Sample records for microstructured paul trap

  1. High-Fidelity Preservation of Quantum Information During Trapped-Ion Transport

    NASA Astrophysics Data System (ADS)

    Kaufmann, Peter; Gloger, Timm F.; Kaufmann, Delia; Johanning, Michael; Wunderlich, Christof

    2018-01-01

    A promising scheme for building scalable quantum simulators and computers is the synthesis of a scalable system using interconnected subsystems. A prerequisite for this approach is the ability to faithfully transfer quantum information between subsystems. With trapped atomic ions, this can be realized by transporting ions with quantum information encoded into their internal states. Here, we measure with high precision the fidelity of quantum information encoded into hyperfine states of a Yb171 + ion during ion transport in a microstructured Paul trap. Ramsey spectroscopy of the ion's internal state is interleaved with up to 4000 transport operations over a distance of 280 μ m each taking 12.8 μ s . We obtain a state fidelity of 99.9994 (-7+6) % per ion transport.

  2. Stable Trapping of Multielectron Helium Bubbles in a Paul Trap

    NASA Astrophysics Data System (ADS)

    Joseph, E. M.; Vadakkumbatt, V.; Pal, A.; Ghosh, A.

    2017-06-01

    In a recent experiment, we have used a linear Paul trap to store and study multielectron bubbles (MEBs) in liquid helium. MEBs have a charge-to-mass ratio (between 10^{-4} and 10^{-2} C/kg) which is several orders of magnitude smaller than ions (between 10^6 and 10^8 C/kg) studied in traditional ion traps. In addition, MEBs experience significant drag force while moving through the liquid. As a result, the experimental parameters for stable trapping of MEBs, such as magnitude and frequency of the applied electric fields, are very different from those used in typical ion trap experiments. The purpose of this paper is to model the motion of MEBs inside a linear Paul trap in liquid helium, determine the range of working parameters of the trap, and compare the results with experiments.

  3. System and method for trapping and measuring a charged particle in a liquid

    DOEpatents

    Reed, Mark A; Krstic, Predrag S; Guan, Weihua; Zhao, Xiongce

    2013-07-23

    A system and method for trapping a charged particle is disclosed. A time-varying periodic multipole electric potential is generated in a trapping volume. A charged particle under the influence of the multipole electric field is confined to the trapping volume. A three electrode configuration giving rise to a 3D Paul trap and a four planar electrode configuration giving rise to a 2D Paul trap are disclosed.

  4. System and method for trapping and measuring a charged particle in a liquid

    DOEpatents

    Reed, Mark A; Krstic, Predrag S; Guan, Weihua; Zhao, Xiongce

    2012-10-23

    A system and method for trapping a charged particle is disclosed. A time-varying periodic multipole electric potential is generated in a trapping volume. A charged particle under the influence of the multipole electric field is confined to the trapping volume. A three electrode configuration giving rise to a 3D Paul trap and a four planar electrode configuration giving rise to a 2D Paul trap are disclosed.

  5. Microfabricated linear Paul-Straubel ion trap

    DOEpatents

    Mangan, Michael A [Albuquerque, NM; Blain, Matthew G [Albuquerque, NM; Tigges, Chris P [Albuquerque, NM; Linker, Kevin L [Albuquerque, NM

    2011-04-19

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  6. Ion-neutral-atom sympathetic cooling in a hybrid linear rf Paul and magneto-optical trap

    NASA Astrophysics Data System (ADS)

    Goodman, D. S.; Sivarajah, I.; Wells, J. E.; Narducci, F. A.; Smith, W. W.

    2012-09-01

    Long-range polarization forces between ions and neutral atoms result in large elastic scattering cross sections (e.g., ˜106a.u. for Na-Na+ or Na-Ca+ at cold and ultracold temperatures). This suggests that a hybrid ion-neutral trap should offer a general means for significant sympathetic cooling of atomic or molecular ions. We present simion 7.0 simulation results concerning the advantages and limitations of sympathetic cooling within a hybrid trap apparatus consisting of a linear rf Paul trap concentric with a Na magneto-optical trap (MOT). This paper explores the impact of various heating mechanisms on the hybrid system and how parameters related to the MOT, Paul trap, number of ions, and ion species affect the efficiency of the sympathetic cooling.

  7. Paul Trap Simulator Experiment (PTSX) to simulate intense beam propagation through a periodic focusing quadrupole field

    NASA Astrophysics Data System (ADS)

    Davidson, Ronald C.; Efthimion, Philip C.; Gilson, Erik; Majeski, Richard; Qin, Hong

    2002-01-01

    The Paul Trap Simulator Experiment (PTSX) is under construction at the Princeton Plasma Physics Laboratory to simulate intense beam propagation through a periodic quadrupole magnetic field. In the Paul trap configuration, a long nonneutral plasma column is confined axially by dc voltages on end cylinders at z=+L and z=-L, and transverse confinement is provided by segmented cylindrical electrodes with applied oscillatory voltages ±V0(t) over 90° segments. Because the transverse focusing force is similar in waveform to that produced by a discrete set of periodic quadrupole magnets in a frame moving with the beam, the Paul trap configuration offers the possibility of simulating intense beam propagation in a compact laboratory facility. The experimental layout is described, together with the planned experiments to study beam mismatch, envelope instabilities, halo particle production, and collective wave excitations.

  8. Design of blade-shaped-electrode linear ion traps with reduced anharmonic contributions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deng, K.; Che, H.; Ge, Y. P.

    2015-09-21

    RF quadrupole linear Paul traps are versatile tools in quantum physics experiments. Linear Paul traps with blade-shaped electrodes have the advantages of larger solid angles for fluorescence collection. But with these kinds of traps, the existence of higher-order anharmonic terms of the trap potentials can cause large heating rate for the trapped ions. In this paper, we theoretically investigate the dependence of higher-order terms of trap potentials on the geometry of blade-shaped traps, and offer an optimized design. A modified blade electrodes trap is proposed to further reduce higher-order anharmonic terms while still retaining large fluorescence collection angle.

  9. Use of a Linear Paul Trap to Study Random Noise-Induced Beam Degradation in High-Intensity Accelerators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, Moses; Gilson, Erik P.; Davidson, Ronald C.

    2009-04-10

    A random noise-induced beam degradation that can affect intense beam transport over long propagation distances has been experimentally studied by making use of the transverse beam dynamics equivalence between an alternating-gradient (AG) focusing system and a linear Paul trap system. For the present studies, machine imperfections in the quadrupole focusing lattice are considered, which are emulated by adding small random noise on the voltage waveform of the quadrupole electrodes in the Paul trap. It is observed that externally driven noise continuously produces a nonthermal tail of trapped ions, and increases the transverse emittance almost linearly with the duration of themore » noise.« less

  10. Surface-electrode point Paul trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Tony Hyun; Herskind, Peter F.; Chuang, Isaac L.

    2010-10-15

    We present a model as well as experimental results for a surface electrode radiofrequency Paul trap that has a circular electrode geometry well suited for trapping single ions and two-dimensional planar ion crystals. The trap design is compatible with microfabrication and offers a simple method by which the height of the trapped ions above the surface may be changed in situ. We demonstrate trapping of single {sup 88}Sr{sup +} ions over an ion height range of 200-1000 {mu}m for several hours under Doppler laser cooling and use these to characterize the trap, finding good agreement with our model.

  11. Rotating Saddle Paul Trap.

    ERIC Educational Resources Information Center

    Rueckner, Wolfgang; And Others

    1995-01-01

    Describes a demonstration in which a ball is placed in an unstable position on a saddle shape. The ball becomes stable when it is rotated above some threshold angular velocity. The demonstration is a mechanical analog of confining a particle in a "Paul Trap". (DDR)

  12. Asymptotic solution of Fokker-Planck equation for plasma in Paul traps

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shah, Kushal

    2010-05-15

    An exact analytic solution of the Vlasov equation for the plasma distribution in a Paul trap is known to be a Maxwellian and thus, immune to collisions under the assumption of infinitely fast relaxation [K. Shah and H. S. Ramachandran, Phys. Plasmas 15, 062303 (2008)]. In this paper, it is shown that even for a more realistic situation of finite time relaxation, solutions of the Fokker-Planck equation lead to an equilibrium solution of the form of a Maxwellian with oscillatory temperature. This shows that the rf heating observed in Paul traps cannot be caused due to collisional effects alone.

  13. Electron spin resonance from NV centers in diamonds levitating in an ion trap

    NASA Astrophysics Data System (ADS)

    Delord, T.; Nicolas, L.; Schwab, L.; Hétet, G.

    2017-03-01

    We report observations of the electron spin resonance (ESR) of nitrogen vacancy centers in diamonds that are levitating in an ion trap. Using a needle Paul trap operating under ambient conditions, we demonstrate efficient microwave driving of the electronic spin and show that the spin properties of deposited diamond particles measured by the ESR are retained in the Paul trap. We also exploit the ESR signal to show angle stability of single trapped mono-crystals, a necessary step towards spin-controlled levitating macroscopic objects.

  14. A transportable Paul-trap for levitation and accurate positioning of micron-scale particles in vacuum for laser-plasma experiments

    NASA Astrophysics Data System (ADS)

    Ostermayr, T. M.; Gebhard, J.; Haffa, D.; Kiefer, D.; Kreuzer, C.; Allinger, K.; Bömer, C.; Braenzel, J.; Schnürer, M.; Cermak, I.; Schreiber, J.; Hilz, P.

    2018-01-01

    We report on a Paul-trap system with large access angles that allows positioning of fully isolated micrometer-scale particles with micrometer precision as targets in high-intensity laser-plasma interactions. This paper summarizes theoretical and experimental concepts of the apparatus as well as supporting measurements that were performed for the trapping process of single particles.

  15. Ion Trap Quantum Computing

    DTIC Science & Technology

    2011-12-01

    quantum computer architecture schemes, but there are several problems that will be discussed later. 15 IV. ION TRAPS Wolfgang Paul was the first...famous physics experiment [62]. Wolfgang Paul demonstrated a similar apparatus during his Nobel Prize speech [63]. This device is hyperbolic-parabolic...Although it does not apply to linear traps, it is useful to understand the interaction between the Coulomb force and the repulsive quantum-mechanical Pauli

  16. Charged particle capturing in air flow by linear Paul trap

    NASA Astrophysics Data System (ADS)

    Lapitsky, D. S.; Filinov, V. S.; Vladimirov, V. I.; Syrovatka, R. A.; Vasilyak, L. M.; Pecherkin, V. Ya; Deputatova, L. V.

    2018-01-01

    The paper presents the simulation results of micro- and nanoparticle capturing in an air flows by linear Paul traps in assumption that particles gain their charges in corona discharge, its electric field strength is restricted by Paschen equation and spherical shape of particles.

  17. Demonstrating the Principle of an rf Paul Ion Trap

    NASA Astrophysics Data System (ADS)

    Johnson, Andrew; Rabchuk, James

    2008-03-01

    An rf ion trap uses a time-varying electric field to trap charged ions. This is useful in applications related to quantum computing and mass spectroscopy. There are several mechanical devices described in the literature which have attempted to provide illustrative demonstrations of the principle of rf ion traps, including a mechanically-rotating ``saddle trap'' and the vertically-driven, inverted pendulum^1,2. Neither demonstration, however, successfully demonstrates BOTH the sinusoidal variation in the electric potential of the rf trap AND the parametric stability of the ions in the trap described by Mathieu's equation. We have modified a design of a one-dimensional ponderomotive trap^3 so that it satisfies both criteria for demonstrating the principle of an rf Paul trap. Our studies indicate that trapping stability is highly sensitive to fluxuations in the driving frequency. Results from the demonstration apparatus constructed by the authors will be presented. ^1 Rueckner, W., et al., ``Rotating saddle Paul trap,'' Am. J. Phys., 63 (2), February 1995. ^2 Friedman, M.H., et al., ``The inverted pendulum: A mechanical analogue of a quadrupole mass filter,'' Am. J. Phys., 50 (10), October 1982. ^3 Johnson, A.K. and Rabchuk, J.A., ``A One-Dimensional Ponderomotive Trap,'' ISAAPT 2007 spring meeting, WIU, March 30, 2007.

  18. Production of Ar{sup q+} ions with a tandem linear Paul trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Higaki, H., E-mail: hhigaki@hiroshima-u.ac.jp; Nagayasu, K.; Iwai, T.

    A tandem linear Paul trap was used to create highly charged Argon ions by electron impact ionizations. By improving the operation scheme, the production of Ar{sup 4+} ions was confirmed. Possible improvements for the future experiments with laser cooled Ca{sup +} ions are suggested.

  19. A Long DNA Segment in a Linear Nanoscale Paul Trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Joseph, Sony nmn; Guan, Weihau; Reed, Mark A

    2009-01-01

    We study the dynamics of a linearly distributed line charge such as single stranded DNA (ssDNA) in a nanoscale, linear 2D Paul trap in vacuum. Using molecular dynamics simulations we show that a line charge can be trapped effectively in the trap for a well defined range of stability parameters. We investigated (i) a flexible bonded string of charged beads and (ii) a ssDNA polymer of variable length, for various trap parameters. A line charge undergoes oscillations or rotations as it moves, depending on its initial angle, the position of the center of mass and the velocity. The stability regionmore » for a strongly bonded line of charged beads is similar to that of a single ion with the same charge to mass ratio. Single stranded DNA as long as 40 nm does not fold or curl in the Paul trap, but could undergo rotations about the center of mass. However, we show that a stretching field in the axial direction can effectively prevent the rotations and increase the confinement stability.« less

  20. Control of Screening of a Charged Particle in Electrolytic Aqueous Paul Trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Jae Hyun nmn; Krstic, Predrag S

    2011-01-01

    Individual charged particles could be trapped and confined in the combined radio-frequency and DC quadrupole electric field of an aqueous Paul trap. Viscosity of water improves confinement and extends the range of the trap parameters which characterize the stability of the trap. Electrolyte, if present in aqueous solution, may screen the charged particle and thus partially or fully suppress electrophoretic interaction with the applied filed, possibly reducing it to a generally much weaker dielectrophoretic interaction with an induced dipole. Applying molecular dynamics simulation we show that the quadrupole field has a different affects at the electrolyte ions and at muchmore » heavier charged particle, effectively eliminating the screening effect and reinstating the electrophoretic confinement.« less

  1. Control Of Screening Of A Charged Particle In Electrolytic Aqueous Paul Trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Jae Hyun; Krstic, Predrag S.

    2011-06-01

    Individual charged particles could be trapped and confined by the combined radio-frequency and DC quadrupole electric field of an aqueous Paul trap. Viscosity of water improves confinement and extends the range of the trap parameters which characterize the stability of the trap. Electrolyte, if present in aqueous solution, may screen the charged particle and thus partially or fully suppress electrophoretic interaction with the applied filed, possibly reducing it to a generally much weaker dielectrophoretic interaction with an induced dipole. Applying molecular dynamics simulation we show that the quadrupole field has a different effect at the electrolyte ions and at muchmore » heavier charged particle, effectively eliminating the screening by electrolyte ions and reinstating the electrophoretic confinement.« less

  2. Paul trapping of charged particles in aqueous solution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guan, Weihau; Reed, Mark A; Joseph, Sony nmn

    2011-01-01

    We experimentally demonstrate the feasibility of an aqueous Paul trap using a proof-of-principle planar device. Radio frequency voltages are used to generate an alternating focusing/defocusing potential well in two orthogonal directions. Individual charged particles are dynamically confined into nanometer scale in space. Compared with conventional Paul traps working in frictionless vacuum, the aqueous environment associated with damping forces and thermally induced fluctuations (Brownian noise) exerts a fundamental influence on the underlying physics. We investigate the impact of these two effects on the confining dynamics, with the aim to reduce the rms value of the positional fluctuations. We find that themore » rms fluctuations can be modulated by adjusting the voltages and frequencies. This technique provides an alternative for the localization and control of charged particles in an aqueous environment.« less

  3. Nonlinear resonances in linear segmented Paul trap of short central segment.

    PubMed

    Kłosowski, Łukasz; Piwiński, Mariusz; Pleskacz, Katarzyna; Wójtewicz, Szymon; Lisak, Daniel

    2018-03-23

    Linear segmented Paul trap system has been prepared for ion mass spectroscopy experiments. A non-standard approach to stability of trapped ions is applied to explain some effects observed with ensembles of calcium ions. Trap's stability diagram is extended to 3-dimensional one using additional ∆a besides standard q and a stability parameters. Nonlinear resonances in (q,∆a) diagrams are observed and described with a proposed model. The resonance lines have been identified using simple simulations and comparing the numerical and experimental results. The phenomenon can be applied in electron-impact ionization experiments for mass-identification of obtained ions or purification of their ensembles. This article is protected by copyright. All rights reserved.

  4. Cavity cooling a single charged levitated nanosphere.

    PubMed

    Millen, J; Fonseca, P Z G; Mavrogordatos, T; Monteiro, T S; Barker, P F

    2015-03-27

    Optomechanical cavity cooling of levitated objects offers the possibility for laboratory investigation of the macroscopic quantum behavior of systems that are largely decoupled from their environment. However, experimental progress has been hindered by particle loss mechanisms, which have prevented levitation and cavity cooling in a vacuum. We overcome this problem with a new type of hybrid electro-optical trap formed from a Paul trap within a single-mode optical cavity. We demonstrate a factor of 100 cavity cooling of 400 nm diameter silica spheres trapped in vacuum. This paves the way for ground-state cooling in a smaller, higher finesse cavity, as we show that a novel feature of the hybrid trap is that the optomechanical cooling becomes actively driven by the Paul trap, even for singly charged nanospheres.

  5. Cavity Cooling a Single Charged Levitated Nanosphere

    NASA Astrophysics Data System (ADS)

    Millen, J.; Fonseca, P. Z. G.; Mavrogordatos, T.; Monteiro, T. S.; Barker, P. F.

    2015-03-01

    Optomechanical cavity cooling of levitated objects offers the possibility for laboratory investigation of the macroscopic quantum behavior of systems that are largely decoupled from their environment. However, experimental progress has been hindered by particle loss mechanisms, which have prevented levitation and cavity cooling in a vacuum. We overcome this problem with a new type of hybrid electro-optical trap formed from a Paul trap within a single-mode optical cavity. We demonstrate a factor of 100 cavity cooling of 400 nm diameter silica spheres trapped in vacuum. This paves the way for ground-state cooling in a smaller, higher finesse cavity, as we show that a novel feature of the hybrid trap is that the optomechanical cooling becomes actively driven by the Paul trap, even for singly charged nanospheres.

  6. A molecular dynamics simulation study on trapping ions in a nanoscale Paul trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Xiongce; Krstic, Predrag S

    2008-01-01

    We found by molecular dynamics simulations that a low energy ion can be trapped effectively in a nanoscale Paul trap in both vacuum and in aqueous environment when appropriate AC/DC electric fields are applied to the system. Using the negatively charged chlorine ion as an example, we show that the trapped ion oscillates around the center of the nanotrap with the amplitude dependent on the parameters of the system and applied voltage. Successful trapping of the ion within nanoseconds requires electric bias of GHz frequency, in the range of hundreds of mV. The oscillations are damped in the aqueous environment,more » but polarization of the water molecules requires application of the higher voltage biases to reach the improved stability of the trapping. Application of a supplemental DC driving field along the trap axis can effectively drive the ion off the trap center and out of the trap, opening a possibility of studying DNA and other biological molecules using embedded probes while achieving a full control of their translocation and localization in the trap.« less

  7. Designing of a Quadrupole Paul Ion Trap

    NASA Astrophysics Data System (ADS)

    Kiyani, Abouzar; Abdollahzadeh, M.; Sadat Kiai, S. M.; Zirak, A. R.

    2011-08-01

    The ion motion equation in a Paul ion trap known as Mathieu differential equation has been solved for the first time by using Runge-Kutta methods with 4th, 6th, and 8th orders. The first stability regions in az - qz plane and the corresponding qmax values were determined and compared. Also, the first stability regions of , , , ions in the Vdc - Vac plane were drown, and the threshold voltages for the ion separation was investigated.

  8. Measurement of isotope ratio of Ca{sup +} ions in a linear Paul Trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashimoto, Y.; Minamino, K.; Nagamoto, D.

    2009-03-17

    Measurement of isotope ratios of Calcium is very useful in many fields. So we demonstrated the measurement of isotope ratios of {sup 40}Ca{sup +}(abundance 96.4%) to {sup 44}Ca{sup +}(2.09%) ions in a linear Paul trap with several laser lights tuning to the isotope shifts. And we found that the experimental parameters had large influences on the measurement of the isotope ratios.

  9. Dipole Excitation With A Paul Ion Trap Mass Spectrometer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    MacAskill, J. A.; Madzunkov, S. M.; Chutjian, A.

    Preliminary results are presented for the use of an auxiliary radiofrequency (rf) excitation voltage in combination with a high purity, high voltage rf generator to perform dipole excitation within a high precision Paul ion trap. These results show the effects of the excitation frequency over a continuous frequency range on the resultant mass spectra from the Paul trap with particular emphasis on ion ejection times, ion signal intensity, and peak shapes. Ion ejection times are found to decrease continuously with variations in dipole frequency about several resonant values and show remarkable symmetries. Signal intensities vary in a complex fashion withmore » numerous resonant features and are driven to zero at specific frequency values. Observed intensity variations depict dipole excitations that target ions of all masses as well as individual masses. Substantial increases in mass resolution are obtained with resolving powers for nitrogen increasing from 114 to 325.« less

  10. Scalable Creation of Long-Lived Multipartite Entanglement

    NASA Astrophysics Data System (ADS)

    Kaufmann, H.; Ruster, T.; Schmiegelow, C. T.; Luda, M. A.; Kaushal, V.; Schulz, J.; von Lindenfels, D.; Schmidt-Kaler, F.; Poschinger, U. G.

    2017-10-01

    We demonstrate the deterministic generation of multipartite entanglement based on scalable methods. Four qubits are encoded in 40Ca+, stored in a microstructured segmented Paul trap. These qubits are sequentially entangled by laser-driven pairwise gate operations. Between these, the qubit register is dynamically reconfigured via ion shuttling operations, where ion crystals are separated and merged, and ions are moved in and out of a fixed laser interaction zone. A sequence consisting of three pairwise entangling gates yields a four-ion Greenberger-Horne-Zeilinger state |ψ ⟩=(1 /√{2 })(|0000 ⟩+|1111 ⟩) , and full quantum state tomography reveals a state fidelity of 94.4(3)%. We analyze the decoherence of this state and employ dynamic decoupling on the spatially distributed constituents to maintain 69(5)% coherence at a storage time of 1.1 sec.

  11. Paul Ion Trap as a Diagnostic for Plasma Focus

    NASA Astrophysics Data System (ADS)

    Sadat Kiai, S. M.; Adlparvar, S.; Zirak, A.; Alhooie, Samira; Elahi, M.; Sheibani, S.; Safarien, A.; Farhangi, S.; Dabirzadeh, A. A.; Khalaj, M. M.; Mahlooji, M. S.; KaKaei, S.; Talaei, A.; Kashani, A.; Tajik Ahmadi, H.; Zahedi, F.

    2010-02-01

    The plasma discharge contamination by high and low Z Impurities affect the rate of nuclear fusion reaction products, specially when light particles have to be confined. These impurities should be analyzed and can be fairly controlled. This paper reports on the development of a Paul ion trap with ion sources by impact electron ionization as a diagnostic for the 10 kJ Iranian sunshine plasma focus device. Preliminary results of the residual gas are analyzed and presented.

  12. Dynamics of charged particles in a Paul radio-frequency quadrupole trap

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Williams, A.; Maleki, L.; Djomehri, M. J.; Harabetian, E.

    1991-01-01

    A molecular-dynamics simulation of hundreds of ions confined in a Paul trap has been performed. The simulation includes the trapped particles' micromotion and interparticle Coulomb interactions. A random walk in velocity was implemented to bring the secular motion to a given temperature which was numerically measured. When the coupling Gamma is large the ions from concentric shells which undergo a quadrupole oscillation at the RF frequency, while the ions within a shell form a 2D hexagonal lattice. Ion clouds at 5 mK show no RF heating for q(z) less than about 0.6, whereas rapid heating is seen for qz = 0.8.

  13. Exploring the Effects of Demographic, Economic, and Social Factors on China’s Economy

    DTIC Science & Technology

    2012-12-14

    bleached mushrooms and dyed raspberries and hormone- injected milk,” many foreigners chose to leave China, an option not available to Chinese...elasticity-pessimism-and-the-renminbi-wonkish/ (accessed 27 August 2012); Paul Krugman, “How Much of the World is in a Liquidity Trap?” New 32...York Times, 17 March 2010, http://krugman.blogs.nytimes.com/2010/03/17/how-much- of-the-world-is-in-a- liquidity -trap/ (accessed 27 August 2012); Paul

  14. Paul Trapping of Radioactive {sup 6}He{sup +} Ions and Direct Observation of Their {beta} Decay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flechard, X.; Lienard, E.; Mery, A.

    2008-11-21

    We demonstrate that abundant quantities of short-lived {beta} unstable ions can be trapped in a novel transparent Paul trap and that their decay products can directly be detected in coincidence. Low energy {sup 6}He{sup +} (807 ms half-life) ions were extracted from the SPIRAL source at GANIL, then decelerated, cooled, and bunched by means of the buffer gas cooling technique. More than 10{sup 8} ions have been stored over a measuring period of six days, and about 10{sup 5} decay coincidences between the beta particles and the {sup 6}Li{sup ++} recoiling ions have been recorded. The technique can be extendedmore » to other short-lived species, opening new possibilities for trap assisted decay experiments.« less

  15. Preliminary Tests of a Paul ion Trap as an Ion Source

    NASA Astrophysics Data System (ADS)

    Sadat Kiai, S. M.; Zirak, A. R.; Elahi, M.; Adlparvar, S.; Mortazavi, B. N.; Safarien, A.; Farhangi, S.; Sheibani, S.; Alhooie, S.; Khalaj, M. M. A.; Dabirzadeh, A. A.; Ruzbehani, M.; Zahedi, F.

    2010-10-01

    The paper reports on the design and construction of a Paul ion trap as an ion source by using an impact electron ionization technique. Ions are produced in the trap and confined for the specific time which is then extracted and detected by a Faraday cup. Especial electronic configurations are employed between the end caps, ring electrodes, electron gun and a negative voltage for the detector. This configuration allows a constant low level of pure ion source between the pulsed confined ion sources. The present experimental results are based on the production and confinement of Argon ions with good stability and repeatability, but in principle, the technique can be used for various Argon like ions.

  16. Scalable Creation of Long-Lived Multipartite Entanglement.

    PubMed

    Kaufmann, H; Ruster, T; Schmiegelow, C T; Luda, M A; Kaushal, V; Schulz, J; von Lindenfels, D; Schmidt-Kaler, F; Poschinger, U G

    2017-10-13

    We demonstrate the deterministic generation of multipartite entanglement based on scalable methods. Four qubits are encoded in ^{40}Ca^{+}, stored in a microstructured segmented Paul trap. These qubits are sequentially entangled by laser-driven pairwise gate operations. Between these, the qubit register is dynamically reconfigured via ion shuttling operations, where ion crystals are separated and merged, and ions are moved in and out of a fixed laser interaction zone. A sequence consisting of three pairwise entangling gates yields a four-ion Greenberger-Horne-Zeilinger state |ψ⟩=(1/sqrt[2])(|0000⟩+|1111⟩), and full quantum state tomography reveals a state fidelity of 94.4(3)%. We analyze the decoherence of this state and employ dynamic decoupling on the spatially distributed constituents to maintain 69(5)% coherence at a storage time of 1.1 sec.

  17. Off-resonance energy absorption in a linear Paul trap due to mass selective resonant quenching

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sivarajah, I.; Goodman, D. S.; Wells, J. E.

    Linear Paul traps (LPT) are used in many experimental studies such as mass spectrometry, atom-ion collisions, and ion-molecule reactions. Mass selective resonant quenching (MSRQ) is implemented in LPT either to identify a charged particle's mass or to remove unwanted ions from a controlled experimental environment. In the latter case, MSRQ can introduce undesired heating to co-trapped ions of different mass, whose secular motion is off resonance with the quenching ac field, which we call off-resonance energy absorption (OREA). We present simulations and experimental evidence that show that the OREA increases exponentially with the number of ions loaded into the trapmore » and with the amplitude of the off-resonance external ac field.« less

  18. A Novel Approach to β-delayed Neutron Spectroscopy Using the Beta-decay Paul Trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scielzo, N.D., E-mail: scielzo1@llnl.gov; Yee, R.M.; Department of Nuclear Engineering, University of California, Berkeley, CA 94720

    A new approach to β-delayed neutron spectroscopy has been demonstrated that circumvents the many limitations associated with neutron detection by instead inferring the decay branching ratios and energy spectra of the emitted neutrons by studying the nuclear recoil. Using the Beta-decay Paul Trap, fission-product ions were trapped and confined to within a 1-mm{sup 3} volume under vacuum using only electric fields. Results from recent measurements of {sup 137}I{sup +} and plans for development of a dedicated ion trap for future experiments using the intense fission fragment beams from the Californium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne National Laboratorymore » are summarized. The improved nuclear data that can be collected is needed in many fields of basic and applied science such as nuclear energy, nuclear astrophysics, and stockpile stewardship.« less

  19. Excitation of transverse dipole and quadrupole modes in a pure ion plasma in a linear Paul trap to study collective processes in intense beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gilson, Erik P.; Davidson, Ronald C.; Efthimion, Philip C.

    Transverse dipole and quadrupole modes have been excited in a one-component cesium ion plasma trapped in the Paul Trap Simulator Experiment (PTSX) in order to characterize their properties and understand the effect of their excitation on equivalent long-distance beam propagation. The PTSX device is a compact laboratory Paul trap that simulates the transverse dynamics of a long, intense charge bunch propagating through an alternating-gradient transport system by putting the physicist in the beam's frame of reference. A pair of arbitrary function generators was used to apply trapping voltage waveform perturbations with a range of frequencies and, by changing which electrodesmore » were driven with the perturbation, with either a dipole or quadrupole spatial structure. The results presented in this paper explore the dependence of the perturbation voltage's effect on the perturbation duration and amplitude. Perturbations were also applied that simulate the effect of random lattice errors that exist in an accelerator with quadrupole magnets that are misaligned or have variance in their field strength. The experimental results quantify the growth in the equivalent transverse beam emittance that occurs due to the applied noise and demonstrate that the random lattice errors interact with the trapped plasma through the plasma's internal collective modes. Coherent periodic perturbations were applied to simulate the effects of magnet errors in circular machines such as storage rings. The trapped one component plasma is strongly affected when the perturbation frequency is commensurate with a plasma mode frequency. The experimental results, which help to understand the physics of quiescent intense beam propagation over large distances, are compared with analytic models.« less

  20. Rotational dynamics of a diatomic molecular ion in a Paul trap

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashemloo, A.; Dion, C. M., E-mail: claude.dion@umu.se

    We present models for a heteronuclear diatomic molecular ion in a linear Paul trap in a rigid-rotor approximation, one purely classical and the other where the center-of-mass motion is treated classically, while rotational motion is quantized. We study the rotational dynamics and their influence on the motion of the center-of-mass, in the presence of the coupling between the permanent dipole moment of the ion and the trapping electric field. We show that the presence of the permanent dipole moment affects the trajectory of the ion and that it departs from the Mathieu equation solution found for atomic ions. For themore » case of quantum rotations, we also evidence the effect of the above-mentioned coupling on the rotational states of the ion.« less

  1. Recent Developments in Microwave Ion Clocks

    NASA Astrophysics Data System (ADS)

    Prestage, John D.; Tjoelker, Robert L.; Maleki, Lute

    We review the development of microwave-frequency standards based on trapped ions. Following two distinct paths, microwave ion clocks have evolved greatly in the last twenty years since the earliest Paul-trap-based units. Laser-cooled ion frequency standards reduce the second-order Doppler shift from ion micromotion and thermal secular motion achieving good signal-to-noise ratios via cycling transitions where as many as ~10^8 photons per second per ion may be scattered. Today, laser-cooled ion standards are based on linear Paul traps which hold ions near the node line of the trapping electric field, minimizing micromotion at the trapping-field frequency and the consequent second-order Doppler frequency shift. These quadrupole (radial) field traps tightly confine tens of ions to a crystalline single-line structure. As more ions are trapped, space charge forces some ions away from the node-line axis and the second-order Doppler effect grows larger, even at negligibly small secular temperatures. Buffer-gas-cooled clocks rely on large numbers of ions, typically ~10^7, optically pumped by a discharge lamp at a scattering rate of a few photons per second per ion. To reduce the second-order Doppler shift from space charge repulsion of ions from the trap node line, novel multipole ion traps are now being developed where ions are weakly bound with confining fields that are effectively zero through the trap interior and grow rapidly near the trap electrode ``walls''.

  2. Paul trap simulator experiment to model intense-beam propagation in alternating-gradient transport systems.

    PubMed

    Gilson, Erik P; Davidson, Ronald C; Efthimion, Philip C; Majeski, Richard

    2004-04-16

    The results presented here demonstrate that the Paul trap simulator experiment (PTSX) simulates the propagation of intense charged particle beams over distances of many kilometers through magnetic alternating-gradient (AG) transport systems by making use of the similarity between the transverse dynamics of particles in the two systems. Plasmas have been trapped that correspond to normalized intensity parameters s=omega(2)(p)(0)/2omega(2)(q)

  3. Ultrafast state detection and 2D ion crystals in a Paul trap

    NASA Astrophysics Data System (ADS)

    Ip, Michael; Ransford, Anthony; Campbell, Wesley

    2016-05-01

    Projective readout of quantum information stored in atomic qubits typically uses state-dependent CW laser-induced fluorescence. This method requires an often sophisticated imaging system to spatially filter out the background CW laser light. We present an alternative approach that instead uses simple pulse sequences from a mode-locked laser to affect the same state-dependent excitations in less than 1 ns. The resulting atomic fluorescence occurs in the dark, allowing the placement of non-imaging detectors right next to the atom to improve the qubit state detection efficiency and speed. We also study 2D Coulomb crystals of atomic ions in an oblate Paul trap. We find that crystals with hundreds of ions can be held in the trap, potentially offering an alternative to the use of Penning traps for the quantum simulation of 2D lattice spin models. We discuss the classical physics of these crystals and the metastable states that are supported in 2D. This work is supported by the US Army Research Office.

  4. Miniaturized GC/MS instrumentation for in situ measurements: micro gas chromatography coupled with miniature quadrupole array and paul ion trap mass spectrometers

    NASA Technical Reports Server (NTRS)

    Holland, P.; Chutjian, A.; Darrach, M.; Orient, O.

    2002-01-01

    Miniaturized chemical instrumentation is needed for in situ measurements in planetary exploration and other spaceflight applications where factors such as reduction in payload requirements and enhanced robustness are important. In response to this need, we are 'continuing to develop miniaturized GC/MS instrumentation which combines chemical separations by gas chromatography (GC) with mass spectrometry (MS) to provide positive identification of chemical compounds in complex mixtures of gases, such as those found in the International Space Station's cabin atmosphere. Our design approach utilizes micro gas chromatography components coupled with either a miniature quadrupole mass spectrometer array (QMSA) or compact, high-resolution Paul ion trap.

  5. Active stabilization of ion trap radiofrequency potentials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, K. G.; Wong-Campos, J. D.; Restelli, A.

    2016-05-15

    We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a radiofrequency (rf) Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscillation frequency to be better than 10 Hz or 10 ppm. This represents a suppression of ambient noise on the rf circuit by 34 dB. This technique could impact the sensitivity of ion trap mass spectrometry and the fidelity of quantum operations in ion trap quantum information applications.

  6. Dynamics and control of fast ion crystal splitting in segmented Paul traps (Open Access, Publisher’s Version)

    DTIC Science & Technology

    2014-07-09

    operations, in addition to laser - or microwave-driven logic gates. Essential shuttling operations are splitting and merging of linear ion crystals. It is...from stray charges, laser induced charging of the trap [19], trap geometry imperfections or residual ponderomotive forces along the trap axis. The...transfer expressed as the mean phonon number Δ ω¯ = n E / f . We distinguish several regimes of laser –ion interaction: (i) if the vibrational

  7. Ion-trajectory analysis for micromotion minimization and the measurement of small forces

    NASA Astrophysics Data System (ADS)

    Gloger, Timm F.; Kaufmann, Peter; Kaufmann, Delia; Baig, M. Tanveer; Collath, Thomas; Johanning, Michael; Wunderlich, Christof

    2015-10-01

    For experiments with ions confined in a Paul trap, minimization of micromotion is often essential. In order to diagnose and compensate micromotion we have implemented a method that allows for finding the position of the radio-frequency (rf) null reliably and efficiently, in principle, without any variation of direct current (dc) voltages. We apply a trap modulation technique and focus-scanning imaging to extract three-dimensional ion positions for various rf drive powers and analyze the power dependence of the equilibrium position of the trapped ion. In contrast to commonly used methods, the search algorithm directly makes use of a physical effect as opposed to efficient numerical minimization in a high-dimensional parameter space. Using this method we achieve a compensation of the residual electric field that causes excess micromotion in the radial plane of a linear Paul trap down to 0.09 Vm-1 . Additionally, the precise position determination of a single harmonically trapped ion employed here can also be utilized for the detection of small forces. This is demonstrated by determining light pressure forces with a precision of 135 yN. As the method is based on imaging only, it can be applied to several ions simultaneously and is independent of laser direction and thus well suited to be used with, for example, surface-electrode traps.

  8. Precise positioning of an ion in an integrated Paul trap-cavity system using radiofrequency signals

    NASA Astrophysics Data System (ADS)

    Kassa, Ezra; Takahashi, Hiroki; Christoforou, Costas; Keller, Matthias

    2018-03-01

    We report a novel miniature Paul ion trap design with an integrated optical fibre cavity which can serve as a building block for a fibre-linked quantum network. In such cavity quantum electrodynamic set-ups, the optimal coupling of the ions to the cavity mode is of vital importance and this is achieved by moving the ion relative to the cavity mode. The trap presented herein features an endcap-style design complemented with extra electrodes on which additional radiofrequency voltages are applied to fully control the pseudopotential minimum in three dimensions. This method lifts the need to use three-dimensional translation stages for moving the fibre cavity with respect to the ion and achieves high integrability, mechanical rigidity and scalability. Not based on modifying the capacitive load of the trap, this method leads to precise control of the pseudopotential minimum allowing the ion to be moved with precisions limited only by the ion's position spread. We demonstrate this by coupling the ion to the fibre cavity and probing the cavity mode profile.

  9. An apparatus for immersing trapped ions into an ultracold gas of neutral atoms

    NASA Astrophysics Data System (ADS)

    Schmid, Stefan; Härter, Arne; Frisch, Albert; Hoinka, Sascha; Denschlag, Johannes Hecker

    2012-05-01

    We describe a hybrid vacuum system in which a single ion or a well-defined small number of trapped ions (in our case Ba+ or Rb+) can be immersed into a cloud of ultracold neutral atoms (in our case Rb). This apparatus allows for the study of collisions and interactions between atoms and ions in the ultracold regime. Our setup is a combination of a Bose-Einstein condensation apparatus and a linear Paul trap. The main design feature of the apparatus is to first separate the production locations for the ion and the ultracold atoms and then to bring the two species together. This scheme has advantages in terms of stability and available access to the region where the atom-ion collision experiments are carried out. The ion and the atoms are brought together using a moving one-dimensional optical lattice transport which vertically lifts the atomic sample over a distance of 30 cm from its production chamber into the center of the Paul trap in another chamber. We present techniques to detect and control the relative position between the ion and the atom cloud.

  10. The use of cosmic-ray muons in the energy calibration of the Beta-decay Paul Trap silicon-detector array

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hirsh, T. Y.; Perez Galvan, A.; Burkey, M.

    This article presents an approach to calibrate the energy response of double-sided silicon strip detectors (DSSDs) for low-energy nuclear-science experiments by utilizing cosmic-ray muons. For the 1-mm-thick detectors used with the Beta-decay Paul Trap, the minimum-ionizing peak from these muons provides a stable and time-independent in situ calibration point at around 300 keV, which supplements the calibration data obtained above 3 MeV from sources. The muon-data calibration is achieved by comparing experimental spectra with detailed Monte Carlo simulations performed using GEANT4 and CRY codes. This additional information constrains the calibration at lower energies, resulting in improvements in quality and accuracy.

  11. The use of cosmic-ray muons in the energy calibration of the Beta-decay Paul Trap silicon-detector array

    NASA Astrophysics Data System (ADS)

    Hirsh, T. Y.; Pérez Gálvan, A.; Burkey, M. T.; Aprahamian, A.; Buchinger, F.; Caldwell, S.; Clark, J. A.; Gallant, A. T.; Heckmaier, E.; Levand, A. F.; Marley, S. T.; Morgan, G. E.; Nystrom, A.; Orford, R.; Savard, G.; Scielzo, N. D.; Segel, R.; Sharma, K. S.; Siegl, K.; Wang, B. S.

    2018-04-01

    This article presents an approach to calibrate the energy response of double-sided silicon strip detectors (DSSDs) for low-energy nuclear-science experiments by utilizing cosmic-ray muons. For the 1-mm-thick detectors used with the Beta-decay Paul Trap, the minimum-ionizing peak from these muons provides a stable and time-independent in situ calibration point at around 300 keV, which supplements the calibration data obtained above 3 MeV from α sources. The muon-data calibration is achieved by comparing experimental spectra with detailed Monte Carlo simulations performed using GEANT4 and CRY codes. This additional information constrains the calibration at lower energies, resulting in improvements in quality and accuracy.

  12. Generalized Dicke Nonequilibrium Dynamics in Trapped Ions

    NASA Astrophysics Data System (ADS)

    Genway, Sam; Li, Weibin; Ates, Cenap; Lanyon, Benjamin P.; Lesanovsky, Igor

    2014-01-01

    We explore trapped ions as a setting to investigate nonequilibrium phases in a generalized Dicke model of dissipative spins coupled to phonon modes. We find a rich dynamical phase diagram including superradiantlike regimes, dynamical phase coexistence, and phonon-lasing behavior. A particular advantage of trapped ions is that these phases and transitions among them can be probed in situ through fluorescence. We demonstrate that the main physical insights are captured by a minimal model and consider an experimental realization with Ca+ ions trapped in a linear Paul trap with a dressing scheme to create effective two-level systems with a tunable dissipation rate.

  13. Integrated Visible Photonics for Trapped-Ion Quantum Computing

    DTIC Science & Technology

    2017-06-10

    necessarily reflect the views of the Department of Defense. Abstract- A scalable trapped-ion-based quantum - computing architecture requires the... Quantum Computing Dave Kharas, Cheryl Sorace-Agaskar, Suraj Bramhavar, William Loh, Jeremy M. Sage, Paul W. Juodawlkis, and John...coherence times, strong coulomb interactions, and optical addressability, hold great promise for implementation of practical quantum information

  14. Stability of an aqueous quadrupole micro-trap

    DOE PAGES

    Park, Jae Hyun; Krstić, Predrag S.

    2012-03-30

    Recently demonstrated functionality of an aqueous quadrupole micro- or nano-trap opens a new avenue for applications of the Paul traps, like is confinement of a charged biomolecule which requires water environment for its chemical stability. Besides strong viscosity forces, motion of a charged particle in the aqueous trap is subject to dielectrophoretic and electrophoretic forces. In this study, we describe the general conditions for stability of a charged particle in an aqueous quadrupole trap. We find that for the typical micro-trap parameters, effects of both dielectrophoresis and electrophoresis significantly influence the trap stability. In particular, the aqueous quadrupole trap couldmore » play of a role of a synthetic virtual nanopore for the 3rd generation of DNA sequencing technology.« less

  15. Thermometry of levitated nanoparticles in a hybrid electro-optical trap

    NASA Astrophysics Data System (ADS)

    Aranas, E. B.; Fonseca, P. Z. G.; Barker, P. F.; Monteiro, T. S.

    2017-03-01

    There have been recent rapid developments in stable trapping of levitated nanoparticles in high vacuum. Cooling of nanoparticles, from phonon occupancies of 107 down to ≃ 100{--}1000 phonons, have already been achieved by several groups. Prospects for quantum ground-state cooling seem extremely promising. Cavity-cooling without added stabilisation by feedback cooling remains challenging, but trapping at high vacuum in a cavity is now possible through the addition of a Paul trap. However, the Paul trap has been found to qualitatively modify the cavity output spectrum, with the latter acquiring an atypical ‘split-sideband’ structure, of different form from the displacement spectrum, and which depends on N, the optical well at which the particle localises. In the present work we investigate the N-dependence of the dynamics, in particular with respect to thermometry: we show that in strong cooling regions N≳ 100, the temperature may still be reliably inferred from the cavity output spectra. We also explain the N-dependence of the mechanical frequencies and optomechanical coupling showing that these may be accurately estimated. We present a simple ‘fast-cavity’ model for the cavity output and test all our findings against full numerical solutions of the nonlinear stochastic equations of motion for the system.

  16. Microfluidic droplet trapping array as nanoliter reactors for gas-liquid chemical reaction.

    PubMed

    Zhang, Qingquan; Zeng, Shaojiang; Qin, Jianhua; Lin, Bingcheng

    2009-09-01

    This article presents a simple method for trapping arrays of droplets relying on the designed microstructures of the microfluidic device, and this has been successfully used for parallel gas-liquid chemical reaction. In this approach, the trapping structure is composed of main channel, lateral channel and trapping region. Under a negative pressure, array droplets can be generated and trapped in the microstructure simultaneously, without the use of surfactant and the precise control of the flow velocity. By using a multi-layer microdevice containing the microstructures, single (pH gradient) and multiple gas-liquid reactions (metal ion-NH3 complex reaction) can be performed in array droplets through the transmembrane diffusion of the gas. The droplets with quantitative concentration gradient can be formed by only replacing the specific membrane. The established method is simple, robust and easy to operate, demonstrating the potential of this device for droplet-based high-throughput screening.

  17. Measuring the charge density of a tapered optical fiber using trapped microparticles.

    PubMed

    Kamitani, Kazuhiko; Muranaka, Takuya; Takashima, Hideaki; Fujiwara, Masazumi; Tanaka, Utako; Takeuchi, Shigeki; Urabe, Shinji

    2016-03-07

    We report the measurements of charge density of tapered optical fibers using charged particles confined in a linear Paul trap at ambient pressure. A tapered optical fiber is placed across the trap axis at a right angle, and polystyrene microparticles are trapped along the trap axis. The distance between the equilibrium position of a positively charged particle and the tapered fiber is used to estimate the amount of charge per unit length of the fiber without knowing the amount of charge of the trapped particle. The charge per unit length of a tapered fiber with a diameter of 1.6 μm was measured to be 2-1+3×10 -11 C/m.

  18. Squeezed coherent states of motion for ions confined in quadrupole and octupole ion traps

    NASA Astrophysics Data System (ADS)

    Mihalcea, Bogdan M.

    2018-01-01

    Quasiclassical dynamics of trapped ions is characterized by applying the time dependent variational principle (TDVP) on coherent state orbits, in case of quadrupole and octupole combined (Paul and Penning) or radiofrequency (RF) traps. A dequantization algorithm is proposed, by which the classical Hamilton (energy) function associated to the system results as the expectation value of the quantum Hamiltonian on squeezed coherent states. We develop such method and particularize the quantum Hamiltonian for both combined and RF nonlinear traps, that exhibit axial symmetry. We also build the classical Hamiltonian functions for the particular traps we considered, and find the classical equations of motion.

  19. Intrinsic anharmonic effects on the phonon frequencies and effective spin-spin interactions in a quantum simulator made from trapped ions in a linear Paul trap

    NASA Astrophysics Data System (ADS)

    McAneny, M.; Freericks, J. K.

    2014-11-01

    The Coulomb repulsion between ions in a linear Paul trap gives rise to anharmonic terms in the potential energy when expanded about the equilibrium positions. We examine the effect of these anharmonic terms on the accuracy of a quantum simulator made from trapped ions. To be concrete, we consider a linear chain of Yb171+ ions stabilized close to the zigzag transition. We find that for typical experimental temperatures, frequencies change by no more than a factor of 0.01 % due to the anharmonic couplings. Furthermore, shifts in the effective spin-spin interactions (driven by a spin-dependent optical dipole force) are also, in general, less than 0.01 % for detunings to the blue of the transverse center-of-mass frequency. However, detuning the spin interactions near other frequencies can lead to non-negligible anharmonic contributions to the effective spin-spin interactions. We also examine an odd behavior exhibited by the harmonic spin-spin interactions for a range of intermediate detunings, where nearest-neighbor spins with a larger spatial separation on the ion chain interact more strongly than nearest neighbors with a smaller spatial separation.

  20. Rydberg Excitation of a Single Trapped Ion.

    PubMed

    Feldker, T; Bachor, P; Stappel, M; Kolbe, D; Gerritsma, R; Walz, J; Schmidt-Kaler, F

    2015-10-23

    We demonstrate excitation of a single trapped cold (40)Ca(+) ion to Rydberg levels by laser radiation in the vacuum ultraviolet at a wavelength of 122 nm. Observed resonances are identified as 3d(2)D(3/2) to 51F, 52F and 3d(2)D(5/2) to 64F. We model the line shape and our results imply a large state-dependent coupling to the trapping potential. Rydberg ions are of great interest for future applications in quantum computing and simulation, in which large dipolar interactions are combined with the superb experimental control offered by Paul traps.

  1. Multipole electrodynamic ion trap geometries for microparticle confinement under standard ambient temperature and pressure conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mihalcea, Bogdan M., E-mail: bogdan.mihalcea@inflpr.ro; Vişan, Gina T.; Ganciu, Mihai

    2016-03-21

    Trapping of microparticles and aerosols is of great interest for physics and chemistry. We report microparticle trapping in case of multipole linear Paul trap geometries, operating under standard ambient temperature and pressure conditions. An 8- and 12-electrode linear trap geometries have been designed and tested with an aim to achieve trapping for larger number of particles and to study microparticle dynamical stability in electrodynamic fields. We report emergence of planar and volume ordered structures of microparticles, depending on the a.c. trapping frequency and particle specific charge ratio. The electric potential within the trap is mapped using the electrolytic tank method.more » Particle dynamics is simulated using a stochastic Langevin equation. We emphasize extended regions of stable trapping with respect to quadrupole traps, as well as good agreement between experiment and numerical simulations.« less

  2. Recoil ions from the β decay of 134Sb confined in a Paul trap

    NASA Astrophysics Data System (ADS)

    Siegl, K.; Scielzo, N. D.; Czeszumska, A.; Clark, J. A.; Savard, G.; Aprahamian, A.; Caldwell, S. A.; Alan, B. S.; Burkey, M. T.; Chiara, C. J.; Greene, J. P.; Harker, J.; Marley, S. T.; Morgan, G. E.; Munson, J. M.; Norman, E. B.; Orford, R.; Padgett, S.; Galván, A. Perez; Sharma, K. S.; Strauss, S. Y.

    2018-03-01

    The low-energy recoiling ions from the β decay of 134Sb were studied by using the Beta-decay Paul Trap. Using this apparatus, singly charged ions were suspended in vacuum at the center of a detector array used to detect emitted β particles, γ rays, and recoil ions in coincidence. The recoil ions emerge from the trap with negligible scattering, allowing β -decay properties and the charge-state distribution of the daughter ions to be determined from the β -ion coincidences. First-forbidden β -decay theory predicts a β -ν correlation coefficient of nearly unity for the 0- to 0+ transition from the ground state of 134Sb to the ground state of 134Te. Although this transition was expected to have a nearly 100% branching ratio, an additional 17.2(52)% of the β -decay strength must populate high-lying excited states to obtain an angular correlation consistent with unity. The extracted charge-state distribution of the recoiling ions was compared with existing β -decay results and the average charge state was found to be consistent with the results from lighter nuclei.

  3. Aharonov-Bohm effect in the tunnelling of a quantum rotor in a linear Paul trap.

    PubMed

    Noguchi, Atsushi; Shikano, Yutaka; Toyoda, Kenji; Urabe, Shinji

    2014-05-13

    Quantum tunnelling is a common fundamental quantum mechanical phenomenon that originates from the wave-like characteristics of quantum particles. Although the quantum tunnelling effect was first observed 85 years ago, some questions regarding the dynamics of quantum tunnelling remain unresolved. Here we realize a quantum tunnelling system using two-dimensional ionic structures in a linear Paul trap. We demonstrate that the charged particles in this quantum tunnelling system are coupled to the vector potential of a magnetic field throughout the entire process, even during quantum tunnelling, as indicated by the manifestation of the Aharonov-Bohm effect in this system. The tunnelling rate of the structures periodically depends on the strength of the magnetic field, whose period is the same as the magnetic flux quantum φ0 through the rotor [(0.99 ± 0.07) × φ0].

  4. Deceleration, precooling, and multi-pass stopping of highly charged ions in Be{sup +} Coulomb crystals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schmöger, L., E-mail: lisa.schmoeger@mpi-hd.mpg.de; Schwarz, M.; Versolato, O. O.

    2015-10-15

    Preparing highly charged ions (HCIs) in a cold and strongly localized state is of particular interest for frequency metrology and tests of possible spatial and temporal variations of the fine structure constant. Our versatile preparation technique is based on the generic modular combination of a pulsed ion source with a cryogenic linear Paul trap. Both instruments are connected by a compact beamline with deceleration and precooling properties. We present its design and commissioning experiments regarding these two functionalities. A pulsed buncher tube allows for the deceleration and longitudinal phase-space compression of the ion pulses. External injection of slow HCIs, specificallymore » Ar{sup 13+}, into the linear Paul trap and their subsequent retrapping in the absence of sympathetic cooling is demonstrated. The latter proved to be a necessary prerequisite for the multi-pass stopping of HCIs in continuously laser-cooled Be{sup +} Coulomb crystals.« less

  5. Nuclear data for r-process models from ion trap measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clark, Jason, E-mail: jclark@anl.gov

    2016-06-21

    To truly understand how elements are created in the universe via the astrophysical r process, accurate nuclear data are required. Historically, the isotopes involved in the r process have been difficult to access for study, but the development of new facilities and measurement techniques have put many of the r-process isotopes within reach. This paper will discuss the new CARIBU facility at Argonne National Laboratory and two pieces of experimental equipment, the Beta-decay Paul Trap and the Canadian Penning Trap, that will dramatically increase the nuclear data available for models of the astrophysical r process.

  6. Electrofluidics in Micro/Nanofluidic Systems

    NASA Astrophysics Data System (ADS)

    Guan, Weihua

    This work presents the efforts to study the electrofluidics, with a focus on the electric field - matter interactions in microfluidic and nanofluidic systems for lab-on-a-chip applications. The field of electrofluidics integrates the multidisciplinary knowledge in silicon technology, solid and soft condensed matter physics, fluidics, electrochemistry, and electronics. The fundamental understanding of electrofluidics in engineered micro and nano structures opens up wide opportunities for biomedical sensing and actuation devices integrated on a single chip. Using spatial and temporal properties of electric fields in top-down engineered micro/nana structures, we successfully demonstrated the precise control over a single macro-ion and a collective group of ions in aqueous solutions. In the manipulation of a single macro-ion, we revisited the long-time overlooked AC electrophoretic (ACEP) phenomena. We proved that the widely held notion of vanishing electrophoretic (EP) effects in AC fields does not apply to spatially non-uniform electric fields. In contrast to dielectrophoretic (DEP) traps, ACEP traps favor the downscaling of the particle size if it is sufficiently charged. We experimentally demonstrated the predicted ACEP trap by recognizing that the ACEP dynamics is equivalent to that of Paul traps working in an aqueous solution. Since all Paul traps realized so far have only been operated in vacuum or gaseous phase, our experimental effort represents the world's first aqueous Paul trap device. In the manipulation of a collective group of ions, we demonstrated that the ion transport in nanochannels can be directly gated by DC electric fields, an impossible property in microscale geometries. Successful fabrication techniques were developed to create the nanochannel structures with gating ability. Using the gated nanochannel structures, we demonstrated a field effect reconfigurable nanofluidic diode, whose forward/reverse direction as well as the rectification degree can be significantly modulated. We also demonstrated a solid-state protocell, whose ion selectivity and membrane potential can be modulated by external electric field. Moreover, by recognizing the key role played by the surface charge density in electrofluidic gating of nanochannels, a low-cost, off-chip extended gate field effect transistor (FET) structure to measure the surface charges at the dielectric-electrolyte interface is demonstrated. This technique simplifies and accelerates the process of dielectric selection for effective electrofluidic gating.

  7. Isothermal relaxation current and microstructure changes of thermally aged polyester films impregnated by epoxy resin

    NASA Astrophysics Data System (ADS)

    Jiang, Xiongwei; Sun, Potao; Peng, Qingjun; Sima, Wenxia

    2018-01-01

    In this study, to understand the effect of thermal aging on polymer films degradation, specimens of polyester films impregnated by epoxy resin with different thermal aging temperatures (80 and 130 °C) and aging times (500, 1600, 2400 and 3000 h) are prepared, then charge de-trapping properties of specimens are investigated via the isothermal relaxation current (IRC) measurement, the distributions of trap level and its corresponding density are obtained based on the modified IRC model. It is found that the deep trap density increases remarkably at the beginning of thermal aging (before 1600 h), but it decreases obviously as the aging degree increases. At elevated aging temperature and, in particular considering the presence of air gap between two-layer insulation, the peak densities of deep traps decrease more significant in the late period of aging. It can be concluded that it is the released energy from de-trapping process leads to the fast degradation of insulation. Moreover, after thermal aging, the microstructure changes of crystallinity and molecular structures are analyzed via the x-ray diffraction experiment and Fourier transform infrared spectrometer. The results indicate that the variation of the deep trap density is closely linked with the changes of microstructure, a larger interface of crystalline/amorphous phase, more defects and broken chains caused by thermal aging form higher deep trap density stored in the samples.

  8. Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps

    PubMed Central

    Hong, Seokjun; Lee, Minjae; Kwon, Yeong-Dae; Cho, Dong-il "Dan"; Kim, Taehyun

    2017-01-01

    Ions trapped in a quadrupole Paul trap have been considered one of the strong physical candidates to implement quantum information processing. This is due to their long coherence time and their capability to manipulate and detect individual quantum bits (qubits). In more recent years, microfabricated surface ion traps have received more attention for large-scale integrated qubit platforms. This paper presents a microfabrication methodology for ion traps using micro-electro-mechanical system (MEMS) technology, including the fabrication method for a 14 µm-thick dielectric layer and metal overhang structures atop the dielectric layer. In addition, an experimental procedure for trapping ytterbium (Yb) ions of isotope 174 (174Yb+) using 369.5 nm, 399 nm, and 935 nm diode lasers is described. These methodologies and procedures involve many scientific and engineering disciplines, and this paper first presents the detailed experimental procedures. The methods discussed in this paper can easily be extended to the trapping of Yb ions of isotope 171 (171Yb+) and to the manipulation of qubits. PMID:28872137

  9. New perspectives in laser analytics: Resonance-enhanced multiphoton ionization in a Paul ion trap combined with a time-of-flight mass spectrometer

    NASA Astrophysics Data System (ADS)

    Bisling, Peter; Heger, Hans Jörg; Michaelis, Walfried; Weitkamp, Claus; Zobel, Harald

    1995-04-01

    A new laser analytical device has been developed that is based on resonance-enhanced multiphoton ionization in the very center of a radio-frequency quadrupole ion trap. Applications in speciation anlaysis of biological and enviromental samples and in materials science will all benefit from laser-optical selectivity in the resonance excitation process, combined with mass-spectropic sensivity which is further enhanced by the ion accumulation and storage capability.

  10. Nanoscale microstructure effects on hydrogen behavior in rapidly solidified aluminum alloys

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tashlykova-Bushkevich, Iya I.

    2015-12-31

    The present work summarizes recent progress in the investigation of nanoscale microstructure effects on hydrogen behavior in rapidly solidified aluminum alloys foils produced at exceptionally high cooling rates. We focus here on the potential of modification of hydrogen desorption kinetics in respect to weak and strong trapping sites that could serve as hydrogen sinks in Al materials. It is shown that it is important to elucidate the surface microstructure of the Al alloy foils at the submicrometer scale because rapidly solidified microstructural features affect hydrogen trapping at nanostructured defects. We discuss the profound influence of solute atoms on hydrogen−lattice defectmore » interactions in the alloys. with emphasis on role of vacancies in hydrogen evolution; both rapidly solidified pure Al and conventionally processed aluminum samples are considered.« less

  11. Direct observation of individual hydrogen atoms at trapping sites in a ferritic steel

    NASA Astrophysics Data System (ADS)

    Chen, Y.-S.; Haley, D.; Gerstl, S. S. A.; London, A. J.; Sweeney, F.; Wepf, R. A.; Rainforth, W. M.; Bagot, P. A. J.; Moody, M. P.

    2017-03-01

    The design of atomic-scale microstructural traps to limit the diffusion of hydrogen is one key strategy in the development of hydrogen-embrittlement-resistant materials. In the case of bearing steels, an effective trapping mechanism may be the incorporation of finely dispersed V-Mo-Nb carbides in a ferrite matrix. First, we charged a ferritic steel with deuterium by means of electrolytic loading to achieve a high hydrogen concentration. We then immobilized it in the microstructure with a cryogenic transfer protocol before atom probe tomography (APT) analysis. Using APT, we show trapping of hydrogen within the core of these carbides with quantitative composition profiles. Furthermore, with this method the experiment can be feasibly replicated in any APT-equipped laboratory by using a simple cold chain.

  12. Integrated fiber-mirror ion trap for strong ion-cavity coupling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brandstätter, B., E-mail: birgit.brandstaetter@uibk.ac.at; Schüppert, K.; Casabone, B.

    2013-12-15

    We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvaturemore » and ellipticities of the fiber mirrors. From finesse measurements, we infer a single-atom cooperativity of up to 12 for FFPCs longer than 200 μm in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We characterize the birefringence of our fiber mirrors, finding that careful fiber-mirror selection enables us to construct FFPCs with degenerate polarization modes. As FFPCs are novel devices, we describe procedures developed for handling, aligning, and cleaning them. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. X-ray photoelectron spectroscopy measurements indicate that these losses may be attributable to oxygen depletion in the mirror coating. Special design considerations enable us to introduce a FFPC into a trapped ion setup. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate distortions of the potential due to the fibers. Home-built fiber feedthroughs connect the FFPC to external optics, and an integrated nanopositioning system affords the possibility of retracting or realigning the cavity without breaking vacuum.« less

  13. Protein and peptide cross sections and mass spectra in an electrostatic ion beam trap

    NASA Astrophysics Data System (ADS)

    Fradkin, Z.; Strasser, D.; Heber, O.; Rappaport, M. L.; Sharon, M.; Thomson, B. A.; Rahinov, I.; Toker, Y.; Zajfman, D.

    2017-05-01

    Among the advantages of an electrostatic ion beam trap (EIBT), which is based on purely electrostatic fields, are mass-unlimited trapping and ease of operation. We have developed a new system that couples an electrospray ion source to an EIBT. Between the source and EIBT there is a Paul trap in which the ions are accumulated before being extracted and accelerated. After the ion bunch has entered the EIBT, the ions are trapped by rapidly raising the voltages on the entrance mirror. The oscillations of the bunch are detected by amplifying the charge induced on a pickup ring in the center of the trap, the ion mass being directly proportional to the square of the oscillation period. The trapping of biomolecules in the RF-bunching mode of the EIBT is used for measurement of mass spectra and collision cross sections. Coalescence of bunches of ions of nearby mass in the self-bunching mode is also demonstrated.

  14. Beta-Delayed Neutron Spectroscopy with Trapped Fission Products

    NASA Astrophysics Data System (ADS)

    Czeszumska, A.; Scielzo, N. D.; Norman, E. B.; Savard, G.; Aprahamian, A.; Burkey, M.; Caldwell, S. A.; Chiara, C. J.; Clark, J. A.; Harker, J.; Marley, S. T.; Morgan, G.; Orford, R.; Padgett, S.; Perez Galvan, A.; Segel, R. E.; Sharma, K. S.; Siegl, K.; Strauss, S.; Yee, R. M.

    2014-09-01

    Characterizing β-delayed neutron emission (βn) is of importance in reactor safety modeling, understanding of r-process nucleosynthesis, and nuclear structure studies. A newly developed technique enables a reliable measurement of βn branching ratios and neutron energy spectra without directly detecting neutrons. Ions of interest are loaded into a Paul trap surrounded by an array of radiation detectors. Upon decay, recoiling daughter nuclei and emitted particles emerge from the center of the trap with minimal scattering. The neutron energy is then determined from the time-of-flight, and hence momentum, of the recoiling ions. I will explain the details of the technique, and present the results from the most recent experimental campaign at the CARIBU facility at Argonne National Laboratory. Characterizing β-delayed neutron emission (βn) is of importance in reactor safety modeling, understanding of r-process nucleosynthesis, and nuclear structure studies. A newly developed technique enables a reliable measurement of βn branching ratios and neutron energy spectra without directly detecting neutrons. Ions of interest are loaded into a Paul trap surrounded by an array of radiation detectors. Upon decay, recoiling daughter nuclei and emitted particles emerge from the center of the trap with minimal scattering. The neutron energy is then determined from the time-of-flight, and hence momentum, of the recoiling ions. I will explain the details of the technique, and present the results from the most recent experimental campaign at the CARIBU facility at Argonne National Laboratory. This work was supported under contracts DE-NA0000979 (NSSC), DE-AC52-07NA27344 (LLNL), DE-AC02-06CH11357 (ANL), DE-FG02-94ER40834 (U. Maryland), DE-FG02-98ER41086 (Northwestern U.), NSERC, Canada, under Application No. 216974, and DHS.

  15. Millikelvin cooling of the center-of-mass motion of a levitated nanoparticle

    NASA Astrophysics Data System (ADS)

    Bullier, Nathanaël. P.; Pontin, Antonio; Barker, Peter F.

    2017-08-01

    Cavity optomechanics has been used to cool the center-of-mass motion of levitated nanospheres to millikelvin temperatures. Trapping the particle in the cavity field enables high mechanical frequencies bringing the system close to the resolved-sideband regime. Here we describe a Paul trap constructed from a printed circuit board that is small enough to fit inside the optical cavity and which should enable an accurate positioning of the particle inside the cavity field. This will increase the optical damping and therefore reduce the final temperature by at least one order of magnitude. Simulations of the potential inside the trap enable us to estimate the charge- to-mass ratio of trapped particles by measuring the secular frequencies as a function of the trap parameters. Lastly, we show the importance of reducing laser noise to reach lower temperatures and higher sensitivity in the phase-sensitive readout.

  16. Effect of Phosphate-Buffered Solution Corrosion on the Ratcheting Fatigue Behavior of a Duplex Mg-Li-Al Alloy

    NASA Astrophysics Data System (ADS)

    Yuan, Xin; Yu, Dunji; Gao, Li-Lan; Gao, Hong

    2016-05-01

    This work reports the uniaxial ratcheting and fatigue behavior of a duplex Mg-Li-Al alloy under the influence of phosphate-buffered solution corrosion. Microstructural observations reveal pitting and filament corrosion defects, which impair the load-bearing capacity of the alloy and cause stress concentration, thus leading to an accelerated accumulation of ratcheting strain and shortened fatigue life under the same nominal loading conditions. Comparing Smith model, Smith-Watson-Topper model, and Paul-Sivaprasad-Dhar model, a ratcheting fatigue life prediction model based on the Broberg damage rule and the Paul-Sivaprasad-Dhar model was proposed, and the model yielded a superior prediction for the studied magnesium alloy.

  17. Measurement of the trapping and detrapping properties of polymers in relation with their microstructure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vallayer, B.; Hourquebie, P.; Marsacq, D.

    1996-12-31

    In the field of Space Charge Physics, the role of electrical traps on space charge behavior and therefore on the breakdown properties has been now well-established. However, the traps in polymers are very difficult to define compared to the case of ceramics for which a lot of studies have been performed. A new specific method for measuring the trapping and detrapping properties of dielectric materials has been developed. This method allows to characterize the electrostatic state of an insulating sample after irradiation by a high energy electron beam. The authors discuss the basis of the method and its general possibilitiesmore » to measure the breakdown relevant parameters as the secondary electron yield for instance. Moreover, the method has been used on several polymers as HDPE and LDPE. The difference of trapping properties between those materials can be explained by microstructure evolutions (crystallinity ratio) due to a difference of the branching rate. This difference of trapping and detrapping properties of these two polymers could be connected to the breakdown behavior of the two materials which is known to be very different.« less

  18. Crystal step edges can trap electrons on the surfaces of n-type organic semiconductors.

    PubMed

    He, Tao; Wu, Yanfei; D'Avino, Gabriele; Schmidt, Elliot; Stolte, Matthias; Cornil, Jérôme; Beljonne, David; Ruden, P Paul; Würthner, Frank; Frisbie, C Daniel

    2018-05-30

    Understanding relationships between microstructure and electrical transport is an important goal for the materials science of organic semiconductors. Combining high-resolution surface potential mapping by scanning Kelvin probe microscopy (SKPM) with systematic field effect transport measurements, we show that step edges can trap electrons on the surfaces of single crystal organic semiconductors. n-type organic semiconductor crystals exhibiting positive step edge surface potentials display threshold voltages that increase and carrier mobilities that decrease with increasing step density, characteristic of trapping, whereas crystals that do not have positive step edge surface potentials do not have strongly step density dependent transport. A device model and microelectrostatics calculations suggest that trapping can be intrinsic to step edges for crystals of molecules with polar substituents. The results provide a unique example of a specific microstructure-charge trapping relationship and highlight the utility of surface potential imaging in combination with transport measurements as a productive strategy for uncovering microscopic structure-property relationships in organic semiconductors.

  19. The Trapped Radiation Handbook. Change 4,

    DTIC Science & Technology

    1977-01-04

    DLSE ATT!t Technical Library CommanderAD) COBI /KPD Dat. 1, 12W5 ATTN: Hqs. 14th Aerospace Force (EVN) Space Forecasting Section ATTN: Paul Hason...ATTN: R. P. Caren, D/52-20 ATTNi Hans Wolfhard ATTNI D. C. Fisher, U/52-14 ATTNt Joel Bengston ATTN, Richard G. Johnson, Dept. 52-12 ATTN: Ernest Buer

  20. Miniaturized system of a gas chromatograph coupled with a Paul ion trap mass spectrometer

    NASA Technical Reports Server (NTRS)

    Shortt, B. J.; Darrach, M. R.; Holland, Paul M.; Chutjian, A.

    2005-01-01

    Miniature gas chromatography (GC) and miniature mass spectrometry (MS) instrumentation has been developed to identify and quantify the chemical compounds present in complex mixtures of gases. The design approach utilizes micro-GC components coupled with a Paul quadrupole ion trap (QIT) mass spectrometer. Inherent to the system are high sensitivity, good dynamic range, good QIT resolution, low GC flow-rates to minimize vacuum requirements and the need for consumables; and the use of a modular approach to adapt to volatile organic compounds dissolved in water or present in sediment. Measurements are reported on system response to gaseous species at concentrations varying over four orders of magnitude. The ability of the system to deal with complicated mixtures is demonstrated, and future improvements are discussed. The GC/QIT system described herein has a mass, volume and power that are, conservatively, one-twentieth of those of commercial off-the-shelf systems. Potential applications are to spacecraft cabin-air monitoring, robotic planetary exploration and trace-species detection for residual gas analysis and environmental monitoring.

  1. Thermal desorption spectroscopy of high fluence irradiated ultrafine and nanocrystalline tungsten: helium trapping and desorption correlated with morphology

    NASA Astrophysics Data System (ADS)

    El-Atwani, O.; Taylor, C. N.; Frishkoff, J.; Harlow, W.; Esquivel, E.; Maloy, S. A.; Taheri, M. L.

    2018-01-01

    Microstructural changes due to displacement damage and helium desorption are two phenomena that occur in tungsten plasma facing materials in fusion reactors. Nanocrystalline metals are being investigated as radiation tolerant materials that can mitigate these microstructural changes and better trap helium along their grain boundaries. Here, we investigate the performance of three tungsten grades (nanocrystalline, ultrafine and ITER grade tungsten), exposed to a high fluence of 4 keV helium at both RT and 773 K, during a thermal desorption spectroscopy (TDS) experiment. An investigation of the microstructure in pre-and post-TDS sample sets was performed. The amount of desorbed helium was shown to be highest in the ITER grade tungsten and lowest in the nanocrystalline tungsten. Correlating the desorption spectra and the microstructure (grain boundaries decorated with nanopores and crack formation) and comparing with previous literature on coarse grained tungsten samples at similar irradiation and TDS conditions, revealed the importance of grain boundaries in trapping helium and limiting helium desorption up to a high temperature of 1350 K in agreement with transmission electron microscopy studies on helium irradiated tungsten which showed preferential and large facetted bubble formation along the grain boundaries in the nanocrystalline tungsten grade.

  2. Micromanipulation and microfabrication for optical microrobotics

    NASA Astrophysics Data System (ADS)

    Palima, Darwin; Bañas, Andrew Rafael; Vizsnyiczai, Gaszton; Kelemen, Lóránd; Aabo, Thomas; Ormos, Pál.; Glückstad, Jesper

    2012-10-01

    Robotics can use optics feedback in vision-based control of intelligent robotic guidance systems. With light's miniscule momentum, shrinking robots down to the microscale regime creates opportunities for exploiting optical forces and torques in microrobotic actuation and control. Indeed, the literature on optical trapping and micromanipulation attests to the possibilities for optical microrobotics. This work presents an optical microrobotics perspective on the optical microfabrication and micromanipulation work that we performed. We designed different three-dimensional microstructures and fabricated them by two-photon polymerization. These microstructures were then handled using our biophotonics workstation (BWS) for proof-of-principle demonstrations of optical actuation, akin to 6DOF actuation of robotic micromanipulators. Furthermore, we also show an example of dynamic behavior of the trapped microstructure that can be achieved when using static traps in the BWS. This can be generalized, in the future, towards a structural shaping optimization strategy for optimally controlling microstructures to complement approaches based on lightshaping. We also show that light channeled to microfabricated, free-standing waveguides can be used not only to redirect light for targeted delivery of optical energy but can also for targeted delivery of optical force, which can serve to further extend the manipulation arms in optical robotics. Moreover, light deflection with waveguide also creates a recoil force on the waveguide, which can be exploited for controlling the optical force.

  3. Thermal desorption spectroscopy of high fluence irradiated ultrafine and nanocrystalline tungsten: helium trapping and desorption correlated with morphology

    DOE PAGES

    El-Atwani, Osman; Taylor, Chase N.; Frishkoff, James; ...

    2017-11-09

    Here, microstructural changes due to displacement damage and helium desorption are two phenomena that occur in tungsten plasma facing materials in fusion reactors. Nanocrystalline metals are being investigated as radiation tolerant materials that can mitigate these microstructural changes and better trap helium along their grain boundaries. Here, we investigate the performance of three tungsten grades (nanocrystalline, ultrafine and ITER grade tungsten), exposed to a high fluence of 4 keV helium at both RT and 773 K, during a thermal desorption spectroscopy (TDS) experiment. An investigation of the microstructure in pre-and post-TDS sample sets was performed. The amount of desorbed heliummore » was shown to be highest in the ITER grade tungsten and lowest in the nanocrystalline tungsten. Correlating the desorption spectra and the microstructure (grain boundaries decorated with nanopores and crack formation) and comparing with previous literature on coarse grained tungsten samples at similar irradiation and TDS conditions, revealed the importance of grain boundaries in trapping helium and limiting helium desorption up to a high temperature of 1350 K in agreement with transmission electron microscopy studies on helium irradiated tungsten which showed preferential and large facetted bubble formation along the grain boundaries in the nanocrystalline tungsten grade.« less

  4. Construction of microscale structures in enclosed microfluidic networks by using a magnetic beads based method.

    PubMed

    Wang, Zhenyu; Zhang, Xiaojuan; Yang, Jun; Yang, Zhong; Wan, Xiaoping; Hu, Ning; Zheng, Xiaolin

    2013-08-20

    A large number of microscale structures have been used to elaborate flowing control or complex biological and chemical reaction on microfluidic chips. However, it is still inconvenient to fabricate microstructures with different heights (or depths) on the same substrate. These kinds of microstructures can be fabricated by using the photolithography and wet-etching method step by step, but involves time-consuming design and fabrication process, as well as complicated alignment of different masters. In addition, few existing methods can be used to perform fabrication within enclosed microfluidic networks. It is also difficult to change or remove existing microstructures within these networks. In this study, a magnetic-beads-based approach is presented to build microstructures in enclosed microfluidic networks. Electromagnetic field generated by microfabricated conducting wires (coils) is used to manipulate and trap magnetic beads on the bottom surface of a microchannel. These trapped beads are accumulated to form a microscale pile with desired shape, which can adjust liquid flow, dock cells, modify surface, and do some other things as those fabricated microstructures. Once the electromagnetic field is changed, trapped beads may form new shapes or be removed by a liquid flow. Besides being used in microfabrication, this magnetic-beads-based method can be used for novel microfluidic manipulation. It has been validated by forming microscale dam structure for cell docking and modified surface for cell patterning, as well as guiding the growth of neurons. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. A highly miniaturized vacuum package for a trapped ion atomic clock

    DOE PAGES

    Schwindt, Peter D. D.; Jau, Yuan-Yu; Partner, Heather; ...

    2016-05-12

    We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm 3 in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, the packagemore » was sealed with a copper pinch-off and was then pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of 171Yb +. The fractional frequency stability of the clock was measured to be 2 × 10 -11 / τ 1/2.« less

  6. Microstructure and trapped field of YBCO bulk single-grain superconductors prepared by interior seeding

    NASA Astrophysics Data System (ADS)

    Radusovska, M.; Diko, P.; Piovarci, S.; Park, S.-D.; Jun, B.-H.; Kim, C.-J.

    2017-10-01

    The microstructural analyses of YBCO bulk single-grain superconductors grown by interior seeding with taller and shorter upper pellets have shown that a suitable upper pellet height can lower the porosity in the upper part of the sample, produce a more appropriate distribution of pinning centres in the form of Y-211 particles and suppress subgrain formation with a higher crystal misalignment in the c-growth sector (c-GS), which can lead to a higher measured trapped magnetic field and a more uniform cone of the trapped-field profile. The observed bulging of the sample surface at the c-GS can be explained by the edge melt distribution model, which shows that macroscopic mass transport to the growth sector occurs with higher growth rates.

  7. Microstructure Hierarchical Model of Competitive e+-Ps Trapping in Nanostructurized Substances: from Nanoparticle-Uniform to Nanoparticle-Biased Systems.

    PubMed

    Shpotyuk, Oleh; Ingram, Adam; Bujňáková, Zdenka; Baláž, Peter

    2017-12-01

    Microstructure hierarchical model considering the free-volume elements at the level of interacting crystallites (non-spherical approximation) and the agglomerates of these crystallites (spherical approximation) was developed to describe free-volume evolution in mechanochemically milled As 4 S 4 /ZnS composites employing positron annihilation spectroscopy in a lifetime measuring mode. Positron lifetime spectra were reconstructed from unconstrained three-term decomposition procedure and further subjected to parameterization using x3-x2-coupling decomposition algorithm. Intrinsic inhomogeneities due to coarse-grained As 4 S 4 and fine-grained ZnS nanoparticles were adequately described in terms of substitution trapping in positron and positronium (Ps) (bound positron-electron) states due to interfacial triple junctions between contacting particles and own free-volume defects in boundary compounds. Compositionally dependent nanostructurization in As 4 S 4 /ZnS nanocomposite system was imagined as conversion from o-Ps trapping sites to positron traps. The calculated trapping parameters that were shown could be useful to characterize adequately the nanospace filling in As 4 S 4 /ZnS composites.

  8. Optimization of chemical compositions in low-carbon Al-killed enamel steel produced by ultra-fast continuous annealing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dong, Futao, E-mail: dongft@sina.com; Du, Linxiu; Liu, Xianghua

    2013-10-15

    The influence of Mn,S and B contents on microstructural characteristics, mechanical properties and hydrogen trapping ability of low-carbon Al-killed enamel steel was investigated. The materials were produced and processed in a laboratory and the ultra-fast continuous annealing processing was performed using a continuous annealing simulator. It was found that increasing Mn,S contents in steel can improve its hydrogen trapping ability which is attributed by refined ferrite grains, more dispersed cementite and added MnS inclusions. Nevertheless, it deteriorates mechanical properties of steel sheet. Addition of trace boron results in both good mechanical properties and significantly improved hydrogen trapping ability. The boronmore » combined with nitrogen segregating at grain boundaries, cementite and MnS inclusions, provides higher amount of attractive hydrogen trapping sites and raises the activation energy for hydrogen desorption from them. - Highlights: • We study microstructures and properties in low-carbon Al-killed enamel steel. • Hydrogen diffusion coefficients are measured to reflect fish-scale resistance. • Manganese improves hydrogen trapping ability but decrease deep-drawing ability. • Boron improves both hydrogen trapping ability and deep-drawing ability. • Both excellent mechanical properties and fish-scale resistance can be matched.« less

  9. Controlling the polypyrrole microstructures using swollen liquid crystals as structure directing agent

    NASA Astrophysics Data System (ADS)

    Dutt, S.; Sharma, R.

    2017-10-01

    Microstructures of polypyrrole (PPy) with different morphology were synthesized using swollen liquid crystals (SLCs) as soft structure directing agents and confinement effect on the control of PPy microstructures have been thoroughly investigated. SLCs are the quaternary mixtures of aqueous phase: oil phase: surfactant: co-surfactant. Mesophases of PPy were synthesized by trapping small amount of pyrrole in the oil phase of SLCs. Spherical, fiber and rod-like microstructures of PPy were synthesized by adding ammonium persulphate (APS) as an oxidant under different synthesis conditions using SLCs. The possible mechanism for the formation of different PPy microstructures also proposed in this study.

  10. A highly miniaturized vacuum package for a trapped ion atomic clock

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schwindt, Peter D. D., E-mail: pschwin@sandia.gov; Jau, Yuan-Yu; Partner, Heather

    2016-05-15

    We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm{sup 3} in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, it wasmore » sealed with a copper pinch-off and was subsequently pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of {sup 171}Y b{sup +}. The fractional frequency stability of the clock was measured to be 2 × 10{sup −11}/τ{sup 1/2}.« less

  11. Efficient Raman sideband cooling of trapped ions to their motional ground state

    NASA Astrophysics Data System (ADS)

    Che, H.; Deng, K.; Xu, Z. T.; Yuan, W. H.; Zhang, J.; Lu, Z. H.

    2017-07-01

    Efficient cooling of trapped ions is a prerequisite for various applications of the ions in precision spectroscopy, quantum information, and coherence control. Raman sideband cooling is an effective method to cool the ions to their motional ground state. We investigate both numerically and experimentally the optimization of Raman sideband cooling strategies and propose an efficient one, which can simplify the experimental setup as well as reduce the number of cooling pulses. Several cooling schemes are tested and compared through numerical simulations. The simulation result shows that the fixed-width pulses and varied-width pulses have almost the same efficiency for both the first-order and the second-order Raman sideband cooling. The optimized strategy is verified experimentally. A single 25Mg+ ion is trapped in a linear Paul trap and Raman sideband cooled, and the achieved average vibrational quantum numbers under different cooling strategies are evaluated. A good agreement between the experimental result and the simulation result is obtained.

  12. Effects of alloying elements on thermal desorption of helium in Ni alloys

    NASA Astrophysics Data System (ADS)

    Xu, Q.; Cao, X. Z.; Sato, K.; Yoshiie, T.

    2012-12-01

    It is well known that the minor elements Si and Sn can suppress the formation of voids in Ni alloys. In the present study, to investigate the effects of Si and Sn on the retention of helium in Ni alloys, Ni, Ni-Si, and Ni-Sn alloys were irradiated by 5 keV He ions at 723 K. Thermal desorption spectroscopy (TDS) was performed at up to 1520 K, and microstructural observations were carried out to identify the helium trapping sites during the TDS analysis. Two peaks, at 1350 and 1457 K, appeared in the TDS spectrum of Ni. On the basis of the microstructural observations, the former peak was attributed to the release of trapped helium from small cavities and the latter to its release from large cavities. Small-cavity helium trapping sites were also found in the Ni-Si and Ni-Sn alloys, but no large cavities were observed in these alloys. In addition, it was found that the oversized element Sn could trap He atoms in the Ni-Sn alloy.

  13. Optically detected, single nanoparticle mass spectrometer with pre-filtered electrospray nanoparticle source

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Howder, Collin R.; Bell, David M.; Anderson, Scott L.

    2014-01-15

    An instrument designed for non-destructive mass analysis of single trapped nanoparticles is described. The heart of the instrument is a 3D quadrupole (Paul) trap constructed to give optical access to the trap center along ten directions, allowing passage of lasers for particle heating and detection, particle injection, collection of scattered or fluorescent photons for particle detection and mass analysis, and collection of particles on TEM grids for analysis, as needed. Nanoparticles are injected using an electrospray ionization (ESI) source, and conditions are described for spraying and trapping polymer particles, bare metal particles, and ligand stabilized particles with masses ranging frommore » 200 kDa to >3 GDa. Conditions appropriate to ESI and injection of different types of particles are described. The instrument is equipped with two ion guides separating the ESI source and nanoparticle trap. The first ion guide is mostly to allow desolvation and differential pumping before the particles enter the trap section of the instrument. The second is a linear quadrupole guide, which can be operated in mass selective or mass band-pass modes to limit transmission to species with mass-to-charge ratios in the range of interest. With a little experience, the design allows injection of single particles into the trap upon demand.« less

  14. New Light Alloys (Les Nouveaux Alliages Legers)

    DTIC Science & Technology

    1990-09-01

    Authors/Speakers iv Reference Introduction I by IGA P.Costa The Development of Aluminium Lithium Alloys: An Overview I by C. J.Peel The Microstructure...Magnesium Alloys 7 by DJ.Bray V 1 INTRODUCTION by Paul Costa Materials Department, Head, ONERA BP 72 F92322 Chatillon Cedex France The last fifteen years... INTRODUCTION For the last decade the aluminium industry has been redeveloping aluminium-lithium alloys for aerospace use. Whilst not new in concept or

  15. A low-drift, low-noise, multichannel dc voltage source for segmented-electrode Paul traps

    NASA Astrophysics Data System (ADS)

    Beev, Nikolai; Fenske, Julia-Aileen; Hannig, Stephan; Schmidt, Piet O.

    2017-05-01

    We present the design, construction, and characterization of a multichannel, low-drift, low-noise dc voltage source specially designed for biasing the electrodes of segmented linear Paul traps. The system produces 20 output voltage pairs having a common-mode range of 0 to +120 V with 3.7 mV/LSB (least significant bit) resolution and differential ranges of ±5 V with 150 μV/LSB or ±16 V with 610 μV/LSB resolution. All common-mode and differential voltages are independently controllable, and all pairs share the same ground reference. The measured drift of the voltages after warm-up is lower than 1 LSB peak-to-peak on the time scale of 2 h. The noise of an output voltage measured with respect to ground is <10 μVRMS within 10 Hz-100 kHz, with spectral density lower than 3 nV Hz-1/2 above 50 kHz. The performance of the system is limited by the external commercial multichannel DAC unit NI 9264, and in principle, it is possible to achieve higher stability and lower noise with the same voltage ranges. The system has a compact, modular, and scalable architecture, having all parts except for the DAC chassis housed within a single 19″ 3HE rack.

  16. Micromotion-enabled improvement of quantum logic gates with trapped ions

    NASA Astrophysics Data System (ADS)

    Bermudez, Alejandro; Schindler, Philipp; Monz, Thomas; Blatt, Rainer; Müller, Markus

    2017-11-01

    The micromotion of ion crystals confined in Paul traps is usually considered an inconvenient nuisance, and is thus typically minimized in high-precision experiments such as high-fidelity quantum gates for quantum information processing (QIP). In this work, we introduce a particular scheme where this behavior can be reversed, making micromotion beneficial for QIP. We show that using laser-driven micromotion sidebands, it is possible to engineer state-dependent dipole forces with a reduced effect of off-resonant couplings to the carrier transition. This allows one, in a certain parameter regime, to devise entangling gate schemes based on geometric phase gates with both a higher speed and a lower error, which is attractive in light of current efforts towards fault-tolerant QIP. We discuss the prospects of reaching the parameters required to observe this micromotion-enabled improvement in experiments with current and future trap designs.

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    El-Atwani, Osman; Taylor, Chase N.; Frishkoff, James

    Here, microstructural changes due to displacement damage and helium desorption are two phenomena that occur in tungsten plasma facing materials in fusion reactors. Nanocrystalline metals are being investigated as radiation tolerant materials that can mitigate these microstructural changes and better trap helium along their grain boundaries. Here, we investigate the performance of three tungsten grades (nanocrystalline, ultrafine and ITER grade tungsten), exposed to a high fluence of 4 keV helium at both RT and 773 K, during a thermal desorption spectroscopy (TDS) experiment. An investigation of the microstructure in pre-and post-TDS sample sets was performed. The amount of desorbed heliummore » was shown to be highest in the ITER grade tungsten and lowest in the nanocrystalline tungsten. Correlating the desorption spectra and the microstructure (grain boundaries decorated with nanopores and crack formation) and comparing with previous literature on coarse grained tungsten samples at similar irradiation and TDS conditions, revealed the importance of grain boundaries in trapping helium and limiting helium desorption up to a high temperature of 1350 K in agreement with transmission electron microscopy studies on helium irradiated tungsten which showed preferential and large facetted bubble formation along the grain boundaries in the nanocrystalline tungsten grade.« less

  18. Electron shakeoff following the β+ decay of +19Ne and +35Ar trapped ions

    NASA Astrophysics Data System (ADS)

    Fabian, X.; Fléchard, X.; Pons, B.; Liénard, E.; Ban, G.; Breitenfeldt, M.; Couratin, C.; Delahaye, P.; Durand, D.; Finlay, P.; Guillon, B.; Lemière, Y.; Mauger, F.; Méry, A.; Naviliat-Cuncic, O.; Porobic, T.; Quéméner, G.; Severijns, N.; Thomas, J.-C.

    2018-02-01

    The electron shakeoff of 19F and 35Cl atoms resulting from the β+ decay of +19Ne and +35Ar ions has been investigated using a Paul trap coupled to a time of flight recoil-ion spectrometer. The charge-state distributions of the recoiling daughter nuclei were compared to theoretical calculations based on the sudden approximation and accounting for subsequent Auger processes. The excellent agreement obtained for 35Cl is not reproduced in 19F. The shortcoming is attributed to the inaccuracy of the independent particle model employed to calculate the primary shakeoff probabilities in systems with rather low atomic numbers. This calls for more elaborate calculations, including explicitly the electron-electron correlations.

  19. Study of In-Trap Ion Clouds by Ion Trajectory Simulations.

    PubMed

    Zhou, Xiaoyu; Liu, Xinwei; Cao, Wenbo; Wang, Xiao; Li, Ming; Qiao, Haoxue; Ouyang, Zheng

    2018-02-01

    Gaussian distribution has been utilized to describe the global number density distribution of ion cloud in the Paul trap, which is known as the thermal equilibrium theory and widely used in theoretical modeling of ion clouds in the ion traps. Using ion trajectory simulations, however, the ion clouds can now also be treated as a dynamic ion flow field and the location-dependent features could now be characterized. This study was carried out to better understand the in-trap ion cloud properties, such as the local particle velocity and temperature. The local ion number densities were found to be heterogeneously distributed in terms of mean and distribution width; the velocity and temperature of the ion flow varied with pressure depending on the flow type of the neutral molecules; and the "quasi-static" equilibrium status can only be achieved after a certain number of collisions, for which the time period is pressure-dependent. This work provides new insights of the ion clouds that are globally stable but subjected to local rf heating and collisional cooling. Graphical Abstract ᅟ.

  20. Motion Control and Optical Interrogation of a Levitating Single Nitrogen Vacancy in Vacuum.

    PubMed

    Conangla, Gerard P; Schell, Andreas W; Rica, Raúl A; Quidant, Romain

    2018-05-24

    Levitation optomechanics exploits the unique mechanical properties of trapped nano-objects in vacuum to address some of the limitations of clamped nanomechanical resonators. In particular, its performance is foreseen to contribute to a better understanding of quantum decoherence at the mesoscopic scale as well as to lead to novel ultrasensitive sensing schemes. While most efforts have focused so far on the optical trapping of low-absorption silica particles, further opportunities arise from levitating objects with internal degrees of freedom, such as color centers. Nevertheless, inefficient heat dissipation at low pressures poses a challenge because most nano-objects, even with low-absorption materials, experience photodamage in an optical trap. Here, by using a Paul trap, we demonstrate levitation in vacuum and center-of-mass feedback cooling of a nanodiamond hosting a single nitrogen-vacancy center. The achieved level of motion control enables us to optically interrogate and characterize the emitter response. The developed platform is applicable to a wide range of other nano-objects and represents a promising step toward coupling internal and external degrees of freedom.

  1. Diversity of multinucleated giant cells by microstructures of hydroxyapatite and plasma components in extraskeletal implantation model.

    PubMed

    Morishita, Kota; Tatsukawa, Eri; Shibata, Yasuaki; Suehiro, Fumio; Kamitakahara, Masanobu; Yokoi, Taishi; Ioku, Koji; Umeda, Masahiro; Nishimura, Masahiro; Ikeda, Tohru

    2016-07-15

    Foreign body giant cells (FBGCs) and osteoclasts are multinucleated giant cells (MNGCs), both of which are formed by the fusion of macrophage-derived mononuclear cells. Osteoclasts are distinct from FBGCs due to their bone resorption ability; however, not only morphological, but also functional similarities may exist between these cells. The characterization and diversity of FBGCs that appear in an in vivo foreign body reaction currently remain incomplete. In the present study, we investigated an in vivo foreign body reaction using an extraskeletal implantation model of hydroxyapatite (HA) with different microstructures. The implantation of HA granules in rat subcutaneous tissue induced a foreign body reaction that was accompanied by various MNGCs. HA granules composed of rod-shaped particles predominantly induced cathepsin K (CTSK)-positive FBGCs, whereas HA granules composed of globular-shaped particles predominantly induced CTSK-negative FBGCs. Plasma, which was used as the binder of ceramic granules, stimulated the induction of CTSK-positive FBGCs more strongly than purified fibrin. Furthermore, the implantation of HA composed of rod-shaped particles with plasma induced tartrate-resistant acid phosphatase (TRAP)-positive MNGCs in contrast to HA composed of globular-shaped particles with purified fibrin, which predominantly induced CTSK-negative and TRAP-negative typical FBGCs. These results suggest that CTSK-positive, TRAP-positive, and CTSK- and TRAP-negative MNGCs are induced in this subcutaneous implantation model in a manner that is dependent on the microstructure of HA and presence or absence of plasma. We attempted to elucidate the mechanisms responsible for the foreign body reaction induced by the implantation of hydroxyapatite granules with different microstructures in rat subcutaneous tissue with or without plasma components as the binder of ceramic granules. By analyzing the expression of two reliable osteoclast markers, we detected tartrate-resistant acid phosphatase-positive multinucleated giant cells, cathepsin K-positive multinucleated giant cells, and tartrate-resistant acid phosphatase- and cathepsin K-negative multinucleated giant cells. The induction of tartrate-resistant acid phosphatase-positive multinucleated giant cells was plasma component-dependent while the induction of cathepsin K-positive multinucleated giant cells was influenced by the microstructure of hydroxyapatite. This is the first study to show the conditions dividing the three kinds of multinucleated giant cells in the foreign body reaction. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Effect of trap states and microstructure on charge carrier conduction mechanism through semicrystalline poly(vinyl alcohol) granular film

    NASA Astrophysics Data System (ADS)

    Das, A. K.; Bhowmik, R. N.; Meikap, A. K.

    2018-05-01

    We report a comprehensive study on hysteresis behaviour of current-voltage characteristic and impedance spectroscopy of granular semicrystalline poly(vinyl alcohol) (PVA) film. The charge carrier conduction mechanism and charge traps of granular PVA film by measuring and analyzing the temperature dependent current-voltage characteristic indicate a bi-stable electronic state in the film. A sharp transformation of charge carrier conduction mechanism from Poole-Frenkel emission to space charge limited current mechanism has been observed. An anomalous oscillatory behaviour of current has been observed due to electric pulse effect on the molecular chain of the polymer. Effect of microstructure on charge transport mechanism has been investigated from impedance spectroscopy analysis. An equivalent circuit model has been proposed to explain the result.

  3. Compost addition reduces porosity and chlordecone transfer in soil microstructure.

    PubMed

    Woignier, Thierry; Clostre, Florence; Fernandes, Paula; Rangon, Luc; Soler, Alain; Lesueur-Jannoyer, Magalie

    2016-01-01

    Chlordecone, an organochlorine insecticide, pollutes soils and contaminates crops and water resources and is biomagnified by food chains. As chlordecone is partly trapped in the soil, one possible alternative to decontamination may be to increase its containment in the soil, thereby reducing its diffusion into the environment. Containing the pesticide in the soil could be achieved by adding compost because the pollutant has an affinity for organic matter. We hypothesized that adding compost would also change soil porosity, as well as transport and containment of the pesticide. We measured the pore features and studied the nanoscale structure to assess the effect of adding compost on soil microstructure. We simulated changes in the transport properties (hydraulic conductivity and diffusion) associated with changes in porosity. During compost incubation, the clay microstructure collapsed due to capillary stresses. Simulated data showed that the hydraulic conductivity and diffusion coefficient were reduced by 95 and 70% in the clay microstructure, respectively. Reduced transport properties affected pesticide mobility and thus helped reduce its transfer from the soil to water and to the crop. We propose that the containment effect is due not only to the high affinity of chlordecone for soil organic matter but also to a trapping mechanism in the soil porosity.

  4. Hydrogen isotope trapping in Al-Cu binary alloys

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chao, Paul; Karnesky, Richard A.

    In this study, the trapping mechanisms for hydrogen isotopes in Al–X Cu (0.0 at. % < X < 3.5 at. %) alloys were investigated using thermal desorption spectroscopy (TDS), electrical conductivity, and differential scanning calorimetry. Constant heating rate TDS was used to determine microstructural trap energies and occupancies. In addition to the trapping states in pure Al reported in the literature (interstitial lattice sites, dislocations, and vacancies), a trap site due to Al–Cu intermetallic precipitates is observed. The binding energy of this precipitate trap is (18 ± 3) kJ•mol –1 (0.19 ± 0.03 eV). Typical occupancy of this trap ismore » high; for Al–2.6 at. % Cu (a Cu composition comparable to that in AA2219) charged at 200 °C with 130 MPa D 2 for 68 days, there is ca. there is 3.15×10 –7 mol D bound to the precipitate trap per mol of Al, accounting for a third of the D in the charged sample.« less

  5. Hydrogen isotope trapping in Al-Cu binary alloys

    DOE PAGES

    Chao, Paul; Karnesky, Richard A.

    2016-01-01

    In this study, the trapping mechanisms for hydrogen isotopes in Al–X Cu (0.0 at. % < X < 3.5 at. %) alloys were investigated using thermal desorption spectroscopy (TDS), electrical conductivity, and differential scanning calorimetry. Constant heating rate TDS was used to determine microstructural trap energies and occupancies. In addition to the trapping states in pure Al reported in the literature (interstitial lattice sites, dislocations, and vacancies), a trap site due to Al–Cu intermetallic precipitates is observed. The binding energy of this precipitate trap is (18 ± 3) kJ•mol –1 (0.19 ± 0.03 eV). Typical occupancy of this trap ismore » high; for Al–2.6 at. % Cu (a Cu composition comparable to that in AA2219) charged at 200 °C with 130 MPa D 2 for 68 days, there is ca. there is 3.15×10 –7 mol D bound to the precipitate trap per mol of Al, accounting for a third of the D in the charged sample.« less

  6. Ultra-broadband Tunable Resonant Light Trapping in a Two-dimensional Randomly Microstructured Plasmonic-photonic Absorber

    PubMed Central

    Liu, Zhengqi; Liu, Long; Lu, Haiyang; Zhan, Peng; Du, Wei; Wan, Mingjie; Wang, Zhenlin

    2017-01-01

    Recently, techniques involving random patterns have made it possible to control the light trapping of microstructures over broad spectral and angular ranges, which provides a powerful approach for photon management in energy efficiency technologies. Here, we demonstrate a simple method to create a wideband near-unity light absorber by introducing a dense and random pattern of metal-capped monodispersed dielectric microspheres onto an opaque metal film; the absorber works due to the excitation of multiple optical and plasmonic resonant modes. To further expand the absorption bandwidth, two different-sized metal-capped dielectric microspheres were integrated into a densely packed monolayer on a metal back-reflector. This proposed ultra-broadband plasmonic-photonic super absorber demonstrates desirable optical trapping in dielectric region and slight dispersion over a large incident angle range. Without any effort to strictly control the spatial arrangement of the resonant elements, our absorber, which is based on a simple self-assembly process, has the critical merits of high reproducibility and scalability and represents a viable strategy for efficient energy technologies. PMID:28256599

  7. The Effects of Helium Bubble Microstructure on Ductility in Annealed and HERF 21Cr-6Ni-9Mn Stainless Steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tosten, M.H.; Morgan, M.J.

    1998-01-01

    This study examined the effects of microstructure on the ambient temperature embrittlement from hydrogen isotopes and decay helium in 21Cr-6Ni-9Mn stainless steel. Hydrogen and tritium-exposed 21Cr-6Ni-9Mn stainless steel tensile samples were pulled to failure and then characterized by transmission electron microscopy (TEM) and optical microscopy. This study determined that ductility differences between annealed and high-energy-rate-forged (HERF) stainless steel containing tritium and its decay product, helium, could be related to differences in the helium bubble microstructures. The HERF microstructures were more resistant to tritium-induced embrittlement than annealed microstructures because the high number density of helium bubbles on dislocations trap tritium withinmore » the matrix and away from the grain boundaries.« less

  8. Neutral gas sympathetic cooling of an ion in a Paul trap.

    PubMed

    Chen, Kuang; Sullivan, Scott T; Hudson, Eric R

    2014-04-11

    A single ion immersed in a neutral buffer gas is studied. An analytical model is developed that gives a complete description of the dynamics and steady-state properties of the ions. An extension of this model, using techniques employed in the mathematics of economics and finance, is used to explain the recent observation of non-Maxwellian statistics for these systems. Taken together, these results offer an explanation of the long-standing issues associated with sympathetic cooling of an ion by a neutral buffer gas.

  9. Neutral Gas Sympathetic Cooling of an Ion in a Paul Trap

    NASA Astrophysics Data System (ADS)

    Chen, Kuang; Sullivan, Scott T.; Hudson, Eric R.

    2014-04-01

    A single ion immersed in a neutral buffer gas is studied. An analytical model is developed that gives a complete description of the dynamics and steady-state properties of the ions. An extension of this model, using techniques employed in the mathematics of economics and finance, is used to explain the recent observation of non-Maxwellian statistics for these systems. Taken together, these results offer an explanation of the long-standing issues associated with sympathetic cooling of an ion by a neutral buffer gas.

  10. Microstructure evolution during helium irradiation and post-irradiation annealing in a nanostructured reduced activation steel

    NASA Astrophysics Data System (ADS)

    Liu, W. B.; Ji, Y. Z.; Tan, P. K.; Zhang, C.; He, C. H.; Yang, Z. G.

    2016-10-01

    Severe plastic deformation, intense single-beam He-ion irradiation and post-irradiation annealing were performed on a nanostructured reduced activation ferritic/martensitic (RAFM) steel to investigate the effect of grain boundaries (GBs) on its microstructure evolution during these processes. A surface layer with a depth-dependent nanocrystalline (NC) microstructure was prepared in the RAFM steel using surface mechanical attrition treatment (SMAT). Microstructure evolution after helium (He) irradiation (24.8 dpa) at room temperature and after post-irradiation annealing was investigated using Transmission Electron Microscopy (TEM). Experimental observation shows that GBs play an important role during both the irradiation and the post-irradiation annealing process. He bubbles are preferentially trapped at GBs/interfaces during irradiation and cavities with large sizes are also preferentially trapped at GBs/interfaces during post-irradiation annealing, but void denuded zones (VDZs) near GBs could not be unambiguously observed. Compared with cavities at GBs and within larger grains, cavities with smaller size and higher density are found in smaller grains. The average size of cavities increases rapidly with the increase of time during post-irradiation annealing at 823 K. Cavities with a large size are observed just after annealing for 5 min, although many of the cavities with small sizes also exist after annealing for 240 min. The potential mechanism of cavity growth behavior during post-irradiation annealing is also discussed.

  11. Perspective: Electrospray photoelectron spectroscopy: From multiply-charged anions to ultracold anions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Lai-Sheng, E-mail: Lai-Sheng-Wang@brown.edu

    2015-07-28

    Electrospray ionization (ESI) has become an essential tool in chemical physics and physical chemistry for the production of novel molecular ions from solution samples for a variety of spectroscopic experiments. ESI was used to produce free multiply-charged anions (MCAs) for photoelectron spectroscopy (PES) in the late 1990 s, allowing many interesting properties of this class of exotic species to be investigated. Free MCAs are characterized by strong intramolecular Coulomb repulsions, which create a repulsive Coulomb barrier (RCB) for electron emission. The RCB endows many fascinating properties to MCAs, giving rise to meta-stable anions with negative electron binding energies. Recent developmentmore » in the PES of MCAs includes photoelectron imaging to examine the influence of the RCB on the electron emission dynamics, pump-probe experiments to examine electron tunneling through the RCB, and isomer-specific experiments by coupling PES with ion mobility for biological MCAs. The development of a cryogenically cooled Paul trap has led to much better resolved PE spectra for MCAs by creating vibrationally cold anions from the room temperature ESI source. Recent advances in coupling the cryogenic Paul trap with PE imaging have allowed high-resolution PE spectra to be obtained for singly charged anions produced by ESI. In particular, the observation of dipole-bound excited states has made it possible to conduct vibrational autodetachment spectroscopy and resonant PES, which yield much richer vibrational spectroscopic information for dipolar free radicals than traditional PES.« less

  12. Nanoporous clay with carbon sink and pesticide trapping properties

    NASA Astrophysics Data System (ADS)

    Woignier, T.; Duffours, L.; Colombel, P.; Dieudonné, P.

    2015-07-01

    A thorough understanding of the mechanisms and factors involved in the dynamics of organic carbon in soils is required to identify and enhance natural sinks for greenhouse gases. Some tropical soils, such as Andosols, have 3-6 fold higher concentrations of organic carbon than other kinds of soils containing classical clays. In the tropics, toxic pesticides permanently pollute soils and contaminate crops, water resources, and ecosystems. However, not all soils are equal in terms of pesticide contamination or in their ability to transfer pollution to the ecosystem. Andosols are generally more polluted than the other kinds of soils but, surprisingly, they retain and trap more pesticides, thereby reducing the transfer of pesticides to ecosystems, water resources, and crops. Andosols thus have interesting environmental properties in terms of soil carbon sequestration and pesticide retention. Andosols contain a nano porous clay (allophane) with unique structures and physical properties compared to more common clays; these are large pore volume, specific surface area, and a tortuous and fractal porous arrangement. The purpose of this mini review is to discuss the importance of the allophane fractal microstructure for carbon sequestration and pesticide trapping in the soil. We suggest that the tortuous microstructure (which resembles a labyrinths) of allophane aggregates and the associated low accessibility partly explain the poor availability of soil organic matter and of any pesticides trapped in andosols.

  13. Study of Nonlinear Dynamics of Intense Charged Particle Beams in the Paul Trap Simulator Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Hua

    The Paul Trap Simulator Experiment (PTSX) is a compact laboratory device that simulates the nonlinear dynamics of intense charged particle beams propagating over a large distance in an alternating-gradient magnetic transport system. The radial quadrupole electric eld forces on the charged particles in the Paul Trap are analogous to the radial forces on the charged particles in the quadrupole magnetic transport system. The amplitude of oscillating voltage applied to the cylindrical electrodes in PTSX is equivalent to the quadrupole magnetic eld gradient in accelerators. The temporal periodicity in PTSX corresponds to the spatial periodicity in magnetic transport system. This thesismore » focuses on investigations of envelope instabilities and collective mode excitations, properties of high-intensity beams with significant space-charge effects, random noise-induced beam degradation and a laser-induced-fluorescence diagnostic. To better understand the nonlinear dynamics of the charged particle beams, it is critical to understand the collective processes of the charged particles. Charged particle beams support a variety of collective modes, among which the quadrupole mode and the dipole mode are of the greatest interest. We used quadrupole and dipole perturbations to excite the quadrupole and dipole mode respectively and study the effects of those collective modes on the charge bunch. The experimental and particle-in-cell (PIC) simulation results both show that when the frequency and the spatial structure of the external perturbation are matched with the corresponding collective mode, that mode will be excited to a large amplitude and resonates strongly with the external perturbation, usually causing expansion of the charge bunch and loss of particles. Machine imperfections are inevitable for accelerator systems, and we use random noise to simulate the effects of machine imperfection on the charged particle beams. The random noise can be Fourier decomposed into various frequency components and experimental results show that when the random noise has a large frequency component that matches a certain collective mode, the mode will also be excited and cause heating of the charge bunch. It is also noted that by rearranging the order of the random noise, the adverse effects of the random noise may be eliminated. As a non-destructive diagnostic method, a laser-induced- fluorescence (LIF) diagnostic is developed to study the transverse dynamics of the charged particle beams. The accompanying barium ion source and dye laser system are developed and tested.« less

  14. Nanoscale biomimetics studies of Salvinia molesta for micropattern fabrication.

    PubMed

    Hunt, James; Bhushan, Bharat

    2011-11-01

    The emerging field of biomimetics allows one to take inspiration from nature and mimic it in order to create various products, devices and structures. There are a large number of objects, including bacteria, plants, land and aquatic animals and seashells, with properties of commercial interest. The subject of interest for this research is the water fern Salvinia molesta because of its ability to trap air. Air-retaining surfaces are of technological interest due to their ability to reduce drag when used for fluid transport, ship coatings and other submersible industrial products in which drag is a concern. The purpose of this research is to mimic the air trapping ability of S. molesta in order to prove that a structure can be created in the lab that can mimic the behavior of the fern as well as demonstrate microfabrication techniques that can be utilized in industry to produce such materials. In this work, a novel methodology for the fabrication of microstructures that mimic the water-pinning and air-trapping ability of S. molesta is introduced. Water contact angle, water roll angle and adhesive force of the new microstructure and water fern are investigated. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Experimental apparatus for overlapping a ground-state cooled ion with ultracold atoms

    NASA Astrophysics Data System (ADS)

    Meir, Ziv; Sikorsky, Tomas; Ben-shlomi, Ruti; Akerman, Nitzan; Pinkas, Meirav; Dallal, Yehonatan; Ozeri, Roee

    2018-03-01

    Experimental realizations of charged ions and neutral atoms in overlapping traps are gaining increasing interest due to their wide research application ranging from chemistry at the quantum level to quantum simulations of solid state systems. In this paper, we describe our experimental system in which we overlap a single ground-state cooled ion trapped in a linear Paul trap with a cloud of ultracold atoms such that both constituents are in the ?K regime. Excess micromotion (EMM) currently limits atom-ion interaction energy to the mK energy scale and above. We demonstrate spectroscopy methods and compensation techniques which characterize and reduce the ion's parasitic EMM energy to the ?K regime even for ion crystals of several ions. We further give a substantial review on the non-equilibrium dynamics which governs atom-ion systems. The non-equilibrium dynamics is manifested by a power law distribution of the ion's energy. We also give an overview on the coherent and non-coherent thermometry tools which can be used to characterize the ion's energy distribution after single to many atom-ion collisions.

  16. Bacterial Trapping in Porous Media Flows

    NASA Astrophysics Data System (ADS)

    Dehkharghani, Amin; Waisbord, Nicolas; Dunkel, Jörn; Guasto, Jeffrey

    2016-11-01

    Swimming bacteria inhabit heterogeneous, microstructured environments that are often characterized by complex, ambient flows. Understanding the physical mechanisms underlying cell transport in these systems is key to controlling important processes such as bioremediation in porous soils and infections in human tissues. We study the transport of swimming bacteria (Bacillus subtilis) in quasi-two-dimensional porous microfluidic channels with a range of periodic microstructures and flow strengths. Measured cell trajectories and the local cell number density reveal the formation of filamentous cell concentration patterns within the porous structures. The local cell densification is maximized at shear rates in the range 1-10 s-1, but widely varies with pore geometry and flow topology. Experimental observations are complemented by Langevin simulations to demonstrate that the filamentous patterns result from a coupling of bacterial motility to the complex flow fields via Jeffery orbits, which effectively 'trap' the bacteria on streamlines. The resulting microscopic heterogeneity observed here suppresses bacterial transport and likely has implications for both mixing and cell nutrient uptake in porous media flows. NSF CBET-1511340.

  17. Adjustable Spin-Spin Interaction with 171Yb+ ions and Addressing of a Quantum Byte

    NASA Astrophysics Data System (ADS)

    Wunderlich, Christof

    2015-05-01

    Trapped atomic ions are a well-advanced physical system for investigating fundamental questions of quantum physics and for quantum information science and its applications. When contemplating the scalability of trapped ions for quantum information science one notes that the use of laser light for coherent operations gives rise to technical and also physical issues that can be remedied by replacing laser light by microwave (MW) and radio-frequency (RF) radiation employing suitably modified ion traps. Magnetic gradient induced coupling (MAGIC) makes it possible to coherently manipulate trapped ions using exclusively MW and RF radiation. After introducing the general concept of MAGIC, I shall report on recent experimental progress using 171Yb+ ions, confined in a suitable Paul trap, as effective spin-1/2 systems interacting via MAGIC. Entangling gates between non-neighbouring ions will be presented. The spin-spin coupling strength is variable and can be adjusted by variation of the secular trap frequency. In general, executing a quantum gate with a single qubit, or a subset of qubits, affects the quantum states of all other qubits. This reduced fidelity of the whole quantum register may preclude scalability. We demonstrate addressing of individual qubits within a quantum byte (eight qubits interacting via MAGIC) using MW radiation and measure the error induced in all non-addressed qubits (cross-talk) associated with the application of single-qubit gates. The measured cross-talk is on the order 10-5 and therefore below the threshold commonly agreed sufficient to efficiently realize fault-tolerant quantum computing. Furthermore, experimental results on continuous and pulsed dynamical decoupling (DD) for protecting quantum memories and quantum gates against decoherence will be briefly discussed. Finally, I report on using continuous DD to realize a broadband ultrasensitive single-atom magnetometer.

  18. Studies of emittance growth and halo particle production in intense charged particle beams using the Paul Trap Simulator Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gilson, Erik P.; Davidson, Ronald C.; Dorf, Mikhail

    2010-05-15

    The Paul Trap Simulator Experiment (PTSX) is a compact laboratory experiment that places the physicist in the frame-of-reference of a long, charged-particle bunch coasting through a kilometers-long magnetic alternating-gradient (AG) transport system. The transverse dynamics of particles in both systems are described by the same set of equations, including nonlinear space-charge effects. The time-dependent voltages applied to the PTSX quadrupole electrodes in the laboratory frame are equivalent to the spatially periodic magnetic fields applied in the AG system. The transverse emittance of the charge bunch, which is a measure of the area in the transverse phase space that the beammore » distribution occupies, is an important metric of beam quality. Maintaining low emittance is an important goal when defining AG system tolerances and when designing AG systems to perform beam manipulations such as transverse beam compression. Results are reviewed from experiments in which white noise and colored noise of various amplitudes and durations have been applied to the PTSX electrodes. This noise is observed to drive continuous emittance growth and increase in root-mean-square beam radius over hundreds of lattice periods. Additional results are reviewed from experiments that determine the conditions necessary to adiabatically reduce the charge bunch's transverse size and simultaneously maintain high beam quality. During adiabatic transitions, there is no change in the transverse emittance. The transverse compression can be achieved either by a gradual change in the PTSX voltage waveform amplitude or frequency. Results are presented from experiments in which low emittance is achieved by using focusing-off-defocusing-off waveforms.« less

  19. Precision Test of the Isobaric Multiplet Mass Equation in the A = 32, T = 2 Quintet

    NASA Astrophysics Data System (ADS)

    Ferrer, R.; Kwiatkowski, A. A.; Bollen, G.; Campbell, C. M.; Folden, C. M., III; Lincoln, D.; Morrissey, D. J.; Pang, G. K.; Prinke, A.; Savory, J.; Schwarz, S.

    2008-10-01

    Masses of the radionuclides ^32,33Si and ^34P and of the stable nuclide ^32S have been measured with the Low Energy Beam and Ion Trap (LEBIT) Penning trap mass spectrometer. Relative mass uncertainties of 3 x 10-8 and better have been achieved. The measured mass value of ^32Si differs from the literature value [1,2] by four standard deviations. The precise mass determination of ^32Si and ^32S have been employed to test the isobaric multiplet mass equation for the A = 32, T= 2 isospin quintet. The experimental results indicate a significant deviation from the quadratic form. This work has been supported by Michigan State University, the NSF under contract number PHY- 0606007, and the DOE under the contract DE-FG02-00ER41144. References: 1. G. Audi, A.H. Wapstra, and C. Thibault, Nucl. Phys. A729 (2003) 337 2. A. Paul, S. R"ottger, A. Zimbal, and U. Keyser, Hyperfine Interact. 132 (2001) 189

  20. Observation of a Discrete Time Crystal

    NASA Astrophysics Data System (ADS)

    Kyprianidis, A.; Zhang, J.; Hess, P.; Becker, P.; Lee, A.; Smith, J.; Pagano, G.; Potter, A.; Vishwanath, A.; Potirniche, I.-D.; Yao, N.; Monroe, C.

    2017-04-01

    Spontaneous symmetry breaking is a key concept in the understanding of many physical phenomena, such as the formation of spatial crystals and the phase transition from paramagnetism to magnetic order. While the breaking of time translation symmetry is forbidden in equilibrium systems, it is possible for non-equilibrium Floquet driven systems to break a discrete time translation symmetry, and we present clear signatures of the formation of such a discrete time crystal. We apply a time periodic Hamiltonian to a chain of interacting spins under many-body localization conditions and observe the system's sub-harmonic response at twice that period. This spontaneous doubling of the periodicity is robust to external perturbations. We represent the spins with a linear chain of trapped 171Yb+ ions in an rf Paul trap, generate spin-spin interactions through spin-dependent optical dipole forces, and measure each spin using state-dependent fluorescence. This work is supported by the ARO Atomic Physics Program, the AFOSR MURI on Quantum Measurement and Verification, and the NSF Physics Frontier Center at JQI.

  1. Relevance of GaAs(001) surface electronic structure for high frequency dispersion on n-type accumulation capacitance

    NASA Astrophysics Data System (ADS)

    Pi, T. W.; Chen, W. S.; Lin, Y. H.; Cheng, Y. T.; Wei, G. J.; Lin, K. Y.; Cheng, C.-P.; Kwo, J.; Hong, M.

    2017-01-01

    This study investigates the origin of long-puzzled high frequency dispersion on the accumulation region of capacitance-voltage characteristics in an n-type GaAs-based metal-oxide-semiconductor. Probed adatoms with a high Pauling electronegativity, Ag and Au, unexpectedly donate charge to the contacted As/Ga atoms of as-grown α2 GaAs(001)-2 × 4 surfaces. The GaAs surface atoms behave as charge acceptors, and if not properly passivated, they would trap those electrons accumulated at the oxide and semiconductor interface under a positive bias. The exemplified core-level spectra of the Al2O3/n-GaAs(001)-2 × 4 and the Al2O3/n-GaAs(001)-4 × 6 interfaces exhibit remnant of pristine surface As emission, thereby causing high frequency dispersion in the accumulation region. For the p-type GaAs, electrons under a negatively biased condition are expelled from the interface, thereby avoiding becoming trapped.

  2. Control of the kerf size and microstructure in Inconel 738 superalloy by femtosecond laser beam cutting

    NASA Astrophysics Data System (ADS)

    Wei, J.; Ye, Y.; Sun, Z.; Liu, L.; Zou, G.

    2016-05-01

    Femtosecond laser beam cutting is becoming widely used to meet demands for increasing accuracy in micro-machining. In this paper, the effects of processing parameters in femtosecond laser beam cutting on the kerf size and microstructure in Inconel 738 have been investigated. The defocus, pulse width and scanning speed were selected to study the controllability of the cutting process. Adjusting and matching the processing parameters was a basic enhancement method to acquire well defined kerf size and the high-quality ablation of microstructures, which has contributed to the intensity clamping effect. The morphology and chemical compositions of these microstructures on the cut surface have been characterized by a scanning electron microscopy equipped with an energy dispersive X-ray spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Additionally, the material removal mechanism and oxidation mechanism on the Inconel 738 cut surface have also been discussed on the basis of the femtosecond laser induced normal vaporization or phase explosion, and trapping effect of the dangling bonds.

  3. Athermal fading of luminescence in Al2 O3 ceramic substrates

    NASA Astrophysics Data System (ADS)

    Terry, Ian; Kouroukla, Eftychia; Bailiff, Ian K.

    2015-03-01

    Retrospective dosimetry aims to reconstruct ionising radiation dose to populations following a radiological incident using materials not designed for that purpose. Sintered alumina ceramic can function as a dosimeter with its luminescence properties and related trapped charge storage mechanism. Its widespread use as a substrate in surface mount devices and incorporation in devices such as mobile phones make it a ubiquitous potential dosimeter. We investigated the optically (OSL) and thermally (TL) stimulated luminescence properties of sintered alumina substrates. In contrast to their single crystal analogue developed for personal dosimetry, Al2O3:C, the substrates exhibit a significant loss of trapped charge (fading) within hours following irradiation at RT that seriously limits their utility for dosimetry over an extended timescale. The fading rates of OSL and TL signals of 0402 resistors were analysed under various storage conditions (time and temperature), complemented by a study of their microstructure. The results support a model of athermal loss of trapped charge due to electron tunnelling from trapping states; this contrasting behaviour is attributed to a physical modification of the trap environment arising from the manufacturing process.

  4. Cooling and heating of the quantum motion of trapped cadmium(+) ions

    NASA Astrophysics Data System (ADS)

    Deslauriers, Louis

    The quest for a quantum system best satisfying the stringent requirements of a quantum information processor has made tremendous progress in many fields of physics. In the last decade, trapped ions have been established as one of the most promising architectures to accomplish the task. Internal states of an ion which can have extremely long coherence time can be used to store a quantum bit, and therefore allow many gate operations before the coherence is lost. Entanglement between multiple ions can be established via Coulomb interactions mediated by appropriate laser fields. Entangling schemes usually require the ions to be initialized to near their motional ground state. The interaction of fluctuating electric fields with the motional state of the ion leads to heating and thus to decoherence for entanglement generation limiting the fidelity of quantum logic gates. Effective ground state cooling of trapped ion motion and suppression of motional heating are thus crucial to many applications of trapped ions in quantum information science. In this thesis, I describe the implementation and study of several components of a Cadmium-ion-based quantum information processor, with special emphasis on the control and decoherence of trapped ion motion. I first discuss the building and design of various ion traps that were used in this work. I also report on the use of ultrafast laser pulses to photoionize and load cadmium ions in a variety of rf Paul trap geometries. A detailed analysis of the photoionization scheme is presented, along with its dependence on controlled experimental parameters. I then describe the implementation of Raman sideband cooling on a single trapped 111Cd+ ion to the ground state of motion, where a ground state population of 97% was achieved. The efficacy of this cooling technique is discussed with respect to different initial motional state distributions and its sensitivity to the presence of motional heating. I also present an experiment where the motion of a single trapped 112Cd+ ion is sympathetically cooled by directly Doppler cooling a 114Cd+ ion in the same trap. The implications of this result are relevant to the scaling of a trapped ion quantum computer, where the unwanted motion of an ion crystal can be quenched while not affecting the internal states of the qubit ions. (Abstract shortened by UMI.)

  5. Free Volume Structure of Acrylic-Type Dental Nanocomposites Tested with Annihilating Positrons.

    PubMed

    Shpotyuk, Olha; Ingram, Adam; Shpotyuk, Oleh

    2016-12-01

    Positron annihilation spectroscopy in lifetime measuring mode exploring conventional fast-fast coincidence ORTEC system is employed to characterize free volume structure of commercially available acrylic-type dental restorative composite Charisma® (Heraeus Kulzer GmbH, Germany). The measured lifetime spectra for uncured and light-cured composites are reconstructed from unconstrained x3-term fitting and semi-empirical model exploring x3-x2-coupling decomposition algorithm. The governing channel of positron annihilation in the composites studied is ascribed to mixed positron-Ps trapping, where Ps decaying in the third component is caused entirely by input from free-volume holes in polymer matrix, while the second component is defined by free positron trapping in interfacial free-volume holes between filler nanoparticles and surrounded polymer matrix. Microstructure scenario of the photopolymerization shrinkage includes cross-linking of structural chains in polymer matrix followed by conversion of bound positron-electron (positronium) traps in positron-trapping interfacial free-volume voids in a vicinity of agglomerated filler nanoparticles.

  6. A Single-Ion Reservoir as a High-Sensitive Sensor of Electric Signals.

    PubMed

    Domínguez, Francisco; Arrazola, Iñigo; Doménech, Jaime; Pedernales, Julen S; Lamata, Lucas; Solano, Enrique; Rodríguez, Daniel

    2017-08-21

    A single-ion reservoir has been tested, and characterized in order to be used as a highly sensitive optical detector of electric signals arriving at the trapping electrodes. Our system consists of a single laser-cooled 40 Ca + ion stored in a Paul trap with rotational symmetry. The performance is observed through the axial motion of the ion, which is equivalent to an underdamped and forced oscillator. Thus, the results can be projected also to Penning traps. We have found that, for an ion oscillator temperature T axial  ≲ 10 mK in the forced-frequency range ω z  = 2π × (80,200 kHz), the reservoir is sensitive to a time-varying electric field equivalent to an electric force of 5.3(2) neV/μm, for a measured quality factor Q = 3875(45), and a decay time constant γ z  = 88(2) s -1 . This method can be applied to measure optically the strength of an oscillating field or induced (driven) charge in this frequency range within times of tens of milliseconds. Furthermore the ion reservoir has been proven to be sensitive to electrostatic forces by measuring the ion displacement. Since the heating rate is below 0.3 μeV/s, this reservoir might be used as optical detector for any ion or bunch of charged particles stored in an adjacent trap.

  7. Quantum simulations of the Ising model with trapped ions: Devil's staircase and arbitrary lattice proposal

    NASA Astrophysics Data System (ADS)

    Korenblit, Simcha

    A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long-range effective spin-spin interactions and allow the simulation of spin Hamiltonians that possess nontrivial phases and dynamics. We trap linear chains of 171Yb+ ions in a Paul trap, and constrain the occupation of energy levels to the ground hyperne clock-states, creating a qubit or pseudo-spin 1/2 system. We proceed to implement spin-spin couplings between two ions using the far detuned Molmer-Sorenson scheme and perform adiabatic quantum simulations of Ising Hamiltonians with long-range couplings. We then demonstrate our ability to control the sign and relative strength of the interaction between three ions. Using this control, we simulate a frustrated triangular lattice, and for the first time establish an experimental connection between frustration and quantum entanglement. We then scale up our simulation to show phase transitions from paramagnetism to ferromagnetism for nine ions, and to anti-ferromagnetism for sixteen ions. The experimental work culminates with our most complicated Hamiltonian---a long range anti-ferromagnetic Ising interaction between 10 ions with a biasing axial field. Theoretical work presented in this thesis shows how the approach to quantum simulation utilized in this thesis can be further extended and improved. It is shown how appropriate design of laser fields can provide for arbitrary multidimensional spin-spin interaction graphs even for the case of a linear spatial array of ions. This scheme uses currently existing trap technology and is scalable to levels where classical methods of simulation are intractable.

  8. Tunable Microfluidic Devices for Hydrodynamic Fractionation of Cells and Beads: A Review

    PubMed Central

    Alvankarian, Jafar; Majlis, Burhanuddin Yeop

    2015-01-01

    The adjustable microfluidic devices that have been developed for hydrodynamic-based fractionation of beads and cells are important for fast performance tunability through interaction of mechanical properties of particles in fluid flow and mechanically flexible microstructures. In this review, the research works reported on fabrication and testing of the tunable elastomeric microfluidic devices for applications such as separation, filtration, isolation, and trapping of single or bulk of microbeads or cells are discussed. Such microfluidic systems for rapid performance alteration are classified in two groups of bulk deformation of microdevices using external mechanical forces, and local deformation of microstructures using flexible membrane by pneumatic pressure. The main advantage of membrane-based tunable systems has been addressed to be the high capability of integration with other microdevice components. The stretchable devices based on bulk deformation of microstructures have in common advantage of simplicity in design and fabrication process. PMID:26610519

  9. Understanding the Interaction between a Steel Microstructure and Hydrogen

    PubMed Central

    Depover, Tom; Laureys, Aurélie; Wallaert, Elien

    2018-01-01

    The present work provides an overview of the work on the interaction between hydrogen (H) and the steel’s microstructure. Different techniques are used to evaluate the H-induced damage phenomena. The impact of H charging on multiphase high-strength steels, i.e., high-strength low-alloy (HSLA), transformation-induced plasticity (TRIP) and dual phase (DP) is first studied. The highest hydrogen embrittlement resistance is obtained for HSLA steel due to the presence of Ti- and Nb-based precipitates. Generic Fe-C lab-cast alloys consisting of a single phase, i.e., ferrite, bainite, pearlite or martensite, and with carbon contents of approximately 0, 0.2 and 0.4 wt %, are further considered to simplify the microstructure. Finally, the addition of carbides is investigated in lab-cast Fe-C-X alloys by adding a ternary carbide forming element to the Fe-C alloys. To understand the H/material interaction, a comparison of the available H trapping sites, the H pick-up level and the H diffusivity with the H-induced mechanical degradation or H-induced cracking is correlated with a thorough microstructural analysis. PMID:29710803

  10. Magnetophoretic manipulation in microsystem using carbonyl iron-polydimethylsiloxane microstructures

    PubMed Central

    Faivre, Magalie; Gelszinnis, Renaud; Degouttes, Jérôme; Terrier, Nicolas; Rivière, Charlotte; Ferrigno, Rosaria; Deman, Anne-Laure

    2014-01-01

    This paper reports the use of a recent composite material, noted hereafter i-PDMS, made of carbonyl iron microparticles mixed in a PolyDiMethylSiloxane (PDMS) matrix, for magnetophoretic functions such as capture and separation of magnetic species. We demonstrated that this composite which combine the advantages of both components, can locally generate high gradients of magnetic field when placed between two permanent magnets. After evaluating the magnetic susceptibility of the material as a function of the doping ratio, we investigated the molding resolution offered by i-PDMS to obtain microstructures of various sizes and shapes. Then, we implemented 500 μm i-PDMS microstructures in a microfluidic channel and studied the influence of flow rate on the deviation and trapping of superparamagnetic beads flowing at the neighborhood of the composite material. We characterized the attraction of the magnetic composite by measuring the distance from the i-PDMS microstructure, at which the beads are either deviated or captured. Finally, we demonstrated the interest of i-PDMS to perform magnetophoretic functions in microsystems for biological applications by performing capture of magnetically labeled cells. PMID:25332740

  11. High accuracy indirect optical manipulation of live cells with functionalized microtools

    NASA Astrophysics Data System (ADS)

    Vizsnyiczai, Gaszton; Aekbote, Badri L.; Buzás, András.; Grexa, István.; Ormos, Pál.; Kelemen, Lóránd

    2016-09-01

    Optical micro manipulation of live cells has been extensively used to study a wide range of cellular phenomena with relevance in basic research or in diagnostics. The approaches span from manipulation of many cells for high throughput measurement or sorting, to more elaborated studies of intracellular events on trapped single cells when coupled with modern imaging techniques. In case of direct cell trapping the damaging effects of light-cell interaction must be minimized, for instance with the choice of proper laser wavelength. Microbeads have already been used for trapping cells indirectly thereby reducing the irradiation damage and increasing trapping efficiency with their high refractive index contrast. We show here that such intermediate objects can be tailor-made for indirect cell trapping to further increase cell-to-focal spot distance while maintaining their free and fast maneuverability. Carefully designed structures were produced with two-photon polymerization with shapes optimized for effective manipulation and cell attachment. Functionalization of the microstructures is also presented that enables cell attachment to them within a few seconds with strength much higher that the optical forces. Fast cell actuation in 6 degrees of freedom is demonstrated with the outlook to possible applications in cell imaging.

  12. Uv Spectroscopy on Gas Phase Cu(I)-BIPYRIDYL Complexes

    NASA Astrophysics Data System (ADS)

    Xu, Shuang; Christopher, Casey; Weber, J. Mathias

    2015-06-01

    Transition metal complexes with bipyridine ligands are of great interest in metal-organic chemistry, since they are prototypes for many applications in photochemistry and homogeneous catalysis. Under-coordinated bipyridyl complexes are elusive species in the condensed phase, and the ligand-induced changes in electronic structure are of fundamental interest. We present UV photodissociation spectra of mass-selected monocationic copper(I)-bipyridyl complexes [bpy-Cu-L]+ with different ligands (L = H2O, D2, N2, MeOH, Cl). Complexes were prepared via electrospray ionization of copper/bipyridine solutions followed by accumulation and buffer gas cooling in a cryogenic Paul trap. In addition, we show spectra of similar species based on copper oxide, [bpy-CuO-L]+.

  13. Analysis of continuously rotating quadrupole focusing channels using generalized Courant-Snyder theory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, Moses; Qin, Hong; Gilson, Erik

    2013-01-01

    By extending the recently developed generalized Courant-Snyder theory for coupled transverse beam dynamics, we have constructed the Gaussian beam distribution and its projections with arbitrary mode emittance ratios. The new formulation has been applied to a continuously-rotating quadrupole focusing channel because the basic properties of this channel are known theoretically and could also be investigated experimentally in a compact setup such as the linear Paul trap configuration. The new formulation retains a remarkably similar mathematical structure to the original Courant-Snyder theory, and thus provides a powerful theoretical tool to investigate coupled transverse beam dynamics in general and more complex linearmore » focusing channels.« less

  14. Analysis of continuously rotating quadrupole focusing channels using generalized Courant-Snyder theory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, Moses; Qin, Hong; Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026

    2013-08-15

    By extending the recently developed generalized Courant-Snyder theory for coupled transverse beam dynamics, we have constructed the Gaussian beam distribution and its projections with arbitrary mode emittance ratios. The new formulation has been applied to a continuously rotating quadrupole focusing channel because the basic properties of this channel are known theoretically and could also be investigated experimentally in a compact setup such as the linear Paul trap configuration. The new formulation retains a remarkably similar mathematical structure to the original Courant-Snyder theory, and thus, provides a powerful theoretical tool to investigate coupled transverse beam dynamics in general and more complexmore » linear focusing channels.« less

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koepke, Mark

    Collaborative research between WVU and PPPL was carried out at WVU for the purpose of incorporating the sophisticated diagnostic technique known as laser-induced fluorescence (LIF) in the Paul-Trap Simulation Experiment (PTSX) at PPPL. WVU assembled a LIF system at WVU, transported it to PPPL, helped make LIF experiments on the PTSX device, participated in PTSX science, and trained PPPL staff in LIF techniques. In summary, WVU refurbished a non-operational LIF system being loaned from University of Maryland to PPPL and, by doing so, provided PPPL with additional diagnostic capability for its PTSX device and other General Plasma Science experiments. WVUmore » students, staff, and faculty will visit PPPL to collaborate on PTSX experiments in the future.« less

  16. In Situ formation of microstructures near live cells using spatially structured near-infrared laser microbeam

    NASA Astrophysics Data System (ADS)

    Ingle, Ninad; Gu, Ling; Mohanty, Samarendra K.

    2011-03-01

    Here, we report in situ formation of microstructures from the regular constituents of culture media near live cells using spatially-structured near infrared (NIR) laser beam. Irradiation with the continuous wave (cw) NIR laser microbeam for few seconds onto the regular cell culture media containing fetal bovine serum resulted in accumulation of dense material inside the media as evidenced by phase contrast microscopy. The time to form the phase dense material was found to depend on the laser beam power. Switching off the laser beam led to diffusion of phase dark material. However, the proteins could be stitched together by use of carbon nanoparticles and continuous wave (cw) Ti: Sapphire laser beam. Further, by use of spatially-structured beam profiles different structures near live cells could be formed. The microfabricated structure could be held by the Gravito-optical trap and repositioned by movement of the sample stage. Orientation of these microstructures was achieved by rotating the elliptical laser beam profile. Thus, multiple microstructures were formed and organized near live cells. This method would enable study of response of cells/axons to the immediate physical hindrance provided by such structure formation and also eliminate the biocompatibility requirement posed on artificial microstructure materials.

  17. Field-Induced Disorder and Carrier Localization in Molecular Organic Transistors

    NASA Astrophysics Data System (ADS)

    Ando, M.; Minakata, T.; Duffy, C.; Sirringhaus, H.

    2009-06-01

    We propose a "field-induced polymorphous disorder" model to explain bias-stress instability in molecular organic thin-film transistors, based on the experimental results showing the strong correlation between the micro-structural change in semiconductor layer composed of penrtacene molecules and the threshold voltage (Vth) shift due to electron trapping in a reversible manner under the successive bias-stress, thermal annealing, and light irradiation.

  18. Validation of a freshwater Otolith microstructure pattern for Nisqually Chinook Salmon (Oncorhynchus tshawytscha)

    USGS Publications Warehouse

    Lind-Null, Angie; Larsen, Kim

    2011-01-01

    The Nisqually Fall Chinook salmon (Oncorhynchus tshawytscha) population is one of 27 stocks in the Puget Sound (Washington) evolutionarily significant unit listed as threatened under the federal Endangered Species Act (ESA). Extensive restoration of the Nisqually River delta ecosystem has taken place to assist in recovery of the stock since estuary habitat is a critical transition zone for juvenile fall Chinook salmon. A pre-restoration baseline that includes the characterization of life history strategies, estuary residence times, growth rates and habitat use is needed to evaluate the potential response of hatchery and natural origin Chinook salmon to restoration efforts and to determine restoration success. Otolith microstructure analysis was selected as a tool to examine Chinook salmon life history, growth and residence in the Nisqually River estuary. The purpose of the current study is to incorporate microstructural analysis from the otoliths of juvenile Nisqually Chinook salmon collected at the downstream migrant trap within true freshwater (FW) habitat of the Nisqually River. The results from this analysis confirmed the previously documented Nisqually-specific FW microstructure pattern and revealed a Nisqually-specific microstructure pattern early in development (“developmental pattern”). No inter-annual variation in the microstructure pattern was visually observed when compared to samples from previous years. Furthermore, the Nisqually-specific “developmental pattern” and the FW microstructure pattern used in combination during analysis will allow us to recognize and separate with further confidence future unmarked Chinook salmon otolith collections into Nisqually-origin (natural or unmarked hatchery) and non-Nisqually origin categories. Freshwater mean increment width, growth rate and residence time were also calculated.

  19. Microfluidic devices with permeable polymer barriers for capture and transport of biomolecules and cells.

    PubMed

    Lee, Ho Suk; Chu, Wai Keung; Zhang, Kun; Huang, Xiaohua

    2013-09-07

    We report a method for fabricating permeable polymer microstructure barriers in polydimethylsiloxane (PDMS) microfluidic devices and the use of the devices to capture and transport DNA and cells. The polymer microstructure in a desired location in a fluidic channel is formed in situ by the polymerization of acrylamide and polyethylene diacrylate cross-linker (PEG-DA) monomer in a solution which is trapped in the location using a pair of PDMS valves. The porous polymer microstructure provides a mechanical barrier to convective fluid flow in the channel or between two microfluidic chambers while it still conducts ions or small charged species under an electric field, allowing for the rapid capture and transport of biomolecules and cells by electrophoresis. We have demonstrated the application of the devices for the rapid capture and efficient release of bacteriophage λ genomic DNA, solution exchange and for the transport and capture of HeLa cells. Our devices will enable the multi-step processing of biomolecules and cells or individual cells within a single microfluidic chamber.

  20. Efficient and robust photo-ionization loading of beryllium ions

    NASA Astrophysics Data System (ADS)

    Wolf, Sebastian; Studer, Dominik; Wendt, Klaus; Schmidt-Kaler, Ferdinand

    2018-02-01

    We demonstrate the efficient generation of Be^+ ions with a 60 ns and 150 nJ laser pulse near 235 nm for two-step photo-ionization, proven by subsequent counting of the number of ions loaded into a linear Paul trap. The bandwidth and power of the laser pulse are chosen in such a way that a first, resonant step fully saturates the entire velocity distribution of beryllium atoms effusing from a thermal oven. The second excitation step is driven by the same light field causing efficient non-resonant ionization. Our ion-loading scheme has a similar efficiency as compared to former pathways using two-photon continuous wave laser excitation, but with an order of magnitude lower than average UV light power.

  1. Gas atomized precursor alloy powder for oxide dispersion strengthened ferritic stainless steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rieken, Joel

    Gas atomization reaction synthesis (GARS) was employed as a simplified method for producing precursor powders for oxide dispersion strengthened (ODS) ferritic stainless steels (e.g., Fe-Cr-Y-(Ti,Hf)-O), departing from the conventional mechanical alloying (MA) process. During GARS processing a reactive atomization gas (i.e., Ar-O 2) was used to oxidize the powder surfaces during primary break-up and rapid solidification of the molten alloy. This resulted in envelopment of the powders by an ultra-thin (t < 150 nm) metastable Cr-enriched oxide layer that was used as a vehicle for solid-state transport of O into the consolidated microstructure. In an attempt to better understand themore » kinetics of this GARS reaction, theoretical cooling curves for the atomized droplets were calculated and used to establish an oxidation model for this process. Subsequent elevated temperature heat treatments, which were derived from Rhines pack measurements using an internal oxidation model, were used to promote thermodynamically driven O exchange reactions between trapped films of the initial Cr-enriched surface oxide and internal Y-enriched intermetallic precipitates. This novel microstructural evolution process resulted in the successful formation of nano-metric Y-enriched dispersoids, as confirmed using high energy X-ray diffraction and transmission electron microscopy (TEM), equivalent to conventional ODS alloys from MA powders. The thermal stability of these Y-enriched dispersoids was evaluated using high temperature (1200°C) annealing treatments ranging from 2.5 to 1,000 hrs of exposure. In a further departure from current ODS practice, replacing Ti with additions of Hf appeared to improve the Y-enriched dispersoid thermal stability by means of crystal structure modification. Additionally, the spatial distribution of the dispersoids was found to depend strongly on the original rapidly solidified microstructure. To exploit this, ODS microstructures were engineered from different powder particle size ranges, illustrating microstructural control as a function of particle solidification rate. The consolidation of ultra-fine powders (dia. ≤ 5μm) resulted in a significant reduction in dispersoid size and spacing, consistent with initial scanning electron microscopy studies on as-atomized cross-sectioned particles that suggested that these powders solidified above the threshold velocity to effectively solute trap Y within the α-(Fe,Cr) matrix. Interestingly, when the solidification velocity as a function of particle size was extracted from the aforementioned theoretical particle cooling curves, it could be offered as supporting evidence for these microstructure observations. Thermal-mechanical treatments also were used to create and evaluate the stability of a dislocation substructure within these alloys, using microhardness and TEM analysis of the alloy sub-grain and grain structure. Moreover, elevated temperature tensile tests up to 800°C were used to assess the initial mechanical strength of the ODS microstructure.« less

  2. Paul Fleming | NREL

    Science.gov Websites

    Paul Fleming Photo of Paul Fleming Paul Fleming Researcher IV-Control Engineering Paul.Fleming analysis of control systems for wind energy. Paul co-designed the control system used for field testing of advanced control systems on the CARTs, located at the NWTC. Since joining NREL, he has researched topics

  3. Paul Veers | NREL

    Science.gov Websites

    Veers Photo of Paul Veers Paul Veers Group Research Manager III-Mechanical Engineering Paul.Veers @nrel.gov | 303-384-7197 Paul Veers is the Chief Engineer at the NWTC and represents NREL on DOE's Staff at Sandia National Laboratories. Paul has authored over 70 articles, papers, book chapters, and

  4. Paul Denholm | NREL

    Science.gov Websites

    Denholm Photo of Paul Denholm Paul Denholm Principal Energy Analyst Paul.Denholm@nrel.gov | 303-384 -7488 Paul Denholm is a member of the Grid Systems Analysis Group in the Strategic Energy Analysis Center. Paul is a leading researcher in grid applications for energy storage and solar energy. He

  5. Positron annihilation lifetime study of oxide dispersion strengthened steels

    NASA Astrophysics Data System (ADS)

    Krsjak, V.; Szaraz, Z.; Hähner, P.

    2012-09-01

    A comparative positron annihilation lifetime study has been performed on various commercial ferritic and ferritic/martensitic oxide dispersion strengthened (ODS) steels. Both as-extruded and recrystallized materials were investigated. In the materials with recrystallized coarse-grained microstructures, only the positron trapping at small vacancy clusters and yttria nanofeatures was observed. Materials which had not undergone recrystallization treatment clearly showed additional positron trapping which is associated with dislocations. Dislocation densities were calculated from a two-component decomposition of the positron lifetime spectra by assuming the first component to be a superposition of the bulk controlled annihilation rate and the dislocation controlled trapping rate. The second component (which translates into lifetimes of 240-260 ps) was found to be well separated in all those ODS materials. This paper presents the potentialities and limitations of the positron annihilation lifetime spectroscopy, and discusses the results of the experimental determination of the defect concentrations and sensitivity of this technique to the material degradation due to thermally induced precipitation of chromium-rich α' phases.

  6. Differentiation of the Stereochemistry and Anomeric Configuration for 1-3 Linked Disaccharides Via Tandem Mass Spectrometry and 18O-labeling

    NASA Astrophysics Data System (ADS)

    Konda, Chiharu; Bendiak, Brad; Xia, Yu

    2012-02-01

    Collision-induced dissociation (CID) of deprotonated hexose-containing disaccharides ( m/z 341) with 1-2, 1-4, and 1-6 linkages yields product ions at m/z 221, which have been identified as glycosyl-glycolaldehyde anions. From disaccharides with these linkages, CID of m/z 221 ions produces distinct fragmentation patterns that enable the stereochemistries and anomeric configurations of the non-reducing sugar units to be determined. However, only trace quantities of m/z 221 ions can be generated for 1-3 linkages in Paul or linear ion traps, preventing further CID analysis. Here we demonstrate that high intensities of m/z 221 ions can be built up in the linear ion trap (Q3) from beam-type CID of a series of 1-3 linked disaccharides conducted on a triple quadrupole/linear ion trap mass spectrometer. 18O-labeling at the carbonyl position of the reducing sugar allowed mass-discrimination of the "sidedness" of dissociation events to either side of the glycosidic linkage. Under relatively low energy beam-type CID and ion trap CID, an m/z 223 product ion containing 18O predominated. It was a structural isomer that fragmented quite differently than the glycosyl-glycolaldehydes and did not provide structural information about the non-reducing sugar. Under higher collision energy beam-type CID conditions, the formation of m/z 221 ions, which have the glycosyl-glycolaldehyde structures, were favored. Characteristic fragmentation patterns were observed for each m/z 221 ion from higher energy beam-type CID of 1-3 linked disaccharides and the stereochemistry of the non-reducing sugar, together with the anomeric configuration, were successfully identified both with and without 18O-labeling of the reducing sugar carbonyl group.

  7. A dominant electron trap in molecular beam epitaxial InAlN lattice-matched to GaN

    NASA Astrophysics Data System (ADS)

    Pandey, Ayush; Bhattacharya, Aniruddha; Cheng, Shaobo; Botton, Gianluigi A.; Mi, Zetian; Bhattacharya, Pallab

    2018-04-01

    Deep levels in lattice-matched undoped and Si-doped InAlN/GaN grown by plasma-assisted molecular beam epitaxy have been identified and characterized by capacitance and photocapacitance measurements. From x-ray diffraction, reflectance measurements, electron energy loss spectroscopy and high-resolution transmission electron microscopy it is evident that the material has two distinct phases with different compositions. These correspond to In compositions of 18.1% and 25.8%, with corresponding bandgaps of 4.6 eV and 4.1 eV, respectively. The lower bandgap material is present as columnar microstructures in the form of quantum wires. A dominant electron trap with an activation energy of 0.293  ±  0.01 eV, a small capture cross-section of (1.54  ±  0.25)  ×  10-18 cm2, and density increasing linearly with Si doping density is identified in all the samples. The characteristics of the electron trap and variation of diode capacitance are discussed in the context of carrier dynamics involving the dominant trap level and the quantum wires.

  8. Microstructural control of charge transport in organic blend thin-film transistors

    DOE PAGES

    Hunter, Simon; Chen, Jihua; Anthopoulos, Thomas D.

    2014-07-17

    In this paper, the charge-transport processes in organic p-channel transistors based on the small-molecule 2,8-difluoro-5,11-bis(triethylsilylethynyl)anthradithiophene (diF-TES ADT), the polymer poly(triarylamine)(PTAA) and blends thereof are investigated. In the case of blend films, lateral conductive atomic force microscopy in combination with energy filtered transmission electron microscopy are used to study the evolution of charge transport as a function of blends composition, allowing direct correlation of the film's elemental composition and morphology with hole transport. Low-temperature transport measurements reveal that optimized blend devices exhibit lower temperature dependence of hole mobility than pristine PTAA devices while also providing a narrower bandgap trap distribution thanmore » pristine diF-TES ADT devices. These combined effects increase the mean hole mobility in optimized blends to 2.4 cm 2/Vs; double the value measured for best diF-TES ADT-only devices. The bandgap trap distribution in transistors based on different diF-TES ADT:PTAA blend ratios are compared and the act of blending these semiconductors is seen to reduce the trap distribution width yet increase the average trap energy compared to pristine diF-TES ADT-based devices. In conclusion, our measurements suggest that an average trap energy of <75 meV and a trap distribution of <100 meV is needed to achieve optimum hole mobility in transistors based on diF-TES ADT:PTAA blends.« less

  9. Experiments with trapped ions and ultrafast laser pulses

    NASA Astrophysics Data System (ADS)

    Johnson, Kale Gifford

    Since the dawn of quantum information science, laser-cooled trapped atomic ions have been one of the most compelling systems for the physical realization of a quantum computer. By applying qubit state dependent forces to the ions, their collective motional modes can be used as a bus to realize entangling quantum gates. Ultrafast state-dependent kicks [1] can provide a universal set of quantum logic operations, in conjunction with ultrafast single qubit rotations [2], which uses only ultrafast laser pulses. This may present a clearer route to scaling a trapped ion processor [3]. In addition to the role that spin-dependent kicks (SDKs) play in quantum computation, their utility in fundamental quantum mechanics research is also apparent. In this thesis, we present a set of experiments which demonstrate some of the principle properties of SDKs including ion motion independence (we demonstrate single ion thermometry from the ground state to near room temperature and the largest Schrodinger cat state ever created in an oscillator), high speed operations (compared with conventional atom-laser interactions), and multi-qubit entanglement operations with speed that is not fundamentally limited by the trap oscillation frequency. We also present a method to provide higher stability in the radial mode ion oscillation frequencies of a linear radiofrequency (rf) Paul trap-a crucial factor when performing operations on the rf-sensitive modes. Finally, we present the highest atomic position sensitivity measurement of an isolated atom to date of 0.5 nm Hz. (-1/2) with a minimum uncertaintyof 1.7 nm using a 0.6 numerical aperature (NA) lens system, along with a method to correct aberrations and a direct position measurement of ion micromotion (the inherent oscillations of an ion trapped in an oscillating rf field). This development could be used to directly image atom motion in the quantum regime, along with sensing forces at the yoctonewton [10. (-24) N)] scale forgravity sensing, and 3D imaging of atoms from static to higher frequency motion. These ultrafast atomic qubit manipulation tools demonstrate inherent advantages over conventional techniques, offering a fundamentally distinct regime of control and speed not previously achievable.

  10. Entanglement-Based dc Magnetometry with Separated Ions*

    NASA Astrophysics Data System (ADS)

    Ruster, T.; Kaufmann, H.; Luda, M. A.; Kaushal, V.; Schmiegelow, C. T.; Schmidt-Kaler, F.; Poschinger, U. G.

    2017-07-01

    We demonstrate sensing of inhomogeneous dc magnetic fields by employing entangled trapped ions, which are shuttled in a segmented Paul trap. As sensor states, we use Bell states of the type |↑↓ ⟩ +ei φ|↓↑ ⟩ encoded in two 40Ca+ ions stored at different locations. The linear Zeeman effect leads to the accumulation of a relative phase φ , which serves for measuring the magnetic-field difference between the constituent locations. Common-mode magnetic-field fluctuations are rejected by the entangled sensor state, which gives rise to excellent sensitivity without employing dynamical decoupling and therefore enables accurate dc sensing. Consecutive measurements on sensor states encoded in the S1 /2 ground state and in the D5 /2 metastable state are used to separate an ac Zeeman shift from the linear dc Zeeman effect. We measure magnetic-field differences over distances of up to 6.2 mm, with accuracies down to 300 fT and sensitivities down to 12 pT /√{Hz }. Our sensing scheme features spatial resolutions in the 20-nm range. For optimizing the information gain while maintaining a high dynamic range, we implement an algorithm for Bayesian frequency estimation.

  11. Fostered Thermomagnetic Stabilities and Boosted Mechanical Reliability Related to High Trapped Field in Composite Bulk YBa2Cu3O(7-δ) Cryomagnets.

    PubMed

    Kenfaui, Driss; Sibeud, Pierre-Frédéric; Gomina, Moussa; Louradour, Eric; Chaud, Xavier; Noudem, Jacques G

    2015-08-06

    In the quest of YBa2Cu3O(7-δ) (Y123) bulk superconductors providing strong magnetic fields without failure, it is of paramount importance to achieve high thermal stabilities to safeguard the magnetic energy inside them during the trapping-field process, and sufficient mechanical reliability to withstand the stresses derived from the Lorenz force. Herein, we experimentally demonstrate a temperature rise induced by dissipative flux motion inside an Y123 thin-wall superconductor, and a significant thermal exchange in a composite bulk Y123 cryomagnet realized by embedding this superconductor with high thermal-conductivity metal network. It resulted in stimulating the maximum trapped field Bm, which reached 6.46 T on 15.9 mm-diameter single disk superconductor after magnetization by field cooling to 17 K under 7 T, leading to an improvement of 18% compared to the thin-wall superconductor. The composite cryomagnet particularly revealed the potential to trap stronger fields if larger magnetic activation is available. By virtue of the pore-free and crack-free microstructure of this cryomagnet, its strength σR was estimated to be 363 MPa, the largest one obtained so far for Y123 bulk superconductors, thus suggesting a striking mechanical reliability that seems to be sufficient to sustain stresses derived from trapped fields stronger than any values hitherto reported.

  12. The Role of Traps in the Microstructural Control of Hydrogen Embrittlement of Steels.

    DTIC Science & Technology

    1984-04-01

    which hydrogen interacts with precipitate or other particles located on or near different structural features can in many cases directly control the...growth, can be and have been used to reduce the extent of hydrogen embrittlement in a number of ferrous alloys , ranging from low strength...sulfide induced crack at the extremity of an elongated MnS particle . Hence, round shaped second phase particles are desirable, which are achievable by

  13. Measurement Of Hydrogen Capacities And Stability In Thin Films Of AlH Deposited By Magnetron Sputtering

    NASA Astrophysics Data System (ADS)

    Dissanayake, A.; AlFaify, S.; Garratt, E.; Nandasiri, M. I.; Taibu, R.; Tecos, G.; Hamdan, N. M.; Kayani, A.

    2011-06-01

    Thin, hydrogenated aluminum hydride films were deposited on silicon substrates using unbalanced magnetron (UBM) sputtering of a high purity aluminum target under electrically grounded conditions. Argon was used as sputtering gas and hydrogenation was carried out by diluting the growth plasma with hydrogen. The effect of hydrogen partial pressure on the final concentration of trapped elements including hydrogen has been studied using ion beam analysis (IBA) techniques. Moreover, in-situ thermal stability of trapped hydrogen in the film was carried out using Rutherford Backscattering Spectrometry (RBS), Non-Rutherford Backscattering Spectrometry (NRBS) and Elastic Recoil Detection Analysis (ERDA). Microstructure of the film was investigated by SEM analysis. Hydrogen content in the thin films was found decreasing as the films were heated above 110 °C in vacuum.

  14. 76 FR 37194 - Surety Companies Acceptable on Federal Bonds; Change in State of Incorportation, Business Address...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... State of Incorportation, Business Address and Phone; St. Paul Fire and Marine Insurance Company; St. Paul Guardian Insurance Company; St. Paul Mercury Insurance Company AGENCY: Financial Management... that St. Paul Fire and Marine Insurance Company (24767), St. Paul Guardian Insurance Company (24775...

  15. Upgrade of the SPIRAL identification station for high-precision measurements of nuclear β decay

    NASA Astrophysics Data System (ADS)

    Grinyer, G. F.; Thomas, J. C.; Blank, B.; Bouzomita, H.; Austin, R. A. E.; Ball, G. C.; Bucaille, F.; Delahaye, P.; Finlay, P.; Frémont, G.; Gibelin, J.; Giovinazzo, J.; Grinyer, J.; Kurtukian-Nieto, T.; Laffoley, A. T.; Leach, K. G.; Lefèvre, A.; Legruel, F.; Lescalié, G.; Perez-Loureiro, D.

    2014-03-01

    The low-energy identification station at SPIRAL (Système de Production d'Ions Radioactifs Accélérés en Ligne) has been upgraded for studying the β decays of short-lived radioactive isotopes and to perform high-precision half-life and branching-ratio measurements for superallowed Fermi and isospin T=1/2 mirror β decays. These new capabilities, combined with an existing Paul trap setup for measurements of β-ν angular-correlation coefficients, provide a powerful facility for investigating fundamental properties of the electroweak interaction through nuclear β decays. A detailed description of the design study, construction, and first results obtained from an in-beam commissioning experiment on the β+ decays 14 O and 17F are presented.

  16. Melem-based derivatives as metal-free photocatalysts for simultaneous reduction of Cr(VI) and degradation of 5-Sulfosalicylic acid.

    PubMed

    Lan, Huachun; Li, Lili; Liu, Huijuan; An, Xiaoqiang; Liu, Fei; Chen, Cuibai; Qu, Jiuhui

    2017-12-01

    Carbon nitride has been considered as promising metal-free polymers for low-cost photocatalysis. Most prevailing concern about this fantastic material focuses on g-C 3 N 4 , while the potential of other derivatives have been overlooked. Herein, in order to determine the desired derivatives for environmental pollutant treatment, the impact of degree of thermal polymerization on the microstructure of carbon nitride was investigated. Interestingly, melem-based derivatives exhibit 4- and 6-fold enhanced activities than g-C 3 N 4 , when used as synergetic photocatalysts for the simultaneous treatment of heavy metal ions and organic contaminants. According to the fundamental study of reactive species formation, a microstructure-dependent photocatalytic mechanism was established. Hydrogen bond-facilitated trapping of photogenerated holes and superior ability for oxygen molecular activation contributed to the high-performance of melem-based derivatives. In contrast, g-C 3 N 4 shows inferior performance during superoxide radical-dominated photodegradation reactions, as its microstructure is favorable for the generation of . Our research not only sheds new insights into the microstructure design of metal-free carbon nitride photocatalysts, but also has immense scientific and technological values for high-efficiency and synergetic environmental applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Planning and Problem Solving

    DTIC Science & Technology

    1982-10-01

    Artificial Intelig ~ence (Vol. III, edited by Paul R. Cohen and’ Edward A.. Feigenbaum)’, The chapter was written B’ Paul Cohen, with contributions... Artificial Intelligence (Vol. III, edited by Paul R. Cohen and EdWard A. Feigenbaum). The chapter was written by Paul R. Cohen, with contributions by Stephen...Wheevoats"EntermdI’ Planning and Problem ’Solving by Paul R. Cohen Chaptb-rXV-of Volumec III’of the Handbook of Artificial Intelligence edited by Paul R

  18. Dielectrophoretic capture of low abundance cell population using thick electrodes.

    PubMed

    Marchalot, Julien; Chateaux, Jean-François; Faivre, Magalie; Mertani, Hichem C; Ferrigno, Rosaria; Deman, Anne-Laure

    2015-09-01

    Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particles, C-PDMS allows the easy and fast integration of conductive microstructures using a soft-lithography approach while preserving O2 plasma bonding properties of PDMS substrate and avoiding a cumbersome alignment procedure. Here, we first performed numerical simulations to demonstrate the advantage of such thick C-PDMS electrodes over a coplanar electrode configuration. It is well established that dielectrophoretic force ([Formula: see text]) decreases quickly as the distance from the electrode surface increases resulting in coplanar configuration to a low trapping efficiency at high flow rate. Here, we showed quantitatively that by using electrodes as thick as a microchannel height, it is possible to extend the DEP force influence in the whole volume of the channel compared to coplanar electrode configuration and maintaining high trapping efficiency while increasing the throughput. This model was then used to numerically optimize a thick C-PDMS electrode configuration in terms of trapping efficiency. Then, optimized microfluidic configurations were fabricated and tested at various flow rates for the trapping of MDA-MB-231 breast cancer cell line. We reached trapping efficiencies of 97% at 20 μl/h and 78.7% at 80 μl/h, for 100 μm thick electrodes. Finally, we applied our device to the separation and localized trapping of CTCs (MDA-MB-231) from a red blood cells sample (concentration ratio of 1:10).

  19. Influence of Powder Outgassing Conditions on the Chemical, Microstructural, and Mechanical Properties of a 14 wt% Cr Ferritic ODS Steel

    NASA Astrophysics Data System (ADS)

    Sornin, D.; Giroux, P.-F.; Rigal, E.; Fabregue, D.; Soulas, R.; Hamon, D.

    2017-11-01

    Oxide dispersion-strengthened ferritic stainless steels are foreseen as fuel cladding tube materials for the new generation of sodium fast nuclear reactors. Those materials, which exhibit remarkable creep properties at high temperature, are reinforced by a dense precipitation of nanometric oxides. This precipitation is obtained by mechanical alloying of a powder and subsequent consolidation. Before consolidation, to obtain a fully dense material, the powder is vacuumed to outgas trapped gases and species adsorbed at the surface of the powder particles. This operation is commonly done at moderate to high temperature to evacuate as much as possible volatile species. This paper focuses on the influence of outgassing conditions on some properties of the further consolidated materials. Chemical composition and microstructural characterization of different materials obtained from various outgassing cycles are compared. Finally, impact toughness of those materials is evaluated by using Charpy testing. This study shows a significant influence of the outgassing conditions on the mechanical properties of the consolidated material. However, microstructure and oxygen contents seem poorly impacted by the various outgassing conditions.

  20. Mechanism for suppression of radiation-induced segregation by oversized solute addition in austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Hackett, Micah Jeremiah

    The objective of this thesis is to quantify the effect of oversized solutes on radiation-induced segregation in austenitic stainless steels and to determine the mechanism of this effect. Zr or Hf additions to austenitic stainless steels demonstrated a reduction in radiation-induced segregation of Cr and Ni at the grain boundary after proton irradiation at 400°C and 500°C to low doses, but the solute effect disappeared at higher doses. Rate theory modeling of RIS was extended to incorporate a solute-vacancy trapping mechanism to predict the effect of solutes on RIS. The model showed that RIS is most sensitive to the solute-vacancy binding energy. First principles calculations were used to determine a binding energy of 1.08 eV for Zr and 0.71 eV for Hf. Model and experiment agreed in showing suppression of Cr depletion at doses of 3 dpa at 400°C and 1 dpa at 500°C, and experimental results were consistent with the model in showing greater effectiveness of Zr relative to Hf due to a larger binding energy. The dislocation loop microstructure was measured at 400°C, 3 and 7 dpa, and a significant decrease in loop density and total loop line length in the oversized solute alloys relative to the reference alloys. The loop microstructure results were consistent with RIS results by confirming enhanced recombination of point defects by solute-vacancy trapping. Increases in RIS with dose indicated a loss of solute effectiveness, which was consistent with an observed increase in loop line length from 3 to 7 dpa. The loss of solute effectiveness at high dose is attributed to a loss of oversized solute from the matrix due to coarsening of carbide precipitates. X-ray diffraction identified a microstructure with ZrC or HfC precipitates prior to irradiation. Precipitate coarsening was identified as the most likely mechanism for the loss of solute effectiveness on RIS by the following: (1) diffusion analysis suggested significant solute diffusion by the vacancy flux to precipitate surfaces on the time scales of proton irradiations, and (2) atom probe measurements confirmed the loss of oversized solute in solution as a function of irradiation dose. RIS measurements and subsequent analyses were consistent with the solute-vacancy trapping process as the mechanism for enhanced recombination and suppression of RIS.

  1. New gelling systems to fabricate complex-shaped transparent ceramics

    NASA Astrophysics Data System (ADS)

    Yang, Yan; Wu, Yiquan

    2013-06-01

    The aim of this work was to prepare transparent ceramics with large size and complex-shapes by a new water-soluble gelling agent poly(isobutylene-alt-maleic anhydride). Alumina was used as an example of the application of the new gelling system. A stable suspension with 38vol% was prepared by ball milling. Trapped bubbles were removed before casting to obtain homogenous green bodies. The microstructure and particle distribution of alumina raw material were tested. The thermal behavior of the alumina green body was investigated, which exhibited low weight loss when compared with other gelling processes. The influence of solid loading and gelling agent addition were studied on the basis of rheological behavior of the suspension. The microstructures of alumina powders, green bodies before and after de-bindering process, were compared to understand the gelling condition between alumina particles and gelling agent.

  2. Effect of Microstructure and Trapping on the Hydrogen Embrittlement Susceptibility of a Ti-Bearing HSLA Steel.

    DTIC Science & Technology

    1984-11-01

    role of the carbide formers Mo. V. and Cr and the sequence of precipitation on transition temperature and fracture mode in a series of steels . In all... precipitation hardening in 11 microalloyed steels to Ashby-Orowan model. Figure 2-5: Schematic form of environmental cracking kinetics showing three 23...in steel are Ti solute additions and Ti precipitates . A direct connection between Ti and decreased susceptibility was apparently first established by

  3. The influence of isomer purity on trap states and performance of organic thin-film transistors.

    PubMed

    Diemer, Peter J; Hayes, Jacori; Welchman, Evan; Hallani, Rawad; Pookpanratana, Sujitra J; Hacker, Christina A; Richter, Curt A; Anthony, John E; Thonhauser, Timo; Jurchescu, Oana D

    2017-01-01

    Organic field-effect transistor (OFET) performance is dictated by its composition and geometry, as well as the quality of the organic semiconductor (OSC) film, which strongly depends on purity and microstructure. When present, impurities and defects give rise to trap states in the bandgap of the OSC, lowering device performance. Here, 2,8-difluoro-5,11-bis(triethylsilylethynyl)-anthradithiophene is used as a model system to study the mechanism responsible for performance degradation in OFETs due to isomer coexistence. The density of trapping states is evaluated through temperature dependent current-voltage measurements, and it is discovered that OFETs containing a mixture of syn - and anti -isomers exhibit a discrete trapping state detected as a peak located at ~ 0.4 eV above the valence-band edge, which is absent in the samples fabricated on single-isomer films. Ultraviolet photoelectron spectroscopy measurements and density functional theory calculations do not point to a significant difference in electronic band structure between individual isomers. Instead, it is proposed that the dipole moment of the syn -isomer present in the host crystal of the anti -isomer locally polarizes the neighboring molecules, inducing energetic disorder. The isomers can be separated by applying gentle mechanical vibrations during film crystallization, as confirmed by the suppression of the peak and improvement in device performance.

  4. Microfabricated Renewable Beads-Trapping/Releasing Flow Cell for Rapid Antigen-Antibody Reaction in Chemiluminescent Immunoassay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fu, Zhifeng; Shao, Guocheng; Wang, Jun

    2011-04-01

    A filter pillar-array microstructure was coupled with a pneumatic micro-valve to fabricate a reusable miniaturized beads-trapping/releasing flow cell, in which trapping and releasing beads can be conveniently realized by switching the micro-valve. This miniaturized device was suitable to construct automatic fluidic system for “renewable surface analysis”. The renewable surface strategy based on pneumatic micro-valve enabled capture of beads in beads chamber prior to each assay, and release of the used beads after the assay. Chemiluminescent competitive immunoassay of 3,5,6-trichloropyridinol (TCP) was performed as a model to demonstrate the application potential of this reusable miniaturized flow cell. The whole fluidic assaymore » process including beads trapping, immuno-binding, beads washing, beads releasing and signal collection could be completed in 10 min. Immunoassay of TCP using this miniaturized device showed a linear range of 0.20-70 ng/mL with a limit of detection of 0.080 ng/mL. The device had been successfully used for detection of TCP spiked in rat serum with average recovery of 97%. This investigation provides a rapid, sensitive, reusable, low-cost and automatic miniaturized device for solid-phase biochemical analysis for various purposes.« less

  5. Cracks growth behaviors of commercial pure titanium under nanosecond laser irradiation for formation of nanostructure-covered microstructures (with sub-5-μm)

    NASA Astrophysics Data System (ADS)

    Pan, A. F.; Wang, W. J.; Mei, X. S.; Zheng, B. X.; Yan, Z. X.

    2016-11-01

    This study reported on the formation of sub-5-μm microstructures covered on titanium by cracks growth under 10-ns laser radiation at the wavelength of 532 nm and its induced light modification for production of nanostructures. The electric field intensity and laser power density absorbed by commercial pure titanium were computed to investigate the self-trapping introduced by cracks and the effect of surface morphology on laser propagation characteristics. It is found that nanostructures can form at the surface with the curvature radius below 20 μm. Meanwhile, variable laser fluences were applied to explore the evolution of cracks on commercial pure titanium with or without melt as spot overlap number increased. Experimental study was first performed at the peak laser fluence of 1.063 J/cm2 to investigate the microstructures induced only by cracks growth. The results demonstrated that angular microstructures with size between 1.68 μm and 4.74 μm was obtained and no nanostructure covered. Then, at the peak laser fluence of 2.126 J/cm2, there were some nanostructures covered on the melt-induced curved microstructured surface. However, surface molten material submerged in the most of cracks at the spot overlap number of 744, where the old cracks disappeared. The results indicated that there was too much molten material and melting time at the peak laser fluence of 2.126 J/cm2, which was not suitable for obtainment of perfect micro-nano structures. On this basis, peak laser fluence was reduced down to 1.595 J/cm2 and the sharp sub-5 μm microstructures with nanostructures covered was obtained at spot overlap number of 3720.

  6. Electronegativity Equalization with Pauling Units.

    ERIC Educational Resources Information Center

    Bratsch, Steven G.

    1984-01-01

    Discusses electronegativity equalization using Pauling units. Although Pauling has qualitatively defined electronegativity as the power of an atom in a molecule to attract electrons to itself, Pauling electronegativities are treated in this paper as prebonded, isolated-atom quantities. (JN)

  7. Ejection of Coulomb Crystals from a Linear Paul Ion Trap for Ion-Molecule Reaction Studies.

    PubMed

    Meyer, K A E; Pollum, L L; Petralia, L S; Tauschinsky, A; Rennick, C J; Softley, T P; Heazlewood, B R

    2015-12-17

    Coulomb crystals are being increasingly employed as a highly localized source of cold ions for the study of ion-molecule chemical reactions. To extend the scope of reactions that can be studied in Coulomb crystals-from simple reactions involving laser-cooled atomic ions, to more complex systems where molecular reactants give rise to multiple product channels-sensitive product detection methodologies are required. The use of a digital ion trap (DIT) and a new damped cosine trap (DCT) are described, which facilitate the ejection of Coulomb-crystallized ions onto an external detector for the recording of time-of-flight (TOF) mass spectra. This enables the examination of reaction dynamics and kinetics between Coulomb-crystallized ions and neutral molecules: ionic products are typically cotrapped, thus ejecting the crystal onto an external detector reveals the masses, identities, and quantities of all ionic species at a selected point in the reaction. Two reaction systems are examined: the reaction of Ca(+) with deuterated isotopologues of water, and the charge exchange between cotrapped Xe(+) with deuterated isotopologues of ammonia. These reactions are examples of two distinct types of experiment, the first involving direct reaction of the laser-cooled ions, and the second involving reaction of sympathetically-cooled heavy ions to form a mixture of light product ions. Extensive simulations are conducted to interpret experimental results and calculate optimal operating parameters, facilitating a comparison between the DIT and DCT approaches. The simulations also demonstrate a correlation between crystal shape and image shape on the detector, suggesting a possible means for determining crystal geometry for nonfluorescing ions.

  8. Energy Scaling of Cold Atom-Atom-Ion Three-Body Recombination

    NASA Astrophysics Data System (ADS)

    Krükow, Artjom; Mohammadi, Amir; Härter, Arne; Denschlag, Johannes Hecker; Pérez-Ríos, Jesús; Greene, Chris H.

    2016-05-01

    We study three-body recombination of Ba++Rb +Rb in the mK regime where a single 138Ba+ ion in a Paul trap is immersed into a cloud of ultracold 87Rb atoms. We measure the energy dependence of the three-body rate coefficient k3 and compare the results to the theoretical prediction, k3∝Ecol-3 /4, where Ecol is the collision energy. We find agreement if we assume that the nonthermal ion energy distribution is determined by at least two different micromotion induced energy scales. Furthermore, using classical trajectory calculations we predict how the median binding energy of the formed molecules scales with the collision energy. Our studies give new insights into the kinetics of an ion immersed in an ultracold atom cloud and yield important prospects for atom-ion experiments targeting the s -wave regime.

  9. Two-point active microrheology in a viscous medium exploiting a motional resonance excited in dual-trap optical tweezers

    NASA Astrophysics Data System (ADS)

    Paul, Shuvojit; Kumar, Randhir; Banerjee, Ayan

    2018-04-01

    Two-point microrheology measurements from widely separated colloidal particles approach the bulk viscosity of the host medium more reliably than corresponding single-point measurements. In addition, active microrheology offers the advantage of enhanced signal to noise over passive techniques. Recently, we reported the observation of a motional resonance induced in a probe particle in dual-trap optical tweezers when the control particle was driven externally [Paul et al., Phys. Rev. E 96, 050102(R) (2017), 10.1103/PhysRevE.96.050102]. We now demonstrate that the amplitude and phase characteristics of the motional resonance can be used as a sensitive tool for active two-point microrheology to measure the viscosity of a viscous fluid. Thus, we measure the viscosity of viscous liquids from both the amplitude and phase response of the resonance, and demonstrate that the zero crossing of the phase response of the probe particle with respect to the external drive is superior compared to the amplitude response in measuring viscosity at large particle separations. We compare our viscosity measurements with those using a commercial rheometer and obtain an agreement ˜1 % . The method can be extended to viscoelastic material where the frequency dependence of the resonance may provide further accuracy for active microrheological measurements.

  10. FeOx-TiO2 Film with Different Microstructures Leading to Femtosecond Transients with Different Properties: Biological Implications under Visible Light

    PubMed Central

    Rtimi, Sami; Pulgarin, Cesar; Nadtochenko, Victor A.; Gostev, Fedor E.; Shelaev, Ivan V.; Kiwi, John

    2016-01-01

    This study presents the first report addressing the effect of FeOx-TiO2 films microstructure on the transients detected by fast spectroscopy related to the long-range bacterial inactivation performance. The different fast kinetic femtosecond transient spectroscopy is reported for each FeOx+TiO2 microstructure. The lifetime of the short transient-species and the oxidative intermediate radicals generated under light were identified. Co-sputtered FeOx-TiO2 on polyethylene films presenting random distribution for both oxides were compared with sequentially sputtered FeOx/TiO2 films made up only by FeOx in the topmost layers. The ratio FeOx:TiO2 was optimized to attain the highest photo-conversion. By X-ray fluorescence, the Fe:Ti ration was found to be ~1.4 in the film bulk and by XPS-etching a ratio of 4:1 was found on the photocatalyst top-most layers. For co-sputtered FeOx-TiO2-PE films, the FeOx-TiO2 heterojunction led to electron injection from the FeOx to lower-lying TiO2 trapping states. The film optical properties, particle size, roughness, hydrophobic-hydrophilic shift and temporal evolution of the transient redox states were characterized in detail. Films with different microstructure led to different antibacterial activity. This suggests that the FeOx-TiO2-PE microstructure and not the position of the potential energy level of the semiconductors FeOx and TiO2 control the charge transfer under light irradiation. PMID:27443505

  11. FeOx-TiO2 Film with Different Microstructures Leading to Femtosecond Transients with Different Properties: Biological Implications under Visible Light.

    PubMed

    Rtimi, Sami; Pulgarin, Cesar; Nadtochenko, Victor A; Gostev, Fedor E; Shelaev, Ivan V; Kiwi, John

    2016-07-22

    This study presents the first report addressing the effect of FeOx-TiO2 films microstructure on the transients detected by fast spectroscopy related to the long-range bacterial inactivation performance. The different fast kinetic femtosecond transient spectroscopy is reported for each FeOx+TiO2 microstructure. The lifetime of the short transient-species and the oxidative intermediate radicals generated under light were identified. Co-sputtered FeOx-TiO2 on polyethylene films presenting random distribution for both oxides were compared with sequentially sputtered FeOx/TiO2 films made up only by FeOx in the topmost layers. The ratio FeOx:TiO2 was optimized to attain the highest photo-conversion. By X-ray fluorescence, the Fe:Ti ration was found to be ~1.4 in the film bulk and by XPS-etching a ratio of 4:1 was found on the photocatalyst top-most layers. For co-sputtered FeOx-TiO2-PE films, the FeOx-TiO2 heterojunction led to electron injection from the FeOx to lower-lying TiO2 trapping states. The film optical properties, particle size, roughness, hydrophobic-hydrophilic shift and temporal evolution of the transient redox states were characterized in detail. Films with different microstructure led to different antibacterial activity. This suggests that the FeOx-TiO2-PE microstructure and not the position of the potential energy level of the semiconductors FeOx and TiO2 control the charge transfer under light irradiation.

  12. FeOx-TiO2 Film with Different Microstructures Leading to Femtosecond Transients with Different Properties: Biological Implications under Visible Light

    NASA Astrophysics Data System (ADS)

    Rtimi, Sami; Pulgarin, Cesar; Nadtochenko, Victor A.; Gostev, Fedor E.; Shelaev, Ivan V.; Kiwi, John

    2016-07-01

    This study presents the first report addressing the effect of FeOx-TiO2 films microstructure on the transients detected by fast spectroscopy related to the long-range bacterial inactivation performance. The different fast kinetic femtosecond transient spectroscopy is reported for each FeOx+TiO2 microstructure. The lifetime of the short transient-species and the oxidative intermediate radicals generated under light were identified. Co-sputtered FeOx-TiO2 on polyethylene films presenting random distribution for both oxides were compared with sequentially sputtered FeOx/TiO2 films made up only by FeOx in the topmost layers. The ratio FeOx:TiO2 was optimized to attain the highest photo-conversion. By X-ray fluorescence, the Fe:Ti ration was found to be ~1.4 in the film bulk and by XPS-etching a ratio of 4:1 was found on the photocatalyst top-most layers. For co-sputtered FeOx-TiO2-PE films, the FeOx-TiO2 heterojunction led to electron injection from the FeOx to lower-lying TiO2 trapping states. The film optical properties, particle size, roughness, hydrophobic-hydrophilic shift and temporal evolution of the transient redox states were characterized in detail. Films with different microstructure led to different antibacterial activity. This suggests that the FeOx-TiO2-PE microstructure and not the position of the potential energy level of the semiconductors FeOx and TiO2 control the charge transfer under light irradiation.

  13. Lattice defects affecting moisture-induced embrittlement of Ni-based L1{sub 2} ordered intermetallics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Takasugi, T.; Hanada, S.

    1997-12-31

    Moisture-induced embrittlement of L1{sub 2} alloys (such as Ni{sub 3}(Si,Ti) and Ni{sub 3}Al) is observed by tensile test and SEM fractography. A variety of microstructures were prepared by selecting pre-deformation and heat treatment conditions. It is shown that tensile ductility and the associated fractography depend on structure as well as test atmosphere. Well-annealed specimens are susceptible to moisture-induced embrittlement while pre-deformed specimens are resistive to moisture-induced embrittlement. Also, this embrittlement is generally sensitive to the heat treatment scheme preceded by the pre-deformation. Results indicate that the embrittlement occurs when hydrogen is enriched on grain boundaries. On the other hand, themore » embrittlement can be suppressed when hydrogen is trapped at lattice defects such as dislocations and vacancies. These results are discussed in association with the kinetics of hydrogen in the pre-deformed microstructure.« less

  14. 40 CFR 81.27 - Minneapolis-St. Paul Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Minneapolis-St. Paul Intrastate Air... Air Quality Control Regions § 81.27 Minneapolis-St. Paul Intrastate Air Quality Control Region. The Minneapolis-St. Paul Intrastate Air Quality Control Region (Minnesota) consists of the territorial area...

  15. 75 FR 27494 - Proposed Amendment of Class E Airspace; Pauls Valley, OK

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ... 0182; Airspace Docket No. 10-ASW-4] Proposed Amendment of Class E Airspace; Pauls Valley, OK AGENCY... action proposes to amend Class E airspace at Pauls Valley, OK. Additional controlled airspace is necessary to accommodate new Standard Instrument Approach Procedures (SIAPs) at Pauls Valley Municipal...

  16. The effect of hydrogen and microstructure on the deformation and fracture behavior of a single crystal nickel-base superalloy. Final Report Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Walston, William S.

    1990-01-01

    A study was conducted on the effects of internal hydrogen and microstructure on the deformation and fracture of a single crystal nickel-base superalloy. In particular, room temperature plane strain fracture toughness and tensile tests were performed on hydrogen-free and hydrogen charged samples of PWA 1480. The role of microstructure was incorporated by varying the levels of porosity and eutectic gamma/gamma prime through hot isostatic pressing and heat treatment. The room temperature behavior of PWA 1480 was unusual because precipitate shearing was not the primary deformation mechanism at all strains. At strains over 1 percent, dislocations were trapped in the gamma matrix and an attempt was made to relate this behavior to compositional differences between PWA 1480 and other superalloys. Another unique feature of the tensile behavior was cleavage of the eutectic gamma/gamma prime, which is believed to initiate the failure process. Fracture occurred on (111) planes and is likely a result of shear localization along these planes. Elimination of the eutectic gamma/gamma prime greatly improved the tensile ductility, but pososity had no effect on tensile properties. Large quantities of hydrogen (1.74 at. percent) were gas-phase charged into the material, but surprisingly this was not a function of the amount of porosity or eutectic gamma/gamma prime present. Desorption experiments suggest that the vast majority of hydrogen is at reversible lattice trapping sites. This large, uniform concentration of hydrogen dramatically reduced the tensile strain to failure, but only slightly affected the reduction in area. Available hydrogen embrittlement models were examined in light of these results and it was found that the hydrogen enhanced localized plasticity model can explain much of the tensile behavior. K(IC) fracture toughness tests were conducted, but it was necessary to also perform J(IC) tests to provide valid data.

  17. Meandering Musings by Linus Pauling: "American Scientists and the Spirit of the Frontier".

    PubMed

    Bause, George S

    2016-04-01

    Hoping to raise funds in 1975 for his namesake institute, Linus Pauling submitted to Esquire magazine a 32-page handwritten manuscript, "American Scientists and the Spirit of the Frontier." Angered when his submission for publication was declined, Pauling eventually gifted the original manuscript in 1986 to his friend, Linus Pauling Institute fundraiser Stephen Maddox, who would sell it in 2004 to the Wood Library-Museum of Anesthesiology. Published accurately here for the first time, the manuscript captures not only Pauling's sweeping metaphor of scientists as frontiersmen but also the creative process by which Pauling formulated his hydrate microcrystal theory of general anesthesia. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Study of the micro-structural properties of RISUG--a newly developed male contraceptive.

    PubMed

    Kumar, Sunil; Roy, Sohini; Chaudhury, Koel; Sen, Prasenjit; Guha, Sujoy K

    2008-07-01

    A new male contraceptive given the name RISUG (an acronym for reversible inhibition of sperm under guidance) and presently undergoing advanced clinical trials has been developed. When injected into the lumen of the vas deferens, its polyelectrolytic nature induces a surface charge imbalance on sperm membrane system leading to the leakage of enzymes essential for fertilization. Contact mode atomic force microscopy (AFM) has been used to analyze quantitatively the micro-structural properties of RISUG and its precipitate in various systems. Hydrolysis of the contraceptive gel resulted in the formation of pores of varying dimensions. RISUG being a highly charged molecule, as evident from zeta potential measurements, has a tendency to form a complex with ionic biomolecules present in the seminal plasma. This is supported by the experimental observations using AFM. This RISUG-biomolecule complex possibly acts as an ionic trap for spermatozoa passing through the vas deferens. Micro-structural properties of RISUG including amplitude (root mean square, peak-to-valley distance, skewness and kurtosis) and spatial roughness have been studied to understand its response to various physiological conditions. Significant alterations in the surface charge distribution of the sperm cell is observed on exposure to RISUG. 2007 Wiley Periodicals, Inc.

  19. "Between the Heavens and the Earth": Narrating the Execution of Moses Paul

    ERIC Educational Resources Information Center

    Salyer, Matt

    2012-01-01

    The 1772 execution of the Mohegan sailor Moses Paul served as the occasion for Samson Occom's popular "Sermon," reprinted in numerous editions. Recent work by Ava Chamberlain seeks to recover Paul's version of events from contemporary court records. This article argues that Paul's "firsthand" account of the case and autobiographical narrative…

  20. Survival probability of diffusion with trapping in cellular neurobiology

    NASA Astrophysics Data System (ADS)

    Holcman, David; Marchewka, Avi; Schuss, Zeev

    2005-09-01

    The problem of diffusion with absorption and trapping sites arises in the theory of molecular signaling inside and on the membranes of biological cells. In particular, this problem arises in the case of spine-dendrite communication, where the number of calcium ions, modeled as random particles, is regulated across the spine microstructure by pumps, which play the role of killing sites, while the end of the dendritic shaft is an absorbing boundary. We develop a general mathematical framework for diffusion in the presence of absorption and killing sites and apply it to the computation of the time-dependent survival probability of ions. We also compute the ratio of the number of absorbed particles at a specific location to the number of killed particles. We show that the ratio depends on the distribution of killing sites. The biological consequence is that the position of the pumps regulates the fraction of calcium ions that reach the dendrite.

  1. Magnetic microstructures for regulating Brownian motion

    NASA Astrophysics Data System (ADS)

    Sooryakumar, Ratnasingham

    2013-03-01

    Nature has proven that it is possible to engineer complex nanoscale machines in the presence of thermal fluctuations. These biological complexes, which harness random thermal energy to provide functionality, yield a framework to develop related artificial, i.e., nonbiological, phenomena and devices. A major challenge to achieving positional control of fluid-borne submicron sized objects is regulating their Brownian fluctuations. In this talk a magnetic-field-based trap that regulates the thermal fluctuations of superparamagnetic beads in suspension will be presented. Local domain-wall fields originating from patterned magnetic wires, whose strength and profile are tuned by weak external fields, enable bead trajectories within the trap to be managed and easily varied between strong confinements and delocalized spatial excursions. Moreover, the frequency spectrum of the trapped bead responds to fields as a power-law function with a tunable, non-integer exponent. When extended to a cluster of particles, the trapping landscape preferentially stabilizes them into formations of 5-fold symmetry, while their Brownian fluctuations result in frequent transitions between different cluster configurations. The quantitative understanding of the Brownian dynamics together with the ability to tune the extent of the fluctuations enables the wire-based platform to serve as a model system to investigate the competition between random and deterministic forces. Funding from the U.S. Army Research Office under contract W911NF-10-1-0353 is acknowledged.

  2. A novel, two-step top seeded infiltration and growth process for the fabrication of single grain, bulk (RE)BCO superconductors

    NASA Astrophysics Data System (ADS)

    Namburi, Devendra K.; Shi, Yunhua; Palmer, Kysen G.; Dennis, Anthony R.; Durrell, John H.; Cardwell, David A.

    2016-09-01

    A fundamental requirement of the fabrication of high performing, (RE)-Ba-Cu-O bulk superconductors is achieving a single grain microstructure that exhibits good flux pinning properties. The top seeded melt growth (TSMG) process is a well-established technique for the fabrication of single grain (RE)BCO bulk samples and is now applied routinely by a number of research groups around the world. The introduction of a buffer layer to the TSMG process has been demonstrated recently to improve significantly the general reliability of the process. However, a number of growth-related defects, such as porosity and the formation of micro-cracks, remain inherent to the TSMG process, and are proving difficult to eliminate by varying the melt process parameters. The seeded infiltration and growth (SIG) process has been shown to yield single grain samples that exhibit significantly improved microstructures compared to the TSMG technique. Unfortunately, however, SIG leads to other processing challenges, such as the reliability of fabrication, optimisation of RE2BaCuO5 (RE-211) inclusions (size and content) in the sample microstructure, practical oxygenation of as processed samples and, hence, optimisation of the superconducting properties of the bulk single grain. In the present paper, we report the development of a near-net shaping technique based on a novel two-step, buffer-aided top seeded infiltration and growth (BA-TSIG) process, which has been demonstrated to improve greatly the reliability of the single grain growth process and has been used to fabricate successfully bulk, single grain (RE)BCO superconductors with improved microstructures and superconducting properties. A trapped field of ˜0.84 T and a zero field current density of 60 kA cm-2 have been measured at 77 K in a bulk, YBCO single grain sample of diameter 25 mm processed by this two-step BA-TSIG technique. To the best of our knowledge, this value of trapped field is the highest value ever reported for a sample fabricated by an infiltration and growth process. In this study we report the successful fabrication of 14 YBCO samples, with diameters of up to 32 mm, by this novel technique with a success rate of greater than 92%.

  3. 75 FR 67303 - Determinations of Attainment by the Applicable Attainment Date for the Hayden, Nogales, Paul Spur...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... of Attainment by the Applicable Attainment Date for the Hayden, Nogales, Paul Spur/Douglas PM 10... proposes to determine that the Hayden, Nogales, and Paul Spur/Douglas nonattainment areas in Arizona... Hayden, Nogales and Paul Spur/Douglas nonattainment areas are not currently attaining the PM 10 standard...

  4. 77 FR 41168 - Marine Mammals; Subsistence Taking of Northern Fur Seals; St. Paul Island

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-12

    ... Mammals; Subsistence Taking of Northern Fur Seals; St. Paul Island AGENCY: National Marine Fisheries... taking of northern fur seals on St. Paul Island. St. Paul's petition requests that NMFS revise the... seals; take a total of up to 3,000 fur seals annually compared to 2,000 currently allowed, including up...

  5. 78 FR 46938 - St. Paul Park Refining Co. LLC v. Enbridge Pipelines (North Dakota) LLC; Notice of Complaint

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-02

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. OR13-28-000] St. Paul Park..., 2013, St. Paul Park Refining Co. LLC (Complainant) filed a formal complaint against Enbridge Pipelines... regulatory basis. St. Paul Park Refining Co. LLC certifies that copies of the complaint were served on the...

  6. 75 FR 34097 - Expansion of Foreign-Trade Zone 119; Minneapolis-St. Paul Area

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1684] Expansion of Foreign-Trade Zone 119; Minneapolis-St. Paul Area Pursuant to its authority under the Foreign-Trade Zones Act of June 18... Sites 7 and 8 in the Minneapolis-St. Paul area, adjacent to the Minneapolis-St. Paul Customs and Border...

  7. "Dancing Cannot Start Too Soon": Spiritual Education in the Thought of Jean Paul Friedrich Richter

    ERIC Educational Resources Information Center

    Pridmore, John

    2004-01-01

    Johann Paul Friedrich Richter (1763-1825) adopted the pen-name "Jean Paul" in honour of Jean Jaques Rousseau. His "Levana or the doctrine of education" ("Levana oder Erziehlehre") was once a standard text and required reading in teacher education. Outside Germany the name of Jean Paul is now little known and the…

  8. 76 FR 43958 - Safety Zone; Rotary Club of Fort Lauderdale New River Raft Race, New River, Fort Lauderdale, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ... have questions on this proposed rule, call or e-mail Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A.Steiner@uscg.mil . If you have... Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A...

  9. Maniac Talk - Paul Newman

    NASA Image and Video Library

    2015-02-25

    Paul Newman Maniac Lecture, February 25, 2015 NASA climate scientist Dr. Paul Newman presented a Maniac Talk entitled "Some pretty good rules for a career: Newman's own lessons." Paul traced his journey from middle of Seattle, where he grew up, moved to rural Iowa for graduate school, and made his way to NASA/GSFC in 1984, and discussed lessons to be learned from the ozone depletion story.

  10. Atomic spectroscopy with twisted photons: Separation of M 1 -E 2 mixed multipoles

    NASA Astrophysics Data System (ADS)

    Afanasev, Andrei; Carlson, Carl E.; Solyanik, Maria

    2018-02-01

    We analyze atomic photoexcitation into the discrete states by twisted photons, or photons carrying extra orbital angular momentum along their direction of propagation. From the angular momentum and parity considerations, we are able to relate twisted-photon photoexcitation amplitudes to their plane-wave analogs, independently of the details of the atomic wave functions. We analyze the photoabsorption cross sections of mixed-multipolarity E 2 -M 1 transitions in ionized atoms and found fundamental differences coming from the photon topology. Our theoretical analysis demonstrates that it is possible to extract the relative transition rates of different multipolar contributions by measuring the photoexcitation rate as a function of the atom's position (or impact parameter) with respect to the optical vortex center. The proposed technique for separation of multipoles can be implemented if the target's atom position is resolved with subwavelength accuracy; for example, with Paul traps. Numerical examples are presented for Boron-like highly charged ions.

  11. Paul Frampton

    NASA Astrophysics Data System (ADS)

    Williams, Heather A.

    2013-01-01

    I was astonished by an article that appeared on physicsworld.com in November about the physicist Paul Frampton and his imprisonment for attempted cocaine smuggling ("Paul Frampton hit by 56-month drugs sentence", 22 November 2012).

  12. Linus Pauling and sickle cell disease.

    PubMed

    Eaton, William A

    2003-01-01

    The 1949 paper by Linus Pauling et al. [Science 110 (1949) 543-548] describing the discovery of sickle cell anemia as the first molecular disease had a major impact on biology and medicine. Inspired by the scholarly works of John Edsall on the history of hemoglobin research, I present a brief retrospective analysis of Pauling's paper. This is followed by some personal recollections of Edsall and Pauling.

  13. Alignment of olivine crystals during diffusion creep in oceanic peridotite mylonites

    NASA Astrophysics Data System (ADS)

    Deems, N. J.; Warren, J. M.; Wolfson-Schwehr, M.

    2014-12-01

    At small grain sizes (<10 µm), olivine is expected to deform by diffusion creep at lithospheric conditions. Microstructural analysis by electron backscatter diffraction of 13 peridotite mylonites from St. Paul's Rocks (SPR) indicates that olivine has a pronounced axial-[010] lattice preferred orientation (i.e. [010] clusters perpendicular to foliation, while [100] and [001] are dispersed in the foliation plane) and a mean grain size of ~7µm. Holtzman et al. (2003) has observed similar LPOs in partially molten samples experimentally deformed under simple shear at lithospheric conditions. The occurrence of a lattice preferred orientation (LPO) is typically interpreted as indicating deformation by dislocation creep. In addition, compositional maps of the samples show that amphibole (pargasite) is ubiquitous. As the presence of pargasite in peridotites is controlled in part by the activity of plagioclase and water at high temperatures (Lynkins and Jenkins, 1992), we infer this as evidence for the presence of pre- to syn-tectonic trapped melt. In order to explain the observed LPO in SPR mylonites, we evaluate the hypothesis that alignment occurred during diffusion creep, such as observed in experiments by Sundberg and Cooper (2008) and Miyazaki et al., (2013). To explore this hypothesis, we conducted analyses of low angle (2-10°) rotation axis inverse pole figures (IPFs), which can often provide insight into the operative slip system(s). Analyses of low angle IPFs from SPR, however, showed no definitive correlation to any one particular slip system. On the other hand, high angle IPFs showed intense clustering of rotational axes at 75-90° about [010], indicating that [100] and [001] align nearly perpendicular to [010]. Based on the IPF analysis and evidence of pre- to syn-tectonic melt, we conclude that the presence of melt lubricated grain boundaries, which resulted in rigid rotation of grains and alignment of the [010] axes controlled by the orthorhombic crystal habit of olivine. That is, as [010] is shortest in terms of habit, this allows [010] to align perpendicular to the shear plane, while the [100] and [001] axes are dispersed in the plane parallel to shear. Thus, SPR mylonites represent a natural example of olivine LPO formation during diffusion creep.

  14. Minneapolis-Saint Paul air cargo study

    DOT National Transportation Integrated Search

    2001-12-01

    The Minneapolis-Saint Paul Task Force commissioned this study. It was established to address the apparent decline in air cargo through Minneapolis-Saint Paul airport in recent years. Distribution services, especially international air cargo, are stra...

  15. The Effect of Organic Compounds on the Hygroscopic Properties of Inorganic Aerosol

    NASA Astrophysics Data System (ADS)

    Krieger, U. K.; Zardini, A. A.; Marcolli, C.

    2006-12-01

    The hygroscopicity of the aerosols plays a major role for the direct and indirect effect on the climate. It is known that aerosols are often a mixture of inorganic and organic matter. A significant fraction of the organic matter is water soluble (WSOC) and affects light scattering, water uptake and phase transitions of multicomponent aerosols. Additionally, organic matter can act as a surfactant around an inorganic particle, affecting the evaporation-condensation time scale. This research project benefits from the combined measurements performed by two different instrumentations: the electrodynamic trap at IACETH, Zürich, Switzerland, and a Tandem Differential Mobility Analizer (TDMA) at the Paul Scherrer Institute, Switzerland. The Electrodynamic Trap consists of a chamber in which a levitated particle can experience all the atmospherically relevant conditions of temperature, pressure, and humidity. All these parameters can be continuously varied so that the hygroscopic curve of the aerosol particle can be measured. Additional tools help to better characterize the aerosol particle: 90 degrees angular scattering of lasers (for radius measurements) and intensity fluctuation of the scattered light with time (for phase changes detection). In this poster the results obtained through the electrodynamic balance technique will be shown and compared with the TDMA. In particular, bicomponent ammonium sulphate with adipic acid bicomponent particles are studied, with different mixing ratios. Particular emphasis is put on assessing the water uptake and the phase changes of the particles.

  16. 58. Photographic copy of original construction plan (St. Paul Engineer's ...

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

    58. Photographic copy of original construction plan (St. Paul Engineer's Office, Wabasha St. Bridge, Plan of Masonry, February 1899); south abutment - Wabasha Street Bridge, Spanning Mississippi River at Wabasha Street, Saint Paul, Ramsey County, MN

  17. 76 FR 73666 - Notice of Inventory Completion: Paul H. Karshner Memorial Museum, Puyallup, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-29

    ..., 2011. ADDRESSES: Brian Fox, Director of Instructional Leadership, Puyallup School District, Paul H... criteria in 43 CFR 10.11(c)(1) should contact Brian Fox, Director of Instructional Leadership, Paul H...

  18. The Modern Catholic Just War Tradition

    DTIC Science & Technology

    2012-04-15

    offered a positive solution to the problems facing humanity. In fact in an address to the Vatican Diplomatic Corps, January 13, 2003, Pope John Paul II...cii Pope John Paul II. “Address of His Holiness Pope John Paul II to the Diplomatice Corps.” Speech to the Vatican Diplomatic Corps Libreria...the Vatican Diplomatic Corps Libreria Editrice Vaticana, January 2003. 4 http://www.vatican.va/holy_father/john_paul_ii/speeches/2003/january

  19. Les instabilités antérieures de l’épaule:à propos de 73 cas

    PubMed Central

    Jamal, Louaste; Bousbaa, Hicham; Cherrad, Taoufik; Wahidi, Mohammed; Amhajji, Larbi; Rachid, Khalid

    2016-01-01

    Entre 2005 et 2014, 73patients (77 épaules) ont bénéficié d’une intervention de Latarjet pour instabilité antérieure de l’épaule. Nous avons, rétrospectivement, évalué les résultats cliniques et radiologiques de cette technique opératoire. L’intervention a été réalisée pour le traitement d’une luxation récidivante dans 69 cas, subluxation récidivante douloureuse dans 5 cas et 3 épaules douloureuses Tous les patients ont eu une évaluation radiographique avant l’intervention et lors du contrôle le plus récent. Selon le score de Rowe, 73 (94.8 %) des 77 épaules ont obtenu un résultat bon ou excellent. Au plus grand recul, 74 épaules étaient indemnes d’arthrose glénohumérale. PMID:27800066

  20. Treatment of nasal fractures by Paul of Aegina.

    PubMed

    Skoulakis, Charalampos E; Manios, Andreas G; Theos, Evangelos A; Papadakis, Chariton E; Stavroulaki, Pelagia S

    2008-03-01

    The most exact description of the management of nasal fractures given by any physician of ancient times belongs to Paul of Aegina (AD 625-690). The goal of this article is to describe the therapeutic methods and surgical techniques used by Paul of Aegina in the treatment of nasal injuries. We studied the original Greek texts and the translation published in Venice, titled "The seven books of excellent doctor Paul of Aegina." The sixth book of his medical compendium is devoted to surgery. We identified the treatments and techniques applied to the restoration of injured noses. In this historical article we present the management of nasal fractures by Paul of Aegina. Paul of Aegina's conservative and surgical management for each form of injury was adopted by later physicians and influenced European medicine, a management surprisingly identical with the way nasal fractures are managed nowadays.

  1. Effect of pH on the microstructure of β-Ga2O3 and its enhanced photocatalytic activity for antibiotic degradation.

    PubMed

    Liu, Jin; Lu, Wei; Zhong, Qian; Wu, Hongzhang; Li, Yunlin; Li, Lili; Wang, Zhenling

    2018-06-01

    Semiconductor photocatalysis has become the focus of recent research on antibiotic treatment because it is a green and efficient technology. In this study, α-GaOOH with several novel microstructures has been synthesized at a low temperature and its subsequent thermal transformation. The influence of pH on the synthesis of α-GaOOH is studied, and the results indicate that pH played an important role in the microstructures of α-GaOOH and β-Ga 2 O 3 . All Ga 2 O 3 samples possess macro-mesoporous network structures and exhibits a remarkable photocatalytic activity for antibiotic degradation. The photoelectron chemical tests show that the separation efficiency of photogenerated charge carriers of Ga 2 O 3 -7.0 is higher than that of other Ga 2 O 3 . The enhanced photocatalytic activity of Ga 2 O 3 -7.0 is mainly ascribed to its morphology and oxygen vacancy. The active species trapping and photoluminescence measurement experiments indicate that OH and O 2 - are the major active species contributing to the photocatalytic process. This study will bring about the potential application in treatment of the antibiotic pollutants. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. 11. Photocopy of photograph (from St. Paul's Church) Photographer unknown ...

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

    11. Photocopy of photograph (from St. Paul's Church) Photographer unknown 1886 'EPISCOPAL CHURCH, CORNER OF 1ST AND J ST. BENICIA' WEST AND SOUTH SIDES - St. Paul's Episcopal Church, 120 East J Street, Benicia, Solano County, CA

  3. In situ dynamic observations of perovskite crystallisation and microstructure evolution intermediated from [PbI6]4- cage nanoparticles

    NASA Astrophysics Data System (ADS)

    Hu, Qin; Zhao, Lichen; Wu, Jiang; Gao, Ke; Luo, Deying; Jiang, Yufeng; Zhang, Ziyi; Zhu, Chenhui; Schaible, Eric; Hexemer, Alexander; Wang, Cheng; Liu, Yi; Zhang, Wei; Grätzel, Michael; Liu, Feng; Russell, Thomas P.; Zhu, Rui; Gong, Qihuang

    2017-06-01

    Hybrid lead halide perovskites have emerged as high-performance photovoltaic materials with their extraordinary optoelectronic properties. In particular, the remarkable device efficiency is strongly influenced by the perovskite crystallinity and the film morphology. Here, we investigate the perovskites crystallisation kinetics and growth mechanism in real time from liquid precursor continually to the final uniform film. We utilize some advanced in situ characterisation techniques including synchrotron-based grazing incident X-ray diffraction to observe crystal structure and chemical transition of perovskites. The nano-assemble model from perovskite intermediated [PbI6]4- cage nanoparticles to bulk polycrystals is proposed to understand perovskites formation at a molecular- or nano-level. A crystallisation-depletion mechanism is developed to elucidate the periodic crystallisation and the kinetically trapped morphology at a mesoscopic level. Based on these in situ dynamics studies, the whole process of the perovskites formation and transformation from the molecular to the microstructure over relevant temperature and time scales is successfully demonstrated.

  4. Mechanically durable superoleophobic aluminum surfaces with microstep and nanoreticula hierarchical structure for self-cleaning and anti-smudge properties.

    PubMed

    Peng, Shan; Bhushan, Bharat

    2016-01-01

    Superoleophobic aluminum surfaces are of interest for self-cleaning, anti-smudge (fingerprint resistance), anti-fouling, and corrosion resistance applications. In the published literature on superoleophobic aluminum surfaces, mechanical durability, self-cleaning, and anti-smudge properties data are lacking. Microstep structure has often been used to prepare superhydrophobic aluminum surfaces which produce the microstructure. The nanoreticula structure has also been used, and is reported to be able to trap air-pockets, which are desirable for a high contact angle. In this work, the microstep and nanoreticula structures were produced on aluminum surfaces to form a hierarchical micro/nanostructure by a simple two-step chemical etching process. The hierarchical structure, when modified with fluorosilane, made the surface superoleophobic. The effect of nanostructure, microstructure, and hierarchical structure on wettability and durability were studied and compared. The superoleophobic aluminum surfaces were found to be wear resistant, self-cleaning, and have anti-smudge and corrosion resistance properties. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. In situ dynamic observations of perovskite crystallisation and microstructure evolution intermediated from [PbI6]4− cage nanoparticles

    PubMed Central

    Hu, Qin; Zhao, Lichen; Wu, Jiang; Gao, Ke; Luo, Deying; Jiang, Yufeng; Zhang, Ziyi; Zhu, Chenhui; Schaible, Eric; Hexemer, Alexander; Wang, Cheng; Liu, Yi; Zhang, Wei; Grätzel, Michael; Liu, Feng; Russell, Thomas P.; Zhu, Rui; Gong, Qihuang

    2017-01-01

    Hybrid lead halide perovskites have emerged as high-performance photovoltaic materials with their extraordinary optoelectronic properties. In particular, the remarkable device efficiency is strongly influenced by the perovskite crystallinity and the film morphology. Here, we investigate the perovskites crystallisation kinetics and growth mechanism in real time from liquid precursor continually to the final uniform film. We utilize some advanced in situ characterisation techniques including synchrotron-based grazing incident X-ray diffraction to observe crystal structure and chemical transition of perovskites. The nano-assemble model from perovskite intermediated [PbI6]4− cage nanoparticles to bulk polycrystals is proposed to understand perovskites formation at a molecular- or nano-level. A crystallisation-depletion mechanism is developed to elucidate the periodic crystallisation and the kinetically trapped morphology at a mesoscopic level. Based on these in situ dynamics studies, the whole process of the perovskites formation and transformation from the molecular to the microstructure over relevant temperature and time scales is successfully demonstrated. PMID:28635947

  6. Effect of gelatinized flour fraction on thermal and rheological properties of wheat-based dough and bread.

    PubMed

    Carrillo-Navas, H; Guadarrama-Lezama, A Y; Vernon-Carter, E J; García-Díaz, S; Reyes, I; Alvarez-Ramírez, J

    2016-11-01

    This work considered gelatinized wheat flour fraction with properties similar to hydrocolloid to enhance the strength of dough network by improving water retention and rheological characteristics. The gelatinized (90 °C) fraction of the wheat flour was incorporated in the dough formulation at different levels (5, 10, and 20% w/w). The effects of the gelatinized flour (GF) fraction on the dough rheology and thermal properties were studied. The incorporation of GF induced a moderate increase of dough viscoelasticity and reduced the freezing and melting enthalpies. On the other hand, the changes in bread textural properties brought by incorporation of GF were insignificant, indicating that the gelatinized fraction acted as a binder that enhanced water trapping in the structure. SEM images showed a more heterogeneous crumb microstructure (e.g., gas cells, porous, etc.) bread prepared using GF. Drying kinetics obtained from TGA indicated that the water diffusivity decreased with the incorporation of GF, which suggested that the bread had a compact microstructure.

  7. A Perspective on Research Challenges in Information Security

    DTIC Science & Technology

    2011-11-01

    UNCLASSIFIED A Perspective on Research Challenges in Information Security Tamas Abraham, David Adie, Angela Billard, Paul Buckland, Michael Frangos ...Abstract (U) 4. AUTHORS Tamas Abraham, David Adie, Angela Billard, Paul Buckland, Michael Frangos , Ben Long, Mar- tin Lucas, Paul Montague, Dean Philp

  8. Proceedings of the 2009 Antenna Applications Symposium held in Monticello, Illinois on 22-24 September 2009. Volume 1

    DTIC Science & Technology

    2009-12-12

    Circuit Design, Theory and Applications. Prentice-Hall, 1 ed., 2000. 39 MEASUREMENT OF ELECTRICALLY SMALL ANTENNAS Suhail Barot, Paul E. Mayes, Paul ...2] “Ansoft HFSS, Version 9.2.1,” Ansoft Corporation, Pittsburgh, PA. 50 REDUCED-SIZE LINEAR ANTENNA ELEMENTS Paul E. Mayes, Paul W. Klock and...structures," IRE Internation convention, vol. 5, pp. 119-129, Mar 1957. [2] K. M. P. Aghdam, R. Faraji- Dana , and J. Rashed-Mohassel, "Compact dual

  9. The Influence of Microstructure on Deuterium Retention in Polycrystalline Tungsten

    DOE PAGES

    Garrison, Lauren M.; Meyer, Fred W.; Bannister, Mark E.

    2017-09-18

    The retention of hydrogen isotopes in the plasma-facing materials of a fusion reactor is dependent on the density of trapping sites in the material. One factor that can influence the trapping defects is the surface state of the material before exposure. Mechanically polished, electropolished, and recrystallized tungsten samples were compared by exposing them to 350 eV D + beams with peak fluences of ~1 × 10 24 D +/m 2 at 500 and 740 K at the Multicharged Ion Research Facility (MIRF). At the exposure temperature of 740 K, no significant retention was detected. For material exposed at 500 K,more » significant differences in retention were observed, and the order of increasing retention was recrystallized, electropolished, and mechanically polished. Lastly, the other variable besides surface treatment was the time delay between ion exposure and thermal desorption spectroscopy which also may have impacted the retention measurements if there was out-gassing of the D while samples were in storage before thermal desorption spectroscopy (TDS).« less

  10. The Influence of Microstructure on Deuterium Retention in Polycrystalline Tungsten

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garrison, Lauren M.; Meyer, Fred W.; Bannister, Mark E.

    The retention of hydrogen isotopes in the plasma-facing materials of a fusion reactor is dependent on the density of trapping sites in the material. One factor that can influence the trapping defects is the surface state of the material before exposure. Mechanically polished, electropolished, and recrystallized tungsten samples were compared by exposing them to 350 eV D + beams with peak fluences of ~1 × 10 24 D +/m 2 at 500 and 740 K at the Multicharged Ion Research Facility (MIRF). At the exposure temperature of 740 K, no significant retention was detected. For material exposed at 500 K,more » significant differences in retention were observed, and the order of increasing retention was recrystallized, electropolished, and mechanically polished. Lastly, the other variable besides surface treatment was the time delay between ion exposure and thermal desorption spectroscopy which also may have impacted the retention measurements if there was out-gassing of the D while samples were in storage before thermal desorption spectroscopy (TDS).« less

  11. Investigation of 'surface donors' in Al2O3/AlGaN/GaN metal-oxide-semiconductor heterostructures: Correlation of electrical, structural, and chemical properties

    NASA Astrophysics Data System (ADS)

    Ťapajna, M.; Stoklas, R.; Gregušová, D.; Gucmann, F.; Hušeková, K.; Haščík, Š.; Fröhlich, K.; Tóth, L.; Pécz, B.; Brunner, F.; Kuzmík, J.

    2017-12-01

    III-N surface polarization compensating charge referred here to as 'surface donors' (SD) was analyzed in Al2O3/AlGaN/GaN metal-oxide-semiconductor (MOS) heterojunctions using scaled oxide films grown by metal-organic chemical vapor deposition at 600 °C. We systematically investigated impact of HCl pre-treatment prior to oxide deposition and post-deposition annealing (PDA) at 700 °C. SD density was reduced down to 1.9 × 1013 cm-2 by skipping HCl pre-treatment step as compared to 3.3 × 1013 cm-2 for structures with HCl pre-treatment followed by PDA. The nature and origin of SD was then analyzed based on the correlation between electrical, micro-structural, and chemical properties of the Al2O3/GaN interfaces with different SD density (NSD). From the comparison between distributions of interface traps of MOS heterojunction with different NSD, it is demonstrated that SD cannot be attributed to interface trapped charge. Instead, variation in the integrity of the GaOx interlayer confirmed by X-ray photoelectron spectroscopy is well correlated with NSD, indicating SD may be formed by border traps at the Al2O3/GaOx interface.

  12. [Fatal diseases and "imaginary" suffering. "Hypochondria" and "consumption" in the correspondence between Jean Paul and Johann Bernhard Hermann, with a perspective on Jean Paul's literature and aesthetics].

    PubMed

    Meier, Monika

    2007-01-01

    The German writerJean Paul (Johann Paul Friedrich Richter, 1763-1825) and his friendJohann Bernhard Hermann (1761-1790) became acquainted with the thoughts of late Enlightenment at the University of Leipzig. They particularly appreciated the anthropology of Ernst Platner, who taught philosophy and aesthetics as well as medicine. Their confidential correspondence contains reflections on their respective situation and well being. Both write about feeling ill and label their illness "hypochondria". In the course of the correspondence Jean Paul's understanding of hypochondria evolves from an illness of the entrails as he follows Hermann, who supports the modern concept of hypochondria as an illness of the nerves. Two important themes from this correspondence recur in Jean Paul's novels and tales: firstly, his way of expressing comfort is related to his aesthetics, and secondly, the satirical way of portraying at least certain aspects of illness as imaginary reappears in his first successful novel "The Invisible Lodge" (1793).

  13. Effects of sintering temperature on the microstructural evolution and wear behavior of WCp reinforced Ni-based coatings

    NASA Astrophysics Data System (ADS)

    Chen, Chuan-hui; Bai, Yang; Ye, Xu-chu

    2014-12-01

    This article focuses on the microstructural evolution and wear behavior of 50wt%WC reinforced Ni-based composites prepared onto 304 stainless steel substrates by vacuum sintering at different sintering temperatures. The microstructure and chemical composition of the coatings were investigated by X-ray diffraction (XRD), differential thermal analysis (DTA), scanning and transmission electron microscopy (SEM and TEM) equipped with energy-dispersive X-ray spectroscopy (EDS). The wear resistance of the coatings was tested by thrust washer testing. The mechanisms of the decomposition, dissolution, and precipitation of primary carbides, and their influences on the wear resistance have been discussed. The results indicate that the coating sintered at 1175°C is composed of fine WC particles, coarse M6C (M=Ni, Fe, Co, etc.) carbides, and discrete borides dispersed in solid solution. Upon increasing the sintering temperature to 1225°C, the microstructure reveals few incompletely dissolved WC particles trapped in larger M6C, Cr-rich lamellar M23C6, and M3C2 in the austenite matrix. M23C6 and M3C2 precipitates are formed in both the γ/M6C grain boundary and the matrix. These large-sized and lamellar brittle phases tend to weaken the wear resistance of the composite coatings. The wear behavior is controlled simultaneously by both abrasive wear and adhesive wear. Among them, abrasive wear plays a major role in the wear process of the coating sintered at 1175°C, while the effect of adhesive wear is predominant in the coating sintered at 1225°C.

  14. Environmental fatigue of an Al-Li-Cu alloy. Part 2: Microscopic hydrogen cracking processes

    NASA Technical Reports Server (NTRS)

    Piascik, Robert S.; Gangloff, Richard P.

    1992-01-01

    Based on a fractographic analysis of fatigue crack propagation (FCP) in Al-Li-Cu alloy 2090 stressed in a variety of inert and embrittling environments, microscopic crack paths are identified and correlated with intrinsic da/dN-delta K kinetics. FCP rates in 2090 are accelerated by hydrogen producing environments (pure water vapor, moist air, and aqueous NaCl), as defined in Part 1. For these cases, subgrain boundary fatigue cracking (SGC) dominates for delta K values where the crack tip process zone, a significant fraction of the cyclic plastic zone, is sufficiently large to envelop 5 micron subgrains in the unrecrystallized microstructure. SGC may be due to strong hydrogen trapping at T1 precipitates concentrated at sub-boundaries. At low delta K, the plastic zone diameter is smaller than the subgrain size and FCP progresses along (100) planes due to either local lattice decohesion or aluminum-lithium hydride cracking. For inert environments (vacuum, helium, and oxygen), or at high delta K where the hydrogen effect on da/dN is small, FCP is along (111) slip planes; this mode does not transition with increasing delta K and plastic zone size. The SGC and (100) crystallographic cracking modes, and the governing influence of the crack tip process zone volume (delta K), support hydrogen embrittlement rather than a surface film rupture and anodic dissolution mechanism for environmental FCP. Multi-sloped log da/dN-log delta K behavior is produced by changes in process zone hydrogen-microstructure interactions, and not by purely micromechanical-microstructure interactions, in contradiction to microstructural distance-based fatigue models.

  15. A cross-cultural comparison of eating behaviors and home food environmental factors in adolescents from São Paulo (Brazil) and Saint Paul/Minneapolis (USA)

    PubMed Central

    Estima, Camilla C.P.; Bruening, Meg; Hannan, Peter J.; Alvarenga, Marle S.; Leal, Greisse V.S.; Philippi, Sonia T.; Neumark-Sztainer, Dianne

    2015-01-01

    Objective Describe cross-cultural differences in nutrition-related factors among adolescents from São Paulo, Brazil and St. Paul/Minneapolis, U.S. Design Two large- population-based studies with cross-cultural comparisons Setting 12 São Paulo and 10 St. Paul/Minneapolis high schools in 2009-2010 Participants 1148 adolescents from São Paulo; 1632 adolescents from St. Paul/Minneapolis Main outcome measure(s) Meal consumption, family meals, fast food consumption and home food availability Analysis Binomial regressions, weighted for age distributions and adjusted for gender, were used to compare identical measures from each sample. Results Generally, São Paulo adolescents reported healthier nutritional outcomes than St. Paul/Minneapolis adolescents. São Paulo adolescents were seven times less likely to report high fast food consumption than St. Paul/Minneapolis adolescents (p<0.001). While most measures of the home environment indicated healthier home environments in São Paulo, more São Paulo adolescents reported that sugar-sweetened beverages was usually available at home than St. Paul/Minneapolis adolescents (p<0.001). Conclusions and implications São Paulo youth tended to have healthier eating behaviors and home food environment factors than St. Paul/Minneapolis youth. Brazilian eating patterns tend to be healthier and support a connection with food and culture. Interventions are needed to encourage youth and their families to maintain these patterns. PMID:24656651

  16. A cross-cultural comparison of eating behaviors and home food environmental factors in adolescents from São Paulo (Brazil) and Saint Paul-Minneapolis (US).

    PubMed

    Estima, Camilla C P; Bruening, Meg; Hannan, Peter J; Alvarenga, Marle S; Leal, Greisse V S; Philippi, Sonia T; Neumark-Sztainer, Dianne

    2014-01-01

    Describe cross-cultural differences in nutrition-related factors among adolescents from São Paulo, Brazil and St Paul-Minneapolis, US. Two large-population-based studies with cross-cultural comparisons. Twelve São Paulo and 10 St Paul-Minneapolis high schools in 2009-2010. A total of 1,148 adolescents from São Paulo and 1,632 adolescents from St Paul-Minneapolis. Meal consumption, family meals, fast-food consumption, and home food availability. Binomial regressions, weighted for age distributions and adjusted for gender, were used to compare identical measures from each sample. Generally, São Paulo adolescents reported healthier nutritional outcomes than St Paul-Minneapolis adolescents. São Paulo adolescents were 7 times less likely to report high fast-food consumption than St Paul-Minneapolis adolescents (P < .001). Whereas most measures of the home environment indicated healthier home environments in São Paulo, more São Paulo adolescents reported that sugar-sweetened beverages were usually available at home than did St Paul-Minneapolis adolescents (P < .001). São Paulo youth tended to have healthier eating behaviors and home food environment factors than St Paul-Minneapolis youth. Brazilian eating patterns tend to be healthier and support a connection with food and culture. Interventions are needed to encourage youth and their families to maintain these patterns. Copyright © 2014 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  17. [From Paul Flechsig to the Paul Flechsig Institute for Brain Research. Development of brain research at the Karl Marx University].

    PubMed

    Leibnitz, L; Werner, L; Schober, W; Brauer, K

    1977-04-01

    A review is given on the development of the brain research institute of the Karl-Marx-University of Leipzig during the directorates of Paul Flechsig (1883-1920), Richard Arwed Pfeifer (1925-1957), and Wolfgang Wünscher (1957-1971).

  18. 67. Photocopy of photograph (original print in the Minnesota Historical ...

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

    67. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul Minnesota, ca. 1925. #35109. Photographer: St. Paul Daily News.) VIEW TO NORTHEAST, SHOWING SPAN NOS. 9-19, ca. 1925 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  19. 63. Photocopy of photograph (original print in the Minnesota Historical ...

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

    63. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1958. #31008. Photographer: St. Paul Dispatch-Pioneer Press.) AERIAL VIEW OF HIGH BRIDGE, LOOKING SOUTHWEST, 1958 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  20. 68. Photocopy of photograph (original print in the Minnesota Historical ...

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

    68. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1924. #35108. Photographer: St. Paul Daily News.) VIEW TO EAST, SHOWING SPAN NOS. 10-20, 1924 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  1. Catalytic Creativity: The Case of Linus Pauling.

    ERIC Educational Resources Information Center

    Nakamura, Jeanne; Csikszentmihalyi, Mihaly

    2001-01-01

    Illustrates how creativity is constituted by forces beyond the innovating individual, drawing examples from the career of chemist Linus Pauling that highlight the formative influence of the social field on an individual's relationship to the domain. Pauling's case reveals how variously the social field contributes to creativity, shaping the…

  2. Debating Paul

    ERIC Educational Resources Information Center

    Torbett, David

    2007-01-01

    This classroom note describes the lessons I learned from the use of formal debates during the two semesters I taught "Paul and Early Christianity" to undergraduates at a liberal arts college in Ohio. The purpose of the course was primarily to give students the exegetical skills to understand Paul in his own context. The secondary purpose…

  3. 78 FR 76143 - Proposed CERCLA Settlement Relating to the Paul's Tank Cleaning Service Superfund Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-16

    ... Paul's Tank Cleaning Service Superfund Site, Burlington County, New Jersey AGENCY: Environmental.... (``Settling Party''). The Settling Party is a potentially responsible party, pursuant to Section 107(a) of CERCLA, and thus is potentially liable for response costs incurred at or in connection Paul's Tank...

  4. The great man from Tarsus: Freud on the apostle Paul.

    PubMed

    Westerink, Herman

    2007-01-01

    The author describes developments in Freud's writings concerning his views on the apostle Paul. This development shows that Freud more and more clearly regarded Paul as a key figure in understanding the complex relationship between Judaism and Christianity--and also as a man who essentially has no comfortable place in either of these religions. For Freud, Paul was a unique figure, an analyst of the human character and of his own culture and religion--a Jew who tried to free himself and his people from the burden of the sense of guilt.

  5. 31. Photocopy of line illustration; originally published in William N. ...

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

    31. Photocopy of line illustration; originally published in William N. Carey, 'St. Paul Builds an Airport One Mile From Post Office,' Engineering News-Record, (August 21, 1930), figure 6, page 294; SHOWS CANTILEVERED ROOF-TRUSS SYSTEM OF MUNICIPAL HANGAR COMPLETED AT ST. PAUL MUNICIPAL AIRPORT IN 1930; THE STRUCTURAL DESIGN WAS BASED ON THAT OF THE NORTHWEST AIRWAYS HANGAR, EXCEPT FOR THE SUBSTITUTION OF BOWSTRING TRUSSES FOR TRAPEZOIDAL TRUSSES - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  6. Multistep estimators of the between-study variance: The relationship with the Paule-Mandel estimator.

    PubMed

    van Aert, Robbie C M; Jackson, Dan

    2018-04-26

    A wide variety of estimators of the between-study variance are available in random-effects meta-analysis. Many, but not all, of these estimators are based on the method of moments. The DerSimonian-Laird estimator is widely used in applications, but the Paule-Mandel estimator is an alternative that is now recommended. Recently, DerSimonian and Kacker have developed two-step moment-based estimators of the between-study variance. We extend these two-step estimators so that multiple (more than two) steps are used. We establish the surprising result that the multistep estimator tends towards the Paule-Mandel estimator as the number of steps becomes large. Hence, the iterative scheme underlying our new multistep estimator provides a hitherto unknown relationship between two-step estimators and Paule-Mandel estimator. Our analysis suggests that two-step estimators are not necessarily distinct estimators in their own right; instead, they are quantities that are closely related to the usual iterative scheme that is used to calculate the Paule-Mandel estimate. The relationship that we establish between the multistep and Paule-Mandel estimator is another justification for the use of the latter estimator. Two-step and multistep estimators are perhaps best conceptualized as approximate Paule-Mandel estimators. © 2018 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

  7. Paul's gospel and the rhetoric of apostolic rejection: A study of Galatians 1:15--17, 1 Corinthians 15:8, F. C. Baur, and the origins of Paul's Gentile mission

    NASA Astrophysics Data System (ADS)

    Mitchell, Matthew Wesley

    This dissertation proposes a new understanding of Paul's Gentile mission and its relationship to his so-called "conversion." This dissertation examines the origins of Paul's mission to the Gentiles, and locates it in his claims to have been personally commissioned to undertake such a mission by Jesus. Specifically, I argue that it is the rejection of Paul's claim to be an apostle, a claim founded upon his "conversion" experience, that precipitates his mission to the Gentiles. In arguing this view, I draw upon Ferdinand Christian Baur's nineteenth century theories concerning both the unreliability of Acts as a historical source, and his proposal of a clear division between Paul and the other apostles. In establishing the methodological and theoretical framework of the dissertation, I discuss the "New Perspective on Paul" that has dominated New Testament scholarship over the past thirty years. My study is also informed methodologically by the growing interest in rhetorical criticism among biblical scholars, although the emphasis of this dissertation bears more of a resemblance to the approach of the New Rhetoric than the categories of classical, Greco-Roman rhetoric. The textual component of this work falls into two stages. The first contains a full examination of Paul's "conversion passages" in Galatians 1:15--17 and 1 Corinthians 15:8, attempting to situate these seemingly unusual self-descriptions in their cultural contexts. The second involves an examination of F. C. Baur's presentation of Paul, and the reception of Baur's views among biblical scholars throughout the years following his scholarly activity. This dissertation makes two claims, each of which can stand on its own as an important contribution to scholarship. My first claim is that components of Baur's work support my proposal concerning Paul's Gentile mission and his experience of apostolic rejection, and that this proposal has much to commend it as an explanation of a perennial scholarly puzzle. My second claim is methodological, as I demonstrate that scholarly writings about Paul and his modern interpreters are themselves exercises in argumentation, and thus are not to be accepted uncritically, or without close attention to the rhetorical practices they utilize.

  8. 72. Photocopy of photograph (original print in the Minnesota Historical ...

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

    72. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, June 25, 1958. #31024. Photographer: St. Paul Dispatch-Pioneer Press. VIEW TO SOUTH, SHOWING THE RESURFACING OF THE BRIDGE IN 1958 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  9. 64. Photocopy of photograph (original print in the Minnesota Historical ...

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

    64. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul Minnesota, ca. 1891. #35805. Photographer: Haynes and Bros., St. Paul.) VIEW TO SOUTH, SHOWING FOUR PERCENT GRADE OF HIGH BRIDGE, ca. 1981 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  10. 76 FR 18725 - Marine Mammals; File Nos. 14330 and 14335

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ... (Phoca vitulina) on St. Paul, St. George, Otter, and Walrus Islands, and Sea Lion Rock, all of the... marine mammals in Alaska: (File No. 14330) the Aleut Community of St. Paul Island, Tribal Government, Ecosystem Conservation Office, St. Paul Island, AK; and (File No. 14335) the Alaska SeaLife Center, Seward...

  11. In Conversation with Paul Richards

    ERIC Educational Resources Information Center

    Holman, Andrew

    2013-01-01

    Paul Richards is one of those individuals who make a difference and is as far from institutional as one can be. The author met up with him at the Learning Disability Today conference in London to talk more about his work and life. Paul coordinates the service user involvement across Southdown Housing Association, based in Sussex.

  12. 76 FR 9278 - Safety Zone; Fourth Annual Offshore Challenge, Sunny Isles Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-17

    ... Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A.Steiner@uscg.mil . If you have questions on viewing or submitting material to the docket, call.... Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535- 8724, e-mail Paul.A.Steiner...

  13. 75 FR 77899 - Notice of Inventory Completion: Minnesota Indian Affairs Council, St. Paul and Bemidji, MN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... DEPARTMENT OF THE INTERIOR National Park Service [2253-665] Notice of Inventory Completion: Minnesota Indian Affairs Council, St. Paul and Bemidji, MN AGENCY: National Park Service, Interior. ACTION... funerary objects in the possession of the Minnesota Indian Affairs Council, St. Paul and Bemidji, MN. The...

  14. Paul Torcellini | NREL

    Science.gov Websites

    | 303-384-7528 Paul is the principal engineer for the Commercial Buildings Research Group and has been at the NREL for 19 years. Prior to this role, he was the group manager for the Commercial Buildings articles related to energy efficiency and zero-energy commercial buildings. Among his many awards, Paul has

  15. 75 FR 34670 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; Revision to Emission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ... Promulgation of Air Quality Implementation Plans; Maryland; Revision to Emission Limitations for R. Paul Smith... revision pertains to revised emission limitations for the R. Paul Smith Power Station located in Washington... R. Paul Smith Power Station in Washington County. This facility had annual nitrogen oxides (NOx...

  16. Paul Voosen Receives 2013 David Perlman Award for Excellence in Science Journalism—News: Citation

    NASA Astrophysics Data System (ADS)

    Zaneski, Cyril T.

    2014-01-01

    It's my pleasure to nominate Paul Voosen, the former science reporter for Greenwire, for the David Perlman award. Last November, as Superstorm Sandy pounded the East Coast of the United States, Paul found himself stranded for several days in Miami, mourning a recently deceased family member.

  17. 78 FR 59317 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; Revision to Emission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-26

    ... for R. Paul Smith Power Station; Withdrawal of Proposed Rule AGENCY: Environmental Protection Agency... revision pertains to revised emission limitations for the R. Paul Smith Power Station located in Washington... action to approve the revised emission limitations for the R. Paul Smith Power Station contained in the...

  18. The Incalculable Benefits of Revitalizing Your Board

    ERIC Educational Resources Information Center

    Holtschneider, Dennis H.

    2013-01-01

    DePaul University has grown in size and stature in the last decade. Chicago's "little school under the El," as DePaul was once known, is now the nation's largest Catholic university and the largest private, nonprofit university in the Midwest. DePaul University restructured its board, enabling it to play an important role in the…

  19. 78 FR 29612 - Prevailing Rate Systems; Redefinition of the Minneapolis-St. Paul, MN, and Southwestern Wisconsin...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-21

    ... OFFICE OF PERSONNEL MANAGEMENT 5 CFR Part 532 RIN 3206-AM75 Prevailing Rate Systems; Redefinition of the Minneapolis-St. Paul, MN, and Southwestern Wisconsin Appropriated Fund Federal Wage System.... Paul, MN, and Southwestern Wisconsin appropriated fund Federal Wage System (FWS) wage areas. The final...

  20. Partnering for Environmental Security Cooperation in Central Asia and the Caspian Basin

    DTIC Science & Technology

    2002-04-01

    Organizations.......................................................................................98 Mr. Paul Giannone Disaster Response Planning Processes...Paul Giannone of CARE USA who discussed key points of Non-governmental Organizations’ relationships with the military and provided suggestions on...Relationships between Military and Civilian Organizations Mr. Paul Giannone Disaster Response Planning Processes and Procedures Mr. Wolfgang G

  1. Effect of starting microstructure on helium plasma-materials interaction in tungsten

    DOE PAGES

    Wang, Kun; Bannister, Mark E.; Meyer, Fred W.; ...

    2016-11-24

    Here, in a magnetic fusion energy (MFE) device, the plasma-facing materials (PFMs) will be subjected to tremendous fluxes of ions, heat, and neutrons. The response of PFMs to the fusion environment is still not well defined. Tungsten metal is the present candidate of choice for PFM applications such as the divertor in ITER. However, tungsten's microstructure will evolve in service, possibly to include recrystallization. How tungsten's response to plasma exposure evolves with changes in microstructure is presently unknown. In this work, we have exposed hot-worked and recrystallized tungsten to an 80 eV helium ion beam at a temperature of 900more » °C to fluences of 2 × 10 23 or 20 × 10 23 He/m 2. This resulted in a faceted surface structure at the lower fluence or short but well-developed nanofuzz structure at the higher fluence. There was little difference in the hot-rolled or recrystallized material's near-surface (≤50 nm) bubbles at either fluence. At higher fluence and deeper depth, the bubble populations of the hot-rolled and recrystallized were different, the recrystallized being larger and deeper. This may explain previous high-fluence results showing pronounced differences in recrystallized material. The deeper penetration in recrystallized material also implies that grain boundaries are traps, rather than high-diffusivity paths.« less

  2. Characterization of Cerebral White Matter Properties Using Quantitative Magnetic Resonance Imaging Stains

    PubMed Central

    Hurley, Samuel A.; Samsonov, Alexey A.; Adluru, Nagesh; Hosseinbor, Ameer Pasha; Mossahebi, Pouria; Tromp, Do P.M.; Zakszewski, Elizabeth; Field, Aaron S.

    2011-01-01

    Abstract The image contrast in magnetic resonance imaging (MRI) is highly sensitive to several mechanisms that are modulated by the properties of the tissue environment. The degree and type of contrast weighting may be viewed as image filters that accentuate specific tissue properties. Maps of quantitative measures of these mechanisms, akin to microstructural/environmental-specific tissue stains, may be generated to characterize the MRI and physiological properties of biological tissues. In this article, three quantitative MRI (qMRI) methods for characterizing white matter (WM) microstructural properties are reviewed. All of these measures measure complementary aspects of how water interacts with the tissue environment. Diffusion MRI, including diffusion tensor imaging, characterizes the diffusion of water in the tissues and is sensitive to the microstructural density, spacing, and orientational organization of tissue membranes, including myelin. Magnetization transfer imaging characterizes the amount and degree of magnetization exchange between free water and macromolecules like proteins found in the myelin bilayers. Relaxometry measures the MRI relaxation constants T1 and T2, which in WM have a component associated with the water trapped in the myelin bilayers. The conduction of signals between distant brain regions occurs primarily through myelinated WM tracts; thus, these methods are potential indicators of pathology and structural connectivity in the brain. This article provides an overview of the qMRI stain mechanisms, acquisition and analysis strategies, and applications for these qMRI stains. PMID:22432902

  3. Theoretical limits of the multistacked 1D and 2D microstructured inorganic solar cells

    NASA Astrophysics Data System (ADS)

    Yengel, Emre; Karaagac, Hakan; VJ, Logeeswaran; Islam, M. Saif

    2015-09-01

    Recent studies in monocrystalline semiconductor solar cells are focused on mechanically stacking multiple cells from different materials to increase the power conversion efficiency. Although, the results show promising increase in the device performance, the cost remains as the main drawback. In this study, we calculated the theoretical limits of multistacked 1D and 2D microstructered inorganic monocrstalline solar cells. This system is studied for Si and Ge material pair. The results show promising improvements in the surface reflection due to enhanced light trapping caused by photon-microstructures interactions. The theoretical results are also supported with surface reflection and angular dependent power conversion efficiency measurements of 2D axial microwall solar cells. We address the challenge of cost reduction by proposing to use our recently reported mass-manufacturable fracture-transfer- printing method which enables the use of a monocrystalline substrate wafer for repeated fabrication of devices by consuming only few microns of materials in each layer of devices. We calculated thickness dependent power conversion efficiencies of multistacked Si/Ge microstructured solar cells and found the power conversion efficiency to saturate at 26% with a combined device thickness of 30 μm. Besides having benefits of fabricating low-cost, light weight, flexible, semi-transparent, and highly efficient devices, the proposed fabrication method is applicable for other III-V materials and compounds to further increase the power conversion efficiency above 35% range.

  4. Nonlinear Ion Harmonics in the Paul Trap with Added Octopole Field: Theoretical Characterization and New Insight into Nonlinear Resonance Effect.

    PubMed

    Xiong, Caiqiao; Zhou, Xiaoyu; Zhang, Ning; Zhan, Lingpeng; Chen, Yongtai; Nie, Zongxiu

    2016-02-01

    The nonlinear harmonics within the ion motion are the fingerprint of the nonlinear fields. They are exclusively introduced by these nonlinear fields and are responsible to some specific nonlinear effects such as nonlinear resonance effect. In this article, the ion motion in the quadrupole field with a weak superimposed octopole component, described by the nonlinear Mathieu equation (NME), was studied by using the analytical harmonic balance (HB) method. Good accuracy of the HB method, which was comparable with that of the numerical fourth-order Runge-Kutta (4th RK), was achieved in the entire first stability region, except for the points at the stability boundary (i.e., β = 1) and at the nonlinear resonance condition (i.e., β = 0.5). Using the HB method, the nonlinear 3β harmonic series introduced by the octopole component and the resultant nonlinear resonance effect were characterized. At nonlinear resonance, obvious resonant peaks were observed in the nonlinear 3β series of ion motion, but were not found in the natural harmonics. In addition, both resonant excitation and absorption peaks could be observed, simultaneously. These are two unique features of the nonlinear resonance, distinguishing it from the normal resonance. Finally, an approximation equation was given to describe the corresponding working parameter, q nr , at nonlinear resonance. This equation can help avoid the sensitivity degradation due to the operation of ion traps at the nonlinear resonance condition.

  5. Precise measurement of the angular correlation parameter aβν in the β decay of 35Ar with LPCTrap

    NASA Astrophysics Data System (ADS)

    Fabian, X.; Ban, G.; Boussaïd, R.; Breitenfeldt, M.; Couratin, C.; Delahaye, P.; Durand, D.; Finlay, P.; Fléchard, X.; Guillon, B.; Lemière, Y.; Leredde, A.; Liénard, E.; Méry, A.; Naviliat-Cuncic, O.; Pierre, E.; Porobic, T.; Quéméner, G.; Rodríguez, D.; Severijns, N.; Thomas, J. C.; Van Gorp, S.

    2014-03-01

    Precise measurements in the β decay of the 35Ar nucleus enable to search for deviations from the Standard Model (SM) in the weak sector. These measurements enable either to check the CKM matrix unitarity or to constrain the existence of exotic currents rejected in the V-A theory of the SM. For this purpose, the β-ν angular correlation parameter, aβν, is inferred from a comparison between experimental and simulated recoil ion time-of-flight distributions following the quasi-pure Fermi transition of 35Ar1+ ions confined in the transparent Paul trap of the LPCTrap device at GANIL. During the last experiment, 1.5×106 good events have been collected, which corresponds to an expected precision of less than 0.5% on the aβν value. The required simulation is divided between the use of massive GPU parallelization and the GEANT4 toolkit for the source-cloud kinematics and the tracking of the decay products.

  6. Layer Splitting in a Complex Plasma

    NASA Astrophysics Data System (ADS)

    Smith, Bernard; Hyde, Truell; Matthews, Lorin; Johnson, Megan; Cook, Mike; Schmoke, Jimmy

    2009-11-01

    Dust particle clouds are found in most plasma processing environments and many astrophysical environments. Dust particles suspended within such plasmas often acquire an electric charge from collisions with free electrons in the plasma. Depending upon the ratio of interparticle potential energy to average kinetic energy, charged dust particles can form a gaseous, liquid or crystalline structure with short to longer range ordering. An interesting facet of complex plasma behavior is that particle layers appear to split as the DC bias is increased. This splitting of layers points to a phase transition differing from the normal phase transitions found in two-dimensional solids. In 1993, Dubin noted that as the charged particle density of an initially two-dimensional Coulomb crystal increases the system's layers split at specific charge densities. This work modeled ions in a Paul or Penning trap, but may be applicable to dusty plasma systems as well. This work will discuss this possibility along with splitting observed in the CASPER GEC rf Reference Cell at specific pressures and powers.

  7. Absolute Frequency Measurement of the {sup 40}Ca{sup +} 4s {sup 2}S{sub 1/2}-3d {sup 2}D{sub 5/2} Clock Transition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chwalla, M.; Kim, K.; Monz, T.

    2009-01-16

    We report on the first absolute transition frequency measurement at the 10{sup -15} level with a single, laser-cooled {sup 40}Ca{sup +} ion in a linear Paul trap. For this measurement, a frequency comb is referenced to the transportable Cs atomic fountain clock of LNE-SYRTE and is used to measure the {sup 40}Ca{sup +} 4s {sup 2}S{sub 1/2}-3d {sup 2}D{sub 5/2} electric-quadrupole transition frequency. After the correction of systematic shifts, the clock transition frequency {nu}{sub Ca{sup +}}=411 042 129 776 393.2(1.0) Hz is obtained, which corresponds to a fractional uncertainty within a factor of 3 of the Cs standard. In addition,more » we determine the Landeg factor of the 3d{sup 2}D{sub 5/2} level to be g{sub 5/2}=1.200 334 0(3)« less

  8. 75 FR 72964 - Determinations of Attainment by the Applicable Attainment Date for the Hayden, Nogales, Paul Spur...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-29

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [R09-OAR-2010-0718; FRL-9233-1] Determinations of Attainment by the Applicable Attainment Date for the Hayden, Nogales, Paul Spur/Douglas PM10 Nonattainment... November 2, 2010 (75 FR 67220), direct final rule determining that the Hayden, Nogales, and Paul Spur...

  9. 28. Photocopy of photograph dated ca. 1940; photographer unknown; original ...

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

    28. Photocopy of photograph dated ca. 1940; photographer unknown; original filed as MR2.9/SP8/r373 in Audio-Visual Collection of Minnesota Historical Society, St. Paul; WEST SIDE AFTER SECOND-STORY ADDITION; LOOKING EAST - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  10. Religion in the Locker Room

    ERIC Educational Resources Information Center

    Price, Sean

    2013-01-01

    In September 2011, Paul Phillips stepped out of his football team's field house and into a struggle over the separation of church and state. Like most teams, Paul's practiced after school. But one day he found that the coach had called in a local minister to conduct a weekly half-hour "team chapel" before practice. Paul, who does not believe in…

  11. 76 FR 24840 - Safety Zone; 2011 Rohto Ironman 70.3 Miami, Biscayne Bay, Miami, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ... Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A.Steiner@uscg.mil . If you have questions on viewing or submitting material to the docket, call... Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail...

  12. 76 FR 34649 - Foreign-Trade Zone 119-Minneapolis-St. Paul, MN; Application for Reorganization Under Alternative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ...--Minneapolis-St. Paul, MN; Application for Reorganization Under Alternative Site Framework An application has... current zone project includes the following sites: Site 1 (3,002 acres)--located at the Minneapolis-St...); Site 9 (20 acres)--1700 Wynne Avenue, St. Paul (Ramsey County); and, Site 10 (236 acres)-- Bloomington...

  13. Paul D. Boyer, Adenosine Triphosphate (ATP), and the Binding Change

    Science.gov Websites

    -- October 1975, DOE Technical Report, 1975 A Perspective of the Binding Change Mechanism for ATP Synthesis Reports, Vol. 18, No. 3, 1998 ATP Synthesis and the Binding Change Mechanism: The Work of Paul D. Boyer Mechanism of ATP Synthesis Additional Web Pages: Adenosine Triphosphate: The Energy Currency of Life Paul D

  14. 78 FR 28633 - Prometric, Inc., a Subsidiary of Educational Testing Service, Including On-Site Leased Workers...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-15

    ... Subsidiary of Educational Testing Service, Including On-Site Leased Workers From Office Team St. Paul... Office Team were employed on-site at the St. Paul, Minnesota location of the subject firm. The Department... workers leased from Office Team working on- site at the St. Paul, Minnesota location of Prometric, Inc., a...

  15. 26. Photocopy of photograph dated 1930; photographer unknown; original filed ...

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

    26. Photocopy of photograph dated 1930; photographer unknown; original filed as MR2.9/SP8/p343 in Audio-Visual Collection of Minnesota Historical Society, St. Paul; THREE-QUARTER VIEW SHOWING WEST SIDE AND SOUTH FRONT SHORTLY AFTER COMPLETION; LOOKING NORTHEAST - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  16. 27. Photocopy of photograph dated ca. 1940; photographer unknown; original ...

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

    27. Photocopy of photograph dated ca. 1940; photographer unknown; original filed as MR2.9/SP8/r374 in Audio-Visual Collection Minnesota Historical Society, St. Paul; THREE-QUARTER VIEW SHOWING WEST SIDE AND SOUTH FRONT AFTER SECOND-STORY ADDITION; LOOKING NORTHEAST - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  17. Ultrasonically Activated Diffusion Bonding for Fluidic Control Assembly

    DTIC Science & Technology

    1979-02-01

    CONTROL ASSEMBLY SONOBOND CORPORATION SUBSIDIARY OF CHRISTIAN METALS CORPORATION WEST CHESTER, PENNSYLVANIA HOWARD A. SCHEETZ PAUL L. COPPA JANET...FLUIDIC CONTROL ASSEMBLY Howard A. Scheetz Paul L. Coppa Janet Devine Sonobond Corporation Subsidiary of Christiana Metals Corporation West... Paul L. Coppa Janet Devine fl. CONTRACT OR GRANT NUMBERS.) Contract No. DAAA21-76-C-0136 ». PERFORMING ORGANIZATION N AM t AND ADDRESS

  18. Paul of Tarsus: The Ancient Model of "Parrhesia" or Freedom of Speech.

    ERIC Educational Resources Information Center

    Keefe, Carolyn

    The word "parrhesia" is of Greek origin and indicates the right to say anything a person chooses. The Apostle Paul was himself an operational definition of parrhesia, and a term that symbolizes such a controlling force on such a significant figure is worthy of examination and academic study. For Paul, his work as an evangelist and pastor was a…

  19. A simulation study for determination of refractive index dispersion of dielectric film from reflectance spectrum by using Paul wavelet

    NASA Astrophysics Data System (ADS)

    Tiryaki, Erhan; Coşkun, Emre; Kocahan, Özlem; Özder, Serhat

    2017-02-01

    In this work, the Continuous Wavelet Transform (CWT) with Paul wavelet was improved as a tool for determination of refractive index dispersion of dielectric film by using the reflectance spectrum of the film. The reflectance spectrum was generated theoretically in the range of 0.8333 - 3.3333 μm wavenumber and it was analyzed with presented method. Obtained refractive index determined from various resolution of Paul wavelet were compared with the input values, and the importance of the tunable resolution with Paul wavelet was discussed briefly. The noise immunity and uncertainty of the method was also studied.

  20. In situ dynamic observations of perovskite crystallisation and microstructure evolution intermediated from [PbI 6] 4– cage nanoparticles

    DOE PAGES

    Hu, Qin; Zhao, Lichen; Wu, Jiang; ...

    2017-06-21

    Hybrid lead halide perovskites have emerged as high-performance photovoltaic materials with their extraordinary optoelectronic properties. In particular, the remarkable device efficiency is strongly influenced by the perovskite crystallinity and the film morphology. Here, we investigate the perovskites crystallisation kinetics and growth mechanism in real time from liquid precursor continually to the final uniform film. We utilize some advanced in situ characterisation techniques including synchrotron-based grazing incident X-ray diffraction to observe crystal structure and chemical transition of perovskites. The nano-assemble model from perovskite intermediated [PbI 6] 4– cage nanoparticles to bulk polycrystals is proposed to understand perovskites formation at a molecular-more » or nano-level. A crystallisation-depletion mechanism is developed to elucidate the periodic crystallisation and the kinetically trapped morphology at a mesoscopic level. Based on these in situ dynamics studies, the whole process of the perovskites formation and transformation from the molecular to the microstructure over relevant temperature and time scales is successfully demonstrated.« less

  1. Theory of Semiconducting Superlattices and Microstructures

    DTIC Science & Technology

    1992-03-01

    A)dee on ZnSc layer thic~ness V (number of ZnSe molecules thick) It is Ga ashallowit h do o nu io and s e x de trap (mak.i for N X 10 ZnSe/ZnO,$MnO...ZnSe (which can be easily doped n-type r but not p-type) and ZnTe (which can be doped 15 p-type): de ~ep levels that lie in the gap of ZnSe and btrap...1101 SX. Ren. 3.D. Dow and S. Klemmn. J. Appl. Vh’.-s. in press,search. the Army Research Office, and the De . 111) 3.D. Dow. Run-Di Hong. S, Klemm

  2. Analysis of the threshold switching mechanism of a Te-SbO selector device for crosspoint nonvolatile memory applications

    NASA Astrophysics Data System (ADS)

    Kim, Young Seok; Park, Ji Woon; Lee, Jong Ho; Choi, In Ah; Heo, Jaeyeong; Kim, Hyeong Joon

    2017-10-01

    The threshold switching mechanism of Te-SbO thin films with a unique microstructure in which a Te nanocluster is present in the SbO matrix is analyzed. During the electro-forming process, amorphous Te filaments are formed in the Te nanocluster. However, unlike conventional Ovonic threshold switching (TS) selector devices, it has been demonstrated that the off-current flows along the filament. Numerical calculations show that the off-current is due to the trap present in the filament. We also observed changes in TS parameters through controls in the strength or volume of the filaments.

  3. A multi-technique analysis of deuterium trapping and near-surface precipitate growth in plasma-exposed tungsten

    DOE PAGES

    Kolasinski, Robert; Shimada, Masashi; Oya, Yasuhisa; ...

    2015-08-17

    We examine how deuterium becomes trapped in plasma-exposed tungsten and forms near-surface platelet-shaped precipitates. How these bubbles nucleate and grow, as well as the amount of deuterium trapped within, is crucial for interpreting the experimental database. Here, we use a combined experimental/theoretical approach to provide further insight into the underlying physics. With the Tritium Plasma Experiment, we exposed a series of ITER-gradetungsten samples to high flux D plasmas (up to 1.5 × 10 22 m -2 s -1) at temperatures ranging between 103 and 554 °C. Retention of deuterium trapped in the bulk, assessed through thermal desorption spectrometry, reached amore » maximum at 230 °C and diminished rapidly thereafter for T > 300 °C. Post-mortem examination of the surfaces revealed non-uniform growth of bubbles ranging in diameter between 1 and 10 μm over the surface with a clear correlation with grain boundaries. Electron back-scattering diffraction maps over a large area of the surface confirmed this dependence; grains containing bubbles were aligned with a preferred slip vector along the <111> directions. Focused ion beam profiles suggest that these bubbles nucleated as platelets at depths of 200 nm–1 μm beneath the surface and grew as a result of expansion of sub-surface cracks. Furthermore, to estimate the amount of deuterium trapped in these defects relative to other sites within the material, we applied a continuum-scale treatment of hydrogen isotope precipitation. Additionally, we propose a straightforward model of near-surface platelet expansion that reproduces bubble sizes consistent with our measurements. For the tungsten microstructure considered here, we find that bubbles would only weakly affect migration of D into the material, perhaps explaining why deep trapping was observed in prior studies with plasma-exposed neutron-irradiated specimens. We foresee no insurmountable issues that would prevent the theoretical framework developed here from being extended to a broader range of systems where precipitation of insoluble gases in ion beam or plasma-exposed metals is of interest.« less

  4. 29. Photocopy of photograph dated 1930; photographer unknown; original filed ...

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

    29. Photocopy of photograph dated 1930; photographer unknown; original filed as HE17/p7 in Audio-Visual Collection of Minnesota Historical Society, St. Paul; HANGAR AREA, INTERIOR, SHOWING LONGITUDINAL 'CARRYING' TRUSS AND CANTILEVERED SECTION OF ROOF TRUSSES; LOOKING NORTHWEST FROM SOUTHEAST FRONT CORNER - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  5. Wave Propagation Problems in Certain Elastic Anisotropic Half Spaces.

    DTIC Science & Technology

    1980-12-01

    874-882. 33. Paul , S.L., and Robinson, A.R., "Interaction of Plane Elastic Waves with a Cylindrical Cavity," Technical Documentary Report Mo. RTD...Professor Paul M. Naghdi University of California Department of Mechanical Engineering Berkeley, California 94720 Professor A. J. Durelli Oakland...Burt Paul University of Pennsylvania Towne School of Civil and Mechanical Engineering Philadelphia, Pennsylvania 19104 Professor H. W. Liu Syracuse

  6. 16TH Annual Review of Progress in Applied Computational Electromagnetics of the Naval Postgraduate School, Monterey, CA. Volume I

    DTIC Science & Technology

    2000-03-24

    Element Method for Designing Plasma Reactors" Leo Kempel, Paul Rummel, Tim Grotjohn and John Amrhein ............................................ 28...34Finite Element Method for Designing Plasma Reactors" Leo Kempel, Paul Rummel, Tim Grotjohn and John Amrhein...548 "lime-Domain Simulation of Electromagnetic Wave Propagation in a Magnetized Plasma" J. Paul , C. Christopoulos, and

  7. Ontonagon Harbor Operation and Maintenance Activities. Lake Superior.

    DTIC Science & Technology

    1975-08-01

    St. Paul, Minnesota 55101 August 1975 FINAL ENVIRONMENTAL IMPACT STATEMENT OPERATION AND MAINTENAN4CE ACTIVITIES ONTONAGON HARBDOR, MICHIGAN LAKE...SUPERIOR Responsible Office: St. Paul District, Corps of Engineers, 1135 U.S. Post Office and Custom House, St. Paul, Minnesota 55101 Telephone Number 612...Nonesuch shale is a finer siltstone containing recoverable copper deposits. Active mining is present at White Pine, 12 air miles southwest of Ontonagon

  8. Moral Perception and Judgment and a Truly Radical Change of Social Practices: A Reply to Paul Standish's "Registers of the Religious"

    ERIC Educational Resources Information Center

    Smeyers, Paul

    2012-01-01

    This article presents the author's response to Paul Standish's "Registers of the Religious". Addressing what he calls the "global", Paul Standish starts from MacIntyre's observation that people live in a world characterized by a vocabulary of value whose purchase on life is no longer authentically experienced: "MacIntyre's diagnosis of the…

  9. 38. Photographic copy of historic construction drawing, ink on linen, ...

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

    38. Photographic copy of historic construction drawing, ink on linen, February 1902 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Re- flooring and re-paving of Selby Avenue Bridge over tracks of Chicago, Milwaukee & St. Paul RY. CO. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  10. Effect of Nb on Delayed Fracture Resistance of Ultra-High Strength Martensitic Steels

    NASA Astrophysics Data System (ADS)

    Song, Rongjie; Fonstein, Nina; Pottore, Narayan; Jun, Hyun Jo; Bhattacharya, Debanshu; Jansto, Steve

    Ultra-high strength steels are materials of considerable interest for automotive and structural applications and are increasingly being used in those areas. Higher strength, however, makes steels more prone to hydrogen embrittlement (HE). The effects of Nb and other alloying elements on the hydrogen-induced delayed fracture resistance of cold rolled martensitic steels with ultra-high strength 2000 MPa were studied using an acid immersion test, thermal desorption analysis (TDA) and measuring of permeation. The microstructure was characterized by high resolution field emission Scanning Electron Microscopy (SEM) with Electron Backscattered Diffraction (EBSD) and Transmission Electron Microscopy (TEM). It was shown that the combined addition of Nb significantly improved the delayed fracture resistance of investigated steel. The addition of Nb to alloyed martensitic steels resulted in very apparent grain refinement of the prior austenite grain size. The Nb microalloyed steel contained a lower diffusible hydrogen content during thermal desorption analysis as compared to the base steel and had a higher trapped hydrogen amount after charging. The reason that Nb improved the delayed fracture resistance of steels can be attributed mostly to both hydrogen trapping and grain refinement.

  11. Photon-trapping microstructures enable high-speed high-efficiency silicon photodiodes

    NASA Astrophysics Data System (ADS)

    Gao, Yang; Cansizoglu, Hilal; Polat, Kazim G.; Ghandiparsi, Soroush; Kaya, Ahmet; Mamtaz, Hasina H.; Mayet, Ahmed S.; Wang, Yinan; Zhang, Xinzhi; Yamada, Toshishige; Devine, Ekaterina Ponizovskaya; Elrefaie, Aly F.; Wang, Shih-Yuan; Islam, M. Saif

    2017-04-01

    High-speed, high-efficiency photodetectors play an important role in optical communication links that are increasingly being used in data centres to handle higher volumes of data traffic and higher bandwidths, as big data and cloud computing continue to grow exponentially. Monolithic integration of optical components with signal-processing electronics on a single silicon chip is of paramount importance in the drive to reduce cost and improve performance. We report the first demonstration of micro- and nanoscale holes enabling light trapping in a silicon photodiode, which exhibits an ultrafast impulse response (full-width at half-maximum) of 30 ps and a high efficiency of more than 50%, for use in data-centre optical communications. The photodiode uses micro- and nanostructured holes to enhance, by an order of magnitude, the absorption efficiency of a thin intrinsic layer of less than 2 µm thickness and is designed for a data rate of 20 gigabits per second or higher at a wavelength of 850 nm. Further optimization can improve the efficiency to more than 70%.

  12. The design of novel visible light driven Ag/CdO as smart nanocomposite for photodegradation of different dye contaminants

    NASA Astrophysics Data System (ADS)

    Saravanakumar, K.; Muthuraj, V.; Jeyaraj, M.

    2018-01-01

    In this paper, we report a novel visible light driven Ag/CdO photocatalyst, fabricated for the first time via one pot hydrothermal method and further applied for the photodegradation of two important exemplar water contaminants, Malachite green and Acid Orange 7. The microstructure, composition and optical properties of Ag/CdO nanocomposites were thoroughly investigated by various techniques. Scanning electron microscopy clearly shows that Ag NPs were strongly embedded between the CdO nanoparticles. Among the series of synthesized Ag/CdO nanocomposites, (5%) Ag/CdO nanocomposite possesses enhanced photocatalytic activity. This result was attributed to the synergistic effect between Ag and CdO, and mainly Ag NPs can act as an electron trap site, which could reduce the recombination of the electron-hole and induce the visible light absorption. The active species trapping experiments implicate radOH and O2rad - radicals as the respective primary and secondary reactive species responsible for oxidative photodegradation of organic pollutants. On the basis of the results, a possible photocatalytic mechanism has also been proposed.

  13. Vitamin C supplementation and the common cold--was Linus Pauling right or wrong?

    PubMed

    Hemilä, H

    1997-01-01

    In 1970 Linus Pauling claimed that vitamin C prevents and alleviates the episodes of the common cold. Pauling was correct in concluding from trials published up till then, that in general vitamin C does have biological effects on the common cold, but he was rather over-optimistic as regards the size of benefit. His quantitative conclusions were based on a single placebo-controlled trial on schoolchildren in a skiing camp in the Swiss Alps, in which a significant decrease in common cold incidence and duration in the group administered 1 g/day of vitamin C was found. As children in a skiing camp are not a representative sample of the general population, Pauling's extrapolation to the population at large was too bold, erring as to the magnitude of the effect. Nevertheless, Pauling's general conclusion that vitamin C has physiological effects on the common cold is of major importance as it conflicts with the prevailing consensus that the only physiological effect of vitamin C on human beings is to prevent scurvy.

  14. A Demonstration to Assess Effectiveness, Suitability, and Survivability With the Missions and Means Framework

    DTIC Science & Technology

    2012-12-01

    A Demonstration to Assess Effectiveness, Suitability, and Survivability With the Missions and Means Framework by Beth S . Ward, Paul J...Tanenbaum, Keon U. Burley, Paul H. Deitz, Britt E. Bray, Richard S . Sandmeyer, and Jack H. Sheehan ARL-TR-6271 December 2012...Demonstration to Assess Effectiveness, Suitability, and Survivability With the Missions and Means Framework Beth S . Ward, Paul J. Tanenbaum, and Keon U

  15. Privilege: The Making of an Adolescent Elite at St. Paul's School. Princeton Studies in Cultural Sociology

    ERIC Educational Resources Information Center

    Khan, Shamus Rahman

    2012-01-01

    As one of the most prestigious high schools in the nation, St. Paul's School in Concord, New Hampshire, has long been the exclusive domain of America's wealthiest sons. But times have changed. Today, a new elite of boys and girls is being molded at St. Paul's, one that reflects the hope of openness but also the persistence of inequality. In…

  16. Magnetic and Structural Characterization of Fe-Ga Using Kerr Microscopy and Neutron Scattering

    DTIC Science & Technology

    2010-01-01

    117 4.6 Schematic of triple axes single crystal neutron diffractometer (left). TriCS intrument at Paul Scherrer Institut, Switzerland (right...Therefore, USANS data is one-dimensional. 4.3.3 Single Crystal Neutron Diffraction The single crystal neutron diffractometer, TriCS at Paul Scherrer...crystal neutron diffractometer (left). TriCS intrument at Paul Scherrer Institut, Switzerland (right) [106] 4.4 Unpolarized SANS In this section, SANS

  17. A Biophysical-Computational Perspective of Breast Cancer Pathogenesis and Treatment Response

    DTIC Science & Technology

    2008-03-01

    or for monitoring therapy responsiveness. In addition, we recently began a fruitful collaboration with Dr. Paul Hansma from UC Santa Barbara who has...Inactivation of the apoptotic effector Apaf-1 in malignant melanoma. Nature 409, 207-211 (2001). 44. Gifford, G., Paul , J., Vasey, P.A., Kaye, S.B...clustering. Data in parenthesis are 95% confidence intervals. Tissue Diagnostic Instrument Paul Hansma, Hongmei Yu, David Schultz, Azucena Rodriguez

  18. Changes in abundance of vascular plants under varying silvicultural systems at the Forest Ecosystem Research and Demonstration Area, Paul Smiths, New York

    Treesearch

    Mark J. Twery; Elizabeth Olson; Gary L. Wade; Michael. Rechlin

    2013-01-01

    The Forest Ecosystem Research and Demonstration Area (FERDA) was established in 1998 adjacent to the Visitor Interpretive Center (VIC) for the Adirondack Park in Paul Smiths, NY, to provide visitors with first-hand exposure to forest management activities and to provide research opportunities for scientists and students at Paul Smith's College. This research note...

  19. Multistage deformation of Au-quartz veins (Laurieras, French Massif Central): evidence for late gold introduction from microstructural, isotopic and fluid inclusion studies

    NASA Astrophysics Data System (ADS)

    Essarraj, S.; Boiron, M.-C.; Cathelineau, M.; Fourcade, S.

    2001-07-01

    The relative chronology of fluid migration, quartz and Au-deposition in a silicified fault from the main Au-district (Laurieras, St Yrieix district) from northern French Massif Central has been determined from microstructural, fluid inclusion, isotopic and ore mineral evidences. Three main stages of fluid circulation, microfracturing and quartz crystallization, and ore deposition were distinguished on the basis of textural relationships and the pressure, temperature and composition of the palaeo-fluids: (1) a series of early fluid events was responsible for the localized drainage of retrograde metamorphic fluids along the main fault and the subsequent sealing by milky and microcrystalline quartz preceeded the main Au-ore stages. Early fluids were aqueous-carbonic, trapped under lithostatic to sublithostatic pressures at temperatures in the range 350-500°C. Subsequently, several types of microstructures were developed in the early quartz matrix. (2) NS microfractures filled by clear quartz, arsenopyrite and boulangerite (I) contain significant refractory gold concentrations. Clear quartz formed from aqueous-carbonic fluids of lower densities than those of the earlier fluids. Significant pressure drops, down to pressures around 55 MPa were responsible for a local immiscibility of the aqueous-carbonic fluids at temperatures of 340±20°C. (3) The main ore stage is characterized by the formation of dense sets of sub-vertical (EW) microfractures, healed fluid inclusion planes in quartz, and filled by ore minerals (native gold, galena and boulangerite II) when they crosscut earlier sulfides. The fluids are aqueous with low and decreasing salinity, and probable trapping temperatures around 230°C. Isotopic data, obtained on microfissured quartz, indicate these dilute aqueous fluids may be considered as meteoric waters that deeply infiltrated the crust. Late microfissuring of a mesothermal quartz vein, originally barren (only with pyrite and arsenopyrite), appears to be the main factor controlling gold enrichment. It can be related to late Hercynian deformational stages, disconnected from the early fault formation and silicification. These late stages which affected the Hercynian basement during its uplift, are of critical importance for the formation of Au-ores. We concluded that this type of Au-ore formed under rather shallow conditions, is distinct from those generally described in most mesothermal Au-veins.

  20. Paul Bert

    NASA Technical Reports Server (NTRS)

    Colin, J.

    1978-01-01

    This biographical article on Paul Bert highlights his studies on the physiology of respiration and barometric pressure and, in particular his contributions to the understanding of hypoxia, hyperoxia and anesthesia.

  1. Paul Davis Restoration Information Sheet

    EPA Pesticide Factsheets

    Paul Davis Restoration (the Company) is located in Nicholasville, Kentucky. The settlement involves renovation activities conducted at a property constructed prior to 1978, located in Lexington, Kentucky.

  2. Modeling and Analysis of Resolve and Morale for the Long War’

    DTIC Science & Technology

    2007-12-01

    Alexandria, Virginia, 1995 Bratley, Paul , Bennett L. Fox, and Linus E. Schrage, A Guide to Simulation (2nd ed.), Springer-Verlag, New York, 1987 Bross... Paul J., Measuring the “Will to Fight” in Simulation, Lockheed Martin Corporation, 73rd MORS Symposium Working Group 33 Presentation, DTIC...115, 2004 MacKay, Niall, “Lanchester combat models”, Mathematics Today, Volume 42, Number 5, Pages 170-173, 2006 Macioce, Paul , “Viscoelastic

  3. Non-Lethal Weapons for Today’s Operations

    DTIC Science & Technology

    2011-01-01

    Division Chief Lieutenant Colonel Paul L. Scholl : paul.scholl@usmc.mil Acquisition Division Chief Kevin J. Swenson: kevin.swenson@usmc.mil Technology...Division Chief David B. Law: david.b.law1@usmc.mil Health Effects Officer Mary R. Williams : mary.r.williams1.ctr@usmc.mil Annual Report Editorial Board...Douglas J. Jerothe Lieutenant Colonel Paul L. Scholl Susan D. LeVine Kevin J. Swenson Kelley S. Hughes Alicia J. Owsiak Publication Management Bethel

  4. College and University Speech Codes in the Aftermath of R.A.V v. City of St. Paul.

    ERIC Educational Resources Information Center

    Fraleigh, Douglas

    In the case of RAV v. City of St. Paul, a teenager was charged with violating the city's Bias-Motivated Crime Ordinance after being accused of burning a cross inside the fenced yard of a black family. In a 9-0 decision, the Supreme Court struck down the St. Paul ordinance, a decision which raised a question as to whether many college and…

  5. Teaching to Make Disciples in a Higher Education Online Learning Environment: A Comparison of the Literature of Online Learning, the Objectives and Practices of Three Christian Colleges, and the Letters of Paul

    ERIC Educational Resources Information Center

    Morris, Raymond E.

    2012-01-01

    This dissertation explores engaging students in spiritual formation and discipleship in the online environment. This researcher begins with the proposition that the letters of Paul are examples of distance teaching and distance learning. The effectiveness of the letters of Paul in engaging their recipients in spiritual formation and discipleship…

  6. Development of a Robust Static Punch Experiment for Screening Unprocessed Ultra-High Molecular Weight Polyethylene (UHMWPE) Unidirectional Cross-Ply Material

    DTIC Science & Technology

    2014-09-01

    Cross-Ply Material by David Gray, Robert Kaste , and Paul Moy ARL-TR-7090 September 2014...Screening Unprocessed Ultra-High Molecular Weight Polyethylene (UHMWPE) Unidirectional Cross-Ply Material David Gray, Robert Kaste , and Paul...ELEMENT NUMBER 6. AUTHOR(S) David Gray, Robert Kaste , and Paul Moy 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7

  7. Space Weather Editors in Transition: Hail and Farewell

    NASA Astrophysics Data System (ADS)

    Knipp, Delores J.

    2017-02-01

    I hope you will join me in welcoming Dr. Daniel Welling of University of Michigan and Dr. T. Paul O'Brien of the Aerospace Corporation to the Space Weather (SWE) editorial team. Dan and Paul have answered the call to fill the shoes of two departing editors: Dr. Howard Singer and Dr. Barbara Giles. Dan brings insight related to space weather model development, while Paul brings expertise in the geospace radiation environment.

  8. Thin film silicon by a microwave plasma deposition technique: Growth and devices, and, interface effects in amorphous silicon/crystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Jagannathan, Basanth

    Thin film silicon (Si) was deposited by a microwave plasma CVD technique, employing double dilution of silane, for the growth of low hydrogen content Si films with a controllable microstructure on amorphous substrates at low temperatures (<400sp°C). The double dilution was achieved by using a Ar (He) carrier for silane and its subsequent dilution by Hsb2. Structural and electrical properties of the films have been investigated over a wide growth space (temperature, power, pressure and dilution). Amorphous Si films deposited by silane diluted in He showed a compact nature and a hydrogen content of ˜8 at.% with a photo/dark conductivity ratio of 10sp4. Thin film transistors (W/L = 500/25) fabricated on these films, showed an on/off ratio of ˜10sp6 and a low threshold voltage of 2.92 volts. Microcrystalline Si films with a high crystalline content (˜80%) were also prepared by this technique. Such films showed a dark conductivity ˜10sp{-6} S/cm, with a conduction activation energy of 0.49 eV. Film growth and properties have been compared for deposition in Ar and He carrier systems and growth models have been proposed. Low temperature junction formation by undoped thin film silicon was examined through a thin film silicon/p-type crystalline silicon heterojunctions. The thin film silicon layers were deposited by rf glow discharge, dc magnetron sputtering and microwave plasma CVD. The hetero-interface was identified by current transport analysis and high frequency capacitance methods as the key parameter controlling the photovoltaic (PV) response. The effect of the interface on the device properties (PV, junction, and carrier transport) was examined with respect to modifications created by chemical treatment, type of plasma species, their energy and film microstructure interacting with the substrate. Thermally stimulated capacitance was used to determine the interfacial trap parameters. Plasma deposition of thin film silicon on chemically clean c-Si created electron trapping sites while hole traps were seen when a thin oxide was present at the interface. Under optimized conditions, a 10.6% efficient cell (11.5% with SiOsb2 A/R) with an open circuit voltage of 0.55 volts and a short circuit current density of 30 mA/cmsp2 was fabricated.

  9. Nanocrystalline ZnON; High mobility and low band gap semiconductor material for high performance switch transistor and image sensor application

    PubMed Central

    Lee, Eunha; Benayad, Anass; Shin, Taeho; Lee, HyungIk; Ko, Dong-Su; Kim, Tae Sang; Son, Kyoung Seok; Ryu, Myungkwan; Jeon, Sanghun; Park, Gyeong-Su

    2014-01-01

    Interest in oxide semiconductors stems from benefits, primarily their ease of process, relatively high mobility (0.3–10 cm2/vs), and wide-bandgap. However, for practical future electronic devices, the channel mobility should be further increased over 50 cm2/vs and wide-bandgap is not suitable for photo/image sensor applications. The incorporation of nitrogen into ZnO semiconductor can be tailored to increase channel mobility, enhance the optical absorption for whole visible light and form uniform micro-structure, satisfying the desirable attributes essential for high performance transistor and visible light photo-sensors on large area platform. Here, we present electronic, optical and microstructural properties of ZnON, a composite of Zn3N2 and ZnO. Well-optimized ZnON material presents high mobility exceeding 100 cm2V−1s−1, the band-gap of 1.3 eV and nanocrystalline structure with multiphase. We found that mobility, microstructure, electronic structure, band-gap and trap properties of ZnON are varied with nitrogen concentration in ZnO. Accordingly, the performance of ZnON-based device can be adjustable to meet the requisite of both switch device and image-sensor potentials. These results demonstrate how device and material attributes of ZnON can be optimized for new device strategies in display technology and we expect the ZnON will be applicable to a wide range of imaging/display devices. PMID:24824778

  10. Novel back-reflector architecture with nanoparticle based buried light-scattering microstructures for improved solar cell performance

    NASA Astrophysics Data System (ADS)

    Desta, Derese; Ram, Sanjay K.; Rizzoli, Rita; Bellettato, Michele; Summonte, Caterina; Jeppesen, Bjarke R.; Jensen, Pia B.; Tsao, Yao-Chung; Wiggers, Hartmut; Pereira, Rui N.; Balling, Peter; Larsen, Arne Nylandsted

    2016-06-01

    A new back-reflector architecture for light-management in thin-film solar cells is proposed that includes a morphologically smooth top surface with light-scattering microstructures buried within. The microstructures are pyramid shaped, fabricated on a planar reflector using TiO2 nanoparticles and subsequently covered with a layer of Si nanoparticles to obtain a flattened top surface, thus enabling growth of good quality thin-film solar cells. The optical properties of this back-reflector show high broadband haze parameter and wide angular distribution of diffuse light-scattering. The n-i-p amorphous silicon thin-film solar cells grown on such a back-reflector show enhanced light absorption resulting in improved external quantum efficiency. The benefit of the light trapping in those solar cells is evidenced by the gains in short-circuit current density and efficiency up to 15.6% and 19.3% respectively, compared to the reference flat solar cells. This improvement in the current generation in the solar cells grown on the flat-topped (buried pyramid) back-reflector is observed even when the irradiation takes place at large oblique angles of incidence. Finite-difference-time-domain simulation results of optical absorption and ideal short-circuit current density values agree well with the experimental findings. The proposed approach uses a low cost and simple fabrication technique and allows effective light manipulation by utilizing the optical properties of micro-scale structures and nanoscale constituent particles.

  11. Annual Continuation And Progress Report For Low-Energy Nuclear Physics Research At Lawrence Livermore National Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scielzo, N. D.; Wu, C.

    2015-10-27

    (I)In this project, the Beta-­decay Paul Trap, an open-­geometry RFQ ion trap that can be instrumented with sophisticated radiation detection arrays, is used for precision β-­decay studies. Measurements of β-­decay angular correlations, which are sensitive to exotic particles and other phenomena beyond the Standard Model (SM) of particle physics that may occur at the TeV-­energy scale, are being performed by taking advantage of the favorable properties of the mirror 8Li and 8B β ± decays and the benefits afforded by using trapped ions. By detecting the β and two α particles emitted in these decays, the complete kinematics can bemore » reconstructed. This allows a simultaneous measurement of the β-­n, β-­n-­α, and β-α correlations and a determination of the neutrino energy and momentum event by event. In addition, the 8B neutrino spectrum, of great interest in solar neutrino oscillation studies, can be determined in a new way. Beta-­delayed neutron spectroscopy is also being performed on neutron-­rich isotopes by studying the β-­decay recoil ions that emerge from the trap with high efficiency, good energy resolution, and practically no backgrounds. This novel technique is being used to study isotopes of mass-­number A~130 in the vicinity of the N=82 neutron magic number to help understand the rapid neutron-­capture process (r-­process) that creates many of the heavy isotopes observed in the cosmos. (II)A year-long CHICO2 campaign at ANL/ATLAS together with GRETINA included a total of 10 experiments, seven with the radioactive beams from CARIBU and three with stable beams, with 82 researchers involved from 27 institutions worldwide. CHICO2 performed flawlessly during this long campaign with achieved position resolution matching to that of GRETINA, which greatly enhances the sensitivity in the study of nuclear γ-­ray spectroscopy. This can be demonstrated in our results on 144Ba and 146Ba where the octupole deformation is evident from the measured B(E3; 3 -→0 +) strengths that significantly greater than the theoretical predictions. We anticipate that CHICO2 will continue to be a viable charged-­particle detector for the research need of the low-­energy nuclear physics community.« less

  12. The Mobilization of Effort: Sergeants, Patrol Officers, and Productivity in an American Agency.

    DTIC Science & Technology

    1982-02-01

    Berlceley. Cain, M. 1974 Society and the policeman’s role. London: Routledge and Kegan Paul. Chatterton, Michael 1975 Organizational relationships and...Routledge and Kegan Paul. Pike, D. 1981 A comparative analysis of the role of women in police training. Unpublished Ph.D. Dissertation, Yale University...David 1970 Yhe theory of organization. NY: Basic. 1974 ()rranizational work. London: Root ledge and Kegan Paul. Van Maanen , lo’in 1972 Pledging the

  13. Life Cycle Management Commands: Wartime Process or Long-Term Solution?

    DTIC Science & Technology

    2007-03-31

    this memorandum. • 1998: The Director of the Army Acquisition Corps (AAC), Lieutenant General (LTG) Paul Kern, testified before Congress about two...the Army finally determined that PVS did not benefit the Army overall. 17 The Director of the Army Acquisition Corps (AAC), LTG Paul Kern, championed...2 and 3 on pages 10 and 11 of the study. 9 LTG Paul J. Kern, Military Deputy to the ASA(ALT), comments made to the Army Acquisition Corps (AAC

  14. Minutes of the Explosives Safety Seminar (19th) Held at Los Angeles, California, 9-10-11 September 1980. Volume 1

    DTIC Science & Technology

    1980-01-01

    DOUBLE-BASE EXTRUSION COMPOSITIONS ................................... 89 Messrs. Craig E. Johnson and Paul F. Dendor V I GUN PROPELLANT PROPAGATION IN...Mullins and C. F. Baker RESULTS AND ANALYSIS OF STRENGTHENED STEEL BUILDING BLAST TESTS ..... 165 Messrs. Frederic E. Sock, Norval Dobbs, Paul Price and...347 Mr. J. Paul Glenn I viLR SESSION - EXPLOSION CONTAIMENT & VENTING Moderator - Mr. Irving Forsten EXPLOSION CONTAINMENT VESSELS AND M4TERIALS

  15. Another Crossroads? Professional Military Education Two Decades After the Goldwater-Nichols Act and the Skelton Panel

    DTIC Science & Technology

    2010-04-01

    staff including Erin Conaton, Paul Arcangeli, Robert Simmons, Paul Oostburg Sanz, Paul Lewis, Debra Wada, Suzanne McKenna, Vickie Plunkett, Craig ...National Defense University: Lieutenant General Frances C. Wilson, Dr. John Deegan , Jr., and Dr. John W. Yaeger, 16 March 2009. Marine Corps...diversity.” The Washington Post (on line), 10 November 2009. Deegan , John, Jr. “First Step to Academic Excellence: The Faculty.” 14 April 2009

  16. The Inadequacy of Definition and the Utility of a Theory of Hybrid Conflict: Is the Hybrid Threat New?

    DTIC Science & Technology

    2012-05-17

    Era of Persistent Conflict, edited by Paul Brister, William H. Natter III, & Robert R. Tomes, 60-69. Washington, DC: CENSA, 2011. Gott, Kendall G...Conflict.” In Hybrid Warfare and Transnational Threats: Perspectives for an Era of Persistent Conflict, edited by Paul Brister, William H. Natter...Hybrid Warfare and Transnational Threats: Perspectives for an Era of Persistent Conflict, edited by Paul Brister, William H. Natter III, & Robert R

  17. Welcoming nora: a family event.

    PubMed

    Walsh, Allison J; Walsh, Paul R; Walsh, Jane M; Walsh, Gavin T

    2011-01-01

    In this column, Allison and Paul Walsh share the story of the birth of Nora, their third baby and their second child to be born at home. Allison and Paul share their individual memories of labor and birth. But their story is only part of the story of Nora's birth. Nora's birth was a family event, with Allison and Paul's other children very much part of the experience. Jane and Gavin share their own memories of their baby sister's birth.

  18. Short of General War: Perspectives on the Use of Military Power in the 21st Century

    DTIC Science & Technology

    2010-04-01

    Paul , MN: Zenith Press, 2004. Hammes’ work is one articulation of this argument. 5. United States Joint Forces Command, “The JOE 2008, Joint Operating...this approach would actually be counterproductive and might be more harmful than beneficial to American interests. According to Paul Sanders, 18...A New Security Strategy for America, Washington, DC: Brookings Institution Press, 1999, p. 55. 50. Paul J. Sanders, “Not the Way to Intervene

  19. Enhancing the Effectiveness of Ad Hoc Units: A Revised Training Model

    DTIC Science & Technology

    2009-06-01

    thank Dr. Kalev “Gunner” Sepp, Dr. Bob McNab, Dr. John Arquilla, Dr. Nancy Roberts, Dr. Susan Hocevar, and Dr. Dorothy Denning for providing their...also want to thank Colonel Paul Warren, Information Operations Branch Chief at U.S. Central Command – Special Operations (SOCCENT), for sponsoring my...Academy of Management Journal, 38 (1), 60-84. Paul M. Nemiroff, Paul M., William, A. Pasmore and David L. Ford, Jr., “The Effects of Two

  20. The first 'molecular disease': a story of Linus Pauling, the intellectual patron.

    PubMed

    Gormley, Melinda

    2007-06-01

    In November 1949, chemist Linus Pauling and three colleagues published an article on sickle-cell anemia, a study that opened up new and exciting possibilities for research into such 'molecular diseases'. Even before this celebrated publication appeared in Science, Pauling foresaw its potential benefits and announced it as a medical breakthrough: '... our structural chemistry and understanding of molecules is getting to the point where it should be of assistance in converting medicine into a real science' [Guiles, R. (1949) Discovery of blood disease called key to cancer research. The Detroit Times 13 Sep 1949, Newspaper Clippings 1949n.18, Pauling Papers.]. Their discovery--that this debilitating disorder was caused by an abnormal form of hemoglobin--was borne out of a rich mix of expertise, from Pauling's remarkable intuition to the careful experimental chemistry of his student Harvey A. Itano. It also relied upon technological innovation: a custom-made electrophoresis machine housed at the California Institute of Technology was the perfect tool to reveal fundamental chemical differences between normal and abnormal forms of hemoglobin. Not only did this work establish a new way of looking at inherited diseases, it also stimulated the mass production of the electrophoresis machine as an essential investigative and diagnostic tool. A close inspection of this case study illustrates just how Pauling ran his laboratory and helps to explain how one man could achieve so much over his lifetime.

  1. Paul Feyerabend: Science and the Anarchist.

    ERIC Educational Resources Information Center

    Science, 1979

    1979-01-01

    Presents comments on the arguments of Paul Feyerabend toward progression science. The positions held by this philosopher of science are given with accompanying remarks from other philosophers and historians. (SA)

  2. Paul G. Silver (1948-2009)

    NASA Astrophysics Data System (ADS)

    Solomon, Sean C.

    2009-11-01

    A pioneer in the novel application of seismic observations to infer the flow field of Earth's mantle and the mechanics of fault zones, Paul Gordon Silver tragically was killed on 7 August in an automobile accident that also took the life of his 22-year-old daughter, Celine. Born and raised in Los Angeles, Calif., Paul received all of his degrees from the University of California. Following receipt of a B.A. in psychology from the University of California (UC), Los Angeles (1970), he pursued a career as a musician for several years. Drawn to Earth science, Paul obtained a B.A. in geology from UC Berkeley, in 1976, and he was recruited by Tom Jordan (now at the University of Southern California) to the graduate program of the Scripps Institution of Oceanography at UC San Diego.

  3. Major Additions to the Linus Pauling Canon

    NASA Astrophysics Data System (ADS)

    Davenport, Derek A.

    2002-08-01

    The National Library of Medicine has also just posted a Web site on Linus Pauling in its Profiles of Science series. While by no means as rich as the various Oregon State University sites, it is well worth visiting. There are texts of various speeches (including his Nobel address), many downloadable photographs, correspondence (including a poignant letter to James Watson and Francis Crick concerning their "rival" structures for DNA), and much else besides. There is a certain irony in Linus Pauling being honored by the National Library of Medicine. Ever since his 1949 presidential address to the American Chemical Society, and perhaps earlier, Pauling had been at loggerheads, sometimes acrimoniously so, with the medical establishment. It is easy to imagine him somewhere in the timeless infinitude of the empyrean sporting his characteristic ear-to-ear grin.

  4. Shock Deformation and Volcanism across the Cretaceous - Transition.

    NASA Astrophysics Data System (ADS)

    Huffman, Alan Royce

    1990-01-01

    The cause of the Cretaceous-Tertiary (K/T) transition remains one of the most controversial scientific topics in the geosciences. Geological and geophysical evidence associated with the K/T boundary have been used to argue that the extinctions were caused by meteor impact or volcanism. The goal of this study was to assess the viability of a volcanic model for the K/T transition. Comparison of natural and experimentally-shocked quartz and feldspar using optical and transmission electron microscopy (TEM) revealed that the optical and statistical character of shock-induced microstructures in volcanic rocks are different from both classic impact microstructures, and from the Raton K/T samples. A series of 31 high-explosive (HE) shock-recovery experiments at pressures to 25 GPa and temperatures to 750^circC were completed on samples of granite and quartzite. TEM and optical microscopy reveal that pre-shock temperature and pulse duration have a first-order effect on the development of shock-induced microstructures in quartz and feldspar. Application of the experimental results to natural shock-induced microstructures indicates that the volcanic microstructures are probably produced at elevated temperatures and shock pressures that do not exceed 15 GPa. The results also suggest that the Raton K/T deposits were produced at pressures below about 25 GPa. Analysis of samples from the K/T transition at DSDP Site 527 and correlations between biostratigraphy, isotopes, and the data from this study suggest that the decline in marine productivity over an extended period of time may be due to climate changes induced by basaltic volcanism. The eruption of the Deccan Traps is a viable mechanism for the K/T extinctions, and the correlation of flood basalts with every major biotic crisis in the last 250 Ma supports the link between these two phenomena. Eruption of flood basalts enriched in F, Cl, CO_2 , and SO_2, could disrupt the terrestrial ecosystem, and could produce effects including elevated pCO_2, acid rain, ozone depletion, lower ocean alkalinity, and climatic change, which can explain the observation of stepped or gradual extinction.

  5. 78 FR 62357 - Sunshine Act Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-21

    ..., filing of petitions and applications and agency #0;statements of organization and functions are examples... interested in obtaining more information should contact Paul Kollmer-Dorsey at (202) 203-4545. Paul Kollmer...

  6. Keynote Address: When Breath Becomes Air-As Physician Becomes Patient.

    PubMed

    Kalanithi, Lucy; Wakelee, Heather; Carlson, Robert W

    2017-05-01

    As part of the NCCN 22nd Annual Conference: Improving the Quality, Effectiveness, and Efficiency of Cancer Care, Lucy Kalanithi, MD, wife of now-deceased best-selling author Paul Kalanithi ( When Breath Becomes Air ), and Heather Wakelee, MD, Paul's oncologist, discussed-for the first time together in a public forum-Paul's experience of going from a neurosurgery resident to a patient with cancer with a terminal diagnosis. Robert Carlson, MD, moderated the discussion. Copyright © 2017 by the National Comprehensive Cancer Network.

  7. 25. Photocopy of aerial photograph dated May 1930; J. E. ...

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

    25. Photocopy of aerial photograph dated May 1930; J. E. Quigley, Photographer; original filed as MR2.9/SP8/p355 in Audio-visual Collection of Minnesota Historical Society, St. Paul; SHOWS RECENTLY COMPLETED NORTHWEST HANGAR AND ADMINISTRATION BUILDING I N UPPER LEFT (THREE-QUARTER VIEW OF WEST SIDE AND SOUTH FRONT); ALSO SHOWS THE SIMILARLY DESIGNED MUNICIPAL HANGAR UNDER CONSTRUCTION IN FOREGROUND; LOOKING NORTHEAST - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  8. Proceedings of the Conference on the Design of Experiments in Army Research Development and Testing (34th) Held in Las Cruces, New Mexico on 19-21 October 1988

    DTIC Science & Technology

    1989-07-01

    Webb and Linda L.C. Moss.............,,...,....., 27 COMPARISON OF RELIABILITY CONFIDENCE INTERVALS Paul H . Thrasher. ......... . 0 1...Webb and Linda L.C. Moss, U.S. Army Ballistic Research Laboratory COMPARISON OF RELIABILITY CONFIDENCE INTERVALS Paul H. Thrasher, White Sands Missile...RELEVANT Paul H. Thrasher, White Sands Missile Range 0930 - 1000 BREAK 1000 - 1130 GENERAL SESSION III Chairperson: Douglas B. Tang, Valter Reed Army

  9. A Comparative Analysis of Army Physical Readiness Test Results of AMEDD Units Without Formal Physical Training Programs

    DTIC Science & Technology

    1984-06-01

    Paul C.; Albrink , Margaret J.; and Krall, John M. "Exercise Effects on Fitness,, Lipids, Glucose Tolerance and Insulin Levels in Young Adults...1982): 14-15. Shepherd, Roy J.; Corey, Paul; Renzland, Peter; and Cox Michael . "The Impact of Changes in Fitness and Lifestyle Upon Health Care...Utilization." Canadian Journal of Public Health 74 (January/February 1983): 51-55. Shepherd, Roy J.; Corey, Paul; Renzland, Peter; and Cox, Michael . "The

  10. Final Environmental Impact Statement. Ontonagon Harbor Operation and Maintenance Activities. Ontonagon County, Michigan.

    DTIC Science & Technology

    1975-08-01

    Paul, Minnesota 55101 August 1975 ,.’U * - S • S S S S S • S U U FIN"L ENVIRONMENTAL IMPACT STATEMENT OPERATION AND MAINTENANCE ACTIVITIES ONTONAGON...HARBOR, MICHIGAN LAKE SUPERIOR Responsible Office: St. Paul District, Corps of Engineers, 1135 U.S. Post Office and Custom House, St. Paul, Minnesota ... mining is present at White Pine, 12 air miles southwest of Ontonagon Harbor. 6 2.130 Topography. - The area’s topography is directly related to the

  11. Aerodynamic Optimization of a Supersonic Bending Body Projectile by a Vector-Evaluated Genetic Algorithm

    DTIC Science & Technology

    2016-12-01

    Evaluated Genetic Algorithm prepared by Justin L Paul Academy of Applied Science 24 Warren Street Concord, NH 03301 under contract W911SR...Supersonic Bending Body Projectile by a Vector-Evaluated Genetic Algorithm prepared by Justin L Paul Academy of Applied Science 24 Warren Street... Genetic Algorithm 5a. CONTRACT NUMBER W199SR-15-2-001 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Justin L Paul 5d. PROJECT

  12. STS 41-G crew prepares to leave Operations and checkout bldg for launch

    NASA Image and Video Library

    1984-10-05

    41G-90081 / S17-90081 (5 Oct 1984) --- The seven member crew leaves the Operations and Checkout Building (OCB) to take a van ride to the launch pad. Leading the way is Kathryn D. Sullivan followed in file by Robert L. Crippen, Paul D. Scully-Power and Jon A. McBride. On the right side are Sally K. Ride, David C. Leestma and Marc Garneau. Trailing the crew are George W. S. Abbey, Richard Nygren, Paul Bulver, and Paul J. Weitz.

  13. Paul D. Sturkie: Avian cardiac physiologist.

    PubMed

    Bello, Nicholas T; Cohick, Wendie S; McKeever, Kenneth H; Malinowski, Karyn

    2018-06-01

    Sturkie's Avian Physiology is a highly regarded textbook for the study of comparative poultry physiology. Less well known, however, is the contribution of Paul D. Sturkie (1909-2002) as a pioneer in the experimental physiology of avian species. His seminal research on the cardiovascular and hemodynamic controls of chickens and egg-laying hens had a notable impact on the poultry industry and breeding practices of farmers. The purpose of this article is to highlight the contributions and practical insights of Paul D. Sturkie to the field of poultry science.

  14. Paul Oil Company, Inc. Consent Agreements and Proposed Final Orders

    EPA Pesticide Factsheets

    Proposed settlements, recorded in two Consent Agreements and Final Orders (“Proposed Consent Agreements”), between EPA and Paul Oil Company, Inc., to resolve two civil administrative penalty proceedings.

  15. 5. Historic American Buildings Survey Paul J. F. Schumacher, Photographer ...

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

    5. Historic American Buildings Survey Paul J. F. Schumacher, Photographer September 1957 FRONT and WEST SIDE ELEVATIONS - Sacred Heart Mission, Interstate 90 & Interchange 39, Cataldo, Shoshone County, ID

  16. Paul Lampe/McGarry Houghton | Division of Cancer Prevention

    Cancer.gov

    Project Title/Research Areas: Hybrid Plasma Markers that Complement CT Imaging for Early Lung Cancer DetectionPrincipal Investigator/Institution:  Paul Lampe/McGarry Houghton, Fred Hutchinson Cancer Research Center |

  17. Paul Dirac

    NASA Astrophysics Data System (ADS)

    Pais, Abraham; Jacob, Maurice; Olive, David I.; Atiyah, Michael F.

    2005-09-01

    Preface Peter Goddard; Dirac memorial address Stephen Hawking; 1. Paul Dirac: aspects of his life and work Abraham Pais; 2. Antimatter Maurice Jacob; 3. The monopole David Olive; 4. The Dirac equation and geometry Michael F. Atiyah.

  18. Paul Dirac

    NASA Astrophysics Data System (ADS)

    Pais, Abraham; Jacob, Maurice; Olive, David I.; Atiyah, Michael F.

    1998-02-01

    Preface Peter Goddard; Dirac memorial address Stephen Hawking; 1. Paul Dirac: aspects of his life and work Abraham Pais; 2. Antimatter Maurice Jacob; 3. The monopole David Olive; 4. The Dirac equation and geometry Michael F. Atiyah.

  19. Elongated unique DNA strand deposition on microstructured substrate by receding meniscus assembly and capillary force

    PubMed Central

    Charlot, B.; Bardin, F.; Sanchez, N.; Roux, P.; Teixeira, S.; Schwob, E.

    2014-01-01

    Ordered deposition of elongated DNA molecules was achieved by the forced dewetting of a DNA solution droplet over a microstructured substrate. This technique allows trapping, uncoiling, and deposition of DNA fragments without the need of a physicochemical anchoring of the molecule and results in the combing of double stranded DNA from the edge of microwells on a polydimethylsiloxane (PDMS) substrate. The technique involves scanning a droplet of DNA solution caught between a movable blade and a PDMS substrate containing an array of microwells. The deposition and elongation appears when the receding meniscus dewets microwells, the latter acting here as a perturbation in the dewetting line forcing the water film to break locally. Thus, DNA molecules can be deposited in an ordered manner and elongated conformation based solely on a physical phenomenon, allowing uncoiled DNA molecules to be observed in all their length. However, the exact mechanism that governs the deposition of DNA strands is not well understood. This paper is an analysis of the physical phenomenon occurring in the deposition process and is based on observations made with the use of high frame/second rate video microscopy. PMID:24753724

  20. Photodissociation Spectroscopy of Cold Protonated Synephrine: Surprising Differences between IR-UV Hole-Burning and IR Photodissociation Spectroscopy of the O-H and N-H Modes.

    PubMed

    Nieuwjaer, N; Desfrançois, C; Lecomte, F; Manil, B; Soorkia, S; Broquier, M; Grégoire, G

    2018-04-19

    We report the UV and IR photofragmentation spectroscopies of protonated synephrine in a cryogenically cooled Paul trap. Single (UV or IR) and double (UV-UV and IR-UV) resonance spectroscopies have been performed and compared to quantum chemistry calculations, allowing the assignment of the lowest-energy conformer with two rotamers depending on the orientation of the phenol hydroxyl (OH) group. The IR-UV hole burning spectrum exhibits the four expected vibrational modes in the 3 μm region, i.e., the phenol OH, C β -OH, and two NH 2 + stretches. The striking difference is that, among these modes, only the free phenol OH mode is active through IRPD. The protonated amino group acts as a proton donor in the internal hydrogen bond and displays large frequency shifts upon isomerization expected during the multiphoton absorption process, leading to the so-called IRMPD transparency. More interestingly, while the C β -OH is a proton acceptor group with moderate frequency shift for the different conformations, this mode is still inactive through IRPD.

  1. Fast Dynamical Decoupling of the Mølmer-Sørensen Entangling Gate.

    PubMed

    Manovitz, Tom; Rotem, Amit; Shaniv, Ravid; Cohen, Itsik; Shapira, Yotam; Akerman, Nitzan; Retzker, Alex; Ozeri, Roee

    2017-12-01

    Engineering entanglement between quantum systems often involves coupling through a bosonic mediator, which should be disentangled from the systems at the operation's end. The quality of such an operation is generally limited by environmental and control noise. One of the prime techniques for suppressing noise is by dynamical decoupling, where one actively applies pulses at a rate that is faster than the typical time scale of the noise. However, for boson-mediated gates, current dynamical decoupling schemes require executing the pulses only when the boson and the quantum systems are disentangled. This restriction implies an increase of the gate time by a factor of sqrt[N], with N being the number of pulses applied. Here we propose and realize a method that enables dynamical decoupling in a boson-mediated system where the pulses can be applied while spin-boson entanglement persists, resulting in an increase in time that is at most a factor of π/2, independently of the number of pulses applied. We experimentally demonstrate the robustness of our entangling gate with fast dynamical decoupling to σ_{z} noise using ions in a Paul trap.

  2. Proton Transports in Pure Liquid Water Characterized by Melted Ice Lattice Model

    NASA Astrophysics Data System (ADS)

    Jie, Binbin; Sah, Chihtang

    Basic water properties have not been understood for 200 years. Our Melted Ice Lattice model accounts for the 2 basic properties of pure water, the ion product (pH) and mobilities. It has HCP primitive unit cells, each with 4H2O, based on the 1933 Bernal-Fowler model, verified by 1935 Pauling residual entropy theory of 1928-1935 Giauque experimental low temperature specific heat measurements. Our 2 ion species are point-mass protons p + and p-, for mass and electricity transport. Three protonic thermal activation energies are obtained from pH and p + and p- mobilities vs T (0-100OC). Proton transport is analyzed in 3 proton-phonon collision steps: proton detrapping by protonic phonon absorption, proton scattering by oxygenic (water) phonons, and proton trapping with protonic phonon emission. Distinction between Potential and Kinetic Energy Bands of protons (Fermions) and phonons (Bosons) is noted. Experimental protonic activation energies are the phonon energies given by the spring-mass vibration frequencies of lattice, wn = (kn/mn)1/2 . n is the proton-mass unit of the synchronized vibrating particles in the primitive unit cells.

  3. 13. Photocopy of photograph mounted on Christmas card (from St. ...

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

    13. Photocopy of photograph mounted on Christmas card (from St. Paul's Church) Photographer unknown 1906 INTERIOR LOOKING EAST - St. Paul's Episcopal Church, 120 East J Street, Benicia, Solano County, CA

  4. 18. MAINTENANCE SHOP, FIRST FLOOR, INTERIOR, ENGINE AND AIRPLANE OVERHAUL ...

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

    18. MAINTENANCE SHOP, FIRST FLOOR, INTERIOR, ENGINE AND AIRPLANE OVERHAUL AREAS; LOOKING EAST - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  5. 17. MAINTENANCE SHOP, FIRST FLOOR, INTERIOR, ENGINE AND AIRPLANE OVERHAUL ...

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

    17. MAINTENANCE SHOP, FIRST FLOOR, INTERIOR, ENGINE AND AIRPLANE OVERHAUL AREAS; LOOKING WEST. - Northwest Airways Hangar & Administration Building, 590 Bayfield Street, St. Paul Downtown Airport (Holman), Saint Paul, Ramsey County, MN

  6. ARC-2002-ACD02-0055-04

    NASA Image and Video Library

    2002-03-20

    Sun-Earth Day WEBCAST - NASA TV; Host Paul Mortfield, Astronomer Stanford Solar Center and visiting students from San Francisco Bay Area Schools Documentation Technology Branch Video communications van (code-JIT) David Maurantonio, Paul Langston

  7. Catalytic creativity. The case of Linus Pauling.

    PubMed

    Nakamura, J; Csikszentmihalyi, M

    2001-04-01

    This article illustrates how creativity is constituted by forces beyond the innovating individual, drawing examples from the career of the eminent chemist Linus Pauling. From a systems perspective, a scientific theory or other product is creative only if the innovation gains the acceptance of a field of experts and so transforms the culture. In addition to this crucial selective function vis-à-vis the completed work, the social field can play a catalytic role, fostering productive interactions between person and domain throughout a career. Pauling's case yields examples of how variously the social field contributes to creativity, shaping the individual's standards of judgment and providing opportunities, incentives, and critical evaluation. A formidable set of strengths suited Pauling for his scientific achievements, but examination of his career qualifies the notion of a lone genius whose brilliance carries the day.

  8. Brotherly Advice: Letters from Hugo to Paul Ehrenfest in his Final Years

    NASA Astrophysics Data System (ADS)

    Halpern, Paul

    2006-03-01

    At the start of the 1930s, theoretician Paul Ehrenfest spent much of his time traveling through America and Europe while engaged in a steady stream of lectures. This traveling phase coincided with a frantic and intense period of negative self-examination, financial difficulty, and various other personal concerns that would ultimately lead to his 1933 suicide. Throughout these final years, he kept up a steady correspondence with his brother Hugo, a physician based in Saint Louis. Ten years older than Paul, Hugo freely doled out frank psychological advice about subjects ranging from the proper treatment of children to the dangers of self-pity. Through a look at some of the letters exchanged between the two brothers, this talk will examine the role Hugo played during the dark final years of Paul Ehrenfest's life.

  9. The use of GIS for monitoring and predicting urban growth in east and west St Paul, Winnipeg, Manitoba, Canada.

    PubMed

    Hathout, S

    2002-11-01

    Most urban growth in Canada occurs in the urban-rural fringe. The increasing dispersal of the Canadian urban population is due to centrifugal forces pulling urbanites past the suburbs into the surrounding exurban communities. Most Canadian urban centres are located on prime agricultural land. Exurban sprawl devours an inordinate amount of the better agricultural land. The growth around the city of Winnipeg is a case in point. Within Winnipeg's urban field are the rural municipalities of East and West St Paul. The objective of this study is to investigate the impact of urban growth on the agricultural land of these RMs as well as the rate of urban growth in both Municipalities based on database analysis using aerial photographs taken in 1960 and 1989 and Geographic Information System (GIS). East St Paul was found to have a higher rate of urbanization (from 10.14% to 43.75%) between 1960 and 1989 than West St Paul (from 7.36% to 23.57%). The growth prediction using Markov probability chain analysis showed that East St Paul will henceforth experience a reduced rate of increase than West St Paul. The rate of urbanization for both RMs is found to be comparable with areas surrounding other major cities such as Toronto. The largest increases in urban land use categories occurred in and around the existing exurban settlements. It was found that most urbanization take place on the most fertile soil.

  10. Control of Y-211 content in bulk YBCO superconductors fabricated by a buffer-aided, top seeded infiltration and growth melt process

    NASA Astrophysics Data System (ADS)

    Namburi, Devendra K.; Shi, Yunhua; Palmer, Kysen G.; Dennis, Anthony R.; Durrell, John H.; Cardwell, David A.

    2016-03-01

    Bulk (RE)-Ba-Cu-O ((RE)BCO, where RE stands for rare-earth), single grain superconductors can trap magnetic fields of several tesla at low temperatures and therefore can function potentially as high field magnets. Although top seeded melt growth (TSMG) is an established process for fabricating relatively high quality single grains of (RE)BCO for high field applications, this technique suffers from inherent problems such as sample shrinkage, a large intrinsic porosity and the presence of (RE)2BaCuO5 (RE-211)-free regions in the single grain microstructure. Seeded infiltration and growth (SIG), therefore, has emerged as a practical alternative to TSMG that overcomes many of these problems. Until now, however, the superconducting properties of bulk materials processed by SIG have been inferior to those fabricated using the TSMG technique. In this study, we identify that the inferior properties of SIG processed bulk superconductors are related to the presence of a relatively large Y-211 content (˜41.8%) in the single grain microstructure. Controlling the RE-211 content in SIG bulk samples is particularly challenging because it is difficult to regulate the entry of the liquid phase into the solid RE-211 preform during the infiltration process. In an attempt to solve this issue, we have investigated the effect of careful control of both the infiltration temperature and the quantity of liquid phase powder present in the sample preforms prior to processing. We conclude that careful control of the infiltration temperature is the most promising of these two process variables. Using this knowledge, we have fabricated successfully a YBCO bulk single grain using the SIG process of diameter 25 mm that exhibits a trapped field of 0.69 T at 77 K, which is the largest value reported to date for a sample fabricated by the SIG technique.

  11. How Energy Efficiency is Adding Jobs in St. Paul, Minnesota

    ScienceCinema

    Hannigan, Jim; Coleman, Chris; Oliver, LeAnn; Jambois, Louis

    2018-02-07

    Saint Paul, Minnesota is using an energy efficiency grant to provide commercial retrofits that will allow a local produce distribution company to dramatically reduce its energy costs and add dozens of new workers.

  12. Route-Specific Transit Marketing in Minneapolis/St. Paul, MN

    DOT National Transportation Integrated Search

    1985-10-01

    The Minneapolis/St. Paul Transit Marketing Demonstration involved the administration of a combination of marketing techniques on five selected transit routes. The approach employed differed from most previous marketing demonstrations in that 1) prici...

  13. JAFCO d/b/a Paul Davis Restoration and Remodeling Information Sheet

    EPA Pesticide Factsheets

    JAFCO d/b/a Paul Davis Restoration and Remodeling (the Company) is located in Memphis, Tennessee. The settlement involves renovation activities conducted at property constructed prior to 1978, located in Memphis, Tennessee.

  14. How Energy Efficiency is Adding Jobs in St. Paul, Minnesota

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hannigan, Jim; Coleman, Chris; Oliver, LeAnn

    2011-01-01

    Saint Paul, Minnesota is using an energy efficiency grant to provide commercial retrofits that will allow a local produce distribution company to dramatically reduce its energy costs and add dozens of new workers.

  15. High-temperature studies of grain boundaries in ultrafine grained alloys by means of positron lifetime

    NASA Astrophysics Data System (ADS)

    Würschum, R.; Shapiro, E.; Dittmar, R.; Schaefer, H.-E.

    2000-11-01

    Atomic free volumes and vacancies in the ultrafine grained alloys Pd84Zr16, Cu 0.1 wt % ZrO2, and Fe91Zr9 were studied by means of positron lifetime. The thermally stable microstructures serve as a novel type of model system for studying positron trapping and annihilation as well as the thermal behavior of vacancy-sized free volumes over a wide temperature range up to ca. 1200 K by making use of a metallic 58Co positron source. In ultrafine grained Cu the thermal formation of lattice vacancies could be observed. In Pd84Zr16 an increase of the specific positron trapping rate of nanovoids and, in addition, detrapping of positrons from free volumes with a mean size slightly smaller than one missing atom in the grain boundaries contributes to a reversible increase of the positron lifetime of more than 60 ps with measuring temperature. In Fe91Zr9 similar linear high-temperature increases of the positron lifetime are observed in the nanocrystalline and the amorphous state. The question of thermal vacancy formation in grain boundaries is addressed taking into account the different types of interface structures of the present alloys.

  16. The design of novel visible light driven Ag/CdO as smart nanocomposite for photodegradation of different dye contaminants.

    PubMed

    Saravanakumar, K; Muthuraj, V; Jeyaraj, M

    2018-01-05

    In this paper, we report a novel visible light driven Ag/CdO photocatalyst, fabricated for the first time via one pot hydrothermal method and further applied for the photodegradation of two important exemplar water contaminants, Malachite green and Acid Orange 7. The microstructure, composition and optical properties of Ag/CdO nanocomposites were thoroughly investigated by various techniques. Scanning electron microscopy clearly shows that Ag NPs were strongly embedded between the CdO nanoparticles. Among the series of synthesized Ag/CdO nanocomposites, (5%) Ag/CdO nanocomposite possesses enhanced photocatalytic activity. This result was attributed to the synergistic effect between Ag and CdO, and mainly Ag NPs can act as an electron trap site, which could reduce the recombination of the electron-hole and induce the visible light absorption. The active species trapping experiments implicate OH and O 2 - radicals as the respective primary and secondary reactive species responsible for oxidative photodegradation of organic pollutants. On the basis of the results, a possible photocatalytic mechanism has also been proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Studies on the effects of helium on the microstructural evolution of V-3.8Cr-3.9Ti

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doraiswamy, N.; Kestel, B.; Alexander, D.E.

    1997-04-01

    The favorable physical and mechanical properties of V-3.8Cr-3.9Ti (wt.%), when subjected to neutron irradiation, has lead to considerable attention being focused on it for use in fusion reactor structural applications. However, there is limited data on the effects of helium on physical and mechanical properties of this alloy. Understanding these effects are important since helium will be generated by direct {alpha}-injection or transmutation reactions in the fusion environment, typically at a rate of {approx}5 appm He/dpa. Helium has been shown to cause substantial embrittlement, even at room temperature in vanadium and its alloys. Recent simulations of the fusion environment usingmore » the Dynamic Helium Charging Experiments (DHCE) have also indicated that the mechanical properties of vanadium alloys are altered by the presence of helium in post irradiation tests performed at room temperature. While the strengths were lower, room temperature ductilities of the DHCE specimens were higher than those of non-DHCE specimens. These changes have been attributed to the formation of different types of hardening centers in these alloys due to He trapping. Independent thermal desorption experiments suggest that these hardening centers may be associated with helium-vacancy-X (where X = O, N, and C) complexes. These complexes are stable below 290{degrees}C and persist at room temperature. However, there has been no direct microstructural evidence correlating the complexes with irradiation effects. An examination of the irradiation induced microstructure in samples preimplanted with He to different levels would enable such a correlation.« less

  18. Effects of nanostructuring on luminescence properties of SrS:Ce,Sm phosphor: An experimental and phenomenological study

    NASA Astrophysics Data System (ADS)

    Yazdanmehr, Mohsen; Sadeghi, Hossein; Tehrani, Masoud Kavosh; Hashemifar, Seyed Javad; Mahdavi, Mohammad

    2018-01-01

    In this work, we employ various experimental techniques to illustrate the effects of nanostructuring on improvement of the luminescence properties of the polycrystalline SrS co-activated by cerium and samarium dopants (SrS : Ce , Sm). The nano and microstructure SrS : Ce , Sm powders were synthesized by the co-precipitation and solid state diffusion methods, respectively, followed by the spark plasma sintering (SPS) process to densify powders into pellet shape. It is observed that the photo-luminescence (PL), radio-luminescence (RL), and optically stimulated luminescence (OSL) emission intensity of the nanostructure samples are significantly improved with respect to the microstructure samples. Moreover, by using an accurate photomultiplier tube, we measured the CW-OSL decay curves of the samples to demonstrate much higher and faster sensitivity of the nanostructure SrS : Ce , Sm for in-flight and online OSL radiation dosimetry. The obtained absorption and emission spectra are used for phenomenology of the electronic band structure of the SrS : Ce , Sm micro and nano-phosphors inside the band gap. The proposed phenomenological electronic structures are then used to clarify the role of Ce3+ and Sm3+ localized energy levels in the luminescence properties of the nano and microstructure samples. It is argued that electronic transitions from the 2T2g state of Ce3+ and the 4G5/2 state of Sm3+ have strong contribution to the PL and RL emission spectra, while in the OSL mechanism, the Sm3+ 4G5/2 state is mainly responsible for electrons trapping.

  19. 11. Photocopy of 1906 photograph. Glass negative in Paul A. ...

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

    11. Photocopy of 1906 photograph. Glass negative in Paul A. Kohl's office, Missouri Botanical Garden. CLOSE VIEW OF LINNAEUS BUST - Missouri Botanical Garden, Linnaean House, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  20. 76 FR 8656 - Safety Zone; Miami International Triathlon, Bayfront Park, Miami, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ...-mail Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A.Steiner@uscg.mil . If you have questions on viewing the docket, call Renee V...

  1. Coastal Imaging Spectroscopy

    DTIC Science & Technology

    2006-09-30

    Year, Semi-Finalist, Florida Environmental Research Institute, W. Paul Bissett, Ph.D., Executive Director, Greater Tampa Chamber of Commerce . 2004...Small Business of the Year, -Finalist, Florida Environmental Research Institute, W. Paul Bissett, Ph.D., Executive Director, Greater Tampa Chamber of Commerce .

  2. Sun-Earth Day WEBCAST - NASA TV; Host Paul Mortfield, Astronomer Stanford Solar Center and visiting

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Sun-Earth Day WEBCAST - NASA TV; Host Paul Mortfield, Astronomer Stanford Solar Center and visiting students from San Francisco Bay Area Schools Documentation Technology Branch Video communications van (code-JIT)

  3. Paul Hill d/b/a Alternative Energy Windows and Siding

    EPA Pesticide Factsheets

    Paul Hill d/b/a Alternative Energy Windows and Siding (the Company) is located in Concord, New Hampshire. The settlement involves renovation activities conducted at property constructed prior to 1978, located in Concord, New Hampshire.

  4. Senate Confirmation Hearing IG

    NASA Image and Video Library

    2009-10-14

    Paul K. Martin, nominee for Inspector General for NASA, answers questions during his confirmation hearing in front of the Senate Committee on Commerce, Science and Transportation, Thursday, Oct. 15, 2009, on Capitol Hill in Washington. Photo Credit: (NASA/Paul E. Alers)

  5. Quantum simulation of interacting spin models with trapped ions

    NASA Astrophysics Data System (ADS)

    Islam, Kazi Rajibul

    The quantum simulation of complex many body systems holds promise for understanding the origin of emergent properties of strongly correlated systems, such as high-Tc superconductors and spin liquids. Cold atomic systems provide an almost ideal platform for quantum simulation due to their excellent quantum coherence, initialization and readout properties, and their ability to support several forms of interactions. In this thesis, I present experiments on the quantum simulation of long range Ising models in the presence of transverse magnetic fields with a chain of up to sixteen ultracold 171Yb+ ions trapped in a linear radio frequency Paul trap. Two hyperfine levels in each of the 171Yb+ ions serve as the spin-1/2 systems. We detect the spin states of the individual ions by observing state-dependent fluorescence with single site resolution, and can directly measure any possible spin correlation function. The spin-spin interactions are engineered by applying dipole forces from precisely tuned lasers whose beatnotes induce stimulated Raman transitions that couple virtually to collective phonon modes of the ion motion. The Ising couplings are controlled, both in sign and strength with respect to the effective transverse field, and adiabatically manipulated to study various aspects of this spin model, such as the emergence of a quantum phase transition in the ground state and spin frustration due to competing antiferromagnetic interactions. Spin frustration often gives rise to a massive degeneracy in the ground state, which can lead to entanglement in the spin system. We detect and characterize this frustration induced entanglement in a system of three spins, demonstrating the first direct experimental connection between frustration and entanglement. With larger numbers of spins we also vary the range of the antiferromagnetic couplings through appropriate laser tunings and observe that longer range interactions reduce the excitation energy and thereby frustrate the ground state order. This system can potentially be scaled up to study a wide range of fully connected spin networks with a few dozens of spins, where the underlying theory becomes intractable on a classical computer.

  6. 12. Photocopy of 1906 photograph. Glass negative in Paul A. ...

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

    12. Photocopy of 1906 photograph. Glass negative in Paul A. Kohl's office, Missouri Botanical Garden. BUST OF ASA GRAY AT SOUTH ENTRANCE - Missouri Botanical Garden, Linnaean House, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  7. 13. Photocopy of 1906 photograph. Glass negative in Paul A. ...

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

    13. Photocopy of 1906 photograph. Glass negative in Paul A. Kohl's office, Missouri Botanical Garden. BUST OF THOMAS NUTTALL AT SOUTH ENTRANCE - Missouri Botanical Garden, Linnaean House, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  8. RadNet Air Data From St. Paul, MN

    EPA Pesticide Factsheets

    This page presents radiation air monitoring and air filter analysis data for St. Paul, MN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  9. Meet EPA Ecologist Paul Mayer, Ph.D.

    EPA Pesticide Factsheets

    EPA ecologist Paul Mayer, Ph.D. works in EPA's Groundwater and Ecosystem Restoration division where he studies riparian zones (the area along rivers and streams where the habitats are influenced by both the land and water) and stream restoration

  10. Revised Mulliken Electronegativities I. Calculation and Conversion to Pauling Units.

    ERIC Educational Resources Information Center

    Bratsch, Steven G.

    1988-01-01

    Discusses a revision and extension of the Mulliken electronegativity scale to consider 50 elements. Describes the calculation of valence-state promotion energies and Mulliken atomic electronegativities and the conversion of Mulliken electronegativities to Pauling units. (CW)

  11. Publications - GMC 219 | Alaska Division of Geological & Geophysical

    Science.gov Websites

    Paul G. Benedum Nulato Unit #1 well Authors: Murphy, J.M. Publication Date: 1993 Publisher: Alaska , Apatite fission track data of cuttings (1,000-11,500') from the Paul G. Benedum Nulato Unit #1 well

  12. Characterization of microbial structures in Setul Limestone

    NASA Astrophysics Data System (ADS)

    Ezanie, A. S. Mohamad; Aziz, A. Che; Roslan, M. Kamal

    2018-04-01

    Setul Limestone in Langgun Island and Perlis are lack of sedimentary structures, which makes it difficult for paleoenvironmental study in the study area. The present study of limestone succession at Kaki Bukit and Teluk Mempelam area focuses on microbial related structure in order to constraint its depositional setting. The structures were identified as stromatolites and thrombolites, which resulted from the interaction of microbial with sediments by trapping, binding and/or precipitation of minerals. Both structures can be distinguished based on four main classifications, the megastructure, macrostructure, mesostructure and microstructure scales. These classifications assist in understanding its physical natures and lead to the recognition of paleoenvironment in the study area which is believed to be controlled by several factors such as environment, hydrodynamic, biological and chemical processes.

  13. Near unity ultraviolet absorption in graphene without patterning

    NASA Astrophysics Data System (ADS)

    Zhu, Jinfeng; Yan, Shuang; Feng, Naixing; Ye, Longfang; Ou, Jun-Yu; Liu, Qing Huo

    2018-04-01

    Enhancing the light-matter interaction of graphene is an important issue for related photonic devices and applications. In view of its potential ultraviolet applications, we aim to achieve extremely high ultraviolet absorption in graphene without any nanostructure or microstructure patterning. By manipulating the polarization and angle of incident light, the ultraviolet power can be sufficiently coupled to the optical dissipation of graphene based on single-channel coherent perfect absorption in an optimized multilayered thin film structure. The ultraviolet absorbance ratios of single and four atomic graphene layers are enhanced up to 71.4% and 92.2%, respectively. Our research provides a simple and efficient scheme to trap ultraviolet light for developing promising photonic and optoelectronic devices based on graphene and potentially other 2D materials.

  14. Bioinspired super-antiwetting interfaces with special liquid-solid adhesion.

    PubMed

    Liu, Mingjie; Zheng, Yongmei; Zhai, Jin; Jiang, Lei

    2010-03-16

    Super-antiwetting interfaces, such as superhydrophobic and superamphiphobic surfaces in air and superoleophobic interfaces in water, with special liquid-solid adhesion have recently attracted worldwide attention. Through tuning surface microstructures and compositions to achieve certain solid/liquid contact modes, we can effectively control the liquid-solid adhesion in a super-antiwetting state. In this Account, we review our recent progress in the design and fabrication of these bioinspired super-antiwetting interfaces with special liquid-solid adhesion. Low-adhesion superhydrophobic surfaces are biologically inspired, typically by the lotus leaf. Wettability investigated at micro- and nanoscale reveals that the low adhesion of the lotus surface originates from the composite contact mode, a microdroplet bridging several contacts, within the hierarchical structures. Recently high-adhesion superhydrophobic surfaces have also attracted research attention. These surfaces are inspired by the surfaces of gecko feet and rose petals. Accordingly, we propose two biomimetic approaches for the fabrication of high-adhesion superhydrophobic surfaces. First, to mimic a sticky gecko's foot, we designed structures with nanoscale pores that could trap air isolated from the atmosphere. In this case, the negative pressure induced by the volume change of sealed air as the droplet is pulled away from surface can produce a normal adhesive force. Second, we constructed microstructures with size and topography similar to that of a rose petal. The resulting materials hold air gaps in their nanoscale folds, controlling the superhydrophobicity in a Wenzel state on the microscale. Furthermore, we can tune the liquid-solid adhesion on the same superhydrophobic surface by dynamically controlling the orientations of microstructures without altering the surface composition. The superhydrophobic wings of the butterfly (Morpho aega) show directional adhesion: a droplet easily rolls off the surface of wings along one direction but is pinned tightly against rolling in the opposite direction. Through coordinating the stimuli-responsive materials and appropriate surface-geometry structures, we developed materials with reversible transitions between a low-adhesive rolling state and a high-adhesive pinning state for water droplets on the superhydrophobic surfaces, which were controlled by temperature and magnetic and electric fields. In addition to the experiments done in air, we also demonstrated bioinspired superoleophobic water/solid interfaces with special adhesion to underwater oil droplets and platelets. In these experiments, the high content of water trapped in the micro- and nanostructures played a key role in reducing the adhesion of the oil droplets and platelets. These findings will offer innovative insights into the design of novel antibioadhesion materials.

  15. Measurement of the magnetic interaction between two bound electrons of two separate ions.

    PubMed

    Kotler, Shlomi; Akerman, Nitzan; Navon, Nir; Glickman, Yinnon; Ozeri, Roee

    2014-06-19

    Electrons have an intrinsic, indivisible, magnetic dipole aligned with their internal angular momentum (spin). The magnetic interaction between two electronic spins can therefore impose a change in their orientation. Similar dipolar magnetic interactions exist between other spin systems and have been studied experimentally. Examples include the interaction between an electron and its nucleus and the interaction between several multi-electron spin complexes. The challenge in observing such interactions for two electrons is twofold. First, at the atomic scale, where the coupling is relatively large, it is often dominated by the much larger Coulomb exchange counterpart. Second, on scales that are substantially larger than the atomic, the magnetic coupling is very weak and can be well below the ambient magnetic noise. Here we report the measurement of the magnetic interaction between the two ground-state spin-1/2 valence electrons of two (88)Sr(+) ions, co-trapped in an electric Paul trap. We varied the ion separation, d, between 2.18 and 2.76 micrometres and measured the electrons' weak, millihertz-scale, magnetic interaction as a function of distance, in the presence of magnetic noise that was six orders of magnitude larger than the magnetic fields the electrons apply on each other. The cooperative spin dynamics was kept coherent for 15 seconds, during which spin entanglement was generated, as verified by a negative measured value of -0.16 for the swap entanglement witness. The sensitivity necessary for this measurement was provided by restricting the spin evolution to a decoherence-free subspace that is immune to collective magnetic field noise. Our measurements show a d(-3.0(4)) distance dependence for the coupling, consistent with the inverse-cube law.

  16. Hepatitis B Shots Are Recommended for All New Babies

    MedlinePlus

    ... Centers for Disease Control and Prevention Saint Paul, Minnesota • 651-647-9009 • www. immunize. org • www. vaccineinformation. ... Centers for Disease Control and Prevention Saint Paul, Minnesota • 651-647-9009 • www.immunize.org • www.vaccineinformation. ...

  17. 79. Photocopy of photograph (original print in the Minnesota Historical ...

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

    79. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, ca. 1890, #741.) ALEXANDER RAMSEY HOUSE, ca. 1890 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  18. 76. Photocopy of photograph (original print in the Minnesota Historical ...

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

    76. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1860. #22358.) UPPER LEVEE FROM CHESTNUT STREET, 1860 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  19. 74. Photocopy of photograph (original print in the Minnesota Historical ...

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

    74. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1896. #35105.) FIRST ROBERT STREET BRIDGE, ca. 1896 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  20. Paul Carlson | Center for Cancer Research

    Cancer.gov

    Paul Carlson, Ph.D. March 28 Principal Investigator Laboratory of Mucosal Pathogens and Cellular Immunology Center for Biologics Evaluation and Research (CBER), FDA Topic:  "Research and Regulation of novel biologic products at the FDA's Center for Biologics Evaluation and Research"

  1. St. Paul central corridor study : Pierce Butler industrial redevelopment parkway

    DOT National Transportation Integrated Search

    2003-07-01

    At present, development in the St. Paul Central Corridor is occurring piecemeal and lacks an integrative vision. This study's aim was to devise design approaches that create a district which integrates light industrial job creation and retention with...

  2. 27. Photocopy of August 25, 1921 photograph by Paul A. ...

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

    27. Photocopy of August 25, 1921 photograph by Paul A. Kohl. Glass Negative Box IX, Tower Grove, Missouri Botanical Garden. ITALIAN GARDEN BY JOHN NOYES, LOOKING WEST - Missouri Botanical Garden, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  3. 76 FR 29642 - Special Local Regulations; Miami Super Boat Grand Prix, Miami Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-23

    ... INFORMATION CONTACT: If you have questions on this rule, call or e-mail Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A.Steiner@uscg.mil . If...

  4. 77 FR 48497 - Sunshine Act Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-14

    ...--Yes Michael Meehan--Yes Dennis Mulhaupt--Yes Dana Perino--Yes Tara Sonenshine--Yes Statements from... Maryjean Buhler, Chief Financial Officer Paul Kollmer-Dorsey, Deputy General Counsel and Board Secretary... CONTACT PERSON FOR MORE INFORMATION: Persons interested in obtaining more information should contact Paul...

  5. STS-134 Tweetup

    NASA Image and Video Library

    2011-04-28

    Heather Paul, a project engineer for Johnson Space Center, talks about space suit technology during the STS-134 Tweetup, Thursday, April 28, 2011, at Kennedy Space Center in Cape Canaveral, Fla. About 150 NASA Twitter followers attended the event. Photo Credit: (NASA/Paul E. Alers)

  6. Minutes of the Explosives Safety Seminar (22nd) Held in Anaheim, California on 26-28 August 1986. Volume 1

    DTIC Science & Technology

    1986-08-01

    105 Paul D. Smith and Theodore R. Crawford BL.AST VENTING FROM A (UIBICLE 119 Y. Kivity and S. Fellur PRESSURE/TEMPERATURE DECAY IN I11 EXPLOSION...EFFECTIVENESS OF TH 5-1300 CUBICLES ADDED TO EXISTING 201 BUILDINGS Paul M. LaHoudc DESKTOP COWffRS AND EXPLOSIVE SAFU 239 John M.Ftrritto OPTIMAL DESIGN OF...EXPLOSIVES saFwlY ON READINESS - THE 799 PRICE OF SAFETY " BG Paul L. Greenberg N) NAVAL ARMAMENT DEW FUR THE ROYAL MUMALIAN NAVY 805 Comm -W k-wroughs

  7. Diagnostic Interference: People’s Use of Information in Incomplete Bayesian World Problems

    DTIC Science & Technology

    1990-07-01

    them was the one who did it. Stephen and Paul are 5 year old twins. One afternoon their mother hired a new babysitter so she could go out to do errands...Paul broke the lamp? _ Reliability. Stephen’s and Paul’s mother enjoys dressing them alike. Before she left, she had said to the babysitter " New ...complementarity); and it one already has a degree of belief p(H) in proposition H, and one is given new evidence E pertinent to the truth of H, one can use a

  8. Headache classification and the Bible: Was St Paul's thorn in the flesh migraine?

    PubMed

    Göbel, H; Isler, H; Hasenfratz, H P

    1995-06-01

    The conversion of Saul to Paul was a major event in the history of Western culture. Compared with its impact, any medical comments may seem redundant, but they have kept their place in the literature for many centuries. The flashing light that caused Saul to fall is often explained as solar retinopathy or keratitis, a seizure, or even a hysterical fit. These interpretations propose either a trivial injury or disease that would interfere with mental health. Neither version is quite compatible with the dramatic dimension of the event and with Paul's later achievements and sufferings. In later years, Paul became a great manager, preacher and writer who was able to carry on under any kind of duress, though not without very painful reactions. He was suffering from bouts of unilateral headache, and also from a chronic eye condition which gave great trouble to his followers but did not cause lasting damage; the descriptions fulfil the criteria for migraine without aura of the 1988 Headache Classification. If the flashing light that caused Paul to fall down is interpreted as a visual migraine aura, with the additional symptoms of "not seeing" or photophobia and anorexia, it falls into place with his later history of migraine.

  9. Influence of ZnO doping on the properties of single domain YBCO bulks fabricated by RE+011 TSIG process

    NASA Astrophysics Data System (ADS)

    Yang, W. M.; Yuan, X. C.; Guo, Y. X.

    2017-10-01

    Single domain YBCO bulk superconductors with different additions of ZnO have been successfully fabricated by RE+011 TSIG process with a new solid phase of [(100-x)(Y2O3 + 1.2BaCuO2)+xZnO] and a new liquid phase of (Y2O3+6CuO+10BaCuO2). The effects of ZnO additions on the growth morphology, microstructure, critical temperature (Tc), the levitation force and trapped field of the YBCO bulks have been investigated. It is found that within the range of ZnO additions x=0-1.0 wt.%, all the samples are of the typical characteristic of single-domain YBCO bulk; the Tc of the samples decreases from 92 K to 80 K when the ZnO addition x increases from x=0 wt.% to x=1.0 wt.%; the levitation force and trapped field of the samples firstly increase and then decrease with increase of ZnO additions after going through a maximum, which is closely related with the ZnO addition and the resulting flux pinning force caused by lattice distortion due to the substitution of Zn2+ for Cu2+ site in the YBCO crystal; the largest levitation force 36.8 N (77 K, 0.5 T) and trapped field 0.416 T (77 K, 0.5 T) of the samples are obtained when x=0.1 wt.%, respectively. This result is significantly important and helpful for us to improve the properties of YBCO bulk superconductors.

  10. Processing/structure/property Relationships of Barium Strontium Titanate Thin Films for Dynamic Random Access Memory Application.

    NASA Astrophysics Data System (ADS)

    Peng, Cheng-Jien

    The purpose of this study is to see the application feasibility of barium strontium titanate (BST) thin films on ultra large scale integration (ULSI) dynamic random access memory (DRAM) capacitors through the understanding of the relationships among processing, structure and electrical properties. Thin films of BST were deposited by multi-ion -beam reactive sputtering (MIBERS) technique and metallo -organic decomposition (MOD) method. The processing parameters such as Ba/Sr ratio, substrate temperature, annealing temperature and time, film thickness and doping concentration were correlated with the structure and electric properties of the films. Some effects of secondary low-energy oxygen ion bombardment were also examined. Microstructures of BST thin films could be classified into two types: (a) Type I structures, with multi-grains through the film thickness, for amorphous as-grown films after high temperature annealing, and (b) columnar structure (Type II) which remained even after high temperature annealing, for well-crystallized films deposited at high substrate temperatures. Type I films showed Curie-von Schweidler response, while Type II films showed Debted type behavior. Type I behavior may be attributed to the presence of a high density of disordered grain boundaries. Two types of current -voltage characteristics could be seen in non-bombarded films depending on the chemistry of the films (doped or undoped) and substrate temperature during deposition. Only the MIBERS films doped with high donor concentration and deposited at high substrate temperature showed space-charge -limited conduction (SCLC) with discrete shallow traps embedded in trap-distributed background at high electric field. All other non-bombarded films, including MOD films, showed trap-distributed SCLC behavior with a slope of {~}7.5-10 due to the presence of grain boundaries through film thickness or traps induced by unavoidable acceptor impurities in the films. Donor-doping could significantly improve the time -dependent dielectric breakdown (TDDB) behavior of BST thin films, mostly likely due to the lower oxygen vacancy concentration resulted from donor-doping.

  11. Low temperature fabrication of CuxO thin-film transistors and investigation on the origin of low field effect mobility

    NASA Astrophysics Data System (ADS)

    Shijeesh, M. R.; Jayaraj, M. K.

    2018-04-01

    Cuprous (Cu2O) and cupric (CuO) oxide thin films have been deposited by radio frequency magnetron sputtering with two different oxygen partial pressures. The as-deposited copper oxide films were subjected to post-annealing at 300 °C for 30 min to improve the microstructural, morphological, and optical properties of thin films. Optical absorption studies revealed the existence of a large number of subgap states inside CuO films than Cu2O films. Cu2O and CuO thin film transistors (TFTs) were fabricated in an inverted staggered structure by using a post-annealed channel layer. The field effect mobility values of Cu2O and CuO TFTs were 5.20 × 10-4 cm2 V-1 s-1 and 2.33 × 10-4 cm2 V-1 s-1, respectively. The poor values of subthreshold swing, threshold voltage, and field effect mobility of the TFTs were due to the charge trap density at the copper oxide/dielectric interface as well as defect induced trap states originated from the oxygen vacancies inside the bulk copper oxide. In order to study the distribution of the trap states in the Cu2O and CuO active layer, the temperature dependent transfer characteristics of transistors in the temperature range between 310 K and 340 K were studied. The observed subgap states were found to be decreasing exponentially inside the bandgap, with CuO TFT showing higher subgap states than Cu2O TFT. The high-density hole trap states in the CuO channel are one of the plausible reasons for the lower mobility in CuO TFT than in Cu2O TFT. The origin of these subgap states was attributed to the impurities or oxygen vacancies present in the CuO channel layer.

  12. 77. Photocopy of photograph (original print in the Minnesota Historical ...

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

    77. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1859. #377. Photographer: Illingworth.) LOWER LEVEE FROM JACKSON STREET, 1859 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  13. 65. Photocopy of photograph (original print in the Minnesota Historical ...

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

    65. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1889. #37682.) VIEW TO NORTH, SHOWING SPAN NOS. 6-24, 1889 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  14. 69. Photocopy of photograph (original print in the Minnesota Historical ...

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

    69. Photocopy of photograph (original print in the Minnesota Historical society, St. Paul, Minnesota, 1984. #32375.) VIEW TO WEST, SHOWING DAMAGED BRIDGE AFTER CYCLONE. 1904. - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  15. 77 FR 20820 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... Trust, and Gloria Foley, all of Lovington, Illinois, and Paul Michael Hrvol, Jr. and Paul Michael Hrvol... Bancorp, Inc. and thereby indirectly control Hardware State Bank, both of Lovington, Illinois. Board of...

  16. 44. Photograph of original sketch by Paul Cloyd, Historical Architect, ...

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

    44. Photograph of original sketch by Paul Cloyd, Historical Architect, Denver Service Center, National Park Service, Denver, Colorado, dated March 1985. EVOLUTION OF GRAND CANYON WATER RECLAMATION PLANT AS IT STANDS TODAY. - Water Reclamation Plant, Grand Canyon, Coconino County, AZ

  17. Physical and Biological Modes of Thought in the Chemistry of Linus Pauling

    NASA Astrophysics Data System (ADS)

    Nye, Mary Jo

    No figure in modern chemistry better exemplifies than Linus Pauling (1901-1994) the intersections of the scientific disciplines of chemistry, physics, and biology nor the roles of physical and biological modes of thought in the 'central science' of chemistry.

  18. 1. Photocopy of photograph (original print #17 located in ...

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

    1. Photocopy of photograph (original print #17 - located in Pope & Talbot Archives. Port Gamble, WA). Unknown Photographer, September 1906. View of St. Paul's Episcopal Church, facing southwest from Rainier Avenue. - St. Paul's Episcopal Church, Rainier Avenue, Port Gamble, Kitsap County, WA

  19. 28. Photocopy of August 25, 1921 photograph by Paul A, ...

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

    28. Photocopy of August 25, 1921 photograph by Paul A, Kohl. Glass Negative Box IX, Tower Grove, Missouri Botanical Garden. ITALIAN GARDEN AND FLORAL DISPLAY HOUSE, LOOKING NORTH - Missouri Botanical Garden, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  20. 73. Photocopy of photograph (original print in the Minnesota Historical ...

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

    73. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1867. #MR2.9 SP4.2/rll.) FIRST WABASHA STREET BRIDGE, 1867 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  1. 66. Photocopy of photograph (original print in the Minnesota Historical ...

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

    66. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, ca. 1925. #19657.) VIEW TO NORTHWEST, SHOWING SPAN NOS. 21 TO 26 - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  2. 75 FR 38770 - Siskiyou, OR Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    .... Written comments should be sent to Paul Galloway, Medford Interagency Office, 3040 Biddle Road, Medford... facilitate entry into the building. FOR FURTHER INFORMATION CONTACT: Paul Galloway, Acting Public Affairs... the opportunity to address the Committee during that session. Dated: June 24, 2010. Scott D. Conroy...

  3. Parallel Narrative Structure in Paul Harding's "Tinkers"

    ERIC Educational Resources Information Center

    Çirakli, Mustafa Zeki

    2014-01-01

    The present paper explores the implications of parallel narrative structure in Paul Harding's "Tinkers" (2009). Besides primarily recounting the two sets of parallel narratives, "Tinkers" also comprises of seemingly unrelated fragments such as excerpts from clock repair manuals and diaries. The main stories, however, told…

  4. Line Designs Inspired by Paul Klee

    ERIC Educational Resources Information Center

    Blanchette, Lisa

    2009-01-01

    In this lesson, students learn about line, shape, color, mixed media and abstraction, while being introduced to Swiss artist, Paul Klee (1879-1940). This lesson works well with a variety of age levels and abilities and could also be used to teach analogous or triad color schemes.

  5. Electron Microscopy of Tungsten Disulphide Inorganic Nanomaterials

    DTIC Science & Technology

    2009-09-01

    cylindrical molecule similar to a carbon nanotube. Inorganic nanotubes have been observed in some mineral deposits. Linus Pauling suggested the...diffraction pattern was due to the carbon coating. Figure 6 SAED taken from the single nanotube shown in figure 5 REFERENCES 1. Pauling , L; "The

  6. View of the PAVE PAWS radar from approach along Spencer ...

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

    View of the PAVE PAWS radar from approach along Spencer Paul Road, looking northwest - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  7. Predicting Upwelling Radiance on the West Florida Shelf

    DTIC Science & Technology

    2005-09-30

    Business of the Year, Florida Environmental Research Institute, W. Paul Bissett, Ph.D., Executive Director, Greater Tampa Chamber of Commerce . Finalist...2004 Small Business of the Year, Florida Environmental Research Institute, W. Paul Bissett, Ph.D., Executive Director, Greater Tampa Chamber of Commerce . 9

  8. In Memoriam: Paul J. Lioy

    EPA Science Inventory

    Exposure Science has lost one of its founders and intellectual champions. Dr. Paul Lioy unexpectedly passed away on July 8, 2015 at the age of 68 years. The world has been left a far better place thanks to Dr. Lioy’s vision and creativity, enormous scientific contributions,...

  9. Colloquy to Paul Musset

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2007-12-13

    En honneur de Paul Musset il a été décidé de faire plutôt un colloque scientifique à la place d'une cérémonie. Plusieurs personnes temoignent de leurs estime et amitié pour ce physicien et ses activités

  10. 76 FR 1532 - Determinations of Attainment by the Applicable Attainment Date for the Hayden, Nogales, Paul Spur...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-11

    ... indicated that we plan to address the PM 10 needs for Nogales and Paul Spur/Douglas areas over the next few... certain columns and rows and thereby causes a mismatch between concentrations and the corresponding years...

  11. SEDIMENT DATA - ST. PAUL WATERWAY - TACOMA, WA - 1996 MONITORING DATA

    EPA Science Inventory

    Benthic Infauna Monitoring Data Files are Excel-format spreadsheet files which contain data presented in the St. Paul Waterway Area Remedial Action and Habitat Restoration Project, 1996 Monitoring Report. The files can be viewed directly or readily downlo aded and read into most ...

  12. Historical review: another 50th anniversary--new periodicities in coiled coils.

    PubMed

    Gruber, Markus; Lupas, Andrei N

    2003-12-01

    In 1953, Francis Crick and Linus Pauling both proposed models of supercoiled alpha helices ('coiled coils') for the structure of keratin. These were the first attempts at modelling the tertiary structure of a protein. Crick emphasized the packing mode of the side-chains ('knobs-into-holes'), which required a periodicity of seven residues over two helical turns (7/2) and a supercoil in the opposite sense of the constituent helices. By contrast, Pauling envisaged a broader set of periodicities (4/1, 7/2, 18/5, 15/4, 11/3) and supercoils of both senses. Crick's model became canonical and the 'heptad repeat' essentially synonymous with coiled coils, but 50 years later new crystal structures and protein sequences show that the less common periodicities envisaged by Pauling also occur in coiled coils, adding a variant packing mode ('knobs-to-knobs') to the standard model. Pauling's laboratory notebooks suggest that he searched unsuccessfully for this packing mode in 1953.

  13. Linus Pauling's "molecular diseases": between history and memory.

    PubMed

    Strasser, Bruno J

    2002-08-30

    In 1949, Linus Pauling and his collaborators published a study in the journal Science entitled "Sickle Cell Anemia, a Molecular Disease." In this now classic study, they showed that hemoglobin from patients suffering from sickle cell anemia has a different electrical charge than hemoglobin from healthy individuals. This result demonstrated for the first time that an abnormal protein could be causally linked to a disease, and that genes determined the structure of proteins. This report made headline news and had a powerful impact on both the biomedical community and the general public. Fifty years later, this study is discussed in almost every medical and biological textbook and has became a favorite example in editorials to illustrate the progress of biomedical research. This article explores the history of Pauling's sickle cell anemia and its subsequent integration in different collective memories, up to the present day. It also discusses the function of the collective memories of Pauling's discovery for contemporary biomedical research. Copyright 2002 Wiley-Liss, Inc.

  14. Are we hammering square pegs into round holes? An investigation of the meta-analyses of reading research with students who are d/Deaf or hard of hearing and students who are hearing.

    PubMed

    Wang, Ye; Williams, Cheri

    2014-01-01

    In a qualitative meta-analysis, the researchers systematically reviewed qualitative and quantitative meta-analyses on reading research with PK-12 students published after the 2000 National Reading Panel (NRP) report. Eleven qualitative and 39 quantitative meta-analyses were reviewed examining reading research with typically developing hearing students, special education hearing students (including English Language Learners), and d/Deaf or hard of hearing (d/Dhh) students. Generally, the meta-analysis yielded findings similar to and corroborative of the NRP's. Contradictory results (e.g., regarding the role of rhyme awareness in reading outcomes) most often resulted from differing definitions of interventions and their measurements. The analysis provided evidence of several instructional approaches that support reading development. On the basis of the qualitative similarity hypothesis (Paul, 2010, 2012; Paul & Lee, 2010; Paul & Wang, 2012; Paul, Wang, & Williams, 2013), the researchers argue that these instructional strategies also should effectively support d/Dhh children's reading development.

  15. Physics and our View of the World

    NASA Astrophysics Data System (ADS)

    Hilgevoord, Jan

    1994-11-01

    Foreword; 1. Introduction JAN HILGEVOORD; 2. Questioning the answers GERARD T. HOOFT; 3. Theories of everything JOHN BARROW; 4. The scientific view of the world DENNIS DIEKS; 5. Enlarging the world ERNAN McMULLIN; 6. The world of empiricism BAS VAN FRAASSEN; 7. Has the scientific view of the world a special status compared with other views? PAUL FEYERABEND; 8. Quantum theory and our view of the world PAUL FEYERABEND; 9. Interpretation of science - science as interpretation BAS VAN FRAASSEN; 10. Problems in debates about physics and religion WILLEM DREES; 11. The mind of God PAUL DAVIES; 12. The sources of models for God: metaphysics or metaphor? MARY HESSE; 13. Discussion.

  16. 49 CFR Appendix B to Part 604 - Reasons for Removal

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... honest mistake. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn... performing it. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn., 1968... force. In addition, no other policy of insurance has taken its place. Black's Law Dictionary, Revised...

  17. 49 CFR Appendix B to Part 604 - Reasons for Removal

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... honest mistake. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn... performing it. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn., 1968... force. In addition, no other policy of insurance has taken its place. Black's Law Dictionary, Revised...

  18. 49 CFR Appendix B to Part 604 - Reasons for Removal

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... honest mistake. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn... performing it. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn., 1968... force. In addition, no other policy of insurance has taken its place. Black's Law Dictionary, Revised...

  19. Passings to note: Paul Michael Packman, MD; S. Charles Schulz, MD.

    PubMed

    Black, Donald W

    2018-02-01

    One of the keys to the success of Annals of Clinical Psychiatry has always been the tireless efforts of our dedicated Editorial Board. We recently lost 2 longtime Editorial Board members, Drs. Paul Michael Packman and S. Charles Schulz. Both will be greatly missed.

  20. Classical Sax: Conversation with Paul Brodie.

    ERIC Educational Resources Information Center

    Row, David W.

    1984-01-01

    Paul Brodie, the most recorded concert saxophonist in the history of the instrument, talks about a number of topics, including his career, differences among saxophonists, mixing styles of playing, the effectiveness of music schools, and whether it is necessary to understand the structure of the piece being played. (RM)

  1. The Carbon New Age

    DTIC Science & Technology

    2010-03-01

    these allotropes show that they all have the same basic motif, namely, the benzene ring. Linus Pauling was one the first scientists to understand the...nature of these allotropes and in his 1950’s masterpiece “The Nature of the Chemical Bond”, Pauling describes graphite (the only allotrope that was

  2. Deputy to the Commanding General

    DTIC Science & Technology

    2012-10-18

    Kneller "The best way to have a good idea is to have a lot of ideas." — Dr. Linus Pauling "To raise new questions, new possibilities, to regard old...Development & Integration Directorate (CDID) Capability Portfolio Overview COL Courtney W. Paul 06 June 2012 MSCoE CDID Organization

  3. Sixteen Textbook Authors Respond.

    ERIC Educational Resources Information Center

    Hewitt, John P.; And Others

    1988-01-01

    The articles on textbook publication written by Sheryl Fullerton and Franklin C. Graham were responded to by: John Hewitt, Henry Tischler, George Ritzer, Paul Baker, Erich Goode, D. Stanley Eitzen, Jon Shepard, Richard Schaefer, Caroline Persell, Beth Hess, Paul Zopf, Jr., Jeanne Ballantine, Duane Monette, Mary Ann Lamanna, John Macionis, and…

  4. Center for Transportation Studies 24th annual transportation research conference, May 22-23, 2013, Saint Paul, Minnesota.

    DOT National Transportation Integrated Search

    2013-05-01

    The University of Minnesotas Center for Transportation : Studies is pleased to present its 24th Annual Transportation : Research Conference, May 22-23, 2013. The conference will : be held at the Saint Paul RiverCentre, 175 West Kellogg : Boulevard...

  5. A Response to Paul Stapleton's "Critiquing Research Methodology"

    ERIC Educational Resources Information Center

    Ross, Steven J.

    2006-01-01

    Paul Stapleton's (2006) critique of quantitative research brings to the surface some common interpretive problems arising when experimental and quasi-experimental research designs are compared. While Stapleton may be correct in pointing out the superiority of experimental research designs because they best eliminate the influence of extraneous…

  6. Abiotic Remediation of Nitro-Aromatic Groundwater Contaminants by Zero-Valent Iron

    DTIC Science & Technology

    1994-03-18

    Paul G. Tratnyek 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Department of Environmental Science N/A...REMEDIATION OF NITRO-AROMATIC GROUNDWATER CONTAMINANTS BY ZERO-VALENT IRON Abinash Agrmwal and Paul G. Tratnyek Department of Environmental Science and

  7. 49 CFR Appendix B to Part 604 - Reasons for Removal

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... honest mistake. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn... performing it. Black's Law Dictionary, Revised Fourth Edition, West Publishing Company, St. Paul, Minn., 1968... force. In addition, no other policy of insurance has taken its place. Black's Law Dictionary, Revised...

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Kun; Bannister, Mark E.; Meyer, Fred W.

    Here, in a magnetic fusion energy (MFE) device, the plasma-facing materials (PFMs) will be subjected to tremendous fluxes of ions, heat, and neutrons. The response of PFMs to the fusion environment is still not well defined. Tungsten metal is the present candidate of choice for PFM applications such as the divertor in ITER. However, tungsten's microstructure will evolve in service, possibly to include recrystallization. How tungsten's response to plasma exposure evolves with changes in microstructure is presently unknown. In this work, we have exposed hot-worked and recrystallized tungsten to an 80 eV helium ion beam at a temperature of 900more » °C to fluences of 2 × 10 23 or 20 × 10 23 He/m 2. This resulted in a faceted surface structure at the lower fluence or short but well-developed nanofuzz structure at the higher fluence. There was little difference in the hot-rolled or recrystallized material's near-surface (≤50 nm) bubbles at either fluence. At higher fluence and deeper depth, the bubble populations of the hot-rolled and recrystallized were different, the recrystallized being larger and deeper. This may explain previous high-fluence results showing pronounced differences in recrystallized material. The deeper penetration in recrystallized material also implies that grain boundaries are traps, rather than high-diffusivity paths.« less

  9. A modular assembling platform for manufacturing of microsystems by optical tweezers

    NASA Astrophysics Data System (ADS)

    Ksouri, Sarah Isabelle; Aumann, Andreas; Ghadiri, Reza; Prüfer, Michael; Baer, Sebastian; Ostendorf, Andreas

    2013-09-01

    Due to the increased complexity in terms of materials and geometries for microsystems new assembling techniques are required. Assembling techniques from the semiconductor industry are often very specific and cannot fulfill all specifications in more complex microsystems. Therefore, holographic optical tweezers are applied to manipulate structures in micrometer range with highest flexibility and precision. As is well known non-spherical assemblies can be trapped and controlled by laser light and assembled with an additional light modulator application, where the incident laser beam is rearranged into flexible light patterns in order to generate multiple spots. The complementary building blocks are generated by a two-photon-polymerization process. The possibilities of manufacturing arbitrary microstructures and the potential of optical tweezers lead to the idea of combining manufacturing techniques with manipulation processes to "microrobotic" processes. This work presents the manipulation of generated complex microstructures with optical tools as well as a storage solution for 2PP assemblies. A sample holder has been developed for the manual feeding of 2PP building blocks. Furthermore, a modular assembling platform has been constructed for an `all-in-one' 2PP manufacturing process as a dedicated storage system. The long-term objective is the automation process of feeding and storage of several different 2PP micro-assemblies to realize an automated assembly process.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Jiajun; Wang, Liguang; Eng, Christopher

    We present that irreversible electrochemical behavior and large voltage hysteresis are commonly observed in battery materials, in particular for materials reacting through conversion reaction, resulting in undesirable round-trip energy loss and low coulombic efficiency. Seeking solutions to these challenges relies on the understanding of the underlying mechanism and physical origins. Here, this study combines in operando 2D transmission X-ray microscopy with X-ray absorption near edge structure, 3D tomography, and galvanostatic intermittent titration techniques to uncover the conversion reaction in sodium–metal sulfide batteries, a promising high-energy battery system. This study shows a high irreversible electrochemistry process predominately occurs at first cycle,more » which can be largely linked to Na ion trapping during the first desodiation process and large interfacial ion mobility resistance. Subsequently, phase transformation evolution and electrochemical reaction show good reversibility at multiple discharge/charge cycles due to materials' microstructural change and equilibrium. The origin of large hysteresis between discharge and charge is investigated and it can be attributed to multiple factors including ion mobility resistance at the two-phase interface, intrinsic slow sodium ion diffusion kinetics, and irreversibility as well as ohmic voltage drop and overpotential. In conclusion, this study expects that such understandings will help pave the way for engineering design and optimization of materials microstructure for future-generation batteries.« less

  11. In-situ TEM observation of the response of ultrafine- and nanocrystalline-grained tungsten to extreme irradiation environments

    PubMed Central

    El-Atwani, O.; Hinks, J. A.; Greaves, G.; Gonderman, S.; Qiu, T.; Efe, M.; Allain, J. P.

    2014-01-01

    The accumulation of defects, and in particular He bubbles, can have significant implications for the performance of materials exposed to the plasma in magnetic-confinement nuclear fusion reactors. Some of the most promising candidates for deployment into such environments are nanocrystalline materials as the engineering of grain boundary density offers the possibility of tailoring their radiation resistance properties. In order to investigate the microstructural evolution of ultrafine- and nanocrystalline-grained tungsten under conditions similar to those in a reactor, a transmission electron microscopy study with in situ 2 keV He+ ion irradiation at 950°C has been completed. A dynamic and complex evolution in the microstructure was observed including the formation of defect clusters, dislocations and bubbles. Nanocrystalline grains with dimensions less than around 60 nm demonstrated lower bubble density and greater bubble size than larger nanocrystalline (60–100 nm) and ultrafine (100–500 nm) grains. In grains over 100 nm, uniform distributions of bubbles and defects were formed. At higher fluences, large faceted bubbles were observed on the grain boundaries, especially on those of nanocrystalline grains, indicating the important role grain boundaries can play in trapping He and thus in giving rise to the enhanced radiation tolerance of nanocrystalline materials. PMID:24796578

  12. Paul Langerhans: a prilgrim "traveling" from functional histology to marine biology.

    PubMed

    Raica, Marius; Cimpean, Anca Maria

    2017-06-01

    The nineteenth century was the time of a real revolution in science and medicine. A lot of seminal discoveries in medicine and biology were done in this time, and many of them were coincident with the introduction of the compound microscope by Hermann van Deijl and the standard histological technique by Paul Ehrlich. The main tissue types and individual cells were characterized and originally classified more than hundred years ago, although less attention was paid to their basic functions. This was mainly due to the modality of tissue specimen processing that allowed particularly detailed descriptive studies. Even so, we can notice some attempts to correlate the structure with the function. The German scientist Paul Langerhans, well-known for the discovery of Langerhans islets of the pancreas and Langerhans cells from the epidermis, tried to change the conventional fate of morphological studies introducing in his works functional hypothesis based on traditional microscopic observations even from the beginning of his scientific career. Paul Langerhans was a complex personality of the second half of the nineteenth century, not only in medicine, but also in other fields of biology. In the present review, presented is the life and research activity of Paul Langerhans, not only because of the importance of his discoveries, but also for perspectives that were opened by these findings in unexpected fields of medicine and biology.

  13. The snowmaker: nature identical snow production in the laboratory

    NASA Astrophysics Data System (ADS)

    Schleef, S.; Jaggi, M.; Loewe, H.; Schneebeli, M.

    2013-12-01

    Using natural snow for laboratory experiments can be tricky due to shortage of winter periods and snowfall, difficulties of sample casting and transport, and the great variability of natural snow due to the varying conditions of crystal growth in the clouds. This hinders repeatable laboratory experiments with reproducible specimen and microstructural characteristics. To minimize experimental uncertainties we designed an improved machine called snowmaker, which enables us to produce nature-identical snow in a cold laboratory under well defined conditions. The snowmaker is based on well-known principles: warm humid air from a heated water basin is advected into a cold nucleation chamber where the vapor resublimates on stretched Nylon wires. Crystals are automatically harvested by a motor driven brush rack and collected in a box, thereby several kilograms of snow can be produced per day with minimum maintenance. The excess vapor is collected in a moisture trap to avoid frost in the laboratory. The entire construction is designed as a rolling, modular assembly system which can easily carried out of the laboratory for defrosting. In addition to previous attempts we focus on the reproducibility of the samples and the comparison to natural snow down to the microscale. We show that the settings of water temperature and cold laboratory temperature facilitates the production of different crystal shapes like dendrites and needles in a reproducible way. Besides photography, we analyzed the microstructure of snowmaker crystals in aggregated specimen by X-ray microtomography. Depending on the settings we can create reproducible samples with density of 50-170 kg/m3 and specific surface areas of 50-80 mm-1. We briefly touch similarities between artificial and natural snow samples with respect to crystal habit, microstructural parameters and short-time metamorphism.

  14. Microstructure and conductance-slope of InAs/GaSb tunnel diodes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Iutzi, Ryan M., E-mail: iutzi@mit.edu; Fitzgerald, Eugene A.

    2014-06-21

    InAs/GaSb and similar materials systems have generated great interest as a heterojunction for tunnel field effect transistors (TFETs) due to favorable band alignment. However, little is currently understood about how such TFETs are affected by materials defects and nonidealities. We present measurements of the conductance slope for various InAs/GaSb heterojunctions via two-terminal electrical measurements, which removes three-terminal parasitics and enables direct study on the effect of microstructure on tunnelling. Using this, we can predict how subthreshold swings in TFETs can depend on microstructure. We also demonstrate growth and electrical characterization for structures grown by metalorganic chemical vapor deposition (MOCVD)—a generallymore » more scalable process compared with molecular beam epitaxy (MBE). We determine that misfit dislocations and point defects near the interface can lead to energy states in the band-gap and local band bending that result in trap-assisted leakage routes and nonuniform band alignment across the junction area that lower the steepness of the conductance slope. Despite the small lattice mismatch, misfit dislocations still form in InAs on GaSb due to relaxation as a result of large strain from intermixed compositions. This can be circumvented by growing GaSb on InAs, straining the GaSb underlayer, or lowering the InAs growth temperature in the region of the interface. The conductance slope can also be improved by annealing the samples at higher temperatures, which we believe acts to annihilate point defects and average out major fluctuations in band alignment across the interface. Using a combination of these techniques, we can greatly improve the steepness of the conductance slope which could result in steeper subthreshold swings in TFETs in the future.« less

  15. Paul Vallas for Sale

    ERIC Educational Resources Information Center

    Dessoff, Alan

    2012-01-01

    Veteran Superintendent Paul Vallas, who has led turnaround efforts in major urban districts in Chicago, Philadelphia and New Orleans, has started a new venture that he expects will broaden his reach and extend the reform movement. The Vallas Group, headed by Vallas, now interim superintendent of the Bridgeport (Connecticut) Public Schools, is…

  16. 70. Photocopy of photograph (original print in the Minnesota Historical ...

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

    70. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, 1904. #18613g. Photographer: Albert Munson) VIEW TO WEST, SHOWING FALSEWORK USED IN RECONTRUCTING THE HIGH BRIDGE, 1904. - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  17. Paul Zindel: Flirting with the Bizarre.

    ERIC Educational Resources Information Center

    Winarski, Diana L.

    1994-01-01

    Profiles Paul Zindel, the best-selling author of childrens' and adolescents' novels who combines hyperbole and pathos in such works as "The Pigman;""My Darling, My Hamburger;" and "The Pigman and Me." Zindel is also the author of the play "The Effect of Gamma Rays on Man-in-the-Moon Marigolds." (MDM)

  18. Nature, Human Nature, and Solutions to Problems.

    ERIC Educational Resources Information Center

    Pedrini, D. T.; Pedrini, B. C.

    This paper promotes an undergraduate course that would discuss the great ideas of Plato, St. Paul, Karl Marx, Sigmund Freud, Jean Paul Sartre, B. F. Skinner, and Konrad Lorenz. This course would help students understand human values and behaviors while focusing on historical, world, and national problems. Tentative solutions would then be…

  19. A Report on Administrative Compensation Planning for St. Paul Public School Personnel.

    ERIC Educational Resources Information Center

    Hooker, Clifford P.; Mueller, Van D.

    This report describes and analyzes various devices and techniques that may be utilized in planning local school administrative compensation. The document outlines broad overall goals for compensation planning, describes and evaluates the application of a compensation plan in the St. Paul schools, and proposes alternative strategies for…

  20. Speaking Personally--With Paul Avon

    ERIC Educational Resources Information Center

    Martin, D'Arcy

    2012-01-01

    This article presents an interview with Paul Avon, the former executive director of the Canadian Virtual College Consortium. Avon has spent over fifteen years in the distance learning (DL) field managing the production and delivery of online learning at TVOntario, Humber College, the Sri Lankan National Online Distance Education Service, and the…

  1. Guidelines for Software Engineering Education Version 1.0

    DTIC Science & Technology

    1999-11-01

    Turbo Pascal and Software Design. Sudbury, Massachusetts: Jones and Bartlett, 1997. " Deitel, Harvey M. & Deitel, Paul J. C++: How to Program . Upper...Saddle River, New Jersey: Prentice-Hall, 1997. " Deitel, Harvey M. & Deitel, Paul J. Java: How to Program . Upper Saddle River, New Jersey: Prentice-Hall

  2. Molecular Orbital (Hückel) Theory and Linus Pauling: A Historical Perspective

    NASA Astrophysics Data System (ADS)

    Sharma, Brahama D.

    1996-08-01

    This short article offers evidence contrary to the belief that Linus Pauling was somehow opposed to Hückel-type calculations and that he therefore provided little or no support to the school of scientists in the '60s who were engaged in these semiempirical calculations.

  3. Linus Pauling Memorial Lectures

    Science.gov Websites

    Institute for Science, Engineering and Public Policy Home About The Institute Format/Policy Pauling Memorial Lectures Science, Engineering and Public Policy 2017-2018 Sabbatical Year Taking a Year Physics to the New Philosophy Terry Bristol Institute for Science, Engineering and Public Policy 7:00pm

  4. Improving Success in Developmental Mathematics: An Interview with Paul Nolting

    ERIC Educational Resources Information Center

    Boylan, Hunter R.

    2011-01-01

    This article presents an interview with Dr. Paul Nolting, a national expert in assessing individual math learning problems, developing effective student learning strategies, and assessing institutional variables that affect math success. Since his dissertation in 1986 on improving math success with study skills Dr. Nolting has consulted with over…

  5. 13. Photocopy of 1875 stereograph. Original in Paul A. Kohl's ...

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

    13. Photocopy of 1875 stereograph. Original in Paul A. Kohl's office, Tower Grove, Missouri Botanical Garden. HENRY SHAW AND TWO GUESTS IN HIS LANDAU DRAWN BY A MATCHED PAIR IN FRONT OF THE EAST GATE - Tower Grove Park, East Gate Entrance, 4255 Arsenal Street, Saint Louis, Independent City, MO

  6. SeaBASS 2012: A Marine BioAcoustics Summer School

    DTIC Science & Technology

    2012-09-30

    accepted from six different countries (USA & Puerto Rico, Italy, United Kingdom, Greece, Canada, and Austria). Advertising for SeaBASS was published...there was so much good and varied information in all the lectures, I would have to give it to Paul for his storytelling . • Paul Nachtigall’s lecture

  7. Paul Ricoeur, Memory, and the Historical Gaze: Implications for Education Histories

    ERIC Educational Resources Information Center

    Colby, Sherri Rae

    2012-01-01

    In this article, the author shares the potential applications of Paul Ricoeur's philosophies of history, memory, and narrative to the interpretation of educational histories, and those histories' life spans: moving cyclically from early conception, to evidentiary construction, to published dissemination; and ultimately to death or immortality. Her…

  8. 76 FR 38621 - New England Fishery Management Council; Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... Street, Mill 2, Newburyport, MA 01950. FOR FURTHER INFORMATION CONTACT: Paul J. Howard, Executive... Monkfish Advisory Panel (AP) will meet to develop a detailed problem statement based on the list of issues... other auxiliary aids should be directed to Paul J. Howard, Executive Director, at (978) 465- 0492, at...

  9. 77 FR 28421 - Supplemental Draft Environmental Impact Statement for the Central Corridor Light Rail Transit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-14

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Supplemental Draft Environmental Impact Statement for the Central Corridor Light Rail Transit Project, Minneapolis and Saint Paul, MN... Minneapolis and Saint Paul downtown areas as well as the University of Minnesota and the State Capitol complex...

  10. 78 FR 21141 - Changes in Flood Hazard Determinations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-09

    ... Center at www.msc.fema.gov . FOR FURTHER INFORMATION CONTACT: Luis Rodriguez, Chief, Engineering...). County Judge, Paul North Pecos- La Elizondo Tower, 101 Trinidad Street, West Nueva Street, Suite 420, San..., Bexar Works Department, 233 06-2935P). County Judge, Paul North Pecos- La Elizondo Tower, 101 Trinidad...

  11. The Canadian Forces Use of Private Security in Afghanistan: A Consequence of National Decisions

    DTIC Science & Technology

    2013-12-10

    Swiss Peace (November 2007): 10-12. 5Paul Krugman, Robin Wells, and Martha Olney, Essentials of Economics (Macmillan, 2007), 56-84. 3...Paul, Robin Wells, and Martha Olney. Essentials of Economics . Macmillan, 2007. Kuhn, Thomas, S. The Structure of Scientific Revolutions. Chicago

  12. Career Counseling of College Students: An Empirical Guide to Strategies That Work.

    ERIC Educational Resources Information Center

    Luzzo, Darrell Anthony, Ed.

    This book contains 17 papers devoted to the counseling of college students. The following papers are included: "Introduction" (Darrell Anthony Luzzo); "Established Career Theories" (Paul J. Hartung, Spencer G. Niles); "Emerging Career Theories" (Spencer G. Niles, Paul J. Hartung); "Emotional-Social Issues in the…

  13. Excerpts from Vatican's "Veritatis Splendor," Pope John Paul II's Views of Moral Truth.

    ERIC Educational Resources Information Center

    Chronicle of Higher Education, 1993

    1993-01-01

    Excerpts are presented from a recent papal encyclical that sets forth John Paul II's views on timeless moral truths and on dissent from them within the Roman Catholic Church. The responsibility of bishops to monitor Catholic institutions, including educational institutions, is noted. (MSE)

  14. Beyond Bombs, Bullets and Planes: Developing Airmen-Statements for the 21st Century

    DTIC Science & Technology

    2009-12-11

    credibility, trust and respect • Resolving conflict Source: Chaitra M. Hardison, Carra S. Sims, Farahana Ali, Andres Villamizar, Ben Mundell , and Paul......Categories Source: Chaitra M. Hardison, Carra S. Sims, Farahana Ali, Andres Villamizar, Ben Mundell , and Paul Howe, Cross-Cultural Skills for Deployed

  15. Paul Winter, Sun Singer...He Talks about Outdoor Education.

    ERIC Educational Resources Information Center

    Breslav, Marc

    1984-01-01

    Interviews Paul Winter, well-known musical emissary for the Earth and its wildlife among the environmental community. Incorporating voices of wolves, whales, and other creatures as accompanists to an uncategorizable blend of symphonic, jazz, African and Latin musical traditions, Winter's sound involves listeners in a guided experience of…

  16. A Schedule-Based Approach for Flow-Control in Data Communication Networks

    DTIC Science & Technology

    1986-01-01

    Tally Altes, Erdal Arikan , Carey Bunks, Isidro Castineyra, Julio Escobar, Eli Gafni, Ellen Hahne, Dan Helman, Patrick Hosein, Joe Hui, Atul Khanna...Tiedemann, Kevin Tsai, Paul Tseng, Paul Wiley, and Albert Wong. I have especially enjoyed many discussions with Ellen Hahne, Erdal Arikan , Jean Regnier

  17. The Role of the National Guard in Homeland Security

    DTIC Science & Technology

    2007-05-01

    Fulcrum Publishing, 1996), 19. 22Ibid., 20. 23Thomas Andrew Bailey and Paul B. Ryan, The Lusitania Disaster: An Episode in Modern Warfare and...Bailey, Thomas Andrew, and Paul B. Ryan. The Lusitania Disaster: An Episode in Modern Warfare and Diplomacy. New York, NY: Free Press, 1975. Ball

  18. Philosophy of Education Today

    ERIC Educational Resources Information Center

    Chambliss, J. J.

    2009-01-01

    In this review essay J.J. Chambliss assesses the current state of the field of philosophy of education through analysis of four recent edited compilations: Randall Curren's "A Companion to Philosophy of Education"; Nigel Blake, Paul Smeyers, Richard Smith, and Paul Standish's "The Blackwell Guide to Philosophy of Education"; Wilfred Carr's "The…

  19. Revolution and Education in Late Nineteenth Century France: The Early Career of Paul Robin.

    ERIC Educational Resources Information Center

    Mclaren, Angus

    1981-01-01

    Discusses the importance of the work of radical educator Paul Robin and the socio-political environment in nineteenth century France which prompted it. Robin advocated free, secular, public education for the working classes which stressed spontaneity, practicality, individualized instruction, and sexual equality. (AM)

  20. Combinatorial Relationships Learned by a Language-Trained Sea Lion

    DTIC Science & Technology

    1992-01-01

    assistants. We thank Paul Losiewicz, Paul Nachtigall, and Herb Roitblat for reviewing a previous draft of this paper. LITERATURE CITED Chomsky, N., 1959, A...34Language and Communication: Comparative Perspectives," H. Roitblat , L. Herman, and P. Nachtigall, eds., L. Erlbaum, Hillsdale, NJ. Schusterman, R. J., and

  1. A novel pre-sintering technique for the growth of Y-Ba-Cu-O superconducting single grains from raw metal oxides

    NASA Astrophysics Data System (ADS)

    Li, Jiawei; Shi, Yun-Hua; Dennis, Anthony R.; Namburi, Devendra Kumar; Durrell, John H.; Yang, Wanmin; Cardwell, David A.

    2017-09-01

    Most established top seeded melt growth (TSMG) processes of bulk, single grain Y-Ba-Cu-O (YBCO) superconductors are performed using a mixture of pre-reacted precursor powders. Here we report the successful growth of large, single grain YBCO samples by TSMG with good superconducting properties from a simple precursor composition consisting of a sintered mixture of the raw oxides. The elimination of the requirement to synthesize precursor powders in a separate process prior to melt processing has the potential to reduce significantly the cost of bulk superconductors, which is essential for their commercial exploitation. The growth morphology, microstructure, trapped magnetic field and critical current density, J c, at different positions within the sample and maximum levitation force of the YBCO single grains fabricated by this process are reported. Measurements of the superconducting properties show that the trapped filed can reach 0.45 T and that a zero field J c of 2.5 × 104 A cm-2 can be achieved in these samples. These values are comparable to those observed in samples fabricated using pre-reacted, high purity commercial oxide precursor powders. The experimental results are discussed and the possibility of further improving the melt process using raw oxides is outlined.

  2. Effects of high optical injection levels in polycrystalline Si wafers on carrier transport

    NASA Astrophysics Data System (ADS)

    Steele, Doneisha; Semichaevsky, Andrey

    High levels of carrier injection in polycrystalline Si may arise, for example, in solar cells under concentrated sunlight. Mechanisms for non-radiative carrier recombination include trap-mediated SRH and higher-order processes, e.g., Auger recombination. In this paper we present our experimental results for intensity-dependent carrier lifetimes and conduction currents in polycrystalline Si wafers illuminated with pulses of up to 50 Sun intensity. We also use a computational model for carrier transport that includes both SRH and Auger recombination mechanisms, in order to explain our experiments. The model allows quantifying recombination rate dependence on carrier concentration. Our goal is to relate the recombination rates to Si microstructure and defect densities that are revealed by IR PL images. We acknowledge the NSF support through Grant 1505377.

  3. Magnetic properties of Y3+ doped Bi4-xTi2FeO12 aurivillius phase ceramics

    NASA Astrophysics Data System (ADS)

    Tirupathi, Patri; Reddy, H. Satish Kumar; Babu, P. D.

    2018-05-01

    In the present paper reports a comprehensive investigation of structural, microstructural and magnetic phase transition in Y3+ doped BITF Aurivillius phase compounds. The study of surface morphology by scanning electron microscope reveals the growth of plate-like grains and further the grain size increase with increasing Y3+ composition. Low temperature magnetic studies reveals enhanced magnetic property with doping of Y3+ in BITF. It was explained by considering exchange interaction between the neighboring Fe+3 ions via electron trapped electrons at oxygen vacancies. Temperature dependent dc-magnetic studies exhibit a magnetic transitions TC = 750 K for x=0.0 TC ˜ 674 K for x=1.0 & TC ˜ 645 K for x=1.50 ceramics respectively in high temperature magnetization studies

  4. Computational prediction of Mg-isotope fractionation between aqueous [Mg(OH2)6]2+ and brucite

    NASA Astrophysics Data System (ADS)

    Colla, Christopher A.; Casey, William H.; Ohlin, C. André

    2018-04-01

    The fractionation factor in the magnesium-isotope fractionation between aqueous solutions of magnesium and brucite changes sign with increasing temperature, as uncovered by recent experiments. To understand this behavior, the Reduced Partition Function Ratios and isotopic fractionation factors (Δ26/24Mgbrucite-Mg(aq)) are calculated using molecular models of aqueous [Mg(OH2)6]2+ and the mineral brucite at increasing levels of density functional theory. The calculations were carried out on the [Mg(OH2)6]2+·12H2O cluster, along with different Pauling-bond-strength-conserving models of the mineral lattice of brucite. Three conclusions were reached: (i) all levels of theory overestimate bond distances in the aqua ion complex relative to Tutton's salts; (ii) the calculations predict that brucite at 298.15 K is always enriched in the heavy isotope, in contrast with experimental observations; (iii) the temperature dependencies of Wimpenny et al. (2014) and Li et al. (2014) could only be achieved by fixing the bond distances in the [Mg(OH2)6]2+·12H2O cluster to values close to those observed in crystals that trap the hydrated ion.

  5. Case Report on the Illness of Paul Klee (1879–1940)

    PubMed Central

    Suter, Hans

    2014-01-01

    This article reports on the disease that afflicted Paul Klee, the famous artist. He died before the disease that killed him could be properly diagnosed. There was some conjecture afterwards that he may have suffered from scleroderma. The thorough and diligent research the author of this article has carried out over many years allows him to argue that Paul Klee was suffering from this autoimmune disease since 1935. With a degree of probability that borders on certainty, it seems that the artist suffered from ‘diffuse systemic sclerosis’, and it is from this, the most severe form of the rare autoimmune disease, that he died in 1940. PMID:24876831

  6. Enhanced positron trapping by Ag nanoclusters at low temperatures: A challenge of positron sensitivity to quantum dots

    NASA Astrophysics Data System (ADS)

    Zou, B.; Qi, N.; Liu, Z. W.; Chen, Z. Q.; Liu, H. Q.; Yi, D. Q.; Tang, Z.

    2017-03-01

    Microstructure evolution of three Al-Ag alloys with different Ag contents (1 wt. % Ag, 5 wt. % Ag, and 15 wt. % Ag) was studied by positron annihilation spectroscopy during the aging process. In situ measurements of the positron lifetime and Doppler broadening of annihilation radiation indicate the fast formation of Ag-rich clusters during natural aging of the alloys. The formation of Ag-rich clusters was further confirmed by coincidence Doppler broadening measurements. The Ag signal reflected by the Coincidence Doppler broadening spectrum increases with increasing Ag content and is further enhanced after subsequent artificial aging at 140 °C. This might be due to the increase in the size of Ag clusters. The temperature dependence of the Doppler broadening spectra between 10 K and 290 K was measured for the Al-Ag alloys after natural and artificial aging. Detrapping of positrons from Ag clusters with increasing temperature was observed for all the three Al-Ag alloys after natural aging and for the Al-1 wt. % Ag after artificial aging. This indicates that Ag clusters act as shallow positron trapping centers. The thermal detrapping of positrons becomes ambiguous with increasing Ag content in the alloy and is nearly invisible in the artificially aged Al-5 wt. % Ag and Al-15 wt. % Ag. The positron binding energy of the Ag cluster is roughly estimated to be about 18.8 meV and 50 meV in the Al-1 wt. % Ag sample after natural aging and artificial aging at 140 °C, respectively, which suggests that the confinement of positrons in the quantum-dot like state depends on the size or chemical composition of clusters. Theoretical calculations confirm positron trapping by Ag nanoclusters, and the confinement of positrons is enhanced with increasing Ag cluster size.

  7. Soy protein is beneficial but high-fat diet and voluntary running are detrimental to bone structure in mice.

    PubMed

    Yan, Lin; Graef, George L; Nielsen, Forrest H; Johnson, LuAnn K; Cao, Jay

    2015-06-01

    Physical activity and soy protein isolate (SPI) augmentation have been reported to be beneficial for bone health. We hypothesized that combining voluntary running and SPI intake would alleviate detrimental changes in bone induced by a high-fat diet. A 2 × 2 × 2 experiment was designed with diets containing 16% or 45% of energy as corn oil and 20% SPI or casein fed to sedentary or running male C57BL/6 mice for 14 weeks. Distal femurs were assessed for microstructural changes. The high-fat diet significantly decreased trabecular number (Tb.N) and bone mineral density (BMD) and increased trabecular separation (Tb.Sp). Soy protein instead of casein, regardless of fat content, in the diet significantly increased bone volume fraction, Tb.N, connectivity density, and BMD and decreased Tb.Sp. Voluntary running, regardless of fat content, significantly decreased bone volume fraction, Tb.N, connectivity density, and BMD and increased Tb.Sp. The high-fat diet significantly decreased osteocalcin and increased tartrate-resistant acid phosphatase 5b (TRAP 5b) concentrations in plasma. Plasma concentrations of osteocalcin were increased by both SPI and running. Running alleviated the increase in TRAP 5b induced by the high-fat diet. These findings demonstrate that a high-fat diet is deleterious, and SPI is beneficial to trabecular bone properties. The deleterious effect of voluntary running on trabecular structural characteristics indicates that there may be a maximal threshold of running beyond which beneficial effects cease and detrimental effects occur. Increases in plasma osteocalcin and decreases in plasma TRAP 5b in running mice suggest that a compensatory response occurs to counteract the detrimental effects of excessive running. Published by Elsevier Inc.

  8. Effects of interleukin-7/interleukin-7 receptor on RANKL-mediated osteoclast differentiation and ovariectomy-induced bone loss by regulating c-Fos/c-Jun pathway.

    PubMed

    Zhao, Ji-Jun; Wu, Zhao-Feng; Yu, Ying-Hao; Wang, Ling; Cheng, Li

    2018-09-01

    To explore the effects of IL-7/IL-7R on the RANKL-mediated osteoclast differentiation in vitro and OVX-induced bone loss in vivo. BMMs and RAW264.7 were transfected with IL-7, IL-7R siRNA, c-Fos siRNA, and c-jun siRNA and later stimulated by RANKL. TRAP and toluidine blue staining were used to observe osteoclast formation and bone resorption, respectively. HE and TRAP staining were used to detect trabecular bone microstructure and osteoclasts of mice, respectively. qRT-PCR and Western blot analysis were used to examine expression. IL-7 unregulated the expression of CTSK, NFATc1, MMP9, and the phosphorylation of p38 and Akt by activating the c-Fos/c-Jun pathway, which increased osteoclast numbers and bone resorption in RANKL-stimulated macrophages. While IL-7R siRNA and c-Fos siRNA decreased the expression, as well as and the phosphorylation of p38 and Akt.IL-7 decreased the BMD and OPG expression in OVX-induced mice and increased the TRAP positive cells, the mRNA expression of c-fos, c-jun, and RANKL, which was contradictory to IL-7R siRNA, and c-Fos siRNA. Furthermore, IL-7R siRNA and c-Fos siRNA caused thicker trabeculae, increased trabecular number, and decreased osteolysis in OVX mice. IL-7/IL-7R can promote RANKL-mediated osteoclast formation and bone resorption by activating the c-Fos/c-Jun pathway, as well as inducing bone loss in OVX mice. © 2018 Wiley Periodicals, Inc.

  9. Publishing and Intergenerational Learning for the Future of Philosophy in Education: An Interview with Paul Smeyers

    ERIC Educational Resources Information Center

    Forster, Daniella J.

    2017-01-01

    Amongst a remarkable publishing career, Paul Smeyers, editor of the journal "Ethics and Education," has written extensively on the situation afflicting philosophy of education. A recently published editor's invited symposium in "Studies in Philosophy and Education" (Smeyers, De Ruyter, Waghid, & Strand, 2014) put forward…

  10. Hermann Paul and General Linguistic Theory

    ERIC Educational Resources Information Center

    Koerner, E. F. K.

    2008-01-01

    In most history of linguistics textbooks available until today Hermann Paul and his "Principles of Historical Linguistics," first published in 1880 and still available in reprints of the fifth edition of 1920, if given any attention at all, is cited for a statement he included in the second edition of 1886 in response to a review that…

  11. 34. Photographic copy of historic construction drawing, ink on linen, ...

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

    34. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: Plan of masonry. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  12. In Conversation with Paul Burstow

    ERIC Educational Resources Information Center

    Holman, Andrew

    2013-01-01

    Paul Burstow, a former minister for social care, was once charged with finding savings in care services. He completed his last two years, cut the Valuing People Now programme early, and returned to the back benches. He did, however, draft a Care and Support Bill and has subsequently used this experience to chair a joint Parliamentary Scrutiny…

  13. A Method for Predicting Manning Factors in Post Year 2000 Ships

    DTIC Science & Technology

    1975-12-01

    the automated condition. ij ;: Related to the problem of model validity is the consideration of the accuracy of the predictions. Linus Pauling ...described his use of the word "stochastic" in the April 1955 American Scientist. According to Pauling , the word is derived from a Greek stem which

  14. Tempus Pro Patient Monitoring System

    DTIC Science & Technology

    2015-04-03

    AFMSA SG5T, (AFMESA) Mr. John Ingram, AFMSA SG5T, AFMESA Mr. John Plaga , 711 HPW/HP Human Factors Engineering Mr. Paul Bailey, AMC SG/SGR Ms. Lynn...John Plaga , 711 HPW/HP Human Factors Engineering Mr. Paul Bailey, AMC SG/SGR Lt Col Cheryl Hale, AMC SG/SGK Mr. Graham Murphy, RDT Mr. Nigel

  15. Near-surface geophysical characterization of Holocene faults conducive to geothermal flow near Pyramid Lake, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dudley, Colton; Dorsey, Alison; Louie, John

    Colton Dudley, Alison Dorsey, Paul Opdyke, Dustin Naphan, Marlon Ramos, John Louie, Paul Schwering, and Satish Pullammanappallil, 2013, Near-surface geophysical characterization of Holocene faults conducive to geothermal flow near Pyramid Lake, Nevada: presented at Amer. Assoc. Petroleum Geologists, Pacific Section Annual Meeting, Monterey, Calif., April 19-25.

  16. Justice John Paul Stevens and the Erotic Boomerang.

    ERIC Educational Resources Information Center

    Lieberman, Marc

    Justice John Paul Stevens of the United States Supreme Court has ruled on obscenity cases in seven instances since his appointment. His rulings reveal that he regards obscenity as a nuisance rather than as a danger threatening to undermine the nation's morality, that he supports a nationwide standard to adjudicate obscenity cases, and that he…

  17. 1. GENERAL VIEW OF MAIN (SOUTH) FACADE OF CHURCH, LOOKING ...

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

    1. GENERAL VIEW OF MAIN (SOUTH) FACADE OF CHURCH, LOOKING NORTH (For a brief history of Boswell and a description of Sts. Peter and Paul Russian Orthodox Greek Catholic Church see TOWN OF BOSWELL, HAER PA-367) - Saints Peter & Paul Russian Orthodox Greek Catholic Church, Quemahoning Street, Boswell, Somerset County, PA

  18. Paul Piccone: Outside Academe

    ERIC Educational Resources Information Center

    Jacoby, Russell

    2008-01-01

    Today the academic world--open to Jews, women, and other previously excluded groups--has been completely revamped. Or has it? Despite the changes, is it possible the institution still promotes the mediocre and demotes the extraordinary? The life and work of Paul Piccone bear on this question--and others. Piccone, who died of cancer in 2004 at 64,…

  19. "Paul Revere's Ride": Awakening Abolitionists

    ERIC Educational Resources Information Center

    Lepore, Jill

    2011-01-01

    Henry Wadsworth Longfellow used to be both the best-known poet in the English-speaking world and the most beloved, adored by the learned and the lowly alike, read by everyone from Nathaniel Hawthorne and Abraham Lincoln to John Ruskin and Queen Victoria--and, just as avidly, by the queen's servants. "Paul Revere's Ride" is Longfellow's best-known…

  20. The Paul Petzoldt Trivia Quiz: His Philosophy and Teaching Methods.

    ERIC Educational Resources Information Center

    Wagstaff, Mark

    Paul Petzoldt, co-founder of the Wilderness Education Association (WEA), helped mold the profession of outdoor leadership as we know it today. After his death in 1999, numerous field journals, old speeches, and personal correspondence were salvaged in order to refresh, clarify, and preserve Petzoldt's philosophy and teaching methods. The…

  1. Finding a New Path to Learning

    ERIC Educational Resources Information Center

    Curriculum Review, 2006

    2006-01-01

    This article presents an interview with Paul Neff, a veteran teacher at Spokane, Washington's Lewis & Clark High. Paul Neff recently earned a $4,930 grant from the Toshiba America Foundation to purchase global-positioning systems and digital cameras for the Outdoor Living class he just took over two years ago. In an interview, Neff talks about…

  2. The Paul A. Elsner Library and High Technology Complex--A Place for Learning.

    ERIC Educational Resources Information Center

    Moore, Chas. T., Jr.; Sugiyama, Kaoru K.

    2001-01-01

    Discusses the new Paul A. Elsner Library and High Technology Complex at Mesa Community College in Mesa, Arizona. Describes six planning goals for the facility, including access, integration of services, academic linkages, college services, district-wide services, and linkages with the community. Reports that the library offers faculty support…

  3. American Indian Capacity Building in St. Paul, Minnesota.

    ERIC Educational Resources Information Center

    Eubanks, Don

    A 1996 research project in St. Paul, Minnesota, found high rates of poverty and unemployment in its American Indian population and a lack of connection between social service agencies and the Indian community. A follow-up project aimed to support the Indian community in identifying its own priorities for research and action. Eight focus groups…

  4. Colloquy to Paul Musset

    ScienceCinema

    None

    2017-12-09

    En honneur de Paul Musset il a été décidé de faire plutôt un colloque scientifique à la place d'une cérémonie. Plusieurs personnes temoignent de leurs estime et amitié pour ce physicien et ses activités

  5. 78 FR 11630 - New England Fishery Management Council; Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ..., Newburyport, MA 01950. FOR FURTHER INFORMATION CONTACT: Paul J. Howard, Executive Director, New England... multispecies fishery. A Notice of Intent to prepare an environmental impact statement (EIS) for this amendment... to Paul J. Howard (see ADDRESSES) at least 5 days prior to the meeting date. Authority: 16 U.S.C...

  6. Paul Pinsky, PhD | Division of Cancer Prevention

    Cancer.gov

    Dr. Paul Pinsky is the chief of the Early Detection Research Branch. He has a background in statistics, epidemiology and mathematical modeling. He has worked extensively with data from the Branch's two large screening trials, the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial and the National Lung Screening Trial (NLST). |

  7. 75 FR 75542 - Qualification of Drivers; Exemption Renewals; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-03

    ... of the 21 renewal applications, FMCSA renews the Federal vision exemptions for Paul G. Albrecht..., Michael J. Paul, Russell A. Payne, Rodney M. Pegg, Raymond E. Peterson, Zbigniew P. Pietranik, John C. Rodriguez, Terrance L. Trautman, Charles E. Wood, and Joseph F. Wood. In accordance with 49 U.S.C. 31136(e...

  8. Operation of SCINDA Receiver at the University of Calcutta and Space Weather Studies

    DTIC Science & Technology

    2015-02-18

    Terr . Phys., 2014]. (ii) The pole ward gradient of the Equatorial Ionization Anomaly (EIA) introduces more intense propagation effects on...in the Indian longitude sector: Case studies, T. Das, K.S. Paul and A. Paul, J. Atmos. Sol. Terr . Phys., http://dx.doi.org/10.1016/j.jastp

  9. Homelessness and Work Experience: Two Years in Saint Paul. Final Report.

    ERIC Educational Resources Information Center

    Davis, Dennis R.

    A study explored the role of work experience in addressing problems of homeless people in Saint Paul (Minnesota) during the 1989-91 grant cycles of the McKinney Job Training for the Homeless Demonstration Program. The program included a number of elements: outreach, intake, assessment and enrollment, orientation, work experience, basic…

  10. 77 FR 75589 - Prevailing Rate Systems; Redefinition of the Minneapolis-St. Paul, MN, and Southwestern Wisconsin...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-21

    ... 3206-AM75 Prevailing Rate Systems; Redefinition of the Minneapolis-St. Paul, MN, and Southwestern Wisconsin Appropriated Fund Federal Wage System Wage Areas AGENCY: U.S. Office of Personnel Management..., and Southwestern Wisconsin appropriated fund Federal Wage System wage areas. The proposed rule would...

  11. 75 FR 38076 - Carbazole Violet Pigment 23 from India: Final Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... brief. We did not receive a request for a hearing. \\1\\ Nation Ford Chemical Company and Sun Chemical... Acting Deputy Assistant Secretary Paul Piquado dated concurrently with this notice, which is hereby..., 2010. Paul Piquado, Acting Deputy Assistant Secretary for Import Administration. Appendix 1...

  12. 75 FR 23804 - Notice of Inventory Completion: Paul H. Karshner Memorial Museum, Puyallup, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-04

    ... made by the Paul H. Karshner Memorial Museum professional staff in consultation with representatives of... Memorial Museum, Puyallup, WA AGENCY: National Park Service, Interior. ACTION: Notice. Notice is here given... Memorial Museum, Puyallup, WA. The human remains were removed from the Aleutian Islands, AK. This notice is...

  13. Paul Erdos

    ERIC Educational Resources Information Center

    Monroe, Helen; Scott, Paul

    2004-01-01

    This article presents a brief biography of Paul Erdos, who focused on problem-solving, particularly in the areas of number theory, combinatorics and graph theory. During his life he had no property, no family and no fixed address. He buttered his first piece of bread at age 21. He never cooked, nor ever drove a car. Another mathematician, Ron…

  14. 77 FR 42672 - Radio Broadcasting Services; Alberton, MT; Crystal Falls, MI; Saint Paul, AR; and Waitsburg, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [MB Docket No. 12-115; DA 12-1084] Radio Broadcasting Services; Alberton, MT; Crystal Falls, MI; Saint Paul, AR; and Waitsburg, WA AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: The Audio Division, on its own motion, deletes four...

  15. Senate Confirmation Hearing IG

    NASA Image and Video Library

    2009-10-14

    Paul K. Martin, nominee for Inspector General at NASA, right, answers questions during his confirmation hearing in front of the Senate Committee on Commerce, Science and Transportation, Thursday, Oct. 15, 2009, on Capitol Hill in Washington. At left is Dr. Elizabeth M. Robinson, nominee for Chief Financial Officer for NASA. Photo Credit: (NASA/Paul E. Alers)

  16. Paul Mills Ireland III Portrait of a Soldier

    ERIC Educational Resources Information Center

    Dolan, John P.

    2013-01-01

    This dissertation explores the life and identity of Paul Mills Ireland, III. The qualitative study was conducted using the portraiture approach and was further developed by incorporating the holistic content approach of analysis in narrative research. This fifth generation soldier was the product of a strong military lineage, most of whom were…

  17. 75 FR 17901 - New England Fishery Management Council; Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-08

    ..., Newburyport, MA 01950. FOR FURTHER INFORMATION CONTACT: Paul J. Howard, Executive Director, New England... plan. There will be a presentation by scientists from the Universities of CT and RI titled ``Goals and... other auxiliary aids should be directed to Paul J. Howard (see ADDRESSES) at least 5 days prior to the...

  18. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-59) - Chehalis Covington/ Raver Paul / Paul Alston

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tippetts, Greg

    2002-04-19

    Vegetation Management along the Chehalis Covington/ Raver Paul / Paul Alston 230 and 500 kV Transmission line Corridor ROW 48/2 to 70/6 and 1/1 to 13/4. The proposed work will be accomplished in the indicated sections of the transmission line corridor with a corridor width of 250 to 442 feet. BPA proposes to clear unwanted vegetation in the rights-of-ways and around tower structures that may impede the operation and maintenance of the subject transmission lines and access roads, including Reclaim and Danger Trees. BPA plans to conduct vegetation control with the goal of removing tall growing vegetation that is currentlymore » or will soon be a hazard to the transmission line. BPA’s overall goal is to have low-growing plant communities along the rights-of-way to control the development of potentially threatening vegetation. All work will be executed in accordance with the National Electrical Safety Code and BPA standards. Danger and “C” trees and chemical treatment contract work is scheduled to begin April 29, 2002.« less

  19. Timing and causes of mid-Holocene mammoth extinction on St. Paul Island, Alaska

    PubMed Central

    Graham, Russell W.; Belmecheri, Soumaya; Choy, Kyungcheol; Culleton, Brendan J.; Davies, Lauren J.; Hritz, Carrie; Kapp, Joshua D.; Newsom, Lee A.; Rawcliffe, Ruth; Saulnier-Talbot, Émilie; Wang, Yue; Williams, John W.; Wooller, Matthew J.

    2016-01-01

    Relict woolly mammoth (Mammuthus primigenius) populations survived on several small Beringian islands for thousands of years after mainland populations went extinct. Here we present multiproxy paleoenvironmental records to investigate the timing, causes, and consequences of mammoth disappearance from St. Paul Island, Alaska. Five independent indicators of extinction show that mammoths survived on St. Paul until 5,600 ± 100 y ago. Vegetation composition remained stable during the extinction window, and there is no evidence of human presence on the island before 1787 CE, suggesting that these factors were not extinction drivers. Instead, the extinction coincided with declining freshwater resources and drier climates between 7,850 and 5,600 y ago, as inferred from sedimentary magnetic susceptibility, oxygen isotopes, and diatom and cladoceran assemblages in a sediment core from a freshwater lake on the island, and stable nitrogen isotopes from mammoth remains. Contrary to other extinction models for the St. Paul mammoth population, this evidence indicates that this mammoth population died out because of the synergistic effects of shrinking island area and freshwater scarcity caused by rising sea levels and regional climate change. Degradation of water quality by intensified mammoth activity around the lake likely exacerbated the situation. The St. Paul mammoth demise is now one of the best-dated prehistoric extinctions, highlighting freshwater limitation as an overlooked extinction driver and underscoring the vulnerability of small island populations to environmental change, even in the absence of human influence. PMID:27482085

  20. Dynamic Mechanical Testing Techniques for Cortical and Cancellous Bone

    NASA Astrophysics Data System (ADS)

    Cloete, Trevor

    2017-06-01

    Bone fracture typically occurs as an impact loading event (sporting accidents, vehicle collisions), the simulation of which requires in-depth understanding of dynamic bone behavior. Bone is a natural composite material with a complex multi length-scale hierarchical microstructure. At a macroscopic level, it is classified into hard/compact cortical bone and soft/spongy cancellous (trabecular) bone, though both are low-impedance materials relative to steels. Cortical bone is predominant in long bones, while in complex bone geometries (joints, flat bones) a cancellous bone core supports a thin cortical shell. Bone has primarily been studied at quasi-static strain rates (ɛ˙ < 1s-1), with some dynamic studies (300s-1 <ɛ˙ < 3000s-1), but rarely at intermediate strain rates (ISR) (1s-1 <ɛ˙ < 100s-1). The data shows bone to be viscoelastic, which suggests that more dynamic and ISR data is required. Furthermore, bone exhibits quasi-brittle failure, with interrupted quasi-static tests revealing a strong microstructure dependence. However, bone specimens are typically destroyed during dynamic tests, leading to a lack of dynamic microstructural damage investigations. In this paper, a short overview of dynamic bone testing is presented to give context to the challenges of testing low impedance, strain-rate dependent, non-linear, visco-elastic-brittle materials. Recent state-of-the-art experimental developments in dynamic bone testing are reviewed, with emphasis on pulse shaping, momentum trapping and ISR testing. These techniques allow for dynamic bone testing at small strains and near-constant strain rates with intact specimen recovery. The results are compared to those obtained with varying strain rate tests. Interrupted dynamic test results with microstructural analysis of the recovered specimens are presented and discussed. The paper concludes with a discussion of the experimental and modeling challenges that lie ahead in the field of dynamic bone behavior. The financial assistance of the National Research Foundation and the University of Cape Town towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at are those of the author alone.

  1. Experimental study on corrosion and precipitation in non-isothermal Pb-17Li system for development of liquid breeder blanket of fusion reactor

    NASA Astrophysics Data System (ADS)

    Kondo, Masatoshi; Ishii, Masaomi; Norimatsu, Takayoshi; Muroga, Takeo

    2017-07-01

    The corrosion characteristics of RAFM steel JLF-1 in a non-isothermal Pb-17Li flowing system were investigated by means of the corrosion test using a non-isothermal mixing pot. The corrosion test was performed at 739K with a temperature gradient of 14K for 500 hours. The corrosion tests at a static and a flowing conditions in an isothermal Pb-17Li system were also performed at the same temperature for the same duration with the non-isothermal test. Then, the effect of mass transfer both by the flow and the temperature gradient on the corrosion behaviors was featured by the comparison of these results. The corrosion was caused by the dissolution of Fe and Cr from the steel surface into the flowing Pb-17Li. The specimen surface revealed a fine granular microstructure after the corrosion tests. A large number of pebbleshaped protrusions were observed on the specimen surface. This microstructure was different from the original martensite microstructure of the steel, and might be formed by the influence of the reaction with Li component in the alloy. The formation of the granular microstructure was accelerated by the flow and the temperature gradient. Some pebble-shaped protrusions had gaps at their bases. The removal of these pebble-shaped granules by the flowing Pb-17Li might cause a small-scale corrosion-erosion. The results of metallurgical analysis indicated that a large-scale corrosion-erosion was also caused by their destruction of the corroded layer on the surface. The non-isothermal mixing pot equipped a cold trap by a metal mesh in the low temperature region. The metal elements of Fe and Cr were recovered as they precipitated on the surface of the metal mesh. It was found that a Fe-Cr binary intermetallic compound was formed in the precipitation procedure. The overall mass transfer coefficient for the dissolution type corrosion in the non-isothermal system was much bigger than that in the isothermal system. This model evaluation indicated that the temperature gradient accelerated the corrosion.

  2. Design of Microstructured Conducting Polymer Films for Enhanced Trace Explosives Detection

    NASA Astrophysics Data System (ADS)

    Laster, Jennifer S.

    The detection of trace amounts of explosive material is critical to national security. Ion mobility spectrometer (IMS)-based contact sampling continues to be a common method employed for the detection of explosives in high security checkpoint applications, such as airport security. In this process a surface of interest, such as a passenger's hands or luggage, is probed by a swab or particle trap to collect and transfer residue to an IMS for analysis. The collection of residue on a sampling swab has been shown to be a limiting step in this detection process. As such, there is significant need to develop new materials with increased adhesion to explosive analytes and with superior particle removal abilities. Here, the design of novel sampling swabs is presented for the enhanced collection of trace explosive residue from surfaces. First, the influence of the swab microstructure on the ability to remove particles from representative substrates is demonstrated. Free-standing microstructured polypyrrole (PPy) films of a variety of dimensions and form factors are fabricated using a templated electropolymerization process. The removal of polystyrene fluorescent particles from an aluminum substrate of varying surface roughness is examined as a function of the polymer microstructure. PPy microstructured films display enhanced particle removal abilities compared to PPy non-structured and current commercial films. This increase in particle removal is attributed to the increased particle-swab contact from the microstructured films. Next, the influence of the surface chemistry of sampling swabs on the collection of a representative explosive analyte, trinitrotoluene (TNT) is explored. The surface chemistry of PPy films is modified by electropolymerizaton of an N-substituted pyrrole monomer. The surface chemistries examined include a methyl, carboxylic acid, and amino-phenyl functionality. The vapor deposition of TNT on the surface of the functionalized PPy films is quantified through ultraviolet-visible (UV-vis) absorption and compared to commercial swabbing materials of varying chemistry and surface roughness. The PPy modified films with potential sites for hydrogen bonding display the highest deposition of TNT, while the Teflon coated commercial films display the lowest interaction with TNT. Finally, the desorption and release of TNT from sampling swabs is studied as an effect of temperature and of applied bias. For successful analyte detection within an IMS, the residue collected on a sampling swab must be released from the swab, typically through a thermal desorption process. In this work the release of TNT from sampling swabs is determined through solid-phase microextraction-gas chromatography mass spectrometry (SPME-GCMS). The results of this thesis provide important information on the design considerations for the development of novel particle sampling swabs with increased performance.

  3. 75. Photocopy of photograph (original print in the Minnesota Historical ...

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

    75. Photocopy of photograph (original print in the Minnesota Historical Society, St. Paul, Minnesota, ca. 1870s. #22006. Photographer: Illingworth.) VIEW TO SOUTHEAST, SHOWING THE UPPER LEVEE AND BLUSS (on left) TO WHICH THE HIGH BRIDGE WAS BUILT - Smith Avenue High Bridge, Smith Avenue between Cherokee Avenue & Cliff Street, Saint Paul, Ramsey County, MN

  4. 2010-2012 Minneapolis - St. Paul Travel Behavior Inventory |

    Science.gov Websites

    -St. Paul area conducted the survey. Methodology The TBI consists of a paper-based survey and a wearable global positioning system (GPS) survey. The data-collection process for these two surveys was independent, and the results are not intended to function together. Survey Records Survey records include

  5. E. Paul Torrance: His Life, Accomplishments, and Legacy. Research Monograph Series.

    ERIC Educational Resources Information Center

    Hebert, Thomas P.; Cramond, Bonnie; Neumeister, Kristie L. Speirs; Millar, Garnet; Silvian, Alice F.

    This monograph is designed to be a tribute to E. Paul Torrance, a renowned creativity researcher, university teacher, and mentor. It is presented in three sections, the first of which is a discussion of Torrance's life. It reviews his childhood in rural Georgia, his academic accomplishments, the emergence of his interest in creativity and the…

  6. 37. Photographic copy of historic construction drawing, ink on linen, ...

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

    37. Photographic copy of historic construction drawing, ink on linen, no date (est. January 1890) (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: Plan of masonry approach. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  7. 26. Photographic copy of historic construction drawing, ink on linen, ...

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

    26. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: General plan of truss spans. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  8. 31. Photographic copy of historic construction drawing, ink on linen, ...

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

    31. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge (truss spans): Plan of portal struts. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  9. 36. Photographic copy of historic construction drawing, ink on linen, ...

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

    36. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: General plan of west approach. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  10. 35. Photographic copy of historic construction drawing, ink on linen, ...

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

    35. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: General plan of east approach. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  11. 32. Photographic copy of historic construction drawing, ink on linen, ...

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

    32. Photographic copy of historic construction drawing, ink on linen, December 1889 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge (truss span): Detail of longitudinal & top struts. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  12. 25. Photographic copy of historic construction drawing, ink on linen, ...

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

    25. Photographic copy of historic construction drawing, ink on linen, November 1889/January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Plan and profile of Selby Avenue Bridge. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  13. 30. Photographic copy of historic construction drawing, ink on linen, ...

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

    30. Photographic copy of historic construction drawing, ink on linen, December 1889 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge (truss spans): section of roadway with details. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  14. 29. Photographic copy of historic construction drawing, ink on linen, ...

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

    29. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: Detail of small truss. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  15. 33. Photographic copy of historic construction drawing, ink on linen, ...

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

    33. Photographic copy of historic construction drawing, ink on linen, January 1890 (original filed in drawer 98, Bridge Division, Department of Public Works, St. Paul City Annex). Selby Avenue Bridge: Plan of shoes, bolsters, & rollers. - Selby Avenue Bridge, Spanning Short Line Railways track at Selby Avenue between Hamline & Snelling Avenues, Saint Paul, Ramsey County, MN

  16. Development and Motivation in/for Critical Thinking

    ERIC Educational Resources Information Center

    Riggs, Larry W.; Hellyer-Riggs, Sandra

    2014-01-01

    An explicit link between the issues of development and critical thinking is provided by Elder and Paul (1996). In their stage theory of critical thinking, Elder and Paul argued that the first stage beyond unreflective thinking is that of the challenged thinker. The challenged thinker is one who has become aware of the actual role of thinking in…

  17. The Economic Impact of Ten Cultural Institutions on the Economy of the Minneapolis-St. Paul SMSA.

    ERIC Educational Resources Information Center

    Cwi, David

    The impact on the economy of 10 cultural institutions in the Minneapolis-St. Paul area was determined by measuring their 1978 direct and indirect fianancial effects. The institutions are the Children's Theatre Company, Chimera Theatre, Cricket Theatre, Guthrie Theatre, Minneapolis Institute of Arts, Minnesota Dance Theatre, Minnesota Orchestra,…

  18. SPEAKING, WRITING, AND LISTENING IN THE ST. PAUL ELEMENTARY SCHOOLS.

    ERIC Educational Resources Information Center

    AMBROSE, HELEN; AND OTHERS

    DESIGNED AS A RESOURCE FOR ELEMENTARY SCHOOL TEACHERS TO USE IN HELPING CHILDREN THINK CLEARLY AND COMMUNICATE EFFECTIVELY, THE ST. PAUL CURRICULUM GUIDE IS DIVIDED INTO THREE SECTIONS--SPEAKING, LISTENING, AND WRITING. AN OVERVIEW OF EACH SECTION DESCRIBES CURRENT THINKING IN THE FIELD AND GENERAL SKILLS WHICH NEED TO BE ACQUIRED BY STUDENTS.…

  19. The Initial Shock: A Conversation with Paul Fussell.

    ERIC Educational Resources Information Center

    Hackney, Sheldon

    1996-01-01

    Presents an interview with Paul Fussell, author of "The Great War and Modern Memory." Fussell speaks about the destruction of that war and his own experiences as a combat officer in World War II. He also addresses his original field of study, 18th century literature, and some of the changes wrought by the 20th century. (MJP)

  20. Musings on Paul Peterson's "School Politics Chicago Style" and on the Utility of Decision-Making Models.

    ERIC Educational Resources Information Center

    Murphy, Jerome T.

    In "School Politics Chicago Style," Paul E. Peterson is quick to credit Graham Allison's work. There are major differences between them, however. The authors reach different conclusions about the role of rationality and bargaining because they use different definitions, because of the influence of the dominant mode of thinking at the…

Top