gain insight into the distribution of the rare earth ions in doped glasses. We will discuss the observed energy dynamics as the result of chemical treatments of the glass and fabrication variables. [Preview Abstract] |
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D1.00021: Fractal Conductance Fluctuations in Electron Billiards: The Nonlinear Regime Ian Pilgrim, Billy Scannell, Matthew Fairbanks, Rick Montgomery, Heiner Linke, Richard Taylor As the characteristic length scale of electronic devices continues to shrink, it is becoming increasingly vital to develop robust models for conduction properties on the mesoscopic scale. In contrast to both the diffusive electron transport processes of the classical world and purely quantum mechanical descriptions of electrons, we treat scales at which electrons may be thought of as following classical trajectories but whose conduction behavior depends on quantum coherence effects. We find that magnetoconductance fluctuations in electron billiards exhibit fractal qualities that reliably follow an empirical pattern in the regime of low applied bias, but which deviate from such behavior in the high-bias regime in not-yet-understood ways. [Preview Abstract] |
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D1.00022: Partners in Science Research Grant Leonard C. ``Chuck" Smith The M.J. Murdock Trust offers a {\$}15,000 Research Grant for High School Science Teachers to partner with a Researcher for two summers of research. Over 400 of these grants have been awarded in the 5 Northwest States since 1990. A supplemental grant to the high school may follow upon accepted application. The purpose of these grants is to promote scientific inquiry practices in the high school setting and to encourage students to consider a career in science. [Preview Abstract] |
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D1.00023: Attitudes toward physics Jaren Olsen This poster outlines the results of a diagnostic test given to Physics 105 students at the beginning and end of the class. Using the t test, it is shown whether factors such as gender, previous math experience and whether the class is required for the student's major affect a student's attitude toward physics. Also, the effect of the Physics 105 class itself on attitude toward physics can be seen by the comparison of the pre-test with the post-test. [Preview Abstract] |
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D1.00024: Promoting Metacognition in Introductory Calculus-based Physics Labs Drew Grennell, Andrew Boudreaux In the Western Washington University physics department, a project is underway to develop research-based laboratory curriculum for the introductory calculus-based course. Instructional goals not only include supporting students' conceptual understanding and reasoning ability, but also providing students with opportunities to engage in metacognition. For the latter, our approach has been to scaffold reflective thinking with guided questions. Specific instructional strategies include analysis of alternate reasoning presented in fictitious dialogues and comparison of students' initial ideas with their lab group's final, consensus understanding. Assessment of student metacognition includes pre- and post- course data from selected questions on the CLASS survey, analysis of written lab worksheets, and student opinion surveys. CLASS results are similar to a traditional physics course and analysis of lab sheets show that students struggle to engage in a metacognitive process. Future directions include video studies, as well as use of additional written assessments adapted from educational psychology. [Preview Abstract] |
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D1.00025: Cluster-Cluster Aggregation Calculations of Fractal Haze Particles: Titan and the Early Earth Bernice Terrell-Martinez, David Boness The atmosphere of the Archean Earth (3.8 to 2.5 billion years ago) is thought to have been dominated by a thick hydrocarbon haze similar to that of Titan's current atmosphere. To understand radiative transport in the atmospheres of the early Earth and of Titan, it is necessary to compute light scattering in UV, visible, and IR wavelength ranges for realistic fractal aggregate hydrocarbon aerosol particles. We report preliminary work on MATLAB, True BASIC, and Fortran programs to simulate the growth of fractal aggregate aerosols through diffusion limited aggregation (DLA) and cluster-cluster aggregation (CCA) physical processes. The results of these computations are being used with a T-Matrix light scattering program to test recently published, widely-reported conclusions about the early Earth and the faint young Sun paradox [E. T. Wolf and O. B. Toon, {\it Science} 328, 1266 (2010)]. This modeling is also relevant to understanding atmospheric carbonaceous soot aerosol anthropogenic and natural effects on climate change of Earth today. [Preview Abstract] |
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D1.00026: Isochronous chaos synchronization of delay-coupled optoelectronic oscillators Christian Panda, Lauren Shareshian, Lucas Illing We study experimentally chaos synchronization of nonlinear optoelectronic oscillators with time-delayed mutual coupling and self-feedback. A single such optoelectronic oscillator can generate a wide range of dynamical behaviors, including fast and high-dimensional chaos. Coupling three oscillators in a chain, we find that the outer two oscillators always synchronize isochronally. In contrast, isochronous synchronization of the mediating middle oscillator is found only when certain matching conditions for the time delays and coupling strengths are satisfied. Our experimental results are in good agreement with theory. [Preview Abstract] |
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D1.00027: The dynamics of the Malkus water wheel Alison Saunders, Rachel Fordyce, Lucas Illing The Malkus water wheel is a mechanical system whose chaotic dynamics are described by the famous Lorenz equations. In our experiment, a continuous series of syringes are attached to a bicycle wheel that can be inclined. Water pours into the wheel at the wheel's top and tunable friction is introduced through magnetic inductance braking. We successfully generate fixed point, periodic, and chaotic motion by tuning the wheel parameters, such as the braking torque, the inflow rate, and the angle of inclination. Upon mapping the experimentally measured parameters onto those of the model, we find that the wheel's behavior agrees reasonably well with that of the Lorenz equation. [Preview Abstract] |
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D1.00028: DC State of Mind; A Congressional update Kristopher Larsen Every day the headlines are dominated by news of a slow economic recovery, high unemployment, and a Congress focused on the next election. Deficit hawks, Tea Partiers, partisanship, and mid-term elections are all topics typically outside the ken of physics but are critically important to our ability to continue to pursue cutting edge innovative research. For example, during the last six months Congress has, among other things, worked on passing the 2011 federal budget and reauthorization of America COMPETES. Both of these major pieces of legislation are fundamental to how our country will fund physics research for the next few years. For the past two years, science has done very well thanks to the support of Congress and the administration. The coming years are going to be far more difficult and every physicist needs to commit themselves to defending the gains we have made. This poster will provide an overview of what has happened on Capitol Hill in the past few months and what, to the best of our knowledge, the physics community can expect for the coming years. The legislative successes of the last few months couldn't of happened without the aid of physicists who got involved. Around the country, physicists wrote opinion pieces for their local papers, wrote letters-to-the-editor, called their representatives, made their voices heard and helped shape policy. [Preview Abstract] |
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D1.00029: Investigations of the Stabilizing Osmolyte, TMAO, as a New Precipitant for Protein Crystallization Haley Marshall, Murugappan Venkat, Douglas Juers Osmolytes, organic compounds used by organisms to maintain osmotic balance, are known to modulate the solution behavior of proteins, in some cases increasing stability. Due to the nature of protein crystallization and the need for stable proteins to produce crystals, osmolytes could prove to be useful agents for crystallization. In this study, we demonstrate the potential of trimethylamine N-oxide (TMAO), a common osmolyte, as a crystallization agent. TMAO was successfully used to grow a total of eight different crystal forms of five different proteins. Furthermore, the crystals produced with TMAO as the crystallization agent were comparable in quality, morphology and their ability to diffract X-rays to crystals grown with previously identified crystallization conditions. We therefore expect the efficacy of TMAO as a crystallization agent will extend to other proteins systems and suggest that, due to its stabilizing effect on protein structure, TMAO may be a good alternative screening agent for protein crystal growth. [Preview Abstract] |
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D1.00030: Density law of gravity and earthquakes, tsunamis, landslides, the universe Han Yongquan Earthquakes, tsunamis and landslides are the main reasons as a part of the density of Earth's interior is extremely strong gravity, atomic energy was collapsed to form a new larger atomic nuclei, in fact, nuclear fusion reaction, fusion increases its density, density, gravity also increased release and because a large number of nuclear fusion energy. Was collapsed in the number of atoms is large, the gradual formation of large voids. Collapsed when the atoms are combined into a new atom, according to the new atomic theory, bare nuclei, due to extremely high temperatures nuclei, theoretical calculations will be released in $2.6\times 10^8 {^\circ}$C enormous energy, so it will form a special high-energy, or temperature especially high, particularly in the energy group pressure, high energy, this energy reaches a certain group of energy must be released when: the energy of the ground under very high energy group, on the formation of the earthquake; in the sea of energy under very high energy group, the formation of the tsunami; in the mountains of energy under very high energy group, on the formation of landslides. I am a teacher working in Chawu Railway Middle School, Huairou District, Beijing, China (Postcode: 101402). [Preview Abstract] |
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D1.00031: Review of Two Game Changing Technologies for Space Mission Application Patricia Randazzo As technology continues to move forward, many new developments and products become available and can be considered for application in NASA's space missions. Two game changing technologies are high temperature superconductors (HTSC) and ionic polymer-metallic composite (IPMC) actuators and sensors. High temperature superconductors are a metal or alloy that can be cooled to above 70 K and are able to conduct an electric flow with zero resistance. Ionic polymer-metal composites actuators and sensors are synthetic composites that display artificial muscle behavior under an applied voltage. By conducting research to review papers, attending lectures and conferences, and interviewing and meeting with developers and researchers many products and applications for specific use in space missions were found. HTSC technology is being integrated into rocket propulsion and acceleration, radiation shielding, energy storage and medical diagnostic tools. IPMC technology is being integrated into extreme environment robotics, avionics and motion detection. [Preview Abstract] |
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D1.00032: Research and Development for Underground Science at Black Hills State University Kara Keeter The development of the Deep Underground Science and Engineering Laboratory (DUSEL) in the former Homestake mine in Lead, South Dakota has greatly spurred interest in science research and development along with education and outreach. Early science activities at Black Hills State University associated with the Sanford Underground Laboratory and DUSEL include radon emanation studies of iron oxide sludge and in situ, and radioactive background and magnetic field measurements. Work is also underway for R{\&}D development for depleted argon-based dark matter detectors, neutrinoless double beta decay experiments, and a liquid scintillator immersion tank for whole-body low-background assays. Students from BHSU and across the state of South Dakota have been working alongside scientists on these and other projects. Teachers from high schools throughout South Dakota have also participated in these projects through the newly formed QuarkNet Center at BHSU. [Preview Abstract] |
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D1.00033: Tensile Bond Strength of Latex-Modified Bonded Concrete Overlays Cameron DuBois, Chris Ramseyer The tensile bond strength of bonded concrete overlays was tested using the in-situ pull-off method described in ASTM C 1583 with the goal of determining whether adding latex to the mix design increases bond strength. One slab of ductile concrete (f'c $>$ 12,000 psi) was cast with one half tined, i.e. roughened, and one half steel-troweled, i.e. smooth. The slab surface was sectioned off and overlay mixtures containing different latex contents cast in each section. Partial cores were drilled perpendicular to the surface through the overlay into the substrate. A tensile loading device applied a direct tensile load to each specimen and the load was increased until failure occurred. The tensile bond strength was then calculated for comparison between the specimens. [Preview Abstract] |
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D1.00034: Fermi Liquid Description of X-ray Absorption Spectra in Overdoped LSCO Towfiq Ahmed, John J. Rehr, Joshua J. Kas, Tanmoy Das, Hsin Lin, Robert S. Markiewicz, Bernardo Barbiellini-Amidei, Arun Bansil We show that a paramagnetic self-energy correction [1] to the real-space Greens function code FEFF9 [2] can provide a good description of the x-ray absorption spectra (XAS) of cuprate system such as $La_{2-x}Sr_xCuO_4$ (LSCO). This self-energy includes coupling to the both charge and magnetic excitations. We also find good agreement with recent XAS results of Peets $et al$ [3] in the over-doped regime of LSCO. We have also investigated various prescriptions for including core-hole effects. We infer that at low-doping, the system behaves as an anti-ferromagnetic insulator, while Fermi liquid physics is recovered at high doping. [1] Tanmoy Das, R.S. Markiewicz, and A. Bansil, Phys.Rev. B {\bf {77}}, 134516 (2008). [2] J.J. Rehr $et al.$, Comptes Rendus Physique {\bf {10}}, 548 (2009). [3] D.C. Peets $et al.$,Phys. Rev. Lett {\bf {103}}, 087402 (2009). [Preview Abstract] |
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D1.00035: Dynamic and static fluorescence quenching of bovine serum albumin Jacob Friday, Jeremiah Babcock, Lorenzo Brancaleon Protein folding dynamics studies can benefit from the knowledge of specific binding-site availabilities, which aid the detection of protein structural changes and, possibly, protein structure. Fluorescence quenching (FQ) spectroscopy can be used to detect binding site variations arising from evolving protein conformational changes over time. Use of the Stern-Volmer and modified Stern-Volmer equations shows the divergence of the bimolecular quenching constant from the diffusion-limited constant, which can be indicative of bimolecular binding. The study is part of a larger effort to understand early structural events that lead to the aggregation of partly unfolded proteins. In this study, bovine serum albumin (BSA), a globular alpha-helix plasma transport protein, was complexed with the fluorescent ligand fluorescein in phosphate buffer at pH 7.4 and subjected to FQ spectroscopy. Stern-Volmer plots demonstrated an upward quadratic relationship, indicating the presence of dynamic and static quenching factors. Data-fitting showed that multiple binding sites were available. With these results, further studies will be undertaken, where BSA will be subjected to varied denaturing conditions, including pH changes and urea solvent addition. The change of available binding sites could reveal BSA structural patterns. [Preview Abstract] |
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