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Sample records for advanced atomic physics

  1. Advances in atomic physics

    PubMed Central

    El-Sherbini, Tharwat M.

    2013-01-01

    In this review article, important developments in the field of atomic physics are highlighted and linked to research works the author was involved in himself as a leader of the Cairo University – Atomic Physics Group. Starting from the late 1960s – when the author first engaged in research – an overview is provided of the milestones in the fascinating landscape of atomic physics. PMID:26425356

  2. Atomic physics at the advanced photon source

    SciTech Connect

    Berry, H.G.; Cowan, P.L.; Gemmell, D.S.

    1995-08-01

    Argonne`s 7-GeV synchrotron light source (APS) is expected to commence operations for research early in FY 1996. The Basic Energy Sciences Synchrotron Research Center (BESSRC) is likewise expected to start its research programs at that time. As members of the BESSRC CAT (Collaborative Access Team), we are preparing, together with atomic physicists from the University of Western Michigan, the University of Tennessee, and University of Notre Dame, to initiate a series of atomic physics experiments that exploit the unique capabilities of the APS, especially its high brilliance for photon energies extending from about 3 keV to more than 50 keV. Most of our early work will be conducted on an undulator beam line and we are thus concentrating on various aspects of that beam line and its associated experimental areas. Our group has undertaken responsibilities in such areas as hutch design, evaluation of undulator performance, user policy, interfacing and instrumentation, etc. Initial experiments will probably utilize existing apparatus. We are, however, planning to move rapidly to more sophisticated measurements involving, for example, ion-beam targets, simultaneous laser excitation, and the spectroscopy of emitted photons.

  3. Advances in atomic physics: Four decades of contribution of the Cairo University - Atomic Physics Group.

    PubMed

    El-Sherbini, Tharwat M

    2015-09-01

    In this review article, important developments in the field of atomic physics are highlighted and linked to research works the author was involved in himself as a leader of the Cairo University - Atomic Physics Group. Starting from the late 1960s - when the author first engaged in research - an overview is provided of the milestones in the fascinating landscape of atomic physics.

  4. Recent advances in Rydberg physics using alkaline-earth atoms

    NASA Astrophysics Data System (ADS)

    Dunning, F. B.; Killian, T. C.; Yoshida, S.; Burgdörfer, J.

    2016-06-01

    In this brief review, the opportunities that the alkaline-earth elements offer for studying new aspects of Rydberg physics are discussed. For example, the bosonic alkaline-earth isotopes have zero nuclear spin which eliminates many of the complexities present in alkali Rydberg atoms, permitting simpler and more direct comparison between theory and experiment. The presence of two valence electrons allows the production of singlet and triplet Rydberg states that can exhibit a variety of attractive or repulsive interactions. The availability of weak intercombination lines is advantageous for laser cooling and for applications such as Rydberg dressing. Excitation of one electron to a Rydberg state leaves behind an optically active core ion allowing, for high-L states, the optical imaging of Rydberg atoms and their (spatial) manipulation using light scattering. The second valence electron offers the possibility of engineering long-lived doubly excited states such as planetary atoms. Recent advances in both theory and experiment are highlighted together with a number of possible directions for the future.

  5. Research opportunities in atomic physics at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Schlachter, A. S.; Robinson, A. L.

    1989-09-01

    The Advanced Light Source (ALS) now under construction at the Lawrence Berkeley Laboratory is being planned as a national user facility for the production of high-brightness and partially coherent X-ray and ultraviolet synchrotron radiation. The ALS is based on a low-emittance electron storage ring optimized for operation at 1.5 GeV with insertion devices in 11 long straight sections and up to 48 bending-magnet ports. High-brightness photon beams from less than 10 eV to more than 1 keV will be produced by undulators, thereby providing many research opportunities in atomic and molecular physics and chemistry. Wigglers and bending magnets will provide high-flux broad-band radiation at energies to 10 keV.

  6. The Advanced Light Source: A new tool for research in atomic and molecular physics

    NASA Astrophysics Data System (ADS)

    Schlachter, F.; Robinson, A.

    1991-04-01

    The Advanced Light Source at the Lawrence Berkeley Laboratory will be the world's brightest synchrotron radiation source in the extreme ultraviolet and soft x-ray regions of the spectrum when it begins operation in 1993. It will be available as a national user facility to researchers in a broad range of disciplines, including materials science, atomic and molecular physics, chemistry, biology, imaging, and technology. The high brightness of the ALS will be particularly well suited to high-resolution studies of tenuous targets, such as excited atoms, ions, and clusters.

  7. Atomic physics

    SciTech Connect

    Livingston, A.E.; Kukla, K.; Cheng, S.

    1995-08-01

    In a collaboration with the Atomic Physics group at Argonne and the University of Toledo, the Atomic Physics group at the University of Notre Dame is measuring the fine structure transition energies in highly-charged lithium-like and helium-like ions using beam-foil spectroscopy. Precise measurements of 2s-2p transition energies in simple (few-electron) atomic systems provide stringent tests of several classes of current atomic- structure calculations. Analyses of measurements in helium-like Ar{sup 16+} have been completed, and the results submitted for publication. A current goal is to measure the 1s2s{sup 3}S{sub 1} - 1s2p{sup 3}P{sub 0} transition wavelength in helium-like Ni{sup 26+}. Measurements of the 1s2s{sup 2}S{sub 1/2} - 1s2p{sup 2}P{sub 1/2,3/2} transition wavelengths in lithium-like Kr{sup 33+} is planned. Wavelength and lifetime measurements in copper-like U{sup 63+} are also expected to be initiated. The group is also participating in measurements of forbidden transitions in helium-like ions. A measurement of the lifetime of the 1s2s{sup 3}S{sub 1} state in Kr{sup 34+} was published recently. In a collaboration including P. Mokler of GSI, Darmstadt, measurements have been made of the spectral distribution of the 2E1 decay continuum in helium-like Kr{sup 34+}. Initial results have been reported and further measurements are planned.

  8. Using an Advanced Computational Laboratory Experiment to Extend and Deepen Physical Chemistry Students' Understanding of Atomic Structure

    ERIC Educational Resources Information Center

    Hoffman, Gary G.

    2015-01-01

    A computational laboratory experiment is described, which involves the advanced study of an atomic system. The students use concepts and techniques typically covered in a physical chemistry course but extend those concepts and techniques to more complex situations. The students get a chance to explore the study of atomic states and perform…

  9. The advanced light source at Lawrence Berkeley laboratory: a new tool for research in atomic physics

    NASA Astrophysics Data System (ADS)

    Schlachter, Alfred S.; Robinson, Arthur L.

    1991-04-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high-quality bend-magnet ports. The short pulse width (30-50 ps) will be ideal for time-resolved measurements. Undulators will generate high-brightness partially coherent soft X-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV; this radiation is plane polarized. Wigglers and bend magnets will extend the spectrum by generating high fluxes of X-rays to photon energies above 10 keV. The ALS will have an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy), and in biology, such as X-ray microscopy with element-specific sensitivity; the high flux will allow measurements in atomic physics and chemistry to be made with tenuous gas-phase targets. Technological applications could include lithography and nano-fabrication.

  10. Recent advances in atomic modeling

    SciTech Connect

    Goldstein, W.H.

    1988-10-12

    Precision spectroscopy of solar plasmas has historically been the goad for advances in calculating the atomic physics and dynamics of highly ionized atoms. Recent efforts to understand the laboratory plasmas associated with magnetic and inertial confinement fusion, and with X-ray laser research, have played a similar role. Developments spurred by laboratory plasma research are applicable to the modeling of high-resolution spectra from both solar and cosmic X-ray sources, such as the photoionized plasmas associated with accretion disks. Three of these developments in large scale atomic modeling are reviewed: a new method for calculating large arrays of collisional excitation rates, a sum rule based method for extending collisional-radiative models and modeling the effects of autoionizing resonances, and a detailed level accounting calculation of resonant excitation rates in FeXVII. 21 refs., 5 figs., 2 tabs.

  11. The advanced light source — a new tool for research in atomic physics

    NASA Astrophysics Data System (ADS)

    Schlachter, A. S.

    1991-03-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory in Berkeley, California, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Undulators will generate high-brightness, partially coherent, plane polarized, soft x-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will generate high fluxes of x-rays to photon energies above 10 keV. The ALS will have an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms.

  12. The advanced light source: A new tool for research in atomic physics

    NASA Astrophysics Data System (ADS)

    Schlachter, A. S.

    1990-09-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory in Berkeley, California, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Undulators will generate high-brightness, partially coherent, plane polarized, soft-x-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will generate high fluxes of x-rays to photon energies above 10 keV. The ALS will have an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms.

  13. Contemporary Aspects of Atomic Physics

    ERIC Educational Resources Information Center

    Knott, R. G. A.

    1972-01-01

    The approach generally used in writing undergraduate textbooks on Atomic and Nuclear Physics presents this branch as historical in nature. Describes the concepts of astrophysics, plasma physics and spectroscopy as contemporary and intriguing for modern scientists. (PS)

  14. Atomic physics and quantum optics using superconducting circuits.

    PubMed

    You, J Q; Nori, Franco

    2011-06-29

    Superconducting circuits based on Josephson junctions exhibit macroscopic quantum coherence and can behave like artificial atoms. Recent technological advances have made it possible to implement atomic-physics and quantum-optics experiments on a chip using these artificial atoms. This Review presents a brief overview of the progress achieved so far in this rapidly advancing field. We not only discuss phenomena analogous to those in atomic physics and quantum optics with natural atoms, but also highlight those not occurring in natural atoms. In addition, we summarize several prospective directions in this emerging interdisciplinary field.

  15. Atomic physics processes in radial transport calculations

    SciTech Connect

    Hogan, J.T.

    1983-02-01

    These lectures were intended as preparation for detailed discussions of the role of atomic and molecular physics in confinement research at the 1982 NATO Advanced Study Institute. They begin with a description of the major approaches to magnetic confinement: tandem (ambipolar) mirrors with their associated auxiliary barriers, tokamaks, and stellarators. The leading alternatives, the ELMO Bumpy Torus and the reversed field pinch, are also treated. The evolution equations for particle, energy, and (where relevant) field diffusion are presented and discussed. This is the context for atomic and molecular processes relevant to confinement.

  16. Transition state in atomic physics

    NASA Astrophysics Data System (ADS)

    Jaffé, Charles; Farrelly, David; Uzer, T.

    1999-11-01

    The transition state is fundamental to modern theories of reaction dynamics: essentially, the transition state is a structure in phase space that all reactive trajectories must cross. While transition-state theory (TST) has been used mainly in chemical physics, it is possible to apply the theory to considerable advantage in any collision problem that involves some form of reaction. Of special interest are systems in which chaotic scattering or half-scattering occurs such as the ionization of Rydberg atoms in external fields. In this paper the ionization dynamics of a hydrogen atom in crossed electric and magnetic fields are shown to possess a transition state: We compute the periodic orbit dividing surface (PODS) which is found not to be a dividing surface when projected into configuration space. Although the possibility of a PODS occurring in phase space rather than configuration space has been recognized before, to our knowledge this is the first actual example: its origin is traced directly to the presence of velocity-dependent terms in the Hamiltonian. Our findings establish TST as the method of choice for understanding ionization of Rydberg atoms in the presence of velocity-dependent forces. To demonstrate this TST is used to (i) uncover a multiple-scattering mechanism for ionization and (ii) compute ionization rates. In the process we also develop a method of computing surfaces of section that uses periodic orbits to define the surface, and examine the fractal nature of the dynamics.

  17. Many-body physics using cold atoms

    NASA Astrophysics Data System (ADS)

    Sundar, Bhuvanesh

    Advances in experiments on dilute ultracold atomic gases have given us access to highly tunable quantum systems. In particular, there have been substantial improvements in achieving different kinds of interaction between atoms. As a result, utracold atomic gases oer an ideal platform to simulate many-body phenomena in condensed matter physics, and engineer other novel phenomena that are a result of the exotic interactions produced between atoms. In this dissertation, I present a series of studies that explore the physics of dilute ultracold atomic gases in different settings. In each setting, I explore a different form of the inter-particle interaction. Motivated by experiments which induce artificial spin-orbit coupling for cold fermions, I explore this system in my first project. In this project, I propose a method to perform universal quantum computation using the excitations of interacting spin-orbit coupled fermions, in which effective p-wave interactions lead to the formation of a topological superfluid. Motivated by experiments which explore the physics of exotic interactions between atoms trapped inside optical cavities, I explore this system in a second project. I calculate the phase diagram of lattice bosons trapped in an optical cavity, where the cavity modes mediates effective global range checkerboard interactions between the atoms. I compare this phase diagram with one that was recently measured experimentally. In two other projects, I explore quantum simulation of condensed matter phenomena due to spin-dependent interactions between particles. I propose a method to produce tunable spin-dependent interactions between atoms, using an optical Feshbach resonance. In one project, I use these spin-dependent interactions in an ultracold Bose-Fermi system, and propose a method to produce the Kondo model. I propose an experiment to directly observe the Kondo effect in this system. In another project, I propose using lattice bosons with a large hyperfine spin

  18. Bringing Atoms into First-Year Physics.

    ERIC Educational Resources Information Center

    Chabay, Ruth W.; Sherwood, Bruce A.

    1999-01-01

    Argues that thermal physics should not be treated as a separate topic in introductory physics. Provides an example of a course that emphasizes physical modeling of the phenomenon in terms of the atomic nature of matter. (Author/CCM)

  19. Improving Advanced High School Physics

    NASA Astrophysics Data System (ADS)

    Spital, Robin David

    2003-04-01

    A National Research Council study committee recently commissioned a "Physics Panel" to evaluate and make recommendations for improving advanced physics education in American high schools [1]. The Physics Panel recommends the creation of a nationally standardized Newtonian Mechanics Unit that would form the foundation of all advanced physics programs. In a one-year program, the Panel recommends that advanced physics students study at most one other major area of physics, so that sufficient time is available to develop the deep conceptual understanding that is the primary goal of advanced study. The Panel emphasizes that final assessments must be improved to focus on depth of understanding, rather than technical problem-solving skill. The Physics Panel strongly endorses the inclusion of meaningful real-world experiences in advanced physics programs, but believes that traditional "cook-book" laboratory exercises are not worth the enormous amount of time and effort spent on them. The Physics Panel believes that the talent and preparation of teachers are the most important ingredients in effective physics instruction; it therefore calls for a concerted effort by all parts of the physics community to remedy the desperate shortage of highly qualified teachers. [1] Jerry P. Gollub and Robin Spital, "Advanced Physics in the High Schools", Physics Today, May 2002.

  20. Physics through the 1990s: Atomic, molecular and optical physics

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The volume presents a program of research initiatives in atomic, molecular, and optical physics. The current state of atomic, molecular, and optical physics in the US is examined with respect to demographics, education patterns, applications, and the US economy. Recommendations are made for each field, with discussions of their histories and the relevance of the research to government agencies. The section on atomic physics includes atomic theory, structure, and dynamics; accelerator-based atomic physics; and large facilities. The section on molecular physics includes spectroscopy, scattering theory and experiment, and the dynamics of chemical reactions. The section on optical physics discusses lasers, laser spectroscopy, and quantum optics and coherence. A section elucidates interfaces between the three fields and astrophysics, condensed matter physics, surface science, plasma physics, atmospheric physics, and nuclear physics. Another section shows applications of the three fields in ultra-precise measurements, fusion, national security, materials, medicine, and other topics.

  1. Advances in atomic oxygen simulation

    NASA Technical Reports Server (NTRS)

    Froechtenigt, Joseph F.; Bareiss, Lyle E.

    1990-01-01

    Atomic oxygen (AO) present in the atmosphere at orbital altitudes of 200 to 700 km has been shown to degrade various exposed materials on Shuttle flights. The relative velocity of the AO with the spacecraft, together with the AO density, combine to yield an environment consisting of a 5 eV beam energy with a flux of 10(exp 14) to 10(exp 15) oxygen atoms/sq cm/s. An AO ion beam apparatus that produces flux levels and energy similar to that encountered by spacecraft in low Earth orbit (LEO) has been in existence since 1987. Test data was obtained from the interaction of the AO ion beam with materials used in space applications (carbon, silver, kapton) and with several special coatings of interest deposited on various surfaces. The ultimate design goal of the AO beam simulation device is to produce neutral AO at sufficient flux levels to replicate on-orbit conditions. A newly acquired mass spectrometer with energy discrimination has allowed 5 eV neutral oxygen atoms to be separated and detected from the background of thermal oxygen atoms of approx 0.2 eV. Neutralization of the AO ion beam at 5 eV was shown at the Martin Marietta AO facility.

  2. Relativistic atomic physics at the SSC

    SciTech Connect

    1990-12-31

    This report discusses the following proposed work for relativistic atomic physics at the Superconducting Super Collider: Beam diagnostics; atomic physics research; staffing; education; budget information; statement concerning matching funds; description and justification of major items of equipment; statement of current and pending support; and assurance of compliance.

  3. Benchmarking Attosecond Physics with Atomic Hydrogen

    DTIC Science & Technology

    2015-05-25

    Final 3. DATES COVERED (From - To) 12 Mar 12 – 11 Mar 15 4. TITLE AND SUBTITLE Benchmarking attosecond physics with atomic hydrogen 5a...NOTES 14. ABSTRACT The research team obtained uniquely reliable reference data on atomic interactions with intense few-cycle laser pulses...AND SUBTITLE Benchmarking attosecond physics with atomic hydrogen 5a. CONTRACT NUMBER FA2386-12-1-4025 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER

  4. Many-Body Atomic Physics

    NASA Astrophysics Data System (ADS)

    Boyle, J. J.; Pindzola, M. S.

    1998-09-01

    Preface; Contributors; Introduction; Part I. Atomic Structure: 1. Development of atomic many-body theory Ingvar Lindgren; 2. Relativistic MBPT for highly charged ions W. R. Johnson; 3. Parity nonconservation in atoms S. A. Blundell, W. R. Johnson, and J. Sapirstein; Part II. Photoionization of Atoms: 4. Single photoionization processes J. J. Boyle, and M. D. Kutzner; 5. Photoionization dominated by double excitation T. N. Chang; 6. Direct double photoionization in atoms Z. W. Liu; 7. Photoelectron angular distributions Steven T. Manson; Part III. A. Atomic Scattering - General Considerations: 8. The many-body approach to electron-atom collisions M. Ya Amusia; 9. Theoretical aspects of electron impact ionization P. L. Altick; Part III. B. Atomic Scattering - Low-Order Applications: 10. Perturbation series methods D. H. Madison; 11. Target dependence of the triply differential cross section Cheng Pan and Anthony F. Starace; 12. Overview of Thomas processes for fast mass transfer J. H. McGuire, Jack C. Straton and T. Ishihara; Part III. C. Atomic Scattering - All-Order Applications: 13. R-matrix Theory: Some Recent Applications Philip G. Burke: 14. Electron scattering: application of Dirac R-matrix theory Wasantha Wijesundera, Ian Grant and Patrick Norrington; 15. Close coupling and distorted-wave theory D. C. Griffin and M. S. Pindzola; Appendix: Units and notation; References; Index.

  5. Many-Body Atomic Physics

    NASA Astrophysics Data System (ADS)

    Boyle, J. J.; Pindzola, M. S.

    2005-11-01

    Preface; Contributors; Introduction; Part I. Atomic Structure: 1. Development of atomic many-body theory Ingvar Lindgren; 2. Relativistic MBPT for highly charged ions W. R. Johnson; 3. Parity nonconservation in atoms S. A. Blundell, W. R. Johnson, and J. Sapirstein; Part II. Photoionization of Atoms: 4. Single photoionization processes J. J. Boyle, and M. D. Kutzner; 5. Photoionization dominated by double excitation T. N. Chang; 6. Direct double photoionization in atoms Z. W. Liu; 7. Photoelectron angular distributions Steven T. Manson; Part III. A. Atomic Scattering - General Considerations: 8. The many-body approach to electron-atom collisions M. Ya Amusia; 9. Theoretical aspects of electron impact ionization P. L. Altick; Part III. B. Atomic Scattering - Low-Order Applications: 10. Perturbation series methods D. H. Madison; 11. Target dependence of the triply differential cross section Cheng Pan and Anthony F. Starace; 12. Overview of Thomas processes for fast mass transfer J. H. McGuire, Jack C. Straton and T. Ishihara; Part III. C. Atomic Scattering - All-Order Applications: 13. R-matrix Theory: Some Recent Applications Philip G. Burke: 14. Electron scattering: application of Dirac R-matrix theory Wasantha Wijesundera, Ian Grant and Patrick Norrington; 15. Close coupling and distorted-wave theory D. C. Griffin and M. S. Pindzola; Appendix: Units and notation; References; Index.

  6. Classical approach in atomic physics

    NASA Astrophysics Data System (ADS)

    Solov'ev, E. A.

    2011-12-01

    The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincaré section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormgroup symmetry, criterion of accuracy and so on are reviewed as well.

  7. Atomic and Molecular Physics Program

    DTIC Science & Technology

    2013-03-05

    DESCRIPTION OF PORTFOLIO: Understanding interactions between atoms, molecules, ions, and radiation. SUB-AREAS IN PORTFOLIO: • Cold Quantum ...Gases − Strongly-interacting quantum gases − Ultracold molecules − New phases of matter − Non-equilibrium quantum dynamics • Quantum Information...Science (QIS) − Quantum simulation − Quantum communication − Quantum metrology, sensing, and imaging − Cavity optomechanics 3 DISTRIBUTION STATEMENT

  8. The atomic hypothesis: physical consequences

    NASA Astrophysics Data System (ADS)

    Rivas, Martín

    2008-08-01

    The hypothesis that matter is made of some ultimate and indivisible objects, together with the restricted relativity principle, establishes a constraint on the kind of variables we are allowed to use for the variational description of elementary particles. We consider that the atomic hypothesis not only states the indivisibility of elementary particles, but also that these ultimate objects, if not annihilated, cannot be modified by any interaction so that all allowed states of an elementary particle are only kinematical modifications of any one of them. Therefore, an elementary particle cannot have excited states. In this way, the kinematical group of spacetime symmetries not only defines the symmetries of the system, but also the variables in terms of which the mathematical description of the elementary particles can be expressed in either the classical or the quantum mechanical description. When considering the interaction of two Dirac particles, the atomic hypothesis restricts the interaction Lagrangian to a kind of minimal coupling interaction.

  9. Physical Limits on Atomic Resolution

    NASA Astrophysics Data System (ADS)

    van Dyck, D.; van Aert, S.; den Dekker, A. J.

    2004-02-01

    It is shown that the ultimate resolution is not limited by the bandwidth of the microscope but by the bandwidth (i.e., the scattering power) of the object. In the case of a crystal oriented along a zone axis, the scattering is enhanced by the channeling of the electrons. However, if the object is aperiodic along the beam direction, the bandwidth is much more reduced. A particular challenge are the amorphous objects. For amorphous materials, the natural bandwidth is that of the single atom and of the order of 1 [Angstrom capital A, ring][minus sign]1, which can be reached with the present generation of medium voltage microscopes without aberration correctors. A clear distinction is made between resolving a structure and refining, that is, between resolution and precision. In the case of an amorphous structure, the natural bandwidth also puts a limit on the number of atom coordinates that can be refined quantitatively. As a consequence, amorphous structures cannot be determined from one projection, but only by using atomic resolution tomography. Finally a theory of experiment design is presented that can be used to predict the optimal experimental setting or the best instrumental improvement. Using this approach it is suggested that the study of amorphous objects should be done at low accelerating voltage with correction of both spherical and chromatic aberration.

  10. Preface: Advances in solar physics

    NASA Astrophysics Data System (ADS)

    Georgoulis, Manolis K.; Nakariakov, Valery M.

    2015-12-01

    The idea for this special issue of Advances in Space Research (ASR) was formulated during the 14th European Solar Physics Meeting (ESPM-14) that took place in Dublin, Ireland in September 2014. Since ASR does not publish conference proceedings, it was decided to extend a general call to the international solar-physics community for manuscripts pertinent to the following thematic areas: New and upcoming heliospheric observational and data assimilation facilities.

  11. The Atomic and Nuclear Physics of Atomic EDMs

    NASA Astrophysics Data System (ADS)

    Chupp, Timothy

    2016-09-01

    Atomic Electric-Dipole-Moment (EDM) measurements employ low-energy atomic and precision-measurement techniques to measure the effects of elementary particle forces that affect the distribution of charge and mass in the nucleus, which is probed by the atomic electrons. Experiments and their interpretation strongly overlap atomic and nuclear physics in the experimental and theoretical problems presented. On the experimental side, the atomic EDM couples to electric fields while the magnetic dipole moment couples to magnetic fields requiring exquisite control and characerization of the magnetic fields. Measuring the tiny frequency shifts requires clock-comparisons and a large signal-to-noise ratio for frequency resolution much smaller than the linewidths, which are lmitied by observation times. To address the experimental challenges, I will discuss systematic effects related to magnetic fields and techniques of magnetometry and co-magntometery as well as optical pumping and related techniques that enhance signal-to-noise. I will also address the interpretation of atomic EDMs in terms of a set of low-energy parameters that relate to effective-field-theory coefficients, and I will empshaize the need for improved calculations from both atomic-theory and nuclear theory.

  12. Recent advances in medical physics.

    PubMed

    Kalender, Willi A; Quick, Harald H

    2011-03-01

    Some of the major interests in medical physics over the last few years have concerned the technical advances in Computed Tomography and high field Magnetic Resonance Imaging. This review discusses the introduction of Dual Source CT and explains how it can not only offer faster data acquisition but also operate with lower radiation doses. This provides enormous benefits for all patients, but for cardiac and pediatric examinations in particular. The advances in MRI at 7 T esla are also impressive, with better signal to noise; cardiac and musculoskeletal applications are discussed; technical improvements are work-in-progress for other applications.

  13. Advanced Electron Microscopy in Materials Physics

    SciTech Connect

    Zhu, Y.; Jarausch, K.

    2009-06-01

    Aberration correction has opened a new frontier in electron microscopy by overcoming the limitations of conventional round lenses, providing sub-angstrom-sized probes and extending information limits. The imaging and analytical performance of these corrector-equipped microscopes affords an unprecedented opportunity to study structure-property relationships of matter at the atomic scale. This new generation of microscopes is able to retrieve high-quality structural information comparable to neutron and synchrotron x-ray experiments, but with local atomic resolution. These advances in instrumentation are accelerating the research and development of various functional materials ranging from those for energy generation, conversion, transportation and storage to those for catalysis and nano-device applications. The dramatic improvements in electron-beam illumination and detection also present a host of new challenges for the interpretation and optimization of experiments. During 7-9 November 2007, a workshop, entitled 'Aberration Corrected Electron Microscopy in Material Physics', was convened at the Center for Functional Nanomaterials, Brookhaven National Laboratories (BNL) to address these opportunities and challenges. The workshop was co-sponsored by Hitachi High Technologies, a leader in electron microscopy instrumentation, and BNL's Institute of Advanced Electron Microscopy, a leader in materials physics research using electron microscopy. The workshop featured presentations by internationally prominent scientists working at the frontiers of electron microscopy, both on developing instrumentation and applying it in materials physics. The meeting, structured to stimulate scientific exchanges and explore new capabilities, brought together {approx}100 people from over 10 countries. This special issue complies many of the advances in instrument performance and materials physics reported by the invited speakers and attendees at the workshop.

  14. 3He: cosmological and atomic physics experiments.

    PubMed

    Bunkov, Yuriy M

    2008-08-28

    Because the superfluid 3He order parameter exhibits many similarities with that of our Universe, the superfluid condensate may be considered as a quantum vacuum that carries various types of quasiparticles and topological defects. The condensate thus provides a test system for the experimental investigation of many general physics problems in cosmology, atomic or nuclear physics that are otherwise difficult or even impossible to investigate experimentally.

  15. Atomic and molecular physics at LURE

    SciTech Connect

    Morin, P. |

    1994-08-01

    A short overview of the present research activity at LURE is given, in the field of atomic and molecular physics. Three selected examples are discussed in more detail and the {open_quotes}SOLEIL{close_quotes} project of a new French synchrotron facility is presented.

  16. Advanced Computation in Plasma Physics

    NASA Astrophysics Data System (ADS)

    Tang, William

    2001-10-01

    Scientific simulation in tandem with theory and experiment is an essential tool for understanding complex plasma behavior. This talk will review recent progress and future directions for advanced simulations in magnetically-confined plasmas with illustrative examples chosen from areas such as microturbulence, magnetohydrodynamics, magnetic reconnection, and others. Significant recent progress has been made in both particle and fluid simulations of fine-scale turbulence and large-scale dynamics, giving increasingly good agreement between experimental observations and computational modeling. This was made possible by innovative advances in analytic and computational methods for developing reduced descriptions of physics phenomena spanning widely disparate temporal and spatial scales together with access to powerful new computational resources. In particular, the fusion energy science community has made excellent progress in developing advanced codes for which computer run-time and problem size scale well with the number of processors on massively parallel machines (MPP's). A good example is the effective usage of the full power of multi-teraflop MPP's to produce 3-dimensional, general geometry, nonlinear particle simulations which have accelerated progress in understanding the nature of turbulence self-regulation by zonal flows. It should be emphasized that these calculations, which typically utilized billions of particles for tens of thousands time-steps, would not have been possible without access to powerful present generation MPP computers and the associated diagnostic and visualization capabilities. In general, results from advanced simulations provide great encouragement for being able to include increasingly realistic dynamics to enable deeper physics insights into plasmas in both natural and laboratory environments. The associated scientific excitement should serve to stimulate improved cross-cutting collaborations with other fields and also to help attract

  17. Advanced computations in plasma physics

    NASA Astrophysics Data System (ADS)

    Tang, W. M.

    2002-05-01

    Scientific simulation in tandem with theory and experiment is an essential tool for understanding complex plasma behavior. In this paper we review recent progress and future directions for advanced simulations in magnetically confined plasmas with illustrative examples chosen from magnetic confinement research areas such as microturbulence, magnetohydrodynamics, magnetic reconnection, and others. Significant recent progress has been made in both particle and fluid simulations of fine-scale turbulence and large-scale dynamics, giving increasingly good agreement between experimental observations and computational modeling. This was made possible by innovative advances in analytic and computational methods for developing reduced descriptions of physics phenomena spanning widely disparate temporal and spatial scales together with access to powerful new computational resources. In particular, the fusion energy science community has made excellent progress in developing advanced codes for which computer run-time and problem size scale well with the number of processors on massively parallel machines (MPP's). A good example is the effective usage of the full power of multi-teraflop (multi-trillion floating point computations per second) MPP's to produce three-dimensional, general geometry, nonlinear particle simulations which have accelerated progress in understanding the nature of turbulence self-regulation by zonal flows. It should be emphasized that these calculations, which typically utilized billions of particles for thousands of time-steps, would not have been possible without access to powerful present generation MPP computers and the associated diagnostic and visualization capabilities. In general, results from advanced simulations provide great encouragement for being able to include increasingly realistic dynamics to enable deeper physics insights into plasmas in both natural and laboratory environments. The associated scientific excitement should serve to

  18. Cold Atoms, Statistical Physics and Quantum Simulations

    DTIC Science & Technology

    2010-07-22

    to be the development of robust theoretical techniques for the simulations of ultra-cold Bose gases and other quantum phenomena, such theoretical...finite-temperature effects in atom-chip interferometry of Bose -Einstein condensates, R. G. Scott, et al., Physical Review A, 063624 (2009). A copy of...March 2009. Mr Hodder was supported through a University of Otago Scholarship. He initially developed a simple single-site Hubbard model, which can be

  19. Handbook explaining the fundamentals of nuclear and atomic physics

    NASA Technical Reports Server (NTRS)

    Hanlen, D. F.; Morse, W. J.

    1969-01-01

    Indoctrination document presents nuclear, reactor, and atomic physics in an easy, straightforward manner. The entire subject of nuclear physics including atomic structure ionization, isotopes, radioactivity, and reactor dynamics is discussed.

  20. Atomic physics with vapor-cell clocks

    NASA Astrophysics Data System (ADS)

    McGuyer, Bart Hunter

    The most widely used atomic frequency standards (or clocks) are based on the microwave resonant frequencies of optically pumped vapors of alkali-metal atoms in glass cells filled with buffer gas. These vapor-cell clocks are secondary, not primary frequency standards mainly because of the light and pressure shifts, which alter the resonant frequencies of the alkali-metal atoms. This dissertation presents studies of atomic physics important to vapor-cell clocks and, in particular, their accuracy. First, we report a simple method to suppress the light shift in optical pumping systems. This method uses only frequency modulation of a radio frequency or microwave source, which excites an atomic resonance, to simultaneously lock the source frequency to the atomic resonance and lock the pumping light frequency to suppress the light shift. This technique can be applied to many optical pumping systems that experience light shifts. It is especially useful for atomic clocks because it improves the long-term performance, reduces the influence of a pumping laser, and requires less equipment than previous methods. Next, we present three studies of the pressure shift, starting with an estimation of the hyperfine-shift potential that is responsible for most of the pressure shift. We then show that the microwave resonant frequencies of ground-state Rb and Cs atoms in Xe buffer gas have a relatively large nonlinear dependence on the Xe pressure, presumably because of short-lived RbXe and CsXe van der Waals molecules. The Xe data show striking discrepancies with the previous theory for nonlinear shifts, most of which is eliminated by accounting for the spin-rotation interaction in addition to the hyperfine-shift interaction in the molecules. To the limit of our experimental accuracy, the shifts of Rb and Cs in He, Ne, and N2 were linear with pressure. We then consider the prospects for suppressing the pressure shift with buffer-gas mixtures and feedback. Finally, we report an

  1. Physics of Compact Advanced Stellarators

    SciTech Connect

    M.C. Zarnstorff; L.A. Berry; A. Brooks; E. Fredrickson; G.-Y. Fu; S. Hirshman; S. Hudson; L.-P. Ku; E. Lazarus; D. Mikkelsen; D. Monticello; G.H. Neilson; N. Pomphrey; A. Reiman; D. Spong; D. Strickler; A. Boozer; W.A. Cooper; R. Goldston; R. Hatcher; M. Isaev; C. Kessel; J. Lewandowski; J. Lyon; P. Merkel; H. Mynick; B.E. Nelson; C. Nuehrenberg; M. Redi; W. Reiersen; P. Rutherford; R. Sanchez; J. Schmidt; R.B. White

    2001-08-14

    Compact optimized stellarators offer novel solutions for confining high-beta plasmas and developing magnetic confinement fusion. The 3-D plasma shape can be designed to enhance the MHD stability without feedback or nearby conducting structures and provide drift-orbit confinement similar to tokamaks. These configurations offer the possibility of combining the steady-state low-recirculating power, external control, and disruption resilience of previous stellarators with the low-aspect ratio, high beta-limit, and good confinement of advanced tokamaks. Quasi-axisymmetric equilibria have been developed for the proposed National Compact Stellarator Experiment (NCSX) with average aspect ratio 4-4.4 and average elongation of approximately 1.8. Even with bootstrap-current consistent profiles, they are passively stable to the ballooning, kink, vertical, Mercier, and neoclassical-tearing modes for beta > 4%, without the need for external feedback or conducting walls. The bootstrap current generates only 1/4 of the magnetic rotational transform at beta = 4% (the rest is from the coils), thus the equilibrium is much less nonlinear and is more controllable than similar advanced tokamaks. The enhanced stability is a result of ''reversed'' global shear, the spatial distribution of local shear, and the large fraction of externally generated transform. Transport simulations show adequate fast-ion confinement and thermal neoclassical transport similar to equivalent tokamaks. Modular coils have been designed which reproduce the physics properties, provide good flux surfaces, and allow flexible variation of the plasma shape to control the predicted MHD stability and transport properties.

  2. Advanced atom chips with two metal layers.

    SciTech Connect

    Stevens, James E.; Blain, Matthew Glenn; Benito, Francisco M.; Biedermann, Grant

    2010-12-01

    A design concept, device layout, and monolithic microfabrication processing sequence have been developed for a dual-metal layer atom chip for next-generation positional control of ultracold ensembles of trapped atoms. Atom chips are intriguing systems for precision metrology and quantum information that use ultracold atoms on microfabricated chips. Using magnetic fields generated by current carrying wires, atoms are confined via the Zeeman effect and controllably positioned near optical resonators. Current state-of-the-art atom chips are single-layer or hybrid-integrated multilayer devices with limited flexibility and repeatability. An attractive feature of multi-level metallization is the ability to construct more complicated conductor patterns and thereby realize the complex magnetic potentials necessary for the more precise spatial and temporal control of atoms that is required. Here, we have designed a true, monolithically integrated, planarized, multi-metal-layer atom chip for demonstrating crossed-wire conductor patterns that trap and controllably transport atoms across the chip surface to targets of interest.

  3. Advanced atomic force microscopy: Development and application

    NASA Astrophysics Data System (ADS)

    Walters, Deron A.

    Over the decade since atomic force microscopy (AFM) was invented, development of new microscopes has been closely intertwined with application of AFM to problems of interest in physics, chemistry, biology, and engineering. New techniques such as tapping mode AFM move quickly in our lab from the designer's bench to the user's table-since this is often the same piece of furniture. In return, designers get ample feedback as to what problems are limiting current instruments, and thus need most urgent attention. Tip sharpness and characterization are such a problem. Chapter 1 describes an AFM designed to operate in a scanning electron microscope, whose electron beam is used to deposit sharp carbonaceous tips. These tips can be tested and used in situ. Another limitation is addressed in Chapter 2: the difficulty of extracting more than just topographic information from a sample. A combined AFM/confocal optical microscope was built to provide simultaneous, independent images of the topography and fluorescence of a sample. In combination with staining or antibody labelling, this could provide submicron information about the composition of a sample. Chapters 3 and 4 discuss two generations of small cantilevers developed for lower-noise, higher-speed AFM of biological samples. In Chapter 4, a 26 mum cantilever is used to image the process of calcite growth from solution at a rate of 1.6 sec/frame. Finally, Chapter 5 explores in detail a biophysics problem that motivates us to develop fast, quiet, and gentle microscopes; namely, the control of crystal growth in seashells by the action of soluble proteins on a growing calcite surface.

  4. Astronomy-inspired Atomic and Molecular Physics

    NASA Astrophysics Data System (ADS)

    Rau, A. R. P.

    2002-02-01

    Aimed at senior undergraduate and first-year graduate students in departments of physics and astronomy, this textbook gives a systematic treatment of atomic and molecular structure and spectra, together with the effect of weak and strong external electromagnetic fields. Topics chosen are those of interest in astronomy and indeed many were inspired by specific astronomical contexts. Examples include the negative ion of hydrogen and the effects of strong magnetic fields such as those occurring on certain white dwarfs and neutron stars. Adiabatic and non-adiabatic handling of electron correlations and application to processes such as dielectronic recombination are included. Astronomical examples are provided throughout as well as end-of-the chapter problems and exercises. Over seventy illustrative diagrams complete this unique and comprehensive volume. Link: http://www.wkap.nl/prod/b/1-4020-0467-2

  5. Recent Advances in Neutron Physics

    ERIC Educational Resources Information Center

    Feshbach, Herman; Sheldon, Eric

    1977-01-01

    Discusses new studies in neutron physics within the last decade, such as ultracold neutrons, neutron bottles, resonance behavior, subthreshold fission, doubly radiative capture, and neutron stars. (MLH)

  6. Atomic physics and non-equilibrium plasmas

    SciTech Connect

    Weisheit, J.C.

    1986-04-25

    Three lectures comprise the report. The lecture, Atomic Structure, is primarily theoretical and covers four topics: (1) Non-relativistic one-electron atom, (2) Relativistic one-electron atom, (3) Non-relativistic many-electron atom, and (4) Relativistic many-electron atom. The lecture, Radiative and Collisional Transitions, considers the problem of transitions between atomic states caused by interactions with radiation or other particles. The lecture, Ionization Balance: Spectral Line Shapes, discusses collisional and radiative transitions when ionization and recombination processes are included. 24 figs., 11 tabs.

  7. Advances in Atomic Gyroscopes: A View from Inertial Navigation Applications

    PubMed Central

    Fang, JianCheng; Qin, Jie

    2012-01-01

    With the rapid development of modern physics, atomic gyroscopes have been demonstrated in recent years. There are two types of atomic gyroscope. The Atomic Interferometer Gyroscope (AIG), which utilizes the atomic interferometer to sense rotation, is an ultra-high precision gyroscope; and the Atomic Spin Gyroscope (ASG), which utilizes atomic spin to sense rotation, features high precision, compact size and the possibility to make a chip-scale one. Recent developments in the atomic gyroscope field have created new ways to obtain high precision gyroscopes which were previously unavailable with mechanical or optical gyroscopes, but there are still lots of problems that need to be overcome to meet the requirements of inertial navigation systems. This paper reviews the basic principles of AIG and ASG, introduces the recent progress in this area, focusing on discussing their technical difficulties for inertial navigation applications, and suggests methods for developing high performance atomic gyroscopes in the near future. PMID:22778644

  8. Advances in atomic gyroscopes: a view from inertial navigation applications.

    PubMed

    Fang, JianCheng; Qin, Jie

    2012-01-01

    With the rapid development of modern physics, atomic gyroscopes have been demonstrated in recent years. There are two types of atomic gyroscope. The Atomic Interferometer Gyroscope (AIG), which utilizes the atomic interferometer to sense rotation, is an ultra-high precision gyroscope; and the Atomic Spin Gyroscope (ASG), which utilizes atomic spin to sense rotation, features high precision, compact size and the possibility to make a chip-scale one. Recent developments in the atomic gyroscope field have created new ways to obtain high precision gyroscopes which were previously unavailable with mechanical or optical gyroscopes, but there are still lots of problems that need to be overcome to meet the requirements of inertial navigation systems. This paper reviews the basic principles of AIG and ASG, introduces the recent progress in this area, focusing on discussing their technical difficulties for inertial navigation applications, and suggests methods for developing high performance atomic gyroscopes in the near future.

  9. Optical physics: Ultrashort light pulses shake atoms

    NASA Astrophysics Data System (ADS)

    Kim, Kyung Taec

    2016-02-01

    The response of electrons in atoms to ultrashort optical light pulses has been probed by measuring the ultraviolet light emitted by the atoms. This reveals that a finite time delay occurs before the response. See Letter p.66

  10. Experiments in atomic and applied physics using synchrotron radiation

    SciTech Connect

    Jones, K.W.

    1987-01-01

    A diverse program in atomic and applied physics using x rays produced at the X-26 beam line at the Brookhaven National Synchrotron Light Source is in progress. The atomic physics program studies the properties of multiply-ionized atoms using the x rays for photo-excitation and ionization of neutral atoms and ion beams. The applied physics program builds on the techniques and results of the atomic physics work to develop new analytical techniques for elemental and chemical characterization of materials. The results are then used for a general experimental program in biomedical sciences, geo- and cosmochemistry, and materials sciences. The present status of the program is illustrated by describing selected experiments. Prospects for development of new experimental capabilities are discussed in terms of a heavy ion storage ring for atomic physics experiments and the feasibility of photoelectron microscopy for high spatial resolution analytical work. 21 refs., 11 figs., 2 tabs.

  11. Advancements in Solar Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Miramonti, Lino; Antonelli, Vito

    2013-03-01

    We review the results of solar neutrino physics, with particular attention to the data obtained and the analyses performed in the last decades, which were determinant to solve the solar neutrino problem (SNP), proving that neutrinos are massive and oscillating particles and contributing to refine the solar models. We also discuss the perspectives of the presently running experiments in this sector and of the ones planned for the near future and the impact they can have on elementary particle physics and astrophysics.

  12. Quantum dynamics in ultracold atomic physics

    NASA Astrophysics Data System (ADS)

    He, Qiong-Yi; Reid, Margaret D.; Opanchuk, Bogdan; Polkinghorne, Rodney; Rosales-Zárate, Laura E. C.; Drummond, Peter D.

    2012-02-01

    We review recent developments in the theory of quantum dynamics in ultracold atomic physics, including exact techniques and methods based on phase-space mappings that are applicable when the complexity becomes exponentially large. Phase-space representations include the truncated Wigner, positive- P and general Gaussian operator representations which can treat both bosons and fermions. These phase-space methods include both traditional approaches using a phase-space of classical dimension, and more recent methods that use a non-classical phase-space of increased dimensionality. Examples used include quantum Einstein-Podolsky-Rosen (EPR) entanglement of a four-mode BEC, time-reversal tests of dephasing in single-mode traps, BEC quantum collisions with up to 106 modes and 105 interacting particles, quantum interferometry in a multi-mode trap with nonlinear absorption, and the theory of quantum entropy in phase-space. We also treat the approach of variational optimization of the sampling error, giving an elementary example of a nonlinear oscillator.

  13. Probing non-Hermitian physics with flying atoms

    NASA Astrophysics Data System (ADS)

    Wen, Jianming; Xiao, Yanhong; Peng, Peng; Cao, Wanxia; Shen, Ce; Qu, Weizhi; Jiang, Liang

    2016-05-01

    Non-Hermtian optical systems with parity-time (PT) symmetry provide new means for light manipulation and control. To date, most of experimental demonstrations on PT symmetry rely on advanced nanotechnologies and sophisticated fabrication techniques to manmade solid-state materials. Here, we report the first experimental realization of optical anti-PT symmetry, a counterpart of conventional PT symmetry, in a warm atomic-vapor cell. By exploiting rapid coherence transport via flying atoms, we observe essential features of anti-PT symmetry with an unprecedented precision on phase-transition threshold. Moreover, our system allows nonlocal interference of two spatially-separated fields as well as anti-PT assisted four-wave mixing. Besides, another intriguing feature offered by the system is refractionless (or unit-refraction) light propagation. Our results thus represent a significant advance in non-Hermitian physics by bridging a firm connection with the AMO field, where novel phenomena and applications in quantum and nonlinear optics aided by (anti-)PT symmetry can be anticipated.

  14. Project Physics Text 5, Models of the Atom.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    Basic atomic theories are presented in this fifth unit of the Project Physics text for use by senior high students. Chemical basis of atomic models in the early years of the 18th Century is discussed n connection with Dalton's theory, atomic properties, and periodic tables. The discovery of electrons is described by using cathode rays, Millikan's…

  15. Advancing differential atom interferometry for space applications

    NASA Astrophysics Data System (ADS)

    Chiow, Sheng-Wey; Williams, Jason; Yu, Nan

    2016-05-01

    Atom interferometer (AI) based sensors exhibit precision and accuracy unattainable with classical sensors, thanks to the inherent stability of atomic properties. Dual atomic sensors operating in a differential mode further extend AI applicability beyond environmental disturbances. Extraction of the phase difference between dual AIs, however, typically introduces uncertainty and systematic in excess of that warranted by each AI's intrinsic noise characteristics, especially in practical applications and real time measurements. In this presentation, we report our efforts in developing practical schemes for reducing noises and enhancing sensitivities in the differential AI measurement implementations. We will describe an active phase extraction method that eliminates the noise overhead and demonstrates a performance boost of a gravity gradiometer by a factor of 3. We will also describe a new long-baseline approach for differential AI measurements in a laser ranging assisted AI configuration. The approach uses well-developed AIs for local measurements but leverage the mature schemes of space laser interferometry for LISA and GRACE. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a Contract with NASA.

  16. GENERAL VIEW, LOOKING NORTH, OF ATOMIC PHYSICS OBSERVATORY WHICH CONTAINS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW, LOOKING NORTH, OF ATOMIC PHYSICS OBSERVATORY WHICH CONTAINS THE WHITE DOME STRUCTURE. THE SHED-LIKE STRUCTURE TO THE LEFT IS THE SEARCH-LIGHT BUILDING. - Carnegie Institution of Washington, Department of Terrestrial Magnetism, Atomic Physics Observatory, 5241 Broad Branch Drive Northwest, Washington, District of Columbia, DC

  17. Physics in advanced GNVQ Science

    NASA Astrophysics Data System (ADS)

    Sang, D.

    1995-07-01

    GNVQ Science is a vocational qualification for students in England, with a demand equivalent to traditional GCE A-levels. This article looks at the approach adopted by GNVQ to physics, and discusses the way in which appropriate teaching resources have been developed by the Nuffield Science in Practice project.

  18. Advanced Physics Lab at TCU

    NASA Astrophysics Data System (ADS)

    Quarles, C. A.

    2009-04-01

    The one semester, one credit hour Modern Physics Lab is viewed as a transition between the structured Physics 1 and 2 labs and junior/senior research. The labs focus on a variety of experiments built around a multichannel analyzer, various alpha, beta and gamma ray detectors and weak radioactive sources. Experiments include radiation safety and detection with a Geiger counter and NaI detector, gamma ray spectroscopy with a germanium detector, beta spectrum, alpha energy loss, gamma ray absorption, Compton effect, nuclear and positron annihilation lifetime, speed of gamma rays. Other experiments include using the analog oscilloscope, x-ray diffraction of diamond and using an SEM/EDX. Error analysis is emphasized throughout. The semester ends with an individual project, often an extension of one of the earlier experiments, and students present their results as a paper and an APS style presentation to the department.

  19. Atomic Physics, Science (Experimental): 5318.42.

    ERIC Educational Resources Information Center

    Petit, Ralph E.

    Presented is the study of modern and classical concepts of the atom; the structure of the atom as a mass-energy relationship; practical uses of radioactivity; isotopes; and the strange particles. Performance objectives (16) are included as well as a detailed course outline. Experiments, demonstrations, projects and reports to enhance student…

  20. Advanced analysis methods in particle physics

    SciTech Connect

    Bhat, Pushpalatha C.; /Fermilab

    2010-10-01

    Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.

  1. Atomic physics experiments with stored cooled heavy ion beams

    SciTech Connect

    Datz, S.

    1986-01-01

    The wide ranging interest in the development of heavy ion synchrotrons with electron beam cooling is evident from the number of projects presently under way. Although much of the initial motivation for these rings stemmed from nuclear and particle physics, a considerable amount of atomic physics experimentation is planned. This paper surveys some of the new opportunities in atomic physics which may be made available with storage ring systems. 25 refs., 3 tabs.

  2. Atomic Structure Calculations from the Los Alamos Atomic Physics Codes

    DOE Data Explorer

    Cowan, R. D.

    The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

  3. Atomic physics: A milestone in quantum computing

    NASA Astrophysics Data System (ADS)

    Bartlett, Stephen D.

    2016-08-01

    Quantum computers require many quantum bits to perform complex calculations, but devices with more than a few bits are difficult to program. A device based on five atomic quantum bits shows a way forward. See Letter p.63

  4. Advanced Propulsion Physics Lab: Eagleworks Investigations

    NASA Technical Reports Server (NTRS)

    Scogin, Tyler

    2014-01-01

    Eagleworks Laboratory is an advanced propulsions physics laboratory with two primary investigations currently underway. The first is a Quantum Vacuum Plasma Thruster (QVPT or Q-thrusters), an advanced electric propulsion technology in the development and demonstration phase. The second investigation is in Warp Field Interferometry (WFI). This is an investigation of Dr. Harold "Sonny" White's theoretical physics models for warp field equations using optical experiments in the Electro Optical laboratory (EOL) at Johnson Space Center. These investigations are pursuing technology necessary to enable human exploration of the solar system and beyond.

  5. Strong interaction physics from hadronic atoms

    NASA Astrophysics Data System (ADS)

    Batty, C. J.; Friedman, E.; Gal, A.

    1997-08-01

    Hadronic atoms provide a unique laboratory for studying strong interactions and nuclear medium effects at zero kinetic energy. Previous results from analyses of strong-interaction data consisting of level shifts, widths and yields in π-, K -, p¯ and ∑ - atoms are reviewed. Recent results from fits to comprehensive sets of data in terms of density-dependent optical potentials that respect the low-density limit, where the interaction tends to the free hadron nucleon value, are discussed. The importance of using realistic nuclear density distributions is highlighted. The introduction of density dependence in most cases significantly improves the fit to the data and leads to some novel results. For K - atoms, a substantial attraction of order 200 MeV in nuclear matter is suggested, with interesting repercussions for K¯ condensation and the evolution of strangeness in high-density stars. For p¯ atoms it is found that a reasonable p-wave strength can be accommodated in the fitted optical potential, in agreement with the energy dependence observed for some low-energy p¯N reactions. For ∑ - atoms, the fitted potential becomes repulsive inside the nucleus, implying that Σ hyperons generally do not bind in nuclei in agreement with recent measurements. This repulsion significantly affects calculated masses of neutron stars.

  6. Atomic physics with highly charged ions

    SciTech Connect

    Richard, P.

    1991-08-01

    This report discusses: One electron outer shell processes in fast ion-atom collisions; role of electron-electron interaction in two-electron processes; multi-electron processes at low energy; multi-electron processes at high energy; inner shell processes; molecular fragmentation studies; theory; and, JRM laboratory operations.

  7. Project Physics Tests 5, Models of the Atom.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    Test items relating to Project Physics Unit 5 are presented in this booklet. Included are 70 multiple-choice and 23 problem-and-essay questions. Concepts of atomic model are examined on aspects of relativistic corrections, electron emission, photoelectric effects, Compton effect, quantum theories, electrolysis experiments, atomic number and mass,…

  8. ATOMIC PHYSICS, AN AUTOINSTRUCTIONAL PROGRAM, VOLUME 2, SUPPLEMENT.

    ERIC Educational Resources Information Center

    DETERLINE, WILLIAM A.; KLAUS, DAVID J.

    THE AUTOINSTRUCTIONAL MATERIALS IN THIS TEXT WERE PREPARED FOR USE IN AN EXPERIMENTAL STUDY, OFFERING SELF-TUTORING MATERIAL FOR LEARNING ATOMIC PHYSICS. THE TOPICS COVERED ARE (1) ISOTOPES AND MASS NUMBERS, (2) MEASURING ATOMIC MASS, (3) DISCOVERY OF THE NUCLEUS, (4) STRUCTURE OF THE NUCLEUS, (5) DISCOVERY OF THE NEUTRON, (6) NUCLEAR REACTIONS,…

  9. NASA GSFC Science Symposium on Atomic and Molecular Physics

    NASA Technical Reports Server (NTRS)

    Bhatia, Anand K. (Editor)

    2007-01-01

    This document is the proceedings of a conference on atomic and molecular physics in honor of the retirements of Dr. Aaron Temkin and Dr. Richard Drachman. The conference contained discussions on electron, positron, atomic, and positronium physics, as well as a discussion on muon catalyzed fusion. This proceedings document also contains photographs taken at the symposium, as well as speeches and a short biography made in tribute to the retirees.

  10. Physics challenges for advanced fuel cycle assessment

    SciTech Connect

    Giuseppe Palmiotti; Massimo Salvatores; Gerardo Aliberti

    2014-06-01

    Advanced fuel cycles and associated optimized reactor designs will require substantial improvements in key research area to meet new and more challenging requirements. The present paper reviews challenges and issues in the field of reactor and fuel cycle physics. Typical examples are discussed with, in some cases, original results.

  11. Advanced Fencing; Physical Education: 5551.54.

    ERIC Educational Resources Information Center

    McInerney, Marjorie

    GRADES OR AGES: Grades 8-12. SUBJECT MATTER: Strategy, tactics, principles, and fundamentals of advanced fencing skills. ORGANIZATION AND PHYSICAL APPEARANCE: The contents are divided into seven areas, which are Course Guidelines, Course Description and Broad Goal, Course of Study Behavioral Objectives, Course Content, Learning Activities and…

  12. Teacher's Handbook for Advanced Physical Science 2.

    ERIC Educational Resources Information Center

    Chaffee, Everett

    This handbook is an adjunct to the "Laboratory Manual for Advanced Physical Science 2," and is intended to assist teachers in organizing laboratory experiences. Information for each experiment includes (1) Introduction, (2) Scheduling, (3) Time required, (4) Materials needed , (5) Precautions, (6) Laboratory hints, (7) Sample data, and…

  13. Research in Dense Plasma Atomic Physics.

    DTIC Science & Technology

    1984-04-19

    attention on * the solution to the time-independent Schrodinger equation with a self- consistent charge density. For calculations of atomic properties the...interaction potential. Incorporating this potential, the bound and free electron distributions are found from the Schrodinger equation . Thus, given an...spherically symmetric. In Eq. (1), .b is the local density of bound electrons found from solving * the Schrodinger equation where the interaction

  14. Probing physical properties at the nanoscale using atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Ditzler, Lindsay Rachel

    Techniques that measure physical properties at the nanoscale with high sensitivity are significantly limited considering the number of new nanomaterials being developed. The development of atomic force microscopy (AFM) has lead to significant advancements in the ability to characterize physical properties of materials in all areas of science: chemistry, physics, engineering, and biology have made great scientific strides do to the versatility of the AFM. AFM is used for quantification of many physical properties such as morphology, electrical, mechanical, magnetic, electrochemical, binding interactions, and protein folding. This work examines the electrical and mechanical properties of materials applicable to the field of nano-electronics. As electronic devices are miniaturized the demand for materials with unique electrical properties, which can be developed and exploited, has increased. For example, discussed in this work, a derivative of tetrathiafulvalene, which exhibits a unique loss of conductivity upon compression of the self-assembled monolayer could be developed into a molecular switch. This work also compares tunable organic (tetraphenylethylene tetracarboxylic acid and bis(pyridine)s assemblies) and metal-organic (Silver-stilbizole coordination compounds) crystals which show high electrical conductivity. The electrical properties of these materials vary depending on their composition allowing for the development of compositionally tunable functional materials. Additional work was done to investigate the effects of molecular environment on redox active 11-ferroceneyl-1 undecanethiol (Fc) molecules. The redox process of mixed monolayers of Fc and decanethiol was measured using conductive probe atomic force microscopy and force spectroscopy. As the concentration of Fc increased large, variations in the force were observed. Using these variations the number of oxidized molecules in the monolayer was determined. AFM is additionally capable of investigating

  15. Proceedings of the workshop on opportunities for atomic physics using slow, highly-charged ions

    SciTech Connect

    Not Available

    1987-01-01

    The study of atomic physics with highly-charged ions is an area of intense activity at the present time because of a convergence of theoretical interest and advances in experimental techniques. The purpose of the Argonne ''Workshop on Opportunities for Atomic Physics Using Slow, Highly-Charged Ions'' was to bring together atomic, nuclear, and accelerator physicists in order to identify what new facilities would be most useful for the atomic physics community. The program included discussion of existing once-through machines, advanced ion sources, recoil ion techniques, ion traps, and cooler rings. One of the topics of the Workshop was to discuss possible improvement to the ANL Tandem-Linac facility (ATLAS) to enhance the capability for slowing down ions after they are stripped to a high-charge state (the Accel/Decel technique). Another topic was the opportunity for atomic physics provided by the ECR ion source which is being built for the Uranium Upgrade of ATLAS. 18 analytics were prepared for the individual papers in this volume.

  16. Atoms in Flight: The Remarkable Connections between Atomic and Hadronic Physics

    SciTech Connect

    Brodsky, Stanley J.; /SLAC

    2012-02-16

    Atomic physics and hadron physics are both based on Yang Mills gauge theory; in fact, quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics provide important insight into the theory of hadrons in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of light-front relativistic equations of motion which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The renormalization scale for the running coupling, which is unambiguously set in QED, leads to a method for setting the renormalization scale in QCD. The production of atoms in flight provides a method for computing the formation of hadrons at the amplitude level. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, and light-front quantization have equal utility for atomic physics, especially in the relativistic domain. I also present a new perspective for understanding the contributions to the cosmological constant from QED and QCD.

  17. Advances in Bichromatic Force Slowing of Atoms and Molecules

    NASA Astrophysics Data System (ADS)

    Chieda, M. A.; Eyler, E. E.

    2012-06-01

    The optical bichromatic force (BCF) holds promise as an efficient, simple, and compact means to slow atoms and molecules to MOT capture velocities.ootnotetextM. Cashen and H. Metcalf, JOSA B 20, 915 (2003).^,ootnotetextM. A. Chieda and E. E. Eyler, PRA 84, 063401 (2011). Metastable helium beams, with v˜1000 m/s, are especially worthwhile atomic candidates since they presently require Zeeman slowers with lengths of 2--3 m. We present a novel BCF decelerator in which the Doppler shifts are chirped to keep the force centered on the atoms as they slow. This is made possible by recent advances in high-power diode lasers and electronics, and avoids many of the problems of alternative designs using large detunings. Initial tests on He* atoms show encouraging results. Unlike atoms, direct laser slowing of molecules remains exceedingly difficult, although success with SrF has very recently been reported.ootnotetextJ. F. Barry, E. S. Shuman, E. B. Norrgard, and D. DeMille, to be published. We calculate that for molecules with near-cycling transitions, rapid laser BCF slowing should be possible.ootnotetextChieda, op. sit. For the CaF molecule, we predict slowing by δv = 150 m/s, enough to bring a buffer-gas cooled beam to rest. An experimental demonstration is in progress.

  18. Fan Atomized Burner design advances & commercial development progress

    SciTech Connect

    Kamath, B.; Butcher, T.A.

    1996-07-01

    As a part of the Oil Heat Research and Development program, sponsored by the US Department of Energy, Brookhaven National Laboratory (BNL) has an on-going interest in advanced combustion technologies. This interest is aimed at: improving the initial efficiency of heating equipment, reducing long term fouling and efficiency degradation, reducing air pollutant emissions, and providing practical low-firing rate technologies which may lead to new, high efficiency oil-fired appliances. The Fan-Atomized Burner (FAB) technology is being developed at BNL as part of this general goal. The Fan-Atomized Burner uses a low pressure, air atomizing nozzle in place of the high pressure nozzle used in conventional burners. Because it is air-atomized the burner can operate at low firing rates without the small passages and reliability concerns of low input pressure nozzles. Because it uses a low pressure nozzle the burner can use a fan in place of the small compressor used in other air-atomized burner designs. High initial efficiency of heating equipment is achieved because the burner can operate at very low excess air levels. These low excess air levels also reduce the formation of sulfuric acid in flames. Sulfuric acid is responsible for scaling and fouling of heat exchanger surfaces.

  19. The Scanning Electron Microscope As An Accelerator For The Undergraduate Advanced Physics Laboratory

    SciTech Connect

    Peterson, Randolph S.; Berggren, Karl K.; Mondol, Mark

    2011-06-01

    Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator for the undergraduate, advanced physics laboratory, the SEM is an excellent substitute for an ion accelerator. Although there are no nuclear physics experiments that can be performed with a typical 30 kV SEM, there is an opportunity for experimental work on accelerator physics, atomic physics, electron-solid interactions, and the basics of modern e-beam lithography.

  20. The Common Elements of Atomic and Hadronic Physics

    SciTech Connect

    Brodsky, Stanley J.

    2015-02-26

    Atomic physics and hadronic physics are both governed by the Yang Mills gauge theory Lagrangian; in fact, Abelian quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics can provide important insight into hadronic eigenstates in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of frame-independent light-front relativistic equations of motion consistent with light-front holography which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The production of antihydrogen in flight can provide important insight into the dynamics of hadron production in QCD at the amplitude level. The renormalization scale for the running coupling is unambiguously set in QED; an analogous procedure sets the renormalization scales in QCD, leading to scheme-independent scale-fixed predictions. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, the quark-interchange process and light-front quantization have important applicants for atomic physics and photon science, especially in the relativistic domain.

  1. Her Physics, His Physics: Gender Issues in Israeli Advanced Placement Physics Classes.

    ERIC Educational Resources Information Center

    Zohar, Anat; Sela, David

    2003-01-01

    Investigates gender issues in Israeli advanced placement physics classes. Analyzes matriculation exam scores from approximately 400 high schools over 12 years. Conducts semi-constructed interviews with 50 advanced placement physics students (25 girls and 25 boys). Discusses changes in the ratio of girls, performance, and factors that are…

  2. Majorana: From Atomic and Molecular, to Nuclear Physics

    NASA Astrophysics Data System (ADS)

    Pucci, R.; Angilella, G. G. N.

    2006-10-01

    In the centennial of Ettore Majorana's birth (1906-1938?), we re-examine some aspects of his fundamental scientific production in atomic and molecular physics, including a not well known short communication. There, Majorana critically discusses Fermi's solution of the celebrated Thomas-Fermi equation for electron screening in atoms and positive ions. We argue that some of Majorana's seminal contributions in molecular physics already prelude to the idea of exchange interactions (or Heisenberg-Majorana forces) in his later workson theoretical nuclear physics. In all his papers, he tended to emphasize the symmetries at the basis of a physical problem, as well as the limitations, rather than the advantages, of the approximations of the method employed.

  3. Recent technical advancements enabled atomic resolution CryoEM

    NASA Astrophysics Data System (ADS)

    Xueming, Li

    2016-01-01

    With recent breakthroughs in camera and image processing technologies single-particle electron cryo-microscopy (CryoEM) has suddenly gained the attention of structural biologists as a powerful tool able to solve the atomic structures of biological complexes and assemblies. Compared with x-ray crystallography, CryoEM can be applied to partially flexible structures in solution and without the necessity of crystallization, which is especially important for large complexes and assemblies. This review briefly explains several key bottlenecks for atomic resolution CryoEM, and describes the corresponding solutions for these bottlenecks based on the recent technical advancements. The review also aims to provide an overview about the technical differences between its applications in biology and those in material science. Project supported by Tsinghua-Peking Joint Center for Life Sciences, China.

  4. Bringing atomic and nuclear physics laboratory data into the classroom

    SciTech Connect

    Norman, Eric B.; Larimer, Ruth-Mary; Rech, Gregory; Lee, Jeffrey; Vue, Chue; Leubane, Tholoana; Zamvil, Kenneth; Guthrie, Laura

    2003-05-27

    To illustrate a number of basic concepts in atomic and nuclear physics, we have developed three websites where students can analyze data from modern laboratories. By working through the on-line procedures, students will become acquainted with characteristic x-ray spectra, the concept of half-life, x-ray fluorescence, and neutron activation analysis.

  5. ATOMIC PHYSICS, AN AUTOINSTRUCTIONAL PROGRAM, VOLUME 3, SUPPLEMENT.

    ERIC Educational Resources Information Center

    DETERLINE, WILLIAM A.; KLAUS, DAVID J.

    THE AUTOINSTRUCTIONAL MATERIALS IN THIS TEXT WERE PREPARED FOR USE IN AN EXPERIMENTAL STUDY, OFFERING SELF-TUTORING MATERIAL FOR LEARNING ATOMIC PHYSICS. THE TOPICS COVERED ARE (1) NUCLEAR BINDING ENERGY, (2) DISCOVERY OF RADIOACTIVITY, (3) RADIOACTIVE RADIATIONS, (4) ALPHA AND BETA DECAY, (5) BETA DECAY REACTIONS, (6) RADIOACTIVE DATING AND…

  6. Project Physics Reader 5, Models of the Atom.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    As a supplement to Project Physics Unit 5, a collection of articles is presented in this reader for student browsing. Nine excerpts are given under the following headings: failure and success, Einstein, Mr. Tompkins and simultaneity, parable of the surveyors, outside and inside the elevator, the teacher and the Bohr theory of atom, Dirac and Born,…

  7. ATOMIC PHYSICS, AN AUTOINSTRUCTIONAL PROGRAM, VOLUME 4, SUPPLEMENT.

    ERIC Educational Resources Information Center

    DETERLINE, WILLIAM A.; KLAUS, DAVID J.

    THE AUTOINSTRUCTIONAL MATERIALS IN THIS TEXT WERE PREPARED FOR USE IN AN EXPERIMENTAL STUDY, OFFERING SELF-TUTORING MATERIAL FOR LEARNING ATOMIC PHYSICS. THE TOPICS COVERED ARE (1) RADIATION USES AND NUCLEAR FISSION, (2) NUCLEAR REACTORS, (3) ENERGY FROM NUCLEAR REACTORS, (4) NUCLEAR EXPLOSIONS AND FUSION, (5) A COMPREHENSIVE REVIEW, AND (6) A…

  8. Physics and Advanced Technologies 2001 Annual Report

    SciTech Connect

    Jacobs, R

    2002-05-09

    The Physics and Advanced Technologies (PAT) Directorate was created in July 2000 by Bruce Tarter, Director of Lawrence Livermore National Laboratory (LLNL). The Director called for the new organization to execute and support programs that apply cutting-edge physics and advanced technology to develop integrated solutions to problems in national security, fusion energy, information science, health care, and other national grand challenges. When I was appointed a year later as the PAT Directorate's first Associate Director, I initiated a strategic planning project to develop a vision, mission, and long-term goals for the Directorate. We adopted the goal of becoming a leader in frontier physics and technology for twenty-first-century national security missions: Stockpile Stewardship, homeland security, energy independence, and the exploration of space. Our mission is to: (1) Help ensure the scientific excellence and vitality of the major LLNL programs through its leadership role in performing basic and applied multidisciplinary research and development with programmatic impact, and by recruiting and retaining science and technology leaders; (2) Create future opportunities and directions for LLNL and its major programs by growing new program areas and cutting-edge capabilities that are synergistic with, and supportive of, its national security mission; (3) Provide a direct conduit to the academic and high-tech industrial sectors for LLNL and its national security programs, through which the Laboratory gains access to frontier science and technology, and can impact the science and technology communities; (4) Leverage unique Laboratory capabilities, to advance the state universe. This inaugural PAT Annual Report begins a series that will chronicle our progress towards fulfilling this mission. I believe the report demonstrates that the PAT Directorate has a strong base of capabilities and accomplishments on which to build in meeting its goals. Some of the highlights

  9. Advanced satellite sensors: Low Energy Neutral Atom (LENA) imager

    SciTech Connect

    Funsten, H.O.; McComas, D.J.

    1996-09-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Imaging of low energy neutral atoms (LENDs) created by electron capture by magnetospheric plasma ions from interactions with cold geocoronal neutrals promises to be a revolutionary technique for providing unprecedented information about the global structure and dynamics of the terrestrial magnetosphere. This has significant implications in space weather forecasting, weather-induced satellite upset diagnostics, and revolutionary insights into global magnetospheric physics. The Los Alamos Space and Atmospheric Sciences Group has completed extensive neutral atom simulations and detailed instrument definition, and we designed a proof-of-concept demonstration prototype and have obtained externally- funded programs for full instrument development

  10. Atomic physics with highly charged ions. Progress report

    SciTech Connect

    Richard, P.

    1994-08-01

    The study of inelastic collision phenomena with highly charged projectile ions and the interpretation of spectral features resulting from these collisions remain as the major focal points in the atomic physics research at the J.R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas. The title of the research project, ``Atomic Physics with Highly Charged Ions,`` speaks to these points. The experimental work in the past few years has divided into collisions at high velocity using the primary beams from the tandem and LINAC accelerators and collisions at low velocity using the CRYEBIS facility. Theoretical calculations have been performed to accurately describe inelastic scattering processes of the one-electron and many-electron type, and to accurately predict atomic transition energies and intensities for x rays and Auger electrons. Brief research summaries are given for the following: (1) electron production in ion-atom collisions; (2) role of electron-electron interactions in two-electron processes; (3) multi-electron processes; (4) collisions with excited, aligned, Rydberg targets; (5) ion-ion collisions; (6) ion-molecule collisions; (7) ion-atom collision theory; and (8) ion-surface interactions.

  11. Strong field atomic physics in the mid-infrared

    SciTech Connect

    Sheehy, B; Martin, J D D; Clatterbuck, T O; Kim, D W; DiMauro, L F; Agostini, P; Schafer, K J; Gaarde, M B; Kulander, K C

    2000-03-15

    We examine strong field atomic physics in a wavelength region (3-4 microns) where very little work has previously been done. The soft photon energy allows the exploration of one-electron atoms with low binding energies (alkali metals). We find that photoionization spectra differ from rare gas studies at shorter wavelengths due to more complex ion core potentials. Harmonic generation is studied, and we find that harmonic bandwidths are consistent with theory and the possibility of compression to pulse widths much shorter than that of the driving pulse. Harmonic yields in the visible and W are sufficient for a complete study of their amplitude and phase characteristics.

  12. Eagleworks Laboratories: Advanced Propulsion Physics Research

    NASA Technical Reports Server (NTRS)

    White, Harold; March, Paul; Williams, Nehemiah; ONeill, William

    2011-01-01

    NASA/JSC is implementing an advanced propulsion physics laboratory, informally known as "Eagleworks", to pursue propulsion technologies necessary to enable human exploration of the solar system over the next 50 years, and enabling interstellar spaceflight by the end of the century. This work directly supports the "Breakthrough Propulsion" objectives detailed in the NASA OCT TA02 In-space Propulsion Roadmap, and aligns with the #10 Top Technical Challenge identified in the report. Since the work being pursued by this laboratory is applied scientific research in the areas of the quantum vacuum, gravitation, nature of space-time, and other fundamental physical phenomenon, high fidelity testing facilities are needed. The lab will first implement a low-thrust torsion pendulum (<1 uN), and commission the facility with an existing Quantum Vacuum Plasma Thruster. To date, the QVPT line of research has produced data suggesting very high specific impulse coupled with high specific force. If the physics and engineering models can be explored and understood in the lab to allow scaling to power levels pertinent for human spaceflight, 400kW SEP human missions to Mars may become a possibility, and at power levels of 2MW, 1-year transit to Neptune may also be possible. Additionally, the lab is implementing a warp field interferometer that will be able to measure spacetime disturbances down to 150nm. Recent work published by White [1] [2] [3] suggests that it may be possible to engineer spacetime creating conditions similar to what drives the expansion of the cosmos. Although the expected magnitude of the effect would be tiny, it may be a "Chicago pile" moment for this area of physics.

  13. Essay: Fifty years of atomic, molecular and optical physics in Physical Review Letters.

    PubMed

    Haroche, Serge

    2008-10-17

    The fiftieth anniversary of Physical Review Letters is a good opportunity to review the extraordinary progress of atomic, molecular, and optical physics reported in this journal during the past half-century. As both a witness and an actor of this story, I recall personal experiences and reflect about the past, present, and possible future of my field of research.

  14. Theoretical atomic physics code development I: CATS: Cowan Atomic Structure Code

    SciTech Connect

    Abdallah, J. Jr.; Clark, R.E.H.; Cowan, R.D.

    1988-12-01

    An adaptation of R.D. Cowan's Atomic Structure program, CATS, has been developed as part of the Theoretical Atomic Physics (TAPS) code development effort at Los Alamos. CATS has been designed to be easy to run and to produce data files that can interface with other programs easily. The CATS produced data files currently include wave functions, energy levels, oscillator strengths, plane-wave-Born electron-ion collision strengths, photoionization cross sections, and a variety of other quantities. This paper describes the use of CATS. 10 refs.

  15. Physically representative atomistic modeling of atomic-scale friction

    NASA Astrophysics Data System (ADS)

    Dong, Yalin

    Nanotribology is a research field to study friction, adhesion, wear and lubrication occurred between two sliding interfaces at nano scale. This study is motivated by the demanding need of miniaturization mechanical components in Micro Electro Mechanical Systems (MEMS), improvement of durability in magnetic storage system, and other industrial applications. Overcoming tribological failure and finding ways to control friction at small scale have become keys to commercialize MEMS with sliding components as well as to stimulate the technological innovation associated with the development of MEMS. In addition to the industrial applications, such research is also scientifically fascinating because it opens a door to understand macroscopic friction from the most bottom atomic level, and therefore serves as a bridge between science and engineering. This thesis focuses on solid/solid atomic friction and its associated energy dissipation through theoretical analysis, atomistic simulation, transition state theory, and close collaboration with experimentalists. Reduced-order models have many advantages for its simplification and capacity to simulating long-time event. We will apply Prandtl-Tomlinson models and their extensions to interpret dry atomic-scale friction. We begin with the fundamental equations and build on them step-by-step from the simple quasistatic one-spring, one-mass model for predicting transitions between friction regimes to the two-dimensional and multi-atom models for describing the effect of contact area. Theoretical analysis, numerical implementation, and predicted physical phenomena are all discussed. In the process, we demonstrate the significant potential for this approach to yield new fundamental understanding of atomic-scale friction. Atomistic modeling can never be overemphasized in the investigation of atomic friction, in which each single atom could play a significant role, but is hard to be captured experimentally. In atomic friction, the

  16. Advanced Electrochemistry of Individual Metal Clusters Electrodeposited Atom by Atom to Nanometer by Nanometer.

    PubMed

    Kim, Jiyeon; Dick, Jeffrey E; Bard, Allen J

    2016-11-15

    Metal clusters are very important as building blocks for nanoparticles (NPs) for electrocatalysis and electroanalysis in both fundamental and applied electrochemistry. Attention has been given to understanding of traditional nucleation and growth of metal clusters and to their catalytic activities for various electrochemical applications in energy harvesting as well as analytical sensing. Importantly, understanding the properties of these clusters, primarily the relationship between catalysis and morphology, is required to optimize catalytic function. This has been difficult due to the heterogeneities in the size, shape, and surface properties. Thus, methods that address these issues are necessary to begin understanding the reactivity of individual catalytic centers as opposed to ensemble measurements, where the effect of size and morphology on the catalysis is averaged out in the measurement. This Account introduces our advanced electrochemical approaches to focus on each isolated metal cluster, where we electrochemically fabricated clusters or NPs atom by atom to nanometer by nanometer and explored their electrochemistry for their kinetic and catalytic behavior. Such approaches expand the dimensions of analysis, to include the electrochemistry of (1) a discrete atomic cluster, (2) solely a single NP, or (3) individual NPs in the ensemble sample. Specifically, we studied the electrocatalysis of atomic metal clusters as a nascent electrocatalyst via direct electrodeposition on carbon ultramicroelectrode (C UME) in a femtomolar metal ion precursor. In addition, we developed tunneling ultramicroelectrodes (TUMEs) to study electron transfer (ET) kinetics of a redox probe at a single metal NP electrodeposited on this TUME. Owing to the small dimension of a NP as an active area of a TUME, extremely high mass transfer conditions yielded a remarkably high standard ET rate constant, k(0), of 36 cm/s for outer-sphere ET reaction. Most recently, we advanced nanoscale

  17. Advanced double-biprism holography with atomic resolution.

    PubMed

    Genz, Florian; Niermann, Tore; Buijsse, Bart; Freitag, Bert; Lehmann, Michael

    2014-12-01

    The optimum biprism position as suggested by Lichte (Ultramicroscopy 64 (1996) 79 [10]) was implemented into a state-of-the-art transmission electron microscope. For a setup optimized for atomic resolution holograms with a width of 30nm and a fringe spacing of 30pm, we investigated the practical improvements on hologram quality. The setup is additionally supplemented by a second biprism as suggested by Harada et al. (Applied Physics Letters 84 (2004) 3229 [12]). In order to estimate the possibilities and limitations of the double biprism setup, geometric optics arguments lead to calculation of the exploitable shadow width, necessary for strong reduction of biprism-induced artefacts. Additionally, we used the double biprism setup to estimate the biprism vibration, yielding the most stable imaging conditions with lowest overall fringe contrast damping. Electron holograms of GaN demonstrate the good match between experiment and simulation, also as a consequence of the improved stability.

  18. Advanced physical fine coal cleaning: Final report

    SciTech Connect

    Not Available

    1987-12-01

    The contract objective was to demonstrate Advanced Energy Dynamics, Inc., (AED) Ultrafine Coal (UFC) electrostatic physical fine coal cleaning process as capable of: producing clean coal products of no greater than 2% ash; significantly reducing the pyritic sulfur content below that achievable with state-of-the-art coal cleaning; recovering over 80% of the available energy content in the run-of-mine coal; producing product and refuse with surface moisture below 30%. Originally the demonstration was to be of a Charger/Disc System at the Electric Power Research Institute (EPRI) Coal Quality Development Center (CQDC) at Homer City, Pennsylvania. As a result of the combination of Charger/Disc System scale-up problems and parallel development of an improved Vertical-Belt Separator, DOE issued a contract modification to perform additional laboratory testing and optimization of the UFC Vertical-Belt Separator System at AED. These comparative test results, safety analyses and an economic analysis are discussed in this report. 29 refs., 25 figs., 41 tabs.

  19. Analysis of the physical atomic forces between noble gas atoms, alkali ions and halogen ions

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Heinbockel, J. H.; Outlaw, R. A.

    1986-01-01

    The physical forces between atoms and molecules are important in a number of processes of practical importance, including line broadening in radiative processes, gas and crystal properties, adhesion, and thin films. The components of the physical forces between noble gas atoms, alkali ions, and halogen ions are analyzed and a data base for the dispersion forces is developed from the literature based on evaluations with the harmonic oscillator dispersion model for higher order coefficients. The Zener model of the repulsive core is used in the context of the recent asymptotic wave functions of Handler and Smith; and an effective ionization potential within the Handler and Smith wave functions is defined to analyze the two body potential data of Waldman and Gordon, the alkali-halide molecular data, and the noble gas crystal and salt crystal data. A satisfactory global fit to this molecular and crystal data is then reproduced by the model to within several percent. Surface potentials are evaluated for noble gas atoms on noble gas and salt crystal surfaces with surface tension neglected. Within this context, the noble gas surface potentials on noble gas and salt crystals are considered to be accurate to within several percent.

  20. Advanced Dark Energy Physics Telescope (ADEPT)

    SciTech Connect

    Charles L. Bennett

    2009-03-26

    In 2006, we proposed to NASA a detailed concept study of ADEPT (the Advanced Dark Energy Physics Telescope), a potential space mission to reliably measure the time-evolution of dark energy by conducting the largest effective volume survey of the universe ever done. A peer-review panel of scientific, management, and technical experts reported back the highest possible 'excellent' rating for ADEPT. We have since made substantial advances in the scientific and technical maturity of the mission design. With this Department of Energy (DOE) award we were granted supplemental funding to support specific extended research items that were not included in the NASA proposal, many of which were intended to broadly advance future dark energy research, as laid out by the Dark Energy Task Force (DETF). The proposed work had three targets: (1) the adaptation of large-format infrared arrays to a 2 micron cut-off; (2) analytical research to improve the understanding of the dark energy figure-of- merit; and (3) extended studies of baryon acoustic oscillation systematic uncertainties. Since the actual award was only for {approx}10% of the proposed amount item (1) was dropped and item (2) work was severely restricted, consistent with the referee reviews of the proposal, although there was considerable contradictions between reviewer comments and several comments that displayed a lack of familiarity with the research. None the less, item (3) was the focus of the work. To characterize the nature of the dark energy, ADEPT is designed to observe baryon acoustic oscillations (BAO) in a large galaxy redshift survey and to obtain substantial numbers of high-redshift Type Ia supernovae (SNe Ia). The 2003 Wilkinson Microwave Anisotropy Probe (WMAP) made a precise determination of the BAO 'standard ruler' scale, as it was imprinted on the cosmic microwave background (CMB) at z {approx} 1090. The standard ruler was also imprinted on the pattern of galaxies, and was first detected in 2005 in Sloan

  1. Physics and Advanced Technologies 2003 Annual Report

    SciTech Connect

    Hazi, A; Sketchley, J

    2005-01-20

    The Physics and Advanced Technologies (PAT) Directorate overcame significant challenges in 2003 to deliver a wealth of scientific and programmatic milestones, and move toward closer alignment with programs at Lawrence Livermore National Laboratory. We acted aggressively in enabling the PAT Directorate to contribute to future, growing Lawrence Livermore missions in homeland security and at the National Ignition Facility (NIF). We made heavy investments to bring new capabilities to the Laboratory, to initiate collaborations with major Laboratory programs, and to align with future Laboratory directions. Consistent with our mission, we sought to ensure that Livermore programs have access to the best science and technology, today and tomorrow. For example, in a move aimed at revitalizing the Laboratory's expertise in nuclear and radiation detection, we brought the talented Measurement Sciences Group to Livermore from Lawrence Berkeley National Laboratory, after its mission there had diminished. The transfer to our I Division entailed significant investment by PAT in equipment and infrastructure required by the group. In addition, the move occurred at a time when homeland security funding was expected, but not yet available. By the end of the year, though, the group was making crucial contributions to the radiation detection program at Livermore, and nearly every member was fully engaged in programmatic activities. Our V Division made a move of a different sort, relocating en masse from Building 121 to the NIF complex. This move was designed to enhance interaction and collaboration among high-energy-density experimental scientists at the Laboratory, a goal that is essential to the effective use of NIF in the future. Since then, V Division has become increasingly integrated with NIF activities. Division scientists are heavily involved in diagnostic development and fielding and are poised to perform equation-of-state and high-temperature hohlraum experiments in 2004 as

  2. Atom Interferometry for Fundamental Physics and Gravity Measurements in Space

    NASA Technical Reports Server (NTRS)

    Kohel, James M.

    2012-01-01

    Laser-cooled atoms are used as freefall test masses. The gravitational acceleration on atoms is measured by atom-wave interferometry. The fundamental concept behind atom interferometry is the quantum mechanical particle-wave duality. One can exploit the wave-like nature of atoms to construct an atom interferometer based on matter waves analogous to laser interferometers.

  3. ITER core imaging X-ray spectroscopy: Atomic physics issues

    NASA Astrophysics Data System (ADS)

    Beiersdorfer, P.; Clementson, J.; Widmann, K.; Bitter, M.; Hill, K. W.; Johnson, D.; Barnsley, R.; Chung, H. K.; Safronova, U. I.

    2017-03-01

    The Core Imaging X-Ray Spectrometer (CIXS) will be employed for measurements of the ion temperature and of the toroidal rotation velocity, Ti and vϕ, respectively, as a function of the radius of ITER plasmas. The diagnostic is based on precision determinations of the Doppler broadening, centroid shift, and intensity of the lines of highly ionized heavy impurities using a curved Bragg crystal spectral disperser and imager. The ions under consideration for the diagnostic are those of tungsten, krypton, xenon, iron, and argon. A detailed discussion is given of the need for atomic physics experiments and calculations involving the primary diagnostic lines and their collisional and dielectronic satellites. Such experiments and calculations define the instrument parameters, determine the diagnostic uncertainties, and provide paths for extending the diagnostic capabilities to measure impurity concentrations, electron temperature, and ion transport parameters. Enabling the diagnostic to measure radially dependent ion transport coefficients, in particular, requires a large amount of high-quality atomic data in the form of reliable excitation, ionization, and recombination rate coefficients as well as ionization balance calculations which make use of these data. Because core imaging spectrometers are being developed and implemented on present-day magnetic fusion devices, much of the atomic data are already needed and can be tested in the analysis of existing spectra recorded by these diagnostics.

  4. Atomic Structure. Independent Learning Project for Advanced Chemistry (ILPAC). Unit S2.

    ERIC Educational Resources Information Center

    Inner London Education Authority (England).

    This unit on atomic structure is one of 10 first year units produced by the Independent Learning Project for Advanced Chemistry (ILPAC). The unit consists of two levels. Level one focuses on the atomic nucleus. Level two focuses on the arrangement of extranuclear electrons, approaching atomic orbitals through both electron bombardment and spectra.…

  5. Advances in the atomic force microscopy for critical dimension metrology

    NASA Astrophysics Data System (ADS)

    Hussain, Danish; Ahmad, Khurshid; Song, Jianmin; Xie, Hui

    2017-01-01

    Downscaling, miniaturization and 3D staking of the micro/nano devices are burgeoning phenomena in the semiconductor industry which have posed sophisticated challenges in the critical dimension (CD) metrology. Over the past few years, atomic force microscopy (AFM) has emerged as an important CD metrology technique in meeting these challenges because of its high accuracy, 3D imaging capability, high spatial resolution and non-destructive nature. In this article, advances in the AFM based critical dimension (CD) metrology are systematically reviewed and discussed. CD metrology AFM techniques, strengths, limitations and scanning algorithms are described. Developments towards accurate measurements such as creep and hysteresis compensation of the piezoelectric scanners, their calibration and tip characterization are discussed. In addition, image reconstruction and measures for achieving high accuracy CD measurements with hybrid metrology technique are also discussed. CD metrology challenges offered by the next generation lithography (NGL) techniques such as those associated with the 3D nanodevices of 10 nm node and beyond have been highlighted.

  6. Atomic, Molecular, and Optical Physics Workshop Final Report

    SciTech Connect

    Armstrong, Jr., Lloyd

    1997-09-21

    This document contains the final reports from the five panels that comprised a Workshop held to explore future directions, scientific impacts and technological connections of research in Atomic, Molecular and Optical Physics. This workshop was sponsored by the Department of Energy, Office of Basic Energy Sciences, Chemical Sciences Division and was held at the Westfields International Conference Center in Chantilly, Virginia on September 21-24, 1997. The workshop was chaired by Lloyd Armstrong, Jr., University of Southern California and the five panels focused on the following topics: Panel A: Interactions of Atoms and Molecules with Photons - Low Field Daniel Kleppner (Massachusetts Institute of Technology), chair Panel B: Interactions of Atoms and Molecules with Photons - High Field Phil Bucksbaum (University of Michigan), chair Panel C: Surface Interactions with Photons, Electrons, Ions, Atoms and Molecules J. Wayne Rabalais (University of Houston), chair Panel D: Theory of Structure and Dynamics Chris Greene (University of Colorado), chair Panel E: Nano- and Mesocopic Structures Paul Alivisatos (Lawrence Berkeley National Laboratory), chair The choice of focus areas reflects areas of significant interest to DOE/BES but is clearly not intended to span all fields encompassed by the designation of atomic, molecular and optical physics, nor even all areas that would be considered for review and funding under DOE’s AMOP program. In a similar vein, not all research that might be suggested under these topics in this report would be appropriate for consideration by DOE’s AMOP program. The workshop format included overview presentations from each of the panel chairs, followed by an intensive series of panel discussion sessions held over a two-day period. The panels were comprised of scientists from the U. S. and abroad, many of whom are not supported by DOE’s AMOP Program. This workshop was held in lieu of the customary “Contractors Meeting” held annually for

  7. The Physical Conditions of Atomic Gas at High Redshift

    NASA Astrophysics Data System (ADS)

    Neeleman, Marcel

    In this thesis we provide insight into the chemical composition, physical conditions and cosmic distribution of atomic gas at high redshift. We study this gas in absorption against bright background quasars in absorption systems known as Damped Ly-alpha Systems (DLAs). These systems contain the bulk of the atomic gas at high redshift and are the likely progenitors of modern-day galaxies. In Chapter 2, we find that the atomic gas in DLAs obeys a mass-metallicity relationship that is similar to the mass-metallicity relationship seen in star-forming galaxies. The evolution of this relationship is linear with redshift, allowing for a planar equation to accurately describe this evolution, which provides a more stringent constraint on simulations modeling DLAs. Furthermore, the concomitant evolution of the mass-metallicity relationship of atomic gas and star-forming galaxies suggests an intimate link between the two. We next use a novel way to measure the physical conditions of the gas by using fine-structure line ratios of singly ionized carbon and silicon. By measuring the density of the upper and lower level states, we are able to determine the temperature, hydrogen density and electron density of the gas. We find that the conditions present in this high redshift gas are consistent with the conditions we see in the local interstellar medium (ISM). A few absorbers have higher than expected pressure, which suggests that they probe the ISM of star-forming galaxies. Finally in Chapter 4, we measure the cosmic neutral hydrogen density at redshifts below 1.6. Below this redshift, the Ly-alpha line of hydrogen is absorbed by the atmosphere, making detection difficult. Using the archive of the Hubble Space Telescope, we compile a comprehensive list of quasars for a search of DLAs at redshift below 1.6. We find that the incidence rate of DLAs and the cosmic neutral hydrogen density is smaller than previously measured, but consistent with the values both locally and at

  8. Atomic force microscopy as an advanced tool in neuroscience

    PubMed Central

    Jembrek, Maja Jazvinšćak; Šimić, Goran; Hof, Patrick R.; Šegota, Suzana

    2015-01-01

    This review highlights relevant issues about applications and improvements of atomic force microscopy (AFM) toward a better understanding of neurodegenerative changes at the molecular level with the hope of contributing to the development of effective therapeutic strategies for neurodegenerative illnesses. The basic principles of AFM are briefly discussed in terms of evaluation of experimental data, including the newest PeakForce Quantitative Nanomechanical Mapping (QNM) and the evaluation of Young’s modulus as the crucial elasticity parameter. AFM topography, revealed in imaging mode, can be used to monitor changes in live neurons over time, representing a valuable tool for high-resolution detection and monitoring of neuronal morphology. The mechanical properties of living cells can be quantified by force spectroscopy as well as by new AFM. A variety of applications are described, and their relevance for specific research areas discussed. In addition, imaging as well as non-imaging modes can provide specific information, not only about the structural and mechanical properties of neuronal membranes, but also on the cytoplasm, cell nucleus, and particularly cytoskeletal components. Moreover, new AFM is able to provide detailed insight into physical structure and biochemical interactions in both physiological and pathophysiological conditions. PMID:28123795

  9. Davisson-Germer Prize in Atomic or Surface Physics Lecture: Exploring Flatland with Cold Atoms

    NASA Astrophysics Data System (ADS)

    Dalibard, Jean

    2012-06-01

    A two-dimensional Bose fluid is a remarkably rich many-body system, which allows one to revisit several features of quantum statistical physics. Firstly, the role of thermal fluctuations is enhanced compared to the 3D case, which destroys the ordered state associated with Bose-Einstein condensation. However interactions between particles can still cause a superfluid transition, thanks to the Berezinskii-Kosterlitz-Thouless mechanism. Secondly, a weakly interacting Bose fluid in 2D must be scale-invariant, a remarkable feature that manifests itself in the very simple form taken by the equation of state of the fluid. In this talk I will present recent experimental progress in the investigation of 2D atomic gases, which provide a nice illustration of the main features of low dimensional many-body physics.

  10. Use of the Berkeley Physics Laboratory to Teach an Advanced Physics Course

    ERIC Educational Resources Information Center

    Logan, James David

    1973-01-01

    Discusses a course, centered around 32 experiments taught for advanced students, designed to develop a laboratory strongly suggestive of contemporary research using relatively sophisticated apparatus. Its unique advantage lies in enriching advanced physics curriculum. (DF)

  11. PREFACE: Atomically controlled fabrication technology: new physics and functional device realization Atomically controlled fabrication technology: new physics and functional device realization

    NASA Astrophysics Data System (ADS)

    Kuwahara, Yuji; Kasai, Hideaki

    2011-10-01

    To realize next generation functional devices, atomic level controllability of the application and fabrication techniques is necessary. The conventional route to advance solid state devices, which involves improvement of 'instrumental accuracy', is now facing a major paradigm shift towards 'phenomenal accuracy'. Therefore, to keep up with this critical turn in the development of devices, pioneering research (both theoretical and experimental) on relevant materials, focusing on new physics at the atomic scale, is inevitable. This special section contains articles on the advancements in fabrication of functional devices with an emphasis on the exploration, clarification and understanding of atomistic phenomena. Research articles reporting theoretical and experimental findings on various materials such as semiconductors, metals, magnetic and organic systems, collectively present and 'capture' the appropriate processes and mechanisms of this rapidly developing field. The theoretical investigations employ first-principles quantum-mechanical simulations to clarify and bring about design principles and guidelines, or to develop more reliable computational methods. Experimental studies, on the other hand, introduce novel capabilities to build, view and manipulate materials at the atomic scale by employing pioneering techniques. Thus, the section pays significant attention to novel structures and properties and the accompanying fabrication techniques and design arising from the understanding of properties and structures at the atomic scale. We hope that researchers in the area of physics, materials science and engineering, interested in the development of functional devices via atomic level control, will find valuable information in this collaborative work. We are grateful to all of the authors for their contributions. Atomically controlled fabrication contents On the mechanism of carbon nanotube formation: the role of the catalyst G N Ayre, T Uchino, B Mazumder, A L Hector

  12. NEW APPROACHES: Reading in Advanced level physics

    NASA Astrophysics Data System (ADS)

    Fagan, Dorothy

    1997-11-01

    Teachers often report that their A-level pupils are unwilling to read physics-related material. What is it about physics texts that deters pupils from reading them? Are they just too difficult for 16 - 18 year olds, or is it that pupils lack specific reading skills? This article describes some of the results from my research into pupils' reading of physics-related texts and tries to clarify the situation.

  13. Atom optics and space physics: A summary of an 'Enrico Fermi' summer school

    NASA Astrophysics Data System (ADS)

    Arimondo, Ennio; Ertmer, Wolfgang; Rasel, Ernst M.; Schleich, Wolfgang P.

    2008-03-01

    We describe the scientific content of the International School of Physics 'Enrico Fermi' on atom optics and space physics, organized by the Italian Physical Society in Varenna at Lake Como, Italy, 2-13 July 2007.

  14. Phases and Interfaces from Real Space Atomically Resolved Data: Physics-Based Deep Data Image Analysis.

    PubMed

    Vasudevan, Rama K; Ziatdinov, Maxim; Jesse, Stephen; Kalinin, Sergei V

    2016-09-14

    Advances in electron and scanning probe microscopies have led to a wealth of atomically resolved structural and electronic data, often with ∼1-10 pm precision. However, knowledge generation from such data requires the development of a physics-based robust framework to link the observed structures to macroscopic chemical and physical descriptors, including single phase regions, order parameter fields, interfaces, and structural and topological defects. Here, we develop an approach based on a synergy of sliding window Fourier transform to capture the local analog of traditional structure factors combined with blind linear unmixing of the resultant 4D data set. This deep data analysis is ideally matched to the underlying physics of the problem and allows reconstruction of the a priori unknown structure factors of individual components and their spatial localization. We demonstrate the principles of this approach using a synthetic data set and further apply it for extracting chemical and physically relevant information from electron and scanning tunneling microscopy data. This method promises to dramatically speed up crystallographic analysis in atomically resolved data, paving the road toward automatic local structure-property determinations in crystalline and quasi-ordered systems, as well as systems with competing structural and electronic order parameters.

  15. Phases and interfaces from real space atomically resolved data: Physics-based deep data image analysis

    DOE PAGES

    Vasudevan, Rama K.; Ziatdinov, Maxim; Jesse, Stephen; ...

    2016-08-12

    Advances in electron and scanning probe microscopies have led to a wealth of atomically resolved structural and electronic data, often with ~1–10 pm precision. However, knowledge generation from such data requires the development of a physics-based robust framework to link the observed structures to macroscopic chemical and physical descriptors, including single phase regions, order parameter fields, interfaces, and structural and topological defects. Here, we develop an approach based on a synergy of sliding window Fourier transform to capture the local analog of traditional structure factors combined with blind linear unmixing of the resultant 4D data set. This deep data analysismore » is ideally matched to the underlying physics of the problem and allows reconstruction of the a priori unknown structure factors of individual components and their spatial localization. We demonstrate the principles of this approach using a synthetic data set and further apply it for extracting chemical and physically relevant information from electron and scanning tunneling microscopy data. Furthermore, this method promises to dramatically speed up crystallographic analysis in atomically resolved data, paving the road toward automatic local structure–property determinations in crystalline and quasi-ordered systems, as well as systems with competing structural and electronic order parameters.« less

  16. Phases and interfaces from real space atomically resolved data: Physics-based deep data image analysis

    SciTech Connect

    Vasudevan, Rama K.; Ziatdinov, Maxim; Jesse, Stephen; Kalinin, Sergei V.

    2016-08-12

    Advances in electron and scanning probe microscopies have led to a wealth of atomically resolved structural and electronic data, often with ~1–10 pm precision. However, knowledge generation from such data requires the development of a physics-based robust framework to link the observed structures to macroscopic chemical and physical descriptors, including single phase regions, order parameter fields, interfaces, and structural and topological defects. Here, we develop an approach based on a synergy of sliding window Fourier transform to capture the local analog of traditional structure factors combined with blind linear unmixing of the resultant 4D data set. This deep data analysis is ideally matched to the underlying physics of the problem and allows reconstruction of the a priori unknown structure factors of individual components and their spatial localization. We demonstrate the principles of this approach using a synthetic data set and further apply it for extracting chemical and physically relevant information from electron and scanning tunneling microscopy data. Furthermore, this method promises to dramatically speed up crystallographic analysis in atomically resolved data, paving the road toward automatic local structure–property determinations in crystalline and quasi-ordered systems, as well as systems with competing structural and electronic order parameters.

  17. The Los Alamos suite of relativistic atomic physics codes

    DOE PAGES

    Fontes, C. J.; Zhang, H. L.; Jr, J. Abdallah; ...

    2015-05-28

    The Los Alamos SuitE of Relativistic (LASER) atomic physics codes is a robust, mature platform that has been used to model highly charged ions in a variety of ways. The suite includes capabilities for calculating data related to fundamental atomic structure, as well as the processes of photoexcitation, electron-impact excitation and ionization, photoionization and autoionization within a consistent framework. These data can be of a basic nature, such as cross sections and collision strengths, which are useful in making predictions that can be compared with experiments to test fundamental theories of highly charged ions, such as quantum electrodynamics. The suitemore » can also be used to generate detailed models of energy levels and rate coefficients, and to apply them in the collisional-radiative modeling of plasmas over a wide range of conditions. Such modeling is useful, for example, in the interpretation of spectra generated by a variety of plasmas. In this work, we provide a brief overview of the capabilities within the Los Alamos relativistic suite along with some examples of its application to the modeling of highly charged ions.« less

  18. The Los Alamos suite of relativistic atomic physics codes

    SciTech Connect

    Fontes, C. J.; Zhang, H. L.; Jr, J. Abdallah; Clark, R. E. H.; Kilcrease, D. P.; Colgan, J.; Cunningham, R. T.; Hakel, P.; Magee, N. H.; Sherrill, M. E.

    2015-05-28

    The Los Alamos SuitE of Relativistic (LASER) atomic physics codes is a robust, mature platform that has been used to model highly charged ions in a variety of ways. The suite includes capabilities for calculating data related to fundamental atomic structure, as well as the processes of photoexcitation, electron-impact excitation and ionization, photoionization and autoionization within a consistent framework. These data can be of a basic nature, such as cross sections and collision strengths, which are useful in making predictions that can be compared with experiments to test fundamental theories of highly charged ions, such as quantum electrodynamics. The suite can also be used to generate detailed models of energy levels and rate coefficients, and to apply them in the collisional-radiative modeling of plasmas over a wide range of conditions. Such modeling is useful, for example, in the interpretation of spectra generated by a variety of plasmas. In this work, we provide a brief overview of the capabilities within the Los Alamos relativistic suite along with some examples of its application to the modeling of highly charged ions.

  19. Efimov Physics in a 6Li-133Cs Atomic Mixture

    NASA Astrophysics Data System (ADS)

    Johansen, Jacob; Feng, Lei; Parker, Colin; Chin, Cheng; Wang, Yujun

    2015-05-01

    We investigate Efimov physics based on three-body recombination in an atomic mixture of 6Li and 133Cs in the vicinity of interspecies Feshbach resonances at 843 and 889 G. This allows us to compare the loss spectra near different resonances and test the universality of Efimov states. Theoretically the Efimov spectrum near 889 G is expected to be similar to that near 843 G, except that the first resonance is absent near the former Feshbach resonance. This is due to the difference in the Cs-Cs scattering length near the two resonances: At 843 G it is negative, whereas at 889 G it is positive. Although it is primarily the Li-Cs interactions that lead to Efimov resonances, the Cs-Cs scattering length is expected to influence the spectrum. This work is supported by NSF and Chicago MRSEC.

  20. Advancing Successful Physics Majors - The Physics First Year Seminar Experience

    NASA Astrophysics Data System (ADS)

    Deibel, Jason; Petkie, Douglas

    In 2012, the Wright State University physics curriculum introduced a new year-long seminar course required for all new physics majors. The goal of this course is to improve student retention and success via building a community of physics majors and provide them with the skills, mindset, and advising necessary to successfully complete a degree and transition to the next part of their careers. This new course sequence assembles a new cohort of majors annually. To prepare each cohort, students engage in a variety of activities that span from student success skills to more specific physics content while building an entrepreneurial mindset. Students participate in activities including study skills, career night, course planning, campus services, and a department social function. More importantly, students gain exposure to programming, literature searches, data analysis, technical writing, elevator pitches, and experimental design via hands-on projects. This includes the students proposing, designing, and conducting their own experiments. Preliminary evidence indicates increased retention, student success, and an enhanced sense of community among physics undergraduate students, The overall number of majors and students eventually completing their physics degrees has nearly tripled. Associate Professor, Department of Physics.

  1. Educating Scientifically - Advances in Physics Education Research

    ScienceCinema

    Finkelstein, Noah [University of Colorado, Colorado, USA

    2016-07-12

    It is now fairly well documented that traditionally taught, large-scale introductory physics courses fail to teach our students the basics. In fact, often these same courses have been found to teach students things we do not want. Building on a tradition of research in physics, the physics education research community has been researching the effects of educational practice and reforms at the undergraduate level for many decades. From these efforts and those within the fields of education, cognitive science, and psychology we have learned a great deal about student learning and environments that support learning for an increasingly diverse population of students in the physics classroom. This talk will introduce some of the ideas from physics education research, discuss a variety of effective classroom practices/ surrounding educational structures, and begin to examine why these do (and do not) work. I will present both a survey of physics education research and some of the exciting theoretical and experimental developments emerging from the University of Colorado.

  2. Educating Scientifically: Advances in Physics Education Research

    SciTech Connect

    Finkelstein, Noah

    2007-05-16

    It is now fairly well documented that traditionally taught, large-scale introductory physics courses fail to teach our students the basics. In fact, often these same courses have been found to teach students things we do not want. Building on a tradition of research in physics, the physics education research community has been researching the effects of educational practice and reforms at the undergraduate level for many decades. From these efforts and those within the fields of education, cognitive science, and psychology we have learned a great deal about student learning and environments that support learning for an increasingly diverse population of students in the physics classroom. This talk will introduce some of the ideas from physics education research, discuss a variety of effective classroom practices/ surrounding educational structures, and begin to examine why these do (and do not) work. I will present both a survey of physics education research and some of the exciting theoretical and experimental developments emerging from the University of Colorado.

  3. Educating Scientifically - Advances in Physics Education Research

    SciTech Connect

    Finkelstein, Noah

    2007-05-16

    It is now fairly well documented that traditionally taught, large-scale introductory physics courses fail to teach our students the basics. In fact, often these same courses have been found to teach students things we do not want. Building on a tradition of research in physics, the physics education research community has been researching the effects of educational practice and reforms at the undergraduate level for many decades. From these efforts and those within the fields of education, cognitive science, and psychology we have learned a great deal about student learning and environments that support learning for an increasingly diverse population of students in the physics classroom. This talk will introduce some of the ideas from physics education research, discuss a variety of effective classroom practices/ surrounding educational structures, and begin to examine why these do (and do not) work. I will present both a survey of physics education research and some of the exciting theoretical and experimental developments emerging from the University of Colorado.

  4. PHYSICS OF POLARIZED SCATTERING AT MULTI-LEVEL ATOMIC SYSTEMS

    SciTech Connect

    Stenflo, J. O.

    2015-03-01

    The symmetric peak observed in linear polarization in the core of the solar sodium D{sub 1} line at 5896 Å has remained enigmatic since its discovery nearly two decades ago. One reason is that the theory of polarized scattering has not been experimentally tested for multi-level atomic systems in the relevant parameter domains, although the theory is continually being used for the interpretation of astrophysical observations. A laboratory experiment that was set up a decade ago to find out whether the D{sub 1} enigma is a problem of solar physics or quantum physics revealed that the D{sub 1} system has a rich polarization structure in situations where standard scattering theory predicts zero polarization, even when optical pumping of the m state populations of the hyperfine-split ground state is accounted for. Here we show that the laboratory results can be modeled in great quantitative detail if the theory is extended to include the coherences in both the initial and final states of the scattering process. Radiative couplings between the allowed dipole transitions generate coherences in the initial state. Corresponding coherences in the final state are then demanded by a phase closure selection rule. The experimental results for the well understood D{sub 2} line are used to constrain the two free parameters of the experiment, collision rate and optical depth, to suppress the need for free parameters when fitting the D{sub 1} results.

  5. Advances in the calibration of atom probe tomographic reconstruction

    SciTech Connect

    Gault, Baptiste; Moody, Michael P.; La Fontaine, Alexandre; Stephenson, Leigh T.; Haley, Daniel; Ringer, Simon P.; Geuser, Frederic de; Tsafnat, Guy

    2009-02-01

    Modern wide field-of-view atom probes permit observation of a wide range of crystallographic features that can be used to calibrate the tomographic reconstruction of the analyzed volume. In this study, methodologies to determine values of the geometric parameters involved in the tomographic reconstruction of atom probe data sets are presented and discussed. The influence of the tip to electrode distance and specimen temperature on these parameters is explored. Significantly, their influence is demonstrated to be very limited, indicating a relatively wide regime of experimental parameters space for sound atom probe tomography (APT) experiments. These methods have been used on several specimens and material types, and the results indicate that the reconstruction parameters are specific to each specimen. Finally, it is shown how an accurate calibration of the reconstruction enables improvements to the quality and reliability of the microscopy and microanalysis capabilities of the atom probe.

  6. Advances in Measurement Technology at NIST's Physical Measurement Laboratory

    NASA Astrophysics Data System (ADS)

    Dehmer, Joseph

    2014-03-01

    The NIST mission is to promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology. The Physical Measurement Laboratory (PML) has responsibility for maintaining national standards for two dozen physical quantities needed for international trade; and, importantly, it carries out advanced research at the frontiers of measurement science to enable extending innovation into new realms and new markets. This talk will highlight advances being made across several sectors of technology; and it will describe how PML interacts with its many collaborators and clients in industry, government, and academe.

  7. Advanced Computing Tools and Models for Accelerator Physics

    SciTech Connect

    Ryne, Robert; Ryne, Robert D.

    2008-06-11

    This paper is based on a transcript of my EPAC'08 presentation on advanced computing tools for accelerator physics. Following an introduction I present several examples, provide a history of the development of beam dynamics capabilities, and conclude with thoughts on the future of large scale computing in accelerator physics.

  8. ATOMIC PHYSICS, AN AUTOINSTRUCTIONAL PROGRAM, VOLUME 1, SUPPLEMENT.

    ERIC Educational Resources Information Center

    DETERLINE, WILLIAM A.; KLAUS, DAVID J.

    AUTOINSTRUCTIONAL MATERIALS WERE PREPARED FOR USE IN AN EXPERIMENTAL STUDY OF THE SELF-TUTORING APPROACH IN EDUCATION. THE MATERIALS COVER SECTIONS ON (1) THE ATOM, (2) ATOMIC PARTICLES, (3) CATHODE RAYS, (4) MEASURING THE ELECTRON, (5) CHARGE AND MASS OF THE ELECTRON, AND (6) MASS OF ATOMS. RELATED REPORTS ARE ED 003 205 THROUGH ED 003 207, ED…

  9. Project for the Institution of an Advanced Course in Physics

    NASA Astrophysics Data System (ADS)

    Teodorani, M.; Nobili, G.

    2006-06-01

    A project for an advanced course in physics at the master level, is presented in great detail. The goal of this project is to create a specific and rigorous training for those who want to carry out experimental and theoretical research on "anomalies" in physical science, especially from the point of view of atmospheric physics, plasma physics, photonic physics, biophysics, astronomy and astrophysics. A specific training in powering mental skills is planned as well. The planned teaching program is presented as a two-year course where the following subjects are intended to be taught: cognitive techniques (I and II), radiation physics (I and II), biophysics (I and II), bioastronomy (I and II), history of physics (I and II), didactics of physics, physics of atmospheric plasmas, physics of non-stationary photonic events, physics of non-linear processes, complements of quantum mechanics, quantum informatics, research methodology in physics and astronomy, computer science methods in physics and astronomy, optoelectronics, radioelectronics. Detailed teaching programs, didactics methods, and performance evaluation, are presented for each subject. The technical content of this project is preceded by an ample introduction that shows all the reasons of this kind of physics course, particularly aimed at innovation in physical science.

  10. Advanced Software Methods for Physics Analysis

    NASA Astrophysics Data System (ADS)

    Lista, L.

    2006-01-01

    Unprecedented data analysis complexity is experienced in modern High Energy Physics experiments. The complexity arises from the growing size of recorded data samples, the large number of data analyses performed by different users in each single experiment, and the level of complexity of each single analysis. For this reason, the requirements on software for data analysis impose a very high level of reliability. We present two concrete examples: the former from BaBar experience with the migration to a new Analysis Model with the definition of a new model for the Event Data Store, the latter about a toolkit for multivariate statistical and parametric Monte Carlo analysis developed using generic programming.

  11. Atomic physics in the quest for fusion energy and ITER

    NASA Astrophysics Data System (ADS)

    Skinner, Charles H.

    2009-05-01

    The urgent quest for new energy sources has led developed countries, representing over half of the world population, to collaborate on demonstrating the scientific and technological feasibility of magnetic fusion through the construction and operation of the international thermonuclear experimental reactor (ITER). Data on high-Z ions will be important in this quest. Tungsten plasma facing components have the necessary low erosion rates and low tritium retention but the high radiative efficiency of tungsten ions leads to stringent restrictions on the concentration of tungsten ions in the burning plasma. The influx of tungsten to the burning plasma will need to be diagnosed, understood and stringently controlled. Expanded knowledge of the atomic physics of neutral and ionized tungsten will be important to monitor impurity influxes and derive tungsten concentrations. Also, inert gases such as argon and xenon will be used to dissipate the heat flux flowing to the divertor. This paper will summarize the spectroscopic diagnostics planned for ITER and outline areas where additional data are needed.

  12. Difference-frequency combs in cold atom physics

    NASA Astrophysics Data System (ADS)

    Kliese, Russell; Hoghooghi, Nazanin; Puppe, Thomas; Rohde, Felix; Sell, Alexander; Zach, Armin; Leisching, Patrick; Kaenders, Wilhelm; Keegan, Niamh C.; Bounds, Alistair D.; Bridge, Elizabeth M.; Leonard, Jack; Adams, Charles S.; Cornish, Simon L.; Jones, Matthew P. A.

    2016-12-01

    Optical frequency combs provide the clockwork to relate optical frequencies to radio frequencies. Hence, combs allow optical frequencies to be measured with respect to a radio frequency where the accuracy is limited only by the reference signal. In order to provide a stable link between the radio and optical frequencies, the two parameters of the frequency comb must be fixed: the carrier envelope offset frequency, f ceo, and the pulse repetition-rate, f rep. We have developed the first optical frequency comb based on difference frequency generation (DFG) that eliminates f ceo by design — specifically tailored for applications in cold atom physics. An f ceo-free spectrum at 1550 nm is generated from a super continuum spanning more than an optical octave. Established amplification and frequency conversion techniques based on reliable telecom fibre technology allow the generation of multiple wavelength outputs. The DFG comb is a convenient tool to both stabilise laser sources and accurately measure optical frequencies in Rydberg experiments and more generally in quantum optics. In this paper we discuss the frequency comb design, characterization, and optical frequency measurement of Strontium Rydberg states. The DFG technique allows for a compact and robust, passively f ceo stable frequency comb significantly improving reliability in practical applications.

  13. Advanced Physical Chemistry of Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Li, Jun; Pandey, Gaind P.

    2015-04-01

    The past decade has seen a surge of exciting research and applications of carbon nanotubes (CNTs) stimulated by deeper understanding of their fundamental properties and increasing production capability. The intrinsic properties of various CNTs were found to strongly depend on their internal microstructures. This review summarizes the fundamental structure-property relations of seamless tube-like single- and multiwalled CNTs and conically stacked carbon nanofibers, as well as the organized architectures of these CNTs (including randomly stacked thin films, parallel aligned thin films, and vertically aligned arrays). It highlights the recent development of CNTs as key components in selected applications, including nanoelectronics, filtration membranes, transparent conductive electrodes, fuel cells, electrical energy storage devices, and solar cells. Particular emphasis is placed on the link between the basic physical chemical properties of CNTs and the organized CNT architectures with their functions and performance in each application.

  14. ALPhA: The Advanced Laboratory Physics Association

    NASA Astrophysics Data System (ADS)

    Black, Eric; McCann, Lowell; Reichert, Jonathan; Spalding, Gabe; Essick, John; van Baak, David; Wonnell, Steve

    2011-03-01

    The Advanced Laboratory Physics Association (ALPhA) is a group of people with a shared interest in teaching physics labs at the advanced undergraduate or graduate level. ALPhA works closely with the American Physical Society (APS), the Optical Society of America (OSA), and the American Association of Physics Teachers (AAPT) to develop new methods for teaching modern experimental physics. In the summer of 2010 we initiated the ALPhA Immersion Program, a three-day short course where instructors visit a lab, do one or more of the local experiments (home-built or commercial) with the local instructor, and learn the experiments well enough to incorporate them into their own programs. These immersions were very well received, with attendees filling up all available slots. In this talk I will describe ALPhA and the Immersions Program and solicit input from the broader community.

  15. Advances in fast-atom-bombardment mass spectroscopy

    SciTech Connect

    Hemling, M.E.

    1986-01-01

    A comparison of fast atom bombardment and field desorption mass spectrometry was made to determine relative sensitivity and applicability. A series of glycosphingolipids and a series of protected oligonucleotides of known structure were analyzed to ascertain the potential utility of fast atom bombardment mass spectrometry in the structural elucidation of novel compounds in these classes. Negative ion mass markers were also developed. Fast atom bombardment was found to be one-to-two orders of magnitude more sensitive than field desorption based on the analysis of a limited number of compounds from several classes. Superior sensitivity was not universal and field desorption was clearly better in certain cases. In the negative ion mode in particular, fast atom bombardment was found to be a useful tool for the determination of the primary structure of glycosphingolipids and oligonucleotides. Carbohydrate sequence and branching information, and a fatty acid and lipid base composition were readily obtained from the mass spectra of glycosphingolipids while bidirectional nucleotide sequence, nucleotide base, and protecting group assignments were obtained for oligonucleotides. Based on this knowledge, a tentative structure of a human peripheral nervous system glycosphingolipid implicated in certain cases of disorders such as amyotrophic lateral sclerosis, Lou Gehrig's Disease, was proposed. Suitable negative ion mass markers were found in dispersions of poly(ethylene) and poly(propylene)glycols in a triethylenetetramine matrix, a matrix which also proved useful in the analysis of glycosphingolipids. These polyglycol dispersions provided ions for calibration to 2300 daltons.

  16. Chapter 1: Recent Advances in Solar Physics

    NASA Astrophysics Data System (ADS)

    Dwivedi, B. N.

    2008-10-01

    For millennia, the Sun (and the universe) has been viewed in the visual light. As the bestower of light and life, the ancients made God out of the Sun. With the Babylonians, or with the multiple origins with the Chinese, Egyptians and Indians, quoting the Rig Veda:"All that exists was born from Sūrya, the God of gods.", we have come a long way to understanding the Sun. In the early seventeenth century, however, Galileo showed that the Sun was not an immaculate object. Thus began our scientific interests in our nearest stellar neighbour, the Sun (cf., Figure 1.1.), with its sunspots and the related solar activity. The observations of the Sun and their interpretations are of universal importance for at least two reasons: First, the Sun is the source of energy for the entire planetary system and all aspects of our life have direct impact on what happens on the Sun; and second, the Sun's proximity makes it unique among the billions of stars in the sky of which we can resolve its surface features and study physical processes at work...

  17. BOOK REVIEW: Astrophysics (Advanced Physics Readers)

    NASA Astrophysics Data System (ADS)

    Kibble, Bob

    2000-07-01

    Here is a handy and attractive reader to support students on post-16 courses. It covers the astrophysics, astronomy and cosmology that are demanded at A-level and offers anyone interested in these fields an interesting and engaging reference book. The author and the production team deserve credit for producing such an attractive book. The content, in ten chapters, covers what one would expect at this level but it is how it is presented that struck me as the book's most powerful asset. Each chapter ends with a summary of key ideas. Line drawings are clear and convey enough information to make them more than illustrations - they are as valuable as the text in conveying information. Full colour is used throughout to enhance illustrations and tables and to lift key sections of the text. A number of colour photographs complement the material and serve to maintain interest and remind readers that astrophysics is about real observable phenomena. Included towards the end is a set of tables offering information on physical and astronomical data, mathematical techniques and constellation names and abbreviations. This last table puzzled me as to its value. There is a helpful bibliography which includes society contacts and a website related to the text. Perhaps my one regret is that there is no section where students are encouraged to actually do some real astronomy. Astrophysics is in danger of becoming an armchair and calculator interest. There are practical projects that students could undertake either for school assessment or for personal interest. Simple astrophotography to capture star trails, observe star colours and estimate apparent magnitudes is an example, as is a simple double-star search. There are dozens more. However, the author's style is friendly and collaborative. He befriends the reader as they journey together through the ideas. There are progress questions at the end of each chapter. Their style tends to be rather closed and they emphasize factual recall

  18. Prospects for advances in microwave atomic frequency standards

    NASA Technical Reports Server (NTRS)

    Walls, F. L.

    1979-01-01

    Traditional standards based on rubidium, cesium and hydrogen have been greatly refined over the past decade, such that the frequency stability of the current generation of devices is generally limited by those basic concepts on which they are based. Future advances in frequency stability will principally come from changes in the concepts on which the standards are based, and only secondarily from more careful engineering of the old concepts. The fundamental limitations in these standards are considered and the important conceptual and component advances which could have a major impact on future performance of these standards are indicated. A very promising new class of microwave standards based on ion storage techniques is examined.

  19. Underground atom gradiometer array for mass distribution monitoring and advanced geodesy

    NASA Astrophysics Data System (ADS)

    Canuel, B.

    2015-12-01

    After more than 20 years of fundamental research, atom interferometers have reached sensitivity and accuracy levels competing with or beating inertial sensors based on different technologies. Atom interferometers offer interesting applications in geophysics (gravimetry, gradiometry, Earth rotation rate measurements), inertial sensing (submarine or aircraft autonomous positioning), metrology (new definition of the kilogram) and fundamental physics (tests of the standard model, tests of general relativity). Atom interferometers already contributed significantly to fundamental physics by, for example, providing stringent constraints on quantum-electrodynamics through measurements of the hyperfine structure constant, testing the Equivalence Principle with cold atoms, or providing new measurements for the Newtonian gravitational constant. Cold atom sensors have moreover been established as key instruments in metrology for the new definition of the kilogram or through international comparisons of gravimeters. The field of atom interferometry (AI) is now entering a new phase where very high sensitivity levels must be demonstrated, in order to enlarge the potential applications outside atomic physics laboratories. These applications range from gravitational wave (GW) detection in the [0.1-10 Hz] frequency band to next generation ground and space-based Earth gravity field studies to precision gyroscopes and accelerometers. The Matter-wave laser Interferometric Gravitation Antenna (MIGA) presented here is a large-scale matter-wave sensor which will open new applications in geoscience and fundamental physics. The MIGA consortium gathers 18 expert French laboratories and companies in atomic physics, metrology, optics, geosciences and gravitational physics, with the aim to build a large-scale underground atom-interferometer instrument by 2018 and operate it till at least 2023. In this paper, we present the main objectives of the project, the status of the construction of the

  20. Turbulence and atomic physics in magnetically confined plasmas

    NASA Astrophysics Data System (ADS)

    Marandet, Y.; Bufferand, H.; Ciraolo, G.; Nace, N.; Serre, E.; Tamain, P.; Valentinuzzi, M.

    2017-03-01

    An overview of issues related to the interplay between atomic process and turbulence in the peripheral regions of magnetically confined fusion devices is presented. Both atomic processes and turbulence play key roles for fusion, but have most of the time been treated separately. The effects of fluctuations on the time averaged ionization balance, on the transport of neutral particles (atoms and molecules) are discussed, using stochastic models to generate fluctuations with statistically relevant properties. Then applications to optical diagnostics of turbulence, namely gas puff imaging and beam emission spectroscopy are discussed.

  1. Advances in low energy neutral atom imaging techniques

    SciTech Connect

    Scime, E.E.; Funsten, H.O.; McComas, D.J.; Moore, K.R. ); Gruntman, M. . Space Sciences Center)

    1993-01-01

    Recently proposed low energy neutral atom (LENA) imaging techniques use a collisional process to convert the low energy neutrals into ions before detection. At low energies, collisional processes limit the angular resolution and conversion efficiencies of these devices. However, if the intense ultraviolet light background can be suppressed, direct LENA detection is possible. We present results from a series of experiments designed to develop a novel filtering structure based on free-standing transmission gratings. If the grating period is sufficiently small, free standing transmission gratings can be employed to substantially polarize ultraviolet (UV) light in the wavelength range 300 [Angstrom] to 1500 [Angstrom]. If a second grating is placed behind the first grating with its axis of polarization oriented at a right angle to the first's, a substantial attenuation of UV radiation is achievable. ne neutrals will pass through the remaining open area of two gratings and be detected without UV background complications. We have obtained nominal 2000 [Angstrom] period (1000 [Angstrom] bars with 1000 [Angstrom] slits) free standing, gold transmission gratings and measured their UV and atomic transmission characteristics. The geometric factor of a LENA imager based on this technology is comparable to that of other proposed LENA imagers. In addition, this of imager does not distort the neutral trajectories, allowing for high angular resolution.

  2. 2004 Physics and Advanced Technologies In the News

    SciTech Connect

    Hazi, A

    2005-11-01

    Several outstanding research activities in the Physics and Advanced Technology Directorate in 2004 were featured in ''Science & Technology Review'', the monthly publication of the Lawrence Livermore National Laboratory. Reprints of those articles accompany this report. Here we summarize other science and technology highlights, as well as the awards and recognition received by members of the Directorate in 2004.

  3. 2005 Physics and Advanced Technologies in the News

    SciTech Connect

    Hazi, A U

    2006-12-19

    Several outstanding research activities in the Physics and Advanced Technologies Directorate in 2005 were featured in ''Science and Technology Review'', the monthly publication of Lawrence Livermore National Laboratory. Reprints of those articles accompany this report. Here we summarize other science and technology highlights, as well as the awards and recognition received by members of the Directorate in 2005. As part of the World Year of Physics commemorating the 100th anniversary of Einstein's ''miraculous year'', we also highlight ongoing physics research that would not be possible without Einstein's pioneering accomplishments.

  4. Ultimate statistical physics: fluorescence of a single atom

    NASA Astrophysics Data System (ADS)

    Pomeau, Yves; Le Berre, Martine; Ginibre, Jean

    2016-10-01

    We discuss the statistics of emission of photons by a single atom or ion illuminated by a laser beam at the frequency of quasi-resonance between two energy levels, a situation that corresponds to real experiments. We extend this to the case of two laser beams resonant with the energy differences between two excited levels and the ground state (three level atom in V-configuration). We use a novel approach to this type of problem by considering a Kolmogorov equation for the probability distribution of the atomic state, which takes into account first the deterministic evolution of this state under the effect of the incoming laser beam and second the random emission of photons during the spontaneous decay of the excited state(s) to the ground state. This approach yields solvable equations in the two level atom case. For the three level atom case we set the problem and clearly define its frame. The results obtained are valid in both opposite limits of rare and frequent spontaneous decay, compared to the period of the optical Rabi oscillations due to the interaction between resonant excitation and atomic levels. Our analysis gives access to various statistical properties of the fluorescence light, including one showing that its fluctuations in time are not invariants under time reversal. This result makes evident the fundamentally irreversible character of quantum measurements, represented here by the emission of photons of fluorescence.

  5. Pre-Service Physics Teachers' Ideas on Size, Visibility and Structure of the Atom

    ERIC Educational Resources Information Center

    Unlu, Pervin

    2010-01-01

    Understanding the atom gives the opportunity to both understand and conceptually unify the various domains of science, such as physics, chemistry, biology, astronomy and geology. Among these disciplines, physics teachers are expected to be particularly well educated in this topic. It is important that pre-service physics teachers know what sort of…

  6. Inelastic processes in atomic, molecular and chemical physics (in honour of Andrey K. Belyaev)

    NASA Astrophysics Data System (ADS)

    Barklem, Paul S.; Tscherbul, Timur V.

    2015-11-01

    This Special Issue is dedicated to Professor Andrey K. Belyaev, on the occasion of his 60th birthday and in celebration of his productive career in theoretical atomic, molecular, and chemical physics. It brings together 12 research studies of Inelastic Processes in Atomic, Molecular and Chemical Physics, a research area where Andrey himself made significant contributions. Inelastic processes are central to many different areas of physics, including atmospheric physics, astrophysics, and plasma physics to name a few, as well as in related technological applications such as lasers and fusion reactors. Quantitative understanding of the mechanisms of inelastic processes in atoms and molecules is therefore a problem of fundamental importance in physics, astrophysics, and chemistry. It is precisely this challenging problem that Andrey's research addresses using a broad arsenal of theoretical tools and techniques.

  7. "Reaction Microscopes": The "Cloud Chambers" of Atomic and Molecular Physics

    NASA Astrophysics Data System (ADS)

    Ullrich, Joachim

    2004-09-01

    Reaction-Microscopes, developed 10 years ago in order to investigate fast ion-atom collisions [1], allow to determine the complete vector momenta of several electrons and ions emerging as a result of the fragmentation of single atoms, molecules or clusters interacting with electrons, ions, single photons or intense laser pulses. Thus, the complete final-state many-particle wave function in momentum space becomes observable for single and multiple ionisation of atoms as well as for the dissociation of molecules [2]. In the talk the working principle of these machines will be described. Illustrative examples will be given demonstrating the ability of the method to identify the ``mechanisms'' of single and multiple ionisation for electron and ion impact. Its potential for the investigation of single photon as well as of intense laser-pulse induced fragmentation will be highlighted. Future possibilities to investigate ultra-low-energy electron atom or molecule collisions, laser assisted ionisation, using few-cycle phase controlled laser pulses or future free-electron lasers are envisaged. [1] R. Moshammer et al., Phys. Rev. Lett. 73 (1994) 3371 [2] J. Ullrich et al., Rep. Prog. Phys. 66 (2003) 1463

  8. Images of Atoms.

    ERIC Educational Resources Information Center

    Wright, Tony

    2003-01-01

    Recommends using a simple image, such as the fuzzy atom ball to help students develop a useful understanding of the molecular world. Explains that the image helps students easily grasp ideas about atoms and molecules and leads naturally to more advanced ideas of atomic structure, chemical bonding, and quantum physics. (Author/NB)

  9. Upper Secondary Students' Understanding of the Basic Physical Interactions in Analogous Atomic and Solar Systems

    ERIC Educational Resources Information Center

    Taber, Keith S.

    2013-01-01

    Comparing the atom to a "tiny solar system" is a common teaching analogy, and the extent to which learners saw the systems as analogous was investigated. English upper secondary students were asked parallel questions about the physical interactions between the components of a simple atomic system and a simple solar system to investigate…

  10. Request for Support for the Conference on Super Intense Laser Atom Physics

    SciTech Connect

    Todd Ditmire

    2004-10-21

    The Conference on Super Intense Laser Atom Physics (SILAP) was held in November 2003 in Dallas, Texas. The venue for the meeting was South Fork Ranch in the outskirts of Dallas. The topics of the meeting included high harmonic generation and attosecond pulse generation, strong field interactions with molecules and clusters, particle acceleration, and relativistic laser atom interactions.

  11. ATOMIC PHYSICS PROCESSES IMPORTANT TO THE UNDERSTANDING OF THE SCRAPE-OFF LAYER OF TOKAMAKS

    SciTech Connect

    WEST, W.P.; GOLDSMITH,; B. EVANS,T.E.; OLSON, R.J.

    2002-05-01

    The region between the well-confined plasma and the vessel walls of a magnetic confinement fusion research device, the scrape-off layer (SOL), is typically rich in atomic and molecular physics processes. The most advanced magnetic confinement device, the magnetically diverted tokamak, uses a magnetic separatrix to isolate the confinement zone (closed flux surfaces) from the edge plasma (open field lines). Over most of their length the open field lines run parallel to the separatrix, forming a thin magnetic barrier with the nearby vessel walls. In a poloidally-localized region, the open field lines are directed away from the separatrix and into the divertor, a region spatially separated from the separatrix where intense plasma wall interaction can occur relatively safely. Recent data from several tokamaks indicate that particle transport across the field lines of the SOL can be somewhat faster than previously thought. In these cases, the rate at which particles reach the vessel wall is comparable to the rate to the divertor from parallel transport. The SOL can be thin enough that the recycling neutrals and sputtered impurities from the wall may refuel or contaminate the confinement zone more efficiently than divertor plasma wall interaction. Just inside the SOL is a confinement barrier that produces a sharp pedestal in plasma density and temperature. Understanding neutral transport through the SOL and into the pedestal is key to understanding particle balance and particle and impurity exhaust. The SOL plasma is sufficiently hot and dense to excite and ionize neutrals. Ion and neutral temperatures are high enough that charge exchange between the neutrals and fuel and impurity ions is fast. Excitation of neutrals can be fast enough to lead to nonlinear behavior in charge exchange and ionization processes. In this paper the detailed atomic physics important to the understanding of the neutral transport through the SOL will be discussed.

  12. Research in atomic and applied physics using a 6-GeV synchrotron source

    SciTech Connect

    Jones, K.W.

    1985-12-01

    The Division of Atomic and Applied Physics in the Department of Applied Science at Brookhaven National Laboratory conducts a broad program of research using ion beams and synchrotron radiation for experiments in atomic physics and nuclear analytical techniques and applications. Many of the experiments would benefit greatly from the use of high energy, high intensity photon beams from a 6-GeV synchrotron source. A survey of some of the specific scientific possibilities is presented.

  13. System studies for quasi-steady-state advanced physics tokamak

    SciTech Connect

    Reid, R.L.; Peng, Y.K.M.

    1983-11-01

    Parametric studies were conducted using the Fusion Engineering Design Center (FEDC) Tokamak Systems Code to investigate the impact of veriation in physics parameters and technology limits on the performance and cost of a low q/sub psi/, high beta, quasi-steady-state tokamak for the purpose of fusion engineering experimentation. The features and characteristics chosen from each study were embodied into a single Advanced Physics Tokamak design for which a self-consistent set of parameters was generated and a value of capital cost was estimated.

  14. Learning Pathways in High-School Level Quantum Atomic Physics.

    ERIC Educational Resources Information Center

    Niedderer, Hans; Petri, Juergen

    Investigations of changes in conceptions during physics instruction are the logical and necessary steps to follow successful international research on students' preinstructional conceptions. The theoretical perspective integrates currently available frameworks of cognition, cognitive states, and cognitive processes in physics. Particular emphasis…

  15. A New Computerised Advanced Theory of Mind Measure for Children with Asperger Syndrome: The ATOMIC

    ERIC Educational Resources Information Center

    Beaumont, Renae B.; Sofronoff, Kate

    2008-01-01

    This study examined the ability of children with Asperger Syndrome (AS) to attribute mental states to characters in a new computerised, advanced theory of mind measure: The Animated Theory of Mind Inventory for Children (ATOMIC). Results showed that children with AS matched on IQ, verbal comprehension, age and gender performed equivalently on…

  16. Computational challenges in atomic, molecular and optical physics.

    PubMed

    Taylor, Kenneth T

    2002-06-15

    Six challenges are discussed. These are the laser-driven helium atom; the laser-driven hydrogen molecule and hydrogen molecular ion; electron scattering (with ionization) from one-electron atoms; the vibrational and rotational structure of molecules such as H(3)(+) and water at their dissociation limits; laser-heated clusters; and quantum degeneracy and Bose-Einstein condensation. The first four concern fundamental few-body systems where use of high-performance computing (HPC) is currently making possible accurate modelling from first principles. This leads to reliable predictions and support for laboratory experiment as well as true understanding of the dynamics. Important aspects of these challenges addressable only via a terascale facility are set out. Such a facility makes the last two challenges in the above list meaningfully accessible for the first time, and the scientific interest together with the prospective role for HPC in these is emphasized.

  17. Physics of the missing atoms: technetium and promethium

    SciTech Connect

    Aspden, H.

    1987-05-01

    Technetium (Z = 43) and promethium (Z = 61) are by far the least abundant of all atoms below the radioactive elements (Z = 84 onwards). Their scarcity confirms theoretical predictions emerging from a theory of the photon derived from synchronous lattice electrodynamics. This theory has given precise theoretical values for the fine-structure constant and the constant of gravitation G and is now shown in this paper to indicate resonant interactions between the vacuum lattice oscillations and technetium and promethium. In the case of promethium there is strong reason for believing that this atom can assume supergravitational or antigravitational properties, accounting for its scarcity. This paper not only adds support to the earlier theoretical work on the photon and gravitation, but suggests a research route that might lead to new technology based on controlled interactions with gravity fields.

  18. Advanced Swimming, Phase II--Advanced Swimmer; Physical Education: 5551.48.

    ERIC Educational Resources Information Center

    Gutting, Dick

    GRADES OR AGES: Grades 7-12. SUBJECT MATTER: Advanced swimming. ORGANIZATION AND PHYSICAL APPEARANCE: The first two sections of the guides are devoted to course guidelines, description, and broad goal statement. The next two sections list behavioral and skill objectives and course content. The fifth section presents learning activities and…

  19. The Physics of Spin-Polarized Atomic Vapors.

    DTIC Science & Technology

    1985-01-01

    formula (82) (Ref. II). shift methods. In this paper we present the basic theory of spin ex- lower third-body pressures. Essentially the same relaxa- change...polarization during the 129Xe relaxa- The voltages on the capacitors are tion transient the left side of R,, in Fig. 17 is essentially "FM F) at ground...exchange is described by non-linear rate equa- tions. The nonlinearity is essential if one is to account for the spin polarization of both atoms which are

  20. Application of Group Theory to Some Problems in Atomic Physics.

    NASA Astrophysics Data System (ADS)

    Suskin, Mark Albert

    This work comprises three problems, each of which lends itself to investigation via the theory of groups and group representations. The first problem is to complete a set of operators used in the fitting of atomic energy levels of atoms whose ground configuration is f ^ 3. The role of group theory in the labelling of these operators and in their construction is explained. Values of parameters associated with a subset of the operators are also calculated via their group labels. The second problem is to explain the term inversion that occurs between states of the configuration of two equivalent electrons and certain of the states of the half-filled shell. This leads to generalizations that make it possible to investigate correspondences between matrix elements of effective operators taken between states of other configurations besides the two mentioned. This is made possible through the notion of quasispin. The third problem is the construction of recoupling coefficients for groups other than SO(3). Questions of phase convention and Kronecker-product multiplicities are taken up. Several methods of calculation are given and their relative advantages discussed. Tables of values of the calculated 6-j symbols are provided.

  1. PREFACE: 8th Asian International Seminar on Atomic and Molecular Physics (AISAMP)

    NASA Astrophysics Data System (ADS)

    Williams, Jim F.; Buckman, Steve; Bieske, Evan J.

    2009-09-01

    These proceedings arose from the 8th Asian International Seminar on Atomic and Molecular Physics (AISAMP) which was held at the University of Western Australia 24-28 November 2008. The history of AISAMP (Takayanagi and Matsuzawa 2002) recognizes its origin from the Japan-China meeting of 1985, and the first use of the name 'The First Asian International Seminar on Atomic and Molecular Physics (AISAMP)' in 1992. The initial attendees, Japan and China, were joined subsequently by scientists from Korea, Taiwan, India, Australia and recently by Malaysia, Thailand, Vietnam, Turkey Iran, UK and USA. The main purpose of the biennial AISAMP series is to create a wide forum for exchanging ideas and information among atomic and molecular scientists and to promote international collaboration. The scope of the AISAMP8 meeting included pure, strategic and applied research involving atomic and molecular structure and processes in all forms of matter and antimatter. For 2008 the AISAMP conference incorporated the Australian Atomic and Molecular Physics and Quantum Chemistry meeting. The topics for AISAMP8 embraced themes from earlier AISAMP meetings and reflected new interests, in atomic and molecular structures, spectroscopy and collisions; atomic and molecular physics with laser or synchrotron radiation; quantum information processing using atoms and molecules; atoms and molecules in surface physics, nanotechnology, biophysics, atmospheric physics and other interdisciplinary studies. The implementation of the AISAMP themes, as well as the international representation of research interests, is indicated both in the contents list of these published manuscripts as well as in the program for the meeting. Altogether, 184 presentations were made at the 8th AISAMP, including Invited Talks and Contributed Poster Presentations, of which 60 appear in the present Proceedings after review by expert referees in accordance with the usual practice of Journal of Physics: Conference Series of

  2. How Novel Algorithms and Access to High Performance Computing Platforms are Enabling Scientific Progress in Atomic and Molecular Physics

    NASA Astrophysics Data System (ADS)

    Schneider, Barry I.

    2016-10-01

    Over the past 40 years there has been remarkable progress in the quantitative treatment of complex many-body problems in atomic and molecular physics (AMP). This has happened as a consequence of the development of new and powerful numerical methods, translating these algorithms into practical software and the associated evolution of powerful computing platforms ranging from desktops to high performance computational instruments capable of massively parallel computation. We are taking the opportunity afforded by this CCP2015 to review computational progress in scattering theory and the interaction of strong electromagnetic fields with atomic and molecular systems from the early 1960’s until the present time to show how these advances have revealed a remarkable array of interesting and in many cases unexpected features. The article is by no means complete and certainly reflects the views and experiences of the author.

  3. Nuclear physics (of the cell, not the atom)

    PubMed Central

    Pederson, Thoru; Marko, John F.

    2014-01-01

    The nucleus is physically distinct from the cytoplasm in ways that suggest new ideas and approaches for interrogating the operation of this organelle. Chemical bond formation and breakage underlie the lives of cells, but as this special issue of Molecular Biology of the Cell attests, the nonchemical aspects of cell nuclei present a new frontier to biologists and biophysicists. PMID:25368422

  4. Project Physics Teacher Guide 5, Models of the Atom.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    Teaching procedures of Project Physics Unit 5 are presented to help teachers make effective use of learning materials. Unit contents are discussed in connection with teaching aid lists, multi-media schedules, schedule blocks, and resource charts. Brief summaries are made for transparencies, 16mm films, and reader articles. Included is information…

  5. Nuclear physics (of the cell, not the atom).

    PubMed

    Pederson, Thoru; Marko, John F

    2014-11-05

    The nucleus is physically distinct from the cytoplasm in ways that suggest new ideas and approaches for interrogating the operation of this organelle. Chemical bond formation and breakage underlie the lives of cells, but as this special issue of Molecular Biology of the Cell attests, the nonchemical aspects of cell nuclei present a new frontier to biologists and biophysicists.

  6. Physical mechanisms for atomization of a jet spray

    SciTech Connect

    Bower, G.; Chang, S.K.; Corradini, M.L.; El-Beshbeeshy, M.; Martin, J.K.; Krueger, J.

    1988-01-01

    Because combustion in direct injection engines is strongly influenced by the details of the fuel spray in thes engines, the authors have begun a broad research effort of jet breakup experiments and modelling of these high pressure sprays. The main objective of this effort is to better understand fuel injection from the study of the spray-jet breakup process and the associated fuel-oxidant mixing. The focus of this paper is the development of specific models for atomization of the spray-jet. These models are then compared to each other and to preliminary data from the spray-jet breakup experiments. Initial results indicate that KIVA with this proposed spray model shows good agreement with low pressure data (69 MPa) but underestimates spray penetration for higher pressures (104 MPa).

  7. Visualising reacting single atoms under controlled conditions: Advances in atomic resolution in situ Environmental (Scanning) Transmission Electron Microscopy (E(S)TEM)

    NASA Astrophysics Data System (ADS)

    Boyes, Edward D.; Gai, Pratibha L.

    2014-02-01

    Advances in atomic resolution Environmental (Scanning) Transmission Electron Microscopy (E(S)TEM) for probing gas-solid catalyst reactions in situ at the atomic level under controlled reaction conditions of gas environment and temperature are described. The recent development of the ESTEM extends the capability of the ETEM by providing the direct visualisation of single atoms and the atomic structure of selected solid state heterogeneous catalysts in their working states in real-time. Atomic resolution E(S)TEM provides a deeper understanding of the dynamic atomic processes at the surface of solids and their mechanisms of operation. The benefits of atomic resolution-E(S)TEM to science and technology include new knowledge leading to improved technological processes with substantial economic benefits, improved healthcare, reductions in energy needs and the management of environmental waste generation. xml:lang="fr"

  8. Physics of Optically Pumped Alkali-Metal Atoms

    DTIC Science & Technology

    2013-04-14

    collision broadening and will be almost completely determined by hyperfine structure, natural radiative broadening and Doppler broadening . 3 When pumped by...supported research, and will be an great advantage for work on greenhouse physics. Of particular interest is how collisions of CO2 molecules with the...nitrogen and oxygen molecules of the air affect the way CO2 absorbs and emits radiation. Incorrect modeling of collisional line broadening is one of

  9. Resource Letter ANP-1: Advances in Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Goodman, Maury C.

    2016-12-01

    Three of the twelve fundamental fermions in particle physics are neutrinos. It was long thought that neutrinos might be massless, but we now know through the phenomenon of neutrino oscillations that neutrinos have mass. This resource letter will cover the history of the growth in our knowledge about neutrinos since they were first proposed in the 1930s, and also covers some up the upcoming experiments which will further our understanding of neutrino properties. Results from experiments are described that use various sources of neutrinos including nuclear reactors, cosmic rays, accelerators, and supernovae. In this resource letter, the resources that can be used to trace the past, present, and anticipated future advances in neutrino physics are reviewed.

  10. Extending synchrotron-based atomic physics experiments into the hard X-ray region

    SciTech Connect

    LeBrun, T.

    1996-12-31

    The high-brightness, hard x-ray beams available from third-generation synchrotron sources are opening new opportunities to study the deepest inner shells of atoms, an area where little work has been done and phenomena not observed in less tightly bound inner-shells are manifested. In addition scattering processes which are weak at lower energies become important, providing another tool to investigate atomic structure as well as an opportunity to study photon/atom interactions beyond photoabsorption. In this contribution the authors discuss some of the issues related to extending synchrotron-based atomic physics experiments into the hard x-ray region from the physical and the experimental point of view. They close with a discussion of a technique, resonant Raman scattering, that may prove invaluable in determining the spectra of the very highly-excited states resulting from the excitation of deep inner shells.

  11. Identifying and addressing specific student difficulties in advanced thermal physics

    NASA Astrophysics Data System (ADS)

    Smith, Trevor I.

    As part of an ongoing multi-university research study on student understanding of concepts in thermal physics at the upper division, I identified several student difficulties with topics related to heat engines (especially the Carnot cycle), as well as difficulties related to the Boltzmann factor. In an effort to address these difficulties, I developed two guided-inquiry worksheet activities (a.k.a. tutorials) for use in advanced undergraduate thermal physics courses. Both tutorials seek to improve student understanding of the utility and physical background of a particular mathematical expression. One tutorial focuses on a derivation of Carnot's theorem regarding the limit on thermodynamic efficiency, starting from the Second Law of Thermodynamics. The other tutorial helps students gain an appreciation for the origin of the Boltzmann factor and when it is applicable; focusing on the physical justification of its mathematical derivation, with emphasis on the connections between probability, multiplicity, entropy, and energy. Student understanding of the use and physical implications of Carnot's theorem and the Boltzmann factor was assessed using written surveys both before and after tutorial instruction within the advanced thermal physics courses at the University of Maine and at other institutions. Classroom tutorial sessions at the University of Maine were videotaped to allow in-depth scrutiny of student successes and failures following tutorial prompts. I also interviewed students on various topics related to the Boltzmann factor to gain a more complete picture of their understanding and inform tutorial revisions. Results from several implementations of my tutorials at the University of Maine indicate that students did not have a robust understanding of these physical principles after lectures alone, and that they gain a better understanding of relevant topics after tutorial instruction; Fisher's exact tests yield statistically significant improvement at the

  12. PROBING THE PHYSICAL CONDITIONS OF ATOMIC GAS AT HIGH REDSHIFT

    SciTech Connect

    Neeleman, Marcel; Wolfe, Arthur M.; Prochaska, J. Xavier

    2015-02-10

    A new method is used to measure the physical conditions of the gas in damped Lyα systems (DLAs). Using high-resolution absorption spectra of a sample of 80 DLAs, we are able to measure the ratio of the upper and lower fine-structure levels of the ground state of C{sup +} and Si{sup +}. These ratios are determined solely by the physical conditions of the gas. We explore the allowed physical parameter space using a Monte Carlo Markov chain method to constrain simultaneously the temperature, neutral hydrogen density, and electron density of each DLA. The results indicate that at least 5% of all DLAs have the bulk of their gas in a dense, cold phase with typical densities of ∼100 cm{sup –3} and temperatures below 500 K. We further find that the typical pressure of DLAs in our sample is log (P/k{sub B} ) = 3.4 (K cm{sup –3}), which is comparable to the pressure of the local interstellar medium (ISM), and that the components containing the bulk of the neutral gas can be quite small with absorption sizes as small as a few parsecs. We show that the majority of the systems are consistent with having densities significantly higher than expected for a purely canonical warm neutral medium, indicating that significant quantities of dense gas (i.e., n {sub H} > 0.1 cm{sup –3}) are required to match observations. Finally, we identify eight systems with positive detections of Si II*. These systems have pressures (P/k{sub B} ) in excess of 20,000 K cm{sup –3}, which suggest that these systems tag a highly turbulent ISM in young, star-forming galaxies.

  13. Clock Technology Development for the Laser Cooling and Atomic Physics (LCAP) Program

    NASA Technical Reports Server (NTRS)

    Klipstein, W. M.; Thompson, R. J.; Seidel, D. J.; Kohel, J.; Maleki, L.

    1998-01-01

    The Time and Frequency Sciences and Technology Group at Jet Propulsion Laboratory (JPL) has developed a laser cooling capability for flight and has been selected by NASA to support the Laser-Cooling and Atomic Physics (LCAP) program. Current work in the group includes design and development for tee two laser-cooled atomic clock experiments which have been selected for flight on the International Space Station.

  14. Otto Stern (1888-1969): The founding father of experimental atomic physics

    NASA Astrophysics Data System (ADS)

    Toennies, J. P.; Schmidt-Böcking, H.; Friedrich, B.; Lower, J. C. A.

    2011-12-01

    We review the work and life of Otto Stern who developed the molecular beam technique and with its aid laid the foundations of experimental atomic physics. Among the key results of his research are: the experimental determination of the Maxwell-Boltzmann distribution of molecular velocities (1920), experimental demonstration of space quantization of angular momentum (1922), diffraction of matter waves comprised of atoms and molecules by crystals (1931) and the determination of the magnetic dipole moments of the proton and deuteron (1933).

  15. Computation of Free-Free Transitions in Atomic Physics: Foundations

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Sucher, J.

    2003-01-01

    The amplitude T for "free-free" processes, such as bremsstrahlung or photo- absorption by an electron in the continuum in the presence of an external field, is usually written as the matrix element of the radiation operator taken between two continuum states. However, unlike the case when at least one of the states is bound, as in radiative transitions, electron capture, or the photo-effect, this expression contains an unphysical term, proportional to a delta-function and is not really the physical amplitude Tphys. This continues to be true for both the velocity and length form of the dipole approximation to the amplitude T. We first give an a priori definition of Tphys in terms of the scattering parts of the continuum functions, which has an obvious interpretation in terms of time-ordered diagrams. We then show that when the formal amplitude is modified by a long- distance cutoff, the modified form approaches Tphys as the cutoff is removed. The modified form then serves as a basis for the definition of a physical velocity dipole amplitude and this in turn leads to an equivalent length form of the dipole amplitude. This exercise provides a clear theoretical basis for many extant calculations in which cutoff factors are introduces somewhat ad hoc, as needed.

  16. New Phenomena in Physics Related with Single-Atom Electron Sources

    NASA Astrophysics Data System (ADS)

    Akamine, Yuta; Fujiwara, Kazuto; Cho, Bokulae; Oshima, Chuhei

    We have reviewed new phenomena in physics related with development of single-atom electron sources. A collimated electron beam was emitted from the single-atom situated at the top of the nano-pyramids. The following three topics have been discussed. (1) High brightness of electron beam: High-density electrons come out of the source, and overlapping of wave functions presumably produces new phenomena including anti-bunching of electrons in vacuum. Energy spectra showed characteristic features of single-atom electron sources; additional shoulders appeared in the normal spectra. 3) Stable electron emission originates from the field evaporation.

  17. Advanced physical assessment skills: implementation of a module.

    PubMed

    Aldridge-Bent, Sharon

    2011-02-01

    This article aims to explore and examine advanced physical assessment skills and the role of the district nurse. It will particularly highlight district nurses' perceptions of how they may implement skills learnt on a new module introduced into the Community Health Care Nursing degree at a university in London. Physical assessment skills have traditionally been viewed as part of a doctor's role; however, with the advancement of nursing roles, it is argued that it has become a key nursing skill. As Government policy continues to expect health professionals to keep patients in the community who have complex health and social care needs, the role of the district nurse presents as 'best placed' to take on this challenge (Department of Health (DH), 2005a; 2005b). Evaluation of the district nurses' perceptions of their practice is shared here, highlighting some of the challenges that they face. The article will address the complexity of developing a curriculum in response to the DH initiatives and the importance of listening to students on courses.

  18. Coal surface control for advanced physical fine coal cleaning technologies

    SciTech Connect

    Morsi, B.I.; Chiang, S.H.; Sharkey, A.; Blachere, J.; Klinzing, G.; Araujo, G.; Cheng, Y.S.; Gray, R.; Streeter, R.; Bi, H.; Campbell, P.; Chiarlli, P.; Ciocco, M.; Hittle, L.; Kim, S.; Kim, Y.; Perez, L.; Venkatadri, R.

    1992-01-01

    This final report presents the research work carried out on the Coal Surface Control for Advanced Physical Fine Coal Cleaning Technologies project, sponsored by the US Department of Energy, Pittsburgh Energy Technology Center (DOE/PETC). The project was to support the engineering development of the selective agglomeration technology in order to reduce the sulfur content of US coals for controlling SO[sub 2] emissions (i.e., acid rain precursors). The overall effort was a part of the DOE/PETCs Acid Rain Control Initiative (ARCI). The overall objective of the project is to develop techniques for coal surface control prior to the advanced physical fine coal cleaning process of selective agglomeration in order to achieve 85% pyrite sulfur rejection at an energy recovery greater than 85% based on run-of-mine coal. The surface control is meant to encompass surface modification during grinding and laboratory beneficiation testing. The project includes the following tasks: Project planning; methods for analysis of samples; development of standard beneficiation test; grinding studies; modification of particle surface; and exploratory R D and support. The coal samples used in this project include three base coals, Upper Freeport - Indiana County, PA, Pittsburgh NO. 8 - Belmont County, OH, and Illinois No. 6 - Randolph County, IL, and three additional coals, Upper Freeport - Grant County- WV, Kentucky No. 9 Hopkins County, KY, and Wyodak - Campbell County, WY. A total of 149 drums of coal were received.

  19. ATOMIC AND MOLECULAR PHYSICS: Modelling of a DNA packaging motor

    NASA Astrophysics Data System (ADS)

    Qian, Jun; Xie, Ping; Xue, Xiao-Guang; Wang, Peng-Ye

    2009-11-01

    During the assembly of many viruses, a powerful molecular motor packages the genome into a preassembled capsid. The Bacillus subtilis phage phi29 is an excellent model system to investigate the DNA packaging mechanism because of its highly efficient in vitro DNA packaging activity and the development of a single-molecule packaging assay. Here we make use of structural and biochemical experimental data to build a physical model of DNA packaging by the phi29 DNA packaging motor. Based on the model, various dynamic behaviours such as the packaging rate, pause frequency and slip frequency under different ATP concentrations, ADP concentrations, external loads as well as capsid fillings are studied by using Monte Carlo simulation. Good agreement is obtained between the simulated and available experimental results. Moreover, we make testable predictions that should guide future experiments related to motor function.

  20. V. S. Lebedev and I. L. Beigman, Physics of Highly Excited Atoms and Ions

    NASA Astrophysics Data System (ADS)

    Mewe, R.

    1999-07-01

    This book contains a comprehensive description of the basic principles of the theoretical spectroscopy and experimental spectroscopic diagnostics of Rydberg atoms and ions, i.e., atoms in highly excited states with a very large principal quantum number (n≫1). Rydberg atoms are characterized by a number of peculiar physical properties as compared to atoms in the ground or a low excited state. They have a very small ionization potential (∝1/n2), the highly excited electron has a small orbital velocity (∝1/n), the radius (∝n2) is very large, the excited electron has a long orbital period (∝n3), and the radiation lifetime is very long (∝n3-5). At the same time the R. atom is very sensitive to perturbations from external fields in collisions with charged and neutral targets. In recent years, R. atoms have been observed in laboratory and cosmic conditions for n up to ˜1000, which means that the size amounts to about 0.1 mm, ˜106 times that of an atom in the ground state. The scope of this monograph is to familiarize the reader with today's approaches and methods for describing isolated R. atoms and ions, radiative transitions between highly excited states, and photoionization and photorecombination processes. The authors present a number of efficient methods for describing the structure and properties of R. atoms and calculating processes of collisions with neutral and charged particles as well as spectral-line broadening and shift of Rydberg atomic series in gases, cool and hot plasmas in laboratories and in astrophysical sources. Particular attention is paid to a comparison of theoretical results with available experimental data. The book contains 9 chapters. Chapter 1 gives an introduction to the basic properties of R. atoms (ions), Chapter 2 is devoted to an account of general methods describing an isolated Rydberg atom. Chapter 3 is focussed on the recent achievements in calculations of form factors and dipole matrix elements of different types of

  1. Climate Solutions based on advanced scientific discoveries of Allatra physics

    NASA Astrophysics Data System (ADS)

    Vershigora, Valery

    2016-01-01

    Global climate change is one of the most important international problems of the 21st century. The overall rapid increase in the dynamics of cataclysms, which have been observed in recent decades, is particularly alarming. Howdo modern scientists predict the occurrence of certain events? In meteorology, unusually powerful cumulonimbus clouds are one of the main conditions for the emergence of a tornado. The former, in their turn, are formed during the invasion of cold air on the overheated land surface. The satellite captures the cloud front, and, based on these pictures, scientists make assumptions about the possibility of occurrence of the respective natural phenomena. In fact, mankind visually observes and draws conclusions about the consequences of the physical phenomena which have already taken place in the invisible world, so the conclusions of scientists are assumptions by their nature, rather than precise knowledge of the causes of theorigin of these phenomena in the physics of microcosm. The latest research in the field of the particle physics and neutrino astrophysics, which was conducted by a working team of scientists of ALLATRA International Public Movement (hereinafter ALLATRA SCIENCE group), offers increased opportunities for advanced fundamental and applied research in climatic engineering.

  2. Advanced Ground Systems Maintenance Physics Models For Diagnostics Project

    NASA Technical Reports Server (NTRS)

    Perotti, Jose M.

    2015-01-01

    The project will use high-fidelity physics models and simulations to simulate real-time operations of cryogenic and systems and calculate the status/health of the systems. The project enables the delivery of system health advisories to ground system operators. The capability will also be used to conduct planning and analysis of cryogenic system operations. This project will develop and implement high-fidelity physics-based modeling techniques tosimulate the real-time operation of cryogenics and other fluids systems and, when compared to thereal-time operation of the actual systems, provide assessment of their state. Physics-modelcalculated measurements (called “pseudo-sensors”) will be compared to the system real-timedata. Comparison results will be utilized to provide systems operators with enhanced monitoring ofsystems' health and status, identify off-nominal trends and diagnose system/component failures.This capability can also be used to conduct planning and analysis of cryogenics and other fluidsystems designs. This capability will be interfaced with the ground operations command andcontrol system as a part of the Advanced Ground Systems Maintenance (AGSM) project to helpassure system availability and mission success. The initial capability will be developed for theLiquid Oxygen (LO2) ground loading systems.

  3. Clock Technology Development in the Laser Cooling and Atomic Physics (LCAP) Program

    NASA Technical Reports Server (NTRS)

    Seidel, Dave; Thompson, R. J.; Klipstein, W. M.; Kohel, J.; Maleki, L.

    2000-01-01

    This paper presents the Laser Cooling and Atomic Physics (LCAP) program. It focuses on clock technology development. The topics include: 1) Overview of LCAP Flight Projects; 2) Space Clock 101; 3) Physics with Clocks in microgravity; 4) Space Clock Challenges; 5) LCAP Timeline; 6) International Space Station (ISS) Science Platforms; 7) ISS Express Rack; 8) Space Qualification of Components; 9) Laser Configuration; 10) Clock Rate Comparisons: GPS Carrier Phase Frequency Transfer; and 11) ISS Model Views. This paper is presented in viewgraph form.

  4. Recent Advances and Cross-Century Outlooks in Physics, Interplay between Theory and Experiment.

    NASA Astrophysics Data System (ADS)

    Chen, Pisin; Wong, Cheuk-Yin

    The Table of Contents for the book is as follows: * Preface * Interdisciplinary Topics * SUPERSYMMETRY * Supersymmetry, Noncommutative Geometry and Ultimate Unification * Supersymmetry and Beam Dynamics * Brane World * Dynamical Symmetries in High-Temperature Superconductivity * BEAM, PLASMA, GRAVITATION, AND ASTRONOMY * Toroidal Akfvén Eigenmode Experiments in TFTR * Empirical Tests of the Relativistic Gravity: The Past, the Present and the Future * Radio Astronomy in Taiwan: (Personal) Highlights * PARTICLE AND NUCLEAR PHYSICS * Is There only Top Quark? Review of Top Results * Some Topics on Double Heavy Mesons: Heavy Quarkonia and Bc Meson * Softly Broken CP Symmetry * A Pilot Experiment with Reactor Neutrinos in Taiwan * The Composition of the Proton Spin * Recent Results from Thomas Jefferson National Accelerator Facility * SYNCHROTRON RADIATION AND ATOMIC PHYSICS * Synchrotron Radiation/Laser and Doubly-Excited Atoms * Multiply Excited States for Lithium * FRACTIONAL QUANTUM HALL EFFECT * An Introduction to Topological Orders and Edge Excitations in Quantum Hall States * Phases and Phase Transitions in the Quantum Hall Effect * Chiral Luttinger Liquids at the Fractional Quantum Hall Edge * HIGH-Tc SUPERCONDUCTOR PHYSICS * Two Energy Gaps in Cuprate Superconductors: Clues to the High-Tc Mechanism * Applications of High Temperature Superconductors * Magnetism and Superconductivity in Ru-Based Perovskites * Correlation between Crystal Symmetry, Weak Ferromagnetism and Superconductivity in Distorted T'-phase Cuprates * CHAOS * An Overview of Chaos * Chaotic Dynamics: Introduction and Recent Developments * Chaos in Accelerators * HIGHLIGHTS OF PHYSICS ADVANCES IN TAIWAN * Solving the X-Ray Phase Problem for omolecular Crystals by Multi-Wave X-Ray Interference * BOSE-EINSTEIN CONDENSATION * Bogoliubov Dispersion Relation and the Possibility of Superfluidity for Weakly-interacting Photons * Bose-Einstein Effects in High-Energy Physics * Physics without Borders

  5. PREFACE: 7th Asian International Seminar on Atomic and Molecular Physics

    NASA Astrophysics Data System (ADS)

    Deshmukh, Pranawa C.; Chakraborty, Purushottam; Williams, Jim F.

    2007-09-01

    These proceedings arose from the 7th Asian International Seminar on Atomic and Molecular Physics (AISAMP) which was held at the Indian Institute of Technology, Madras from 4-7 December 2006. The history of the AISAMP has been reviewed by Takayanagi http://www.physics.iitm.ac.in/~aisamp7/history.html. This international seminar/conference series grew out of the Japan-China meetings which were launched in 1985, the fourth of which was held in 1992 and carried a second title: The First Asian International Seminar on Atomic and Molecular Physics (AISAMP), thus providing a formal medium for scientists in this part of the world to report periodically and exchange their scientific thoughts. The founding nations of Japan and China were joined subsequently by Korea, Taiwan, India and Australia. The aims of the symposia included bringing together leading experts and students of atomic and molecular physics, the discussion of important problems, learning and sharing modern techniques and expanding the horizons of modern atomic and molecular physics. The fields of interest ranged from atomic and molecular structure and dynamics to photon, electron and positron scattering, to quantum information processing, the effects of symmetry and many body interactions, laser cooling, cold traps, electric and magnetic fields and to atomic and molecular physics with synchrotron radiation. Particular interest was evident in new techniques and the changes of the physical properties from atomic to condensed matter. Details of the 7th AISAMP, including the topics for the special sessions and the full programme, are available online at the conference website http://www.physics.iitm.ac.in/~aisamp7/. In total, 95 presentations were made at the 7th AISAMP, these included the Invited Talks and Contributed Poster Presentations, of which 52 appear in the present Proceedings after review by expert referees, refereed to the usual standard of the Institute of Physics journal: Journal of Physics B: Atomic

  6. Reflection on problem solving in introductory and advanced physics

    NASA Astrophysics Data System (ADS)

    Mason, Andrew J.

    Reflection is essential in order to learn from problem solving. This thesis explores issues related to how reflective students are and how we can improve their capacity for reflection on problem solving. We investigate how students naturally reflect in their physics courses about problem solving and evaluate strategies that may teach them reflection as an integral component of problem-solving. Problem categorization based upon similarity of solution is a strategy to help them reflect about the deep features of the problems related to the physics principles involved. We find that there is a large overlap between the introductory and graduate students in their ability to categorize. Moreover, introductory students in the calculus-based courses performed better categorization than those in the algebra-based courses even though the categorization task is conceptual. Other investigations involved exploring if reflection could be taught as a skill on individual and group levels. Explicit self-diagnosis in recitation investigated how effectively students could diagnose their own errors on difficult problems, how much scaffolding was necessary for this purpose, and how effective transfer was to other problems employing similar principles. Difficulty in applying physical principles and difference between the self-diagnosed and transfer problems affected performance. We concluded that a sustained intervention is required to learn effective problem-solving strategies. Another study involving reflection on problem solving with peers suggests that those who reflected with peers drew more diagrams and had a larger gain from the midterm to final exam. Another study in quantum mechanics involved giving common problems in midterm and final exams and suggested that advanced students do not automatically reflect on their mistakes. Interviews revealed that even advanced students often focus mostly on exams rather than learning and building a robust knowledge structure. A survey was

  7. Atomic physics with highly charged ions. Progress report, 15 September 1984-14 September 1985

    SciTech Connect

    Richard, P.

    1985-09-01

    Advances are reported in the two areas of primary research: low-energy ion-atom collisions using secondary ion recoil sources, SIRS, and high-energy ion-atom collisions using the tandem Van de Graaff accelerator beams. We have investigated the feasibility of accel-decel with a tandem plus superconducting LINAC with great success, and we have continued to work on the designs of a stand-alone CRYEBIS and a superconducting Nb split-ring resonator LINAC as an appropriate booster for the EN tandem.

  8. Do General Physics Textbooks Discuss Scientists' Ideas about Atomic Structure? A Case in Korea

    ERIC Educational Resources Information Center

    Niaz, Mansoor; Kwon, Sangwoon; Kim, Nahyun; Lee, Gyoungho

    2013-01-01

    Research in science education has recognized the importance of teaching atomic structure within a history and philosophy of science perspective. The objective of this study is to evaluate general physics textbooks published in Korea based on the eight criteria developed in previous research. The result of this study shows that Korean general…

  9. Insights into the physical chemistry of materials from advances in HAADF-STEM

    DOE PAGES

    Sohlberg, Karl; Pennycook, Timothy J.; Zhou, Wu; ...

    2014-11-13

    The observation that, ‘‘New tools lead to new science’’[P. S. Weiss, ACS Nano., 2012, 6(3), 1877–1879], is perhaps nowhere more evident than in scanning transmission electron microscopy (STEM). Advances in STEM have endowed this technique with several powerful and complimentary capabilities. For example, the application of high-angle annular dark-field imaging has made possible real-space imaging at subangstrom resolution with Z-contrast (Z = atomic number). Further advances have wrought: simultaneous real-space imaging and elemental identification by using electron energy loss spectroscopy (EELS); 3-dimensional (3D) mapping by depth sectioning; monitoring of surface diffusion by time-sequencing of images; reduced electron energy imaging formore » probing graphenes; etc. In this paper we review how these advances, often coupled with first-principles theory, have led to interesting and important new insights into the physical chemistry of materials. We then review in detail a few specific applications that highlight some of these STEM capabilities.« less

  10. Insights into the physical chemistry of materials from advances in HAADF-STEM

    SciTech Connect

    Sohlberg, Karl; Pennycook, Timothy J.; Zhou, Wu; Pennycook, Stephen J.

    2014-11-13

    The observation that, ‘‘New tools lead to new science’’[P. S. Weiss, ACS Nano., 2012, 6(3), 1877–1879], is perhaps nowhere more evident than in scanning transmission electron microscopy (STEM). Advances in STEM have endowed this technique with several powerful and complimentary capabilities. For example, the application of high-angle annular dark-field imaging has made possible real-space imaging at subangstrom resolution with Z-contrast (Z = atomic number). Further advances have wrought: simultaneous real-space imaging and elemental identification by using electron energy loss spectroscopy (EELS); 3-dimensional (3D) mapping by depth sectioning; monitoring of surface diffusion by time-sequencing of images; reduced electron energy imaging for probing graphenes; etc. In this paper we review how these advances, often coupled with first-principles theory, have led to interesting and important new insights into the physical chemistry of materials. We then review in detail a few specific applications that highlight some of these STEM capabilities.

  11. XII Advanced Computing and Analysis Techniques in Physics Research

    NASA Astrophysics Data System (ADS)

    Speer, Thomas; Carminati, Federico; Werlen, Monique

    November 2008 will be a few months after the official start of LHC when the highest quantum energy ever produced by mankind will be observed by the most complex piece of scientific equipment ever built. LHC will open a new era in physics research and push further the frontier of Knowledge This achievement has been made possible by new technological developments in many fields, but computing is certainly the technology that has made possible this whole enterprise. Accelerator and detector design, construction management, data acquisition, detectors monitoring, data analysis, event simulation and theoretical interpretation are all computing based HEP activities but also occurring many other research fields. Computing is everywhere and forms the common link between all involved scientists and engineers. The ACAT workshop series, created back in 1990 as AIHENP (Artificial Intelligence in High Energy and Nuclear Research) has been covering the tremendous evolution of computing in its most advanced topics, trying to setup bridges between computer science, experimental and theoretical physics. Conference web-site: http://acat2008.cern.ch/ Programme and presentations: http://indico.cern.ch/conferenceDisplay.py?confId=34666

  12. A new computerised advanced theory of mind measure for children with Asperger syndrome: the ATOMIC.

    PubMed

    Beaumont, Renae B; Sofronoff, Kate

    2008-02-01

    This study examined the ability of children with Asperger Syndrome (AS) to attribute mental states to characters in a new computerised, advanced theory of mind measure: The Animated Theory of Mind Inventory for Children (ATOMIC). Results showed that children with AS matched on IQ, verbal comprehension, age and gender performed equivalently on central coherence questions, but more poorly on the theory of mind questions compared with controls. A significant relationship was found between performance on ATOMIC and accuracy of mental state explanations provided on (Happé's, Journal of Autism and Developmental Disorders, 24, 129-154, 1994) Strange Stories Task, supporting the validity of the new measure. Limitations of the study and suggestions for future research are discussed.

  13. Physics and Its Multiple Roles in the International Atomic Energy Agency

    NASA Astrophysics Data System (ADS)

    Massey, Charles D.

    2017-01-01

    The IAEA is the world's centre for cooperation in the nuclear field. It was set up as the world's ``Atoms for Peace'' organization in 1957 within the United Nations family. The Agency works with its Member States and multiple partners worldwide to promote the safe, secure and peaceful use of nuclear technologies. Three main areas of work underpin the IAEA's mission: Safety and Security, Science and Technology, and Safeguards and Verification. To carry out its mission, the Agency is authorized to encourage and assist research on, and development and practical application of, atomic energy for peaceful uses throughout the world; foster the exchange of scientific and technical information on peaceful uses of atomic energy; and encourage the exchange of training of scientists and experts in the field of peaceful uses of atomic energy. Nowadays, nuclear physics and nuclear technology are applied in a great variety of social areas, such as power production, medical diagnosis and therapies, environmental protection, security control, material tests, food processing, waste treatments, agriculture and artifacts analysis. This presentation will cover the role and practical application of physics at the IAEA, and, in particular, focus on the role physics has, and will play, in nuclear security.

  14. Interfaces in Heterogeneous Catalysts: Advancing Mechanistic Understanding through Atomic-Scale Measurements.

    PubMed

    Gao, Wenpei; Hood, Zachary D; Chi, Miaofang

    2017-02-16

    interfaces and providing deeper insight for fine-tuning and optimizing catalyst properties. Scanning transmission electron microscopy (STEM) has long been a primary characterization technique used for studying nanomaterials because of its exceptional imaging resolution and simultaneous chemical analysis. Over the past decade, advances in STEM, that is, the commercialization of both aberration correctors and monochromators, have significantly improved the spatial and energy resolution. Imaging atomic structures with subangstrom resolution and identifying chemical species with single-atom sensitivity are now routine for STEM. These advancements have greatly benefitted catalytic research. For example, the roles of lattice strain and surface elemental distribution and their effect on catalytic stability and reactivity have been well documented in bimetallic catalysts. In addition, three-dimensional atomic structures revealed by STEM tomography have been integrated in theoretical modeling for predictive catalyst NP design. Recent developments in stable electronic and mechanical devices have opened opportunities to monitor the evolution of catalysts in operando under synthesis and reaction conditions; high-speed direct electron detectors have achieved sub-millisecond time resolutions and allow for rapid structural and chemical changes to be captured. Investigations of catalysts using these latest microscopy techniques have provided new insights into atomic-level catalytic mechanisms. Further integration of new microscopy methods is expected to provide multidimensional descriptions of interfaces under relevant synthesis and reaction conditions. In this Account, we discuss recent insights on understanding catalyst activity, selectivity, and stability using advanced STEM techniques, with an emphasis on how critical interfaces dictate the performance of precious metal-based heterogeneous catalysts. The role of extended interfacial structures, including those between core and shell

  15. Advanced quantitative measurement methodology in physics education research

    NASA Astrophysics Data System (ADS)

    Wang, Jing

    The ultimate goal of physics education research (PER) is to develop a theoretical framework to understand and improve the learning process. In this journey of discovery, assessment serves as our headlamp and alpenstock. It sometimes detects signals in student mental structures, and sometimes presents the difference between expert understanding and novice understanding. Quantitative assessment is an important area in PER. Developing research-based effective assessment instruments and making meaningful inferences based on these instruments have always been important goals of the PER community. Quantitative studies are often conducted to provide bases for test development and result interpretation. Statistics are frequently used in quantitative studies. The selection of statistical methods and interpretation of the results obtained by these methods shall be connected to the education background. In this connecting process, the issues of educational models are often raised. Many widely used statistical methods do not make assumptions on the mental structure of subjects, nor do they provide explanations tailored to the educational audience. There are also other methods that consider the mental structure and are tailored to provide strong connections between statistics and education. These methods often involve model assumption and parameter estimation, and are complicated mathematically. The dissertation provides a practical view of some advanced quantitative assessment methods. The common feature of these methods is that they all make educational/psychological model assumptions beyond the minimum mathematical model. The purpose of the study is to provide a comparison between these advanced methods and the pure mathematical methods. The comparison is based on the performance of the two types of methods under physics education settings. In particular, the comparison uses both physics content assessments and scientific ability assessments. The dissertation includes three

  16. PET/CT: underlying physics, instrumentation, and advances.

    PubMed

    Torres Espallardo, I

    2017-01-12

    Since it was first introduced, the main goal of PET/CT has been to provide both PET and CT images with high clinical quality and to present them to radiologists and specialists in nuclear medicine as a fused, perfectly aligned image. The use of fused PET and CT images quickly became routine in clinical practice, showing the great potential of these hybrid scanners. Thanks to this success, manufacturers have gone beyond considering CT as a mere attenuation corrector for PET, concentrating instead on design high performance PET and CT scanners with more interesting features. Since the first commercial PET/CT scanner became available in 2001, both the PET component and the CT component have improved immensely. In the case of PET, faster scintillation crystals with high stopping power such as LYSO crystals have enabled more sensitive devices to be built, making it possible to reduce the number of undesired coincidence events and to use time of flight (TOF) techniques. All these advances have improved lesion detection, especially in situations with very noisy backgrounds. Iterative reconstruction methods, together with the corrections carried out during the reconstruction and the use of the point-spread function, have improved image quality. In parallel, CT instrumentation has also improved significantly, and 64- and 128-row detectors have been incorporated into the most modern PET/CT scanners. This makes it possible to obtain high quality diagnostic anatomic images in a few seconds that both enable the correction of PET attenuation and provide information for diagnosis. Furthermore, nowadays nearly all PET/CT scanners have a system that modulates the dose of radiation that the patient is exposed to in the CT study in function of the region scanned. This article reviews the underlying physics of PET and CT imaging separately, describes the changes in the instrumentation and standard protocols in a combined PET/CT system, and finally points out the most important

  17. Advancing reservoir operation description in physically based hydrological models

    NASA Astrophysics Data System (ADS)

    Anghileri, Daniela; Giudici, Federico; Castelletti, Andrea; Burlando, Paolo

    2016-04-01

    Last decades have seen significant advances in our capacity of characterizing and reproducing hydrological processes within physically based models. Yet, when the human component is considered (e.g. reservoirs, water distribution systems), the associated decisions are generally modeled with very simplistic rules, which might underperform in reproducing the actual operators' behaviour on a daily or sub-daily basis. For example, reservoir operations are usually described by a target-level rule curve, which represents the level that the reservoir should track during normal operating conditions. The associated release decision is determined by the current state of the reservoir relative to the rule curve. This modeling approach can reasonably reproduce the seasonal water volume shift due to reservoir operation. Still, it cannot capture more complex decision making processes in response, e.g., to the fluctuations of energy prices and demands, the temporal unavailability of power plants or varying amount of snow accumulated in the basin. In this work, we link a physically explicit hydrological model with detailed hydropower behavioural models describing the decision making process by the dam operator. In particular, we consider two categories of behavioural models: explicit or rule-based behavioural models, where reservoir operating rules are empirically inferred from observational data, and implicit or optimization based behavioural models, where, following a normative economic approach, the decision maker is represented as a rational agent maximising a utility function. We compare these two alternate modelling approaches on the real-world water system of Lake Como catchment in the Italian Alps. The water system is characterized by the presence of 18 artificial hydropower reservoirs generating almost 13% of the Italian hydropower production. Results show to which extent the hydrological regime in the catchment is affected by different behavioural models and reservoir

  18. Recent Development of Advanced Electrode Materials by Atomic Layer Deposition for Electrochemical Energy Storage

    PubMed Central

    2016-01-01

    Electrode materials play a decisive role in almost all electrochemical energy storage devices, determining their overall performance. Proper selection, design and fabrication of electrode materials have thus been regarded as one of the most critical steps in achieving high electrochemical energy storage performance. As an advanced nanotechnology for thin films and surfaces with conformal interfacial features and well controllable deposition thickness, atomic layer deposition (ALD) has been successfully developed for deposition and surface modification of electrode materials, where there are considerable issues of interfacial and surface chemistry at atomic and nanometer scale. In addition, ALD has shown great potential in construction of novel nanostructured active materials that otherwise can be hardly obtained by other processing techniques, such as those solution‐based processing and chemical vapor deposition (CVD) techniques. This review focuses on the recent development of ALD for the design and delivery of advanced electrode materials in electrochemical energy storage devices, where typical examples will be highlighted and analyzed, and the merits and challenges of ALD for applications in energy storage will also be discussed. PMID:27840793

  19. Recent Development of Advanced Electrode Materials by Atomic Layer Deposition for Electrochemical Energy Storage.

    PubMed

    Guan, Cao; Wang, John

    2016-10-01

    Electrode materials play a decisive role in almost all electrochemical energy storage devices, determining their overall performance. Proper selection, design and fabrication of electrode materials have thus been regarded as one of the most critical steps in achieving high electrochemical energy storage performance. As an advanced nanotechnology for thin films and surfaces with conformal interfacial features and well controllable deposition thickness, atomic layer deposition (ALD) has been successfully developed for deposition and surface modification of electrode materials, where there are considerable issues of interfacial and surface chemistry at atomic and nanometer scale. In addition, ALD has shown great potential in construction of novel nanostructured active materials that otherwise can be hardly obtained by other processing techniques, such as those solution-based processing and chemical vapor deposition (CVD) techniques. This review focuses on the recent development of ALD for the design and delivery of advanced electrode materials in electrochemical energy storage devices, where typical examples will be highlighted and analyzed, and the merits and challenges of ALD for applications in energy storage will also be discussed.

  20. Recent Advances in Atomic Metal Doping of Carbon-based Nanomaterials for Energy Conversion.

    PubMed

    Bayatsarmadi, Bita; Zheng, Yao; Vasileff, Anthony; Qiao, Shi-Zhang

    2017-04-12

    Nanostructured metal-contained catalysts are one of the most widely used types of catalysts applied to facilitate some of sluggish electrochemical reactions. However, the high activity of these catalysts cannot be sustained over a variety of pH ranges. In an effort to develop highly active and stable metal-contained catalysts, various approaches have been pursued with an emphasis on metal particle size reduction and doping on carbon-based supports. These techniques enhances the metal-support interactions, originating from the chemical bonding effect between the metal dopants and carbon support and the associated interface, as well as the charge transfer between the atomic metal species and carbon framework. This provides an opportunity to tune the well-defined metal active centers and optimize their activity, selectivity and stability of this type of (electro)catalyst. Herein, recent advances in synthesis strategies, characterization and catalytic performance of single atom metal dopants on carbon-based nanomaterials are highlighted with attempts to understand the electronic structure and spatial arrangement of individual atoms as well as their interaction with the supports. Applications of these new materials in a wide range of potential electrocatalytic processes in renewable energy conversion systems are also discussed with emphasis on future directions in this active field of research.

  1. Unveiling the structural arrangements responsible for the atomic dynamics in metallic glasses during physical aging

    PubMed Central

    Giordano, V. M.; Ruta, B

    2016-01-01

    Understanding and controlling physical aging, that is, the spontaneous temporal evolution of out-of-equilibrium systems, represents one of the greatest tasks in material science. Recent studies have revealed the existence of a complex atomic motion in metallic glasses, with different aging regimes in contrast with the typical continuous aging observed in macroscopic quantities. By combining dynamical and structural synchrotron techniques, here for the first time we directly connect previously identified microscopic structural mechanisms with the peculiar atomic motion, providing a broader unique view of their complexity. We show that the atomic scale is dominated by the interplay between two processes: rearrangements releasing residual stresses related to a cascade mechanism of relaxation, and medium range ordering processes, which do not affect the local density, likely due to localized relaxations of liquid-like regions. As temperature increases, a surprising additional secondary relaxation process sets in, together with a faster medium range ordering, likely precursors of crystallization. PMID:26787443

  2. Atomic Physics Effects on Convergent, Child-Langmuir Ion Flow between Nearly Transparent Electrodes

    SciTech Connect

    Santarius, John F.; Emmert, Gilbert A.

    2013-11-07

    Research during this project at the University of Wisconsin Fusion Technology Institute (UW FTI) on ion and neutral flow through an arbitrary, monotonic potential difference created by nearly transparent electrodes accomplished the following: (1) developed and implemented an integral equation approach for atomic physics effects in helium plasmas; (2) extended the analysis to coupled integral equations that treat atomic and molecular deuterium ions and neutrals; (3) implemented the key deuterium and helium atomic and molecular cross sections; (4) added negative ion production and related cross sections; and (5) benchmarked the code against experimental results. The analysis and codes treat the species D0, D20, D+, D2+, D3+, D and, separately at present, He0 and He+. Extensions enhanced the analysis and related computer codes to include He++ ions plus planar and cylindrical geometries.

  3. Physics basis for an advanced physics and advanced technology tokamak power plant configuration: ARIES-ACT1

    DOE PAGES

    Kessel, C. E.; Poli, F. M.; Ghantous, K.; ...

    2015-01-01

    Here, the advanced physics and advanced technology tokamak power plant ARIES-ACT1 has a major radius of 6.25 m at an aspect ratio of 4.0, toroidal field of 6.0 T, strong shaping with elongation of 2.2, and triangularity of 0.63. The broadest pressure cases reached wall-stabilized βN ~ 5.75, limited by n = 3 external kink mode requiring a conducting shell at b/a = 0.3, requiring plasma rotation, feedback, and/or kinetic stabilization. The medium pressure peaking case reaches βN = 5.28 with BT = 6.75, while the peaked pressure case reaches βN < 5.15. Fast particle magnetohydrodynamic stability shows that themore » alpha particles are unstable, but this leads to redistribution to larger minor radius rather than loss from the plasma. Edge and divertor plasma modeling shows that 75% of the power to the divertor can be radiated with an ITER-like divertor geometry, while >95% can be radiated in a stable detached mode with an orthogonal target and wide slot geometry. The bootstrap current fraction is 91% with a q95 of 4.5, requiring ~1.1 MA of external current drive. This current is supplied with 5 MW of ion cyclotron radio frequency/fast wave and 40 MW of lower hybrid current drive. Electron cyclotron is most effective for safety factor control over ρ~0.2 to 0.6 with 20 MW. The pedestal density is ~0.9×1020/m3, and the temperature is ~4.4 keV. The H98 factor is 1.65, n/nGr = 1.0, and the ratio of net power to threshold power is 2.8 to 3.0 in the flattop.« less

  4. The Physics Basis For An Advanced Physics And Advanced Technology Tokamak Power Plant Configuration, ARIES-ACT1

    SciTech Connect

    Charles Kessel, et al

    2014-03-05

    The advanced physics and advanced technology tokamak power plant ARIES-ACT1 has a major radius of 6.25 m at aspect ratio of 4.0, toroidal field of 6.0 T, strong shaping with elongation of 2.2 and triangularity of 0.63. The broadest pressure cases reached wall stabilized βN ~ 5.75, limited by n=3 external kink mode requiring a conducting shell at b/a = 0.3, and requiring plasma rotation, feedback, and or kinetic stabilization. The medium pressure peaking case reached βN = 5.28 with BT = 6.75, while the peaked pressure case reaches βN < 5.15. Fast particle MHD stability shows that the alpha particles are unstable, but this leads to redistribution to larger minor radius rather than loss from the plasma. Edge and divertor plasma modeling show that about 75% of the power to the divertor can be radiated with an ITER-like divertor geometry, while over 95% can be radiated in a stable detached mode with an orthogonal target and wide slot geometry. The bootstrap current fraction is 91% with a q95 of 4.5, requiring about ~ 1.1 MA of external current drive. This current is supplied with 5 MW of ICRF/FW and 40 MW of LHCD. EC was examined and is most effective for safety factor control over ρ ~ 0.2-0.6 with 20 MW. The pedestal density is ~ 0.9x1020 /m3 and the temperature is ~ 4.4 keV. The H98 factor is 1.65, n/nGr = 1.0, and the net power to LH threshold power is 2.8- 3.0 in the flattop.

  5. Physics basis for an advanced physics and advanced technology tokamak power plant configuration: ARIES-ACT1

    SciTech Connect

    Kessel, C. E.; Poli, F. M.; Ghantous, K.; Gorelenkov, N. N.; Rensink, M. E.; Rognlien, T. D.; Snyder, P. B.; St. John, H.; Turnbull, A. D.

    2015-01-01

    Here, the advanced physics and advanced technology tokamak power plant ARIES-ACT1 has a major radius of 6.25 m at an aspect ratio of 4.0, toroidal field of 6.0 T, strong shaping with elongation of 2.2, and triangularity of 0.63. The broadest pressure cases reached wall-stabilized βN ~ 5.75, limited by n = 3 external kink mode requiring a conducting shell at b/a = 0.3, requiring plasma rotation, feedback, and/or kinetic stabilization. The medium pressure peaking case reaches βN = 5.28 with BT = 6.75, while the peaked pressure case reaches βN < 5.15. Fast particle magnetohydrodynamic stability shows that the alpha particles are unstable, but this leads to redistribution to larger minor radius rather than loss from the plasma. Edge and divertor plasma modeling shows that 75% of the power to the divertor can be radiated with an ITER-like divertor geometry, while >95% can be radiated in a stable detached mode with an orthogonal target and wide slot geometry. The bootstrap current fraction is 91% with a q95 of 4.5, requiring ~1.1 MA of external current drive. This current is supplied with 5 MW of ion cyclotron radio frequency/fast wave and 40 MW of lower hybrid current drive. Electron cyclotron is most effective for safety factor control over ρ~0.2 to 0.6 with 20 MW. The pedestal density is ~0.9×1020/m3, and the temperature is ~4.4 keV. The H98 factor is 1.65, n/nGr = 1.0, and the ratio of net power to threshold power is 2.8 to 3.0 in the flattop.

  6. Atomic physics with highly charged ions: Progress report, 15 August 1985--14 August 1988

    SciTech Connect

    Richard, P.

    1988-08-01

    The study of inelastic collision phenomena with highly charged projectile ions and the interpretation of spectral features resulting from these collisions remain as the major focal points in the atomic physics research at the J.R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas. The title of the research project ''Atomic Physics with Highly Charged Ions'' speaks to these points. The experimental work is made possible locally by the use of relatively high velocity, highly charged projectiles (v typically 5% c) as obtained from the 6 MV tandem Van de Graaff accelerator. The work in the past few years has divided into collisions at high velocity using the primary beams from the accelerator and collisions at low velocity using secondary beams (recoil ions produced in a high velocity collision) in a so-called SIRS (Secondary Ion Recoil Source) geometry. Theoretical calculations have been performed to accurately describe inelastic scattering processes of the one-electron and many-electron type, and to accurately predict atomic transition energies and intensities for x-rays and Auger electrons. Correlation effects and polarization phenomena in ion-atom collisions have been investigated.

  7. Informal proposal for an Atomic Physics Facility at the National Synchrotron Light Source

    SciTech Connect

    Jones, K.W.; Johnson, B.M.; Meron, M.

    1986-01-01

    An Atomic Physics Facility (APF) for experiments that will use radiation from a superconducting wiggler on the NSLS X-13 port is described. The scientific justification for the APF is given and the elements of the facility are discussed. It is shown that it will be possible to conduct a uniquely varied set of experiments that can probe most aspects of atomic physics. A major component of the proposal is a heavy-ion storage ring capable of containing ions with energies of about 10 MeV/nucleon. The ring can be filled with heavy ions produced at the BNL MP Tandem Laboratory or from independent ion-source systems. A preliminary cost estimate for the facility is presented.

  8. Construction and characterization of external cavity diode lasers for atomic physics.

    PubMed

    Hardman, Kyle S; Bennetts, Shayne; Debs, John E; Kuhn, Carlos C N; McDonald, Gordon D; Robins, Nick

    2014-04-24

    Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and Titanium Sapphire lasers as the workhorse laser of atomic physics labs. Their versatility and prolific use throughout atomic physics in applications such as absorption spectroscopy and laser cooling makes it imperative for incoming students to gain a firm practical understanding of these lasers. This publication builds upon the seminal work by Wieman, updating components, and providing a video tutorial. The setup, frequency locking and performance characterization of an ECDL will be described. Discussion of component selection and proper mounting of both diodes and gratings, the factors affecting mode selection within the cavity, proper alignment for optimal external feedback, optics setup for coarse and fine frequency sensitive measurements, a brief overview of laser locking techniques, and laser linewidth measurements are included.

  9. Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

    PubMed Central

    Hardman, Kyle S.; Bennetts, Shayne; Debs, John E.; Kuhn, Carlos C. N.; McDonald, Gordon D.; Robins, Nick

    2014-01-01

    Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and Titanium Sapphire lasers as the workhorse laser of atomic physics labs1,2. Their versatility and prolific use throughout atomic physics in applications such as absorption spectroscopy and laser cooling1,2 makes it imperative for incoming students to gain a firm practical understanding of these lasers. This publication builds upon the seminal work by Wieman3, updating components, and providing a video tutorial. The setup, frequency locking and performance characterization of an ECDL will be described. Discussion of component selection and proper mounting of both diodes and gratings, the factors affecting mode selection within the cavity, proper alignment for optimal external feedback, optics setup for coarse and fine frequency sensitive measurements, a brief overview of laser locking techniques, and laser linewidth measurements are included. PMID:24796259

  10. From the Dawn of Nuclear Physics to the First Atomic Bombs

    NASA Astrophysics Data System (ADS)

    Woolbright, Stephen; Schumacher, Jacob; Michonova-Alexova, Ekaterina

    2014-03-01

    This work gives a fresh look at the major discoveries leading to nuclear fission within the historical perspective. The focus is on the main contributors to the discoveries in nuclear physics, leading to the idea of fission and its application to the creation of the atomic bombs used at the end of the World War II. The present work is a more complete review on the history of the nuclear physics discoveries and their application to the atomic bomb. In addition to the traditional approach to the topic, focusing mainly on the fundamental physics discoveries in Europe and on the Manhattan Project in the United States, the nuclear research in Japan is also emphasized. Along with that, a review of the existing credible scholar publications, providing evidence for possible atomic bomb research in Japan, is provided. Proper credit is given to the women physicists, whose contributions had not always been recognized. Considering the historical and political situation at the time of the scientific discoveries, thought-provoking questions about decision-making, morality, and responsibility are also addressed. The work refers to the contributions of over 20 Nobel Prize winners. EM-A is grateful to Prof. Walter Grunden and to Prof. Emeritus Shadahiko Kano, Prof. Emeritus Monitori Hoshi for sharing their own notes, documents, and references, and to CCCU for sponsoring her participation in the 2013 Nuclear Weapons Seminar in Japan.

  11. TIMSS Advanced 2015 and Advanced Placement Calculus & Physics. A Framework Analysis. Research in Review 2016-1

    ERIC Educational Resources Information Center

    Lazzaro, Christopher; Jones, Lee; Webb, David C.; Grover, Ryan; Di Giacomo, F. Tony; Marino, Katherine Adele

    2016-01-01

    This report will determine to what degree the AP Physics 1 and 2 and AP Calculus AB and BC frameworks are aligned with the Trends in International Mathematics and Science Study (TIMSS) Advanced Physics and Mathematics frameworks. This will enable an exploration of any differences in content coverage and levels of complexity, and will set the stage…

  12. Medical physics in Europe following recommendations of the International Atomic Energy Agency

    PubMed Central

    Lopes, Maria do Carmo; Drljević, Advan; Gershkevitsh, Eduard; Pesznyak, Csilla

    2016-01-01

    Background Medical physics is a health profession where principles of applied physics are mostly directed towards the application of ionizing radiation in medicine. The key role of the medical physics expert in safe and effective use of ionizing radiation in medicine was widely recognized in recent European reference documents like the European Union Council Directive 2013/59/EURATOM (2014), and European Commission Radiation Protection No. 174, European Guidelines on Medical Physics Expert (2014). Also the International Atomic Energy Agency (IAEA) has been outspoken in supporting and fostering the status of medical physics in radiation medicine through multiple initiatives as technical and cooperation projects and important documents like IAEA Human Health Series No. 25, Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists (2013) and the International Basic Safety Standards, General Safety Requirements Part 3 (2014). The significance of these documents and the recognition of the present insufficient fulfilment of the requirements and recommendations in many European countries have led the IAEA to organize in 2015 the Regional Meeting on Medical Physics in Europe, where major issues in medical physics in Europe were discussed. Most important outcomes of the meeting were the recommendations addressed to European member states and the survey on medical physics status in Europe conducted by the IAEA and European Federation of Organizations for Medical Physics. Conclusions Published recommendations of IAEA Regional Meeting on Medical Physics in Europe shall be followed and enforced in all European states. Appropriate qualification framework including education, clinical specialization, certification and registration of medical physicists shall be established and international recommendation regarding staffing levels in the field of medical physics shall be fulfilled in particular. European states have clear

  13. Advances in quantitative nanoscale subsurface imaging by mode-synthesizing atomic force microscopy

    SciTech Connect

    Vitry, P.; Bourillot, E.; Plassard, C.; Lacroute, Y.; Lesniewska, E.; Tetard, L.

    2014-08-04

    This paper reports on advances toward quantitative non-destructive nanoscale subsurface investigation of a nanofabricated sample based on mode synthesizing atomic force microscopy with heterodyne detection, addressing the need to correlate the role of actuation frequencies of the probe f{sub p} and the sample f{sub s} with depth resolution for 3D tomography reconstruction. Here, by developing a simple model and validating the approach experimentally through the study of the nanofabricated calibration depth samples consisting of buried metallic patterns, we demonstrate avenues for quantitative nanoscale subsurface imaging. Our findings enable the reconstruction of the sample depth profile and allow high fidelity resolution of the buried nanostructures. Non-destructive quantitative nanoscale subsurface imaging offers great promise in the study of the structures and properties of complex systems at the nanoscale.

  14. Stalking the Anti-Racist Atom: Engaging Educational Equity and Diversity in Physics Teaching

    NASA Astrophysics Data System (ADS)

    Hodari, Apriel K.

    2006-12-01

    One of the first articles I ever read on diversity in physics education stated, “There’s no such thing as an anti-racist atom.” This perspective, that the science of physics is itself inherently unbiased, illustrates the difficulty of engaging our intellectual community on this topic. We genuinely believe that our science is devoid of the complications of the human condition, and therefore we need not worry about these things. It is clear however, as people competing for scarce resources in a non-equitable society, we engage in all of the same behaviors everyone else does, include those that work against equity and diversity. Over the last several years, my colleagues and I have held workshops aimed at addressing educational equity and diversity in physics teaching. In this discussion, I will present some of the questions we have posed, along with lessons learned and ideas about what we can do next.

  15. Optical and magnetic properties of a transparent garnet film for atomic physics experiments

    NASA Astrophysics Data System (ADS)

    Saito, Mari; Tajima, Ryoichi; Kiyosawa, Ryota; Nagata, Yugo; Shimada, Hiroyuki; Ishibashi, Takayuki; Hatakeyama, Atsushi

    2016-12-01

    We investigated the optical and magnetic properties of a transparent magnetic garnet with a particular focus on its applications to atomic physics experiments. The garnet film used in this study was a magnetically soft material that was originally designed for a Faraday rotator at optical communication wavelengths in the near infrared region. The film had a thickness of 2.1 μm and a small optical loss at a wavelength of λ =780 nm resonant with Rb atoms. The Faraday effect was also small and, thus, barely affected the polarization of light at λ =780 nm. In contrast, large Faraday rotation angles at shorter wavelengths enabled us to visualize magnetic domains, which were perpendicularly magnetized in alternate directions with a period of 3.6 μm. We confirmed the generation of an evanescent wave on the garnet film, which can be used for the optical observation and manipulation of atoms on the surface of the film. Finally, we demonstrated a magnetic mirror for laser-cooled Rb atoms using the garnet film.

  16. Resolving all-order method convergence problems for atomic physics applications

    SciTech Connect

    Gharibnejad, H.; Derevianko, A.; Eliav, E.; Safronova, M. S.

    2011-05-15

    The development of the relativistic all-order method where all single, double, and partial triple excitations of the Dirac-Hartree-Fock wave function are included to all orders of perturbation theory led to many important results for the study of fundamental symmetries, development of atomic clocks, ultracold atom physics, and others, as well as provided recommended values of many atomic properties critically evaluated for their accuracy for a large number of monovalent systems. This approach requires iterative solutions of the linearized coupled-cluster equations leading to convergence issues in some cases where correlation corrections are particularly large or lead to an oscillating pattern. Moreover, these issues also lead to similar problems in the configuration-interaction (CI)+all-order method for many-particle systems. In this work, we have resolved most of the known convergence problems by applying two different convergence stabilizer methods, namely, reduced linear equation and direct inversion of iterative subspace. Examples are presented for B, Al, Zn{sup +}, and Yb{sup +}. Solving these convergence problems greatly expands the number of atomic species that can be treated with the all-order methods and is anticipated to facilitate many interesting future applications.

  17. Dips in spectral line profiles and their applications in plasma physics and atomic physics

    NASA Astrophysics Data System (ADS)

    Dalimier, E.; Oks, E.; Renner, O.

    2017-03-01

    We review studies of two kinds of dips in spectral line profiles emitted by plasmas - the dips that have been predicted theoretically and observed experimentally: Langmuir-wave-caused dips (L-dips) and charge-exchange-caused dips (X-dips). There is a principal difference with respect to positions of L-dips and X-dips relative to the unperturbed wavelength of a spectral line: positions of L-dips scale with the electron density Ne roughly as Ne1/2, while positions of X-dips are almost independent of Ne (the dependence is much weaker than for L-dips). L-dips and X-dips phenomena are important both fundamentally and practically. The fundamental importance is due to a rich physics behind each of these phenomena. As for important practical applications, they are as follows. Observations of L-dips constitute a very accurate method to measure the electron density in plasmas - the method that does not require the knowledge of the electron temperature. L-dips also allow measuring the amplitude of the electric field of Langmuir waves - the only one spectroscopic method available for this purpose. Observations of X-dips provide an opportunity to determine rate coefficient of charge exchange between multi-charged ions. This is an important reference data virtually inaccessible by other experimental methods. The rate coefficients of charge exchange are important for magnetic fusion in Tokamaks, for population inversion in the soft x-ray and VUV ranges, for ion storage devices, as well as for astrophysics (e.g., for the solar plasma and for determining the physical state of planetary nebulae).

  18. BOOK REVIEW: New Understanding Physics for Advanced Level

    NASA Astrophysics Data System (ADS)

    Breithaupt, Jim

    2000-09-01

    Breithaupt's new book is big: at 727 pages, it will be a hefty addition to any student's bag. According to the preface, the book is designed to help students achieve the transition from GCSE to A-level and to succeed well at this level. It also aims to cover the requirements of the compulsory parts of all new syllabuses and to cover most of the optional material, too. The book is organized into seven themes along traditional lines: mechanics, materials, fields, waves, electricity, inside the atom, and physics in medicine. Each theme begins with a colourful title page that outlines what the theme is about, lists the applications that students will meet in their reading, identifies prior learning from GCSE and gives a checklist of what students should be able to do once they have finished their reading of the theme. This is all very useful. The text of the book is illustrated with many colourful photographs, pictures and cartoons, but despite this it looks very dense. There are a lot of words on every page in a small font that makes them seem very unfriendly, and although the book claims to be readable I rather doubt that the layout will encourage voluntary reading of the text. Each chapter ends with a useful summary and a selection of short questions that allow students to test their understanding. Each theme has a set of multiple choice and long questions. Some of the questions have an icon referring the student to the accompanying CD (more of this later). There is much up-to-date material in the book. For example, the section on cosmology gives a brief description of the inflationary scenario within the Big Bang model of the origin of the universe, although no mechanism for the inflation is given, which might prove unsatisfying to some students. I do have some reservations about the presentation of some topics within the book: the discussion of relativistic mass, for example, states that `Einstein showed that the mass ... is given by the formula ...' and quotes

  19. TRIμP-Trapped Radioactive Atoms-μicrolaboratories for Fundamental Physics

    NASA Astrophysics Data System (ADS)

    Jungmann, K.; Berg, G. P.; Dammalapati, U.; Dendooven, P.; Dermois, O.; Harakeh, M. N.; Hoekstra, R.; Morgenstern, R.; Rogachevskiy, A.; Sanchez-Vega, M.; Timmermans, R.; Traykov, E.; Willmann, L.; Wilscut, H. W.

    At the Kernfysisch Versneller Instituut (KVI) in Groningen, NL, a new facility (TRIμP) is under development. Radioactive nuclei will be produced using heavy ion beams from the superconducting AGOR cyclotron. They are then slowed down and finally trapped in ion or atomic traps in order to perform precision experiments with them. The facility will be open for use by the worldwide community. The present local research programme includes precision studies of nuclear β-decays through β-neutrino (recoil nucleus) momentum correlations in weak decays as well as searches for permanent electric dipole moments in heavy atomic systems. Such experiments offer a large potential for discovering new physics or to put sensitive limits on parameters in models beyond standard theory.

  20. An open source digital servo for atomic, molecular, and optical physics experiments

    PubMed Central

    Leibrandt, D. R.; Heidecker, J.

    2016-01-01

    We describe a general purpose digital servo optimized for feedback control of lasers in atomic, molecular, and optical physics experiments. The servo is capable of feedback bandwidths up to roughly 1 MHz (limited by the 320 ns total latency); loop filter shapes up to fifth order; multiple-input, multiple-output control; and automatic lock acquisition. The configuration of the servo is controlled via a graphical user interface, which also provides a rudimentary software oscilloscope and tools for measurement of system transfer functions. We illustrate the functionality of the digital servo by describing its use in two example scenarios: frequency control of the laser used to probe the narrow clock transition of 27Al+ in an optical atomic clock, and length control of a cavity used for resonant frequency doubling of a laser. PMID:26724014

  1. An open source digital servo for atomic, molecular, and optical physics experiments

    SciTech Connect

    Leibrandt, D. R. Heidecker, J.

    2015-12-15

    We describe a general purpose digital servo optimized for feedback control of lasers in atomic, molecular, and optical physics experiments. The servo is capable of feedback bandwidths up to roughly 1 MHz (limited by the 320 ns total latency); loop filter shapes up to fifth order; multiple-input, multiple-output control; and automatic lock acquisition. The configuration of the servo is controlled via a graphical user interface, which also provides a rudimentary software oscilloscope and tools for measurement of system transfer functions. We illustrate the functionality of the digital servo by describing its use in two example scenarios: frequency control of the laser used to probe the narrow clock transition of {sup 27}Al{sup +} in an optical atomic clock, and length control of a cavity used for resonant frequency doubling of a laser.

  2. Testing for a cosmological influence on local physics using atomic and gravitational clocks

    NASA Technical Reports Server (NTRS)

    Adams, P. J.; Hellings, R. W.; Canuto, V. M.; Goldman, I.

    1983-01-01

    The existence of a possible influence of the large-scale structure of the universe on local physics is discussed. A particular realization of such an influence is discussed in terms of the behavior in time of atomic and gravitational clocks. Two natural categories of metric theories embodying a cosmic infuence exist. The first category has geodesic equations of motion in atomic units, while the second category has geodesic equations of motion in gravitational units. Equations of motion for test bodies are derived for both categories of theories in the appropriate parametrized post-Newtonian limit and are applied to the Solar System. Ranging data to the Viking lander on Mars are of sufficient precision to reveal (1) if such a cosmological influence exists at the level of Hubble's constant, and (2) which category of theories is appropriate for a descripton of the phenomenon.

  3. Spectroscopy and atomic physics of highly ionized Cr, Fe, and Ni for tokamak plasmas

    NASA Technical Reports Server (NTRS)

    Feldman, U.; Doschek, G. A.; Cheng, C.-C.; Bhatia, A. K.

    1980-01-01

    The paper considers the spectroscopy and atomic physics for some highly ionized Cr, Fe, and Ni ions produced in tokamak plasmas. Forbidden and intersystem wavelengths for Cr and Ni ions are extrapolated and interpolated using the known wavelengths for Fe lines identified in solar-flare plasmas. Tables of transition probabilities for the B I, C I, N I, O I, and F I isoelectronic sequences are presented, and collision strengths and transition probabilities for Cr, Fe, and Ni ions of the Be I sequence are given. Similarities of tokamak and solar spectra are discussed, and it is shown how the atomic data presented may be used to determine ion abundances and electron densities in low-density plasmas.

  4. The role of atomic and molecular physics for dissipative divertor operation in helium and deuterium plasmas

    NASA Astrophysics Data System (ADS)

    Canik, J. M.

    2016-10-01

    Recent experiments in DIII-D helium plasmas are examined to resolve the role of atomic and molecular physics in major discrepancies between experiment and modeling of dissipative divertor operation. Helium operation removes the complicated molecular processes of deuterium plasmas that are a prime candidate for the inability of standard fluid models (SOLPS, UEDGE) to reproduce dissipative divertor operation, primarily the consistent under-prediction of radiated power. With helium fueling, a high-recycling divertor was established with divertor densities increasing to ne,div >= 3 ×1020m-3 and temperatures decreasing to Te,div <= 2 eV as measured by divertor Thomson scattering (DTS). The electron pressure, pe , div decreased gradually with increasing density to less than 30% of the low density value. However, the ion flux to the divertor target did not decrease until the highest densities and lowest temperatures, Te,div <= 2 eV. In contrast, with deuterium operation, increasing density leads to a rapid transition from Te,div >= 10 eV to Te,div <= 3 eV, though both pe , div and ion flux do not decrease until Te,div <= 2 eV. These differences indicate an important role for molecular and atomic physics in the dynamics of divertor dissipation. Initial SOLPS modeling has reproduced ne and Te profiles at the midplane and divertor target, as well as the spatial structure of radiation patterns measured in moderate density helium plasmas. However, the modeled divertor radiation is less than measured, similar to deuterium simulations, suggesting processes more universal than species-specific atomic or molecular physics may be the source of radiation deficit. Detailed assessments of ne, Te profiles in the divertor volume, uniquely determined at DIII-D using DTS, are made along with analysis of measured and modeled line radiation to shed more light on these intriguing findings. Supported by the US DOE under DE-AC05-00OR22725.

  5. Gaining insight into the physics of dynamic atomic force microscopy in complex environments using the VEDA simulator.

    PubMed

    Kiracofe, Daniel; Melcher, John; Raman, Arvind

    2012-01-01

    Dynamic atomic force microscopy (dAFM) continues to grow in popularity among scientists in many different fields, and research on new methods and operating modes continues to expand the resolution, capabilities, and types of samples that can be studied. But many promising increases in capability are accompanied by increases in complexity. Indeed, interpreting modern dAFM data can be challenging, especially on complicated material systems, or in liquid environments where the behavior is often contrary to what is known in air or vacuum environments. Mathematical simulations have proven to be an effective tool in providing physical insight into these non-intuitive systems. In this article we describe recent developments in the VEDA (virtual environment for dynamic AFM) simulator, which is a suite of freely available, open-source simulation tools that are delivered through the cloud computing cyber-infrastructure of nanoHUB (www.nanohub.org). Here we describe three major developments. First, simulations in liquid environments are improved by enhancements in the modeling of cantilever dynamics, excitation methods, and solvation shell forces. Second, VEDA is now able to simulate many new advanced modes of operation (bimodal, phase-modulation, frequency-modulation, etc.). Finally, nineteen different tip-sample models are available to simulate the surface physics of a wide variety different material systems including capillary, specific adhesion, van der Waals, electrostatic, viscoelasticity, and hydration forces. These features are demonstrated through example simulations and validated against experimental data, in order to provide insight into practical problems in dynamic AFM.

  6. Gaining insight into the physics of dynamic atomic force microscopy in complex environments using the VEDA simulator

    NASA Astrophysics Data System (ADS)

    Kiracofe, Daniel; Melcher, John; Raman, Arvind

    2012-01-01

    Dynamic atomic force microscopy (dAFM) continues to grow in popularity among scientists in many different fields, and research on new methods and operating modes continues to expand the resolution, capabilities, and types of samples that can be studied. But many promising increases in capability are accompanied by increases in complexity. Indeed, interpreting modern dAFM data can be challenging, especially on complicated material systems, or in liquid environments where the behavior is often contrary to what is known in air or vacuum environments. Mathematical simulations have proven to be an effective tool in providing physical insight into these non-intuitive systems. In this article we describe recent developments in the VEDA (virtual environment for dynamic AFM) simulator, which is a suite of freely available, open-source simulation tools that are delivered through the cloud computing cyber-infrastructure of nanoHUB (www.nanohub.org). Here we describe three major developments. First, simulations in liquid environments are improved by enhancements in the modeling of cantilever dynamics, excitation methods, and solvation shell forces. Second, VEDA is now able to simulate many new advanced modes of operation (bimodal, phase-modulation, frequency-modulation, etc.). Finally, nineteen different tip-sample models are available to simulate the surface physics of a wide variety different material systems including capillary, specific adhesion, van der Waals, electrostatic, viscoelasticity, and hydration forces. These features are demonstrated through example simulations and validated against experimental data, in order to provide insight into practical problems in dynamic AFM.

  7. Ab Initio Study on Atomic Structures and Physical Properties of CdSe Quantum Nanodots

    DTIC Science & Technology

    2009-11-25

    CdSe quantum dots , with magic number (( CdSe )13, ( CdSe )19, ( CdSe )33 and ( CdSe )34 ). Effects of organic ligand binding on the stability of CdSe as well...calculations of optical absorption spectra for CdSe quantum dots , with magic number (( CdSe )13, ( CdSe )19, ( CdSe )33 and ( CdSe )34 ), have been calculated in...1 AOARD-08-4037 Title of Proposed Project: Ab initio study on atomic structures and physical

  8. Chapter Three - Atomic, Molecular, and Optical Physics in the Early Universe: From Recombination to Reionization

    NASA Astrophysics Data System (ADS)

    Glover, Simon C. O.; Chluba, Jens; Furlanetto, Steve R.; Pritchard, Jonathan R.; Savin, Daniel Wolf

    2014-08-01

    Our knowledge of the evolution of the early Universe hinges, in part, on our understanding of the underlying atomic, molecular, and optical (AMO) processes occurring during that epoch. Here we review the relevant AMO physics from when it first became important at a redshift of z ~ 6000, some 18,000 years after the Big Bang when electrons and ions began to recombine. The review continues through the formation of the first stars and galaxies and concludes after the radiation from these first objects has reionized the Universe at a z ~ 10, about a billion years after the Big Bang.

  9. Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants

    PubMed Central

    Hayano, Ryugo S.

    2010-01-01

    Antiprotonic helium atom, a metastable neutral system consisting of an antiproton, an electron and a helium nucleus, was serendipitously discovered, and has been studied at CERN’s antiproton decelerator facility. Its transition frequencies have recently been measured to nine digits of precision by laser spectroscopy. By comparing these experimental results with three-body QED calculations, the antiproton-to-electron massratio was determined as 1836.152674(5). This result contributed to the CODATA recommended values of the fundamental physical constants. PMID:20075605

  10. Application of the Finite Element Method in Atomic and Molecular Physics

    NASA Technical Reports Server (NTRS)

    Shertzer, Janine

    2007-01-01

    The finite element method (FEM) is a numerical algorithm for solving second order differential equations. It has been successfully used to solve many problems in atomic and molecular physics, including bound state and scattering calculations. To illustrate the diversity of the method, we present here details of two applications. First, we calculate the non-adiabatic dipole polarizability of Hi by directly solving the first and second order equations of perturbation theory with FEM. In the second application, we calculate the scattering amplitude for e-H scattering (without partial wave analysis) by reducing the Schrodinger equation to set of integro-differential equations, which are then solved with FEM.

  11. Nuclear-spin-independent short-range three-body physics in ultracold atoms.

    PubMed

    Gross, Noam; Shotan, Zav; Kokkelmans, Servaas; Khaykovich, Lev

    2010-09-03

    We investigate three-body recombination loss across a Feshbach resonance in a gas of ultracold 7Li atoms prepared in the absolute ground state and perform a comparison with previously reported results of a different nuclear-spin state [N. Gross, Phys. Rev. Lett. 103, 163202 (2009)]. We extend the previously reported universality in three-body recombination loss across a Feshbach resonance to the absolute ground state. We show that the positions and widths of recombination minima and Efimov resonances are identical for both states which indicates that the short-range physics is nuclear-spin independent.

  12. The Atomic Era: A new interdisciplinary course combining physics, the humanities and the social sciences

    NASA Astrophysics Data System (ADS)

    Carstens-Wickham, Belinda

    2001-05-01

    Southern Illinois University Edwardsville won funding from the federal interagency competition, Leadership Opportunity in Science and Humanities Education, which supported interdisciplinary courses combining the natural sciences and the humanities. The author analyses her experiences developing a very successful and popular interdisciplinary course, entitled The Atomic Era, which features a unique combination of physics, sociology and German studies taught jointly by a Physicist, a Sociologist and a Germanist. The objectives of the course, the laboratories and demonstrations, instructional goals, assignments, organization, testing, student and faculty assessment, expenses and the special challenges of coordinating three faculty members and a wide variety of topics and perspectives are addressed and analysed.

  13. ELASR - An electrostatic storage ring for atomic and molecular physics at KACST

    NASA Astrophysics Data System (ADS)

    El Ghazaly, Mohamed O. A.

    A new ELectrostAtic Storage Ring (ELASR) has been designed and built at the King Abdulaziz City for Science and Technology (KACST), in Riyadh, Saudi Arabia. It was developed to be the core of a new storage ring laboratory for atomic and molecular physics at KACST. ELASR follows the standard design of the pioneering storage ring ELISA and it thereby features a racetrack single-bend shaped ring. Complementary simulation code packages were used to work out the design under the requirements of the projected experiments. This paper reports a short description of the ELASR storage ring through an overview of its design and construction.

  14. Sixteenth International Conference on the physics of electronic and atomic collisions

    SciTech Connect

    Dalgarno, A.; Freund, R.S.; Lubell, M.S.; Lucatorto, T.B.

    1989-01-01

    This report contains abstracts of papers on the following topics: photons, electron-atom collisions; electron-molecule collisions; electron-ion collisions; collisions involving exotic species; ion- atom collisions, ion-molecule or atom-molecule collisions; atom-atom collisions; ion-ion collisions; collisions involving rydberg atoms; field assisted collisions; collisions involving clusters and collisions involving condensed matter.

  15. CURRICULUM GUIDES IN PHYSICS--GENERAL ADVANCED PLACEMENT, COLLEGE LEVEL.

    ERIC Educational Resources Information Center

    WESNER, GORDON E.

    THE GENERAL PHYSICS CURRICULUM IS PLANNED FOR THOSE WHOSE GENERAL ABILITY IS BETTER THAN AVERAGE AND IS OFFERED IN GRADES 11 OR 12. GENERAL OBJECTIVES ARE, TO DEVELOP CRITICAL THINKING THROUGH THE SCIENTIFIC METHOD, TO UNDERSTAND BASIC PHYSICAL LAWS AND MAN'S PLACE IN THE UNIVERSE, AND TO DEVELOP A SCIENTIFIC ABILITY AND INTEREST. ELEVEN UNITS OF…

  16. Physics of our Days: Cooling and thermometry of atomic Fermi gases

    NASA Astrophysics Data System (ADS)

    Onofrio, R.

    2017-02-01

    We review the status of cooling techniques aimed at achieving the deepest quantum degeneracy for atomic Fermi gases. We first discuss some physics motivations, providing a quantitative assessment of the need for deep quantum degeneracy in relevant physics cases, such as the search for unconventional superfluid states. Attention is then focused on the most widespread technique to reach deep quantum degeneracy for Fermi systems, sympathetic cooling of Bose–Fermi mixtures, organizing the discussion according to the specific species involved. Various proposals to circumvent some of the limitations on achieving the deepest Fermi degeneracy, and their experimental realizations, are then reviewed. Finally, we discuss the extension of these techniques to optical lattices and the implementation of precision thermometry crucial to the understanding of the phase diagram of classical and quantum phase transitions in Fermi gases.

  17. Atomic layer deposition of metal oxide patterns on nonwoven fiber mats using localized physical compression.

    PubMed

    Sweet, William J; Oldham, Christopher J; Parsons, Gregory N

    2014-06-25

    Patterning is an essential part of many industrial processes from printing to semiconductor manufacturing. In this work, we demonstrate a new method to pattern and selectively coat nonwoven textiles by atomic layer deposition (ALD) using compressive mask patterning. A physical mask combined with mechanical compression allows lateral definition and fidelity of the ALD coating to be controlled. We produce features of several sizes on different nonwoven fiber materials and demonstrate the ability to limit diffusion effects to within <200 μm of the pattern edge. Lateral and vertical penetration of reactive growth species into nonwoven mats is investigated by plan-view and cross-sectional imaging. Vertical growth is also analyzed by imaging coating depth into fiber mat stacks. We develop a fully quantitative transport model that describes well the effect of fiber structure and mechanical compression on the extent of coating under the physical mask. This method could be implemented for high-volume patterning for applications including flexible electronics.

  18. Atom Interferometry

    ScienceCinema

    Mark Kasevich

    2016-07-12

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton’s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  19. Atom Interferometry

    SciTech Connect

    Kasevich, Mark

    2008-05-08

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton's constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gyroscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be used to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  20. Atom Interferometry

    SciTech Connect

    Mark Kasevich

    2008-05-07

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton’s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  1. Atomic physics and synchrotron radiation: The production and accumulation of highly charged ions

    SciTech Connect

    Johnson, B.M.; Meron, M.; Agagu, A.; Jones, K.W.

    1986-01-01

    Synchrotron radiation can be used to produce highly-charged ions, and to study photoexcitation and photoionization for ions of virtually any element in the periodic table. To date, with few exceptions, atomic physics studies have been limited to rare gases and a few metal vapors, and to photoexcitation energies in the VUV region of the electromagnetic spectrum. These limitations can now be overcome using photons produced by high-brightness synchrotron storage rings, such as the x-ray ring at the National Synchrotron Light Source (NSLS) at Brookhaven. Furthermore, calculations indicate that irradiation of an ion trap with an intense energetic photon beam will result in a viable source of highly-charged ions that can be given the name PHOBIS: the PHOton Beam Ion Source. Promising results, which encourage the wider systematic use of synchrotron radiation in atomic physics research, have been obtained in recent experiments on VUV photoemission and the production and storage of multiply-charged ions. 26 refs., 4 figs., 1 tab.

  2. Teachers' Views about the Nuffield Advanced Physics Course.

    ERIC Educational Resources Information Center

    Tebbutt, M. J.

    1981-01-01

    Summarizes results of a survey on teachers' views of the Nuffield A-level physics course (NAP) including, among others, course content, philosophy, examinations, organization, and individual units. Suggests that most teachers surveyed were satisfied with their NAP course. (SK)

  3. Engineering design and analysis of advanced physical fine coal cleaning technologies

    SciTech Connect

    Not Available

    1992-01-20

    This project is sponsored by the United States Department of Energy (DOE) for the Engineering Design and Analysis of Advanced Physical Fine Coal Cleaning Technologies. The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies-heavy-liquid cylconing, selective agglomeration, and advanced froth flotation through the proof-of-concept (POC) level.

  4. Advances in the physics basis for the European DEMO design

    NASA Astrophysics Data System (ADS)

    Wenninger, R.; Arbeiter, F.; Aubert, J.; Aho-Mantila, L.; Albanese, R.; Ambrosino, R.; Angioni, C.; Artaud, J.-F.; Bernert, M.; Fable, E.; Fasoli, A.; Federici, G.; Garcia, J.; Giruzzi, G.; Jenko, F.; Maget, P.; Mattei, M.; Maviglia, F.; Poli, E.; Ramogida, G.; Reux, C.; Schneider, M.; Sieglin, B.; Villone, F.; Wischmeier, M.; Zohm, H.

    2015-06-01

    In the European fusion roadmap, ITER is followed by a demonstration fusion power reactor (DEMO), for which a conceptual design is under development. This paper reports the first results of a coherent effort to develop the relevant physics knowledge for that (DEMO Physics Basis), carried out by European experts. The program currently includes investigations in the areas of scenario modeling, transport, MHD, heating & current drive, fast particles, plasma wall interaction and disruptions.

  5. Advanced Physical Models and Numerical Methods for High Enthalpy and Plasma Flows Applied to Hypersonics

    DTIC Science & Technology

    2011-07-28

    nonequilibrium. For example, the plasma transport may transition between rarefied and continuum flow , requiring appropriate models for each case through...AFRL-AFOSR-UK-TR-2011-0023 Advanced Physical Models and Numerical Methods for High Enthalpy and Plasma Flows Applied to Hypersonics...2010 4. TITLE AND SUBTITLE Advanced Physical Models and Numerical Methods for High Enthalpy and Plasma Flows Applied to Hypersonics 5a

  6. SOARCA Peach Bottom Atomic Power Station Long-Term Station Blackout Uncertainty Analysis: Knowledge Advancement.

    SciTech Connect

    Gauntt, Randall O.; Mattie, Patrick D.; Bixler, Nathan E.; Ross, Kyle; Cardoni, Jeffrey N; Kalinich, Donald A.; Osborn, Douglas M.; Sallaberry, Cedric Jean-Marie; Ghosh, S. Tina

    2014-02-01

    This paper describes the knowledge advancements from the uncertainty analysis for the State-of- the-Art Reactor Consequence Analyses (SOARCA) unmitigated long-term station blackout accident scenario at the Peach Bottom Atomic Power Station. This work assessed key MELCOR and MELCOR Accident Consequence Code System, Version 2 (MACCS2) modeling uncertainties in an integrated fashion to quantify the relative importance of each uncertain input on potential accident progression, radiological releases, and off-site consequences. This quantitative uncertainty analysis provides measures of the effects on consequences, of each of the selected uncertain parameters both individually and in interaction with other parameters. The results measure the model response (e.g., variance in the output) to uncertainty in the selected input. Investigation into the important uncertain parameters in turn yields insights into important phenomena for accident progression and off-site consequences. This uncertainty analysis confirmed the known importance of some parameters, such as failure rate of the Safety Relief Valve in accident progression modeling and the dry deposition velocity in off-site consequence modeling. The analysis also revealed some new insights, such as dependent effect of cesium chemical form for different accident progressions. (auth)

  7. ENHANCING THE ATOMIC-LEVEL UNDERSTANDING OF CO2 MINERAL SEQUESTRATION MECHANISMS VIA ADVANCED COMPUTATIONAL MODELING

    SciTech Connect

    A.V.G. Chizmeshya; M.J. McKelvy; G.H. Wolf; R.W. Carpenter; D.A. Gormley; J.R. Diefenbacher; R. Marzke

    2006-03-01

    significantly improved our understanding of mineral carbonation. Group members at the Albany Research Center have recently shown that carbonation of olivine and serpentine, which naturally occurs over geological time (i.e., 100,000s of years), can be accelerated to near completion in hours. Further process refinement will require a synergetic science/engineering approach that emphasizes simultaneous investigation of both thermodynamic processes and the detailed microscopic, atomic-level mechanisms that govern carbonation kinetics. Our previously funded Phase I Innovative Concepts project demonstrated the value of advanced quantum-mechanical modeling as a complementary tool in bridging important gaps in our understanding of the atomic/molecular structure and reaction mechanisms that govern CO2 mineral sequestration reaction processes for the model Mg-rich lamellar hydroxide feedstock material Mg(OH)2. In the present simulation project, improved techniques and more efficient computational schemes have allowed us to expand and augment these capabilities and explore more complex Mg-rich, lamellar hydroxide-based feedstock materials, including the serpentine-based minerals. These feedstock materials are being actively investigated due to their wide availability, and low-cost CO2 mineral sequestration potential. Cutting-edge first principles quantum chemical, computational solid-state and materials simulation methodology studies proposed herein, have been strategically integrated with our new DOE supported (ASU-Argonne National Laboratory) project to investigate the mechanisms that govern mineral feedstock heat-treatment and aqueous/fluid-phase serpentine mineral carbonation in situ. This unified, synergetic theoretical and experimental approach has provided a deeper understanding of the key reaction mechanisms than either individual approach can alone. We used ab initio techniques to significantly advance our understanding of atomic-level processes at the solid/solution interface by

  8. ENHANCING THE ATOMIC-LEVEL UNDERSTANDING OF CO2 MINERAL SEQUESTRATION MECHANISMS VIA ADVANCED COMPUTATIONAL MODELING

    SciTech Connect

    A.V.G. Chizmeshya

    2003-12-19

    /NETL managed National Mineral Sequestration Working Group we have already significantly improved our understanding of mineral carbonation. Group members at the Albany Research Center have recently shown that carbonation of olivine and serpentine, which naturally occurs over geological time (i.e., 100,000s of years), can be accelerated to near completion in hours. Further process refinement will require a synergetic science/engineering approach that emphasizes simultaneous investigation of both thermodynamic processes and the detailed microscopic, atomic-level mechanisms that govern carbonation kinetics. Our previously funded Phase I Innovative Concepts project demonstrated the value of advanced quantum-mechanical modeling as a complementary tool in bridging important gaps in our understanding of the atomic/molecular structure and reaction mechanisms that govern CO{sub 2} mineral sequestration reaction processes for the model Mg-rich lamellar hydroxide feedstock material Mg(OH){sub 2}. In the present simulation project, improved techniques and more efficient computational schemes have allowed us to expand and augment these capabilities and explore more complex Mg-rich, lamellar hydroxide-based feedstock materials, including the serpentine-based minerals. These feedstock materials are being actively investigated due to their wide availability, and low-cost CO{sub 2} mineral sequestration potential. Cutting-edge first principles quantum chemical, computational solid-state and materials simulation methodology studies proposed herein, have been strategically integrated with our new DOE supported (ASU-Argonne National Laboratory) project to investigate the mechanisms that govern mineral feedstock heat-treatment and aqueous/fluid-phase serpentine mineral carbonation in situ. This unified, synergetic theoretical and experimental approach will provide a deeper understanding of the key reaction mechanisms than either individual approach can alone. Ab initio techniques will also

  9. ENHANCING THE ATOMIC-LEVEL UNDERSTANDING OF CO2 MINERAL SEQUESTRATION MECHANISMS VIA ADVANCED COMPUTATIONAL MODELING

    SciTech Connect

    A.V.G. Chizmeshya

    2002-12-19

    /NETL managed National Mineral Sequestration Working Group we have already significantly improved our understanding of mineral carbonation. Group members at the Albany Research Center have recently shown that carbonation of olivine and serpentine, which naturally occurs over geological time (i.e., 100,000s of years), can be accelerated to near completion in hours. Further process refinement will require a synergetic science/engineering approach that emphasizes simultaneous investigation of both thermodynamic processes and the detailed microscopic, atomic-level mechanisms that govern carbonation kinetics. Our previously funded Phase I Innovative Concepts project demonstrated the value of advanced quantum-mechanical modeling as a complementary tool in bridging important gaps in our understanding of the atomic/molecular structure and reaction mechanisms that govern CO{sub 2} mineral sequestration reaction processes for the model Mg-rich lamellar hydroxide feedstock material Mg(OH){sub 2}. In the present simulation project, improved techniques and more efficient computational schemes have allowed us to expand and augment these capabilities and explore more complex Mg-rich, lamellar hydroxide-based feedstock materials, including the serpentine-based minerals. These feedstock materials are being actively investigated due to their wide availability, and low-cost CO{sub 2} mineral sequestration potential. Cutting-edge first principles quantum chemical, computational solid-state and materials simulation methodology studies proposed herein, have been strategically integrated with our new DOE supported (ASU-Argonne National Laboratory) project to investigate the mechanisms that govern mineral feedstock heat-treatment and aqueous/fluid-phase serpentine mineral carbonation in situ. This unified, synergetic theoretical and experimental approach will provide a deeper understanding of the key reaction mechanisms than either individual approach can alone. Ab initio techniques will also

  10. The Efficacy of Advance Organizers and Behavioral Objectives for Improving Achievement in Physics.

    ERIC Educational Resources Information Center

    Hershman, Kenneth Eugene

    This research investigates the utility of advance organizers and behavioral objectives in a traditional introductory physics class at the college level. The advance organizer was designed to compare and contrast content to be learned with content previously studied or with assumed common knowledge. Behavioral objectives listed the expected…

  11. Recent Advances in Indirect Drive ICF Target Physics

    SciTech Connect

    Hammel, B; Lindl, J; Amendt, P A; Bernat, G W; Collins, G W; Glenzer, S H; Koch, S H; Haan, S; Landen, O L; Suter, L J

    2002-10-08

    In preparation for ignition on the National Ignition Facility, the Lawrence Livermore National Laboratory's Inertial Confinement Fusion Program, working in collaboration with Los Alamos National Laboratory, Commissariat a lEnergie Atomique (CEA), and Laboratory for Laser Energetics at the University of Rochester, has performed a broad range of experiments on the Nova and Omega lasers to test the fundamentals of the NIF target designs. These studies have refined our understanding of the important target physics, and have led to many of the specifications for the NIF laser and the cryogenic ignition targets. Our recent work has been focused in the areas of hohlraum energetics, symmetry, shock physics, and target design optimization & fabrication.

  12. Recent advances in indirect drive ICF target physics at LLNL

    SciTech Connect

    Bernat, T P; Collins, G W; Haan, S; Hammel, B A; Landen, O L; MacGowan, B J; Sutter, L J

    1998-01-13

    In preparation for ignition on the National Ignition Facility, the Lawrence Livermore National Laboratory's Inertial Confinement Fusion Program, working in collaboration with Los Alamos National Laboratory, Commissariat a 1'Energie Atomique (CEA), and Laboratory for Laser Energetics at the University of Rochester, has performed a broad range of experiments on the Nova and Omega lasers to test the fundamentals of the NIF target designs. These studies have refined our understanding of the important target physics, and have led to many of the specifications for the NIF laser and the cryogenic ignition targets. Our recent work has been focused in the areas of hohlraum energetics, symmetry, shock physics, and target design optimization & fabrication.

  13. Working with Advanced Primary School Students in Physics

    NASA Astrophysics Data System (ADS)

    Jankovic, Ljiljana; Cucic, Dragoljub

    2010-01-01

    Working with students who have special needs is the type of work that requires special engagement and skills of those who perform it. Working with gifted children requires outstanding knowledge of a teacher and above all the teachers should be very well informed on the subject they teach, Physics in our case. This work also requires great pedagogical and psychological skills so that these talented students would be approached in a suitable way. In this paper we will present to you our methods of teaching Physics to these talented children (13 years old), in the Regional Center for Talents "Mihajlo Pupin" in Pancevo.

  14. Advanced Ground Systems Maintenance Physics Models for Diagnostics Project

    NASA Technical Reports Server (NTRS)

    Harp, Janicce Leshay

    2014-01-01

    The project will use high-fidelity physics models and simulations to simulate real-time operations of cryogenic and systems and calculate the status/health of the systems. The project enables the delivery of system health advisories to ground system operators. The capability will also be used to conduct planning and analysis of cryogenic system operations.

  15. Advanced Quantitative Measurement Methodology in Physics Education Research

    ERIC Educational Resources Information Center

    Wang, Jing

    2009-01-01

    The ultimate goal of physics education research (PER) is to develop a theoretical framework to understand and improve the learning process. In this journey of discovery, assessment serves as our headlamp and alpenstock. It sometimes detects signals in student mental structures, and sometimes presents the difference between expert understanding and…

  16. Recent advances in understanding physical properties of metallurgical slags

    NASA Astrophysics Data System (ADS)

    Min, Dong Joon; Tsukihashi, Fumitaka

    2017-01-01

    Present-day knowledge of the structure and physical properties of metallurgical slags is summarized to address structure-property and inter-property relationships. Physical properties of slags including viscosity, electrical conductivity, and surface tension is reviewed focusing on the effect of slag structure, which is comprehensively evaluated using FT-IT, Raman, and MAS-NMR spectroscopy. The effect of the slag composition on slag structure and property is reviewed in detail: Compositional effect encompasses traditional concepts of basicity, network-forming behaviors of anions, and secondary impact of network-modifying cations. Secondary objective of this review is elucidating the mutual relationship between physical properties of slags. For instance, the relationship between slag viscosity and electrical conductivity is suggested by Walden's rule and discussed based on the experimental results. Slag foaming index is also introduced as a comprehensive understanding method of physical properties of slags. The dimensional analysis was made to address the effect of viscosity, density, and surface tension on the foaming index of slags.

  17. Relativistic Momentum-Space Equations with Applications to Atomic and Elementary Particle Physics

    NASA Astrophysics Data System (ADS)

    Hardekopf, Eugene Edward

    Relativistic equal-time wave equations obtained from field theory which describe bound states of N Dirac particles inevitably involve free or external-field positive -energy projection operators (LAMDA)(,+)(i). For N > 2 these operators are vital if the equations are to admit normaliz- able solutions. Such equations have been used in the past to obtain relativistic corrections to simple atomic systems, and to provide a theoretical basis for the Dirac-Hartree-Fock type of equations for many-electron atoms. These equations also find applications in ele- mentary particle physics in describing bound states of quarks. Here we initiate a numerical study of such equations, avoiding an expan- sion in powers of v/c. We work in momentum space, where the free projection operators are simple functions of (')p. We describe tech- niques for finding the eigenvalues and eigenfunctions of H(,+)(1,2) = h(,D)(1) + h(,D)(2) + (LAMDA)(,++)V(LAMDA)(,++) where h(,D)(i) is the free Dirac Hamiltonian and V is a local potential with either a (VBAR)(')r(,1)-(')r(,2)(VBAR)('-1) singularity in the case of atomic systems, or a (VBAR)(')r(,1)-(')r(,2)(VBAR) behavior plus a Coulomb-like singular- ity in the case of bound quarks. Results are presented for both pure Coulomb and a Coulomb plus Breit potential for the atomic case, and for a pure Lorentz scalar in the linear potential case. In the atomic case a wide range of m(,1)/m(,2) and coupling strength (gamma) is studied and the m(,2) = (INFIN) limit is compared with the Dirac equation. The magni- tude of level shifts associated with virtual pair production in such two-body systems is discussed. For intermediate values of (gamma) a com- parison is made between the numerical results and those of pertur- bation theory. We find that there can often be large corrections to perturbative results even for not terribly large values of v/c. We also study the strong coupling limit and find the value (gamma)(,max) for which the lowest-lying bound state

  18. Atomic physics and quantum optics using superconducting circuits: from the Dynamical Casimir effect to Majorana fermions

    NASA Astrophysics Data System (ADS)

    Nori, Franco

    2012-02-01

    This talk will present an overview of some of our recent results on atomic physics and quantum optics using superconducting circuits. Particular emphasis will be given to photons interacting with qubits, interferometry, the Dynamical Casimir effect, and also studying Majorana fermions using superconducting circuits.[4pt] References available online at our web site:[0pt] J.Q. You, Z.D. Wang, W. Zhang, F. Nori, Manipulating and probing Majorana fermions using superconducting circuits, (2011). Arxiv. J.R. Johansson, G. Johansson, C.M. Wilson, F. Nori, Dynamical Casimir effect in a superconducting coplanar waveguide, Phys. Rev. Lett. 103, 147003 (2009). [0pt] J.R. Johansson, G. Johansson, C.M. Wilson, F. Nori, Dynamical Casimir effect in superconducting microwave circuits, Phys. Rev. A 82, 052509 (2010). [0pt] C.M. Wilson, G. Johansson, A. Pourkabirian, J.R. Johansson, T. Duty, F. Nori, P. Delsing, Observation of the Dynamical Casimir Effect in a superconducting circuit. Nature, in press (Nov. 2011). P.D. Nation, J.R. Johansson, M.P. Blencowe, F. Nori, Stimulating uncertainty: Amplifying the quantum vacuum with superconducting circuits, Rev. Mod. Phys., in press (2011). [0pt] J.Q. You, F. Nori, Atomic physics and quantum optics using superconducting circuits, Nature 474, 589 (2011). [0pt] S.N. Shevchenko, S. Ashhab, F. Nori, Landau-Zener-Stuckelberg interferometry, Phys. Reports 492, 1 (2010). [0pt] I. Buluta, S. Ashhab, F. Nori. Natural and artificial atoms for quantum computation, Reports on Progress in Physics 74, 104401 (2011). [0pt] I.Buluta, F. Nori, Quantum Simulators, Science 326, 108 (2009). [0pt] L.F. Wei, K. Maruyama, X.B. Wang, J.Q. You, F. Nori, Testing quantum contextuality with macroscopic superconducting circuits, Phys. Rev. B 81, 174513 (2010). [0pt] J.Q. You, X.-F. Shi, X. Hu, F. Nori, Quantum emulation of a spin system with topologically protected ground states using superconducting quantum circuit, Phys. Rev. A 81, 063823 (2010).

  19. Project T.E.A.M. (Technical Education Advancement Modules). Introduction to Industrial Physics.

    ERIC Educational Resources Information Center

    Whisenhunt, James E.

    This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 20-hour introduction to industrial physics that explains and demonstrates to industrial maintenance mechanics the direct relationship of physics to machinery. Project TEAM is intended to upgrade basic technical competencies of…

  20. Influence of Halide Solutions on Collagen Networks: Measurements of Physical Properties by Atomic Force Microscopy

    PubMed Central

    Kempe, André; Lackner, Maximilian

    2016-01-01

    The influence of aqueous halide solutions on collagen coatings was tested. The effects on resistance against indentation/penetration on adhesion forces were measured by atomic force microscopy (AFM) and the change of Young's modulus of the coating was derived. Comparative measurements over time were conducted with halide solutions of various concentrations. Physical properties of the mesh-like coating generally showed large variability. Starting with a compact set of physical properties, data disperse after minutes. A trend of increase in elasticity and permeability was found for all halide solutions. These changes were largest in NaI, displaying a logical trend with ion size. However a correlation with concentration was not measured. Adhesion properties were found to be independent of mechanical properties. The paper also presents practical experience for AFM measurements of soft tissue under liquids, particularly related to data evaluation. The weakening in physical strength found after exposure to halide solutions may be interpreted as widening of the network structure or change in the chemical properties in part of the collagen fibres (swelling). In order to design customized surface coatings at optimized conditions also for medical applications, halide solutions might be used as agents with little impact on the safety of patients. PMID:27721994

  1. Integrating Advanced Physical Training Programs into the Marine Corps

    DTIC Science & Technology

    2009-02-20

    the CrossFit program and consequently a fee is required to participate in the CrossFit 3 P90X , Extreme Body Workout, (unknown... P90X , Extreme Body Workout n.d.) , P90X is a home based DVD workout program designed to achieve results in 90 days at a cost of $119.85. 4...PFT and is characterized by anaerobic (short burst) energy demands”.13 By coincidence, many of the advanced training programs, such as P90X , CrossFit

  2. Advances on modelling of ITER scenarios: physics and computational challenges

    NASA Astrophysics Data System (ADS)

    Giruzzi, G.; Garcia, J.; Artaud, J. F.; Basiuk, V.; Decker, J.; Imbeaux, F.; Peysson, Y.; Schneider, M.

    2011-12-01

    Methods and tools for design and modelling of tokamak operation scenarios are discussed with particular application to ITER advanced scenarios. Simulations of hybrid and steady-state scenarios performed with the integrated tokamak modelling suite of codes CRONOS are presented. The advantages of a possible steady-state scenario based on cyclic operations, alternating phases of positive and negative loop voltage, with no magnetic flux consumption on average, are discussed. For regimes in which current alignment is an issue, a general method for scenario design is presented, based on the characteristics of the poloidal current density profile.

  3. Advanced physical-chemical life support systems research

    NASA Technical Reports Server (NTRS)

    Evanich, Peggy L.

    1988-01-01

    A proposed NASA space research and technology development program will provide adequate data for designing closed loop life support systems for long-duration manned space missions. This program, referred to as the Pathfinder Physical-Chemical Closed Loop Life Support Program, is to identify and develop critical chemical engineering technologies for the closure of air and water loops within the spacecraft, surface habitats or mobility devices. Computerized simulation can be used both as a research and management tool. Validated models will guide the selection of the best known applicable processes and in the development of new processes. For the integration of the habitat system, a biological subsystem would be introduced to provide food production and to enhance the physical-chemical life support functions on an ever-increasing basis.

  4. Physical Chemistry Research Toward Proton Exchange Membrane Fuel Cell Advancement.

    PubMed

    Swider-Lyons, Karen E; Campbell, Stephen A

    2013-02-07

    Hydrogen fuel cells, the most common type of which are proton exchange membrane fuel cells (PEMFCs), are on a rapid path to commercialization. We credit physical chemistry research in oxygen reduction electrocatalysis and theory with significant breakthroughs, enabling more cost-effective fuel cells. However, most of the physical chemistry has been restricted to studies of platinum and related alloys. More work is needed to better understand electrocatalysts generally in terms of properties and characterization. While the advent of such highly active catalysts will enable smaller, less expensive, and more powerful stacks, they will require better understanding and a complete restructuring of the diffusion media in PEMFCs to facilitate faster transport of the reactants (O2) and products (H2O). Even Ohmic losses between materials become more important at high power. Such lessons from PEMFC research are relevant to other electrochemical conversion systems, including Li-air batteries and flow batteries.

  5. Advanced reactor physics methods for heterogeneous reactor cores

    NASA Astrophysics Data System (ADS)

    Thompson, Steven A.

    To maintain the economic viability of nuclear power the industry has begun to emphasize maximizing the efficiency and output of existing nuclear power plants by using longer fuel cycles, stretch power uprates, shorter outage lengths, mixed-oxide (MOX) fuel and more aggressive operating strategies. In order to accommodate these changes, while still satisfying the peaking factor and power envelope requirements necessary to maintain safe operation, more complexity in commercial core designs have been implemented, such as an increase in the number of sub-batches and an increase in the use of both discrete and integral burnable poisons. A consequence of the increased complexity of core designs, as well as the use of MOX fuel, is an increase in the neutronic heterogeneity of the core. Such heterogeneous cores introduce challenges for the current methods that are used for reactor analysis. New methods must be developed to address these deficiencies while still maintaining the computational efficiency of existing reactor analysis methods. In this thesis, advanced core design methodologies are developed to be able to adequately analyze the highly heterogeneous core designs which are currently in use in commercial power reactors. These methodological improvements are being pursued with the goal of not sacrificing the computational efficiency which core designers require. More specifically, the PSU nodal code NEM is being updated to include an SP3 solution option, an advanced transverse leakage option, and a semi-analytical NEM solution option.

  6. Making custom fiber lasers for use in an atomic physics experiment

    NASA Astrophysics Data System (ADS)

    Khademian, Ali; Cameron, Garnet; Nault, Kyla; Shiner, David

    2016-05-01

    Fiber lasers can be a reasonable choice for a laser source in atomic physics. Our particular applications involve the optical pumping and in some applications cooling of various transitions in atomic helium. Doped fiber with emission at the required wavelengths is necessary. Readily available fiber and approximate wavelength emission ranges include Yb (990 - 1150 nm), Er/Yb (1530 - 1625 nm) and Th (1900 -2100 nm). High efficiency conversion of pump photons into stable single frequency laser emission at the required wavelength is the function of the fiber laser. A simple fiber laser cavity uses a short (~ few mm) fiber grating high reflector mirror, a doped fiber section for the laser cavity, and a long (~ few cm) fiber grating output coupler. To ensure reliable single frequency operation, the laser cavity length should be within 2-3 times the output grating length. However the cavity length must be long enough for round trip gains to compensate for the output mirror transmission loss. Efficiency can be maximized by avoiding fiber splices in the fiber laser cavity. This requires that the gratings be written into the doped fiber directly. In our previous designs, back coupling of the fiber laser into the pump laser contributes to instability and sometimes caused catastrophic pump failure. Current designs use a fiber based wavelength splitter (WDM) to study and circumvent this problem. Data will be presented on the fiber lasers at 1083 nm. Work on a Thulium 2057 nm fiber laser will also be discussed. This work is supported by NSF Grant # 1404498.

  7. The Heidelberg test storage ring for heavy ions and its use for atomic physics

    SciTech Connect

    Schuch, R.

    1986-11-01

    A brief description of the Heavy-Ion Test Storage Ring (TSR) presently being built at the Max-Planck Institut in Heidelberg is given. It will be able to store ions injected from the tandem postaccelerator combination up to about 30 MeV/nucleon for a charge to mass ratio of 0.5. One of the main purposes of the TSR will be the study of electron cooling. Some atomic physics experiments are discussed using the electron cooling device which provides an electron-ion collision facility with good energy resolution and ion beams of high currents and low emittances. Here the possibilities for measurements of spontaneous and laser-induced radiative recombination and dielectronic recombination in the electron cooling section are discussed.

  8. A distributed, graphical user interface based, computer control system for atomic physics experiments

    NASA Astrophysics Data System (ADS)

    Keshet, Aviv; Ketterle, Wolfgang

    2013-01-01

    Atomic physics experiments often require a complex sequence of precisely timed computer controlled events. This paper describes a distributed graphical user interface-based control system designed with such experiments in mind, which makes use of off-the-shelf output hardware from National Instruments. The software makes use of a client-server separation between a user interface for sequence design and a set of output hardware servers. Output hardware servers are designed to use standard National Instruments output cards, but the client-server nature should allow this to be extended to other output hardware. Output sequences running on multiple servers and output cards can be synchronized using a shared clock. By using a field programmable gate array-generated variable frequency clock, redundant buffers can be dramatically shortened, and a time resolution of 100 ns achieved over effectively arbitrary sequence lengths.

  9. Advances in reactor physics education: Visualization of reactor parameters

    SciTech Connect

    Snoj, L.; Kromar, M.; Zerovnik, G.

    2012-07-01

    Modern computer codes allow detailed neutron transport calculations. In combination with advanced 3D visualization software capable of treating large amounts of data in real time they form a powerful tool that can be used as a convenient modern educational tool for reactor operators, nuclear engineers, students and specialists involved in reactor operation and design. Visualization is applicable not only in education and training, but also as a tool for fuel management, core analysis and irradiation planning. The paper treats the visualization of neutron transport in different moderators, neutron flux and power distributions in two nuclear reactors (TRIGA type research reactor and a typical PWR). The distributions are calculated with MCNP and CORD-2 computer codes and presented using Amira software. (authors)

  10. Optics and interferometry with atoms and molecules

    SciTech Connect

    Cronin, Alexander D.; Schmiedmayer, Joerg; Pritchard, David E.

    2009-07-15

    Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic clocks. Atom interferometry is now reaching maturity as a powerful art with many applications in modern science. In this review the basic tools for coherent atom optics are described including diffraction by nanostructures and laser light, three-grating interferometers, and double wells on atom chips. Scientific advances in a broad range of fields that have resulted from the application of atom interferometers are reviewed. These are grouped in three categories: (i) fundamental quantum science, (ii) precision metrology, and (iii) atomic and molecular physics. Although some experiments with Bose-Einstein condensates are included, the focus of the review is on linear matter wave optics, i.e., phenomena where each single atom interferes with itself.

  11. Effects of Solution Physical Properties on Copper and Chromium Signals in Flame Atomic Absorption Spectrometry

    NASA Astrophysics Data System (ADS)

    Rocha, Fàbio R. P.; Nòbrega, Joaquim A.

    1996-10-01

    Instrumental techniques, such as flame atomic absorption spectrometry (FAAS), are frequently used in chemical analysis. Independently of the technique used, the chemical principles must be considered to assure that the analytical results are correct. In FAAS, the most critical step is the sample introduction, since solutions need to be converted in an aerosol (nebulization process) that should contain drops with suitable size to attain the flame. Solution physical properties, such as viscosity and surface tension, can severely affect the analytical signals. Solutions with high viscosity are less easily aspirated and the analyte mass that reach the flame is reduced. The surface tension of the solution affects the size of the drops generated by the nebulization process and can modify the quantity of analyte that attain the flame. This work describes an experiment that allow demonstrating the effects of viscosity and surface tension on analytical signals, using a set of copper solutions prepared in different concentrations of ethanol and chromium solutions prepared in surfactant (tetrapropylammonium bromide) medium. The experiment can be carried out in a 4 h laboratory class and is useful to demonstrate to undergraduate students the effects of samples physical properties on the analytical signals in FAAS.

  12. Advanced physical fine coal cleaning spherical agglomeration. Final report

    SciTech Connect

    Not Available

    1990-09-01

    The project included process development, engineering, construction, and operation of a 1/3 tph proof-of-concept (POC) spherical agglomeration test module. The POC tests demonstrated that physical cleaning of ultrafine coal by agglomeration using heptane can achieve: (1) Pyritic sulfur reductions beyond that possible with conventional coal cleaning methods; (2) coal ash contents below those which can be obtained by conventional coal cleaning methods at comparable energy recoveries; (3) energy recoveries of 80 percent or greater measured against the raw coal energy content; (4) complete recovery of the heptane bridging liquid from the agglomerates; and (5) production of agglomerates with 3/8-inch size and less than 30 percent moisture. Test results met or exceeded all of the program objectives. Nominal 3/8-inch size agglomerates with less than 20 percent moisture were produced. The clean coal ash content varied between 1.5 to 5.5 percent by weight (dry basis) depending on feed coal type. Ash reductions of the run-of-mine (ROM) coal were 77 to 83 percent. ROM pyritic sulfur reductions varied from 86 to 90 percent for the three test coals, equating to total sulfur reductions of 47 to 72 percent.

  13. Advances in computed radiography systems and their physical imaging characteristics.

    PubMed

    Cowen, A R; Davies, A G; Kengyelics, S M

    2007-12-01

    Radiological imaging is progressing towards an all-digital future, across the spectrum of medical imaging techniques. Computed radiography (CR) has provided a ready pathway from screen film to digital radiography and a convenient entry point to PACS. This review briefly revisits the principles of modern CR systems and their physical imaging characteristics. Wide dynamic range and digital image enhancement are well-established benefits of CR, which lend themselves to improved image presentation and reduced rates of repeat exposures. However, in its original form CR offered limited scope for reducing the radiation dose per radiographic exposure, compared with screen film. Recent innovations in CR, including the use of dual-sided image readout and channelled storage phosphor have eased these concerns. For example, introduction of these technologies has improved detective quantum efficiency (DQE) by approximately 50 and 100%, respectively, compared with standard CR. As a result CR currently affords greater scope for reducing patient dose, and provides a more substantive challenge to the new solid-state, flat-panel, digital radiography detectors.

  14. Where the girls aren't: High school girls and advanced placement physics enrollment

    NASA Astrophysics Data System (ADS)

    Barton, Susan O'brien

    During the high school years, when many students first have some choice in course selection, research indicates that girls choose to enroll in more math and science courses, take more advanced placement courses, and take more honors courses in English, biology, chemistry, mathematics, and foreign languages than ever before. Yet, not only are boys more likely to take all of the three core science courses (biology, chemistry, and physics), boys enroll in advanced placement physics approximately three times as often as do girls. This study examines the perceptions, attitudes, and aspirations of thirty high school girls enrolled in senior-level science electives in an attempt to understand their high school science course choices, and what factors were influencing them. This is a qualitative investigation employing constructivist grounded theory methods. There are two main contributions of this study. First, it presents a new conceptual and analytical framework to investigate the problem of why some high school girls do not enroll in physics coursework. This framework is grounded in the data and is comprised of three existing feminist perspectives along the liberal/radical continuum of feminist thought. Second, this study illuminates a complex set of reasons why participants avoided high school physics (particularly advanced placement physics) coursework. These reasons emerged as three broad categories related to: (a) a lack of connectedness with physics curriculum and instruction; (b) prior negative experiences with physics and math classroom climates; and (c) future academic goals and career aspirations. Taken together, the findings of this study indicate that the problem of high school girls and physics enrollment---particularly advanced placement physics enrollment---is a problem that cannot be evaluated or considered from one perspective.

  15. Advanced Experiments in Nuclear Science, Volume I: Advanced Nuclear Physics and Chemistry Experiments.

    ERIC Educational Resources Information Center

    Duggan, Jerome L.; And Others

    The experiments in this manual represent state-of-the-art techniques which should be within the budgetary constraints of a college physics or chemistry department. There are fourteen experiments divided into five modules. The modules are on X-ray fluorescence, charged particle detection, neutron activation analysis, X-ray attenuation, and…

  16. Getting Physical with Your Chemistry: Mechanically Investigating Local Structure and Properties of Surfaces with the Atomic Force Microscope

    ERIC Educational Resources Information Center

    Heinz, William F.; Hoh, Jan H.

    2005-01-01

    Atomic force microscope (AFM) investigates mechanically the chemical properties of individual molecules, surfaces, and materials using suitably designed probes. The current state of the art of AFM in terms of imaging, force measurement, and sample manipulation and its application to physical chemistry is discussed.

  17. Introduction to the Contributions of A. Temkin and R. J. Drachman to Atomic Physics

    NASA Technical Reports Server (NTRS)

    Bhatia, A.K.

    2007-01-01

    Their work, as is the work of most atomic theorists, is concerned with solving the Schroedinger equation accurately for wave function in cases where there is no exact analytical solution. In particular, Temkin is associated with electron scattering from atoms and ions. When he started there already were a number of methods to study the scattering of electrons from atoms.

  18. Proceedings of the 1992 topical meeting on advances in reactor physics. Volume 2

    SciTech Connect

    Not Available

    1992-04-01

    This document, Volume 2, presents proceedings of the 1992 Topical Meeting on Advances in Reactor Physics on March 8--11, 1992 at Charleston, SC. Session topics were as follows: Transport Theory; Fast Reactors; Plant Analyzers; Integral Experiments/Measurements & Analysis; Core Computational Systems; Reactor Physics; Monte Carlo; Safety Aspects of Heavy Water Reactors; and Space-Time Core Kinetics. The individual reports have been cataloged separately. (FI)

  19. Probing the scale of new physics by Advanced LIGO/VIRGO

    NASA Astrophysics Data System (ADS)

    Dev, P. S. Bhupal; Mazumdar, A.

    2016-05-01

    We show that if the new physics beyond the standard model is associated with a first-order phase transition around 107- 108 GeV , the energy density stored in the resulting stochastic gravitational waves and the corresponding peak frequency are within the projected final sensitivity of the advanced LIGO/VIRGO detectors. We discuss some possible new physics scenarios that could arise at such energies, and in particular, the consequences for Peccei-Quinn and supersymmetry breaking scales.

  20. A physical approach to reduce nonspecific adhesion in molecular recognition atomic force microscopy.

    PubMed

    Willemsen, O H; Snel, M M; Kuipers, L; Figdor, C G; Greve, J; De Grooth, B G

    1999-02-01

    Atomic force microscopy is one of the few techniques that allow analysis of biological recognition processes at the single-molecule level. A major limitation of this approach is the nonspecific interaction between the force sensor and substrate. We have modeled the nonspecific interaction by looking at the interaction potential between a conical Si3N4 tip with a spherical end face and a mica surface in solution, using DLVO (Derjaguin, Landau, Verwey, Overbeek) theory and numerical calculations. Insertion of the tip-sample potential in a simulation of an approach-retract cycle of the cantilever gives the well-known force-distance curve. Simulating a force-distance curve at low salt concentration predicts a discrete hopping of the tip, caused by thermal fluctuations. This hopping behavior was observed experimentally and gave rise to a novel approach to making measurements in adhesion mode that essentially works in the repulsive regime. The distance between tip and sample will still be small enough to allow spacer-involved specific interactions, and the percentage of nonspecific interactions of the bare tip with the mica is minimized. We have validated this physical model by imaging intercellular adhesion molecule 1 (ICAM-1) antigen with a tip functionalized with anti-ICAM-1 antibody. The measurement demonstrated that a significant decrease in the number of nonspecific interactions was realized, and the topographical image quality and the specific bonding capability of the tip were not affected.

  1. Protein model refinement using an optimized physics-based all-atom force field.

    PubMed

    Jagielska, Anna; Wroblewska, Liliana; Skolnick, Jeffrey

    2008-06-17

    One of the greatest challenges in protein structure prediction is the refinement of low-resolution predicted models to high-resolution structures that are close to the native state. Although contemporary structure prediction methods can assemble the correct topology for a large fraction of protein domains, such approximate models are often not of the resolution required for many important applications, including studies of reaction mechanisms and virtual ligand screening. Thus, the development of a method that could bring those structures closer to the native state is of great importance. We recently optimized the relative weights of the components of the Amber ff03 potential on a large set of decoy structures to create a funnel-shaped energy landscape with the native structure at the global minimum. Such an energy function might be able to drive proteins toward their native structure. In this work, for a test set of 47 proteins, with 100 decoy structures per protein that have a range of structural similarities to the native state, we demonstrate that our optimized potential can drive protein models closer to their native structure. Comparing the lowest-energy structure from each trajectory with the starting decoy, structural improvement is seen for 70% of the models on average. The ability to do such systematic structural refinements by using a physics-based all-atom potential represents a promising approach to high-resolution structure prediction.

  2. Atomic and molecular physics of plasma-based environmental technologies for abatement of volatile organic compounds

    SciTech Connect

    Penetrante, B.M.; Hsiao, M.C.; Bardsley, J.N.; Merritt, B.T.; Vogtlin, G.E.; Kuthi, A.; Burkhart, C.P.; Bayless, J.R.

    1996-08-01

    Non-thermal plasma techniques represent a new generation of air emission control technology that potentially could treat large-volume emissions containing dilute concentrations of volatile organic compounds (VOCs). In order to apply non-thermal plasmas in an industrial scale, it is important to establish the electrical power requirements and byproducts of the process. There is a need for reliable data concerning the primary decomposition mechanisms and subsequent chemical kinetics associated with non-thermal processing of VOCs. There are many basic atomic and molecular physics issues that are essential in evaluating the economic performance of non- thermal plasma reactors. These studies are important in understanding how the input electrical power is dissipated in the plasma and how efficiently it is converted to the production of the plasma species (radicals, ions, or electrons) responsible for the decomposition of the VOCs. This paper will present results from the basic experimental and theoretical studies aimed at identifying the reaction mechanisms responsible for the primary decomposition of various types of VOCs.

  3. Recent advances in the link between physical activity, sedentary behavior, physical fitness, and colorectal cancer

    PubMed Central

    Namasivayam, Vikneswaran; Lim, Sam

    2017-01-01

    Physical inactivity is a well-established risk factor for colorectal cancer (CRC). Recent studies have characterized physical activity (PA), sedentary behavior, and cardiorespiratory fitness as distinct, interrelated constructs that influence the risk of CRC and related outcomes. PA levels required to confer protection against CRC may be higher than previously thought. Sedentary behavior, defined as time spent sitting, increases CRC risk independent of PA and may require novel interventions distinct from those targeting PA. Finally, cardiorespiratory fitness is inversely associated with CRC risk and mortality and may provide a potential tool for risk stratification and intervention. PMID:28344777

  4. Atomic step-and-terrace surface of polyimide sheet for advanced polymer substrate engineering

    NASA Astrophysics Data System (ADS)

    Tan, G.; Shimada, K.; Nozawa, Y.; Kaneko, S.; Urakami, T.; Koyama, K.; Komura, M.; Matsuda, A.; Yoshimoto, M.

    2016-07-01

    Typical thermostable and flexible polyimide polymers exhibit many excellent properties such as strong mechanical and chemical resistance. However, in contrast to single-crystal substrates like silicon or sapphire, polymers mostly display disordered and rough surfaces, which may result in instability and degradation of the interfaces between thin films and polymer substrates. As a step toward the development of next-generation polymer substrates, we here report single-atom-layer imprinting onto the polyimide sheets, resulting in an ultrasmooth 0.3 nm high atomic step-and-terrace surface on the polyimides. The ultrasmooth polymer substrates are expected to be applied to the fabrication of nanostructures such as superlattices, nanowires, or quantum dots in nanoscale-controlled electronic devices. We fabricate smooth and atomically stepped indium tin oxide transparent conducting oxide thin films on the imprinted polyimide sheets for future use in organic-based optoelectronic devices processed with nanoscale precision. Furthermore, toward 2D polymer substrate nanoengineering, we demonstrate nanoscale letter writing on the atomic step-and-terrace polyimide surface via atomic force microscopy probe scratching.

  5. Short Animation Movies as Advance Organizers in Physics Teaching: A Preliminary Study

    ERIC Educational Resources Information Center

    Koscianski, Andre; Ribeiro, Rafael Joao; da Silva, Sani Carvalho Rutz

    2012-01-01

    Background: Advance organizers are instructional materials that help students use previous knowledge to make links with new information. Short animation movies are a possible format and are well suited for physics, as they can portray dynamic phenomena and represent abstract concepts. Purpose: The study aimed to determine guidelines for the…

  6. Advanced Swimming, Phase One--Swimmer; Physical Education: 5551.48.

    ERIC Educational Resources Information Center

    Gutting, Dick

    GRADES OR AGES: Grades 7-12. SUBJECT MATTER: Advanced swimming. ORGANIZATION AND PHYSICAL APPEARANCE: The first five sections of the guide list course guidelines, course description, broad goal statement, behavioral objectives, course content, learning activities, and teaching procedures. The guide also contains evaluation forms and a five-item…

  7. Physical Features of Soil: Advanced Crop and Soil Science. A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    The course of study represents the second of six modules in advanced crop and soil science and introduces the agriculture student to the subject of physical features of the soil. Upon completing the two day lesson, the student will be able to determine the texture and structural types of soil, list the structural classes of the soil and where they…

  8. Folding peptides and proteins with all-atom physics: methods and applications

    NASA Astrophysics Data System (ADS)

    Shell, M. Scott

    2008-03-01

    Computational methods offer powerful tools for investigating proteins and peptides at the molecular-level; however, it has proven challenging to reproduce the long time scale folding processes of these molecules at a level that is both faithful to the atomic driving forces and attainable with modern commodity cluster computing. Alternatively, the past decade has seen significant progress in using bioinformatics-based approaches to infer the three dimensional native structures of proteins, drawing upon extensive knowledge databases of known protein structures [1]. These methods work remarkably well when a homologous protein can be found to provide a structural template for a candidate sequence. However, in cases where homology to database proteins is low, where the folding pathway is of interest, or where conformational flexibility is substantial---as in many emerging protein and peptide technologies---bioinformatics methods perform poorly. There is therefore great interest in seeing purely physics-based approaches succeed. We discuss a purely physics-based, database-free folding method, relying on proper thermal sampling (replica exchange molecular dynamics) and molecular potential energy functions. In order to surmount the tremendous computational demands of all-atom folding simulations, our approach implements a conformational search strategy based on a putative protein folding mechanism called zipping and assembly [2-4]. That is, we explicitly seek out potential folding pathways inferred from short simulations, and iteratively pursue all such routes by coaxing a polypeptide chain along them. The method is called the Zipping and Assembly Method (ZAM) and it works in two parts: (1) the full polypeptide chain is broken into small fragments that are first simulated independently and then successively re-assembled into larger segments with further sampling, and (2) consistently stable structure in fragments is detected and locked into place, in order to avoid re

  9. Building an advanced climate model: Program plan for the CHAMMP (Computer Hardware, Advanced Mathematics, and Model Physics) Climate Modeling Program

    SciTech Connect

    Not Available

    1990-12-01

    The issue of global warming and related climatic changes from increasing concentrations of greenhouse gases in the atmosphere has received prominent attention during the past few years. The Computer Hardware, Advanced Mathematics, and Model Physics (CHAMMP) Climate Modeling Program is designed to contribute directly to this rapid improvement. The goal of the CHAMMP Climate Modeling Program is to develop, verify, and apply a new generation of climate models within a coordinated framework that incorporates the best available scientific and numerical approaches to represent physical, biogeochemical, and ecological processes, that fully utilizes the hardware and software capabilities of new computer architectures, that probes the limits of climate predictability, and finally that can be used to address the challenging problem of understanding the greenhouse climate issue through the ability of the models to simulate time-dependent climatic changes over extended times and with regional resolution.

  10. How gender and reformed introductory physics impacts student success in advanced physics courses and continuation in the physics major

    NASA Astrophysics Data System (ADS)

    Rodriguez, Idaykis; Potvin, Geoff; Kramer, Laird H.

    2016-12-01

    [This paper is part of the Focused Collection on Gender in Physics.] Active-learning approaches to teaching introductory physics have been found to improve student learning and affective gains on short-term outcomes [S. Freeman et al., Proc. Natl. Acad. Sci. U.S.A. 111, 8410 (2014)]; however, whether or not the benefits of active learning impact women to the same degree as men has been a point of concern [A. Madsen, S. B. McKagan, and E. C. Sayre, Phys. Rev. ST Phys. Educ. Res. 9, 020121 (2013)]. Further, the long-term impacts of active-learning experiences are also understudied. At Florida International University, a Hispanic-majority institution, we have implemented Modeling Instruction (MI) and the Integrated Science Learning Environment (ISLE) in introductory physics classes for the past decade. In this empirical paper, we report on a longitudinal investigation of student performance and persistence in upper level physics courses after having previously experienced MI or ISLE in their introductory physics courses, and disaggregate students by gender. Using survival analysis methods, we find women who declare physics as a major are more likely than men to graduate with a physics degree. Women are also just as likely as men to pass through the upper division courses, with the highest failure risk for both men and women occurring in the first semester of upper-division course taking. These results reinforce the need to expand considerations of performance outcomes to be longitudinal to measure the effectiveness of the entire physics experience.

  11. Advanced multiconfiguration methods for complex atoms: I. Energies and wave functions

    NASA Astrophysics Data System (ADS)

    Froese Fischer, Charlotte; Godefroid, Michel; Brage, Tomas; Jönsson, Per; Gaigalas, Gediminas

    2016-09-01

    Multiconfiguration wave function expansions combined with configuration interaction methods are a method of choice for complex atoms where atomic state functions are expanded in a basis of configuration state functions. Combined with a variational method such as the multiconfiguration Hartree-Fock (MCHF) or multiconfiguration Dirac-Hartree-Fock (MCDHF), the associated set of radial functions can be optimized for the levels of interest. The present review updates the variational MCHF theory to include MCDHF, describes the multireference single and double process for generating expansions and the systematic procedure of a computational scheme for monitoring convergence. It focuses on the calculations of energies and wave functions from which other atomic properties can be predicted such as transition rates, hyperfine structures and isotope shifts, for example.

  12. Recent advances in transition metal-catalyzed N -atom transfer reactions of azides

    PubMed Central

    Driver, Tom G.

    2011-01-01

    Transition metal-catalyzed N-atom transfer reactions of azides provide efficient ways to construct new carbon–nitrogen and sulfur–nitrogen bonds. These reactions are inherently green: no additive besides catalyst is needed to form the nitrenoid reactive intermediate, and the by-product of the reaction is environmentally benign N2 gas. As such, azides can be useful precursors for transition metal-catalyzed N-atom transfer to sulfides, olefins and C–H bonds. These methods offer competitive selectivities and comparable substrate scope as alternative processes to generate metal nitrenoids. PMID:20617243

  13. Physical activity in patients with advanced-stage cancer: a systematic review of the literature.

    PubMed

    Albrecht, Tara A; Taylor, Ann Gill

    2012-06-01

    The importance of physical activity for chronic disease prevention and management has become generally well accepted. The number of research interventions and publications examining the benefits of physical activity for patients with cancer has been rising steadily. However, much of that research has focused on the impact of physical activity either prior to or early in the cancer diagnosis, treatment, and survivorship process. Research focusing on the effects of physical activity, specifically for patients with advanced-stage cancer and poorer prognostic outcomes, has been addressed only recently. The purpose of this article is to examine the state of the science for physical activity in the advanced-stage disease subset of the cancer population. Exercise in a variety of intensities and forms, including yoga, walking, biking, and swimming, has many health benefits for people, including those diagnosed with cancer. Research has shown that, for people with cancer (including advanced-stage cancer), exercise can decrease anxiety, stress, and depression while improving levels of pain, fatigue, shortness of breath, constipation, and insomnia. People diagnosed with cancer should discuss with their oncologist safe, easy ways they can incorporate exercise into their daily lives.

  14. Improving fundamental abilities of atomic force microscopy for investigating quantitative nanoscale physical properties of complex biological systems

    NASA Astrophysics Data System (ADS)

    Cartagena-Rivera, Alexander X.

    Measurements of local material properties of complex biological systems (e.g. live cells and viruses) in their respective physiological conditions are extremely important in the fields of biophysics, nanotechnology, material science, and nanomedicine. Yet, little is known about the structure-function-property relationship of live cells and viruses. In the case of live cells, the measurements of progressive variations in viscoelastic properties in vitro can provide insight to the mechanistic processes underpinning morphogenesis, mechano-transduction, motility, metastasis, and many more fundamental cellular processes. In the case of living viruses, the relationship between capsid structural framework and the role of the DNA molecule interaction within viruses influencing their stiffness, damping and electrostatic properties can shed light in virological processes like protein subunits assembly/dissassembly, maturation, and infection. The study of mechanics of live cells and viruses has been limited in part due to the lack of technology capable of acquiring high-resolution (nanoscale, subcellular) images of its heterogeneous material properties which vary widely depending on origin and physical interaction. The capabilities of the atomic force microscope (AFM) for measuring forces and topography with sub-nm precision have greatly contributed to research related to biophysics and biomechanics during the past two decades. AFM based biomechanical studies have the unique advantage of resolving/mapping spatially the local material properties over living cells and viruses. However, conventional AFM techniques such as force-volume and quasi-static force-distance curves are too low resolution and low speed to resolve interesting biophysical processes such as cytoskeletal dynamics for cells or assembly/dissasembly of viruses. To overcome this bottleneck, a novel atomic force microscopy mode is developed, that leads to sub-10-nm resolution and sub-15-minutes mapping of local

  15. Strategies for Advancing Women in Physics and other Sciences in an Undergraduate Hispanic Institution (abstract)

    NASA Astrophysics Data System (ADS)

    Ramos, Idalia

    2009-04-01

    For the past 15 years, University of Puerto Rico at Humacao (UPRH) has implemented various efforts to increase participation and promote advancement of women in physics and other sciences. The strategies used include mentoring, collaborating, forming women's organizations, and offering training workshops. The physics program at UPRH is the largest in Puerto Rico with approximately 95 undergraduates. Since 1995, female students in the program have increased from 17% to 32%. Efforts to integrate women in undergraduate research as early as possible in their studies show promising results, with the percentage of women in research increasing from 13% to 60% in the last 13 years. The Faculty in Training (FIT) program, begun in 2003, has supported talented women students interested in academic careers. The first FIT physics student will obtain her PhD in 2009. At the faculty level, UPRH received a first-round US National Science Foundation ADVANCE Institutional Transformation Award in 2001. The ADVANCE legacy at UPRH is evident at levels ranging from changes in individual behaviors to the adoption of institutional policies. A strong network of women in science and their supporters continues to advance this legacy.

  16. Atoms and Molecules. Physical Science in Action[TM]. Schlessinger Science Library. [Videotape].

    ERIC Educational Resources Information Center

    2000

    There are more than 20 million known substances in the universe, and they are all made of the same basic ingredients--atoms and molecules. In this fun and engaging program, kids will learn about the three main subatomic particles--protons, neutrons and electrons--as well as the forces that keep atoms and molecules together. They'll discover how…

  17. Atomic physics with hard X-rays from high brilliance synchrotron light sources

    SciTech Connect

    Southworth, S.; Gemmell, D.

    1996-08-01

    A century after the discovery of x rays, the experimental capability for studying atomic structure and dynamics with hard, bright synchrotron radiation is increasing remarkably. Tempting opportunities arise for experiments on many-body effects, aspects of fundamental photon-atom interaction processes, and relativistic and quantum-electrodynamic phenomena. Some of these possibilities are surveyed in general terms.

  18. Physical Construction of the Chemical Atom: Is It Convenient to Go All the Way Back?

    ERIC Educational Resources Information Center

    Izquierdo-Aymerich, Merce; Aduriz-Bravo, Agustin

    2009-01-01

    In this paper we present an analysis of chemistry texts (mainly textbooks) published during the first half of the 20th century. We show the evolution of the explanations therein in terms of atoms and of atomic structure, when scientists were interpreting phenomena as evidence of the discontinuous, corpuscular structure of matter. In this process…

  19. How Gender and Reformed Introductory Physics Impacts Student Success in Advanced Physics Courses and Continuation in the Physics Major

    ERIC Educational Resources Information Center

    Rodriguez, Idaykis; Potvin, Geoff; Kramer, Laird H.

    2016-01-01

    Active-learning approaches to teaching introductory physics have been found to improve student learning and affective gains on short-term outcomes [S. Freeman et al., "Proc. Natl. Acad. Sci. U.S.A. 111," 8410 (2014)]; however, whether or not the benefits of active learning impact women to the same degree as men has been a point of…

  20. Emulating solid-state physics with a hybrid system of ultracold ions and atoms.

    PubMed

    Bissbort, U; Cocks, D; Negretti, A; Idziaszek, Z; Calarco, T; Schmidt-Kaler, F; Hofstetter, W; Gerritsma, R

    2013-08-23

    We propose and theoretically investigate a hybrid system composed of a crystal of trapped ions coupled to a cloud of ultracold fermions. The ions form a periodic lattice and induce a band structure in the atoms. This system combines the advantages of high fidelity operations and detection offered by trapped ion systems with ultracold atomic systems. It also features close analogies to natural solid-state systems, as the atomic degrees of freedom couple to phonons of the ion lattice, thereby emulating a solid-state system. Starting from the microscopic many-body Hamiltonian, we derive the low energy Hamiltonian, including the atomic band structure, and give an expression for the atom-phonon coupling. We discuss possible experimental implementations such as a Peierls-like transition into a period-doubled dimerized state.

  1. Advancing Efficient All-Electron Electronic Structure Methods Based on Numeric Atom-Centered Orbitals for Energy Related Materials

    NASA Astrophysics Data System (ADS)

    Blum, Volker

    This talk describes recent advances of a general, efficient, accurate all-electron electronic theory approach based on numeric atom-centered orbitals; emphasis is placed on developments related to materials for energy conversion and their discovery. For total energies and electron band structures, we show that the overall accuracy is on par with the best benchmark quality codes for materials, but scalable to large system sizes (1,000s of atoms) and amenable to both periodic and non-periodic simulations. A recent localized resolution-of-identity approach for the Coulomb operator enables O (N) hybrid functional based descriptions of the electronic structure of non-periodic and periodic systems, shown for supercell sizes up to 1,000 atoms; the same approach yields accurate results for many-body perturbation theory as well. For molecular systems, we also show how many-body perturbation theory for charged and neutral quasiparticle excitation energies can be efficiently yet accurately applied using basis sets of computationally manageable size. Finally, the talk highlights applications to the electronic structure of hybrid organic-inorganic perovskite materials, as well as to graphene-based substrates for possible future transition metal compound based electrocatalyst materials. All methods described here are part of the FHI-aims code. VB gratefully acknowledges contributions by numerous collaborators at Duke University, Fritz Haber Institute Berlin, TU Munich, USTC Hefei, Aalto University, and many others around the globe.

  2. Reactor Physics and Criticality Benchmark Evaluations for Advanced Nuclear Fuel - Final Technical Report

    SciTech Connect

    William Anderson; James Tulenko; Bradley Rearden; Gary Harms

    2008-09-11

    The nuclear industry interest in advanced fuel and reactor design often drives towards fuel with uranium enrichments greater than 5 wt% 235U. Unfortunately, little data exists, in the form of reactor physics and criticality benchmarks, for uranium enrichments ranging between 5 and 10 wt% 235U. The primary purpose of this project is to provide benchmarks for fuel similar to what may be required for advanced light water reactors (LWRs). These experiments will ultimately provide additional information for application to the criticality-safety bases for commercial fuel facilities handling greater than 5 wt% 235U fuel.

  3. Engineering development of advanced physical fine coal cleaning for premium fuel applications

    SciTech Connect

    Smit, F.J.; Jha, M.C.; Phillips, D.I.; Yoon, R.H.

    1997-04-25

    The goal of this project is engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. Its scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by design and construction of a 2 t/h process development unit (PDU). Large lots of clean coal are to be produced in the PDU from three project coals. Investigation of the near-term applicability of the two advanced fine coal cleaning processes in an existing coal preparation plant is another goal of the project and is the subject of this report.

  4. Innovative experimental particle physics through technological advances: Past, present and future

    SciTech Connect

    Cheung, Harry W.K.; /Fermilab

    2005-01-01

    This mini-course gives an introduction to the techniques used in experimental particle physics with an emphasis on the impact of technological advances. The basic detector types and particle accelerator facilities will be briefly covered with examples of their use and with comparisons. The mini-course ends with what can be expected in the near future from current technology advances. The mini-course is intended for graduate students and post-docs and as an introduction to experimental techniques for theorists.

  5. Advancing Navigation, Timing, and Science with the Deep Space Atomic Clock

    NASA Technical Reports Server (NTRS)

    Ely, Todd A.; Seubert, Jill; Bell, Julia

    2014-01-01

    NASA's Deep Space Atomic Clock mission is developing a small, highly stable mercury ion atomic clock with an Allan deviation of at most 1e-14 at one day, and with current estimates near 3e-15. This stability enables one-way radiometric tracking data with accuracy equivalent to and, in certain conditions, better than current two-way deep space tracking data; allowing a shift to a more efficient and flexible one-way deep space navigation architecture. DSAC-enabled one-way tracking will benefit navigation and radio science by increasing the quantity and quality of tracking data. Additionally, DSAC would be a key component to fully-autonomous onboard radio navigation useful for time-sensitive situations. Potential deep space applications of DSAC are presented, including orbit determination of a Mars orbiter and gravity science on a Europa flyby mission.

  6. Atomic-Scale Investigation of Latent Fission Tracks in Fluorapatite: Physical Characteristics and Annealing Behavior.

    NASA Astrophysics Data System (ADS)

    Paul, Tracy Anne

    1993-01-01

    A JEOL JEM-2000FX analytical transmission electron microscope, equipped with a cold stage and anticontamination device, has been used to study the physical characteristics and annealing behavior of artificially induced fission tracks in fluorapatite. Near the atomic level, unetched fission tracks are not continuous, but are comprised of segments of extended damage that are separated by gaps of undamaged microstructure. From dark-field transmission electron microscopy (TEM) images, it appears that the crystalline damage around tracks, although intensive, is not extensive. As such, the defect density may be represented by a Gaussian-type distribution function. The disordered nature of the track core and defect distribution geometry supports the Ion-Explosion Theory that has been proposed for track formation. TEM analysis reveals that track width is crystallographically controlled. Parallel to the c-axis, tracks display widths of 5 to 13 nm and hexagonal faceting on the (0001) plane. Tracks perpendicular to the c-axis display widths of 3 to 9 nm and prismatic faceting on the (1000) plane. The track cross-section facets mimic etch-pit morphologies and provide a relative measure of the crystal's surface free energy. A consequence of differential bond strengths and elastic properties in the fluorapatite structure, track-width anisotropy resolves etching- and annealing-rate anisotropy that has been reported for fission tracks in fluorapatite. TEM observation of the behavior of fission tracks in response to electron beam exposure (i.e., radiolytic annealing), and temperature increase (i.e., thermal annealing), yields a physical and a kinetic description of the annealing process. Annealing commences with bulging at the track's tapered ends, followed by detachment of a single sphere. This process is replicated until a critical track radius is encountered at which the track geometry approaches an ideal right cylinder. A sinusoidal boundary develops at the track

  7. Single atom electrochemical and atomic analytics

    NASA Astrophysics Data System (ADS)

    Vasudevan, Rama

    In the past decade, advances in electron and scanning-probe based microscopies have led to a wealth of imaging and spectroscopic data with atomic resolution, yielding substantial insight into local physics and chemistry in a diverse range of systems such as oxide catalysts, multiferroics, manganites, and 2D materials. However, typical analysis of atomically resolved images is limited, despite the fact that image intensities and distortions of the atoms from their idealized positions contain unique information on the physical and chemical properties inherent to the system. Here, we present approaches to data mine atomically resolved images in oxides, specifically in the hole-doped manganite La5/8Ca3/8MnO3, on epitaxial films studied by in-situ scanning tunnelling microscopy (STM). Through application of bias to the STM tip, atomic-scale electrochemistry is demonstrated on the manganite surface. STM images are then further analyzed through a suite of algorithms including 2D autocorrelations, sliding window Fourier transforms, and others, and can be combined with basic thermodynamic modelling to reveal relevant physical and chemical descriptors including segregation energies, existence and strength of atomic-scale diffusion barriers, surface energies and sub-surface chemical species identification. These approaches promise to provide tremendous insights from atomically resolved functional imaging, can provide relevant thermodynamic parameters, and auger well for use with first-principles calculations to yield quantitative atomic-level chemical identification and structure-property relations. This research was sponsored by the Division of Materials Sciences and Engineering, BES, DOE. Research was conducted at the Center for Nanophase Materials Sciences, which also provided support and is a DOE Office of Science User Facility.

  8. High Performance Computing Modeling Advances Accelerator Science for High-Energy Physics

    SciTech Connect

    Amundson, James; Macridin, Alexandru; Spentzouris, Panagiotis

    2014-07-28

    The development and optimization of particle accelerators are essential for advancing our understanding of the properties of matter, energy, space, and time. Particle accelerators are complex devices whose behavior involves many physical effects on multiple scales. Therefore, advanced computational tools utilizing high-performance computing are essential for accurately modeling them. In the past decade, the US Department of Energy's SciDAC program has produced accelerator-modeling tools that have been employed to tackle some of the most difficult accelerator science problems. The authors discuss the Synergia framework and its applications to high-intensity particle accelerator physics. Synergia is an accelerator simulation package capable of handling the entire spectrum of beam dynamics simulations. Our authors present Synergia's design principles and its performance on HPC platforms.

  9. High Performance Computing Modeling Advances Accelerator Science for High-Energy Physics

    DOE PAGES

    Amundson, James; Macridin, Alexandru; Spentzouris, Panagiotis

    2014-07-28

    The development and optimization of particle accelerators are essential for advancing our understanding of the properties of matter, energy, space, and time. Particle accelerators are complex devices whose behavior involves many physical effects on multiple scales. Therefore, advanced computational tools utilizing high-performance computing are essential for accurately modeling them. In the past decade, the US Department of Energy's SciDAC program has produced accelerator-modeling tools that have been employed to tackle some of the most difficult accelerator science problems. The authors discuss the Synergia framework and its applications to high-intensity particle accelerator physics. Synergia is an accelerator simulation package capable ofmore » handling the entire spectrum of beam dynamics simulations. Our authors present Synergia's design principles and its performance on HPC platforms.« less

  10. DAWN (Design Assistant Workstation) for advanced physical-chemical life support systems

    NASA Technical Reports Server (NTRS)

    Rudokas, Mary R.; Cantwell, Elizabeth R.; Robinson, Peter I.; Shenk, Timothy W.

    1989-01-01

    This paper reports the results of a project supported by the National Aeronautics and Space Administration, Office of Aeronautics and Space Technology (NASA-OAST) under the Advanced Life Support Development Program. It is an initial attempt to integrate artificial intelligence techniques (via expert systems) with conventional quantitative modeling tools for advanced physical-chemical life support systems. The addition of artificial intelligence techniques will assist the designer in the definition and simulation of loosely/well-defined life support processes/problems as well as assist in the capture of design knowledge, both quantitative and qualitative. Expert system and conventional modeling tools are integrated to provide a design workstation that assists the engineer/scientist in creating, evaluating, documenting and optimizing physical-chemical life support systems for short-term and extended duration missions.

  11. Atomic physics of strongly correlated systems. Progress report, 1 August 1980-31 July 1981

    SciTech Connect

    Lin, C.D.

    1981-03-01

    Studies of electron correlations of doubly-excited electrons in hyperspherical coordinates, and differential and total cross sections for charge transfer and ionization in fast ion-atom collisions are reported. (GHT)

  12. A Learning Pathway in High-School Level Quantum Atomic Physics.

    ERIC Educational Resources Information Center

    Petri, Juergen; Niedderer, Hans

    1998-01-01

    Describes one student's learning pathway as a sequence of several metastable conceptions of the atom starting from a planetary model. Displays the final cognitive element as an association of three parallel conceptions. Contains 26 references. (DDR)

  13. Nonlocal thermodynamic equilibrium self-consistent average-atom model for plasma physics.

    PubMed

    Faussurier, G; Blancard, C; Berthier, E

    2001-02-01

    A time-dependent collisional-radiative average-atom model is presented to study statistical properties of highly charged ion plasmas in off-equilibrium conditions. The time evolution of electron populations and the electron covariance matrix is obtained as approximate solutions of a master equation. Atomic structure is described either with a screened-hydrogenic model including l splitting, or by calculating one-electron states in a self-consistent average-atom potential. Collisional and radiative excitation/deexcitation and ionization/recombination rates, as well as autoionization and dielectronic recombination rates, are formulated within the average-configuration framework. Local thermodynamic equilibrium is obtained as a specific steady-state solution. The influence of atomic structure and the role of autoionization and dielectronic recombination processes are studied by calculating steady-state average ionization and ionization variance of hot plasmas with or without radiation field.

  14. FROM THE HISTORY OF PHYSICS: L D Landau in the Soviet Atomic Project: a documentary study

    NASA Astrophysics Data System (ADS)

    Kiselev, G. V.

    2008-09-01

    The article presents information about the participation of Academician L D Landau in the Soviet Atomic Project and is based on a study of archive documents of the First Main Directorate. Their analysis points to L D Landau's important contribution to the development of the theory of heterogeneous nuclear reactors and to the computational justification of the first designs of atomic and hydrogen bombs. Many of the quoted documents have never been published before.

  15. Electron collisions with atoms, ions, molecules, and surfaces: Fundamental science empowering advances in technology

    NASA Astrophysics Data System (ADS)

    Bartschat, Klaus; Kushner, Mark J.

    2016-06-01

    Electron collisions with atoms, ions, molecules, and surfaces are critically important to the understanding and modeling of low-temperature plasmas (LTPs), and so in the development of technologies based on LTPs. Recent progress in obtaining experimental benchmark data and the development of highly sophisticated computational methods is highlighted. With the cesium-based diode-pumped alkali laser and remote plasma etching of Si3N4 as examples, we demonstrate how accurate and comprehensive datasets for electron collisions enable complex modeling of plasma-using technologies that empower our high-technology-based society.

  16. Electron collisions with atoms, ions, molecules, and surfaces: Fundamental science empowering advances in technology.

    PubMed

    Bartschat, Klaus; Kushner, Mark J

    2016-06-28

    Electron collisions with atoms, ions, molecules, and surfaces are critically important to the understanding and modeling of low-temperature plasmas (LTPs), and so in the development of technologies based on LTPs. Recent progress in obtaining experimental benchmark data and the development of highly sophisticated computational methods is highlighted. With the cesium-based diode-pumped alkali laser and remote plasma etching of Si3N4 as examples, we demonstrate how accurate and comprehensive datasets for electron collisions enable complex modeling of plasma-using technologies that empower our high-technology-based society.

  17. Electron collisions with atoms, ions, molecules, and surfaces: Fundamental science empowering advances in technology

    PubMed Central

    Bartschat, Klaus; Kushner, Mark J.

    2016-01-01

    Electron collisions with atoms, ions, molecules, and surfaces are critically important to the understanding and modeling of low-temperature plasmas (LTPs), and so in the development of technologies based on LTPs. Recent progress in obtaining experimental benchmark data and the development of highly sophisticated computational methods is highlighted. With the cesium-based diode-pumped alkali laser and remote plasma etching of Si3N4 as examples, we demonstrate how accurate and comprehensive datasets for electron collisions enable complex modeling of plasma-using technologies that empower our high-technology–based society. PMID:27317740

  18. Synthesis and Functionalization of Atomic Layer Boron Nitride Nanosheets for Advanced Material Applications

    DTIC Science & Technology

    2014-06-05

    Solid State Phase…………………………………………………… 9 1.6 Energy Bang Gap Modification in BNNSs………………………………………… 10 1.7 Applications of BNNSs...density functional theory calculations [52-56]. However, BNNTs present a low sensitivity to the various gaseous molecules, while few atomic layer...obtained around =4.210 2 m. It is believed that spatially non-uniform the membrane would not possibly cause such big difference above. Large

  19. SOFTWARE REVIEW: The Advanced Physics Virtual Laboratory Series: CD-ROM Thermodynamics and Molecular Physics

    NASA Astrophysics Data System (ADS)

    Dobson, Ken

    1998-09-01

    The program installed easily although the inexperienced might be as terrified as I was by the statements threatening to delete various files it had found on my machine. However, I ignored these and all went well. The user is faced with a menu of 14 simulations covering molecular topics such as the Kinetic Model of an Ideal Gas, Diffusion (through a variable diameter aperture) and a Semi-permeable Membrane, the Maxwell Distribution and Brownian Motion. Thermodynamics is covered by simulations of ideal-gas behaviour at constant pressure, volume and temperature. This is extended to deal with adiabatic changes, the work done by and on a gas, specific heats, work cycles, and to the behaviour of real gases in evaporation and condensation. Finally there are short video-clips of actual experiments showing gas and vapour behaviour. Each simulation is displayed in a `picture window' which gives a qualitative display of how molecules are moving in a container, or how a parameter changes as conditions are varied, as appropriate. Attached (somewhat loosely as it turned out) to these are relevant graphs showing how the important variables such as temperature, volume and pressure change as conditions are changed. The simulations are dynamic and set off by clicking on a RUN button. The simulation can be stopped at any stage and reset to change parameters. It is easy to change the conditions of the simulation by moving sliders along a scale. I particularly liked the simulations of molecular behaviour and the isotherms of a real gas - an ideal case for animation. Each simulation has a short spoken commentary which you can switch in, a brief drop-down text describing the simulation, and a single question. This is where, I felt, things started to go wrong. The simulation displays are informative and give a good visual impression of a part of physics that students find abstract and difficult. But the supporting commentary and text are much too thin for, say, `supported self

  20. Physical properties of FePt nanocomposite doped with Ag atoms: First-principles study

    NASA Astrophysics Data System (ADS)

    Jia, Yong-Fei; Shu, Xiao-Lin; Xie, Yong; Chen, Zi-Yu

    2014-07-01

    L10 FePt nanocomposite with high magnetocrystalline anisotropy energy has been extensively investigated in the fields of ultra-high density magnetic recording media. However, the order—disorder transition temperature of the nanocomposite is higher than 600 °C, which is a disadvantage for the use of the material due to the sustained growth of FePt grain under the temperature. To address the problem, addition of Ag atoms has been proposed, but the magnetic properties of the doped system are still unclear so far. Here in this paper, we use first-principles method to study the lattice parameters, formation energy, electronic structure, atomic magnetic moment and order—disorder transition temperature of L10 FePt with Ag atom doping. The results show that the formation energy of a Ag atom substituting for a Pt site is 1.309 eV, which is lower than that of substituting for an Fe site 1.346 eV. The formation energy of substituting for the two nearest Pt sites is 2.560 eV lower than that of substituting for the further sites 2.621 eV, which indicates that Ag dopants tend to segregate L10 FePt. The special quasirandom structures (SQSs) for the pure FePt and the FePt doped with two Ag atoms at the stable Pt sites show that the order—disorder transition temperatures are 1377 °C and 600 °C, respectively, suggesting that the transition temperature can be reduced with Ag atom, and therefore the FePt grain growth is suppressed. The saturation magnetizations of the pure FePt and the two Ag atoms doped FePt are 1083 emu/cc and 1062 emu/cc, respectively, indicating that the magnetic property of the doped system is almost unchanged.

  1. Atomic layer deposition-Sequential self-limiting surface reactions for advanced catalyst "bottom-up" synthesis

    NASA Astrophysics Data System (ADS)

    Lu, Junling; Elam, Jeffrey W.; Stair, Peter C.

    2016-06-01

    Catalyst synthesis with precise control over the structure of catalytic active sites at the atomic level is of essential importance for the scientific understanding of reaction mechanisms and for rational design of advanced catalysts with high performance. Such precise control is achievable using atomic layer deposition (ALD). ALD is similar to chemical vapor deposition (CVD), except that the deposition is split into a sequence of two self-limiting surface reactions between gaseous precursor molecules and a substrate. The unique self-limiting feature of ALD allows conformal deposition of catalytic materials on a high surface area catalyst support at the atomic level. The deposited catalytic materials can be precisely constructed on the support by varying the number and type of ALD cycles. As an alternative to the wet-chemistry based conventional methods, ALD provides a cycle-by-cycle "bottom-up" approach for nanostructuring supported catalysts with near atomic precision. In this review, we summarize recent attempts to synthesize supported catalysts with ALD. Nucleation and growth of metals by ALD on oxides and carbon materials for precise synthesis of supported monometallic catalyst are reviewed. The capability of achieving precise control over the particle size of monometallic nanoparticles by ALD is emphasized. The resulting metal catalysts with high dispersions and uniformity often show comparable or remarkably higher activity than those prepared by conventional methods. For supported bimetallic catalyst synthesis, we summarize the strategies for controlling the deposition of the secondary metal selectively on the primary metal nanoparticle but not on the support to exclude monometallic formation. As a review of the surface chemistry and growth behavior of metal ALD on metal surfaces, we demonstrate the ways to precisely tune size, composition and structure of bimetallic metal nanoparticles. The cycle-by-cycle "bottom up" construction of bimetallic (or multiple

  2. Nuclear physics with advanced brilliant gamma beams at ELI-NP

    NASA Astrophysics Data System (ADS)

    Ur, Călin A.; Filipescu, Dan; Gheorghe, Ioana; Iancu, Violeta; Suliman, Gabriel; Teşileanu, Ovidiu

    2016-01-01

    The Extreme Light Infrastructure - Nuclear Physics facility is dedicated to nuclear physics studies with the use of extreme electromagnetic radiation. One of the main research system to be installed and operated in the facility is an outstanding high brilliance gamma beam system. The Gamma Beam System of ELI-NP will produce intense, quasi-monochromatic gamma beams via inverse Compton scattering of short laser pulses on relativistic electron beam pulses. The gamma beams available at ELI-NP will allow for the performance of photo-nuclear reactions aiming to reveal the intimate structure of the atomic nucleus. Nuclear Resonance Fluorescence, photo-fission, photo-disintegration reactions above the particle threshold will be used to study the dipole response of nuclei, the structure of the Pygmy resonances, nuclear processes relevant for astrophysics, production and study of exotic neutron-rich nuclei.

  3. Technical Basis for Physical Fidelity of NRC Control Room Training Simulators for Advanced Reactors

    SciTech Connect

    Minsk, Brian S.; Branch, Kristi M.; Bates, Edward K.; Mitchell, Mark R.; Gore, Bryan F.; Faris, Drury K.

    2009-10-09

    The objective of this study is to determine how simulator physical fidelity influences the effectiveness of training the regulatory personnel responsible for examination and oversight of operating personnel and inspection of technical systems at nuclear power reactors. It seeks to contribute to the U.S. Nuclear Regulatory Commission’s (NRC’s) understanding of the physical fidelity requirements of training simulators. The goal of the study is to provide an analytic framework, data, and analyses that inform NRC decisions about the physical fidelity requirements of the simulators it will need to train its staff for assignment at advanced reactors. These staff are expected to come from increasingly diverse educational and experiential backgrounds.

  4. Constraints on a long-range spin-independent interaction from precision atomic physics

    SciTech Connect

    Karshenboim, S. G.

    2010-10-01

    Constraints on a spin-independent interaction by the exchange of a neutral light boson are derived from precision data on the electron anomalous magnetic moment and from atomic spectroscopy of hydrogen and deuterium atoms. The mass range from 1 eV/c{sup 2} to 1 MeV/c{sup 2} is studied, and the effective coupling constant {alpha}{sup '} is allowed below the level of 10{sup -11}-10{sup -13} depending on the value of the boson mass. The mass range corresponds to the Yukawa radius from 0.0002 nm to 20 nm, which covers the distances far above and far below the Bohr radius of the hydrogen atom.

  5. Simulation of nucleation and growth of atomic layer deposition phosphorus for doping of advanced FinFETs

    SciTech Connect

    Seidel, Thomas E.; Goldberg, Alexander; Halls, Mat D.; Current, Michael I.

    2016-01-15

    Simulations for the nucleation and growth of phosphorus films were carried out using density functional theory. The surface was represented by a Si{sub 9}H{sub 12} truncated cluster surface model with 2 × 1-reconstructured (100) Si-OH terminations for the initial reaction sites. Chemistries included phosphorous halides (PF{sub 3}, PCl{sub 3}, and PBr{sub 3}) and disilane (Si{sub 2}H{sub 6}). Atomic layer deposition (ALD) reaction sequences were illustrated with three-dimensional molecular models using sequential PF{sub 3} and Si{sub 2}H{sub 6} reactions and featuring SiFH{sub 3} as a byproduct. Exothermic reaction pathways were developed for both nucleation and growth for a Si-OH surface. Energetically favorable reactions for the deposition of four phosphorus atoms including lateral P–P bonding were simulated. This paper suggests energetically favorable thermodynamic reactions for the growth of elemental phosphorus on (100) silicon. Phosphorus layers made by ALD are an option for doping advanced fin field-effect transistors (FinFETs). Phosphorus may be thermally diffused into the silicon or recoil knocked in; simulations of the recoil profile of phosphorus into a FinFET surface are illustrated.

  6. Advancements in Ti Alloy Powder Production by Close-Coupled Gas Atomization

    SciTech Connect

    Heidloff, Andy; Rieken, Joel; Anderson, Iver; Byrd, David

    2011-04-01

    As the technology for titanium metal injection molding (Ti-MIM) becomes more readily available, efficient Ti alloy fine powder production methods are required. An update on a novel close-coupled gas atomization system has been given. Unique features of the melting apparatus are shown to have measurable effects on the efficiency and ability to fully melt within the induction skull melting system (ISM). The means to initiate the melt flow were also found to be dependent on melt apparatus. Starting oxygen contents of atomization feedstock are suggested based on oxygen pick up during the atomization and MIM processes and compared to a new ASTM specification. Forming of titanium by metal injection molding (Ti-MIM) has been extensively studied with regards to binders, particle shape, and size distribution and suitable de-binding methods have been discovered. As a result, the visibility of Ti-MIM has steadily increased as reviews of technology, acceptability, and availability have been released. In addition, new ASTM specification ASTM F2885-11 for Ti-MIM for biomedical implants was released in early 2011. As the general acceptance of Ti-MIM as a viable fabrication route increases, demand for economical production of high quality Ti alloy powder for the preparation of Ti-MIM feedstock correspondingly increases. The production of spherical powders from the liquid state has required extensive pre-processing into different shapes thereby increasing costs. This has prompted examination of Ti-MIM with non-spherical particle shape. These particles are produced by the hydride/de-hydride process and are equi-axed but fragmented and angular which is less than ideal. Current prices for MIM quality titanium powder range from $40-$220/kg. While it is ideal for the MIM process to utilize spherical powders within the size range of 0.5-20 {mu}m, titanium's high affinity for oxygen to date has prohibited the use of this powder size range. In order to meet oxygen requirements the top size

  7. Enhancing Laos Students' Understanding of Nature of Science in Physics Learning about Atom for Peace

    ERIC Educational Resources Information Center

    Sengdala, Phoxay; Yuenyong, Chokchai

    2014-01-01

    This paper aimed to study of Grade 12 students' understanding of nature of science in learning about atom for peace through science technology and society (STS) approach. Participants were 51 Grade 12 who study in Thongphong high school Vientiane Capital City Lao PDR, 1st semester of 2012 academic year. This research regarded interpretive…

  8. Atomic physics with highly charged ions. Progress report, FY 1989--91

    SciTech Connect

    Richard, P.

    1991-08-01

    This report discusses: One electron outer shell processes in fast ion-atom collisions; role of electron-electron interaction in two-electron processes; multi-electron processes at low energy; multi-electron processes at high energy; inner shell processes; molecular fragmentation studies; theory; and, JRM laboratory operations.

  9. INSTRUMENTS AND METHODS OF INVESTIGATION: Physical mechanisms underlying the selective removal of atoms

    NASA Astrophysics Data System (ADS)

    Gurovich, Boris A.; Prikhod'ko, Kirill E.

    2009-02-01

    This paper reviews the current understanding of the selective removal of atoms (SRA), a technique that uses ion irradiation to controllably change the chemical composition and properties of polyatomic materials. The main effects involved and the possible mechanisms that govern the process are discussed. It is shown that SRA holds great promise for manufacturing functional nanoelements.

  10. Short animation movies as advance organizers in physics teaching: a preliminary study

    NASA Astrophysics Data System (ADS)

    Koscianski, André; João Ribeiro, Rafael; Carvalho Rutz da Silva, Sani

    2012-11-01

    Background : Advance organizers are instructional materials that help students use previous knowledge to make links with new information. Short animation movies are a possible format and are well suited for physics, as they can portray dynamic phenomena and represent abstract concepts. Purpose : The study aimed to determine guidelines for the construction of an instructional short animation movie, with the role of an advance organizer. A film was created in order to evaluate the effectiveness of the approach, making part of a physics lesson and concerning the subject 'moment of a force'. Sample : The study took place in a Brazilian school in the city of Arapoti, in the south region of the country. Thirty-eight students participated, having an average age of 16 and following the third year of high school. Design and methods : Criteria drawn from a literature review directed the construction of the movie and the lesson. Data were collected using pre- and post-tests; registers of oral comments were also done during the class. The post-test included open-ended questions, allowing students to write remarks concerning the lesson and the animation. Conclusions : The article describes steps and guidelines to orient the process of designing an animation movie with the role of advance organizer. Data indicated that the movie facilitated the construction of links between pre-existent knowledge and the new information presented in the lesson. The proposed methodology can be considered a valid framework to derive similar approaches.

  11. Reducing anxiety and enhancing physical performance by using an advanced version of EMDR: a pilot study

    PubMed Central

    Rathschlag, Marco; Memmert, Daniel

    2014-01-01

    Background The main aim of this pilot study was to investigate an advanced version of eye movement desensitization and reprocessing (EMDR) for reducing anxiety. Methods Fifty participants were asked at two times of measurement (T1 and T2 with a rest of 4 weeks) to generate anxiety via the recall of autobiographical memories according to their anxiety. Furthermore, the participants were randomly assigned to an experimental group and a control group, and the experimental group received an intervention of 1–2 h with the advanced version of EMDR in order to their anxiety 2 weeks after T1. At T1 as well as T2, we measured the intensity of participants' anxiety with a Likert scale (LS) and collected participants' state (temporary) and trait (chronic) anxiety with the State-Trait Anxiety Inventory (STAI). In addition, we measured participants' physical performance in a test for the finger musculature under the induction of their anxiety. Results The results showed that participant's ratings of their perceived intensity of anxiety (measured by a 9-point LS) and the state and trait anxiety decreased significantly in the experimental group but not in the control group from T1 to T2. Moreover, the physical performance under the induction of participants' anxiety increased significantly in the experimental group from T1 to T2 and there were no significant changes in the control group. Conclusions The study could show that the advanced version of EMDR is an appropriate method to reduce anxiety. PMID:24944864

  12. Advances in research on structural characterisation of agricultural products using atomic force microscopy.

    PubMed

    Liu, Dongli; Cheng, Fang

    2011-03-30

    Atomic force microscopy (AFM) has many unique features compared with other conventional microscopies, such as high magnification with high resolution, minimal sample preparation, acquiring 2D and 3D images at the same time, observing ongoing processes directly, the possibility of manipulating macromolecules, etc. As a nanotechnology tool, AFM has been used to investigate the nanostructure of materials in many fields. This mini-review focuses mainly on its latest application to characterise the macromolecular nanostructure and surface topography of agricultural products. First the fundamentals of AFM are briefly explained. Then the macromolecular nanostructure information on agricultural products from AFM images is introduced by exploring the structure-function relationship in three aspects: agricultural product processing, agricultural product ripening and storage, and genetic and environmental factors. The surface topography characterisation of agricultural products using AFM is also discussed. The results reveal that AFM could be a powerful nanotechnology tool to acquire a deeper understanding of the mechanisms of structure and quality variations of agricultural products, which could be instructive in improving processing and storage technologies, and AFM is also helpful to reveal the essential nature of a product at nanoscale.

  13. Optimized Model Surfaces for Advanced Atomic Force Microscopy Studies of Surface Nanobubbles.

    PubMed

    Song, Bo; Zhou, Yi; Schönherr, Holger

    2016-11-01

    The formation of self-assembled monolayers (SAMs) of binary mixtures of 16-mercaptohexadecanoic acid (MHDA) and 1-octadecanethiol (ODT) on ultraflat template-stripped gold (TSG) surfaces was systematically investigated to clarify the assembly behavior, composition, and degree of possible phase segregation in light of atomic force microscopy (AFM) studies of surface nanobubbles on these substrates. The data for SAMs on TSG were compared to those obtained by adsorption on rough evaporated gold, as reported in a previous study. Quartz crystal microbalance and surface plasmon resonance data acquired in situ on TSG indicate that similar to SAM formation on conventional evaporated gold substrates ODT and MHDA form monolayers and bilayers, respectively. The second layer on MHDA, whose formation is attributed to hydrogen bonding, can be easily removed by adequate rinsing with water. The favorable agreement of the grazing incidence reflection Fourier transform infrared (GIR FTIR) spectroscopy and contact angle data analyzed with the Israelachvili-Gee model suggests that the binary SAMs do not segregate laterally. This conclusion is fully validated by high-resolution friction force AFM observations down to a length scale of 8-10 nm, which is much smaller than the typical observed surface nanobubble radii. Finally, correspondingly functionalized TSG substrates are shown to be valuable supports for studying surface nanobubbles by AFM in water and for addressing the relation between surface functionality and nanobubble formation and properties.

  14. Integration of Advanced Probabilistic Analysis Techniques with Multi-Physics Models

    SciTech Connect

    Cetiner, Mustafa Sacit; none,; Flanagan, George F.; Poore III, Willis P.; Muhlheim, Michael David

    2014-07-30

    An integrated simulation platform that couples probabilistic analysis-based tools with model-based simulation tools can provide valuable insights for reactive and proactive responses to plant operating conditions. The objective of this work is to demonstrate the benefits of a partial implementation of the Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Detailed Framework Specification through the coupling of advanced PRA capabilities and accurate multi-physics plant models. Coupling a probabilistic model with a multi-physics model will aid in design, operations, and safety by providing a more accurate understanding of plant behavior. This represents the first attempt at actually integrating these two types of analyses for a control system used for operations, on a faster than real-time basis. This report documents the development of the basic communication capability to exchange data with the probabilistic model using Reliability Workbench (RWB) and the multi-physics model using Dymola. The communication pathways from injecting a fault (i.e., failing a component) to the probabilistic and multi-physics models were successfully completed. This first version was tested with prototypic models represented in both RWB and Modelica. First, a simple event tree/fault tree (ET/FT) model was created to develop the software code to implement the communication capabilities between the dynamic-link library (dll) and RWB. A program, written in C#, successfully communicates faults to the probabilistic model through the dll. A systems model of the Advanced Liquid-Metal Reactor–Power Reactor Inherently Safe Module (ALMR-PRISM) design developed under another DOE project was upgraded using Dymola to include proper interfaces to allow data exchange with the control application (ConApp). A program, written in C+, successfully communicates faults to the multi-physics model. The results of the example simulation were successfully plotted.

  15. Recent Advances in Free-Living Physical Activity Monitoring: A Review

    PubMed Central

    Andre, David; Wolf, Donna L.

    2007-01-01

    It has become clear recently that the epidemic of type 2 diabetes sweeping the globe is associated with decreased levels of physical activity and an increase in obesity. Incorporating appropriate and sufficient physical activity into one's life is an essential component of achieving and maintaining a healthy weight and overall health, especially for those with type II diabetes mellitus. Regular physical activity can have a positive impact by lowering blood glucose, helping the body to be more efficient at using insulin. There are other substantial benefits for patients with diabetes, including prevention of cardiovascular disease, hyperlipidemia, hypertension, and obesity. Several complications of utilizing a self-care treatment methodology involving exercise include (1) patients may not know how much activity that they engage in and (2) health-care providers do not have objective measurements of how much activity their patients perform. However, several technological advances have brought a variety of activity monitoring devices to the market that can address these concerns. Ranging from simple pedometers to multisensor devices, the different technologies offer varying levels of accuracy, comfort, and reliability. The key notion is that by providing feedback to the patient, motivation can be increased and targets can be set and aimed toward. Although these devices are not specific to the treatment of diabetes, the importance of physical activity in treating the disease makes an understanding of these devices important. This article reviews these physical activity monitors and describes the advantages and disadvantages of each. PMID:19885145

  16. Advances of Yemeni women in physics: Climbing toward a better status

    NASA Astrophysics Data System (ADS)

    Fakhraddin, S.; Alsowidi, N. A.

    2013-03-01

    In the three years since the last IUPAP Women in Physics Conference in 2008, the overall status of women in physics in Yemen has improved. The enrollment of women in the Department of Physics at Sana'a University has increased at both the undergraduate and graduate levels. At the graduate level, female enrollment has been equal to (50%) or greater than (57%) male enrollment in recent years. In addition, four of the leading state universities already have female faculty members with a PhD in physics who hold the title of assistant professor or better. These women in academia have made remarkable progress by publishing their work in distinctive journals as well as by winning national and regional scientific awards. We can be rather satisfied with the overall advances of Yemeni women in physics, as well, at every step up the academic ladder, but we simultaneously acknowledge their significant underrepresentation in the highest scientific positions as well as in decision-making positions at the faculty or administrative level of universities.

  17. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    SciTech Connect

    Not Available

    1992-01-01

    A study conducted by Pittsburgh Energy Technology Center of sulfur emissions from about 1,300 United States coal-fired utility boilers indicated that half of the emissions were the result of burning coals having greater than 1.2 pounds of SO[sub 2] per million BTU. This was mainly attributed to the high pyritic sulfur content of the boiler fuel. A significant reduction in SO[sub 2] emissions could be accomplished by removing the pyrite from the coals by advanced physical fine coal cleaning. An engineering development project was prepared to build upon the basic research effort conducted under a solicitation for research into Fine Coal Surface Control. The engineering development project is intended to use general plant design knowledge and conceptualize a plant to utilize advanced froth flotation technology to process coal and produce a product having maximum practical pyritic sulfur reduction consistent with maximum practical BTU recovery.

  18. Advanced atomic force microscopy techniques for characterizing the properties of cellulosic nanomaterials

    NASA Astrophysics Data System (ADS)

    Wagner, Ryan Bradley

    The measurement of nanomechanical properties is of great interest to science and industry. Key to progress in this area is the development of new techniques and analysis methods to identify, measure, and quantify these properties. In this dissertation, new data analysis methods and experimental techniques for measuring nanomechanical properties with the atomic force microscope (AFM) are considered. These techniques are then applied to the study of cellulose nanoparticles, an abundant, plant derived nanomaterial. Quantifying uncertainty is a prerequisite for the manufacture of reliable nano-engineered materials and products. However, rigorous uncertainty quantification is rarely applied for material property measurements with the AFM. A framework is presented to ascribe uncertainty to local nanomechanical properties of any nanoparticle or surface measured with the AFM by taking into account the main uncertainty sources inherent in such measurements. This method is demonstrated by quantifying uncertainty in force displacement AFM based measurements of the transverse elastic modulus of tunicate cellulose nanocrystals. Next, a more comprehensive study of different types of cellulose nanoparticles is undertaken with contact resonance (CR) AFM. CR-AFM is a dynamic AFM technique that exploits the resonance frequency of the AFM cantilever while it is permanent contact with the sample surface to predict nanomechanical properties. This technique offers improved measurement sensitivity over static AFM methods for some material systems. The effects of cellulose source material and processing technique on the properties of cellulose nanoparticles are compared. Finally, dynamic AFM cantilever vibration shapes are studied. Many AFM modes exploit the dynamic response of a cantilever in permanent contact with a sample to extract local material properties. A common challenge to these modes is that they assume a certain shape of cantilever vibration, which is not accessible in

  19. Atomic physics measurements using an ECR ion source located on a 350-kV high-voltage platform

    SciTech Connect

    Dunford, R.W.; Berry, H.G.; Liu, C.J.; Hass, M.; Pardo, R.C.; Raphaelian, M.L.A.; Zabransky, B.J.

    1988-01-01

    We report on a new atomic physics facility at the Argonne PII ECR ion source which was built for the Uranium Upgrade of the ATLAS heavy-ion accelerator. An important feature of our ECR ion source is that it is on a high-voltage platform which provides beam energies of up to 350q keV, where q is the charge of the ion. We discuss the experimental program in progress at this ion source which includes measurements of state-selective electron capture cross sections, photon and electron spectroscopy, studies of quasi-molecular collisions, and polarization studies using an optically pumped Na target. 9 refs., 6 figs.

  20. PREFACE: 15th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT2013)

    NASA Astrophysics Data System (ADS)

    Wang, Jianxiong

    2014-06-01

    This volume of Journal of Physics: Conference Series is dedicated to scientific contributions presented at the 15th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2013) which took place on 16-21 May 2013 at the Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China. The workshop series brings together computer science researchers and practitioners, and researchers from particle physics and related fields to explore and confront the boundaries of computing and of automatic data analysis and theoretical calculation techniques. This year's edition of the workshop brought together over 120 participants from all over the world. 18 invited speakers presented key topics on the universe in computer, Computing in Earth Sciences, multivariate data analysis, automated computation in Quantum Field Theory as well as computing and data analysis challenges in many fields. Over 70 other talks and posters presented state-of-the-art developments in the areas of the workshop's three tracks: Computing Technologies, Data Analysis Algorithms and Tools, and Computational Techniques in Theoretical Physics. The round table discussions on open-source, knowledge sharing and scientific collaboration stimulate us to think over the issue in the respective areas. ACAT 2013 was generously sponsored by the Chinese Academy of Sciences (CAS), National Natural Science Foundation of China (NFSC), Brookhaven National Laboratory in the USA (BNL), Peking University (PKU), Theoretical Physics Cernter for Science facilities of CAS (TPCSF-CAS) and Sugon. We would like to thank all the participants for their scientific contributions and for the en- thusiastic participation in all its activities of the workshop. Further information on ACAT 2013 can be found at http://acat2013.ihep.ac.cn. Professor Jianxiong Wang Institute of High Energy Physics Chinese Academy of Science Details of committees and sponsors are available in the PDF

  1. Divisible Atoms or None at All? Facing the European Contributions to Developments of Chemistry and Physics in China.

    PubMed

    Južnič, Stanislav

    2016-12-01

    atoms is discussed as possible new paradigm which could rename the destructible divisible entities of future physics, and with more difficulties also of chemistry. The word atom meaning indivisible not compound entity is basically in contradiction with the characteristics of item it is supposed to describe. The suffix "a" provides a negation in Ancient Greek language. The suffix should be omitted to use tom (τομος) to manage the actual situation of a-toms (=Toms) as compound of elementary particles. In late 19th century after the European Spring of Nations actually two basically different concepts of atoms of chemists and physicists accomplished a kind of symbioses. The suggestion is put forward that while indivisible atoms soon became contradictions in physics, they still retain some value in chemistry which should be taken into account in the attempt to hange the name of atom. The research of human genome as the atom of genetics is similar in broader sense, while there is no basic problem with the nomenclature of genome. The genome manipulations are far less obstructed with Chinese traditions compared to Christian beliefs.

  2. Precision Physics of Simple Atoms and Constraints on a Light Boson with Ultraweak Coupling

    SciTech Connect

    Karshenboim, S. G.

    2010-06-04

    Constraint on spin-dependent and spin-independent Yukawa potential at atomic scale is developed. That covers constraints on a coupling constant of an additional photon {gamma}* and a pseudovector boson. The mass range considered is from 1 eV/c{sup 2} to 1 MeV/c{sup 2}. The strongest constraint on a coupling constant {alpha}{sup '} is at the level of a few parts in 10{sup 13} (for {gamma}*) and below one part in 10{sup 16} (for a pseudovector) corresponding to mass below 1 keV/c{sup 2}. The constraints are derived from low-energy tests of quantum electrodynamics and are based on spectroscopic data on light hydrogenlike atoms and experiments with magnetic moments of leptons and light nuclei.

  3. The Physics of Miniature Atomic Clocks: 0-0 Versus "End" Transitions

    NASA Astrophysics Data System (ADS)

    Post, Amber; Jau, Yuan-Yu; Kuzma, Nicholas; Happer, William

    2003-05-01

    The majority of traditional atomic-clock designs are based on the 0-0 hyperfine transition of a Cs 133 atom. We are currently investigating the advantages of operating a miniature optical atomic clock using the "end" transitions, e.g. connecting states |f=1, mf =+/-1> and |f=2, mf=+/-2> in 87Rb. In our paper we present extensive new measurements of relevant relaxation rates, such as those due to spin-exchange collisions, buffer-gas pressure shifts, Carver Rates and others, which ultimately determine the choices of an operating regime for the miniature optical atomic clock. The relationship between these rates is non-trivial: for example, using higher laser power will increase polarization and reduce the spin-exchange rate [1], but it can simultaneously increase the linewidth due to the optical pumping rate. The dependence of these and other relaxation rates on the cell size, temperature, pressure, a choice of buffer gas, and other parameters will be reported. Based on these measured rates, our modeling can be used to predict the transition linewidths, signal-to-noise ratios and thus the stability of the clock in different operating regimes. The trade-off between the stability of the clock and the desired small cell size and low power consumption needs to be carefully considered in order to optimize our design. In our experiments we used optical, microwave, and radio-frequency excitation to study hyperfine and Zeeman resonance lines in heated glass cells containing pure-isotope alkali-metal vapor and buffer gasses (N2, Ar, He, etc.) at low (0 - 10 G) magnetic fields. Simultaneous use of light, microwave and radio-frequency fields allowed us to calibrate surrounding magnetic fields by observing the corresponding shifts of the resonance, thus leading us to a quantitative understanding of our system. [1] S. Appelt, A. B. Baranga, A. R. Young, W. Happer, Phys. Rev. A 59, 2078 (1999).

  4. An electrostatic storage ring for atomic and molecular physics, at KACST - a status report

    NASA Astrophysics Data System (ADS)

    El Ghazaly, Mohamed O. A.

    2015-01-01

    An electrostatic storage ring has been designed following the pioneering storage ring ELISA [1], and it is currently being built as a new core laboratory for atomic and molecular collisions at the King Abdulaziz City for Science and Technology (KACST), in Riyadh, Saudi Arabia. In this paper, the design of the electrostatic storage ring together with an outline on the status of the construction are given.

  5. Underwater Acoustic Wireless Sensor Networks: Advances and Future Trends in Physical, MAC and Routing Layers

    PubMed Central

    Climent, Salvador; Sanchez, Antonio; Capella, Juan Vicente; Meratnia, Nirvana; Serrano, Juan Jose

    2014-01-01

    This survey aims to provide a comprehensive overview of the current research on underwater wireless sensor networks, focusing on the lower layers of the communication stack, and envisions future trends and challenges. It analyzes the current state-of-the-art on the physical, medium access control and routing layers. It summarizes their security threads and surveys the currently proposed studies. Current envisioned niches for further advances in underwater networks research range from efficient, low-power algorithms and modulations to intelligent, energy-aware routing and medium access control protocols. PMID:24399155

  6. The case for advanced physics topics in oral and maxillofacial surgery.

    PubMed

    Tandon, Rahul; Herford, Alan S

    2014-10-01

    Research in oral and maxillofacial surgery has focused mainly on principles founded in the biological and chemical sciences, which have provided excellent answers to many questions. However, recent technologic advances have begun to gain prominence in many of the medical sciences, providing clinicians with more effective tools for diagnosis and treatment. The era of modern physics has led to the development of diagnostic techniques that could provide information at a more basic level than many of the current biochemical methods used. The goal of this report is to introduce 2 of these methods and describe how they can be applied to oral and maxillofacial surgery.

  7. Advanced Physics-Based Modeling of Discrete Clutter and Diffuse Reverberation in the Littoral Environment

    DTIC Science & Technology

    2005-12-01

    2 9 0 V I L L A G E P A R K D R V I E • L E B A N O N , O H • 4 5 0 3 6 - 7 8 8 5 P H O N E : ( 5 1 3 ) 2 2 8 - 0 0 7 3 December 8...DEC 2005 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Advanced Physics- Based Modeling of Discrete Clutter and Diffuse...2400 and 3600 Hz using path a (see Figure 3) shown by the solid blue line, using path e shown by the solid red line and path d shown by the dashed

  8. The problems of solar-terrestrial coupling and new processes introduced to the physics of the ionosphere from the physics of atomic collisions

    NASA Astrophysics Data System (ADS)

    Avakyan, Sergei

    2010-05-01

    Further progress in research of solar-terrestrial coupling requires better understanding of solar variability influence on the ionosphere. The most powerful manifestations of solar variability are solar flares and geomagnetic storms. During a flare EUV/X-ray irradiations are completely absorbed in the ionosphere producing SID. During geomagnetic storms precipitations of electrons with energy of several keV (and to a lesser extent protons precipitations) from radiation belts and geomagnetosphere produce additional ionization and low latitude auroras. Considering the physics of ionosphere during the last several decades we have been taking into account three novel processes well known in the physics of atomic collisions. These are Auger effect [S. V. Avakyan, The consideration of Auger processes in the upper atmosphere of Earth. In Abstracts of paper presented at the Tenth scien. and techn. Conf. of young specialists of S.I. Vavilov State Optical Institute, 1974, 29-31.], multiple photoionization of upper, valence shell [S.V. Avakyan, The source of O++ ions in the upper atmosphere, 1979, Cosmic Res, 17, 942 - 943] and Rydberg excitation of all the components of upper atmosphere [S.V. Avakyan, The new factor in the physics of solar - terrestrial relations - Rydberg atomic and molecules states. Conf. on Physics of solar-terrestrial relationships, 1994, Almaty, 3 - 5]. In the present paper the results of bringing these new processes in the ionospheric physics are discussed and also its possible role in the physics of solar-terrestrial coupling is considered. Involving these processes to the model estimations allowed us for the first time to come to the following important conclusions: - Auger electrons play the determinant role at the formation of energy spectrum of photoelectrons and secondary auroral electrons at the range above 150 eV; - double photoionization of the outer shell of the oxygen atom (by a single photon) plays a dominant role in the formation of

  9. PREFACE: 16th International workshop on Advanced Computing and Analysis Techniques in physics research (ACAT2014)

    NASA Astrophysics Data System (ADS)

    Fiala, L.; Lokajicek, M.; Tumova, N.

    2015-05-01

    This volume of the IOP Conference Series is dedicated to scientific contributions presented at the 16th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2014), this year the motto was ''bridging disciplines''. The conference took place on September 1-5, 2014, at the Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic. The 16th edition of ACAT explored the boundaries of computing system architectures, data analysis algorithmics, automatic calculations, and theoretical calculation technologies. It provided a forum for confronting and exchanging ideas among these fields, where new approaches in computing technologies for scientific research were explored and promoted. This year's edition of the workshop brought together over 140 participants from all over the world. The workshop's 16 invited speakers presented key topics on advanced computing and analysis techniques in physics. During the workshop, 60 talks and 40 posters were presented in three tracks: Computing Technology for Physics Research, Data Analysis - Algorithms and Tools, and Computations in Theoretical Physics: Techniques and Methods. The round table enabled discussions on expanding software, knowledge sharing and scientific collaboration in the respective areas. ACAT 2014 was generously sponsored by Western Digital, Brookhaven National Laboratory, Hewlett Packard, DataDirect Networks, M Computers, Bright Computing, Huawei and PDV-Systemhaus. Special appreciations go to the track liaisons Lorenzo Moneta, Axel Naumann and Grigory Rubtsov for their work on the scientific program and the publication preparation. ACAT's IACC would also like to express its gratitude to all referees for their work on making sure the contributions are published in the proceedings. Our thanks extend to the conference liaisons Andrei Kataev and Jerome Lauret who worked with the local contacts and made this conference possible as well as to the program

  10. Opportunities for Regenerative Rehabilitation and Advanced Technologies in Physical Therapy: Perspective From Academia.

    PubMed

    Norland, Ryan; Muchnick, Matthew; Harmon, Zachary; Chin, Tiffany; Kakar, Rumit Singh

    2016-04-01

    As rehabilitation specialists, physical therapists must continue to stay current with advances in technologies to provide appropriate rehabilitation protocols, improve patient outcomes, and be the preferred clinician of choice. To accomplish this vision, the physical therapy profession must begin to develop a culture of lifelong learning at the early stages of education and clinical training in order to embrace cutting-edge advancements such as stem cell therapies, tissue engineering, and robotics, to name a few. The purposes of this article are: (1) to provide a current perspective on faculty and graduate student awareness of regenerative rehabilitation concepts and (2) to advocate for increased integration of these emerging technologies within the doctor of physical therapy (DPT) curriculum. An online survey was designed to gauge awareness of principles in regenerative rehabilitation and to determine whether the topic was included and assessed in doctoral curricula. The survey yielded 1,006 responses from 82 DPT programs nationwide and indicated a disconnect in familiarity with the term "regenerative rehabilitation" and awareness of the inclusion of this material in the curriculum. To resolve this disconnect, the framework of the curriculum can be used to integrate new material via guest lecturers, interdisciplinary partnerships, and research opportunities. Successfully mentoring a generation of clinicians and rehabilitation scientists who incorporate new medical knowledge and technology into their own clinical and research practice depends greatly on sharing the responsibility among graduate students, professors, the American Physical Therapy Association (APTA), and DPT programs. Creating an interdisciplinary culture and integrating regenerative medicine and rehabilitation concepts into the curriculum will cultivate individuals who will be advocates for interprofessional behaviors and will ensure that the profession meets the goals stated in APTA Vision 2020.

  11. The Scales of Time, Length, Mass, Energy, and Other Fundamental Physical Quantities in the Atomic World and the Use of Atomic Units in Quantum Mechanical Calculations

    ERIC Educational Resources Information Center

    Teo, Boon K.; Li, Wai-Kee

    2011-01-01

    This article is divided into two parts. In the first part, the atomic unit (au) system is introduced and the scales of time, space (length), and speed, as well as those of mass and energy, in the atomic world are discussed. In the second part, the utility of atomic units in quantum mechanical and spectroscopic calculations is illustrated with…

  12. The physics of the environmental sensitivity of rubidium gas cell atomic frequency standards.

    PubMed

    Riley, W R

    1992-01-01

    The physical mechanisms behind environmental sensitivity are considered, and they are related to the performances of rubidium frequency standards (RFSs). Some of the RFS environmental sensitivities are due to simple physical mechanisms like the effect of DC magnetic field on the Rb hyperfine resonance frequency. For these, an analysis can be based on physical principles and straightforward design factors. Other environmental factors, like temperature sensitivity, are more complex combinations of many effects, both physical and practical, and the analysis often takes the form of an error budget, with large unit-to-unit variations. Today's RFSs span a wide performance range from small, inexpensive units with pp10(10) error budgets to larger, higher-performance versions offering pp10(14) stabilities. For both extremes, however, environmental sensitivity can be the most significant performance limitation. Why this is the case is explained, and some insight into how to make improvements is offered.

  13. Workshop on Coupled-Cluster Theory at the Interface of Atomic Physics and Quantum Chemistry

    DTIC Science & Technology

    1991-03-05

    potentials, electron affinities, and Auger spectroscopy, Fock space multi-reference methods (as discussed at the workshop by Mukherjee, Kaldor , Rittby...Bishop K. Jankowski Zuwei Liu University of Manchester Nicholas Capernicus University University of Virginia Dept. of Mathematics Institute of Physics...Kingston, NY 12401 Bhanu Pratap Das Uzi Kaldor Peter Mohr Utah State University Tel Aviv University National Institute of Standards & Physics Dept

  14. Successful aging: Advancing the science of physical independence in older adults.

    PubMed

    Anton, Stephen D; Woods, Adam J; Ashizawa, Tetso; Barb, Diana; Buford, Thomas W; Carter, Christy S; Clark, David J; Cohen, Ronald A; Corbett, Duane B; Cruz-Almeida, Yenisel; Dotson, Vonetta; Ebner, Natalie; Efron, Philip A; Fillingim, Roger B; Foster, Thomas C; Gundermann, David M; Joseph, Anna-Maria; Karabetian, Christy; Leeuwenburgh, Christiaan; Manini, Todd M; Marsiske, Michael; Mankowski, Robert T; Mutchie, Heather L; Perri, Michael G; Ranka, Sanjay; Rashidi, Parisa; Sandesara, Bhanuprasad; Scarpace, Philip J; Sibille, Kimberly T; Solberg, Laurence M; Someya, Shinichi; Uphold, Connie; Wohlgemuth, Stephanie; Wu, Samuel Shangwu; Pahor, Marco

    2015-11-01

    The concept of 'successful aging' has long intrigued the scientific community. Despite this long-standing interest, a consensus definition has proven to be a difficult task, due to the inherent challenge involved in defining such a complex, multi-dimensional phenomenon. The lack of a clear set of defining characteristics for the construct of successful aging has made comparison of findings across studies difficult and has limited advances in aging research. A consensus on markers of successful aging is furthest developed is the domain of physical functioning. For example, walking speed appears to be an excellent surrogate marker of overall health and predicts the maintenance of physical independence, a cornerstone of successful aging. The purpose of the present article is to provide an overview and discussion of specific health conditions, behavioral factors, and biological mechanisms that mark declining mobility and physical function and promising interventions to counter these effects. With life expectancy continuing to increase in the United States and developed countries throughout the world, there is an increasing public health focus on the maintenance of physical independence among all older adults.

  15. Successful Aging: Advancing the Science of Physical Independence in Older Adults

    PubMed Central

    Anton, Stephen D.; Woods, Adam J.; Ashizawa, Tetso; Barb, Diana; Buford, Thomas W.; Carter, Christy S.; Clark, David J.; Cohen, Ronald A.; Corbett, Duane B.; Cruz-Almeida, Yenisel; Dotson, Vonetta; Ebner, Natalie; Efron, Philip A.; Fillingim, Roger B.; Foster, Thomas C.; Gundermann, David M.; Joseph, Anna-Maria; Karabetian, Christy; Leeuwenburgh, Christiaan; Manini, Todd M.; Marsiske, Michael; Mankowski, Robert T.; Mutchie, Heather L.; Perri, Michael G.; Ranka, Sanjay; Rashidi, Parisa; Sandesara, Bhanuprasad; Scarpace, Philip J.; Sibille, Kimberly T.; Solberg, Laurence M.; Someya, Shinichi; Uphold, Connie; Wohlgemuth, Stephanie; Wu, Samuel Shangwu; Pahor, Marco

    2015-01-01

    The concept of ‘Successful Aging’ has long intrigued the scientific community. Despite this long-standing interest, a consensus definition has proven to be a difficult task, due to the inherent challenge involved in defining such a complex, multi-dimensional phenomenon. The lack of a clear set of defining characteristics for the construct of successful aging has made comparison of findings across studies difficult and has limited advances in aging research. The domain in which consensus on markers of successful aging is furthest developed is the domain of physical functioning. For example, walking speed appears to be an excellent surrogate marker of overall health and predicts the maintenance of physical independence, a cornerstone of successful aging. The purpose of the present article is to provide an overview and discussion of specific health conditions, behavioral factors, and biological mechanisms that mark declining mobility and physical function and promising interventions to counter these effects. With life expectancy continuing to increase in the United States and developed countries throughout the world, there is an increasing public health focus on the maintenance of physical independence among all older adults. PMID:26462882

  16. PREFACE: 14th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2011)

    NASA Astrophysics Data System (ADS)

    Teodorescu, Liliana; Britton, David; Glover, Nigel; Heinrich, Gudrun; Lauret, Jérôme; Naumann, Axel; Speer, Thomas; Teixeira-Dias, Pedro

    2012-06-01

    ACAT2011 This volume of Journal of Physics: Conference Series is dedicated to scientific contributions presented at the 14th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2011) which took place on 5-7 September 2011 at Brunel University, UK. The workshop series, which began in 1990 in Lyon, France, brings together computer science researchers and practitioners, and researchers from particle physics and related fields in order to explore and confront the boundaries of computing and of automatic data analysis and theoretical calculation techniques. It is a forum for the exchange of ideas among the fields, exploring and promoting cutting-edge computing, data analysis and theoretical calculation techniques in fundamental physics research. This year's edition of the workshop brought together over 100 participants from all over the world. 14 invited speakers presented key topics on computing ecosystems, cloud computing, multivariate data analysis, symbolic and automatic theoretical calculations as well as computing and data analysis challenges in astrophysics, bioinformatics and musicology. Over 80 other talks and posters presented state-of-the art developments in the areas of the workshop's three tracks: Computing Technologies, Data Analysis Algorithms and Tools, and Computational Techniques in Theoretical Physics. Panel and round table discussions on data management and multivariate data analysis uncovered new ideas and collaboration opportunities in the respective areas. This edition of ACAT was generously sponsored by the Science and Technology Facility Council (STFC), the Institute for Particle Physics Phenomenology (IPPP) at Durham University, Brookhaven National Laboratory in the USA and Dell. We would like to thank all the participants of the workshop for the high level of their scientific contributions and for the enthusiastic participation in all its activities which were, ultimately, the key factors in the

  17. As-Run Physics Analysis for the UCSB-1 Experiment in the Advanced Test Reactor

    SciTech Connect

    Nielsen, Joseph Wayne

    2015-09-01

    The University of California Santa Barbara (UCSB) -1 experiment was irradiated in the A-10 position of the ATR. The experiment was irradiated during cycles 145A, 145B, 146A, and 146B. Capsule 6A was removed from the test train following Cycle 145A and replaced with Capsule 6B. This report documents the as-run physics analysis in support of Post-Irradiation Examination (PIE) of the test. This report documents the as-run fluence and displacements per atom (DPA) for each capsule of the experiment based on as-run operating history of the ATR. Average as-run heating rates for each capsule are also presented in this report to support the thermal analysis.

  18. Spectral and Atomic Physics Analysis of Xenon L-Shell Emission From High Energy Laser Produced Plasmas

    NASA Astrophysics Data System (ADS)

    Thorn, Daniel; Kemp, G. E.; Widmann, K.; Benjamin, R. D.; May, M. J.; Colvin, J. D.; Barrios, M. A.; Fournier, K. B.; Liedahl, D.; Moore, A. S.; Blue, B. E.

    2016-10-01

    The spectrum of the L-shell (n =2) radiation in mid to high-Z ions is useful for probing plasma conditions in the multi-keV temperature range. Xenon in particular with its L-shell radiation centered around 4.5 keV is copiously produced from plasmas with electron temperatures in the 5-10 keV range. We report on a series of time-resolved L-shell Xe spectra measured with the NIF X-ray Spectrometer (NXS) in high-energy long-pulse (>10 ns) laser produced plasmas at the National Ignition Facility. The resolving power of the NXS is sufficiently high (E/ ∂E >100) in the 4-5 keV spectral band that the emission from different charge states is observed. An analysis of the time resolved L-shell spectrum of Xe is presented along with spectral modeling by detailed radiation transport and atomic physics from the SCRAM code and comparison with predictions from HYDRA a radiation-hydrodynamics code with inline atomic-physics from CRETIN. This work was performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.

  19. A note on black-hole physics, cosmic censorship, and the charge-mass relation of atomic nuclei

    NASA Astrophysics Data System (ADS)

    Hod, Shahar

    2016-02-01

    Arguing from the cosmic censorship principle, one of the fundamental cornerstones of black-hole physics, we have recently suggested the existence of a universal upper bound relating the maximal electric charge of a weakly self-gravitating system to its total mass: Z(A)≤slant {Z}*(A)\\equiv {α }-1/3{A}2/3, where Z is the number of protons in the system, A is the total baryon (mass) number, and α ={e}2/{{\\hslash }}c is the dimensionless fine-structure constant. In order to test the validity of this suggested bound, we here explore the Z(A) functional relation of atomic nuclei as deduced from the Weizsäcker semi-empirical mass formula. It is shown that all atomic nuclei, including the meta-stable maximally charged ones, conform to the suggested charge-mass upper bound. Our results support the validity of the cosmic censorship conjecture in black-hole physics.

  20. The application of atomic physics within impurity diagnostics for fusion plasmas

    SciTech Connect

    Loch, S. D.; Ballance, C. P.; Pindzola, M. S.; Griffin, D. C.

    2013-04-19

    With the focus of ITER on the transport and emission properties of tungsten, generating atomic data for complex species has received much interest. Focusing on impurity influx diagnostics, we discuss recent work on heavy species. Perturbative approaches do not work well for near neutral systems so non-perturbative data are required, presenting a particular challenge for these influx diagnostics. Recent results on Mo{sup +} are given as an illustration of how the diagnostic applications can guide the theoretical calculations for such systems.

  1. A driver linac for the Advanced Exotic Beam Laboratory : physics design and beam dynamics simulations.

    SciTech Connect

    Ostroumov, P. N.; Mustapha, B.; Nolen, J.; Physics

    2007-01-01

    The Advanced Exotic Beam Laboratory (AEBL) being developed at ANL consists of an 833 MV heavy-ion driver linac capable of producing uranium ions up to 200 MeV/u and protons to 580 MeV with 400 kW beam power. We have designed all accelerator components including a two charge state LEBT, an RFQ, a MEBT, a superconducting linac, a stripper station and chicane. We present the results of an optimized linac design and end-to-end simulations including machine errors and detailed beam loss analysis. The Advanced Exotic Beam Laboratory (AEBL) has been proposed at ANL as a reduced scale of the original Rare Isotope Accelerator (RIA) project with about half the cost but the same beam power. AEBL will address 90% or more of RIA physics but with reduced multi-users capabilities. The focus of this paper is the physics design and beam dynamics simulations of the AEBL driver linac. The reported results are for a multiple charge state U{sup 238} beam.

  2. Atomic polarizabilities

    SciTech Connect

    Safronova, M. S.; Mitroy, J.; Clark, Charles W.; Kozlov, M. G.

    2015-01-22

    The atomic dipole polarizability governs the first-order response of an atom to an applied electric field. Atomic polarization phenomena impinge upon a number of areas and processes in physics and have been the subject of considerable interest and heightened importance in recent years. In this paper, we will summarize some of the recent applications of atomic polarizability studies. A summary of results for polarizabilities of noble gases, monovalent, and divalent atoms is given. The development of the CI+all-order method that combines configuration interaction and linearized coupled-cluster approaches is discussed.

  3. Engineering development of advanced physical fine coal cleaning for premium fuel applications

    SciTech Connect

    Shields, G.L.; Smit, F.J.; Jha, M.C.

    1997-08-28

    The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope included laboratory research and bench-scale testing on six coals to optimize these processes, followed by the design, construction and operation of 2 t/hr process development unit (PDU). This report represents the findings of the PDU Advanced Column Flotation Testing and Evaluation phase of the program and includes a discussion of the design and construction of the PDU. Three compliance steam coals, Taggart, Indiana VII and Hiawatha, were processed in the PDU to determine performance and design parameters for commercial production of premium fuel by advanced flotation. Consistent, reliable performance of the PDU was demonstrated by 72-hr production runs on each of the test coals. Its capacity generally was limited by the dewatering capacity of the clean coal filters during the production runs rather than by the flotation capacity of the Microcel column. The residual concentrations of As, Pb, and Cl were reduced by at least 25% on a heating value basis from their concentrations in the test coals. The reduction in the concentrations of Be, Cd, Cr, Co, Mn, Hg, Ni and Se varied from coal to coal but the concentrations of most were greatly reduced from the concentrations in the ROM parent coals. The ash fusion temperatures of the Taggart and Indiana VII coals, and to a much lesser extent the Hiawatha coal, were decreased by the cleaning.

  4. Advanced Mesh-Enabled Monte carlo capability for Multi-Physics Reactor Analysis

    SciTech Connect

    Wilson, Paul; Evans, Thomas; Tautges, Tim

    2012-12-24

    This project will accumulate high-precision fluxes throughout reactor geometry on a non- orthogonal grid of cells to support multi-physics coupling, in order to more accurately calculate parameters such as reactivity coefficients and to generate multi-group cross sections. This work will be based upon recent developments to incorporate advanced geometry and mesh capability in a modular Monte Carlo toolkit with computational science technology that is in use in related reactor simulation software development. Coupling this capability with production-scale Monte Carlo radiation transport codes can provide advanced and extensible test-beds for these developments. Continuous energy Monte Carlo methods are generally considered to be the most accurate computational tool for simulating radiation transport in complex geometries, particularly neutron transport in reactors. Nevertheless, there are several limitations for their use in reactor analysis. Most significantly, there is a trade-off between the fidelity of results in phase space, statistical accuracy, and the amount of computer time required for simulation. Consequently, to achieve an acceptable level of statistical convergence in high-fidelity results required for modern coupled multi-physics analysis, the required computer time makes Monte Carlo methods prohibitive for design iterations and detailed whole-core analysis. More subtly, the statistical uncertainty is typically not uniform throughout the domain, and the simulation quality is limited by the regions with the largest statistical uncertainty. In addition, the formulation of neutron scattering laws in continuous energy Monte Carlo methods makes it difficult to calculate adjoint neutron fluxes required to properly determine important reactivity parameters. Finally, most Monte Carlo codes available for reactor analysis have relied on orthogonal hexahedral grids for tallies that do not conform to the geometric boundaries and are thus generally not well

  5. Physics and the New Games -- or Pretend You're an Atom.

    ERIC Educational Resources Information Center

    Edge, Ronald D.

    1982-01-01

    Describes several games in which physics principles are demonstrated using students. These include Pirates Treasure Game (vectors), Three-Meter Dash (kinematics), Knee-Bend Game (energy and power), Wave Game, Reaction Kinematics, Statics-People Pyramids, and games demonstrating nuclear reactions, collisions, electrons in a wire, close packing, and…

  6. Davisson-Germer Prize Talk: Many-Body Physics with Atomic Fermions

    NASA Astrophysics Data System (ADS)

    Hulet, Randall

    2016-05-01

    Ultracold atomic gases confined to optical lattices have proven to be highly versatile and tunable systems for realizing novel quantum states of matter. We are using Fermi gases of 6 Li atoms in our laboratory to explore several goals related to the strong correlations that arise in these systems. We have realized the Hubbard model, which has long been suspected of containing the essential ingredients of high temperature superconductivity. We measured the compressibility of the Mott insulating phase that occurs near half filling (1 atom/site), thus demonstrating the excitation gap of the Mott insulator. Progress in this field, however, has been hampered by an inability to cool to low enough temperatures to achieve the most ambitious goals. To address this problem, we have developed the compensated optical lattice method to enable evaporative cooling in the lattice. With this method, we have cooled the Mott insulator sufficiently far to observe short-range antiferromagnetic correlations using Bragg scattering of light. We are currently exploring new methods for entropy storage and redistribution to achieve even lower entropy in the antiferromagnetic phase. Motivated by the enhancement of quantum correlations in low dimensions, we are also exploring Fermi gases in quasi-one-dimension (1D). A deep 2D optical lattice produces an array of 1D tubes which can be weakly coupled by reducing the lattice depth, thus increasing the lattice hopping t between them. We observe a crossover from 1D-like to 3D-like behavior in the phase separation of a spin-imbalanced Fermi gas with increasing t. While this crossover occurs at a value of t that depends on interaction, we find that the crossover location is universally dependent upon the scaled hopping t /ɛb , where ɛb is the pair binding energy. Finally, I will also report progress on measuring the speed of sound of the charge and spin modes in a 1D Fermi gas. Work supported by an ARO MURI, NSF, and the Robert A Welch Foundation.

  7. The physics of the environmental sensitivity of rubidium gas cell atomic frequency standards

    NASA Technical Reports Server (NTRS)

    Riley, William J.

    1990-01-01

    Environmental sensitivity is often the most significant limitation to the practical stability of rubidium frequency standards (RFS). For example, temperature sensitivity can cause a rapid frequency change of several parts in 10(exp 10) for a tactical RFS that has an aging of only 1 times 10(exp -11)/month. Other important environmental factors are barometric pressure, vibration, magnetic field, and nuclear radiation. The physical mechanisms that lie behind these environmental sensitivities are considered. These physical mechanisms are related to the performance of actual rubidium frequency standards. For the user of these devices, a better knowledge of the causes for Rb clock instability will aid in their testing and proper application. For the time frequency specialist, a review of these factors may prove useful toward improving RFS design. Some of the RFS environmental sensitivities are due to simple physical mechanisms like the effect of dc magnetic field on the Rb hyperfine resonance frequency. For these, an analysis can be based on physical principles and straightforward design factors. Other environment factors, like temperature sensitivity, are more complex combinations of many effects, both physical and practical, and the analysis often takes the form of an error budget with large unit-to-unit variations. Today's rubidium frequency standards span a wide performance range from small, inexpensive units with pp 10(exp 10) error budgets to larger, higher performance versions offering pp 10(exp 10) stabilities. For both extremes, however, environmental sensitivity can be the most significant performance limitation. Why this is the case and how to make improvements are discussed.

  8. The design, development, and assessment of advanced modeling based projects in introductory physics

    NASA Astrophysics Data System (ADS)

    Ramsdell, Michael W.

    The results of Physics Education Research (PER) have provided much insight into developing more effective learning environments in introductory physics courses. In this dissertation we discuss the design, development, and implementation of two advanced Modeling Based Projects (MBP) that have evolved through research-based criteria. The projects serve as an alternative to the traditional laboratory portion of the introductory calculus-based courses taught at Clarkson University for undergraduate science and engineering majors. Each project has gone through several research-redevelopment cycles, through which the experimental apparatuses and pedagogical approaches have been improved. Details of each projects' pedagogical structure and implementation are presented and discussed within the context of recommendations established through PER. We present a detailed assessment of their effectiveness in terms of students' conceptual learning via the Force Concepts Inventory (FCI) and the Conceptual Survey of Electricity and Magnetism (CSEM), course performance via exam scores, and attitudes via the Maryland Physics Expectations Survey (MPEX). The results show that students who participate in MBP at Clarkson University achieve significant gains over students taught elsewhere with a traditional approach and similar gains to those achieved by others using well tested, research motivated curricula reforms. An internal evaluation was performed to compare students participating in MBP with a control group of statistically comparable students who attended traditional laboratories. The results reveal that students who participated in MBP obtain statistically significant gains over similar students taught with the traditional approach for both courses within the introductory sequence.

  9. Point defect dynamics in MOSFETs -- From atomic-scale physics to engineering models

    NASA Astrophysics Data System (ADS)

    Pantelides, Sokrates T.

    2003-03-01

    Dopant impurities are the key ingredient that makes semiconductors so useful in microelectronics. Other point defects, e.g., vacancies and self-interstitial, play major roles in mediating diffusion, which can be both good and bad. Hydrogen is another element that is very useful in passivating point defects at the Si-SiO2 interface of metal-oxide-semiconductor field-effect transistors (MOSFETs), but it also lurks dormant in all kinds of places. Oxygen vacancies also abound dormant and benign in the SiO2 gate layer, but both hydrogen and oxygen vacancies reveal sinister personas when radiation strikes (as in space electronics). This talk will give a brief account of how, over the last few decades, atomic-scale quantum mechanical calculations have impacted the process of constructing engineering models that are used in technology development and then focus on recent results on point defect dynamics in MOSFETs, some of which have been fed into engineering models.

  10. Atomic physics modeling of transmission spectra of Sc-doped aerogel foams to support OMEGA experiments

    NASA Astrophysics Data System (ADS)

    Johns, H. M.; Lanier, N. E.; Kline, J. L.; Fontes, C. J.; Perry, T. S.; Fryer, C. L.; Brown, C. R. D.; Morton, J. W.; Hager, J. D.; Sherrill, M. E.

    2016-11-01

    We present synthetic transmission spectra generated with PrismSPECT utilizing both the ATBASE model and the Los Alamos opacity library (OPLIB) to evaluate whether an alternative choice in atomic data will impact modeling of experimental data from radiation transport experiments using Sc-doped aerogel foams (ScSi6O12 at 75 mg/cm3 density). We have determined that in the 50-200 eV Te range there is a significant difference in the 1s-3p spectra, especially below 100 eV, and for Te = 200 eV above 5000 eV in photon energy. Examining synthetic spectra generated using OPLIB with 300 resolving power reveals spectral sensitivity to Te changes of ˜3 eV.

  11. Physical adsorption: rare gas atoms on solid surfaces. Progress report, June 1, 1980-May 31, 1981

    SciTech Connect

    Cole, M.W.

    1981-02-01

    This project has entailed investigation of three areas during the current term: physical adsorption, photostimulated field emission (PSE), and phonon reflection at interfaces. The principal effort has been directed toward understanding interactions associated with physical adsorption and the associated properties of a film. The specific topics pursued include the detailed form of the long range interaction, the configuration space wave function, and the interaction between adatoms. Experimental confirmation of the last two come from neutron scattering and thermodynamic measurements, respectively. The research in PSE has yielded results which improve upon previous calculations. There is, however, a remaining disagreement with experiment; suggestions for the origin are discussed. The phonon reflection work is directed toward understanding the role of surface roughness, an important factor in increasing the energy transmission across interfaces. A formalism has been developed which will be evaluated in the future.

  12. HISTRAP: Proposal for a Heavy Ion Storage Ring for Atomic Physics

    SciTech Connect

    Not Available

    1988-11-01

    This paper presents an overview of the physics capabilities of HISTRAP together with a brief description of the facility and a sampling of the beams which will be available for experimentation, and surveys some of the lines of investigation in the physics of multicharged ions, molecular ion spectroscopy, condensed beams, and nuclear physics that will become possible with the advent of HISTRAP. Details of the accelerator design are discussed, including computer studies of beam tracking in the HISTRAP lattice, a discussion of the HHIRF tandem and ECR/RFQ injectors, and a description of the electron beam cooling system. In the past three years, HISTRAP has received substantial support from Oak Ridge National Laboratory management and staff. The project has used discretionary funds to develop hardware prototypes and carry out design studies. Construction has been completed on a vacuum test stand which models 1/16 of the storage ring and has attained a pressure of 4 x 10/sup -12/ Torr; a prototype rf cavity capable of accelerating beams up to 90 MeV/nucleon and decelerating to 20 keV/nucleon; and a prototype dipole magnet, one of the eight required for the HISTRAP lattice. This paper also contains a summary of the work on electron cooling carried out by one of our staff members at CERN. Building structures and services are described. Details of cost and schedule are also discussed. 77 refs.

  13. COMPRES Mineral Physics Educational Modules for Advanced Undergraduates and Graduate Students

    NASA Astrophysics Data System (ADS)

    Burnley, P. C.; Thomas, S.

    2012-12-01

    The Consortium for Materials Properties Research in Earth Sciences (COMPRES) is a community-based consortium whose goal is to advance and facilitate experimental high pressure research in the Earth Sciences. An important aspect of this goal is sharing our knowledge with the next generation of researchers. To facilitate this, we have created a group of web-based educational modules on mineral physics topics. The modules reside in the On Cutting Edge, Teaching Mineralogy collection on the Science Education Resource Center (SERC) website. Although the modules are designed to function as part of a full semester course, each module can also stand alone. Potential users of the modules include mineral physics faculty teaching "bricks and mortar" classes at their own institutions, or in distance education setting, mineralogy teachers interested in including supplementary material in their mineralogy class, undergraduates doing independent study projects and graduate students and colleagues in other sub-disciplines who wish to brush up on a mineral physics topic. We used the modules to teach an on-line course entitled "Introduction to Mineral Physics" during the spring 2012 semester. More than 20 students and postdocs as well as 15 faculty and senior scientists participated in the course which met twice weekly as a webinar. Recordings of faculty lectures and student-led discussions of journal articles are now available upon request and edited versions of the lectures will be incorporated into the educational modules. Our experience in creating the modules and the course indicates that the use of 1) community-generated internet-based resources and 2) webinars to enable shared teaching between faculty at different universities, has the potential to both enrich graduate education and create efficiencies for university faculty.;

  14. Atomic Force Microscopy of Physical and Chemical Processes at the Solid-Liquid Interface

    NASA Astrophysics Data System (ADS)

    Manne, Srinivas

    This thesis describes research using atomic force microscopy (AFM) to study dynamics of solid surfaces in contact with liquids. Specifically, three applications are described: electrochemistry (Chapters 1-3), crystal growth (Chapters 4 and 5), and biomineralization (Chapter 6). Chapter 1 shows the feasibility of using AFM to image metal atoms in liquid, which sets the stage for high -resolution electrochemistry. Chapter 2 describes methods to convert the standard AFM liquid cell into an electrochemical cell and shows images of a gold electrode during oxidation/reduction cycling. Chapter 3 follows an electroplating cycle, wherein copper is deposited from electrolyte onto a gold electrode and then stripped off. The surface lattice is shown to change from that of bulk gold to bulk copper during plating, and back to bulk gold after stripping. Moreover, the first monolayer of copper--which deposits at an "underpotential", before the bulk deposition--is shown to have a lattice which differs from the bulk and is electrolyte dependent. Like electrochemistry, the study of crystal growth is also perfectly suited to a surface technique such as AFM. AFM makes it possible to image "elemental steps" (i.e., steps one unit cell thick) on a single crystal and quantify their motion during growth and dissolution. This is illustrated for the inorganic crystal calcite (Chapter 4) and the more fragile organic crystal L-leucine (Chapter 5). In both cases it is shown that step speed is independent of spacing between steps, indicating that motion occurs by direct interaction of the step-site molecules with the solvent. Chapter 5 also describes techniques for growing and imaging organic crystals. Living organisms also use crystal growth, modified by inorganic and organic additives, to grow mineralized structures such as bones, teeth and seashells. In Chapter 6, AFM reveals the three-dimensional structure of the nacreous or pearly layer of mollusc shells by slowly etching away successive

  15. PREFACE: FLUIDOS 2010: XI Meeting on Recent Advances in the Physics of Fluids and their Applications

    NASA Astrophysics Data System (ADS)

    Bove, Italo; Cabeza, Cecilia; Martí, Arturo C.; Sarasúa, Gustavo

    2011-04-01

    The papers published in this volume of the Journal of Physics: Conference Series were selected from the manuscripts submitted to the XI Meeting on Recent Advances in the Physics of Fluids and their Applications (FLUIDOS2010), which was held in Colonia del Sacramento, Uruguay, 3-5 November 2010. FLUIDOS takes place every two years, usually in November, with the aim of gathering together researchers from all areas of the Physics of Fluids, to update themselves on the latest technical developments and applications, share knowledge and stimulate new ideas. This 11th meeting continues the successful experience of the previous ones which were held in different Argentinian cities. For the first time, the meeting was celebrated in Uruguay, more specifically, in the peaceful town of Colonia del Sacramento, designated a World Heritage Site by UNESCO. The conference presented an outstanding program of papers covering the most recent advances in Physics of Fluids in the following areas: General Fluid Dynamics General and non-Newtonian Flows Magnetohydrodynamics Electrohydrodynamics and Plasmas Hydraulics, Thermohydraulics and Multiple Phase Flows A website with full details of the conference program, abstracts and other information can be found at http://fluidos2010.fisica.edu.uy. We would like to thank all the participants, especially those who contributed with talks, posters and manuscripts, for making FLUDOS2010 such a successful conference. Our thanks also go to our colleagues for their support and encouragement, particularly in the refereeing of papers. We would like to acknowledge additional financial support from Comisión Sectorial de Investigación Científica (Universidad de la República, Uruguay), Programa de Desarrollo de las Ciencias Básicas (Uruguay) and the Centro Latinoamericano de Física (CLAF). Our thanks are extended to the local government of Colonia del Sacramento. The next FLUIDOS conference will be held in November 2013, in Buenos Aires, Argentina. We

  16. Serum 25-hydroxyvitamin D and Physical Function in Adults of Advanced Age: The CHS All Stars

    PubMed Central

    Houston, Denise K.; Tooze, Janet A.; Davis, Cralen C.; Chaves, Paulo H. M.; Hirsch, Calvin H.; Robbins, John A.; Arnold, Alice M.; Newman, Anne B.; Kritchevsky, Stephen B.

    2011-01-01

    Objectives To examine the association between 25-hydroxyvitamin D (25[OH]D) and physical function in adults of advanced age. Design Cross-sectional and longitudinal analysis of physical function over 3 years of follow-up in the Cardiovascular Health Study All Stars. Setting Forsyth County, NC; Sacramento County, CA; Washington County, MD; and Allegheny County, PA. Participants Community-dwelling adults aged 77–100 years (n=988). Measurements Serum 25(OH)D, short physical performance battery (SPPB) and grip and knee extensor strength assessed at baseline. Mobility disability (difficulty walking half a mile or up 10 steps) and activities of daily living (ADL) disability were assessed at baseline and every 6 months over 3 years of follow-up. Results 30.8% of participants had deficient 25(OH)D (<20 ng/mL). SPPB scores were lower among those with deficient 25(OH)D compared to those with sufficient 25(OH)D (≥30 ng/mL) after adjusting for sociodemographic characteristics, season, health behaviors and chronic conditions (mean±SE: 6.53±0.24 vs. 7.15±0.25, p <0.01). Grip strength adjusted for body size was also lower among those with deficient versus sufficient 25(OH)D (mean±SE: 24.7±0.6 vs. 26.0±0.6 kg, p <0.05). Participants with deficient 25(OH)D were more likely to have prevalent mobility and ADL disability at baseline (OR (95% CI): 1.44 (0.96–2.14) and 1.51 (1.01–2.25), respectively) compared to those with sufficient 25(OH)D. Furthermore, participants with deficient 25(OH)D were at increased risk of incident mobility disability over 3 years of follow-up (HR (95% CI): 1.56 (1.06–2.30)). Conclusion Vitamin D deficiency was common and was associated with poorer physical performance, lower muscle strength, and prevalent mobility and ADL disability among community-dwelling adults of advanced age. Moreover, vitamin D deficiency predicted incident mobility disability. PMID:22091492

  17. A physical description of fission product behavior fuels for advanced power reactors.

    SciTech Connect

    Kaganas, G.; Rest, J.; Nuclear Engineering Division; Florida International Univ.

    2007-10-18

    The Global Nuclear Energy Partnership (GNEP) is considering a list of reactors and nuclear fuels as part of its chartered initiative. Because many of the candidate materials have not been explored experimentally under the conditions of interest, and in order to economize on program costs, analytical support in the form of combined first principle and mechanistic modeling is highly desirable. The present work is a compilation of mechanistic models developed in order to describe the fission product behavior of irradiated nuclear fuel. The mechanistic nature of the model development allows for the possibility of describing a range of nuclear fuels under varying operating conditions. Key sources include the FASTGRASS code with an application to UO{sub 2} power reactor fuel and the Dispersion Analysis Research Tool (DART ) with an application to uranium-silicide and uranium-molybdenum research reactor fuel. Described behavior mechanisms are divided into subdivisions treating fundamental materials processes under normal operation as well as the effect of transient heating conditions on these processes. Model topics discussed include intra- and intergranular gas-atom and bubble diffusion, bubble nucleation and growth, gas-atom re-solution, fuel swelling and ?scion gas release. In addition, the effect of an evolving microstructure on these processes (e.g., irradiation-induced recrystallization) is considered. The uranium-alloy fuel, U-xPu-Zr, is investigated and behavior mechanisms are proposed for swelling in the {alpha}-, intermediate- and {gamma}-uranium zones of this fuel. The work reviews the FASTGRASS kinetic/mechanistic description of volatile ?scion products and, separately, the basis for the DART calculation of bubble behavior in amorphous fuels. Development areas and applications for physical nuclear fuel models are identified.

  18. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    SciTech Connect

    Not Available

    1993-02-12

    The Department of Energy (DOE) awarded a contract entitled Engineering Development of Advanced Physical Fine Coal Cleaning Technology - Froth Flotation'', to ICF Kaiser Engineers with the following team members, Ohio Coal Development Office, Babcock and Wilcox, Consolidation Coal Company, Eimco Process Equipment Company, Illinois State Geological Survey, Virginia Polytechnic Institute and State University, Process Technology, Inc. This document a quarterly report prepared in accordance with the project reporting requirements covering the period from July 1, 1992 to September 30, 1992. This report provides a summary of the technical work undertaken during this period, highlighting the major results. A brief description of the work done prior to this quarter is provided in this report under the task headings.

  19. Threshold Laws for Two-Electron Ejection Processes: A Still Controversial Problem in Atomic Physics

    NASA Technical Reports Server (NTRS)

    Temkin, Aaron

    2003-01-01

    This talk deals with collision processes of the following kind: (a) an ionizing collision of an electron with a neutral atom, (b) a photon incident of a negative ion resulting in two-electron ejection. In both cases the final state is a positive ion and two outgoing electrons, and in principle both processes should be governed by the same form of threshold law. It is generally conceded that this is one of the most difficult basic problems in nonrelativistic quantum mechanics. The standard treatment (due to Wannier) will be briefly reviewed in terms of the derivation of his well- known threshold law for the yield (Q) of positive ions vs. the excess energy (E): Q(sub w) varies as E(exp 1.127...). The derivation is a brilliant analysis based on Newton's equations, leading to the dominance of events in which the two electrons emerge on opposite sides of the residual ion with similar energies. In contrast, I will argue on the basis of quantum mechanical ideas that in the threshold limit the more likely outcome are events in which the electrons emerge with decidedly different energies, leading to a formally different (Coulomb-dipole) threshold law Q(sub CD) varies as E(1 + C sin(alpha ln(E)+mu)]/[ln(E)](exp 2). Additional aspects of that approach will be discussed . Some: experimental results will be presented, and more incisive predictions involving polarized projectiles and targets will be given.

  20. Numerical Aspects of Atomic Physics: Helium Basis Sets and Matrix Diagonalization

    NASA Astrophysics Data System (ADS)

    Jentschura, Ulrich; Noble, Jonathan

    2014-03-01

    We present a matrix diagonalization algorithm for complex symmetric matrices, which can be used in order to determine the resonance energies of auto-ionizing states of comparatively simple quantum many-body systems such as helium. The algorithm is based in multi-precision arithmetic and proceeds via a tridiagonalization of the complex symmetric (not necessarily Hermitian) input matrix using generalized Householder transformations. Example calculations involving so-called PT-symmetric quantum systems lead to reference values which pertain to the imaginary cubic perturbation (the imaginary cubic anharmonic oscillator). We then proceed to novel basis sets for the helium atom and present results for Bethe logarithms in hydrogen and helium, obtained using the enhanced numerical techniques. Some intricacies of ``canned'' algorithms such as those used in LAPACK will be discussed. Our algorithm, for complex symmetric matrices such as those describing cubic resonances after complex scaling, is faster than LAPACK's built-in routines, for specific classes of input matrices. It also offer flexibility in terms of the calculation of the so-called implicit shift, which is used in order to ``pivot'' the system toward the convergence to diagonal form. We conclude with a wider overview.

  1. First atomic physics experiments with cooled stored ion beams at the Heidelberg heavy-ion ring TSR

    SciTech Connect

    Wolf, A.; Balykin, V.; Baumann, W.; Berger, J.; Bisoffi, G.; Blatt, P.; Blum, M.; Faulstich, A.; Friedrich, A.; Gerhard, M.; Geyer, C.; Grieser, M.; Grieser, R.; Habs, D.; Heyng, H.W.; Hochadel, B.; Holzer, B.; Huber, G.; Jaeschke, E.; Jung, M.; Karafillidis, A.; Kilgus, G.; Klein, R.; Kraemer, D.; Krause, P.; Krieg, M.; Kuehl, T.; Matl, K.; Mueller, A.; Music, M.; Neumann, R.; Neureither, G.; Ott, W.; Petrich, W.; Povh, B.; Repnow, R.; Schroeder, S.; Schuch, R.; Schwalm, D.; Sigray, P.; Steck, M.; Stokstad, R.; Szmola, E.; Wagner, M.; Wanner, B.; Welti, K.; Zwickler, S. Max-Planck-Institut fuer Kernphysik, Heidelberg Manne Siegbahn Institute , Stockholm Institut fuer Kernphysik, Universitaet Giessen, Institut fuer Physik, Universitaet Mainz Gesellschaft fuer Schwerionenforschung , Darmstadt (Fed

    1990-06-01

    An overview of atomic physics experiments at the heavy ion Test Storage Ring (TSR) is given. Highly charged ions up to fully stripped silicon have been stored at energies between 4 and 12 MeV/u. The enhancement of the beam intensity by stacking, the beam lifetime, and electron cooling of these ion beams are discussed. Radiative and state-selective dielectronic recombination rates of hydrogen-like oxygen ions with free electrons from the electron cooler were measured. Beam noise spectra are being investigated with regard to collective effects caused by the Coulomb interaction in the cold ion beams. Resonance fluorescence from stored single-charged ions was observed using tunable narrow-band lasers. First indications of laser cooling in a storage ring were seen.

  2. A new data acquisition system for Schottky signals in atomic physics experiments at GSI's and FAIR's storage rings

    NASA Astrophysics Data System (ADS)

    Trageser, C.; Brandau, C.; Kozhuharov, C.; Litvinov, Yu A.; Müller, A.; Nolden, F.; Sanjari, S.; Stöhlker, T.

    2015-11-01

    A new continuous and broadband data acquisition system for measurements of Schottky-signals of ions revolving in a storage ring has been implemented. This set-up is capable of recording the radio frequency (RF) signal of the ions that circulate in the storage ring with a sustained acquisition rate of more than 3.5× {10}7 IQ-samples per second. This allows several harmonics of the full momentum acceptance of a storage ring to be measured at the same time. The RF signal analyzer modules are complemented by further electronic modules such as counters, precision clocks and synchronization modules that facilitate a seamless integration with main experimental data acquisitions for atomic and nuclear physics. In this contribution, the setup and first results from a test run at the experimental storage ring at GSI, Darmstadt, Germany, are presented.

  3. Using Recent Planetary Science Data to Develop Advanced Undergraduate Physics and Astronomy Activities

    NASA Astrophysics Data System (ADS)

    Steckloff, Jordan; Lindell, Rebecca

    2016-10-01

    Teaching science by having students manipulate real data is a popular trend in astronomy and planetary science education. However, many existing activities simply couple this data with traditional "cookbook" style verification labs. As with most topics within science, this instructional technique does not enhance the average students' understanding of the phenomena being studied. Here we present a methodology for developing "science by doing" activities that incorporate the latest discoveries in planetary science with up-to-date constructivist pedagogy to teach advanced concepts in Physics and Astronomy. In our methodology, students are first guided to understand, analyze, and plot real raw scientific data; develop and test physical and computational models to understand and interpret the data; finally use their models to make predictions about the topic being studied and test it with real data.To date, two activities have been developed according to this methodology: Understanding Asteroids through their Light Curves (hereafter "Asteroid Activity"), and Understanding Exoplanetary Systems through Simple Harmonic Motion (hereafter "Exoplanet Activity"). The Asteroid Activity allows students to explore light curves available on the Asteroid Light Curve Database (ALCDB) to discover general properties of asteroids, including their internal structure, strength, and mechanism of asteroid moon formation. The Exoplanet Activity allows students to investigate the masses and semi-major axes of exoplanets in a system by comparing the radial velocity motion of their host star to that of a coupled simple harmonic oscillator. Students then explore how noncircular orbits lead to deviations from simple harmonic motion. These activities will be field tested during the Fall 2016 semester in an advanced undergraduate mechanics and astronomy courses at a large Midwestern STEM-focused university. We will present the development methodologies for these activities, description of the

  4. Atomic radiations in the decay of medical radioisotopes: a physics perspective.

    PubMed

    Lee, B Q; Kibédi, T; Stuchbery, A E; Robertson, K A

    2012-01-01

    Auger electrons emitted in nuclear decay offer a unique tool to treat cancer cells at the scale of a DNA molecule. Over the last forty years many aspects of this promising research goal have been explored, however it is still not in the phase of serious clinical trials. In this paper, we review the physical processes of Auger emission in nuclear decay and present a new model being developed to evaluate the energy spectrum of Auger electrons, and hence overcome the limitations of existing computations.

  5. Atomic Radiations in the Decay of Medical Radioisotopes: A Physics Perspective

    PubMed Central

    Lee, B. Q.; Kibédi, T.; Stuchbery, A. E.; Robertson, K. A.

    2012-01-01

    Auger electrons emitted in nuclear decay offer a unique tool to treat cancer cells at the scale of a DNA molecule. Over the last forty years many aspects of this promising research goal have been explored, however it is still not in the phase of serious clinical trials. In this paper, we review the physical processes of Auger emission in nuclear decay and present a new model being developed to evaluate the energy spectrum of Auger electrons, and hence overcome the limitations of existing computations. PMID:22924061

  6. Monte Carlo Simulations in Statistical Physics -- From Basic Principles to Advanced Applications

    NASA Astrophysics Data System (ADS)

    Janke, Wolfhard

    2013-08-01

    This chapter starts with an overview of Monte Carlo computer simulation methodologies which are illustrated for the simple case of the Ising model. After reviewing importance sampling schemes based on Markov chains and standard local update rules (Metropolis, Glauber, heat-bath), nonlocal cluster-update algorithms are explained which drastically reduce the problem of critical slowing down at second-order phase transitions and thus improve the performance of simulations. How this can be quantified is explained in the section on statistical error analyses of simulation data including the effect of temporal correlations and autocorrelation times. Histogram reweighting methods are explained in the next section. Eventually, more advanced generalized ensemble methods (simulated and parallel tempering, multicanonical ensemble, Wang-Landau method) are discussed which are particularly important for simulations of first-order phase transitions and, in general, of systems with rare-event states. The setup of scaling and finite-size scaling analyses is the content of the following section. The chapter concludes with two advanced applications to complex physical systems. The first example deals with a quenched, diluted ferromagnet, and in the second application we consider the adsorption properties of macromolecules such as polymers and proteins to solid substrates. Such systems often require especially tailored algorithms for their efficient and successful simulation.

  7. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    SciTech Connect

    Not Available

    1990-01-01

    a study conducted by Pittsburgh Energy Technology Center of sulfur emissions from about 1300 United States coal-fired utility boilers indicated that half of the emissions were the result of burning coals having greater than 1.2 pounds of SO{sub 2} per million BTU. This was mainly attributed to the high pyritic sulfur content of the boiler fuel. A significant reduction in SO{sub 2} emissions could be accomplished by removing the pyrite from the coals by advanced physical fine coal cleaning. An engineering development project was prepared to build upon the basic research effort conducted under a solicitation for research into Fine Coal Surface Control. The engineering development project is intended to use general plant design knowledge and conceptualize a plant to utilize advanced froth flotation technology to process coal and produce a product having maximum practical pyritic sulfur reduction consistent with maximum practical BTU recovery. This document is the eighth quarterly report prepared in accordance with the project reporting requirements covering the period from July 1,1990 to September 30, 1990. The overall project scope of the engineering development project is to conceptually develop a commercial flowsheet to maximize pyritic sulfur reduction at practical energy recovery values. The data from the basic research on coal surfaces, bench scale testing and proof-of-concept scale testing will be utilized to design a final conceptual flowsheet. The economics of the flowsheet will be determined to enable industry to assess the feasibility of incorporating the advanced fine coal cleaning technology into the production of clean coal for generating electricity. 22 figs., 11 tabs.

  8. Physical bounds of metallic nanofingers obtained by mechano-chemical atomic force microscope nanolithography

    NASA Astrophysics Data System (ADS)

    Akhavan, O.; Abdolahad, M.

    2009-01-01

    To obtain metallic nanofingers applicable in surface acoustic wave (SAW) sensors, a mechano-chemical atomic force microscope (AFM) nanolithography on a metallic thin film (50 nm in thickness)/piezoelectric substrate covered by a spin-coated polymeric mask layer (50-60 nm in thickness) was implemented. The effective shape of cross-section of the before and after etching grooves have been determined by using the AFM tip deconvolution surface analysis, structure factor, and power spectral density analyses. The wet-etching process improved the shape and aspect ratio (height/width) of the grooves and also smoothed the surface within them. We have shown that the relaxed surface tension of the polymeric mask layer resulted in a down limitation in width and length of the lithographed nanofingers. The surface tension of the mask layer can be changed by altering the initial concentration of the polymer in the deposition process. As the surface tension reduced, the down limitation decreased. In fact, an extrapolation of the analyzed statistical data has indicated that by decreasing the surface tension from 39 to 10 nN/nm, the minimum obtainable width and length of the metallic nanofingers was changed from about 55 nm and 2 μm to 15 nm and 0.44 μm, respectively. Using the extrapolation's results, we have shown that the future SAW sensors buildable by this nanolithography method possess a practical bound in their synchronous frequency (˜58 GHz), mass sensitivity (˜6125 MHz-mm 2/ng), and the limit of mass resolution (˜4.88 × 10 -10 ng/mm 2).

  9. A NATIONAL COLLABORATORY TO ADVANCE THE SCIENCE OF HIGH TEMPERATURE PLASMA PHYSICS FOR MAGNETIC FUSION

    SciTech Connect

    Allen R. Sanderson; Christopher R. Johnson

    2006-08-01

    This report summarizes the work of the University of Utah, which was a member of the National Fusion Collaboratory (NFC) Project funded by the United States Department of Energy (DOE) under the Scientific Discovery through Advanced Computing Program (SciDAC) to develop a persistent infrastructure to enable scientific collaboration for magnetic fusion research. A five year project that was initiated in 2001, it the NFC built on the past collaborative work performed within the U.S. fusion community and added the component of computer science research done with the USDOE Office of Science, Office of Advanced Scientific Computer Research. The project was itself a collaboration, itself uniting fusion scientists from General Atomics, MIT, and PPPL and computer scientists from ANL, LBNL, and Princeton University, and the University of Utah to form a coordinated team. The group leveraged existing computer science technology where possible and extended or created new capabilities where required. The complete finial report is attached as an addendum. The In the collaboration, the primary technical responsibility of the University of Utah in the collaboration was to develop and deploy an advanced scientific visualization service. To achieve this goal, the SCIRun Problem Solving Environment (PSE) is used on FusionGrid for an advanced scientific visualization service. SCIRun is open source software that gives the user the ability to create complex 3D visualizations and 2D graphics. This capability allows for the exploration of complex simulation results and the comparison of simulation and experimental data. SCIRun on FusionGrid gives the scientist a no-license-cost visualization capability that rivals present day commercial visualization packages. To accelerate the usage of SCIRun within the fusion community, a stand-alone application built on top of SCIRun was developed and deployed. This application, FusionViewer, allows users who are unfamiliar with SCIRun to quickly create

  10. ENGINEERING DEVELOPMENT OF ADVANCED PHYSICAL FINE COAL CLEANING FOR PREMIUM FUEL APPLICATIONS

    SciTech Connect

    none,

    1997-06-01

    Bechtel, together with Amax Research and Development Center (Amax R&D), has prepared this study which provides conceptual cost estimates for the production of premium quality coal-water slurry fuel (CWF) in a commercial plant. Two scenarios are presented, one using column flotation technology and the other the selective agglomeration to clean the coal to the required quality specifications. This study forms part of US Department of Energy program "Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications," (Contract No. DE-AC22- 92PC92208), under Task 11, Project Final Report. The primary objective of the Department of Energy program is to develop the design base for prototype commercial advanced fine coal cleaning facilities capable of producing ultra-clean coals suitable for conversion to stable and highly loaded CWF. The fuels should contain less than 2 lb ash/MBtu (860 grams ash/GJ) of HHV and preferably less than 1 lb ash/MBtu (430 grams ash/GJ). The advanced fine coal cleaning technologies to be employed are advanced column froth flotation and selective agglomeration. It is further stipulated that operating conditions during the advanced cleaning process should recover not less than 80 percent of the carbon content (heating value) in the run-of-mine source coal. These goals for ultra-clean coal quality are to be met under the constraint that annualized coal production costs does not exceed $2.5 /MBtu ($ 2.37/GJ), including the mine mouth cost of the raw coal. A further objective of the program is to determine the distribution of a selected suite of eleven toxic trace elements between product CWF and the refuse stream of the cleaning processes. Laboratory, bench-scale and Process Development Unit (PDU) tests to evaluate advanced column flotation and selective agglomeration were completed earlier under this program with selected coal samples. A PDU with a capacity of 2 st/h was designed by Bechtel and installed at Amax R

  11. IBPRO - A Novel Short-Duration Teaching Course in Advanced Physics and Biology Underlying Cancer Radiotherapy.

    PubMed

    Joiner, Michael C; Tracey, Monica W; Kacin, Sara E; Burmeister, Jay W

    2017-03-22

    This article provides a summary and status report of the ongoing advanced education program IBPRO - Integrated course in Biology and Physics of Radiation Oncology. IBPRO is a five-year program funded by NCI. It addresses the recognized deficiency in the number of mentors available who have the required knowledge and skill to provide the teaching and training that is required for future radiation oncologists and researchers in radiation sciences. Each year, IBPRO brings together 50 attendees typically at assistant professor level and upwards, who are already qualified/certified radiation oncologists, medical physicists or biologists. These attendees receive keynote lectures and activities based on active learning strategies, merging together the clinical, biological and physics underpinnings of radiation oncology, at the forefront of the field. This experience is aimed at increasing collaborations, raising the level and amount of basic and applied research undertaken in radiation oncology, and enabling attendees to confidently become involved in the future teaching and training of researchers and radiation oncologists.

  12. MO-FG-BRC-00: Joint AAPM-ESTRO Symposium: Advances in Experimental Medical Physics.

    PubMed

    Berbeco, Ross; Ionascu, Dan

    2016-06-01

    Experimental research in medical physics has expanded the limits of our knowledge and provided novel imaging and therapy technologies for patients around the world. However, experimental efforts are challenging due to constraints in funding, space, time and other forms of institutional support. In this joint ESTRO-AAPM symposium, four exciting experimental projects from four different countries are highlighted. Each project is focused on a different aspect of radiation therapy. From the USA, we will hear about a new linear accelerator concept for more compact and efficient therapy devices. From Canada, we will learn about novel linear accelerator target design and the implications for imaging and therapy. From France, we will discover a mature translational effort to incorporate theranostic nanoparticles in MR-guided radiation therapy. From Germany, we will find out about a novel in-treatment imaging modality for particle therapy. These examples of high impact, experimental medical physics research are representative of the diversity of such efforts that are on-going around the globe. J. Robar, Research is supported through collaboration with Varian Medical Systems and Brainlab AGD. Westerly, This work is supported by the Department of Radiation Oncology at the University of Colorado School of Medicine. COI: NONEK. Parodi, Part of the presented work is supported by the DFG (German Research Foundation) Cluster of Excellence MAP (Munich-Centre for Advanced Photonics) and has been carried out in collaboration with IBA.

  13. FIRE, A Test Bed for ARIES-RS/AT Advanced Physics and Plasma Technology

    SciTech Connect

    Dale M. Meade

    2004-10-21

    The overall vision for FIRE [Fusion Ignition Research Experiment] is to develop and test the fusion plasma physics and plasma technologies needed to realize capabilities of the ARIES-RS/AT power plant designs. The mission of FIRE is to attain, explore, understand and optimize a fusion dominated plasma which would be satisfied by producing D-T [deuterium-tritium] fusion plasmas with nominal fusion gains {approx}10, self-driven currents of {approx}80%, fusion power {approx}150-300 MW, and pulse lengths up to 40 s. Achieving these goals will require the deployment of several key fusion technologies under conditions approaching those of ARIES-RS/AT. The FIRE plasma configuration with strong plasma shaping, a double null pumped divertor and all metal plasma-facing components is a 40% scale model of the ARIES-RS/AT plasma configuration. ''Steady-state'' advanced tokamak modes in FIRE with high beta, high bootstrap fraction, and 100% noninductive current drive are suitable for testing the physics of the ARIES-RS/A T operating modes. The development of techniques to handle power plant relevant exhaust power while maintaining low tritium inventory is a major objective for a burning plasma experiment. The FIRE high-confinement modes and AT-modes result in fusion power densities from 3-10 MWm{sup -3} and neutron wall loading from 2-4 MWm{sup -2} which are at the levels expected from the ARIES-RS/AT design studies.

  14. Metal intoxication in humans assessed by atomic and nuclear physics techniques

    NASA Astrophysics Data System (ADS)

    Chettle, David R.

    1995-08-01

    Toxic trace elements such as lead (Pb) and Cadmium (Cd) can be measured non-invasively in humans by radiation physics techniques, particularly x-ray fluorescence and neutron activation. An analysis is usually made of the content of a particular organ, representing the principal storage site of the element in question. For example, Pb is measured in bone, whereas Cd is measured in liver and kidney. Measuring stored quantities of these elements has contributed to assessment of health effects of chronic occupational and environmental exposure. In addition knowledge of the elemental metabolism has been significantly extended. Results of in vivo studies have also contributed to assessment and regulation of workplace exposure. Analogous methods are in use or under development for in vivo assay of mercury, aluminum, gold, platinum, and manganese. The principles of these measurements will be outlined and illustrative applications for Pb and Cd will be discussed.

  15. Ultracold atoms and their applications (Scientific session of the Physical Sciences Division of the Russian Academy of Sciences, 28 October 2015)

    NASA Astrophysics Data System (ADS)

    2016-02-01

    A scientific session of the Physical Sciences Division of the Russian Academy of Sciences (RAS), "Ultracold atoms and their applications", was held in the conference hall of the Lebedev Physical Institute, RAS, on 28 October 2015.The papers collected in this issue were written based on talks given at the session:(1) Vishnyakova G A, Golovizin A A, Kalganova E S, Tregubov D O, Khabarova K Yu (Lebedev Physical Institute, Russian Academy of Sciences, Moscow; Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow region), Sorokin V N, Sukachev D D, Kolachevsky N N (Lebedev Physical Institute, Russian Academy of Sciences, Moscow) "Ultracold lanthanides: from optical clock to a quantum simulator"; (2) Barmashova T V, Martiyanov K A, Makhalov V B (Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod), Turlapov A V (Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod; Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod) "Fermi liquid to Bose condensate crossover in a two-dimensional ultracold gas experiment"; (3) Taichenachev A V, Yudin V I, Bagayev S N (Institute of Laser Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk; Novosibirsk State University, Novosibirsk) "Ultraprecise optical frequency standards based on ultracold atoms: state of the art and prospects"; (4) Ryabtsev I I, Beterov I I, Tretyakov D B, Entin V M, Yakshina E A (Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk; Novosibirsk State University, Novosibirsk) "Spectroscopy of cold rubidium Rydberg atoms for applications in quantum information". • Ultracold lanthanides: from optical clock to a quantum simulator, G A Vishnyakova, A A Golovizin, E S Kalganova, V N Sorokin, D D Sukachev, D O Tregubov, K Yu Khabarova, N N Kolachevsky Physics-Uspekhi, 2016, Volume 59, Number 2, Pages 168-173 • Fermi liquid-to-Bose condensate crossover in a two

  16. Advances in Galactic Dynamics: Classical Physics in the 21st Century

    NASA Astrophysics Data System (ADS)

    Dubinski, John

    2007-04-01

    During the past 2 decades, there have been tremendous advances in computational power and algorithmic efficiency in the numerical N-body problem. Despite the vast scale of the universe, the original Newtonian equations of motion along with the inverse-square law of gravity still provide an adequate physical framework for studying many of the complexities of the dynamic universe. The relativistic limit in the macroscopic universe is only reached on the extreme scales of the entire observable universe and the event horizons of black holes. Here I will review some of the recent advances in parallel computational algorithms for application to the collisionless N-body problem with the main applications to the problem of the dynamics of galaxies and cosmological structure formation. The cosmological paradigm of cold dark matter with a cosmological constant is now so well-constrained that in principle detailed predictions of the dynamical behavior of galaxies can be tested against observation. I will describe two recent studies that use realistic, self-consistent N-body models of disk galaxies to study the effects of two cosmological predictions: dark matter halo triaxiality and substructure. The reaction of a stellar disk to these dark matter characteristics leads to triggering of the bar instability at random times in a given galaxy's life history and so can help explain the observed fraction and incidence of bars in the spiral galaxy population. I will also present some recent work on high-resolution computer animation of galactic dynamics that originated as a way to illustrate and develop intuition about dynamical processes but has since developed into a means of artistic expression through the beauty of complex gravitating systems.

  17. Integrating atomic layer deposition and ultra-high vacuum physical vapor deposition for in situ fabrication of tunnel junctions.

    PubMed

    Elliot, Alan J; Malek, Gary A; Lu, Rongtao; Han, Siyuan; Yu, Haifeng; Zhao, Shiping; Wu, Judy Z

    2014-07-01

    Atomic Layer Deposition (ALD) is a promising technique for growing ultrathin, pristine dielectrics on metal substrates, which is essential to many electronic devices. Tunnel junctions are an excellent example which require a leak-free, ultrathin dielectric tunnel barrier of typical thickness around 1 nm between two metal electrodes. A challenge in the development of ultrathin dielectric tunnel barriers using ALD is controlling the nucleation of dielectrics on metals with minimal formation of native oxides at the metal surface for high-quality interfaces between the tunnel barrier and metal electrodes. This poses a critical need for integrating ALD with ultra-high vacuum (UHV) physical vapor deposition. In order to address these challenges, a viscous-flow ALD chamber was designed and interfaced to an UHV magnetron sputtering chamber via a load lock. A sample transportation system was implemented for in situ sample transfer between the ALD, load lock, and sputtering chambers. Using this integrated ALD-UHV sputtering system, superconductor-insulator-superconductor (SIS) Nb-Al/Al2O2/Nb Josephson tunnel junctions were fabricated with tunnel barriers of thickness varied from sub-nm to ~1 nm. The suitability of using an Al wetting layer for initiation of the ALD Al2O3 tunnel barrier was investigated with ellipsometry, atomic force microscopy, and electrical transport measurements. With optimized processing conditions, leak-free SIS tunnel junctions were obtained, demonstrating the viability of this integrated ALD-UHV sputtering system for the fabrication of tunnel junctions and devices comprised of metal-dielectric-metal multilayers.

  18. Integrating atomic layer deposition and ultra-high vacuum physical vapor deposition for in situ fabrication of tunnel junctions

    SciTech Connect

    Elliot, Alan J. E-mail: jwu@ku.edu; Malek, Gary A.; Lu, Rongtao; Han, Siyuan; Wu, Judy Z. E-mail: jwu@ku.edu; Yu, Haifeng; Zhao, Shiping

    2014-07-15

    Atomic Layer Deposition (ALD) is a promising technique for growing ultrathin, pristine dielectrics on metal substrates, which is essential to many electronic devices. Tunnel junctions are an excellent example which require a leak-free, ultrathin dielectric tunnel barrier of typical thickness around 1 nm between two metal electrodes. A challenge in the development of ultrathin dielectric tunnel barriers using ALD is controlling the nucleation of dielectrics on metals with minimal formation of native oxides at the metal surface for high-quality interfaces between the tunnel barrier and metal electrodes. This poses a critical need for integrating ALD with ultra-high vacuum (UHV) physical vapor deposition. In order to address these challenges, a viscous-flow ALD chamber was designed and interfaced to an UHV magnetron sputtering chamber via a load lock. A sample transportation system was implemented for in situ sample transfer between the ALD, load lock, and sputtering chambers. Using this integrated ALD-UHV sputtering system, superconductor-insulator-superconductor (SIS) Nb-Al/Al{sub 2}O{sub 2}/Nb Josephson tunnel junctions were fabricated with tunnel barriers of thickness varied from sub-nm to ∼1 nm. The suitability of using an Al wetting layer for initiation of the ALD Al{sub 2}O{sub 3} tunnel barrier was investigated with ellipsometry, atomic force microscopy, and electrical transport measurements. With optimized processing conditions, leak-free SIS tunnel junctions were obtained, demonstrating the viability of this integrated ALD-UHV sputtering system for the fabrication of tunnel junctions and devices comprised of metal-dielectric-metal multilayers.

  19. The Light at the End of the Tunnel: Uncertainties in Atomic Physics, Bayesian Inference, and the Analysis of Solar and Stellar Observations

    NASA Astrophysics Data System (ADS)

    Warren, Harry

    2016-05-01

    We report on the efforts of a multidisciplinary International Space Science Institute team that is investigating the limits of our ability to infer the physical properties of solar and stellar atmospheres from remote sensing observations. As part of this project we have estimated the uncertainties in the collisional cross sections and radiative decay rates for Fe XIII and O VII and created 1000 realizations of the CHIANTI atomic database. These perturbed atomic data are then used to analyze solar observations from the EIS spectrometer on Hinode and stellar observations from the LETG on Chandra within a Bayesian framework. For the solar case we find that the systematic errors from the atomic physics dominate the statistical uncertainties from the observations. For many cases the uncertainties are about 10 times larger when variations in the atomic data are included. This indicates the need for very accurate atomic physics. Comparisons among recent Fe XIII calculations suggest that for some transitions the collision rates are currently known well enough to measure the electron density and emission measure to about 15%.

  20. Investigation of the Flow Physics Driving Stall-Side Flutter in Advanced Forward Swept Fan Designs

    NASA Technical Reports Server (NTRS)

    Sanders, Albert J.; Liu, Jong S.; Panovsky, Josef; Bakhle, Milind A.; Stefko, George; Srivastava, Rakesh

    2003-01-01

    Flutter-free operation of advanced transonic fan designs continues to be a challenging task for the designers of aircraft engines. In order to meet the demands of increased performance and lighter weight, these modern fan designs usually feature low-aspect ratio shroudless rotor blade designs that make the task of achieving adequate flutter margin even more challenging for the aeroelastician. This is especially true for advanced forward swept designs that encompass an entirely new design space compared to previous experience. Fortunately, advances in unsteady computational fluid dynamic (CFD) techniques over the past decade now provide an analysis capability that can be used to quantitatively assess the aeroelastic characteristics of these next generation fans during the design cycle. For aeroelastic applications, Mississippi State University and NASA Glenn Research Center have developed the CFD code TURBO-AE. This code is a time-accurate three-dimensional Euler/Navier-Stokes unsteady flow solver developed for axial-flow turbomachinery that can model multiple blade rows undergoing harmonic oscillations with arbitrary interblade phase angles, i.e., nodal diameter patterns. Details of the code can be found in Chen et al. (1993, 1994), Bakhle et al. (1997, 1998), and Srivastava et al. (1999). To assess aeroelastic stability, the work-per-cycle from TURBO-AE is converted to the critical damping ratio since this value is more physically meaningful, with both the unsteady normal pressure and viscous shear forces included in the work-per-cycle calculation. If the total damping (aerodynamic plus mechanical) is negative, then the blade is unstable since it extracts energy from the flow field over the vibration cycle. TURBO-AE is an integral part of an aeroelastic design system being developed at Honeywell Engines, Systems & Services for flutter and forced response predictions, with test cases from development rig and engine tests being used to validate its predictive

  1. Local density probing of atomic gas via cold Li-Ca+ inelastic collisions in an atom-ion hybrid system

    NASA Astrophysics Data System (ADS)

    Saito, Ryoichi; Haze, Shinsuke; Fujinaga, Munekazu; Kyuno, Kazuki; Mukaiyama, Takashi

    2015-05-01

    Ultracold atoms in a harmonic trap inevitably has an inhomogeneous density distribution, which makes an atomic gas an ensemble of atoms in different physical phases. Recent technical advances in the determination of local physical quantities in an atomic gas overcome this complexity and make it possible to directly compare experimental results with many-body theories of a homogeneous atomic gas. A laser-cooled ion can be used as a high-spatial resolution probe of physical quantities of an atomic gas. The spatial spread of an ion can be reduced to sub-microns, which is even small enough for the application of the local probe of atoms in optical lattices. In our experiment, we constructed Li and Ca+ ultracold hybrid system and observed inelastic collisions as a loss of ions. The inelastic collision is confirmed to be a charge-exchange process, whose rate depends linearly on the local atomic density. From the measurement of the rate of the charge-exchange, we can reproduce an atomic density profile. This is an important step toward a local probe of physical quantities of atoms with cold ions. In this presentation, we report on the observation of charge-exchange collisions between Li atom and Ca+ ions, and discuss the feasibility of the ions as a probe of the atoms.

  2. Quantum information with Rydberg atoms

    SciTech Connect

    Saffman, M.; Walker, T. G.; Moelmer, K.

    2010-07-15

    Rydberg atoms with principal quantum number n>>1 have exaggerated atomic properties including dipole-dipole interactions that scale as n{sup 4} and radiative lifetimes that scale as n{sup 3}. It was proposed a decade ago to take advantage of these properties to implement quantum gates between neutral atom qubits. The availability of a strong long-range interaction that can be coherently turned on and off is an enabling resource for a wide range of quantum information tasks stretching far beyond the original gate proposal. Rydberg enabled capabilities include long-range two-qubit gates, collective encoding of multiqubit registers, implementation of robust light-atom quantum interfaces, and the potential for simulating quantum many-body physics. The advances of the last decade are reviewed, covering both theoretical and experimental aspects of Rydberg-mediated quantum information processing.

  3. A Reconstruction of Structure of the Atom and Its Implications for General Physics Textbooks: A History and Philosophy of Science Perspective

    ERIC Educational Resources Information Center

    Rodriguez, Maria A.; Niaz, Mansoor

    2004-01-01

    Recent research in science education has recognized the importance of history and philosophy of science. The objective of this study is to evaluate the presentation of the Thomson, Rutherford, and Bohr models of the atom in general physics textbooks based on criteria derived from history and philosophy of science. Forty-one general physics…

  4. An investigation into the effect of spray drying temperature and atomizing conditions on miscibility, physical stability, and performance of naproxen-PVP K 25 solid dispersions.

    PubMed

    Paudel, Amrit; Loyson, Yves; Van den Mooter, Guy

    2013-04-01

    The present study investigates the effect of changing spray drying temperature (40°C-120°C) and/or atomizing airflow rate (AR; 5-15 L/min) on the phase structure, physical stability, and performance of spray-dried naproxen-polyvinylpyrrolidone (PVP) K 25 amorphous solid dispersions. The modulated differential scanning calorimetry, attenuated total internal reflectance-Fourier transform infrared, and powder X-ray diffractometry (pXRD) studies revealed that higher inlet temperature (IT) or atomization airflow leads to the formation of amorphous-phase-separated dispersions with higher strongly H-bonded and free PVP fractions, whereas that prepared with the lowest IT was more homogeneous. The dispersion prepared with the lowest atomization AR showed trace crystallinity. Upon exposure to 75% relative humidity (RH) for 3 weeks, the phase-separated dispersions generated by spray drying at higher temperature or higher atomization airflow retained relatively higher amorphous drug fraction compared with those prepared at slow evaporation conditions. The humidity-controlled pXRD analysis at 98% RH showed that the dispersion prepared with highest atomization AR displayed the slowest kinetics of recrystallization. The molecular-level changes occurring during recrystallization at 98% RH was elucidated by spectroscopic monitoring at the same humidity. The rate and extent of the drug dissolution was the highest for dispersions prepared at the highest atomizing AR and the lowest for that prepared with the slowest atomizing condition.

  5. PREFACE: The 19th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases Preface: The 19th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases

    NASA Astrophysics Data System (ADS)

    Gordillo-Vazquez, F. J.

    2009-07-01

    The 19th Europhysics Sectional Conference on the Atomic and Molecular Physics of Ionized Gases (ESCAMPIG-2008) took place in Granada (Spain) from 15 to 19 July 2008. The conference was mainly organized by the Spanish National Research Council (CSIC), with the collaboration and support of the University of Córdoba (UCO) and the Research Center for Energy, Environment and Technology (CIEMAT). It is already 35 years since the first ESCAMPIG in 1973. The first editions of ESCAMPIG were in consecutive years (1973 and 1974) but later on it became a biennial conference of the European Physical Society (EPS) initially focusing on the collisional and radiative atomic and molecular processes in low temperature plasmas. The successive ESCAMPIGs took place in Bratislava in 1976 (3rd), Essen in 1978 (4th), Dubrovnik in 1980 (5th) and so on until the last one organized in Granada in 2008 (19th), the first ESCAMPIG in Spain. A number of changes have taken place in the Granada edition of ESCAMPIG. First, the previous six topics that have remained unchanged for almost two decades (since 1990) have now been updated to become twelve new topics which, in the opinion of the International Scientific Committee (ISC), will enhance the opportunity for discussions and communication of new findings and developments in the field of low temperature plasmas. The new list of topics for ESCAMPIG is: • Atomic and molecular processes in plasmas • Transport phenomena, particle velocity distribution function • Physical basis of plasma chemistry • Plasma surface interaction (boundary layers, sheath, surface processes) • Plasma diagnostics • Plasma and dicharges theory and simulation • Self-organization in plasmas, dusty plasmas • Upper atmospheric plasmas and space plasmas • Low pressure plasma sources • High pressure plasma sources • Plasmas and gas flows • Laser produced plasmas Secondly, a new prize has been created, the `William Crookes' prize in Plasma Physics to be

  6. Presenting the Bohr Atom.

    ERIC Educational Resources Information Center

    Haendler, Blanca L.

    1982-01-01

    Discusses the importance of teaching the Bohr atom at both freshman and advanced levels. Focuses on the development of Bohr's ideas, derivation of the energies of the stationary states, and the Bohr atom in the chemistry curriculum. (SK)

  7. EDITORIAL: The 20th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases The 20th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases

    NASA Astrophysics Data System (ADS)

    Petrović, Zoran Lj; Marić, Dragana; Malović, Gordana

    2011-03-01

    This special issue consists of papers that are associated with invited lectures, workshop papers and hot topic papers presented at the 20th European Sectional Conference on Atomic and Molecular Physics of Ionized Gases (ESCAMPIG XX). This conference was organized in Novi Sad (Serbia) from 13 to 17 July 2010 by the Institute of Physics of the University of Belgrade. It is important to note that this is not a conference 'proceedings'. Following the initial selection process by the International Scientific Committee, all papers were submitted to the journal by the authors and have been fully peer reviewed to the standard required for publication in Plasma Sources Science and Technology (PSST). The papers are based on presentations given at the conference but are intended to be specialized technical papers covering all or part of the topic presented by the author during the meeting. The ESCAMPIG conference is a regular biennial Europhysics Conference of the European Physical Society focusing on collisional and radiative aspects of atomic and molecular physics in partially ionized gases as well as on plasma-surface interaction. The conference focuses on low-temperature plasma sciences in general and includes the following topics: Atomic and molecular processes in plasmas Transport phenomena, particle velocity distribution function Physical basis of plasma chemistry Plasma surface interaction (boundary layers, sheath, surface processes) Plasma diagnostics Plasma and discharges theory and simulation Self-organization in plasmas, dusty plasmas Upper atmospheric plasmas and space plasmas Low-pressure plasma sources High-pressure plasma sources Plasmas and gas flows Laser-produced plasmas During ESCAMPIG XX special sessions were dedicated to workshops on: Atomic and molecular collision data for plasma modeling, organized by Professors Z Lj Petrovic and N Mason Plasmas in medicine, organized by Dr N Puac and Professor G Fridman. The conference topics were represented in the

  8. On the physical interconnection of Seismic Electric Signals with seismicity: Recent advances

    NASA Astrophysics Data System (ADS)

    Sarlis, Nicholas; Skordas, Efthimios; Lazaridou, Mary; Varotsos, Panayiotis

    2013-04-01

    We review the recent advances on Seismic Electric Signals (SES) which are low frequency (˜ 1Hz) signals that precede earthquakes [1-3]. Since the 1980's Varotsos and Alexopoulos proposed [4] that SES are generated in the future focal area when the stress reaches a critical value, thus causing a cooperative orientation of the electric dipoles that anyhow exist in the focal area due to lattice imperfections in the ionic constituents of the rocks. A series of such signals within a short time are termed SES activity [5] and usually appear before major earthquakes. The combination of their physical properties enable the determination of the epicentral region and the magnitude well in advance. Natural time analysis introduced a decade ago [6, 7] may uncover novel dynamic features hidden behind time series in complex systems [8]. By employing this analysis, several advances have been made towards a better understanding of the SES properties. For example, it has been found [6, 8] that the natural time analysis of the seismicity subsequent to the initiation of a SES activity enables the determination of the occurrence time of an impending major mainshock within a time window of around one week. On this basis, predictions -including the magnitude, epicenter and time window of the expected event- have been documented well in advance for all five mainshocks with M_w×6.4 in Greece since 2001 [8, 9]. In addition, by applying natural time analysis to the time series of earthquakes, we recently found [10] that the order parameter of seismicity exhibits a unique change approximately at the date at which SES activities have been reported to initiate. This is the first time that before the occurrence of major earthquakes, anomalous changes are found to appear almost simultaneously in two different geophysical observables. 1. P. Varotsos and K. Alexopoulos, Tectonophysics 110, 73-98, 1984a. 2. P. Varotsos and K. Alexopoulos, Tectonophysics 110, 99-125, 1984b. 3. P.A. Varotsos, N

  9. Mechanical, thermal, and physical properties of Mg-Ca compounds in the framework of the modified embedded-atom method.

    PubMed

    Groh, Sébastien

    2015-02-01

    Interatomic potentials for pure Ca and the Mg-Ca binary have been developed in the framework of the second nearest-neighbors modified embedded-atom method (MEAM). The validity and the transferability of the Ca MEAM potential was performed by calculating physical, mechanical, and thermal properties. These properties were compared to experimental data and numerical data obtained from existing Ca potentials, and a good agreement was found. In addition, the dissociation of the edge dislocation into two Shockley partials aligns with the linear elasticity solution. Furthermore, the velocity of an edge dislocation under static and dynamics loading conditions predicted in Ca using the MEAM formalism reproduces the expected behavior of an edge dislocation in fcc crystal structures. The Ca MEAM potential was then coupled to an existing Mg MEAM potential to describe the properties of the Mg-Ca alloys. Heat of formation, structural energy difference, and elastic constants were calculated for several ordered Mg-Ca compounds containing different concentrations of Ca. As expected from first-principle calculations based on DFT, Mg2Ca with the Laves phase C14 was found to be the most stable structure with the lowest heat of formation compared to compounds with other Ca concentrations (Mg3Ca, MgCa, and MgCa3). Moreover, the mechanical stability was recovered for the different tested compounds and is in agreement with first-principle data.

  10. Atoms in astronomy

    NASA Technical Reports Server (NTRS)

    Blanchard, P. A.

    1976-01-01

    Aspects of electromagnetic radiation and atomic physics needed for an understanding of astronomical applications are explored. Although intended primarily for teachers, this brochure is written so that it can be distributed to students if desired. The first section, Basic Topics, is suitable for a ninth-grade general science class; the style is simple and repetitive, and no mathematics or physics background is required. The second section, Intermediate and Advanced Topics, requires a knowledge of the material in the first section and assumes a generally higher level of achievement and motivation on the part of the student. These latter topics might fit well into junior-level physics, chemistry, or earth-science courses. Also included are a glossary, a list of references and teaching aids, class exercises, and a question and answer section.

  11. Positron Physics

    NASA Technical Reports Server (NTRS)

    Drachman, Richard J.

    2003-01-01

    I will give a review of the history of low-energy positron physics, experimental and theoretical, concentrating on the type of work pioneered by John Humberston and the positronics group at University College. This subject became a legitimate subfield of atomic physics under the enthusiastic direction of the late Sir Harrie Massey, and it attracted a diverse following throughout the world. At first purely theoretical, the subject has now expanded to include high brightness beams of low-energy positrons, positronium beams, and, lately, experiments involving anti-hydrogen atoms. The theory requires a certain type of persistence in its practitioners, as well as an eagerness to try new mathematical and numerical techniques. I will conclude with a short summary of some of the most interesting recent advances.

  12. The consequences of using advanced physical assessment skills in medical and surgical nursing: A hermeneutic pragmatic study

    PubMed Central

    Zambas, Shelaine I.; Smythe, Elizabeth A.; Koziol-Mclain, Jane

    2016-01-01

    Aims and objectives The aim of this study was to explore the consequences of the nurse's use of advanced assessment skills on medical and surgical wards. Background Appropriate, accurate, and timely assessment by nurses is the cornerstone of maintaining patient safety in hospitals. The inclusion of “advanced” physical assessment skills such as auscultation, palpation, and percussion is thought to better prepare nurses for complex patient presentations within a wide range of clinical situations. Design This qualitative study used a hermeneutic pragmatic approach. Method Unstructured interviews were conducted with five experienced medical and surgical nurses to obtain 13 detailed narratives of assessment practice. Narratives were analyzed using Van Manen's six-step approach to identify the consequences of the nurse's use of advanced assessment skills. Results The consequences of using advanced assessment skills include looking for more, challenging interpretations, and perseverance. The use of advanced assessment skills directs what the nurse looks for, what she sees, interpretation of the findings, and her response. It is the interpretation of what is seen, heard, or felt within the full context of the patient situation, which is the advanced skill. Conclusion Advanced assessment skill is the means to an accurate interpretation of the clinical situation and contributes to appropriate diagnosis and medical management in complex patient situations. Relevance to clinical practice The nurse's use of advanced assessment skills enables her to contribute to diagnostic reasoning within the acute medical and surgical setting. PMID:27607193

  13. Advanced gas atomization production of oxide dispersion strengthened (ODS) Ni-base superalloys through process and solidification control

    NASA Astrophysics Data System (ADS)

    Meyer, John Louis Lamb

    A novel gas atomization reaction synthesis (GARS) method was utilized to produce precursor Ni-Cr-Y-Ti powder with a surface oxide and an internal rare earth (RE)-containing intermetallic. Although Al is necessary for industrial superalloy production, the Ni-Cr base alloy system was selected as a simplified system more amenable to characterization. This was done in an effort to better study the effects of processing parameters. Consolidation and heat-treatment were performed to promote the exchange of oxygen from the surface oxide to the RE intermetallic to form nanometric oxide dispersoids. Alloy selection was aided by an internal oxidation and serial grinding experiment that found that Hf-containing alloys may form more stable dispersoids than Ti-containing alloys, but the Hf-containing system exhibited five different oxide phases and two different intermetallics compared to the two oxide phases and one intermetallic in the Ti-containing alloys. Since the simpler Ti-containing system was easier to characterize, and make observations on the effects of processing parameters, the Ti-containing system was used for experimental atomization trials. An internal oxidation model was used to predict the heat treatment times necessary for dispersoid formation as a function of powder size and temperature. A new high-pressure gas atomization (HPGA) nozzle was developed with the aim of promoting fine powder production at scales similar to that of the high gas-flow and melt-flow of industrial atomizers. The atomization nozzle was characterized using schlieren imaging and aspiration pressure testing to determine the optimum melt delivery tip geometry and atomization pressure to promote enhanced secondary atomization mechanisms. Six atomization trials were performed to investigate the effects of gas atomization pressure and reactive-gas concentration on the particle size distribution (PSD). Also, the effect on the rapidly solidified microstructure (as a function of powder size

  14. Relations of morale and physical function to advanced activities of daily living in health promotion class participants

    PubMed Central

    Yajima, Masahide; Asakawa, Yasuyoshi; Yamaguchi, Haruyasu

    2016-01-01

    [Purpose] The aim of this study was to clarify the relations of morale and physical function to the presence/absence of advanced activities of daily living. [Subjects] The subjects were 86 elderly community residents participating in health promotion classes. [Methods] A questionnaire survey on age, gender, presence/absence of advanced activities of daily living, and Philadelphia Geriatric Center Morale Scale score was conducted, in addition to assessment of fitness, consisting of measurement of height, body weight, grip and knee extensor muscle strength, functional reach, one-leg standing time, and Timed Up and Go test. Furthermore, multiple logistic regression analysis was performed with the presence/absence of advanced activities of daily living as a dependent variable. [Results] Grip strength and Timed Up and Go time were identified as variables influencing the presence/absence of advanced activities of daily living. [Conclusion] Physical function represented by grip strength and Timed Up and Go time was higher among subjects performing advanced activities of daily living. PMID:27065541

  15. The Nature of Atoms.

    ERIC Educational Resources Information Center

    Holden, Alan

    This monograph was written for the purpose of presenting physics to college students who are not preparing for careers in physics. It deals with the nature of atoms, and treats the following topics: (1) the atomic hypothesis, (2) the chemical elements, (3) models of an atom, (4) a particle in a one-dimensional well, (5) a particle in a central…

  16. [The application of inductively coupled plasma atomic emission spectrometry/mass spectrometry to the analysis of advanced ceramic materials].

    PubMed

    Wang, Zheng; Wang, Shi-Wei; Qiu, De-Ren; Yang, Peng-Yuan

    2009-10-01

    Advanced ceramics have been applied to various important fields such as information science, aeronautics and astronautics, and life sciences. However, the optics and electric properties of ceramics are significantly affected by the micro and trace impurities existing in the material even at very low concentration level. Thus, the accurate determination of impurities is important for materials preparation and performance. Methodology of the analysis of advanced ceramic materials using ICP-AES/MS was reviewed in the present paper for the past decade. Various techniques of sample introduction, especially advances in the authors' recent work, are described in detail. The developing trend is also presented. Sixty references are cited.

  17. Lars Onsager Prize Talk: A New Challenge for Cold Atom Physics: Achieving the Strongly Correlated Regimes for Cold Atoms in Optical Lattices.

    NASA Astrophysics Data System (ADS)

    Ho, Tin-Lun

    2008-03-01

    Cold atoms in optical lattices show great promise to generate a whole host of new strongly correlated states and to emulate many theoretical models for strongly interacting electronic systems. However, to reach these strongly correlated regimes, we need to reach unprecedented low temperatures within current experimental settings. To achieve this, it is necessary to remove considerable amount of entropy from the system. Here, we point out a general principle for removing entropies of quantum gases in optical lattices which will allow one to reach some extraordinarily low temperature scales.

  18. Engineering development of advanced physical fine coal cleaning for premium fuel applications. Quarterly report, April 1--June 30, 1997

    SciTech Connect

    Moro, N.; Shields, G.L.; Smit, F.J.; Jha, M.C.

    1997-12-31

    The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by the design, construction, and operation of a 2 t/hr process development unit (PDU). Accomplishments during the quarter are described on the following tasks and subtasks: Development of near-term applications (engineering development and dewatering studies); Engineering development of selective agglomeration (bench-scale testing and process scale-up); PDU and advanced column flotation module (coal selection and procurement and advanced flotation topical report); Selective agglomeration module (module operation and clean coal production with Hiawatha, Taggart, and Indiana 7 coals); Disposition of the PDU; and Project final report. Plans for next quarter are discussed and agglomeration results of the three tested coals are presented.

  19. Atom Skimmers and Atom Lasers Utilizing Them

    NASA Technical Reports Server (NTRS)

    Hulet, Randall; Tollett, Jeff; Franke, Kurt; Moss, Steve; Sackett, Charles; Gerton, Jordan; Ghaffari, Bita; McAlexander, W.; Strecker, K.; Homan, D.

    2005-01-01

    Atom skimmers are devices that act as low-pass velocity filters for atoms in thermal atomic beams. An atom skimmer operating in conjunction with a suitable thermal atomic-beam source (e.g., an oven in which cesium is heated) can serve as a source of slow atoms for a magneto-optical trap or other apparatus in an atomic-physics experiment. Phenomena that are studied in such apparatuses include Bose-Einstein condensation of atomic gases, spectra of trapped atoms, and collisions of slowly moving atoms. An atom skimmer includes a curved, low-thermal-conduction tube that leads from the outlet of a thermal atomic-beam source to the inlet of a magneto-optical trap or other device in which the selected low-velocity atoms are to be used. Permanent rare-earth magnets are placed around the tube in a yoke of high-magnetic-permeability material to establish a quadrupole or octupole magnetic field leading from the source to the trap. The atoms are attracted to the locus of minimum magnetic-field intensity in the middle of the tube, and the gradient of the magnetic field provides centripetal force that guides the atoms around the curve along the axis of the tube. The threshold velocity for guiding is dictated by the gradient of the magnetic field and the radius of curvature of the tube. Atoms moving at lesser velocities are successfully guided; faster atoms strike the tube wall and are lost from the beam.

  20. Ion-Atom Cold Collisions and Atomic Clocks

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Maleki, Lute; Tjoelker, Robert L.

    1997-01-01

    Collisions between ultracold neutral atoms have for some time been the subject of investigation, initially with hydrogen and more recently with laser cooled alkali atoms. Advances in laser cooling and trapping of neutral atoms in a Magneto-Optic Trap (MOT) have made cold atoms available as the starting point for many laser cooled atomic physics investigations. The most spectacularly successful of these, the observation of Bose-Einstein Condensation (BEC) in a dilute ultra-cold spin polarized atomic vapor, has accelerated the study of cold collisions. Experimental and theoretical studies of BEC and the long range interaction between cold alkali atoms is at the boundary of atomic and low temperature physics. Such studies have been difficult and would not have been possible without the development and advancement of laser cooling and trapping of neutral atoms. By contrast, ion-atom interactions at low temperature, also very difficult to study prior to modern day laser cooling, have remained largely unexplored. But now, many laboratories worldwide have almost routine access to cold neutral atoms. The combined technologies of ion trapping, together with laser cooling of neutrals has made these studies experimentally feasible and several very important, novel applications might come out of such investigations . This paper is an investigation of ion-atom interactions in the cold and ultra-cold temperature regime. Some of the collisional ion-atom interactions present at room temperature are very much reduced in the low temperature regime. Reaction rates for charge transfer between unlike atoms, A + B(+) approaches A(+) + B, are expected to fall rapidly with temperature, approximately as T(sup 5/2). Thus, cold mixtures of atoms and ions are expected to coexist for very long times, unlike room temperature mixtures of the same ion-atom combination. Thus, it seems feasible to cool ions via collisions with laser cooled atoms. Many of the conventional collisional interactions

  1. PREFACE: X Meeting on Recent Advances in the Physics of Fluids and their Applications

    NASA Astrophysics Data System (ADS)

    Saita, Fernando Adolfo; Giavedoni, María Delia

    2009-07-01

    The X Meeting on Recent Advances in Physics of Fluids and Related Applications (Fluids 2008) was held in Santa Fe, Argentina, on 19-21 November 2008. It belongs to a series of meetings that started in 1989 and has continued - except for just one occasion - every other year. Thus, the first meeting took place in the city of Tandil in 1989 followed by three events in the city of La Plata (1991-93-95), Tunuyán (Mendoza) in 1997, Paraná (Entre Rios) in 1999, Buenos Aires in 2001, Tandil in 2003 and Mendoza in 2006. These meetings gather together most of the people working in Fluid Mechanics and related problems in Argentina. The objective of the meetings is to provide a forum to facilitate the interactions between participants in a friendly academic atmosphere. This goal is achieved by means of lectures and technical presentations on different subjects and from different points of view, the only constraint being the current academic/technical interest. Applications usually deal with problems of local interest. In the present meeting a variety of lecture topics were presented, among them we might mention Capillary Hydrodynamics, Wetting, Density Currents, Instabilities, Elastic-Dynamics, Flows in Porous Media, Sediment Transport, Plasma Dynamics, etc. In particular, we would like to highlight the specially invited lectures given by Dr Ramon Cerro (Chemical and Material Engineering Department University of Alabama in Huntsville, USA), Dr David Quéré (Physique et Mécanique des Milieux Hétérogènes ESPCI, FRANCE), Dr Marcelo García (College of Engineering University of Illinois at Urbana-Champaign) and Dr Víctor Calo (Earth and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST) and Institute for Computational Engineering and Sciences (ICES), University of Texas at Austin). In addition, we had 18 invited talks and more than fifty contributions that were presented in poster sessions. On behalf of both the Honorary

  2. International Conference on Atomic Physics: Abstracts of Contributed Papers (12th) Held in Ann Arbor, Michigan on 29 July-3 August 1990

    DTIC Science & Technology

    1990-09-26

    the local physics of the 2 1Ne nucleus . Systematic variations of the quadrupole component at multiples of the earth’s solar frequency do arise, mostly...equation is justified when the thermalization by wal Collisions drives the atomic velocity distribution to equilibrium on a time scale that is slow...inelastic cavity collisions in which particles can either lose energy or annihilate for a distribution of initial o-Ps energies. We expect such a

  3. Reviews Book: Sustainable Energy—Without the Hot Air Equipment: Doppler Effect Unit Book: The Physics of Rugby Book: Plastic Fantastic: How the Biggest Fraud in Physics Shook the Scientific World Equipment: Brunel Eyecam Equipment: 200x Digital Microscope Book: The Atom and the Apple: Twelve Tales from Contemporary Physics Book: Physics 2 for OCR Web Watch

    NASA Astrophysics Data System (ADS)

    2009-09-01

    WE RECOMMEND Sustainable Energy—Without the Hot Air This excellent book makes sense of energy facts and figures Doppler Effect Unit Another simple, effective piece of kit from SEP Plastic Fantastic: How the Biggest Fraud in Physics Shook the Scientific World Intriguing and unique write-up of an intellectual fraud case Brunel Eyecam An affordable digital eyepiece for your microscope 200x Digital Microscope An adjustable digital flexcam for classroom use The Atom and the Apple: Twelve Tales from Contemporary Physics A fascinating round-up of the recent history of physics WORTH A LOOK The Physics of Rugby Book uses sport analogy and context to teach physics concepts Physics 2 for OCR Essential textbook for the course but otherwise pointless WEB WATCH Some free teaching materials are better than those you'd pay for

  4. Preface to Special Topic: Advances in Radio Frequency Physics in Fusion Plasmas

    SciTech Connect

    Tuccillo, Angelo A.; Ceccuzzi, Silvio; Phillips, Cynthia K.

    2014-06-15

    It has long been recognized that auxiliary plasma heating will be required to achieve the high temperature, high density conditions within a magnetically confined plasma in which a fusion “burn” may be sustained by copious fusion reactions. Consequently, the application of radio and microwave frequency electromagnetic waves to magnetically confined plasma, commonly referred to as RF, has been a major part of the program almost since its inception in the 1950s. These RF waves provide heating, current drive, plasma profile control, and Magnetohydrodynamics (MHD) stabilization. Fusion experiments employ electromagnetic radiation in a wide range of frequencies, from tens of MHz to hundreds of GHz. The fusion devices containing the plasma are typically tori, axisymmetric or non, in which the equilibrium magnetic fields are composed of a strong toroidal magnetic field generated by external coils, and a poloidal field created, at least in the symmetric configurations, by currents flowing in the plasma. The waves are excited in the peripheral regions of the plasma, by specially designed launching structures, and subsequently propagate into the core regions, where resonant wave-plasma interactions produce localized heating or other modification of the local equilibrium profiles. Experimental studies coupled with the development of theoretical models and advanced simulation codes over the past 40+ years have led to an unprecedented understanding of the physics of RF heating and current drive in the core of magnetic fusion devices. Nevertheless, there are serious gaps in our knowledge base that continue to have a negative impact on the success of ongoing experiments and that must be resolved as the program progresses to the next generation devices and ultimately to “demo” and “fusion power plant.” A serious gap, at least in the ion cyclotron (IC) range of frequencies and partially in the lower hybrid frequency ranges, is the difficulty in coupling large amount of

  5. Engineering design and analysis of advanced physical fine coal cleaning technologies

    SciTech Connect

    Gallier, P.W.

    1992-10-20

    The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies- advanced cylconing, selective agglomeration, and advanced froth flotation through the proof-of-concept. The commercially available ASPEN PLUS process simulation package will be extended to handle coal cleaning applications. Algorithms for predicting the process performance, equipment size, and flowsheet economics of commercial coal cleaning devices and related ancillary equipment will be incorporated into the coal cleaning simulator. This report is submitted to document the progress of Aspen Technology Inc. (AspenTech), its contractor, ICF Kaiser Engineers, Inc., (ICF KE) and CQ Inc., for the period of July through September 1992. ICF KE is providing coal preparation consulting and processing engineering services in this work and they are responsible for recommending the design of models to represent conventional coal cleaning equipment and costing of these models. CQ Inc. is a subcontractor to ICF KE on Tasks I - 5 and is a contractor to AspenTech on Task 6.

  6. An Advanced Objective Structured Clinical Examination Using Patient Simulators to Evaluate Pharmacy Students’ Skills in Physical Assessment

    PubMed Central

    Takamura, Norito; Ogata, Kenji; Setoguchi, Nao; Utsumi, Miho; Kourogi, Yasuyuki; Osaki, Takashi; Ozaki, Mineo; Sato, Keizo; Arimori, Kazuhiko

    2014-01-01

    Objective. To implement an advanced objective structured clinical examination (OSCE) in the curriculum and to evaluate Japanese pharmacy students’ skills in physical assessment such as measuring pulse and blood pressure, and assessing heart, lung, and intestinal sounds. Design. An advanced OSCE was implemented in a hospital pharmacy seminar as a compulsory subject. We programmed patient simulators with 21 different patient cases in which normal and abnormal physiological conditions were produced. The virtual patients were then used to evaluate the physical assessment skills of fifth-year pharmacy students. Assessment. Significant differences were observed between the average of all the detailed evaluations and the mean results for the following skills: pulse measurement, blood pressure measurement, deflating the cuff at a rate of 2-3 mmHg/sec, listening to heart sounds, and listening to lung sounds. Conclusion. Administering an advanced OSCE using virtual patients was an effective way of assessing pharmacy students’ skills in a realistic setting. Several areas in which pharmacy students require further training were identified. PMID:25657371

  7. A comparative analysis of teacher-authored websites in high school honors and Advanced Placement physics for Web-design and NSES content and process standards

    NASA Astrophysics Data System (ADS)

    Persin, Ronald C.

    The purpose of this study was to investigate whether statistically significant differences existed between high school Honors Physics websites and those of Advanced Placement (AP) Physics in terms of Web-design, National Science Education Standards (NSES) Physics content, and NSES Science Process standards. The procedure began with the selection of 152 sites comprising two groups with equal sample sizes of 76 for Honors Physics and for Advanced Placement Physics. The websites used in the study were accumulated using the Google(TM) search engine. To find Honors Physics websites, the search words "honors physics high school" were entered as the query into the search engine. To find sites for Advanced Placement Physics, the query, "advanced placement physics high school," was entered into the search engine. The evaluation of each website was performed using an instrument developed by the researcher based on three attributes: Web-design, NSES Physics content, and NSES Science Process standards. A "1" was scored if the website was found to have each attribute, otherwise a "0" was given. This process continued until all 76 websites were evaluated for each of the two types of physics websites, Honors and Advanced Placement. Subsequently the data were processed using Excel functions and the SPSS statistical software program. The mean and standard deviation were computed individually for the three attributes under consideration. Three, 2-tailed, independent samples t tests were performed to compare the two groups of physics websites separately on the basis of Web Design, Physics Content, and Science Process. The results of the study indicated that there was only one statistically significant difference between high school Honors Physics websites and those of AP Physics. The only difference detected was in terms of National Science Education Standards Physics content. It was found that Advanced Placement Physics websites contained more NSES physics content than Honors

  8. An advanced fabrication method of highly ordered ZnO nanowire arrays on silicon substrates by atomic layer deposition.

    PubMed

    Subannajui, Kittitat; Güder, Firat; Danhof, Julia; Menzel, Andreas; Yang, Yang; Kirste, Lutz; Wang, Chunyu; Cimalla, Volker; Schwarz, Ulrich; Zacharias, Margit

    2012-06-15

    In this work, the controlled fabrication of highly ordered ZnO nanowire (NW) arrays on silicon substrates is reported. Si NWs fabricated by a combination of phase shift lithography and etching are used as a template and are subsequently substituted by ZnO NWs with a dry-etching technique and atomic layer deposition. This fabrication technique allows the vertical ZnO NWs to be fabricated on 4 in Si wafers. Room temperature photoluminescence and micro-photoluminescence are used to observe the optical properties of the atomic layer deposition (ALD) based ZnO NWs. The sharp UV luminescence observed from the ALD ZnO NWs is unexpected for the polycrystalline nanostructure. Surprisingly, the defect related luminescence is much decreased compared to an ALD ZnO film deposited at the same time ona plane substrate. Electrical characterization was carried out by using nanomanipulators. With the p-type Si substrate and the n-type ZnO NWs the nanodevices represent p–n NW diodes.The nanowire diodes show a very high breakthrough potential which implies that the ALD ZnO NWs can be used for future electronic applications.

  9. Using Computer-Assisted Argumentation Mapping to develop effective argumentation skills in high school advanced placement physics

    NASA Astrophysics Data System (ADS)

    Heglund, Brian

    Educators recognize the importance of reasoning ability for development of critical thinking skills, conceptual change, metacognition, and participation in 21st century society. There is a recognized need for students to improve their skills of argumentation, however, argumentation is not explicitly taught outside logic and philosophy---subjects that are not part of the K-12 curriculum. One potential way of supporting the development of argumentation skills in the K-12 context is through incorporating Computer-Assisted Argument Mapping to evaluate arguments. This quasi-experimental study tested the effects of such argument mapping software and was informed by the following two research questions: 1. To what extent does the collaborative use of Computer-Assisted Argumentation Mapping to evaluate competing theories influence the critical thinking skill of argument evaluation, metacognitive awareness, and conceptual knowledge acquisition in high school Advanced Placement physics, compared to the more traditional method of text tables that does not employ Computer-Assisted Argumentation Mapping? 2. What are the student perceptions of the pros and cons of argument evaluation in the high school Advanced Placement physics environment? This study examined changes in critical thinking skills, including argumentation evaluation skills, as well as metacognitive awareness and conceptual knowledge, in two groups: a treatment group using Computer-Assisted Argumentation Mapping to evaluate physics arguments, and a comparison group using text tables to evaluate physics arguments. Quantitative and qualitative methods for collecting and analyzing data were used to answer the research questions. Quantitative data indicated no significant difference between the experimental groups, and qualitative data suggested students perceived pros and cons of argument evaluation in the high school Advanced Placement physics environment, such as self-reported sense of improvement in argument

  10. Engineering design and analysis of advanced physical fine coal cleaning technologies. Quarterly technical progress report No. 9, October--December 1991

    SciTech Connect

    Not Available

    1992-01-20

    This project is sponsored by the United States Department of Energy (DOE) for the ``Engineering Design and Analysis of Advanced Physical Fine Coal Cleaning Technologies. The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies-heavy-liquid cylconing, selective agglomeration, and advanced froth flotation through the proof-of-concept (POC) level.

  11. Advanced computations of multi-physics, multi-scale effects in beam dynamics

    SciTech Connect

    Amundson, J.F.; Macridin, A.; Spentzouris, P.; Stern, E.G.; /Fermilab

    2009-01-01

    Current state-of-the-art beam dynamics simulations include multiple physical effects and multiple physical length and/or time scales. We present recent developments in Synergia2, an accelerator modeling framework designed for multi-physics, multi-scale simulations. We summarize recent several recent results in multi-physics beam dynamics, including simulations of three Fermilab accelerators: the Tevatron, the Main Injector and the Debuncher. Early accelerator simulations focused on single-particle dynamics. To a first approximation, the forces on the particles in an accelerator beam are dominated by the external fields due to magnets, RF cavities, etc., so the single-particle dynamics are the leading physical effects. Detailed simulations of accelerators must include collective effects such as the space-charge repulsion of the beam particles, the effects of wake fields in the beam pipe walls and beam-beam interactions in colliders. These simulations require the sort of massively parallel computers that have only become available in recent times. We give an overview of the accelerator framework Synergia2, which was designed to take advantage of the capabilities of modern computational resources and enable simulations of multiple physical effects. We also summarize some recent results utilizing Synergia2 and BeamBeam3d, a tool specialized for beam-beam simulations.

  12. Physics Comes to Winnipeg: The 1909 Meeting of the British Association for the Advancement of Science

    ERIC Educational Resources Information Center

    Klassen, Stephen; Dietrich, Sarah

    2010-01-01

    History of science can be used to bring scientific concepts to school science in a way that humanizes the protagonists and provides an appropriate context. The authors have researched the 1909 meeting of the British Association for the Advancement of Science (BAAS) in Winnipeg, a significant event in the city's history that has remained largely…

  13. U.S. Poised to Sit Out TIMSS Test: Physics, Advanced Math Gauged in Global Study

    ERIC Educational Resources Information Center

    Viadero, Debra

    2007-01-01

    This article reports on reactions to the U.S. Department of Education's first time decision to sit out an international study designed to show how advanced high school students around the world measure up in math and science. Mark S. Schneider, the commissioner of the department's National Center for Education Statistics, which normally takes the…

  14. Performance in Physical Science Education by Dint of Advance Organiser Model of Teaching

    ERIC Educational Resources Information Center

    Bency, P. B. Beulahbel; Raja, B. William Dharma

    2010-01-01

    Education should be made painless and the teaching must be made effective. Teaching is an activity, which is designed and performed for multiple objectives, in terms of changes in student behaviours. Models of teaching are just a blue print designed in advance for providing necessary structure and direction to the teacher for realizing the…

  15. Engineering development of advanced physical fine coal cleaning for premium fuel applications

    SciTech Connect

    Smit, F.J.; Jha, M.C.

    1993-01-18

    This project is a step in the Department of Energy's program to show that ultra-clean fuel can be produced from selected coals and that the fuel will be a cost-effective replacement for oil and natural gas now fueling boilers in this country. The replacement of premium fossil fuels with coal can only be realized if retrofit costs are kept to a minimum and retrofit boiler emissions meet national goals for clean air. These concerns establish the specifications for maximum ash and sulfur levels and combustion properties of the ultra-clean coal. The primary objective is to develop the design base for prototype commercial advanced fine coal cleaning facilities capable of producing ultra-clean coals suitable for conversion to coal-water slurry fuel. The fine coal cleaning technologies are advanced column flotation and selective agglomeration. A secondary objective is to develop the design base for near-term commercial integration of advanced fine coal cleaning technologies in new or existing coal preparation plants for economically and efficiently processing minus 28-mesh coal fines. A third objective is to determine the distribution of toxic trace elements between clean coal and refuse when applying the advance column flotation and selective agglomeration technologies. The project team consists of Amax Research Development Center (Amax R D), Amax Coal industries, Bechtel Corporation, Center for Applied Energy Research (CAER) at the University of Kentucky, and Arcanum Corporation.

  16. Engineering design and analysis of advanced physical fine coal cleaning technologies

    SciTech Connect

    Gallier, P.W.

    1991-10-20

    The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies- heavy-liquid cylconing, selective agglomeration, and advanced froth flotation through the proof-of- concept (POC) level. The commercially available ASPEN PLUS process simulation package will be extended to handle coal applications. Algorithms for predicting the process performance, equipment size, and flowsheet economics of commercial coal cleaning devices and related ancillary equipment will be incorporated into the coal cleaning simulator. This report is submitted to document the progress of Aspen Technology, Inc. (ApsenTech), its contractor, ICF Kaiser Engineers, Inc., (ICF KE) and CQ Inc., a subcontractor to ICF KE, for the seventh quarterly reporting period, April through June 1991. ICF KE is providing coal preparation consulting and processing engineering services in this work and they are responsible for recommending the design of models to represent conventional coal cleaning equipment and costing of these models.

  17. Engineering design and analysis of advanced physical fine coal cleaning technologies

    SciTech Connect

    Gallier, P.W.

    1990-10-20

    The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies-heavy-liquid cycloning, selective agglomeration, and advanced froth flotation through the proof-of-concept (POC) level. The ASPEN PLUS process simulation package will be extended to handle coal cleaning applications. Algorithms for predicting the process performance, equipment size, and flowsheet economics of commercial coal cleaning devices and related ancillary equipment will be incorporated into the coal cleaning simulator. The work plan for the froth quarter called for completion of the washability interpolation routine, gravity separation models, and dewatering models. As these items were completed, work in the areas of size reduction, classification and froth flotation were scheduled to begin. As each model was completed, testing and validation procedures were scheduled to begin. Costing models were also planned to be implemented and tested as each of the gravity separation models were completed. 1 tab.

  18. 2004 Rahman Prize in Computational Physics: HOW DO SOLIDS FAIL? A Research Adventure Using Lots Of Atoms And Big Computers

    NASA Astrophysics Data System (ADS)

    Abraham, Farid

    2004-03-01

    During the last decade, I have been simulating the dynamic failure of brittle and ductile solids at the atomic level using millions of atoms and some of the world's fastest computers. Computer experiments encompassing crack dynamics in brittle fracture, crack blunting in ductile failure, and dislocation entanglement in work-hardening are some examples and have given new and exciting insights into the failure processes of solids. My goal is to give the audience an appreciation for the power of atomistic simulations, coupled with visualization, in studying "how solids fail."

  19. Advances in the helium-jet coupled on-line mass separator RAMA. [Recoil Atom Mass Analyzer

    SciTech Connect

    Moltz, D M; Aysto, J; Cable, M D; Parry, R F; Haustein, P E; Wouters, J M; Cerny, J

    1980-01-01

    General improvements to the on-line mass separator RAMA (Recoil Atom Mass Analyzer) have yielded a greater reliability and efficiency for some elements. A new utilitarian helium-jet chamber has been installed to facilitate quick target and degrader foil changes in addition to a new ion source holder. A higher efficiency hollow-cathode, cathode-extraction ion source, for lower melting point elements (< 1200/sup 0/C) has also been designed. Tests with the beta-delayed proton emitter /sup 37/Ca showed a factor of five increase in yield over the old hollow-cathode, anode-extraction source. A differentially-pumped-tape drive system compatible with both ..gamma..-..gamma.. and ..beta..-..gamma.. experiments has been incorporated into the general detection system. All major operating parameters will soon be monitored by a complete stand-alone microprocessor system which will eventually be upgraded to a closed-loop control system.

  20. Interest and preferences for using advanced physical activity tracking devices: results of a national cross-sectional survey

    PubMed Central

    Alley, Stephanie; Schoeppe, Stephanie; Guertler, Diana; Jennings, Cally; Vandelanotte, Corneel

    2016-01-01

    Objectives Pedometers are an effective self-monitoring tool to increase users' physical activity. However, a range of advanced trackers that measure physical activity 24 hours per day have emerged (eg, Fitbit). The current study aims to determine people's current use, interest and preferences for advanced trackers. Design and participants A cross-sectional national telephone survey was conducted in Australia with 1349 respondents. Outcome measures Regression analyses were used to determine whether tracker interest and use, and use of advanced trackers over pedometers is a function of demographics. Preferences for tracker features and reasons for not wanting to wear a tracker are also presented. Results Over one-third of participants (35%) had used a tracker, and 16% are interested in using one. Multinomial regression (n=1257) revealed that the use of trackers was lower in males (OR=0.48, 95% CI 0.36 to 0.65), non-working participants (OR=0.43, 95% CI 0.30 to 0.61), participants with lower education (OR=0.52, 95% CI 0.38 to 0.72) and inactive participants (OR=0.52, 95% CI 0.39 to 0.70). Interest in using a tracker was higher in younger participants (OR=1.73, 95% CI 1.15 to 2.58). The most frequently used tracker was a pedometer (59%). Logistic regression (n=445) revealed that use of advanced trackers compared with pedometers was higher in males (OR=1.67, 95% CI 1.01 to 2.79) and younger participants (OR=2.96, 95% CI 1.71 to 5.13), and lower in inactive participants (OR=0.35, 95% CI 0.19 to 0.63). Over half of current or interested tracker users (53%) prefer to wear it on their wrist, 31% considered counting steps the most important function and 30% regarded accuracy as the most important characteristic. The main reasons for not wanting to use a tracker were, ‘I don't think it would help me’ (39%), and ‘I don't want to increase my activity’ (47%). Conclusions Activity trackers are a promising tool to engage people in self-monitoring a physical activity

  1. Improved Simulations of Astrophysical Plasmas: Computation of New Atomic Data

    NASA Technical Reports Server (NTRS)

    Gorczyca, Thomas W.; Korista, Kirk T.

    2005-01-01

    Our research program is designed to carry out state-of-the-art atomic physics calculations crucial to advancing our understanding of fundamental astrophysical problems. We redress the present inadequacies in the atomic data base along two important areas: dielectronic recombination and inner-shell photoionization and multiple electron ejection/Auger fluorescence therefrom. All of these data are disseminated to the astrophysical community in the proper format for implementation in spectral simulation code.

  2. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    SciTech Connect

    Not Available

    1992-01-01

    In order to develop additional confidence in the conceptual design of the advanced froth flotation circuit, a 2-3 TPH Proof-of-Concept (POC) facility was necessary. During operation of this facility, the ICF KE team will demonstrate the ability of the conceptual flowsheets to meet the program goals of maximum pyritic sulfur reduction coupled with maximum energy recovery on three DOE specified coals. The POC circuit was designed to be integrated into the Ohio Coal Development's facility near Beverly, Ohio. OCDO's facility will provide the precleaning unit operations and ICF KE will add the advanced froth flotation circuitry. The work in this task will include the POC conceptual design, flowsheet development, equipment list, fabrication and construction drawings, procurement specifications and bid packages and a facilities.

  3. Fuels for Advanced Combustion Engines Research Diesel Fuels: Analysis of Physical and Chemical Properties

    SciTech Connect

    Gallant, Tom; Franz, Jim; Alnajjar, Mikhail; Storey, John Morse; Lewis Sr, Samuel Arthur; Sluder, Scott; Cannella, William C; Fairbridge, Craig; Hager, Darcy; Dettman, Heather; Luecke, Jon; Ratcliff, Matthew A.; Zigler, Brad

    2009-01-01

    The CRC Fuels for Advanced Combustion Engines working group has worked to identify a matrix of research diesel fuels for use in advanced combustion research applications. Nine fuels were specified and formulated to investigate the effects of cetane number aromatic content and 90% distillation fraction. Standard ASTM analyses were performed on the fuels as well as GC/MS and /u1H//u1/u3C NMR analyses and thermodynamic characterizations. Details of the actual results of the fuel formulations compared with the design values are presented, as well as results from standard analyses, such as heating value, viscosity and density. Cetane number characterizations were accomplished by using both the engine method and the Ignition Quality Tester (IQT/sT) apparatus.

  4. Specification of the Advanced Burner Test Reactor Multi-Physics Coupling Demonstration Problem

    SciTech Connect

    Shemon, E. R.; Grudzinski, J. J.; Lee, C. H.; Thomas, J. W.; Yu, Y. Q.

    2015-12-21

    This document specifies the multi-physics nuclear reactor demonstration problem using the SHARP software package developed by NEAMS. The SHARP toolset simulates the key coupled physics phenomena inside a nuclear reactor. The PROTEUS neutronics code models the neutron transport within the system, the Nek5000 computational fluid dynamics code models the fluid flow and heat transfer, and the DIABLO structural mechanics code models structural and mechanical deformation. The three codes are coupled to the MOAB mesh framework which allows feedback from neutronics, fluid mechanics, and mechanical deformation in a compatible format.

  5. Advanced Magnetic Resonance Imaging of the Physical Processes in Human Glioblastoma

    PubMed Central

    Emblem, Kyrre E.; Andronesi, Ovidiu; Rosen, Bruce

    2014-01-01

    The most common malignant primary brain tumor, glioblastoma (GBM) is a devastating disease with a grim prognosis. Patient survival is typically less than 2 years and fewer than 10% of patients survive more than 5 years. Magnetic Resonance Imaging (MRI) can have great utility in the diagnosis, grading and management of patients with GBM as many of the physical manifestations of the pathological processes in GBM can be visualized and quantified using MRI. Newer MRI techniques such as dynamic contrast enhanced (DCE) and dynamic susceptibility contrast (DSC) MRI provide functional information regarding the tumor hemodynamic status. Diffusion MRI can shed light on tumor cellularity and the disruption of white matter tracts in the proximity of tumors. MR spectroscopy can be used to study new tumor tissue markers such as IDH mutations. MRI is helping to noninvasively explore the link between the molecular basis of gliomas and the imaging characteristics of their physical processes. We will review several approaches to MR-based imaging and discuss the potential for these techniques to quantify the physical processes in glioblastoma including tumor cellularity and vascularity, metabolite expression, and patterns of tumor growth and recurrence. We will conclude with challenges and opportunities for further research in applying physical principles to better understand the biological process in this deadly disease. PMID:25183787

  6. Physical and Chemical Properties of the Copper-Alanine System: An Advanced Laboratory Project

    ERIC Educational Resources Information Center

    Farrell, John J.

    1977-01-01

    An integrated physical-analytical-inorganic chemistry laboratory procedure for use with undergraduate biology majors is described. The procedure requires five to six laboratory periods and includes acid-base standardizations, potentiometric determinations, computer usage, spectrophotometric determinations of crystal-field splitting…

  7. The Atomic Intrinsic Integration Approach: A Structured Methodology for the Design of Games for the Conceptual Understanding of Physics

    ERIC Educational Resources Information Center

    Echeverria, Alejandro; Barrios, Enrique; Nussbaum, Miguel; Amestica, Matias; Leclerc, Sandra

    2012-01-01

    Computer simulations combined with games have been successfully used to teach conceptual physics. However, there is no clear methodology for guiding the design of these types of games. To remedy this, we propose a structured methodology for the design of conceptual physics games that explicitly integrates the principles of the intrinsic…

  8. News UK public libraries offer walk-in access to research Atoms for Peace? The Atomic Weapons Establishment and UK universities Students present their research to academics: CERN@school Science in a suitcase: Marvin and Milo visit Ethiopia Inspiring telescopes A day for everyone teaching physics 2014 Forthcoming Events

    NASA Astrophysics Data System (ADS)

    2014-05-01

    UK public libraries offer walk-in access to research Atoms for Peace? The Atomic Weapons Establishment and UK universities Students present their research to academics: CERN@school Science in a suitcase: Marvin and Milo visit Ethiopia Inspiring telescopes A day for everyone teaching physics 2014 Forthcoming Events

  9. Coal surface control for advanced physical fine coal cleaning technologies. Final report, September 19, 1988--August 31, 1992

    SciTech Connect

    Morsi, B.I.; Chiang, S.H.; Sharkey, A.; Blachere, J.; Klinzing, G.; Araujo, G.; Cheng, Y.S.; Gray, R.; Streeter, R.; Bi, H.; Campbell, P.; Chiarlli, P.; Ciocco, M.; Hittle, L.; Kim, S.; Kim, Y.; Perez, L.; Venkatadri, R.

    1992-12-31

    This final report presents the research work carried out on the Coal Surface Control for Advanced Physical Fine Coal Cleaning Technologies project, sponsored by the US Department of Energy, Pittsburgh Energy Technology Center (DOE/PETC). The project was to support the engineering development of the selective agglomeration technology in order to reduce the sulfur content of US coals for controlling SO{sub 2} emissions (i.e., acid rain precursors). The overall effort was a part of the DOE/PETCs Acid Rain Control Initiative (ARCI). The overall objective of the project is to develop techniques for coal surface control prior to the advanced physical fine coal cleaning process of selective agglomeration in order to achieve 85% pyrite sulfur rejection at an energy recovery greater than 85% based on run-of-mine coal. The surface control is meant to encompass surface modification during grinding and laboratory beneficiation testing. The project includes the following tasks: Project planning; methods for analysis of samples; development of standard beneficiation test; grinding studies; modification of particle surface; and exploratory R&D and support. The coal samples used in this project include three base coals, Upper Freeport - Indiana County, PA, Pittsburgh NO. 8 - Belmont County, OH, and Illinois No. 6 - Randolph County, IL, and three additional coals, Upper Freeport - Grant County- WV, Kentucky No. 9 Hopkins County, KY, and Wyodak - Campbell County, WY. A total of 149 drums of coal were received.

  10. Coherent Atom Optics with Optical Potentials: A Summary of New Phenomena with Bose-Einstein Condensates at the University of Arizona

    DTIC Science & Technology

    2009-10-08

    BEC physics. First, we devel- oped techniques necessary to experimentally investigate dynamic quasi-condensed states. With our system, we have...the University of Arizona is the development of advanced atom-optical techniques for optically manipulating Bose-Einstein condensates (BECs). Our...further advance the field of atom optics via the exploration of new experimental atom-optical techniques and matter-wave mode control, as well as

  11. Flawed Nuclear Physics and Atomic Intelligence in the Campaign to deny Norwegian Heavy Water to Germany, 1942-1944

    NASA Astrophysics Data System (ADS)

    Børresen, Hans Christofer

    2012-12-01

    The military campaign to deny Norwegian heavy water to Germany in World War II did not diminish as the threat posed by heavy water in German hands dwindled, mainly because of excessive security among the Allies. Signs that Albert Speer (1905-1981) had decided in 1942 to stop the German atomic-bomb project were kept secret and ignored. Prominent Allied advisers like Leif Tronstad (1903-1945) and even Niels Bohr (1885-1962) were not told about the plutonium path to a German atomic bomb. Physicists did not brief advisers, decision makers, and Allied officers on how many years Werner Heisenberg (1901-1976) would need to accumulate enough heavy water (deuterium oxide, D2O) for an Uranmachine and then to extract and process plutonium for an atomic bomb. Had the flow of information been better, the military raids on the Norwegian heavy-water plant at Vemork could have been timed better, and the more costly of them could have been averted altogether.

  12. Greek Atomic Theory.

    ERIC Educational Resources Information Center

    Roller, Duane H. D.

    1981-01-01

    Focusing on history of physics, which began about 600 B.C. with the Ionian Greeks and reaching full development within three centuries, suggests that the creation of the concept of the atom is understandable within the context of Greek physical theory; so is the rejection of the atomic theory by the Greek physicists. (Author/SK)

  13. Chemistry and physics of a single atomic layer: strategies and challenges for functionalization of graphene and graphene-based materials.

    PubMed

    Yan, Liang; Zheng, Yue Bing; Zhao, Feng; Li, Shoujian; Gao, Xingfa; Xu, Bingqian; Weiss, Paul S; Zhao, Yuliang

    2012-01-07

    Graphene has attracted great interest for its superior physical, chemical, mechanical, and electrical properties that enable a wide range of applications from electronics to nanoelectromechanical systems. Functionalization is among the significant vectors that drive graphene towards technological applications. While the physical properties of graphene have been at the center of attention, we still lack the knowledge framework for targeted graphene functionalization. In this critical review, we describe some of the important chemical and physical processes for graphene functionalization. We also identify six major challenges in graphene research and give perspectives and practical strategies for both fundamental studies and applications of graphene (315 references).

  14. Advancing Minorities and Women to the PhD in Physics and Astronomy

    NASA Astrophysics Data System (ADS)

    Stassun, Keivan

    2017-01-01

    We briefly review the current status of underrepresented minorities in physics and astronomy: The underrepresentation of Black-, Hispanic-, and Native-Americans is an order of magnitude problem. We then describe the Fisk-Vanderbilt Masters-to-PhD Bridge program as a successful model for addressing this problem. Since 2004 the program has admitted 110 students, 90% of them underrepresented minorities (50% female), with a retention rate of 90%. The program has become the top producer of African American master's degrees in physics, and is now one of the top producers of minority PhDs in astronomy, materials science, and physics. We summarize the main features of the program including its core strategies: (1) replacing the GRE in admissions with indicators that are better predictive of long-term success, (2) partnering with a minority-serving institution for student training through collaborative research, and (3) using the master's degree as a deliberate stepping stone to the PhD. We show how misuse of the GRE in graduate admissions may by itself in large part explain the ongoing underrepresentation of minorities in PhD programs, and we describe our alternate methods to identify talented individuals most likely to succeed. We describe our mentoring model and toolkit which may be utilized to enhance the success of all PhD students.

  15. Power and promise of narrative for advancing physical therapist education and practice.

    PubMed

    Greenfield, Bruce H; Jensen, Gail M; Delany, Clare M; Mostrom, Elizabeth; Knab, Mary; Jampel, Ann

    2015-06-01

    This perspective article provides a justification for and an overview of the use of narrative as a pedagogical tool for educators to help physical therapist students, residents, and clinicians develop skills of reflection and reflexivity in clinical practice. The use of narratives is a pedagogical approach that provides a reflective and interpretive framework for analyzing and making sense of texts, stories, and other experiences within learning environments. This article describes reflection as a well-established method to support critical analysis of clinical experiences; to assist in uncovering different perspectives of patients, families, and health care professionals involved in patient care; and to broaden the epistemological basis (ie, sources of knowledge) for clinical practice. The article begins by examining how phronetic (ie, practical and contextual) knowledge and ethical knowledge are used in physical therapy to contribute to evidence-based practice. Narrative is explored as a source of phronetic and ethical knowledge that is complementary but irreducible to traditional objective and empirical knowledge-the type of clinical knowledge that forms the basis of scientific training. The central premise is that writing narratives is a cognitive skill that should be learned and practiced to develop critical reflection for expert practice. The article weaves theory with practical application and strategies to foster narrative in education and practice. The final section of the article describes the authors' experiences with examples of integrating the tools of narrative into an educational program, into physical therapist residency programs, and into a clinical practice.

  16. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    SciTech Connect

    Not Available

    1990-01-01

    An engineering development project was prepared to build upon the basic research effort conducted under a solicitation for research into Fine Coal Surface Control. The engineering development project is intended to use general plant design knowledge and conceptualize a plant to utilize advanced froth flotation technology to process coal and produce a product having maximum practical pyritic sulfur reduction consistent with maximum practical BTU recovery. This is being accomplished by utilization the basic research data on the surface properties of coal, mineral matter and pyrite obtained from the Coal Surface Control for Advanced Fine Coal Flotation Project, to develop this conceptual flowsheet. The conceptual flowsheet must be examined to identify critical areas that need additional design data. This data will then be developed using batch and semi-continuous bench scale testing. In addition to actual bench scale testing other unit operations from other industries processing fine material will be reviewed for potential application and incorporated into the design if appropriate. 31 figs., 22 tabs.

  17. PREFACE: International Conference on Advancement in Science and Technology 2012 (iCAST): Contemporary Mathematics, Mathematical Physics and their Applications

    NASA Astrophysics Data System (ADS)

    Ganikhodjaev, Nasir; Mukhamedov, Farrukh; Hee, Pah Chin

    2013-04-01

    The 4th International Conference on the Advancement of Science and Technology 2012 (iCAST 2012), with theme 'Contemporary Mathematics, Mathematical Physics and their Applications', took place in Kuantan, Malaysia, from Wednesday 7 to Friday 9 November 2012. The conference was attended by more than 100 participants, and hosted about 160 oral and poster papers by more than 140 pre-registered authors. The key topics of the 4th iCAST 2012 include Pure Mathematics, Applied Mathematics, Theoretical/Mathematical Physics, Dynamical Systems, Statistics and Financial Mathematics. The scientific program was rather full since after the Keynote and Invited Talks in the morning, four parallel sessions ran every day. However, according to all attendees, the program was excellent with a high level of talks and the scientific environment was fruitful; thus all attendees had a creative time. The conference aimed to promote the knowledge and development of high-quality research in mathematical fields concerned with the application of other scientific fields as well as modern technological trends in physics, chemistry, biology, medicine, economics, sociology and environmental sciences. We would like to thank the Keynote and the Invited Speakers for their significant contributions to 4th iCAST 2012. We would also like to thank the members of the International Scientific Committee and the members of the Organizing Committee. We cannot end without expressing our many thanks to International Islamic University Malaysia and our sponsors for their financial support . This volume presents selected papers which have been peer-reviewed. The editors hope that it may be useful and fruitful for scholars, researchers, and advanced technical members of the industrial laboratory facilities for developing new tools and products. Guest Editors Nasir Ganikhodjaev, Farrukh Mukhamedov and Pah Chin Hee The PDF contains the committee lists, board list and biographies of the plenary speakers.

  18. Brachytherapy boost in loco-regionally advanced nasopharyngeal carcinoma: a prospective randomized trial of the International Atomic Energy Agency

    PubMed Central

    2014-01-01

    Abstact Background The purpose was to determine whether a brachytherapy boost improves outcomes in patients with advanced nasopharyngeal carcinoma treated with standard chemo-radiotherapy. Methods Patients with nasopharyngeal carcinoma WHO grades I-III and TNM stages III or non-metastatic stage IV were eligible for this phase III study. Patients were randomized to either arm (A) induction chemotherapy, followed by external beam radiotherapy (EBRT) with concomitant cisplatin (n = 139) or arm (B), the same schedule plus a brachytherapy boost to the nasopharynx (n = 135). The EBRT doses given were 70 Gy to the primary tumour and positive lymph nodes and 46 Gy to the negative neck. The additional brachytherapy boost in arm (B) was given by either low dose-rate (LDR – 11 Gy) or high dose-rate (HDR – 3 fractions of 3.0 Gy) brachytherapy. The primary endpoint was 3-year overall survival (OS) and secondary endpoints were: local control, regional control, distant metastasis and grade 3–4 adverse events. Results 274 patients were randomized between September 2004 and December 2008. The two arms were comparable with regard to age, gender, stage and grade. 273 patients completed treatment. Median follow-up was 29 months (0.2-67 months). The effect of treatment arm, country, age, gender, WHO pathology, stage (T3-4, N2-3 versus other) and chemotherapy on overall survival (OS), disease-free survival (DFS) and local recurrence-free survival (LRFS) was studied. Stage significantly affected OS (p = 0.024) and DFS (p = 0.018) while age significantly affected OS (p = 0.014). None of the other factors studied were significant. The 3-year LRFS was 60.5% and 54.4% in arms A and B respectively (p = 0.647). The 3-year regional control rate in the neck was 59.7% and 54.3% respectively (p = 0.7). Distant metastasis developed in 59.7% of patients in arm A and 55.4% in arm B (p = 0.377). Patients with T1/T2 N + had a 3 year LRFS of 51.8% in Arm A (62 patients) versus 57.9% in Arm B (67

  19. 13th International Workshop on Advanced Computing and Analysis Techniques in Physics Research

    NASA Astrophysics Data System (ADS)

    Speer, T.; Boudjema, F.; Lauret, J.; Naumann, A.; Teodorescu, L.; Uwer, P.

    "Beyond the Cutting edge in Computing" Fundamental research is dealing, by definition, with the two extremes: the extremely small and the extremely large. The LHC and Astroparticle physics experiments will soon offer new glimpses beyond the current frontiers. And the computing infrastructure to support such physics research needs to look beyond the cutting edge. Once more it seems that we are on the edge of a computing revolution. But perhaps what we are seeing now is a even more epochal change where not only the pace of the revolution is changing, but also its very nature. Change is not any more an "event" meant to open new possibilities that have to be understood first and exploited then to prepare the ground for a new leap. Change is becoming the very essence of the computing reality, sustained by a continuous flow of technical and paradigmatic innovation. The hardware is definitely moving toward more massive parallelism, in a breathtaking synthesis of all the past techniques of concurrent computation. New many-core machines offer opportunities for all sorts of Single/Multiple Instructions, Single/Multiple Data and Vector computations that in the past required specialised hardware. At the same time, all levels of virtualisation imagined till now seem to be possible via Clouds, and possibly many more. Information Technology has been the working backbone of the Global Village, and now, in more than one sense, it is becoming itself the Global Village. Between these two, the gap between the need for adapting applications to exploit the new hardware possibilities and the push toward virtualisation of resources is widening, creating more challenges as technical and intellectual progress continues. ACAT 2010 proposes to explore and confront the different boundaries of the evolution of computing, and its possible consequences on our scientific activity. What do these new technologies entail for physics research? How will physics research benefit from this revolution in

  20. Engineering development of advanced physical fine coal cleaning technologies - froth flotation

    SciTech Connect

    Ferris, D.D.; Bencho, J.R.

    1995-11-01

    In 1988, ICF Kaiser Engineers was awarded DOE Contract No. DE-AC22-88PC88881 to research, develop, engineer and design a commercially acceptable advanced froth flotation coal cleaning technology. The DOE initiative is in support of the continued utilization of our most abundant energy resource. Besides the goal of commercialability, coal cleaning performance and product quality goals were established by the DOE for this and similar projects. primary among these were the goals of 85 percent energy recovery and 85 percent pyrite rejection. Three nationally important coal resources were used for this project: the Pittsburgh No. 8 coal, the Upper Freeport coal, and the Illinois No. 6 coal. Following is a summary of the key findings of this project.

  1. X-ray sources such as metallic liner inside plastic cavities are used to test atomic physics models for LMJ simulations

    NASA Astrophysics Data System (ADS)

    Girard, Frederic; Jacquet, L.; Primout, M.; Babonneau, D.; Villette, B.; Stemmler, Ph.

    2009-11-01

    Bright multi-keV K-shell emission sources [1-3] are necessary for ICF studies such as radiography of dense materials. Our recent works with titanium (Heα at 4.7 keV) and germanium (Heα at 10.3 keV) lined cavities showed very high multi-keV x-ray conversion efficiencies up to 14.0% and 0.8% (respectively) [3]. Cavities with a titanium, copper or germanium liner have been used on the OMEGA laser facility in Rochester to test specifically atomic physics models coupled to hydrodynamic codes. Simulation results differ significantly from experimental conversion efficiencies for titanium liner but they are close together for germanium one. Atomic physics models do have great impact on X-ray output. The need for accurate predictive simulation is important in order to set up relevant radiography sources for experiments on the path to ignition. Multi-keV emission is diagnosed by a full set of diagnostics giving conversion efficiencies, time dependant x-ray power and imaging, time integrated imaging and high resolution spectra of titanium. [4pt] [1] D. Babonneau et al., Phys. Plasmas, 15, 092702, 2008 [0pt] [2] K. B. Fournier et al., Phys. Plasmas, 16 052703, 2009 [0pt] [3] F. Girard et al., Phys. Plasmas, 16, 052704, 2009

  2. Human-centered design of a cyber-physical system for advanced response to Ebola (CARE).

    PubMed

    Dimitrov, Velin; Jagtap, Vinayak; Skorinko, Jeanine; Chernova, Sonia; Gennert, Michael; Padir, Taşkin

    2015-01-01

    We describe the process towards the design of a safe, reliable, and intuitive emergency treatment unit to facilitate a higher degree of safety and situational awareness for medical staff, leading to an increased level of patient care during an epidemic outbreak in an unprepared, underdeveloped, or disaster stricken area. We start with a human-centered design process to understand the design challenge of working with Ebola treatment units in Western Africa in the latest Ebola outbreak, and show preliminary work towards cyber-physical technologies applicable to potentially helping during the next outbreak.

  3. Integrated Physics Advances in Simulation of Wave Interactions with Extended MHD Phenomena

    SciTech Connect

    Batchelor, Donald B; D'Azevedo, Eduardo; Bateman, Glenn; Bernholdt, David E; Berry, Lee A; Bonoli, P.; Bramley, R; Breslau, J.; Chance, M.; Chen, J.; Choi, M.; Elwasif, Wael R; Fu, GuoYong; Harvey, R. W.; Houlberg, Wayne A; Jaeger, Erwin Frederick; Jardin, S. C.; Keyes, David E; Klasky, Scott A; Kruger, Scott; Ku, Long-Poe; McCune, Douglas; Schissel, D.; Schnack, D.; Wright, J. C.

    2007-06-01

    The broad scientific objectives of the SWIM (Simulation of Wave Interaction with MHD) project are: (A) To improve our understanding of interactions that both RF wave and particle sources have on extended-MHD phenomena, and to substantially improve our capability for predicting and optimizing the performance of burning plasmas in devices such as ITER: and (B) To develop an integrated computational system for treating multi-physics phenomena with the required flexibility and extensibility to serve as a prototype for the Fusion Simulation Project (FSP).

  4. Conditions for building a community of practice in an advanced physics laboratory

    NASA Astrophysics Data System (ADS)

    Irving, Paul W.; Sayre, Eleanor C.

    2014-06-01

    We use the theory of communities of practice and the concept of accountable disciplinary knowledge to describe how a learning community develops in the context of an upper-division physics laboratory course. The change in accountable disciplinary knowledge motivates students' enculturation into a community of practice. The enculturation process is facilitated by four specific structural features of the course and supported by a primary instructional choice. The four structural features are "paucity of instructor time," "all in a room together," "long and difficult experiments," and "same experiments at different times." The instructional choice is the encouragement of the sharing and development of knowledge and understanding by the instructor. The combination of the instructional choice and structural features promotes the development of the learning community in which students engage in authentic practices of a physicist. This results in a classroom community that can provide students with the opportunity to have an accelerated trajectory towards being a more central participant of the community of a practice of physicists. We support our claims with video-based observations of laboratory classroom interactions and individual, semistructured interviews with students about their laboratory experiences and physics identity.

  5. Physics.

    ERIC Educational Resources Information Center

    Bromley, D. Allan

    1980-01-01

    The author presents the argument that the past few years, in terms of new discoveries, insights, and questions raised, have been among the most productive in the history of physics. Selected for discussion are some of the most important new developments in physics research. (Author/SA)

  6. An analysis of predictors of enrollment and successful achievement for girls in high school Advanced Placement physics

    NASA Astrophysics Data System (ADS)

    Depalma, Darlene M.

    A problem within science education in the United States persists. U.S students rank lower in science than most other students from participating countries on international tests of achievement (National Center for Education Statistics, 2003). In addition, U.S. students overall enrollment rate in high school Advanced Placement (AP) physics is still low compared to other academic domains, especially for females. This problem is the background for the purpose of this study. This investigation examined cognitive and motivational variables thought to play a part in the under-representation of females in AP physics. Cognitive variables consisted of mathematics, reading, and science knowledge, as measured by scores on the 10th and 11th grade Florida Comprehensive Assessment Tests (FCAT). The motivational factors of attitude, stereotypical views toward science, self-efficacy, and epistemological beliefs were measured by a questionnaire developed with questions taken from previously proven reliable and valid instruments. A general survey regarding participation in extracurricular activities was also included. The sample included 12th grade students from two high schools located in Seminole County, Florida. Of the 106 participants, 20 girls and 27 boys were enrolled in AP physics, and 39 girls and 20 boys were enrolled in other elective science courses. Differences between males and females enrolled in AP physics were examined, as well as differences between females enrolled in AP physics and females that chose not to participate in AP physics, in order to determine predictors that apply exclusively to female enrollment in high school AP physics and predictors of an anticipated science related college major. Data were first analyzed by Exploratory Factor Analysis, followed by Analysis of Variance (ANOVA), independent t-tests, univariate analysis, and logistic regression analysis. One overall theme that emerged from this research was findings that refute the ideas that

  7. Miscibility studies of Polyethylene Glycol with Polystyrene in Toluene by Various Physical and Advanced Techniques

    NASA Astrophysics Data System (ADS)

    Padmanaban, R.; Venkatramanan, K.

    2016-10-01

    Polyethylene glycol (PEG) is a chemical that has an extensive variety of applications in the world of medicine. It is used as a base to manufacture certain medicines, assist in drug delivery, and is also used as an agent in some medical procedures. It is an osmotic laxative. Polyethylene glycol works by retaining water in the stool, resulting in softer stools and more frequent bowel movements. Polyethylene glycol does not affect glucose and electrolytes in the body. PEG refers to a hydrocarbon molecule that can have a variable size, and different sizes can have different physical properties, giving this compound a great deal of flexibility in its application. In the present study, Polyethylene Glycol (PEG) (Molar mass: 1500) is blended with Polystyrene (PS) (Molar mass: 35000) in Toluene. The miscibility nature of the poly blend is analyzed by Ultrasonic velocity, viscosity, density and refractive index techniques at 303K. The compatibility nature of the blend is confirmed by Differential Scanning Calorimetry (DSC) studies.

  8. The Frontier of Modern Calorimetry: Hardware Advances and Application in Particle Physics Analysis

    NASA Astrophysics Data System (ADS)

    Medvedeva, Tatiana

    While the last missing components of the SM puzzle seem to be successfully found, particle physicists remain hungry for what might be there, beyond the cosy boundaries of the well studies elementary particle world. However, the sophisticated technique of data analysis and acute Monte Carlo simulations remain fruitless. It appears that the successful intrusion into the realm, in which we were not welcome so far, may require a very different implication of effort. All those results might suggest, though banal, that we need an improvement on the hardware side. Indeed, the hadronic calorimeter of CMS is no competitor to its other state-of-art components. This obstacle in many cases significantly complicates the flow of the physics analysis. Besides, the era of high luminosity LHC operation in the offing is calling for the same. After exploration of the analysis debri with 8TeV collision data, we investigate various approaches for better calorimetry for the CMS detector.

  9. Advances in wearable technology and applications in physical medicine and rehabilitation.

    PubMed

    Bonato, Paolo

    2005-02-25

    The development of miniature sensors that can be unobtrusively attached to the body or can be part of clothing items, such as sensing elements embedded in the fabric of garments, have opened countless possibilities of monitoring patients in the field over extended periods of time. This is of particular relevance to the practice of physical medicine and rehabilitation. Wearable technology addresses a major question in the management of patients undergoing rehabilitation, i.e. have clinical interventions a significant impact on the real life of patients? Wearable technology allows clinicians to gather data where it matters the most to answer this question, i.e. the home and community settings. Direct observations concerning the impact of clinical interventions on mobility, level of independence, and quality of life can be performed by means of wearable systems. Researchers have focused on three main areas of work to develop tools of clinical interest: 1)the design and implementation of sensors that are minimally obtrusive and reliably record movement or physiological signals, 2)the development of systems that unobtrusively gather data from multiple wearable sensors and deliver this information to clinicians in the way that is most appropriate for each application, and 3)the design and implementation of algorithms to extract clinically relevant information from data recorded using wearable technology. Journal of NeuroEngineering and Rehabilitation has devoted a series of articles to this topic with the objective of offering a description of the state of the art in this research field and pointing to emerging applications that are relevant to the clinical practice in physical medicine and rehabilitation.

  10. Engineering development of advance physical fine coal cleaning for premium fuel applications

    SciTech Connect

    Jha, M.C.; Smit, F.J.; Shields, G.L.

    1995-11-01

    The objective of this project is to develop the engineering design base for prototype fine coal cleaning plants based on Advanced Column Flotation and Selective Agglomeration processes for premium fuel and near-term applications. Removal of toxic trace elements is also being investigated. The scope of the project includes laboratory research and bench-scale testing of each process on six coals followed by design, construction, and operation of a 2 tons/hour process development unit (PDU). Three coals will be cleaned in tonnage quantity and provided to DOE and its contractors for combustion evaluation. Amax R&D (now a subsidiary of Cyprus Amax Mineral Company) is the prime contractor. Entech Global is managing the project and performing most of the research and development work as an on-site subcontractor. Other participants in the project are Cyprus Amax Coal Company, Arcanum, Bechtel, TIC, University of Kentucky and Virginia Tech. Drs. Keller of Syracuse and Dooher of Adelphi University are consultants.

  11. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    SciTech Connect

    Not Available

    1991-01-01

    The design criteria for each unit operation have been developed based upon a number of variables. These variables, at this time, are based upon the best engineering design information available to industry. A number of assumptions utilized in the design criteria are uncertain. The uncertainties of inert atmospheres for grinding and flotation as well as pyrite depressants were answered by the Surface Control Project. It was determined that inerting was not required and no new'' reagents were presented that improved the flotation results. In addition, Tasks 5 and 6 results indicated the required reagent dosage for conventional flotation and advanced flotation. Task 5 results also indicated the need for a clean coal,thickener, the flocculent dosages for both the clean coal and refuse thickeners, and final dewatering requirements. The results from Tasks 5 and 6 and summarized in Task 7 indicate several uncertainties that require continuous long duration testing. The first is the possibility of producing a grab product for both the Pittsburgh and Illinois No. 6 coals in conventional flotation. Second what does long-term recirculation of clarified water do to the product quality The verification process and real data obtained from Tasks 5 and 6 greatly reduced the capital and operating costs for the process. This was anticipated and the test work indeed provided confirming data.

  12. Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications

    SciTech Connect

    Smit, Frank J; Schields, Gene L; Jha, Mehesh C; Moro, Nick

    1997-09-26

    The ash in six common bituminous coals, Taggart, Winifrede, Elkhorn No. 3, Indiana VII, Sunnyside and Hiawatha, could be liberated by fine grinding to allow preparation of clean coal meeting premium fuel specifications (< 1- 2 lb/ MBtu ash and <0.6 lb/ MBtu sulfur) by laboratory and bench- scale column flotation or selective agglomeration. Over 2,100 tons of coal were cleaned in the PDU at feed rates between 2,500 and 6,000 lb/ h by Microcel™ column flotation and by selective agglomeration using recycled heptane as the bridging liquid. Parametric testing of each process and 72- hr productions runs were completed on each of the three test coals. The following results were achieved after optimization of the operating parameters: The primary objective was to develop the design base for commercial fine coal cleaning facilities for producing ultra- clean coals which can be converted into coal-water slurry premium fuel. The coal cleaning technologies to be developed were advanced column flotation and selective agglomeration, and the goal was to produce fuel meeting the following specifications.

  13. Reactor Physics Scoping and Characterization Study on Implementation of TRIGA Fuel in the Advanced Test Reactor

    SciTech Connect

    Jennifer Lyons; Wade R. Marcum; Mark D. DeHart; Sean R. Morrell

    2014-01-01

    The Advanced Test Reactor (ATR), under the Reduced Enrichment for Research and Test Reactors (RERTR) Program and the Global Threat Reduction Initiative (GTRI), is conducting feasibility studies for the conversion of its fuel from a highly enriched uranium (HEU) composition to a low enriched uranium (LEU) composition. These studies have considered a wide variety of LEU plate-type fuels to replace the current HEU fuel. Continuing to investigate potential alternatives to the present HEU fuel form, this study presents a preliminary analysis of TRIGA® fuel within the current ATR fuel envelopes and compares it to the functional requirements delineated by the Naval Reactors Program, which includes: greater than 4.8E+14 fissions/s/g of 235U, a fast to thermal neutron flux ratio that is less than 5% deviation of its current value, a constant cycle power within the corner lobes, and an operational cycle length of 56 days at 120 MW. Other parameters outside those put forth by the Naval Reactors Program which are investigated herein include axial and radial power profiles, effective delayed neutron fraction, and mean neutron generation time.

  14. An atomic clock with 10(-18) instability.

    PubMed

    Hinkley, N; Sherman, J A; Phillips, N B; Schioppo, M; Lemke, N D; Beloy, K; Pizzocaro, M; Oates, C W; Ludlow, A D

    2013-09-13

    Atomic clocks have been instrumental in science and technology, leading to innovations such as global positioning, advanced communications, and tests of fundamental constant variation. Timekeeping precision at 1 part in 10(18) enables new timing applications in relativistic geodesy, enhanced Earth- and space-based navigation and telescopy, and new tests of physics beyond the standard model. Here, we describe the development and operation of two optical lattice clocks, both using spin-polarized, ultracold atomic ytterbium. A measurement comparing these systems demonstrates an unprecedented atomic clock instability of 1.6 × 10(-18) after only 7 hours of averaging.

  15. Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

    NASA Astrophysics Data System (ADS)

    Bonne, François; Alamir, Mazen; Bonnay, Patrick

    2014-01-01

    In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  16. Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

    SciTech Connect

    Bonne, François; Bonnay, Patrick

    2014-01-29

    In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  17. Physical/chemical properties of tin oxide thin film transistors prepared using plasma-enhanced atomic layer deposition

    SciTech Connect

    Lee, Byung Kook; Jung, Eunae; Kim, Seok Hwan; Moon, Dae Chul; Lee, Sun Sook; Park, Bo Keun; Hwang, Jin Ha; Chung, Taek-Mo; Kim, Chang Gyoun; An, Ki-Seok

    2012-10-15

    Thin film transistors (TFTs) with tin oxide films as the channel layer were fabricated by means of plasma enhanced atomic layer deposition (PE-ALD). The as-deposited tin oxide films show n-type conductivity and a nano-crystalline structure of SnO{sub 2}. Notwithstanding the relatively low deposition temperatures of 70, 100, and 130 °C, the bottom gate tin oxide TFTs show an on/off drain current ratio of 10{sup 6} while the device mobility values were increased from 2.31 cm{sup 2}/V s to 6.24 cm{sup 2}/V s upon increasing the deposition temperature of the tin oxide films.

  18. Physics Basis for the Advanced Tokamak Fusion Power Plant ARIES-AT

    SciTech Connect

    S.C. Jardin; C.E. Kessel; T.K. Mau; R.L. Miller; F. Najmabadi; V.S. Chan; M.S. Chu; R. LaHaye; L.L. Lao; T.W. Petrie; P. Politzer; H.E. St. John; P. Snyder; G.M. Staebler; A.D. Turnbull; W.P. West

    2003-10-07

    The advanced tokamak is considered as the basis for a fusion power plant. The ARIES-AT design has an aspect ratio of A always equal to R/a = 4.0, an elongation and triangularity of kappa = 2.20, delta = 0.90 (evaluated at the separatrix surface), a toroidal beta of beta = 9.1% (normalized to the vacuum toroidal field at the plasma center), which corresponds to a normalized beta of bN * 100 x b/(I(sub)P(MA)/a(m)B(T)) = 5.4. These beta values are chosen to be 10% below the ideal-MHD stability limit. The bootstrap-current fraction is fBS * I(sub)BS/I(sub)P = 0.91. This leads to a design with total plasma current I(sub)P = 12.8 MA, and toroidal field of 11.1 T (at the coil edge) and 5.8 T (at the plasma center). The major and minor radii are 5.2 and 1.3 m, respectively. The effects of H-mode edge gradients and the stability of this configuration to non-ideal modes is analyzed. The current-drive system consists of ICRF/FW for on-axis current drive and a lower-hybrid system for off-axis. Tran sport projections are presented using the drift-wave based GLF23 model. The approach to power and particle exhaust using both plasma core and scrape-off-layer radiation is presented.

  19. Physical and chemical effects of direct aqueous advanced oxidation processing on green sand foundry mold materials

    NASA Astrophysics Data System (ADS)

    Clobes, Jason Kenneth

    Iron foundries using the common green sand molding process have increasingly been incorporating aqueous advanced oxidation (AO) systems to reduce the consumption of sand system bentonite clay and coal raw materials by and to decrease their volatile organic compound (VOC) emissions. These AO systems typically use a combination of sonication, ozone aeration, and hydrogen peroxide to treat and recycle slurries of sand system baghouse dust, which is rich in clay and coal. While the overall effects of AO on raw material consumption and organic emissions are known, the mechanisms behind these effects are not well understood. This research examined the effects of bench-scale direct aqueous AO processing on green sand mold materials at the micro level. Bench-scale AO processing, including acoustic sonication, ozone/oxygen aeration, and hydrogen peroxide dramatically decreased the particle sizes of both western bentonite and foundry sand system baghouse dust. Bench-scale AO processing was shown to effectively separate the clay material from the larger silica and coal particles and to extensively break up the larger clay agglomerates. The acoustic sonication component of AO processing was the key contributor to enhanced clay recovery. Acoustic sonication alone was slightly more effective than combined component AO in reducing the particle sizes of the baghouse dust and in the recovery of clay yields in the supernatant during sedimentation experiments. Sedimentation separation results correlated well with the increase in small particle concentrations due to AO processing. Clay suspension viscosity decreased with AO processing due to enhanced dispersion of the particles. X-ray diffraction of freeze-dried baghouse dust indicated that AO processing does not rehydrate calcined montmorillonite and does not increase the level of interlayer water hydration in the dry clays. Zeta potential measurements indicated that AO processing also does not produce any large changes in the

  20. Advanced Materials From Fungal Mycelium: Fabrication and Tuning of Physical Properties

    PubMed Central

    Haneef, Muhammad; Ceseracciu, Luca; Canale, Claudio; Bayer, Ilker S.; Heredia-Guerrero, José A.; Athanassiou, Athanassia

    2017-01-01

    In this work is presented a new category of self-growing, fibrous, natural composite materials with controlled physical properties that can be produced in large quantities and over wide areas, based on mycelium, the main body of fungi. Mycelia from two types of edible, medicinal fungi, Ganoderma lucidum and Pleurotus ostreatus, have been carefully cultivated, being fed by two bio-substrates: cellulose and cellulose/potato-dextrose, the second being easier to digest by mycelium due to presence of simple sugars in its composition. After specific growing times the mycelia have been processed in order to cease their growth. Depending on their feeding substrate, the final fibrous structures showed different relative concentrations in polysaccharides, lipids, proteins and chitin. Such differences are reflected as alterations in morphology and mechanical properties. The materials grown on cellulose contained more chitin and showed higher Young’s modulus and lower elongation than those grown on dextrose-containing substrates, indicating that the mycelium materials get stiffer when their feeding substrate is harder to digest. All the developed fibrous materials were hydrophobic with water contact angles higher than 120°. The possibility of tailoring mycelium materials’ properties by properly choosing their nutrient substrates paves the way for their use in various scale applications. PMID:28117421

  1. Advanced Materials From Fungal Mycelium: Fabrication and Tuning of Physical Properties

    NASA Astrophysics Data System (ADS)

    Haneef, Muhammad; Ceseracciu, Luca; Canale, Claudio; Bayer, Ilker S.; Heredia-Guerrero, José A.; Athanassiou, Athanassia

    2017-01-01

    In this work is presented a new category of self-growing, fibrous, natural composite materials with controlled physical properties that can be produced in large quantities and over wide areas, based on mycelium, the main body of fungi. Mycelia from two types of edible, medicinal fungi, Ganoderma lucidum and Pleurotus ostreatus, have been carefully cultivated, being fed by two bio-substrates: cellulose and cellulose/potato-dextrose, the second being easier to digest by mycelium due to presence of simple sugars in its composition. After specific growing times the mycelia have been processed in order to cease their growth. Depending on their feeding substrate, the final fibrous structures showed different relative concentrations in polysaccharides, lipids, proteins and chitin. Such differences are reflected as alterations in morphology and mechanical properties. The materials grown on cellulose contained more chitin and showed higher Young’s modulus and lower elongation than those grown on dextrose-containing substrates, indicating that the mycelium materials get stiffer when their feeding substrate is harder to digest. All the developed fibrous materials were hydrophobic with water contact angles higher than 120°. The possibility of tailoring mycelium materials’ properties by properly choosing their nutrient substrates paves the way for their use in various scale applications.

  2. A Comprehensive Analysis of the Physical Properties of Advanced GaAs/AlGaAs Junctions

    NASA Technical Reports Server (NTRS)

    Menkara, Hicham M.

    1996-01-01

    Extensive studies have been performed on MQW junctions and structures because of their potential applications as avalanche photodetectors in optical communications and imaging systems. The role of the avalanche photodiode is to provide for the conversion of an optical signal into charge. Knowledge of junction physics, and the various carrier generation/recombination mechanisms, is crucial for effectively optimizing the conversion process and increasing the structure's quantum efficiency. In addition, the recent interest in the use of APDs in imaging systems has necessitated the development of semiconductor junctions with low dark currents and high gains for low light applications. Because of the high frame rate and high pixel density requirements in new imaging applications, it is necessary to provide some front-end gain in the imager to allow operation under reasonable light conditions. Understanding the electron/hole impact ionization process, as well as diffusion and surface leakage effects, is needed to help maintain low dark currents and high gains for such applications. In addition, the APD must be capable of operating with low power, and low noise. Knowledge of the effects of various doping configurations and electric field profiles, as well as the excess noise resulting from the avalanche process, are needed to help maintain low operating bias and minimize the noise output.

  3. Advanced Materials From Fungal Mycelium: Fabrication and Tuning of Physical Properties.

    PubMed

    Haneef, Muhammad; Ceseracciu, Luca; Canale, Claudio; Bayer, Ilker S; Heredia-Guerrero, Jose A; Athanassiou, Athanassia

    2017-01-24

    In this work is presented a new category of self-growing, fibrous, natural composite materials with controlled physical properties that can be produced in large quantities and over wide areas, based on mycelium, the main body of fungi. Mycelia from two types of edible, medicinal fungi, Ganoderma lucidum and Pleurotus ostreatus, have been carefully cultivated, being fed by two bio-substrates: cellulose and cellulose/potato-dextrose, the second being easier to digest by mycelium due to presence of simple sugars in its composition. After specific growing times the mycelia have been processed in order to cease their growth. Depending on their feeding substrate, the final fibrous structures showed different relative concentrations in polysaccharides, lipids, proteins and chitin. Such differences are reflected as alterations in morphology and mechanical properties. The materials grown on cellulose contained more chitin and showed higher Young's modulus and lower elongation than those grown on dextrose-containing substrates, indicating that the mycelium materials get stiffer when their feeding substrate is harder to digest. All the developed fibrous materials were hydrophobic with water contact angles higher than 120°. The possibility of tailoring mycelium materials' properties by properly choosing their nutrient substrates paves the way for their use in various scale applications.

  4. Four Reflector VUV Quarter-wave Retarder of the Beamline 10.0.2 of the Advanced Light Source to Study Angular Momentum Sharing in Atoms

    NASA Astrophysics Data System (ADS)

    Yenen, O.; Jaecks, D. H.; McLaughlin, K. W.; Snell, G.

    2000-06-01

    We have installed, calibrated and characterized a quarter-wave retarder to transform linearly polarized synchrotron radiation into circularly polarized radiation. The quarter-wave retarder based on earlier suggestions and prototypes is built at the Physical Sciences Laboratory, Stoughton WI. The retarder is optimized to obtain circularly polarized radiation in the 10-60 eV range. Using a 45 degree reflector gold mirror linear polarization analyzer, we have determined that the retarder produces better than 99.7 % circularly polarized radiation from the linearly polarized VUV radiation in the 35.5 to 37 eV photon energy range typically with 1 % transmission efficiency. The retarder is installed in the High Resolution AMO Beam Line 10.0.2 of the Advanced Light Source, Lawrence-Berkeley National Laboratory, Berkeley, CA. The circularly polarized photons produced by the retarder are used to study relativistic electron-electron interactions in photoionization.

  5. Pegram Nuclear Physics Laboratories Progress Report for January 1969 through December 1969 to the United States Atomic Energy Commission

    DTIC Science & Technology

    1969-12-01

    determined to afflict 0.03 to 0.13 percent of Americans - about 600,000 people. (2) Red blood cells containing a predominance of abnormal sickle cell ... cells causes symptons of anemia (reduced oxygen carrying capacity of the blood ), hemolysis (increased blood destruction), and thrombosis (obstruction of...death often result from clogging of small capillaries by the elongated red blood IC. G. Jacobs et al., Physics Letters 29A, 498 (1969). 2A. Cantarow and

  6. Advances in the physics understanding of ELM suppression using resonant magnetic perturbations in DIII-D

    SciTech Connect

    Wade, M. R.; Nazikian, R.; deGrassie, John S.; Evans, T. E.; Ferraro, N. M.; Moyer, R. A.; Orlov, D. M.; Buttery, R. J.; Fenstermacher, Max E.; Garofalo, Andrea M.; Lanctot, M. A.; McKee, George R.; Osborne, T. H.; Shafer, M. A.; Solomon, W. M.; Snyder, P. B.; Suttrop, Wolfgang; Wingen, Andreas; Unterberg, Ezekial A.; Zeng, L.

    2015-01-14

    Recent experiments on DIII-D have increased confidence in the ability to suppress edge-localized modes (ELMs) using edge-resonant magnetic perturbations (RMPs) in ITER, including an improved physics basis for the edge response to RMPs as well as expansion of RMP ELM suppression to more ITER-like conditions. In this study, complete ELM suppression has been achieved utilizing n = 3 RMPs in the ITER baseline scenario. In addition, RMP ELM suppression has been expanded to include plasmas with helium concentrations near 25% and the use of n = 2 RMPs. Analysis of the kinetic profile response suggests that ELM suppression is correlated with the co-alignment of the ω⊥e = 0 location, an n = 3 rational surface, and the top of the pedestal. Modelling predicts that such a co-alignment could potentially lead to island (or island chain) formation just inside the top of the pedestal, inhibiting the growth of the pedestal and thereby maintaining the ELM-free state. Detailed analysis of data obtained during toroidal phase variations of the applied n = 3 RMPs have provided further evidence of an island-like structure at the top of the pedestal. In addition, nearly matched discharges with co-neutral-beam-injection (co-NBI) and counter-NBI have demonstrated the importance of the presence of the ω⊥e = 0 location for ELM suppression. Finally, in the counter-NBI cases, the toroidal rotation profile is such that there is no ω⊥e = 0 location and ELMs are not suppressed in conditions in which ELM suppression is generally observed with co-NBI.

  7. Advances in the physics understanding of ELM suppression using resonant magnetic perturbations in DIII-D

    DOE PAGES

    Wade, M. R.; Nazikian, R.; deGrassie, John S.; ...

    2015-01-14

    Recent experiments on DIII-D have increased confidence in the ability to suppress edge-localized modes (ELMs) using edge-resonant magnetic perturbations (RMPs) in ITER, including an improved physics basis for the edge response to RMPs as well as expansion of RMP ELM suppression to more ITER-like conditions. In this study, complete ELM suppression has been achieved utilizing n = 3 RMPs in the ITER baseline scenario. In addition, RMP ELM suppression has been expanded to include plasmas with helium concentrations near 25% and the use of n = 2 RMPs. Analysis of the kinetic profile response suggests that ELM suppression is correlatedmore » with the co-alignment of the ω⊥e = 0 location, an n = 3 rational surface, and the top of the pedestal. Modelling predicts that such a co-alignment could potentially lead to island (or island chain) formation just inside the top of the pedestal, inhibiting the growth of the pedestal and thereby maintaining the ELM-free state. Detailed analysis of data obtained during toroidal phase variations of the applied n = 3 RMPs have provided further evidence of an island-like structure at the top of the pedestal. In addition, nearly matched discharges with co-neutral-beam-injection (co-NBI) and counter-NBI have demonstrated the importance of the presence of the ω⊥e = 0 location for ELM suppression. Finally, in the counter-NBI cases, the toroidal rotation profile is such that there is no ω⊥e = 0 location and ELMs are not suppressed in conditions in which ELM suppression is generally observed with co-NBI.« less

  8. Studies of the physical aspects of intumescence using advance diagnostics methods

    NASA Astrophysics Data System (ADS)

    Saeed, Hussain; Huang, Hua Wei; Zhang, Yang

    2014-04-01

    The use of intumescent paints as an active fire protection method has gained immense interest in recent years. A significant aspect of research has focused on studying the chemical aspects of the system to improve performance. The dynamics and physical aspects of intumescence in real time fire conditions are still unclear. The present research uses an experimental approach where diagnostics techniques such as thermal imaging camera was used to study intumescent characteristics that have been not been reported in great detail. T-panels are a substitute to the most commonly used part in construction, the I-beam. Studies were conducted using a cone calorimeter that provided a uniform heat flux through radiation on steel T-panel samples. The complex nature of char movement was recorded and a novel algorithm was used to track the growing char laye07r. The samples are designed to cater to different fire conditions. Therefore, the degree of intumescence was observed to be very different in the samples. The samples designed for low temperature cellulosic fires focus on high degree of intumesce. Whereas, mechanical strength is the focus for samples used in high temperature turbulent hydrocarbon fire conditions. The variation in the internal structure of the sample is presented. Furthermore, the phenomenon is phase shift is discussed. The phase shift is an essential part of the process of intumescence when the majority of intumescence occurs. It was observed to be different in all the samples. The movement of the samples is a property of great interest. This is because if any part of the substrate is exposed then the formulation does not meet strict commercialisation criterion. The movement was diagonal in nature as compared to flat panels where it is perpendicular. This is due tot the heating pattern of the plate that results in the web part of the panel to influence the growth of char on the flange part of the panel. A special case of char cracking is also highlighted and

  9. Studies of the physical aspects of intumescence using advance diagnostics methods

    SciTech Connect

    Saeed, Hussain Huang, Hua Wei Zhang, Yang

    2014-04-11

    The use of intumescent paints as an active fire protection method has gained immense interest in recent years. A significant aspect of research has focused on studying the chemical aspects of the system to improve performance. The dynamics and physical aspects of intumescence in real time fire conditions are still unclear. The present research uses an experimental approach where diagnostics techniques such as thermal imaging camera was used to study intumescent characteristics that have been not been reported in great detail. T-panels are a substitute to the most commonly used part in construction, the I-beam. Studies were conducted using a cone calorimeter that provided a uniform heat flux through radiation on steel T-panel samples. The complex nature of char movement was recorded and a novel algorithm was used to track the growing char laye07r. The samples are designed to cater to different fire conditions. Therefore, the degree of intumescence was observed to be very different in the samples. The samples designed for low temperature cellulosic fires focus on high degree of intumesce. Whereas, mechanical strength is the focus for samples used in high temperature turbulent hydrocarbon fire conditions. The variation in the internal structure of the sample is presented. Furthermore, the phenomenon is phase shift is discussed. The phase shift is an essential part of the process of intumescence when the majority of intumescence occurs. It was observed to be different in all the samples. The movement of the samples is a property of great interest. This is because if any part of the substrate is exposed then the formulation does not meet strict commercialisation criterion. The movement was diagonal in nature as compared to flat panels where it is perpendicular. This is due tot the heating pattern of the plate that results in the web part of the panel to influence the growth of char on the flange part of the panel. A special case of char cracking is also highlighted and

  10. Atomic force microscopy: a versatile tool to probe the physical and chemical properties of supported membranes at the nanoscale.

    PubMed

    Picas, Laura; Milhiet, Pierre-Emmanuel; Hernández-Borrell, Jordi

    2012-12-01

    Atomic force microscopy (AFM) was developed in the 1980s following the invention of its precursor, scanning tunneling microscopy (STM), earlier in the decade. Several modes of operation have evolved, demonstrating the extreme versatility of this method for measuring the physicochemical properties of samples at the nanoscopic scale. AFM has proved an invaluable technique for visualizing the topographic characteristics of phospholipid monolayers and bilayers, such as roughness, height or laterally segregated domains. Implemented modes such as phase imaging have also provided criteria for discriminating the viscoelastic properties of different supported lipid bilayer (SLB) regions. In this review, we focus on the AFM force spectroscopy (FS) mode, which enables determination of the nanomechanical properties of membrane models. The interpretation of force curves is presented, together with newly emerging techniques that provide complementary information on physicochemical properties that may contribute to our understanding of the structure and function of biomembranes. Since AFM is an imaging technique, some basic indications on how real-time AFM imaging is evolving are also presented at the end of this paper.

  11. First Results of the GPS.DM Observatory: Search for Dark Matter and Exotic Physics with Atomic Clocks and GPS Constellation

    NASA Astrophysics Data System (ADS)

    Roberts, Benjamin; Blewitt, Geoff; Dailey, Conner; Pospelov, Maxim; Rollings, Alex; Sherman, Jeff; Williams, Wyatt; Derevianko, Andrei; GPS. DM Collaboration

    2017-01-01

    Despite the overwhelming cosmological evidence for the existence of dark matter, and the considerable effort of the scientific community over decades, there is no evidence for dark matter in terrestrial experiments. The GPS.DM observatory uses the existing GPS constellation as a 50,000 km-aperture sensor array, analysing the satellite and terrestrial atomic clock data for exotic physics signatures. In particular, the collaboration searches for evidence of transient variations of fundamental constants correlated with the Earth's galactic motion through the dark matter halo. There already exists more than 10 years of good clock timing data that can be used in the search. This type of search is particularly sensitive to exotic forms of dark matter, such as topological defects. Supported by the NSF.

  12. Probing viscoelastic surfaces with bimodal tapping-mode atomic force microscopy: Underlying physics and observables for a standard linear solid model.

    PubMed

    Solares, Santiago D

    2014-01-01

    This paper presents computational simulations of single-mode and bimodal atomic force microscopy (AFM) with particular focus on the viscoelastic interactions occurring during tip-sample impact. The surface is modeled by using a standard linear solid model, which is the simplest system that can reproduce creep compliance and stress relaxation, which are fundamental behaviors exhibited by viscoelastic surfaces. The relaxation of the surface in combination with the complexities of bimodal tip-sample impacts gives rise to unique dynamic behaviors that have important consequences with regards to the acquisition of quantitative relationships between the sample properties and the AFM observables. The physics of the tip-sample interactions and its effect on the observables are illustrated and discussed, and a brief research outlook on viscoelasticity measurement with intermittent-contact AFM is provided.

  13. The Physical Sciences. Report of the National Science Board Submitted to the Congress.

    ERIC Educational Resources Information Center

    Handler, Philip

    Recent advances in the physical sciences, including astronomy, chemical synthesis, chemical dynamics, solid-state sciences, atomic and nuclear science, and elementary particles and high-energy physics are summarized in this report to Congress. The nature of physical science, including its increasing unity, the relationship between science and…

  14. Anti-parity-time symmetry with flying atoms

    NASA Astrophysics Data System (ADS)

    Peng, Peng; Cao, Wanxia; Shen, Ce; Qu, Weizhi; Wen, Jianming; Jiang, Liang; Xiao, Yanhong

    2016-12-01

    The recently developed notion of parity-time (PT) symmetry in optical systems has spawned intriguing prospects. So far, most experimental implementations have been reported in solid-state systems. Here, we report the first experimental demonstration of optical anti-PT symmetry--the counterpart of conventional PT symmetry--in a warm atomic-vapour cell. Rapid coherence transport via flying atoms leads to a dissipative coupling between two long-lived atomic spin waves, allowing for the observation of the essential features of anti-PT symmetry with unprecedented precision on the phase-transition threshold, as well as refractionless light propagation. Moreover, we show that a linear or nonlinear interaction between the two spatially separated beams can be achieved. Our results advance non-Hermitian physics by bridging to the field of atomic, molecular and optical physics, where new phenomena and applications in quantum and nonlinear optics aided by (anti-)PT symmetry could be anticipated.

  15. PREFACE: Papers from the 17th European Conference on Atomic and Molecular Physics of Ionized Gases (Constanta, Romania, 1 5 September 2004)

    NASA Astrophysics Data System (ADS)

    Ciupina, V.; Musa, G.; Vladoiu, R.

    2005-05-01

    The 17th European Conference on Atomic and Molecular Physics of Ionized Gases (ESCAMPIG-17) was held in Constanta, Romania, on 1-5 September 2004. ESCAMPIG is an important biennial European conference at which useful exchanges of ideas and discussion of new achievements in low temperature plasma physics take place. The meeting was held in the ambient location of Constanta, Romania, which provided the perfect location to encourage interaction between the related research communities attending the conference. The local organizers, as well as the plasma scientists of Romania, were all very much honoured that Constanta was selected by the International Scientific Committee as the location for ESCAMPIG-17. The conference was the second largest plasma physics conference ever to take place in Romania, second only to the ICPIG conference of 1969 in Bucharest—a huge conference with four parallel sections and simultaneous translation in four languages (English, German, French and Russian) in all four parallel sections. In contrast, ESCAMPIG-17 maintained the founding ideals and held single sessions only to encourage and strengthen the relationships between research communities. During ESCAMPIG-17 we had the opportunity to attend and hear excellent invited lectures presenting outstanding new results in plasma physics. A selection of those invited lectures from ESCAMPIG-17 is published in this issue of Plasma Sources Science and Technology. We would like to take this opportunity to express our thanks to all the invited lecturers and also to all the participants who attended ESCAMPIG-17. The Local Organizing Committee would particularly like to thank all the International Scientific Committee members. Special thanks are due to Professor Gerrit Kroesen and Professor Nader Sadeghi for their valuable and continuous support in solving our problems, no matter how complicated they were.

  16. Physics of a two-dimensional electron gas with cold atoms in non-Abelian gauge potentials

    NASA Astrophysics Data System (ADS)

    Satija, Indubala I.; Dakin, Daniel C.; Vaishnav, J. Y.; Clark, Charles W.

    2008-04-01

    Motivated by the possibility of creating non-Abelian fields using cold atoms in optical lattices, we explore the richness and complexity of noninteracting two-dimensional electron gases (2DEGs) in a lattice, subjected to such fields. In the continuum limit, a non-Abelian system characterized by a two-component “magnetic flux” describes a harmonic oscillator existing in two different charge states (mimicking a particle-hole pair) where the coupling between the states is determined by the non-Abelian parameter, namely, the difference between the two components of the “magnetic flux.” A key feature of the non-Abelian system is a splitting of the Landau energy levels, which broaden into bands, as the spectrum depends explicitly on the transverse momentum. These Landau bands result in a coarse-grained “moth,” a continuum version of the generalized Hofstadter butterfly. Furthermore, the bands overlap, leading to effective relativistic effects. Importantly, similar features also characterize the corresponding two-dimensional lattice problem when at least one of the components of the magnetic flux is an irrational number. The lattice system with two competing “magnetic fluxes” penetrating the unit cell provides a rich environment in which to study localization phenomena. Some unique aspects of the transport properties of the non-Abelian system are the possibility of inducing localization by varying the quasimomentum, and the absence of localization of certain zero-energy states exhibiting a linear energy-momentum relation. Furthermore, non-Abelian systems provide an interesting localization scenario where the localization transition is accompanied by a transition from relativistic to nonrelativistic theory.

  17. Financial Distress and Its Associations With Physical and Emotional Symptoms and Quality of Life Among Advanced Cancer Patients

    PubMed Central

    Ferrer, Jeanette; Rieber, Alyssa G.; Rhondali, Wadih; Tayjasanant, Supakarn; Ochoa, Jewel; Cantu, Hilda; Chisholm, Gary; Williams, Janet; Frisbee-Hume, Susan; Bruera, Eduardo

    2015-01-01

    Objective. There are limited data on the effects of financial distress (FD) on overall suffering and quality of life (QOL) of patients with advanced cancer (AdCa). In this cross-sectional study, we examined the frequency of FD and its correlates in AdCa. Patients and Methods. We interviewed 149 patients, 77 at a comprehensive cancer center (CCC) and 72 at a general public hospital (GPH). AdCa completed a self-rated FD (subjective experience of distress attributed to financial problems) numeric rating scale (0 = best, 10 = worst) and validated questionnaires assessing symptoms (Edmonton Symptom Assessment System [ESAS]), psychosocial distress (Hospital Anxiety and Depression Scale [HADS]), and QOL (Functional Assessment of Cancer Therapy-General [FACT-G]). Results. The patients’ median age was 60 years (95% confidence interval [CI]: 58.6–61.5 years); 74 (50%) were female; 48 of 77 at CCC (62%) versus 13 of 72 at GPH (18%) were white; 21 of 77 (27%) versus 32 of 72 (38%) at CCC and GPH, respectively, were black; and 7 of 77 (9%) versus 27 of 72 (38%) at CCC and GPH, respectively, were Hispanic (p < .0001). FD was present in 65 of 75 at CCC (86%; 95% CI: 76%–93%) versus 65 of 72 at GPH (90%; 95% CI: 81%–96%; p = .45). The median intensity of FD at CCC and GPH was 4 (interquartile range [IQR]: 1–7) versus 8 (IQR: 3–10), respectively (p = .0003). FD was reported as more severe than physical distress, distress about physical functioning, social/family distress, and emotional distress by 45 (30%), 46 (31%), 64 (43%), and 55 (37%) AdCa, respectively (all significantly worse for patients at GPH) (p < .05). AdCa reported that FD was affecting their general well-being (0 = not at all, 10 = very much) with a median score of 5 (IQR: 1–8). FD correlated (Spearman correlation) with FACT-G (r = −0.23, p = .0057); HADS-anxiety (r = .27, p = .0014), ESAS-anxiety (r = .2, p = .0151), and ESAS-depression (r = .18, p = .0336). Conclusion. FD was very frequent in both

  18. The Brazilian time and frequency atomic standards program.

    PubMed

    Ahmed, Mushtaq; Magalhães, Daniel V; Bebeachibuli, Aida; Müller, Stella T; Alves, Renato F; Ortega, Tiago A; Weiner, John; Bagnato, Vanderlei S

    2008-06-01

    Cesium atomic beam clocks have been the workhorse for many demanding applications in science and technology for the past four decades. Tests of the fundamental laws of physics and the search for minute changes in fundamental constants, the synchronization of telecommunication networks, and realization of the satellite-based global positioning system would not be possible without atomic clocks. The adoption of optical cooling and trapping techniques, has produced a major advance in atomic clock precision. Cold-atom fountain and compact cold-atom clocks have also been developed. Measurement precision of a few parts in 10(15) has been demonstrated for a cold-atom fountain clock. We present here an overview of the time and frequency metrology program based on cesium atoms under development at USP São Carlos. This activity consists of construction and characterization of atomic-beam, and several variations of cold-atom clocks. We discuss the basic working principles, construction, evaluation, and important applications of atomic clocks in the Brazilian program.

  19. Exploring the relationship between the engineering and physical sciences and the health and life sciences by advanced bibliometric methods.

    PubMed

    Waltman, Ludo; van Raan, Anthony F J; Smart, Sue

    2014-01-01

    We investigate the extent to which advances in the health and life sciences (HLS) are dependent on research in the engineering and physical sciences (EPS), particularly physics, chemistry, mathematics, and engineering. The analysis combines two different bibliometric approaches. The first approach to analyze the 'EPS-HLS interface' is based on term map visualizations of HLS research fields. We consider 16 clinical fields and five life science fields. On the basis of expert judgment, EPS research in these fields is studied by identifying EPS-related terms in the term maps. In the second approach, a large-scale citation-based network analysis is applied to publications from all fields of science. We work with about 22,000 clusters of publications, each representing a topic in the scientific literature. Citation relations are used to identify topics at the EPS-HLS interface. The two approaches complement each other. The advantages of working with textual data compensate for the limitations of working with citation relations and the other way around. An important advantage of working with textual data is in the in-depth qualitative insights it provides. Working with citation relations, on the other hand, yields many relevant quantitative statistics. We find that EPS research contributes to HLS developments mainly in the following five ways: new materials and their properties; chemical methods for analysis and molecular synthesis; imaging of parts of the body as well as of biomaterial surfaces; medical engineering mainly related to imaging, radiation therapy, signal processing technology, and other medical instrumentation; mathematical and statistical methods for data analysis. In our analysis, about 10% of all EPS and HLS publications are classified as being at the EPS-HLS interface. This percentage has remained more or less constant during the past decade.

  20. Exploring the Relationship between the Engineering and Physical Sciences and the Health and Life Sciences by Advanced Bibliometric Methods

    PubMed Central

    Waltman, Ludo; van Raan, Anthony F. J.; Smart, Sue

    2014-01-01

    We investigate the extent to which advances in the health and life sciences (HLS) are dependent on research in the engineering and physical sciences (EPS), particularly physics, chemistry, mathematics, and engineering. The analysis combines two different bibliometric approaches. The first approach to analyze the ‘EPS-HLS interface’ is based on term map visualizations of HLS research fields. We consider 16 clinical fields and five life science fields. On the basis of expert judgment, EPS research in these fields is studied by identifying EPS-related terms in the term maps. In the second approach, a large-scale citation-based network analysis is applied to publications from all fields of science. We work with about 22,000 clusters of publications, each representing a topic in the scientific literature. Citation relations are used to identify topics at the EPS-HLS interface. The two approaches complement each other. The advantages of working with textual data compensate for the limitations of working with citation relations and the other way around. An important advantage of working with textual data is in the in-depth qualitative insights it provides. Working with citation relations, on the other hand, yields many relevant quantitative statistics. We find that EPS research contributes to HLS developments mainly in the following five ways: new materials and their properties; chemical methods for analysis and molecular synthesis; imaging of parts of the body as well as of biomaterial surfaces; medical engineering mainly related to imaging, radiation therapy, signal processing technology, and other medical instrumentation; mathematical and statistical methods for data analysis. In our analysis, about 10% of all EPS and HLS publications are classified as being at the EPS-HLS interface. This percentage has remained more or less constant during the past decade. PMID:25360616