Bulletin of the American Physical Society
2016 Annual Spring Meeting of the APS Ohio-Region Section
Volume 61, Number 5
Friday–Saturday, April 8–9, 2016; Dayton, Ohio
Session B1: Poster Session (4:15 pm - 5:30 pm) |
Hide Abstracts |
Chair: Mo Ahoujja, University of Dayton Room: Meyer Room |
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B1.00001: ABSTRACT WITHDRAWN |
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B1.00002: Magnetic and magnetocaloric properties of Mn$_{\mathrm{5-x}}$Co$_{\mathrm{x}}$Ge$_{\mathrm{3}}$ compounds Miranda Caudle, Barrett Fitzgerald, Brian Knauf, Eli Shlonsky, Patrick Carroll, Lindsay Darkins, Adam Eaton, Matthew Rurka, Amber Williams, Paul Wilson, Jeffrey Brock, Mahmuh Khan Mn$_{\mathrm{5}}$Ge$_{\mathrm{3}}$ exhibits a Curie temperature of 296 K and has been reported to have a magnetic entropy change comparable to that of pure Gd, which makes it a potential candidate for near room temperature magnetic refrigeration applications. In this study we have synthesized and characterized a series of Mn$_{\mathrm{5-x}}$Co$_{\mathrm{x}}$Ge$_{\mathrm{3\thinspace }}$compounds where x$=$0, 0.05, 0.1, and 0.15. The goal is to determine the effect of Co substitution for Mn on the magnetic and magnetocaloric properties of the materials. X-ray diffraction measurements revealed that all samples exhibit the D8 hexagonal structure at room temperature. Magnetization measurements show that all compounds exhibit ferromagnetism, with a decrease of Curie temperature with increasing Co concentration. Although, the magnetic entropy changes stays nearly constant across all values of x, Co substitution significantly enhances the refrigeration capacity of the materials. The largest magnetocaloric effect is observed in the Mn$_{\mathrm{4.95}}$Co$_{\mathrm{0.15}}$Ge$_{\mathrm{3}}$ compound with a peak magnetic entropy change of 7.75 J/kg K and a peak refrigeration capacity of 380.32 J/kg for a magnetic field change of 5T. The results provide further understanding of potential magnetocaloric applications for this series of compounds. [Preview Abstract] |
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B1.00003: Of annealing on the microstructure and magnetic properties of selected (Ni-Mn-Ga) melt-spun ribbons Ohud Alshammari, Mahmud Khan Permanent magnets based on rare earth metals are in the central part of commercial use. However, the increasing demand of theses magnets and the limited availability of rare earth elements is causing continues increase in the pricing of these magnets. Therefore, the need of developing cheaper non-rare earth based permanent magnets is of great importance. Here we present the results of our experimental investigations on the melt spun ribbons of selected Ni-Mn-Ga based inter-metallic compounds. The result show that the microstructure and associated magnetic properties of the ribbons can be controlled by annealing techniques. The coercive field varies strongly with the annealing conditions, and the materials also exhibit exchange bias behavior that can be exploited to develop new permanent magnets. [Preview Abstract] |
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B1.00004: More climate myths Gordon Aubrecht This continues my series of posters on climate myths [Preview Abstract] |
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B1.00005: Light-sensitive reaction-diffusion waves in a checkerboard-like illumination system. Spencer Kirn, Niklas Manz We will report about a set-up to experimentally investigate the propagation behavior of excitation ~waves traveling through an inhomogeneously illuminated reaction-diffusion medium, including preliminary results.~Schebesch and Engel (I. Schebesch and H. Engel, \textit{Wave propagation in heterogeneous excitable media}, Phys. Rev. E, \textbf{57}(4), 3905--3910, 1998) calculated numerically the propagation behavior of light-sensitive excitation waves in a pure checkerboard-like illuminated system. We are using the model system of excitable media, the chemical~Belousov-Zhabotinsky (BZ) reaction, to verify their one-dimensional and two-dimensional results.~ [Preview Abstract] |
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B1.00006: Design and Construction of a Telescope Mounted Spectrograph London Bortell, Craig Howald For this project, a spectrograph intended for measuring emissions of variable stars was designed and constructed. The design is composed of a single slit, a collimator, a diffraction grating, a camera lens, and an imager which are all mounted on an aluminum extrusion rail. Design calculations were performed to find reasonable parameters for each part based on commercial availability and the desired capabilities of the spectrograph. Sample spectra of emission lamps were used to verify acceptable performance of this spectrograph. Soon the spectrograph can be attached to our 14 inch reflecting telescope to begin astronomical measurements. [Preview Abstract] |
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B1.00007: Designing and Building a Combined Atomic Force and Scanning Tunneling Microscope Cheng Jie Gu, Craig Howald We report the design and construction of a combined atomic force microscope and scanning tunneling microscope (AFM/STM). Materials used were constrained to all be ultrahigh vacuum (UHV) compatible and for all structural materials to have similar thermal expansion coefficients thus minimizing thermal drift. In addition, significant effort was made to design for a high value of the lowest resonant frequency in order to reduce vibrational noise and its effects on the measurement quality. The coarse approach is accomplished with sequential elongation and contraction of three longitudinal segments on a piezoelectric tube. Using an interferometer, we verified that the sliding piece which carries the tip can be moved relative to the three segment tube on both nanometer and millimeter scales. Successful imaging in scanning tunneling mode is also shown. [Preview Abstract] |
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B1.00008: MD Simulations of the Condensation of Carbon Atoms for Comparison with Graphitic Stardust Lindsay Lesh, Eric Mandell The objective of this research is to simulate the quenching (rapid-cooling) of carbon droplets of various sizes with various quench times for comparison with graphitic stardust found in primitive meteorites. The meteoritic carbon formations of interest exhibit a core-rim structure, where the core -- with a density less than that of the graphitic rim -- comprises the majority of the grain. There is reason to hypothesize that the cores of these grains are the result of the rapid freezing (quenching) of a liquid carbon droplet. Since the liquid phase of carbon is extremely difficult to investigate in laboratory conditions due in part to its high melting point, molecular dynamic simulations are an attractive method for examining the behavior of carbon as it is rapidly cooled from a gaseous state. The resulting condensates from these simulations have been analyzed using radial distribution function (RDF) calculations and debye scattering calculations to simulate electron diffraction data. [Preview Abstract] |
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B1.00009: Modeling Effusive Gas Doser Arrays for Surface Science Experiments Jonathan Kadowaki, Dennis Kuhl Effusive gas doser designs necessary for surface science experiments were computationally modeled using Python. Four, five and eight hole effusive doser arrays were modeled to give their effective enhancement and area-weighted standard deviation in flux at the surface of a rectangular thin metal film. More holes closer to center of the sample provide better enhancement at the cost of uniformity. Uniformity tends to vary with different doser-to-sample distances and hole patterns. The four hole and one of the eight hole patterns exhibited local minima in their area-weighted standard deviation in flux at particular doser-to-sample distances, indicating strong uniformity there. By moving the holes of the pattern outward we can increase the sample-to-doser distance at which this minimum occurs. [Preview Abstract] |
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B1.00010: MUPALS -- Miami University Positron Annihilation Lifetime Spectrometer Md Salah Uddin, Herbert Jaeger A spectrometer for measuring positron lifetimes in solids is described. It consists of a pair of BaF$_{\mathrm{2}}$ scintillators coupled to photomultiplier tubes and a fast-slow delayed coincidence system composed of standard NIM modules. The instrumental resolution curve as determined with a $^{\mathrm{60}}$Co source is well-described by a Gaussian with a full-width at half-maximum of approx. 300~ps. We used this apparatus to determine the lifetimes of positrons in commercial grade Al and PTFE (Teflon) at room temperature with a $^{\mathrm{22}}$Na positron source enclosed in Kapton$^{\mathrm{\mbox{\textregistered }}}$ foil. Both samples show a lifetime component in the 350--450 ps range. While the PTFE sample has a long component near 2 ns, the Al sample has a short (approx. 200 ps) as well a long component (\textgreater 2 ns). [Preview Abstract] |
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B1.00011: SiC Diodes with Ti Schottky Contacts Deposited at Different Temperatures. Krishna Kundeti, Tom Oder Commercial silicon carbide semiconductor diodes are fabricated using Ti as the Schottky contact metal. In this study, we investigated the properties of the diodes fabricated with Ti deposited at different temperatures ranging from 30 $^{\mathrm{o}}$C to 900 $^{\mathrm{o}}$C. The goal of this study is to improve the performance of the diodes by optimizing the fabrication process. Thin films of Ti were deposited on SiC using magnetron sputtering and characterized using current-voltage measurements. Preliminary results suggest the diodes with Ti deposited at 200 $^{\mathrm{o}}$C yield better devices with ideality factor of 1.05 and Schottky barrier height of 1.00 eV. Additional thermal processing and physical characterization is underway and these results will be reported at the presentation. [Preview Abstract] |
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B1.00012: Effects of low-dose high-energy photon irradiation on UHMWPE films Nenad Stojilovic, Sasa Dordevic, Strahinja Stojadinovic Irradiation of biocompatible polymers is generally performed using high-dose gamma radiation, typically in kGy-to-MGy range. In this study, ultra high molecular weight polyethylene (UHMWPE) films have been exposed to relatively low dose (30, 60, and 120 Gy) radiation, utilizing 6 MeV clinical linear accelerator X-Rays. The impacts of irradiation were compared with the pristine UHMWPE films. The effects of low-dose 6 MeV photon irradiation were investigated using X-Ray Diffraction method, Fourier Transform Infrared, Ultraviolet-visible and Fluorescence spectroscopy. We discuss radiation-induced changes in the optical properties and interplanar spacing, and propose mechanisms responsible for the observed changes. [Preview Abstract] |
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B1.00013: Impact of Growth Temperature and Post Growth Annealing on the Electrical Properties of InAs/InGaSb Superlattice Structures. Arthur Siwecki, Henry Bourassa, Mo Ahoujja, Said Elhamri, Heather Haugan, Gail Brown, Shin Mou, William Mitchel Infrared detector research has been the focus of several research groups worldwide. This intense interest arises from the many possible commercial applications of these devices. One of the important materials being investigated for such an application is the InAs/InGaSb superlattice structure. A key advantage of this material is that its detection wavelength can be tailored by varying the thicknesses of the layers constituting the superlattice structure. To fully exploit the full potential of the InAs/InGaSb superlattice structure in the area of infrared detection, it is paramount that its electrical behavior is fully understood. A key goal for all researchers in this area is a reduction in the background carrier density in these structures. It is well established that a high background carrier density degrades device performance. Growth conditions have a significant impact on the level of this density. In this study, we will report results of transport measurements conducted on several samples to evaluate the impact of sample growth temperature and post growth annealing on the carrier density and mobility of these superlattice structures. [Preview Abstract] |
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B1.00014: A Model for Mobility Analysis in Semiconductors. Henry Bourassa, Arthur Siwecki, Mo Ahoujja, Said Elhamri The Hall Effect measurements have long been the standard electrical characterization technique to extract the free carrier concentration and carrier mobility as a function of temperature in semiconductors. Analysis of the measured mobility shows that the mobility is affected by different scattering mechanisms. In this project, a model of the different scattering mechanisms due to acoustic mode, polar-optical mode, piezoelectric and ionized impurity is considered using Mathcad, a computer software. The model will be applied to a mobility data measured on GaN, a wide bandgap semiconductor used in optoelectronic devices such as UV detectors and blue laser diodes. [Preview Abstract] |
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B1.00015: Development of an Apparatus for Measuring the Nernst Effect in Semiconductors Jeffrey S. Dyck, Christopher J. Wrenn An apparatus for measuring the Nernst Effect in bar-shaped semiconductor samples was designed. The Nernst Effect is a key thermoelectric effect used to understand transport properties of materials. Measurement of this phenomenon is part of ongoing research to understand Bi$_{2}$Te$_{3}$-based nanostructured materials, specifically, characterization of the details of the charge carrier scattering mechanisms in these materials. A special sample mount was designed to accommodate semiconductor samples that are only a few millimeters in size, and that can position the sample perpendicular to both an applied magnetic field and an imposed temperature gradient, as required to measure the effect. Further, the entire measurement takes place inside a small cryostat enclosure, enabling measurements from room temperature down to 7 K. The apparatus was used to measure the Nernst Coefficient in a sample of germanium as a proof of concept since such values are easily found in literature. The measurement yielded a Nernst Coefficient of -316 $\mu V/KT$ at room temperature. This value is within 5{\%} of the value from literature, confirming that the apparatus works as hoped. [Preview Abstract] |
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B1.00016: Bottom-Up Wet Chemical Synthesis of Nanostructured Materials from the Infinitely Adaptable Bismuth Telluride Series Daniel J. Volpe, Jeffrey S. Dyck, Paul C. Challen, Virgil C. Solomon Novel thermoelectric materials are necessary to solve the looming energy crisis, because they can convert waste heat into usable energy. Bismuth-telluride-based compounds are the focus of this study because of their very good room temperature thermoelectric properties, and they can be prepared in nanostructured forms, which is known to enhance the thermoelectric efficiency. Bismuth telluride nanopowder was synthesized from a bottom-up wet chemical approach with a yield of \textasciitilde 90{\%}. The starting reagent ratio was tuned to match the desired stoichiometry of the product, thus resulting in the identification phases from an infinitely adaptable series, (Bi$_{2})_{m}$(Bi$_{2}$Te$_{3})_{n}$ , where m,n are integer values. Relatively pure Bi$_{2}$Te, BiTe and Bi$_{2}$Te$_{3}$ independent phases were characterized through x-ray diffraction (XRD), scanning electron microscopy (SEM), inductively couple plasma atomic emission spectroscopy (ICP-OES) and energy dispersive x-ray spectroscopy (EDX). Lattice parameters were determined and found to be within 0.45{\%} of literature values of bulk-grown forms for these three compounds. [Preview Abstract] |
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B1.00017: Magnetic properties of selected Mn3-xFexGa compounds Abdul Quader, Dr. Mahmud Khan Permanent magnets are important components of many technologies including wind turbines and electric motors for hybrid vehicles. The most powerful permanent magnets are based on rare earth elements, many of which are critical due to supply and demand related issues. Considering the increasing demand of high performance permanent magnets and the shortage of rare earth elements, it is important to develop magnets that do not rely on these critical elements. Recent research shows that materials based on Mn3Ga may have strong potential as alternatives to rare earth metal based permanent magnets. Therefore, in this research we have investigated a series of Mn3-xFexGa compounds that were fabricated by arc meting and annealing techniques. The goal is to investigate the effect of Fe doping on the permanent magnetic properties of the compounds. The samples have been characterized by dc magnetization measurements at various temperatures and at magnetic fields of up to 5 T. A significant enhancement on the magnetic properties of the compounds has been observed. The experimental results suggest that the materials may be considered as potential candidates for further research. [Preview Abstract] |
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B1.00018: Molecular Spectroscopy of Diatomic Iodine Briana Vamosi, Matt Kelly, Jacob McFarland, Burcin Bayram We have measured the lifetime of the highly excited state (E$^{\mathrm{\prime }})$ of iodine diatomic molecule by using double-resonance two-photon pump-probe excitation technique. Our laser is a 6-ns tunable dye laser pumped by Nd:YAG solid state laser, operating at the second and the third harmonics simultaneously. Pulsed lasers are counter propagating and the detection is at the right angle to the propagation direction of the lasers. Analysis of the exponential decay of the cascade photons from the E (v$^{\mathrm{\prime }}=$3) to the B (v$^{\mathrm{\prime }}=$32) allows us to extract the lifetime and collisional cross section. [Preview Abstract] |
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B1.00019: Radiative Relaxation of Sodium Diatomic Molecules Tim Horton, Jacob McFarland, Burcin Bayram We have measured the radiative lifetime of the A$^{\mathrm{1}}\sum _{\mathrm{g}}$ (8,30) rovibrational level of sodium diatomic molecule by using a 6-ns tunable pulsed laser. Sodium dimers are created in a heatpipe oven at 300 K and argon is used as buffer gas. Analysis of the exponential decay of the cascade photons allows us to extract the lifetime of the rovibrational level. By varying the pressure of the heatpipe collisional cross section can be extracted. [Preview Abstract] |
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B1.00020: Four-wave mixing in Silicon waveguides Colleen Bransley, Imad Agha, Yun Zhao Four-wave mixing in silicon waveguides is a novel method of optical switching. In essence, three wave patterns are used to produce the optical switching effect. The first is a strong pump wave, the second is a weaker secondary pump and the last is a low power wave. The three waves are mixed in order to convert the signal to an idler. The switching functions by using the low power pump signal. When the low power signal is on the switch is on and when the low power signal is off the switch is off. All the input waves are triggered from the same source ~so that the switching is synchronous. In my work, I focus on how to generate the necessary input wave and how to lock them together [Preview Abstract] |
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B1.00021: Composition Dependent Majority Charge Carriers in Cobalt Iron Sulfide (Co $_{\mathrm{\mathbf{x}}}${Fe}$_{\mathrm{\mathbf{1-x}}}${S}$_{\mathrm{\mathbf{2}}}$) Pyrite Nanocrystals Ebin Bastola, Tyler Kinner, Khagendra Bhandari, Bradley Monahan, Neale Haugen, Paul Roland, Terry Bigioni, Randy Ellingson We report the hot-injection colloidal chemical synthesis, and characterization of cobalt (Co) doped iron pyrite (FeS$_{\mathrm{2}})$ nanocrystals (NCs). The synthesized alloyed Co$_{\mathrm{x}}$Fe$_{\mathrm{(1-x)}}$S$_{\mathrm{2}}$ pyrite NCs have been characterized by using X-ray diffraction(XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman, and UV-Vis-NIR spectroscopy. We discuss the electronic properties such as resistivity, mobility, carriers concentration of the NC thin films. Based on the hot-probe and Hall measurements, the iron pyrite (FeS$_{\mathrm{2}})$ NC thin films are p-type, and on doping these iron pyrite NCs with Co, the majority charge carriers changes from p-type to n-type in between the Co concentration of 16\% to 21\%. [Preview Abstract] |
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B1.00022: Cryogenically-Cooled, Microwave Bolometer based on Carbon Nanotube Thin Films Michael Gasper, Ryan Toonen, Samuel Hirsch, Mathew Ivill, Henning Richter, Ramesh Sivarajan We have used a carbon nanotube (CNT) thin film fashioned in a Corbino disc test structure to realize a cryogenically-cooled, microwave bolometer. We characterized the noise equivalent power (NEP) down to liquid nitrogen temperatures ($\sim$77 K). The detection mechanism relies on the microwave-power-sensitive resistivity of the CNT thin film. Using lock-in detection, room-temperature experiments (performed with 915 MHz test signals) showed power detection over the range of -45 dBm to 0 dBm--with 0 dBm being limited by the maximum level attainable from available equipment. A sensitivity of 0.36 mV/mW and an NEP of (3.41$\pm$0.96)$\times$10${}^{-7}$ W/$\sqrt{Hz}$ was achieved with a slightly-cooled device held at a constant temperature of 15${}^\circ$C. Lowering the base temperature of the device resulted in a greater dynamic range--due to the lower NEP. To demonstrate the possibility of using the Corbino effect as a means of tuning impedance matching for optimal performance, cryogenically-cooled magnetoresistance measurements were performed in the presence of a magnetic field (applied normal to the surface of the device) ranging from 0 to 3 T. [Preview Abstract] |
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B1.00023: The Quark-Hadron Phase Transition in Neutron Stars and Protoneutron Stars Jacob B. Roark Neutron stars have masses between 1.4 and 3 M$_{\odot}$, all packed into a sphere just 12 to 13 km across (roughly the size of Manhattan). Consequently, neutron stars exhibit some the of highest material densities in the universe, averaging around 7$\times$10$^{17}$ kg/m$^3$, over three times the density of an atomic nucleus. Under such astronomical pressures, some very interesting, novel states of matter can be achieved, such as quark matter, in which nucleons effectively dissolve and quark deconfinement occurs. In this project, the quark-hadron phase transition was studied for three different scenarios: neutron stars, neutron stars with mixed phases, and protoneutron stars (in which lepton fraction must be conserved). A quantum hadrodynnamic effective model based on the spontaneous breaking of chiral symmetry was employed to achieve this data, along with a mean field approximation. In each case, the point at which phase transitions no longer occur (the critical point) was found, characterized by temperature and baryon chemical potential. For neutron stars, the critical point was found to occur at T=168.82 MeV and $\mu_{B}$=230.05 MeV; for neutron stars with mixed phases, T=168.86 MeV and $\mu_{B}$=226.50 MeV; and for protoneutron stars, T=168.82 MeV and $\mu_{B}$=247.25 MeV. [Preview Abstract] |
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B1.00024: Newtonian and MONDian Stellar Orbits in a Spherically Symmetric Hernquist Density Profile Justin Messinger, Alexander Staron, Stephen Alexander Dwarf Spheroidal Galaxies (dSph) are small loosely bound collections of stars that are interesting test sites for models of dark matter or as regions where Newtonian gravity requires modification. We present a model that can be used to study the motion of stars in a dSph. The distribution of matter is described by a baryon cloud with a Hernquist density profile, and we explicitly calculate the motion of several thousand stars subject to the gravity from the cloud. We present sample orbits for both Newtonian and MONDian gravity that can be used to calculate velocity dispersions which can be compared to actual observations of dSph's. [Preview Abstract] |
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B1.00025: Bulk Velocity Dispersions and Dispersion Profiles for MW and Andromeda Dwarf Spheroidal Galaxies Matthew Walentosky, Benjamin Blankartz, Stephen Alexander We present the results of simulations of the motion of stars in Dwarf Spheroidal Galaxies (dSph's) using both Newtonian and MONDian gravity. For each simulation, we integrate the motion of ten thousand stars that interact with a baryon cloud described by a Hernquist density profile. Using the best observed properties of several Milky Way and Andromeda dSph's, we calculate the bulk dispersion for several values of the mass-luminosity ratio (M/L). When we find the value of M/L that gives a good match with the observed bulk dispersion, we use that value to produce a dispersion profile, i.e. the dispersion as a function of distance from the center of the galaxy. We compare our results to Milky Way dSph's for which observed profiles have been measured, and Andromeda dSph's for which only bulk dispersions are available. We find that MONDian gravity produces good agreement with observed profiles; whereas, Newtonian gravity (without dark matter) produces profiles that do not agree with observations. [Preview Abstract] |
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B1.00026: The Black Hole Mass in NGC 4258 from Gas Kinematics David DeColibus, Jason Pinkney NGC 4258 is an important galaxy for the demographics of supermassive black holes (SMBH). Radio (VLBA) observations of its nuclear disk of water masers has allowed a very precise estimate of the mass of the central SMBH (3.9$\pm0.1\times 10^7 M_{\odot}$), and the distance to the galaxy (7.2 Mpc). Hubble Space Telescope (HST) archival data allow the measurement of the BH mass in two independent ways: stellar and gas kinematics, providing a crucial test of these methods. Here we report on an analysis of the archival data which allow gas kinematics: STIS long-slit spectroscopy from two programs, a total of 6 slit positions. We have fitted the H$\alpha$ + [NII] and [SII] lines in order to determine radial velocities and velocity dispersions as a function of position along the slits. We use primarily the velocities to constrain our thin, inclined, gas disk models. We see evidence (in modeling and narrowband imaging) for a nuclear gas disk extending out to about 0.4'' (14 pc) which is greatly inclined relative to the galaxy's spiral disk. It may be unrelated to the maser disk (r$\sim$0.3 pc), given that it's major axis and inclination each differ from the maser disk by about 25 degrees. Our best models show a BH mass of 3-8$\times 10^7 M_{\odot}$, consistent with maser results. [Preview Abstract] |
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B1.00027: Room temperature lasing in GeSn alloys: A path to CMOS-compatible infrared lasers Zairui Li, Yun Zhao, James Gallagher, Imad Agha, José Menéndez, John Kouvetakis, Jay Mathews The semiconductor industry has been pushing silicon photonics development for many years, resulting in the realization of many CMOS-compatible optoelectronic devices. However, one challenge that has not been overcome is the development of Si-based lasers. Recently, GeSn alloys grown on Si have shown much promise in the field of infrared optoelectronics. These alloy films are compatible with CMOS processing, have band gaps in the infrared, and the band structure of GeSn can be tuned via Sn concentration to induce direct band gap emission. In this work, we report on room temperature emission in optically-pumped waveguides fabricated from Ge0.956Sn0.044 and Ge0.928Sn0.072 films grown epitaxially on Si(100) substrates. The waveguides were defined using standard UV photolithography and dry-etched in a Cl plasma. The end facets were mirror polished, and Al was deposited on one facet to enhance cavity quality. The waveguides were optically-pumped using a 976nm wavelength solid-state laser, and the corresponding emission was measured. The dependence of the emission power on the pump power shows the simulated emission is highly amplified and with higher Sn concentration sample shows shaper curve. [Preview Abstract] |
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B1.00028: Femoral bone strength in bipedal and quadrupedal dinosaurs. Scott Lee The section modulus Z measures the strength of a bone to resist bending torques. Such torques are more likely to break a bone than a compressive stress since they induce a tensile strain. We report the evaluation of the section modulus versus length for the femora of 94 theropods, 18 sauropods, 16 ceratopsians, 98 large mammals, and 95 small mammals. The largest theropod dinosaur is \textit{Tyrannosaurus rex} and the largest sauropod dinosaur is \textit{Dreadnoughtus schrani} with estimated masses of 7,000 and 40,000 kg, respectively. The largest \quad mammal is \textit{Loxodonta africana} (with a mass of about 5,500kg) and the mammal with the shortest femur is \textit{Herpestes griseus}. For these groups of animals, the section modulus Z is found to be related to its length L via a power law. The theropods, sauropods and large mammals all have the same exponent for the power law: about 3.48. The exponent is about 3.13 for the ceratopsians and about 2.83 for the small mammals. Possible explanations for these values of the exponent will be discussed. [Preview Abstract] |
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B1.00029: Application of statistical procedures based on mutual information in the protein Calbindin D-9k for detecting the allosteric pathways Mahendra Thapa, Mark Rance Calbindin D$_{\mathrm{9k}}$ (CAB) is a small (molecular weight of 8700 D with only 75 amino acids) calcium-binding protein that binds two calcium ions in a cooperative fashion at its two binding sites. It is an attractive model system for computational studies of various dynamical and structural properties such as the molecular basis of cooperativity of calcium binding, chemical shifts and fluctuations of atoms under a variety of conditions. Because of the tremendous advancement in hardware and software computer technologies in recent years, longer and more realistic molecular dynamics (MD) simulations of a protein are possible now in reasonable periods of time. These advances were exploited to generate multiple, all-atom MD simulations of CAB via the AMBER software package, and the results from the resulting trajectories were employed not only to compare with the corresponding experimental NMR results but also for the theoretical. Application of statistical procedures based on mutual information, via the GSATools and MutInf software, provided valuable insights regarding correlated motions between the two calcium binding loops of calbindin D$_{\mathrm{9k}}$ and identified residues that may play a direct role in the allosteric pathway. However, from our initial work in this area, it is not yet clear what the optimum protocol is for the application of the methodology. But even from the preliminary results we obtained, it is possible to design computational studies of mutant versions of calbindin D$_{\mathrm{9k}}$ in an effort to identify the physical mechanisms underlying the observed positive cooperativity of calcium ion binding. [Preview Abstract] |
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B1.00030: An Analogy to Phase Transitions for Fluid Flows in Rectangular Cavities. Petru Fodor, Miron Kaufman Using computational fluid dynamics we analyze the flow in rectangular cavities in which the fluid is driven by the motion of one of the boundaries defining the cavity. The high resolution mapping of the flow structures formed within the cavity reveals that in the vicinity of the stationary points corresponding to the cavity corners the streamline function, velocity fields and shear rates, follow scaling laws similar with those found for critical phenomena. In particular the behavior near corners defined by stationary walls is analogous to second order transitions. On the other hand at corners defined by one stationary and one moving wall the behavior corresponds to a first order transition. These analogies provide a new perspective on analyzing the solutions of the Navier-Stokes equations for cavity flows. [Preview Abstract] |
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B1.00031: Effect of impedance matching on dust clusters in a vertical rf plasma Andrew Kurtz, Terrence Sheridan We study properties of a radio-frequency (rf) plasma discharge created between vertical parallel plates, one conducting and one glass. Different discharge modes are selected by varying the impedance matching between the rf amplifier and the plasma. Hexagonal nuts placed on either end of the interstitial space between the plates create a potential well which can confine dust particles. Due to the relatively small spacing between plates, dust particles form vertical "molecules" of two particles bound together by the ion wake force. Results for systems of interacting molecules will be presented.. [Preview Abstract] |
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B1.00032: Quantum Optics {\&} Optical Engine Dyah-Adhi Wulandari-Bimo-Hari-Prayitno,Ir These were to concludes subject to Alejandro Gonzalez-Tudeja {\&} Diego Porras:\textbf{''Mesoscopic entanglement induced by spontaneous emissions in Solid-state quantum optics'' }\underline {PhysRevLett, }110(forgotten year), 080502. Refers to ``Optical Engines for Light Energy Detection'' \underline {www.physicstoday.org} , June 2012, h 60- denotes NewPort Corp's OptoFlash is a miniature multichannel spectrometer engine that detects light energy at multiple wavelength. According to NewPort, the demultiplexing optical engine is easy to customize with as many as 10 wavelength channels. It measure 51 x 16 x 25 mm {\&} weighs 30 g. Involves the CFD/ComputationalFluidDynamics and HCCI/HomogeneousChargeCompression Ignition, ever defined whereas ``ignition model engine'' popularly known as a model device diesel engine-Martin Frackowiak:\textbf{''Modelling {\&} Diagnostic Study of Flow in an Optical Engine with Negative Valve overlapping for HCCI'', }dissertation, ( 2009 ). [Preview Abstract] |
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B1.00033: Initial Debt per capita to more Advanced Solutions e.g. to Realms of State-owned Enterprises' Assets/Infrastructures Nitia ANISSA Comprises ``converge'' notions of [Petersen, et.al- 2010 ] ever retrieved from Georg Richard Newkome,2003:''Mathematics {\&} Art CONVERGE in the form of fractal that also abound in nature'' still just relativization of ``initial Debt per capita d(t)''. Further, refers to Habilation thesis from Dr. Rudi Schaefer:''Econophysics:Quantitative Studies of Equity {\&} Credit Market'', 2012 comprehend whereas it was more advanced to handles the INDONESIAN Foreign debt firstly in the realms of total State-owned Enterprises's Assets values of Rp. 4, 577 Trillion overwhelms November 2015 External Debt of the Government of INDONESIA as large as Rp. 4,243 Trillion whose US {\$} 304, 593 Billion amount coincides with US patent 4.304,593 from Arnulf J. Maeland, Dec 8, 1981. [Preview Abstract] |
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B1.00034: Quantum Causality Threshold Florentin Smarandache Considering two entangled particles and study all the possibilities: when both are immobile, or one of them is immobile, or both are moving in different directions, or one of them is moving in a different direction. Then we study the causality between them and the paradoxes, which are generated. We define the Causality Threshold of a particle A with respect to another particle B. The Quantum Causality Threshold of the particle A with respect to the particle B, to be the space-time when neither A nor B is a cause for the other on the B space-time axis. To change the causality of a particle A with respect to another particle B one has to pass through non-causality, i.e. one has to pass through their threshold. [Preview Abstract] |
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B1.00035: Mesoscopic Modelling In Organic Spintronics Rayyan-Ismail HANIF Mesoscopic modeling of complex systems involve thermodynamic nonequilibrium of discrete scaling of ntropy reduction $+$fluctuation, nonlinear dynamics {\&} complexity of self-organized spatio-temporal structure [Zhonghuai Hou: \textbf{``Nonlinear Dynamics {\&} Nonequilibrium Thermodynamics in Mesoscopic chemical Systems'' ].} ``Electron exchange {\&} electron- or photo-triggered electron exchange which are 2 central topic in related fields of molecular magnetism {\&} molecular spintronics through control of an external (optical, redox and/or magnetic ) properties in the use of several physics(spectrophysics, magnetic, electrochemical and/or photochemical)''-Maria Castellano SANZ, Dissertation, 2013. Obeys analytical studies of common mechanism of previously named ``spinterface'' have been forecasted through ``mesoscopic physics of electrons {\&} photons'' from E. Ackermans {\&} Gilles Montambaux of e.g.the ability to control spin polarization[WJM Naber, Sali Faez {\&} WG van der Wiel: \textbf{``Organic Spintronics'' }, arXiv:cond-mat/0703455v1[cond-mat.mes.hall], March 19, 2007 [Preview Abstract] |
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B1.00036: Degree of Dependence and Independence of Neutrosophic Logic Components Applied in Physics Florentin Smarandache Neutrosophic Logic is a general framework for unification of many existing logics, and its components T (truth), I (indeterminacy), F (falsehood) are standard or non-standard real subsets of ]$^{\mathrm{-}}$0, 1$^{\mathrm{+}}$[ with not necessarily any connection between them. For single valued neutrosophic logic, the sum of the components (T$+$I$+$F) is: 0 $\le $ T$+$I$+$F $\le $ 3 when all three components are independent; 0 $\le $ T$+$I$+$F $\le $ 2 when two components are dependent, while the third one is independent from them; 0 $\le $ T$+$I$+$F $\le $ 1 when all three components are dependent. When three or two of the components T, I, F are independent, one leaves room for incomplete information (sum \textless 1), paraconsistent and contradictory information (sum \textgreater 1), or complete information (sum $=$ 1).~ If all three components T, I, F are dependent, then similarly one leaves room for incomplete information (sum \textless 1), or complete information (sum $=$ 1).~ The dependent components are tied together. Three sources that provide information on T, I, and F respectively are independent if they do not communicate with each other and to not influence each other. The sum of two components x and y in general is: 0 $\le $ x$+$y $\le $ 2 -- d\textdegree (x, y), where d\textdegree (x, y) is the \textit{degree of dependence} between x and y. Therefore 2 -- d\textdegree (x, y) is the \textit{degree of independence} between x and y. But max\textbraceleft T$+$I$+$F\textbraceright may also get any value in [1, 3]. For example, suppose that T and F are 30{\%} dependent and 70{\%} independent (hence T$+$F $\le $ 2-0.3 $=$ 1.7), while I and F are 60{\%} dependent and 40{\%} dependent (hence I$+$F $\le $ 2-0.6 $=$ 1.4). Then max\textbraceleft T$+$I$+$F\textbraceright $=$ 2.4 and occurs for T $=$ 1, I $=$ 0.7, F $=$ 0.7. p.). [Preview Abstract] |
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B1.00037: Heavy Quantum, Nominally Identifies of Multifractal Neutrino Permata-SARI HARAHAP,ST ``For the discovery of neutrino oscillations which shows whereas neutrino have mass'' as one reason for 2015 NOBEL Prize in Physics awarded, `flare gas' to Paul A. Conlon:''Fields, Fractals and Flares..'', 2009 depict fractal relations, ranging from DNA knots to solar neutrino flux signals. Especially to mtDNA comprises fusion {\&} fission mechanism, ``fractal characters showen in Fig 1.7 through fluorapatite in gelatin-based bio-nanocomposite''- Eduardo Ruiz-Hitzky, et.al:''an Introduction to Bio-nanohybrid Materials''. In accordances to Wieslan M. Macek:''Fractals {\&} Multifractals'' and Tamas Tel: ``Fractal, Multifractals {\&} Thermodynamics'', 1988 herewith succeed to retrieves RP di Sisto,et.al: Physica A, 265 ( 1999 ), h 591:''solar neutrino puzzle based on Tsallis thermostatistics ..'' to ``fractal-like relevant phase space [ibid, 590 ], proposes ``multifractal neutrino'' as nominally identifies as well as ``meson'' for Hideki Yukawa's heavy quantum. [Preview Abstract] |
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B1.00038: Molecular Control of Metall-Supramolecular to K-Thoery Ratna-Permata SARI-HARAHAP,ST For ``Advances in this field have shown that the supra-molecular approach is a valuable tool for the design of new DNA recognition agent'' in Sukraj Kaur Banwait:'' Metallo-supramolecular Complexes {\&} their interactions with Biomolecules {\&} Cells'', Dissertation, 2009 those were provided ``Algebres de Clifford et K-theories'' through anthropologist Clifford GEERTZ ``as seen by Wigner and as seen by mathematician'' coinciding technicality to molecular recognition. Devotes from the WYSS Institute of Bioinspired Engineeering/''bio-Inspired computing'', for ``many organism are capable of synthetising organic/inorganic composites for protective or support purposes such as bones, shells {\&} teeth. They exert remarkable level of molecular control on particle size, structure, morphology, aggregation {\&} crystallographic orientation''- Xunpei Liu {\&} Surya K Mallapragada:''Bioinspired synthesis of organic/inorganic Nanocomposite Materials mediated by Biomolecules'' retrieved Eric M Friedlander:'' an Introduction to K-theory'', 2007 adopting bio-Organic fertilizer in e-Farm. [Preview Abstract] |
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